Science topic

Melanoma - Science topic

A malignant neoplasm derived from cells that are capable of forming melanin, which may occur in the skin of any part of the body, in the eye, or, rarely, in the mucous membranes of the genitalia, anus, oral cavity, or other sites. It occurs mostly in adults and may originate de novo or from a pigmented nevus or malignant lentigo. Melanomas frequently metastasize widely, and the regional lymph nodes, liver, lungs, and brain are likely to be involved. The incidence of malignant skin melanomas is rising rapidly in all parts of the world. (Stedman, 25th ed; from Rook et al., Textbook of Dermatology, 4th ed, p2445)
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Good morning, everyone! I'm Cristina Demelas, a PhD student at NOVA Medical School specializing in melanoma and pigmentation research. I'm reaching out to the scientific community for some assistance with my PhD project. Specifically, I'm in need of human melanoma cell lines that exhibit invasive and pigmented characteristics. Having access to these cell lines would significantly advance my research. Given that the literature on this topic can sometimes be conflicting, I'd greatly appreciate any guidance or recommendations on which cell lines possess these traits. If anyone has experience with such cell lines or can share them with me, it would be immensely helpful. Additionally, if you know of any labs that work with melanoma and might have the resources or expertise I'm looking for, I would be grateful if you could connect me with them. Thank you in advance for any support or insights you can provide. 🙏 Cristina
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Hi Cristina,
When you say invasive, it is not clear if you mean a cell line derived from an invasive melanoma, or one that shows invasion in an assay (in vitro or in an animal).
But anyway, on the whole, the more invasive the melanoma from which a cell line was derived, the less pigmented it is in culture. Most pigmented human melanoma lines are from primary tumours. However, there are a few exceptions, such as this one:
Meenhard Herlyn's lab in the Wistar Institute (Philadelphia) also keep a large library of human melanoma lines, and they can surely help you with finding what you want.
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...For research purposes to help others. If you are or know of anyone who is who would be willing to share his/her story, I would greatly appreciate the introduction! Thank you so much!!
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Yes. We have some melanoma survivors treated with immunotherapy for stage IV with 5 years of FU and remember now one patient with a remission of 10 years.
Immunotherapy and target treatments completely changed the future of metastatic melanoma.
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In order to study melanoma lung metastasis in aged hosts, we did RO injection of B16F10Luc2 melanoma cells (expressing firefly luciferase) into both young (16 weeks) and old (>2 years) mice. However, we noticed a fair amount of signals were coming from the eye area when doing IVIS on these mice meaning many of the cells injected were trapped in the eye and forming localized tumors instead of metastasizing to the lung. I wonder if this is a normal thing and if there are any ways to prevent this from happening.
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Retro-orbital inoculation of tumor cells is very likely to give rise to trapping of some of the injected tumor cells in the eyebed and hence tumor formation. It is better to introduce such cells via the tail vein. If a second population of cells needs to be injected i.v. as well (for example primary lymphocytes) these could be injected retro-orbitally (provided this is still allowed under the pertinent legislation). These should be primary cells in rder to avoid the problem raised in the question. It should be mentioned that detection of tumor cells in the lung upon i.v. injection is not a very good model for metastasis, its appearance most likely representing trapping of the tumor cells in the vasculature of the lung. It is a valid model to measure, for example, the potency of anti-tumor immunotherapy approaches.
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Dear all,
I was wondering if anybody has any tips regarding the transfection of human melanoma cell lines (source ATCC) using either the Neon or Nucleofactor electroporation systems.
Looking forward to hearing from you, I thank you in advance.
Regards,
Andrea
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some general tips and considerations for transfection of human melanoma cell lines using electroporation systems such as Neon or Nucleofector -- here are some key points to consider:
  1. Cell line characteristics: Different melanoma cell lines may have different transfection efficiencies and sensitivities to electroporation. It's important to choose a cell line that is suitable for the study and has been authenticated and characterized, such as those available from the ATCC.
  2. Plasmid DNA quality: Ensure high-quality plasmid DNA for transfection. Purify the DNA using reliable methods to remove impurities that could interfere with transfection efficiency.
  3. Optimization of electroporation parameters: Each electroporation system has specific settings for pulse voltage, pulse length, and number of pulses. Start with the manufacturer's recommended conditions and optimize them based on the response of the specific cell line. Factors such as cell viability, transfection efficiency, and cell recovery after electroporation should be assessed during optimization experiments.
  4. Cell density and confluence: Cell density and confluence can impact transfection efficiency. Generally, cells should be in the exponential growth phase and have a high viability. Optimal cell density and confluence should be determined experimentally for each specific cell line.
  5. Transfection reagents and buffers: Select appropriate transfection reagents and buffers compatible with the electroporation system being used. Follow the manufacturer's instructions for preparing the transfection mix and the electroporation buffer.
  6. Optimization of DNA amount: Test different amounts of plasmid DNA to determine the optimal concentration for transfection. Higher DNA concentrations may lead to increased transfection efficiency, but excessive DNA can be toxic to cells. Finding the right balance is essential.
  7. Pre-electroporation treatment: Some cell lines benefit from specific pre-electroporation treatments, such as pre-culture in low serum conditions or exposure to specific agents that enhance transfection efficiency. These treatments can be explored and optimized for the specific cell line of interest.
  8. Post-electroporation recovery: Following electroporation, allow cells to recover in a suitable culture medium for an appropriate duration. Optimize the recovery time based on cell viability and functional requirements.
  9. Validation and optimization: Assess the transfection efficiency using appropriate positive controls (e.g., fluorescent reporters or known gene targets) and negative controls (e.g., mock-transfected cells or cells transfected with irrelevant plasmids). Optimize the protocol by modifying parameters and retesting until satisfactory results are achieved.
  10. Functional assays: Perform functional assays, such as gene expression analysis, protein analysis, or functional assays specific to your research question, to assess the impact of the transfection on the desired cellular processes.
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Hi all.
Do you know the STR profile of SK-MEL-103 melanoma cell line?
I guess it is not available from ATCC...
Thank you.
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To obtain comprehensive information about the STR profile of the SK-MEL-103 melanoma cell line, I would recommend referring to scientific literature, research articles, or publicly available databases that specialize in cell line authentication. These resources may provide detailed genetic profiles, including STR profiles, for a variety of cell lines.
Reputable sources to explore for cell line authentication information include:
  1. American Type Culture Collection (ATCC): The ATCC provides authenticated cell lines and offers authentication services. They may have information about the STR profile of the SK-MEL-103 melanoma cell line.
  2. If you can not find it in ATCC, you may look for it from International Cell Line Authentication Committee (ICLAC): ICLAC is an organization that aims to promote cell line authentication and provide guidelines and resources for researchers. They might have information on commonly used cell lines, including SK-MEL-103 melanoma.
  3. Published research articles: Scientific literature often includes information about the genetic characterization and authentication of specific cell lines. Searching for articles specifically focused on SK-MEL-103 melanoma may yield relevant information regarding its STR profile.
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Dear Researchers,
I've been working with a PhD student on leader and follower cells research on spheroid culture.
We want to isolate leader cells from cancer cell spheroids. Our best bet from other researcher studies is to use FACs but our faculty does not have the machine
Do you have any idea how to isolate leader cell from the rest of spheroid? Any ideas are really appreciated
Cheers
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I think this lab is doing exactly what you are looking for.
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I am looking for a well-characterized melanoma cell line that is less aggressive than SK-MEL-28, and I can culture in spheroids. Ideally, commercially available at ATCC.
Thank you so much!
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Thank you so much for your fast answer. All these cell lines have a fibroblast or fibroblast-like morphology. I would like to find one that's melanocyte morphology and is less aggressive than SK-MEL-28.
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Most protocols do not include details about preparing cell lines for tumor inoculation and various labs seem to do things differently based on my personal experience. Could anyone please share what they personally do for the following things:
1. Do you keep the cancer cells warm or on ice prior to inoculation? Why?
2. What gage needle do you use (for subcutaneous)? Why?
3. Do you load the needle any special way to avoid shearing?
Thank you for sharing! Any other general related comments are also welcome. We are specifically working with various melanoma cell lines.
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1. Do you keep the cancer cells warm or on ice prior to inoculation? Why?
You should keep cancer cells on ice to maintain the viability of the cells temporarily. You should inject cells as quickly as possible after preparation because viability slowly decreases over time, even on ice.
2. What gage needle do you use (for subcutaneous)? Why?
You should use a 25g 5/8” needle for subcutaneous application.
For i.p. injections of adult mice, you may use 26 g 1/2” needle, for i.v. injections, you may use 26-27g 1/2” needle and a 30g 1/2” needle for some orthotopic injections.
You need to know that the higher the gauze number, the smaller the diameter of the needle. This will then exert more stress on the material and any cells in it. High shear stress and pressure can decrease cell viability.
The lower the gauze number, the stronger the needle, resulting in less chance of bending or breaking.
3. Do you load the needle any special way to avoid shearing?
Hold a mouse with one hand, use the other hand to slide needle 5 to 10 mm subcutaneously and inject 50-100 µl cell suspension (Tumor cells - 1x10^5 - 1x10^6 cells). You should watch for appearance of a bleb. Failure to insert needle far enough will result in leakage of tumor suspension when mice massage the area after injection.
Some comments that could be helpful:
1. Do not let the syringe with cell suspension sit undisturbed on bench for more than 5 minutes because the cells can settle quickly.
2. Be sure to resuspend cells well in the syringe barrel before each injection.
3. Do not pass the cells through needle more than once since this will shear cells and reduce total cell number.
Also, please refer to the article attached below for more information.
(See basic protocol 1)
Best.
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I am working on B16F10 melanoma cells. Yesterday I thawed the cells that I had freezed last week and saw some floating black spots. Is it a sign of contamination? If so, what type of contamination is it? This cell line produces melatonin black pigment too so I am not sure if it is normal to have black debris. This is passage 3 and I bought this cell line from ATCC.
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The media looks normal with pinkish color Not cloudy at all. I use 10% DMEM and add 1% pen/strep for the culture media.
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Goodnight
Sorry to bother in this Sunday
But I would like to ask a few questions:
Does anyone know about how to induce the generation of polyploid giant cancer cells (PGCCs) in melanomas with "targeted drugs"?
How to measure the presence of polyploidy in the tumor?
How to induce the generation of giant polyploid cancer cells (PGCCs) in melanomas?
Is there any protocol to induce the generation of polyploid giant cancer cells (PGCCs) in melanomas?
Is there any way to study the immortalization and regeneration of tumors with cellular and molecular biology? Is there any protocol?
Best regards,
Matheus Correia Casotti
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Scientists have developed a new method that can easily create immortal human mammary epithelial cells. The cells could greatly facilitate the examination of cell immortalization as it actually occurs during cancer progression. Every day, some of your cells stop dividing, and that's a good thing.
I am sharing a pdf, it would be very helpful for you.
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Hello everyone.
We isolated CD8+PD1+ T cells from the peripheral blood of a metastatic melanoma patient, with 99.5% isolation purity and 98% PD1 expression. We activated cells with Human TransACT "Miltenyi Biotec". After the activation phase had been finished, we left the cells in the expansion phase for 14 days, and then we performed a flow cytometry experiment to identify the phenotypic features of the expanded population. We found out that PD1 expression decreased from 97% to nearly 50%, but we still have CD8+PD1+ purity of 96%.
The part we didn't understand, what was the cause that led CD8+PD1+ T cells to decrease PD1 expression?
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PD-1 expression on naïve T cells is induced upon TCR activation. This transient expression decreases in absence of TCR signaling but is maintained upon chronic activation with a persisting epitope target. You used Human TransACT "Miltenyi Biotec", it may create a chronic activation on CD8+ Tcells. May be this activation results in lower expression of PD-1. Good luck
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Dear fellow researchers,
my histo team and I came across some trouble in reducing background autofluorescent noise in FFPE tissue from primary melanoma. So far, we have been able to quench distinct portions of noise in 488 and 546 with Sudan-B. Still, we suffer from problems in the 647 channel and in 750/790 regarding some antibodies.
Can you suggest other reliably techniques, especially for primary melanoma tissue?
Best wishes and take care,
Mathias
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If you know the source of the autofluorescence and it does not overlap with your targeted flourophore then you could use sequential scanning and tune the detector of the confocal to isolate your target and the autofluorescence in order to separate them. Confocal microscopy is always the better bet in cases of autofluorescence over standard bandpass filters of a fluorescent scope.
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If any of you have worked with the MM28 cell line (uveal melanoma metastasis) how did you freeze it to maintain the best cell viability?
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I have not worked with MM28 cell line. But generally, while freezing cells the main points to remember in order to get high cell viability on thawing are:
1. Freeze cells when they are 80% confluent.
2. Carry out gradual freezing of cells i.e., -1 degree C/minute before you place your cells in liquid nitrogen. You may use Mr. Frosty freezing container commercially available that will help in gradual cooling. Place the freezing vials in Mr. Frosty container in -70°C freezer for a minimum of 4 hours and then remove frozen tubes and place them in liquid nitrogen (vapor phase) for long-term storage. Always use pre-cooled freezing vials. Freeze approx. 2 million cells per ml per vial.
3. MM28 cells are frozen in 90% FBS and 10% DMSO as the freezing medium.
Best.
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Hi,
I have ordered A375 melanoma cell lines and the ATCC website recommended using DMEM+10% FBS. I was wondering if the cells can be grown in RPMI 1640+10% FBS as I am using it for some other cell lines.
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RPMI 1640, based on the 5A Medium (developed by McCoy et al. 1959) and modified for the long-term culture of peripheral blood lymphocytes, is characterized by low levels of calcium and magnesium and high levels of phosphate. Multiple media were developed on the path to this medium (e.g., RPMI 1629, 1630, and 1634). It is widely used as a medium for suspension cultures; for example, of white blood cells, lymphocytes, and hybridomas. Please refer to the article below for more details.
I would recommend the use of DMEM+10% FBS for A375 melanoma cell line as mentioned in the ATCC website.
Best.
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Dear colleagues, we need to induce a melanoma-derived tumor in the monkeys. Whereas, murine melanoma cell lines are available, i can't find any similar monkey cell line. Is it possible and reasonable to induce tumors in monkeys by using human cell lines?
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As to the first part of your question: the answer is no: there are currently about 1200 non-human primates cell lines in the Cellosaurus and none of them is from a melanoma. This is not surprising as this is a very rare disease in monkey. See for example:
Where it is stated that searches in a number of bibliographical databases "did not reveal any published report of uveal melanoma in a nonhuman primate."
and
Where it is said that "To our knowledge, this is the first documented case of melanoma in a cynomolgus monkey."
So its unlikley someone has had the opportunity to establish a non-human primate melanoma cell lines.
Best
Amos
PS: Disregard the 1st answer: there are a number of companies distributing cell lines that have people answering any question on cell lines by pointing to their catalog even if it is not relevant. AcceGen is not distributing any monkey melanoma cell line
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Can anyone please share Skin cancer(melanoma) dataset please.
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I am using the B16-F10 cell line as a model for melanoma in mice. after treatment, i see an increase in the ratio of M1/M2 macrophages in tumor tissue. i suspect that the treatment I use either reprograms M2 TAMs to M1 or increases M1 migration into tumors from other sites? I was thinking of using a drug (after the tumor reaches 100mm3 in size) to inhibit the recruitment of any new microphage into the tumor thus I can distinguish whether TAMs already in the tumor are reprogrammed to M1 or M1 are migrating from other sites to the tumor.
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By decreasing extracellular acidity (e.g. bicarbonate) and decreasing intracellular alkalinity (e.g. amiloride) you will substantially decrease migration.
Another useful drug is dasatinib that inhibits Src phosphorylation and limits the cytoskeleton activity involved in migration.
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I recently received these cells as a gift from one of my colleagues. I wish to use these in my research which is on anticancer activity of some cyanobacteria species. I couldn't find any broad information about these cells on internet or from literature. I am wondering if these cells are suitable for this kind of studies?
Thank you.
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Dear Malcom,
Thank you very much for your informative answer. I did same as you mentioned with normal HDF along with a panel of cancer cells.
Thank you again.
Regards
Menuja
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I am working on a deep learning-based analysis to detect Melanoma Cancer. I want to use all types of algorithms to get the best possible solution.
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I hope this email finds you well.
I would like to invite you to have a look on the following links.
Thank you very much for your time and efforts.
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I need a melanoma dataset where the lines are classified. that is, the images are marked that they have lines and what category these lines belong to.
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The following PLCO Melanoma dataset(s) are available for delivery on CDAS. For each dataset, a Data Dictionary that describes the data is publicly available.
Kind Regards
Qamar Ul Islam
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Hello everybody,
I’m interested in calibrating 2‐Deoxy‐D‐glucose in different concentrations in melanoma cell line. How do you recommend me examining the effect of 2‐Deoxy‐D‐glucose on the cells other than measuring the lactate levels? Do you recommend any genes that are affected in their expression levels to measure using real time PCR for example?
Thanks ahead,
Hanna.
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Besides lactate levels, you can try measuring other proteins. Please refer to the research article below for more information.
Highlight:
Nutrient deprivation has been shown to cause cancer cell death. To exploit nutrient deprivation as anti-cancer therapy, we investigated the effects of the anti-metabolite 2-deoxy-D-glucose on breast cancer cells in vitro. This compound has been shown to inhibit glucose metabolism. Treatment of human breast cancer cell lines with 2-deoxy-D-glucose results in cessation of cell growth in a dose dependent manner. Cell viability as measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide conversion assay and clonogenic survival are decreased with 2-deoxy-D-glucose treatment indicating that 2-deoxy-D-glucose causes breast cancer cell death. The cell death induced by 2-deoxy-D-glucose was found to be due to apoptosis as demonstrated by induction of caspase 3 activity and cleavage of poly (ADP-ribose) polymerase. Breast cancer cells treated with 2-deoxy-D-glucose express higher levels of Glut1 transporter protein as measured by Western blot analysis and have increased glucose uptake compared to non-treated breast cancer cells. From these results we conclude that 2-deoxy-D-glucose treatment causes death in human breast cancer cell lines by the activation of the apoptotic pathway. Our data suggest that breast cancer cells treated with 2-deoxy-D-glucose accelerate their own demise by initially expressing high levels of glucose transporter protein, which allows increased uptake of 2-deoxy-D-glucose, and subsequent induction of cell death. These data support the targeting of glucose metabolism as a site for chemotherapeutic intervention by agents such as 2-deoxy-D-glucose.
I hope this helps.
Best.
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I have noticed morphological changes in primary melanoma cell cultures after switching to a different brand of FBS, the cells are circled in blue. Some cells began to form a more round shape with black particles attached to and surrounding the cells.
After the removal of antibiotics, the black particles seemed to increase as free floating particles with no particular motion. I assumed that it was mycoplasma contamination and tested them accordingly via pcr. The results were negative. I then assumed that it was potentially apoptotic bodies from low quality FBS so I decontaminated everything and purchased new FBS. After activating a stock, the cells seemed to be much healthier but after a few passages, have begun to exhibit the same changes again.
The cell passage number is <10 and I have passaged this cell line above 10 before and didn't see these changes so I assume its not straying further into abnormality. Once they are above 50% confluency, they morphological changes are gone and they assume their shape. Is this a potential other form of contamination or something that is exhibited by some primary cancer cell lines?
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Interested
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I am currently started working on the analysis of Melanoma Cancer by using DL Algorithms. I got to know that Metastasis is the spread of cancer from one organ to another. On the other hand, the physiological process through which new blood vessels develop from pre-existing vessels formed during the vasculogenesis process is known as angiogenesis. I need a proper explanation and relation between angiogenesis and metastasis.
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When cancer is initiated and starts growing, the tumor tissue requires nutrients and oxygen because they are rapidly dividing. It is this requirement of the tumor that causes stimulation of angiogenesis. The angiogenic stimulators like VEGF are released by the tumor cells which in its presence endothelial cells will proliferate and migrate, eventually forming tube structures resembling capillaries. VEGF causes a signaling cascade in endothelial cells. Thus, formation of new blood vessels will satisfy the nutritional and oxygen requirements of the growing tumor. The growing tumor can invade the surrounding tissue with the help of matrix metalloproteinases that participate in the degradation of ECM components, including the basement membrane and the tumor surface, resulting in tumor cell migration into the nearby tissue. Thereafter the cancer cells undergo intravasation into the surrounding vasculature or lymphatic system and survive in circulation, and then undergo extravasation from vasculature to secondary tissue to form secondary tumor, a process known as metastasis.
Thus, the relationship between angiogenesis and metastasis is that the tumor micro vessel density is directly related to increased metastatic potential and therefore leading to poor survival in all forms of cancer.
I hope this is helpful.
Best.
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The sun’s UV rays help your body make this nutrient, which is important for your bones, blood cells, and immune system. It also helps you take in and use certain minerals, like calcium and phosphorus. And while most people get enough vitamin D from food, children who don’t can get rickets, which softens and weakens their bones.
Moderate amounts of sun over your lifetime, especially in your teen and young adult years, might make you less likely to have problems seeing things at a distance (nearsightedness). But too much direct sunlight can hurt your eyes. It can lead to blurred vision and raise your chances of cataracts.   
This also raises your chances of skin cancer. If you do it before age 35, you’re 60% more likely to get melanoma, the most serious form. Even one session can raise your odds of melanoma by 20% and other types by as much as 65%. If you want that all-over body tan, tanning lotions might be an option. Most are safe, but they usually don’t have sunscreen in them, so don’t forget to put that on as well.
 
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My mother (who lived over 100 years) religiously stayed in the sun every day for 20 minutes, but not when the sun is very hot (in the afternoon), preferably in the morning. She used to say that a bit of the sun made her feel better as compared to cloudy days with no sun. She decided the 20 minute interval from experience.
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Figure 3.1. TBX3and CERS1 are inversely correlated in melanoma: (A) The Cancer Genome Atlas (TCGA) melanoma samples (black line) were scored and ranked according to the Verfaillie invasive gene signature (Verfaillie et al., 2015). Vertical grey lines indicate expression of the indicated gene in each melanoma sample. The purple line indicates the moving average of (left panel) TBX3 or (right panel) CERS1 mRNA expression across 20 melanomas. Bioinformatic analysis using TCGA SKM. A correlation between TBX3 mRNA and melanoma invasiveness was performed in melanoma patient samples n=303.
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X axis are gene expression values. Left y axis are correlation coefficient, right y axis is metastasis score
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Hello everybody!
We are trying to isolate DNA/RNA from thin primary FFPE melanomas. We use a protocol based on silica columns for the isolation of DNA/RNA from the same specimens.
Although the DNA that we get seems to work fine on subsequent enzymatic reactions (PCR, sequencing), we encounter inhibitory problems with the RNA samples. In particular, it seems that RNAs are contaminated with melanin. The amount of RNA that we have is very limited, 30 μl with a concentration of 20-50 ng/μl.
Has anybody used the CTAB-urea method or a column based method for removal of melanin from RNA preparations? Our problem is the very limited amount of the starting RNA.
Thanks a lot,
Olga
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Your problem is with the ffpe method. Make sure the steps are repeated with precision materials. However, you can use other methods such as trisol to extract RNA and phenol / chloroform to extract DNA. The ctab method is used to extract the plant genome due to the high amount of carbohydrates and to extract the genomes of some bacteria for the molecular work of typing. In my opinion, repeat the paraffin removal steps again and use more Poly A due to the low amount of tissue and genome in the paraffin tissue used.
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I am growing a Melanoma cell line expressing Ovalbumin (OVA) protein. I am looking for maintaining the stable expression of the protein by cell line and the researcher use G418 with a variable concentration in different papers. Can anyone have experience with starting the selection process? what is optimum concentration and how to select it? ED50?
Thanking you in advance.
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It depends on the promoter strength of neoR gene and the copy number of the overexpression construct with a cell. The gold standard is 0.4mg/ml.
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I met a problem when I was doing frozen section for mice melanoma tissue. Based on the confocal results I got as attached, seems like the cell structures are destroyed (looks like a network) and all cells are CD8 positive (T cell markers) and F4/80 positive (macrophage markers). Is there any potential reason for this? I used 10% formalin to fix the tissue overnight. Is there anything wrong with this fixation procedure?
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For frozen section usually 4% PFA is a good fixative for overnight fixing followed by serial sucrose treatments. Sucrose treatment suppose to cryopreserve the cells/ prevent from damaging your cells from negative 80. If you do formalin fixing, then you usually have to do antigen retrieval (heat retrieval for example) in order to expose the antigens. Also, have you dried out your tissue during the IHC procedure? If you dry out your sections during IHC, tissue could look like this! try avoiding drying out your sections except the initial tissue adhesion into slide glass before washing off OCT from the tissue.
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Hello,
are there any murine cancer cell lines out there that once injected subcu will metastasize to the liver? I know there is LLC and some melanoma cell lines that will go to the lung. Appreciate any input!
thanks
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Dear Christof!
Please You read this article
Comparison of Different Colorectal Cancer With Liver Metastases Models Using Six Colorectal Cancer Cell Lines (attached)
Cell Culture Six generally available human CRC cell lines, SW620, SW480, HCT116, HT29, LOVO and DLD1,
Fig. 1 Bioluminescence monitors tumor burden growth and liver metastases in the orthotopic transplantation group
Fig. 2 Liver metastases in the ectopic transplantation group. a The number of animals proceed to develop into liver metastases via six CRC cell lines. b
Mouse peritoneal metastasis models. MKN1-Luc, N87, KATO III, MKN45-Luc, NUGC4, and OCUM-1
Mouse hepatic metastasis models. Under general anesthesia, we mobilized and excised the spleens of nude mouse, which were then subcutaneously implanted. A total of 0.5×106 MKN45-Luc cells were suspended in 100 μl of PBS and injected into the subcutaneously implanted spleens. For direct injection into the portal vein, nude mice and NOD/SCID mice were placed under general anesthesia and laparotomized. Then, 1.0×106 MKN45-Luc and 0.5×106 MKN1-Luc cells were suspended in 100 μl of PBS and directly injected into the portal veins of mice using a 35-gauge NanoNeedle (NIPPON Genetics, Tokyo, Japan). After injection of the cell suspensions, we oppressed the puncture site of the portal vein using SURGICEL (Johnson & Johnson, NJ, USA) for a few minutes. Twelve weeks after injection, these mice were killed and hepatic metastasis formation was observed under direct viewing.
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actually I searched the related web sites, but the quantity of samples are maximum 20 or 30 pictures, but I saw in articles that there are datasets from theses 2 sources with enough number of samples (more than 100).!!!
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The International Skin Imaging Collaboration: Melanoma Project is an academia and industry partnership designed to facilitate the application of digital skin imaging to help reduce melanoma mortality. When recognized and treated in its earliest stages, melanoma is readily curable. Digital images of skin lesions can be used to educate professionals and the public in melanoma recognition as well as directly aid in the diagnosis of melanoma through teledermatology, clinical decision support, and automated diagnosis. Currently, a lack of standards for dermatologic imaging undermines the quality and usefulness of skin lesion imaging. ISIC is developing proposed standards to address the technologies, techniques, and terminology used in skin imaging with special attention to the issues of privacy and interoperability (i.e., the ability to share images across technology and clinical platforms). In addition, ISIC has developed and is expanding an open source public access archive of skin images to test and validate the proposed standards. This archive serves as a public resource of images for teaching and for the development and testing of automated diagnostic systems.
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Hello people of ResearchGate,
I need your help in identifying a contamination that has appeared in our cell cultures. We have discovered these contaminations in various cell cultures cultured in the same cell lab. When observed through a microscope, the contaminants appear as spherical objects, visible even with a 20x objective. The medium does not change colour, and when measured I have seen that the contaminants are all approximately of the same size with a diameter of ~9 mikrometer. My guess is that it might be some sort of fungi, maybe yeast, since they are so big and we use cell culture medium with antibiotics.
I have attached a picture taken with our microscope (20x objective) of the culture. It is supposed to be an adherent melanoma cell line (the big, darker stuff), and the contaminants are the bright, spherical objects floating above the melanoma cells. Does anyone of you have any idea about what it might be?
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Did you try to grow this contaminant on mycological media, such as Sabouraud dextrose agar, or Pal sunflower seed medium? If you find any colony suspected as fungus, try to prepare wet mount preparation in Narayan stain to study the morphology. We have developed Pal sunflower seed medium in 1980 and Narayan stain in 1998 for the study of fungi. Once you are sure that contaminant is a fungus, you should try to fumigate your tissue culture laboratory and also add broad spectrum antifungal antibiotics to the cell culture medium. Such problem may occur when we work with tissue culture.
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Hi all,
I am looking for a dataset of melanoma patient attributes. So for example age, sex, history of melanoma, history of cancer, family history, benign or malignant.
I hope my question was clear. Any help would be greatly appreciated.
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Hi Jonathan,
Here you have some publicly available datasets (free registration/acces request needed):
- US National Cancer Institute: https://cdas.cancer.gov/datasets/plco/11/
- US Center fo Disease Control and Prevention https://www.cdc.gov/cancer/uscs/public-use/obtain-data.htm
I hope this helps,
Regards
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I was asked to do a presentation on the following paper:
Juratli, Mazen & Menyaev, Yulian & Sarimollaoglu, Mustafa & Siegel, Eric & Nedosekin, Dmitry & Suen, James & Melerzanov, Alexander & Juratli, Tareq & Galanzha, Ekaterina & Zharov, Vladimir. (2016). Real-Time Label-Free Embolus Detection Using In Vivo Photoacoustic Flow Cytometry. PloS one. 11. e0156269. 10.1371/journal.pone.0156269.
In the introduction, it says something like this: "However, application of the PA technique to the real-time monitoring of embolus dynamics during a medical intervention in large vessels is challenging. The main goal in this paper is to demonstrate that the in vivo PAFC can rapidly detect emboli triggered by melanoma and (...)"
- My interpretation of this is that, for some reason, PA isn't enough so it must be used together with flow cytometry. I would like to know why and what is the difference.
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Dear Mariana Nunes,
Photoacoustics (PA) means the study of vibrations induced in matter by light. Laser light causes localized heating when it is absorbed by a surface. This in turn makes the target area expand and sends a pressure wave through the rest of the material. This effect enables imaging of opaque systems, particularly biological samples. Photoacoustics flow‐cytometry technique (PAFC) is based on non-radiative transformation of the absorbed laser energy into acoustic waves caused by the fast thermal expansion of the heated sample. This phenomenon is monitored through the changes in optical characteristics that are detected by an ultrasound transducer attached to the sample. For in vivo applications, PAFC either uses label‐free detection of cells with intrinsically light‐absorbing chromophores (e.g., hemoglobin, melanin, or cytochromes) or cell labeling with strongly absorbing dyes or nanoparticles as PA molecular probes. In general, PAFC is considered acoustic analysis, meaning the data collected and analyzed would be on sound waves. Although, PAFC is conducted using the same process as conventional flow cytometry, the sensor used is a transducer rather than light capturing sensors. Where photosensors convert light energy to electrical energy, transducers convert sound waves to electrical energy.
Hope this helps.
Best - Pradyumna
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Could any scientific researcher guide me to obtain SW480 or Human melanoma cell lines in Egypt. Thanks in advance
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Hi Heba,
I agree with Brian the human colon cancer cells (SW480) are obtained from ATCC (American Type Culture Collection, United States) or from Europe. So you should contact them via mail to provide you the instructions.
Here's the link of the company:
Hope this may help you
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I need a dermoscopic image database to test an algorithm for automatic diagnose. In particular I am interested in images with blue-black colors within the lesion.
Can anyone tell me where to find it?
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I have 92-1 of melanoma cell line , when i thawed them they were totally normal , but after first passage , the cells begun not growing well and not totally attaching on the bottom of the flask .
looking for your reply
Thank you very much
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I think Silvia Torchio means this could be the reason of the culture problem.
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I am currently doing some CRISPR/Cas9 KO on human melanoma cell lines. I found in different articles the puromycin concentration for selection in A375 (1 μg/ml). But, I cannot find this information for the WM3211 melanoma cell line.
Has anyone ever use this WM3211 cell line for gene KO experiment?
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For selection 1 microgram/ml should work with your cell line in 3-4 days. After selection, change concentration to 0.5 microgram/ml. Note that cell killing works best when cell density is low (~50%).
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In addition to clinical examination, dermoscopy and RCM help in diagnosing AHM. Which would be a better option between the two? Why?
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Thanks Khadija Elboukhari for your excellent insight.
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We are working in our lab about melanoma. In each in vivo experiment, we digest tumors to have a single cell suspension. The problem is that the precntage of viable cells is very low, between 10 and 20%. We are looking for another protocol through which we can get a higher percentage of viable cells.
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By using the following cell isolation protocol, even if specified for glioblastoma cells in the protocol, we obained a high yield in viable tumor cells from tumors of various entities (Patient derived, PDX and mouse tumors). We've never tried melanoma, though.
Otherwise, you might try the dissociation procedure published in the following article, just skipping the subsequent steps for the MACS sorting:
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A prospective study has been published by Wen-Qing Li (JAMA Intern Med. doi:10.1001/jamainternmed.2014.594, online April 7, 2014) raising an intriguing question, stating that Sildenafil use for ED showed a statistically significant elevated risk of melanoma. We´re really concerned about this. Any insight regarding this important subject?
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Use of viagra does not cause the development of melanoma.
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Hi all - I apologize if this has been covered before.
What can I expect from a tumor grown from B16-F10 cells in a C57B6/J mouse?
30 days after subcutaneous injection of 10^6 cells, I harvested a massive growth from the abdomen that I assume was a metastasis. However it was WAY bigger than the subcutaneous growth. It is also very soft/mushy.
Is that normal? Do these cells result in very soft tumors usually? The subcutaneous portion was much firmer.
Could it be that they grew too fast and the whole thing became necrotic? Unfortunately the mouse died the morning of the planned sacrifice, so I was unable to properly perfuse and harvest the way I wanted to.
Thank you!
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Hii,
I have a Question regarding this.
Can you suggest me the protocol of tumor injection i.e any Research paper reference.?
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I am doing research on melanoma detection for dark skin people. so it's very difficult to identify the dark skin images, please tell me the idea to get the dark skins.
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Dear Ahmed do follow this link to a project i was involved in last year. There is a dermoscopy tool kit with links to lots of website, where you will find an abidance of images for every skin type and skin lesion:
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My current job is make spheroids from melanoma cell lines. But i dont know how to identify spheroids. How can i know that i have a spheroid and not a cell cluster?
Please help me, this is my essay for the thesis
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Ana Santos You say these are cell lines so, perhaps there is a publication (even if very old) that characterized these lines and by reading their discussion you can get some additional info about how these lines form spheroids. In general, cells form spheroids in conditions of low adhesion to the plate, so you can try different plates (flat vs round bottom low adhesion) and observe the cell clusters. The best way I know of identifying spheroids is to watch the cells make them. So I would suggest to watch the cells closely for a few days.
Hope this helps
Victoria
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Hi,
im trying to make spheroids from melanoma cell culture, most specific with cells A375, G361 and SK-MEL-1. If someone try please let me know how do you meke, because im new in this area. Thanks
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Hi Ana,
I also tried to make spheroids from these cell lines, however for A375 and G361 the spheroids were not as tight and partially disintegrated when handling. I used liquid overlay method and cultered the cells in ultra-low attachment plates (96 well format with round bottom).
Here are some protocols that worked out well for me:
For SK-Mel-1 cells I didn't try, but to my knowledge they are a suspesion cell line, so growing as spheroids might not be feasable for this cell line.
Hope this helps :)
All the best, Verena
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Hi there I experienced problems with autofluorescence of RBC on FFPE sections of human melanoma. Used AF555 sek. Ab to detect. Was thinking about using the trueview form Vector labs but they suggest a certain mounting medium. I have to use ProLong Glas antifade mounting medium from ThermoFischer which has a higher refractive index since I'm working with an LSM microscope. Does anyone has experience already with Trueview in combination with mounting media others than suggested by Vector labs? Cheers, David
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Michael Lee No, we have not tried Prolong Glass yet.
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I am working on melanoma B16-F10 cell line and after treatment whit different concentration of drug I do SRB protocol then I read their absorb at wavelengths of 545 nm. now, how to analyze these results? What should be the range of control absorbency?
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Hi
You can use the following protocol to calculate IC 50 for your drug. PDF attached for your reference.
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I want to inject B16 cells into C57BL/6 mice as a melanoma model to study tumor immunology. But I'm confused the injection type. Both subcutaneous and intradermal injection have been used. Which one should I choose?
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Naive question here, but how do you know if you are subcutaneous or intradermal. We've recently injected mice with the intention of injecting s.c. However, 1/3 of the tumors are growing much more slowing. I have been told this may mean that the tumors were injected intradermally. Is there any way to prevent this? Thank you.
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Hi,
Our B16F10 cell line from ATCC encountered massive cell death after switching the growth media from RPMI to DMEM.
We were stuck with RPMI( 10% FBS, 5ml P/S) for the first 2 passages with the lab mistakenly ordered DMEM w/o sodium pyruvate & l-glutamine. The B16F10 cells looked healthy as we split them at the subcultivation rate of 1:5 and passaged them every 3-4 days.
Then, the growth media was replaced with DMEM when the glutiMAX arrived. 5mL of glutamax (5mM) + 10% FBS, 5mL p/s was added to prepare the DMEM. The cells were split 4 days ago with the new DMEM and at a much lower ratio of 1:12. We checked the cells today and they were all dead. Shown in the pictures.
Any advice for the troubleshoot would be very much appreciated! Thank you in advice for the help!
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B16 variants require media with specific AAs to form melanin. Thus, in RPMI-1640 they loose the brown color. It is best to culture in the recommended media of MEM with additional NEAA and EAA. This maintains the melanin.
As mentioned B16 variants are adherent cells, but when they become acidic or nutrient deprived they form cell mats and also release cells from the plastic surface. Further, they form exosomes and appear to have a large number of floating cell fragments. Thus, a 2 to 3 time per week split is optimal. Also assure that the split results in about 20% confluence.
Hope this helps.
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I tested 25 ug/ml and 40ug/ml of Fluorescently labeled transferrin in melanome cells during different times of observation, but no fluorescent signal was detected inside the cells.
Is there anyone here who has had the same problem?
Thank you.
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I'm coming a bit late but I also have trouble with transferrin, I can't detect any signal after using the concentration given by the literature. Did you try to use it at a higher concentration on the HDF cells? Do you remember if it worked ?
I do thank you
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In patients affected by metastatic melanoma (BRAF mutated) that were previously treated with target terapy (dabrafenib 75mg x 3 / day; trametinib 2mg / day) is it recommended to be treated with combined immunotherapy (Ipilimumab + Nivolumab) or there are better alternatives?
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Michele:
Pembrolizumab (Keytruda) in Melanoma:
Ascierto PA DR, et al. KEYNOTE-002 Part 3: Phase 2 randomized study of 1L dabrafenib (D) and trametinib (T) plus pembrolizumab (Pembro) or placebo (PBO) for BRAF-mutant advanced melanoma. ESMO 2018 Congress.
Carlino MS, Long GV, Schadendorf D, et al. Outcomes by line of therapy and programmed death ligand 1 expression in patients with advanced melanoma treated with pembrolizumab or ipilimumab in KEYNOTE-006: A randomised clinical trial. Eur J Cancer. 2018 09; 101:236-243.
Daud AI, Wolchok JD, Robert C, et al. Programmed Death-Ligand 1 Expression and Response to the Anti-Programmed Death 1 Antibody Pembrolizumab in Melanoma. J Clin Oncol. 2016 12; 34(34):4102-4109.
Eggermont AMM, Blank CU, Mandala M, Long GV, Atkinson V, Dalle S, et al. Adjuvant Pembrolizumab versus Placebo in Resected Stage III Melanoma. The New England journal of medicine 2018;378:1789-801.
Hamid O, Robert C, Daud A, Hodi FS, Hwu W-J, Kefford R, et al. 5-year survival outcomes in patients (pts) with advanced melanoma treated with pembrolizumab (pembro) in KEYNOTE 001. Journal of Clinical Oncology 2018;36:9516-
Hodi FS, Hwu WJ, Kefford R, et al. Evaluation of Immune-Related Response Criteria and RECIST v1.1 in Patients With Advanced Melanoma Treated With Pembrolizumab. J Clin Oncol. 2016 05 01; 34(13):1510-7.
Kluger HM, Chiang V, Mahajan A, Zito CR, Sznol M, Tran T, et al. Long-Term Survival of Patients With Melanoma With Active Brain Metastases Treated With Pembrolizumab on a Phase II Trial. Journal of clinical oncology 2018:JCO1800204.
Long GV, Schachter J, Ribas A, Arance AM, Grob J-J, Mortier L, et al. 4-year survival and outcomes after cessation of pembrolizumab (pembro) after 2-years in patients (pts) with ipilimumab (ipi)-naive advanced melanoma in KEYNOTE-006. Journal of Clinical Oncology 2018;36:9503-
Robert C, Ribas A, Hamid O, et al. Three-year overall survival for patients with advanced melanoma treated with pembrolizumab in KEYNOTE-001. Journal of Clinical Oncology 2016 34:15_suppl, 9503-9503.
Robert C, Ribas A, Hamid O, Daud A, Wolchok JD, Joshua AM, et al. Durable Complete Response After Discontinuation of Pembrolizumab in Patients With Metastatic Melanoma. Journal of clinical oncology : official journal of the American Society of Clinical Oncology 2018;36:1668-74.
Schachter J, Ribas A, Long GV, Arance A, Grob JJ, Mortier L, et al. Pembrolizumab versus ipilimumab for advanced melanoma: final overall survival results of a multicentre, randomised, open-label phase 3 study (KEYNOTE-006). Lancet 2017;390:1853-62.
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I’ve used the same normalization and chip to search a gene expression in R2 Genomics Analysis and Visualization Plataform, but I have compared very different cells (like lung cancer and melanoma). So my doubt is: is it correct/safe to say that a gene is more expressed in lung cancer, for example, than in melanoma (p<0,05) based on comparations made in R2 Genomics?
Ps: my intention is to prove this experimentally, and the results obtainned on R2 would serve as a guide for me.
thank you!
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What is the normalization based on?
I think differences in gene expression between tissues are tricky on two levels.
In the first place, there is the normalization issue. In my experience, if you test for differential gene expression between tissues, a large proportion of the transcriptome comes out DEG, and it all depends on the normalizations used. So for a given gene: do you consider its expression relative to the rest of the transcriptome? Dangerous, because highly expressed genes in the background may "dilute" your transcript of interest, even if stoichiometrically, it is "upregulated" relative to the genes it interacts with. Or do you normalize relative to housekeeping genes? It is known that housekeeping genes exhibit tissue-specific expression. Do you consider it relative to the genes it interacts with? Interesting, but requires a lot of prior knowledge...
Secondly, there is also the question of what it actually means to be differentially expressed between tissues. Transcripts (and/or their corresponding products) hardly ever function on their own. They interact with the rest of the transcriptome/proteome, causing feedback to gene expression etc. These "backgrounds" are drastically different between cell types. Also, the same amount of mRNA may lead to different amounts of protein depending on the status of the cell (presence/activation of ribosomes, tRNA,...). As a result, the impact of a change in the number of copies of a transcript may be enormous in one tissue, versus negligible in the other.
These are actually considerations that to a large extent hold true even when comparing gene expression between conditions in the same tissue, but obviously the more different your samples are to start with, the more exaggerated the effects will be. So, my two cents is: be careful, it's a dangerous comparison. I would rather try healthy lung vs lung cancer and healthy skin vs melanoma.
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Hello Everyone,
I have just started to work with animal cell culture studies. I am working on certain novel tyrosinase inhibitors as skin whitening agents. Almost all the literature survey I have done is using B16F10 cells for inhibition assays. I have SK-MEL 31 cell lines which is also melanoma cell line but from human source. I didnt come across with papers using SK-MEL lines for tyrosinase or melanogenesis inhibition. I wonder if I can use SK-MEL 31 for the same experiments.
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Thank you for the valuable response.
I am also using enzymatic activity measurement with mushroom tyrosinase but i need to do western blot analysis on melanogenic pathways. I obtained B16F10 cell lines, now I am moving with them.
Regards
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I tried to thaw several stocks from the -80 freezer that date back to one year and others from liquid nitrogen that date back to two years but they die continuously. I thaw them in 6-cm culture dishes but they are very weak and very slow. I waited for so long until one plate became confluent and then splitted it in two 10-cm plates. When they were passaged they became even weaker and every day I look at them, I find a lot of floating cells and nothing improves when I change the medium. N.B. I culture them in DMEM with 10% FBS.
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In addition to all replies above, new stock of FBS might be the culprit. Some FBS stocks don't seem to work for some cell lines. 2.
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I have used the common ABCD features for melanoma classification. However I want to explore some more suitable features. Could anyone help me?
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Creo que esas serian las mejores
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Papers related to Melanoma Skin cancer using Image processing and the latest methodology being Incorporated to identify the Cancerous cells?
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We are doing a anti tumour activity by expressing a gene through AAB DJ8 (Cellbiolabs).
Weirdly we see anti tumour activity in even in control AAV GFP vectors! We are using the Melanoma xenograft model and the AAVs are injected via the tail vein.
We don't purify the vectors as such; we have extracted the viruses using freeze thaw in presence of benzonase. Further we pass the extract through 0.45 filters and its resuspended in PBS.
Pls. free to ask me more questions if needed.
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Because you mentioned that you did not purify the AAV virus, but simply freeze-thaw and filter it, then you of course got a lot of cell fragments and media components in AAV crude extract. Purified AAV viruses produce only very low immune responses and other side effects, according to current reported studies and clinical trials. But if you used a cude extract, tt is bound to induce very strong immune responses in mice,even just use a AAV-GFP control, which maybe the reason for the observed anti-tumour activity. Maybe you inject a freeze-thaw cell lysate, you would got the same result. I strongly suggest you to purify AAV with ultracentrifuge followed by dialysis. Hope these can help you.
You could find more information about AAV production and application in this website: https://www.genemedi.net/i/aav-packaging
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I’ve just made results of immunocytochemistry with B16F10 melanoma cell (1st antibody: anti-Sox10/ 2nd antibody: Alexa 488 green) and then I got total 7 images which are observed by optical microsope, DAPI, Alexa 488green, DAPI+Alexa488, optical+DAPI, optical+Alexa, optical+DAPI+Alexa.
However, i’m not sure which image I should put on my paper. Is there anyone who can help choose typical result images for appropriate result of immunocytochemistry with nucleous protein??
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If you have at your reach a microscopy that allows you to detect fluorescence, you can show an image where the fluorescent signal of the cell nucleus overlaps the fluorescent signal of your nucleus protein (DAPI+AF488). In the supplementary file, you can include the control image.
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I am working with the B16-F10 murine melanoma cell line in C57BL6 mice. I have seen several different growth patterns after s.c. injection. Usually the tumors develop as small black dots and progress into round black tumors. I have also seen spreading black patches that don't develop into raised tumors. Recently I have also seen brown scab-like growth after injection. Cell prep and injection was the same in all cases; can someone explain the differences or has anyone seen similar growth patterns?
Any advice would be greatly appreciated!
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Exactly :) My pleasure, best regards, Przemek
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Dear Colleagues and Friends
I have faced a strange results in my previous experiment.
I had Melanoma cells in culture and after 4 days, I wondered when I saw that the melanoma cells were morphologically changed to a neuron like cells or more likely to melanoblast cells.
The most exciting part of this morphological changes, that prevent me to ignore, was that their growth have been stopped or significantly decreased without applying any specific/new chemicals.
So, I would like to know about any non-specific reason behind this phenomena.
Considering that, this morphological and metabolic changes were happened for a malignant/invasive type of skin cancer cells, the answer may results in a way to step forward in cancer treatment.
Best Regards
Behnaz Ghaemi
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A noticeable change in cell morphology that associated with a cell growth arrest often results due to sub-optimal cell culture conditions. These conditions include, a change in cell density, culture medium (growth factors), cell culture flask/plate (a change in extracellular matrix-induced signaling), and sub-optimal trypsinization of cells. Other conditions (the list is long) are also known to alter the cell morphology. Therefore, if you have notes from your cell culture conditions, it should be possible to identify potential factor(s) that might have contributed to your observations.
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I am currently looking for a working unconjugated antibody directed against human CD39 (ENTPD1) for immunohistochemical analyses on FFPE tissue (Melanoma).
Thank you for any recommendations.
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I'd recommend doing a search on BenchSci for published antibodies (https://landing.benchsci.com/academic)
Please see attached for more detail.
I hope this helps!
Maurice
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Actually we tried to develop a xenograft metastatic model of melanoma with NOD-SCID mice after ic injection of A375 metastatic melanoma cell line. After 4 wks by ic injection we only found oligometastatic disease, prevalently spread to bones or muscles. 
Are NOD-SCID mice suitable for this model?
Many other groups used Nude mice for the same purpose, however with different cell lines. We will soon repeat experiments with other cell lines.
Does anyone have experience with both NOD-SCID and Nude mice xenograft models of metastatic melanoma?
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We use NOD/SCID mice in our commercial A375 xenografts (http://altogenlabs.com/xenograft-models/melanoma-xenograft/a375-xenograft-model/) and they tend to work well, with stable growth curves as well. I would make sure your starting injection is done properly (we use matrigel with 1 million cells) and then monitor for any kinds of symptoms that wouldn't correspond with normal tumor growth.
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I want to find out if skin tatoo has any effect in skin cancer
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Hello,
I wondered this; these papers might be of interest:
Kluger, N. (2016). Cutaneous and systemic complications associated with tattooing. La Presse Médicale, 45(6), 567-576.
This is the ResearchGate link:
I have not seen the full text of this 2008 paper, but it sounds relevant:
Kluger, N., Phan, A., Debarbieux, S., Balme, B., & Thomas, L. (2008). Skin cancers arising in tattoos: coincidental or not?. Dermatology, 217(3), 219-221.
Kluger, N. (2009). Skin tumors arising in tattoos: coincidental or upcoming public health issue?. Expert Review of Dermatology, 4(4), 313-315.
Very best wishes,
Mary
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I need a commercially available or patient-derived melanoma in situ cell line for my research at MSKCC. Can anyone help me find one?
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HI Adi,
Hope you are doing well, you might contact MD Anderson Melanoma department for the cell line you seek. If you have requirement for any particular cell line let me know I would ask around.
Thanks
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I am looking for a method to stain spleen sections to identify germinal centers in mice.  What stains, antibodies, or protocols do you use to verify the identity of a germinal center?  Thank you!! 
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For staining naive B cells that are not in the B cell follicle, use anti-IgD; for germinal center B cells in the follicle, use anti-FAS(CD95), anti-GL7, anti-PNA, either two of those should work; for follicular dendritic cells in the light zone of germinal center, you can use PE-conjugated-hapten(NP) in vivo, or anti-CD21; for T cells, use anti-CD4.
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I could not found the cell sizes of some cancer types such as; lung (NCI-H2126, ATCC CCL-256), breast (UACC-1179, ATCC CRL-3127), over (EFO-27, DSMZ ACC-191), melanoma (A-375, ATCC CRL-1619), pancreatic cancers (PA-TU-8988S, DSMZ ACC-204).
Could you share your information?
Thank you for your help.
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CLSM observation method can be used to find the cell sizes of some different cancer types. CLSM images analyzed by the ZEN 2011 software can be offered scale bars automatically. You can utilize the scale bars to differentiate the different sizes.
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Dear all,
I try to get primary cells from my melanoma mouse. But I failed several times (cell contamination or cell not growing). So is there anyone do this experiment before? would u please tell me your steps or relevant papas. Thanks
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We used TG3 transgenic mice which are spontaneous development cutaneous melanoma. We want to get melanoma cells from this mouse line for further study.
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Cancer starts to occur with the disorderly change of healthy cells, which forms a mass known as a tumor. A tumor is of two types, Benign and Malignant. Malignant meaning that the tumor can grow and increase to other parts from the body whereas benign can grow but will not spread. The skin is the largest organ within the body, protecting against injuries and infections. Malignant melanoma is a very dangerous form of skin cancer with the largest number of incidents around the world. Early diagnosis quickly followed by its removal for malignant melanoma is very important for a patient to survive.
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I hope to clarify some of what you have written; most of it is correct, but there are some fundamental misunderstandings.
Most skin cancers do not spread and are not benign. Squamous Cell Carcinoma and Basal Cell Carcinoma, specifically know as Keratinocyte Carcinoma or generally referred to as Non-melanoma skin cancer are malignant, localized, seldom fatal, and are diagnosed more than every other cancer combined. Melanoma is very serious, but melanoma is not close to the largest number of incidents identified.
I'm not sure of the current status of publication, but I am aware of a person who purchased most of the apps available where they report the ability to distinguish benign vs. concerning features on the skin. The results are not generally favorable.
As someone who works with dermatologists while seeing patients, I am impressed with their ability to visually distinguish concerning growths from others. That said, it would seem teaching a computer to provide the same level of interpretation should be straightforward, but I have yet to see one that can outperform new dermatologists.
I hope that you are interested in this type of research and you are the person to develop the methodology to make visual identification accurate and reliable. I believe it is possible.
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Melanomas and sun related skin damages occur exponentially in the last decades. Primary care providers are the perfect professional group to screen the skin of patients.
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"The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of visual skin examination by a clinician to screen for skin cancer in adults." (in asymptomatic adults)
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I've been looking for weeks finding only the same papers and none of these actually state the medium they used.
I need this for my master thesis and I would be eternally grateful if someone could help me out here.
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Check out these two articles, they have very specific information regarding the cell culture media. Hope you can find what you are looking for.
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I am planning to do a very preliminary experiment using a few representative solid cancer cell lines. Probably Three for each cancer types.
For Breast cancer, I am thinking to use MDA-231, MCF7 and maybe one HER2+ cell line. Since my research before is all about hematological malignancies, I would like to ask the experts' opinions about which cell lines are the representative or most commonly-used ones for the aforementioned three cancer types. Thanks
Aaron
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For representative Melanoma cell lines, you should used melanoma cell lines mutated on BRAF (such as A375), NRAF (such as SkMel2), NF1 (such as MEWO) or "triple negative" (such as CHL1). Read this recent publications (Luebker-Oncotarget 2017) for details of genomic alterations in a wide range of melanoma cell lines.
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Approximately 30% of cancer patients respond to ICB therapy, some for very extended periods. ICB is an enormous step forwar for many cancers such as melanoma but still, the majority of patients do not respond or relapse after initial response. The discussion on this topi is hot and there is evidence for different causes of resistance. I would like to know your experience.
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Hi Ulrich, I would like to introduce you to the work of my colleague, Dan Adams, who is isolating giant cells from patient blood samples.
These cells bear the hallmark of both macrophages and megakaryocytes and are probably the tumor associated macrophages (giant cells) that pathologists described in biopsies decades ago.
They could be the missing link in the interactions of the immune system with cancer cells.
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Hi everyone!
Im running some experiments on melanoma cells and betulin.
Can you tell me please which solvent I can use to solubilized the betulin?
Many thanks!
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Hi. I'm trying to transfect my Malme3M and A375 melanoma cell lines with using the HiPerfect transfection reagent. However, I'm having trouble transfecting these cells. I use the AllStar Cell Death positive control from Qiagen to assess the efficiency of the transfection (the more dead cells, the higher the efficiency). However, the cells just won't die. I used siRNA concentrations ranging from 7.5 nM all the way up to 50 nM. I used 3 or 4.5 µL transfection reagent. To form complexes I incubate for 10min in 100 µL Optimem medium before adding. I use 20.000 cells in a 24 well plate.
Does anyone have an idea what could be the problem? Should I use a higher concentration? Or add more transfection reagent?
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