Science topic

Tumor Biology - Science topic

Explore the latest questions and answers in Tumor Biology, and find Tumor Biology experts.
Questions related to Tumor Biology
  • asked a question related to Tumor Biology
Question
3 answers
My experiment aims to make spheroids by sacrificial micromolding technique.
I am following the easy protocol:
"...The PDMS stamps were deposited onto a 250 μl drop of 3% liquid agarose within the wells of a 24-well plate. Agarose gelation occurred within minutes of placing the 24-well plate at room temperature..." Karen E. Samy, 2019.
The PDMS stamp has pillars with 120 um in diameter and 80 um in height according to the article.
However, the problem is, that during pull out of the PDMS stamp the bottoms or walls of agarose microwells are somehow stuck on the pillars, and they are pulled out with them. So, instead of having nice microwells, there are cones made out of pulled microwells, and the cells can't get inside and form a spheroid.
I have tried 3% agarose (according to protocol), 5% agarose, different timing, place the stamps with agarose to fridge or freezer for 10 - 20 minutes, used plasma on PDMS stamps to make them more hydrophilic and all these combinations together.
I am running out of any other ideas. Does anybody know, what could help my situation?
Unfortunately, the corresponding author hadn't answered.
The photo of the "microwells" is attached. In this picture, you see two successful microwells and poorly done the rest of them.
Relevant answer
Answer
Hello guys, thank you for your advice. However, it turns out that whole SU-8 wafer was made in the wrong way. There were missing another nanolayer of the certain chemical substance that makes it easy to remove PDMS from wells. In the first case, the residues of PDMS left in the holes. So now they adjust it and it is working well.
  • asked a question related to Tumor Biology
Question
4 answers
The investigation of suitable time point of T cell activation by specific antigen is the critical point to manage your real evaluation of T cell response of tumor antigens. Here, I am working on the Panc02 tumor lysate what is the experimental time points are useful to evaluate T cell activation response?
Relevant answer
Dear sir Dr
Helper CD4+ T cells
Helper T cells become activated when they are presented with peptide antigens by MHC class II molecules, which are expressed on the surface of antigen-presenting cells (APCs). Once activated, they divide rapidly and secrete cytokines that regulate or assist the immune response.📷en.m.wikipedia.org › wiki › T_cell
T cell - Wikipedia
  • asked a question related to Tumor Biology
Question
1 answer
I'm considering implanting OT-1 mice with OVA expressing tumors (B16-OVA) or E.G7-OVA).  Will these mice reject these tumors since a large fraction of their T cells are specific for OVA?  Does anyone know of any references for this type of experiment?  All studies I have seen use WT mice with adoptive transfer.  
Also are there any safety concerns for the mice, such as massive inflammatory response?  Thanks!
Relevant answer
Answer
Hi Michael, here is a paper may answer your question.
Adoptive T cell therapy promotes the emergence of genomically
altered tumor escape variants
  • asked a question related to Tumor Biology
Question
5 answers
Hi,
I am curious to know if it is possible to store tumors (or tumor tissues) isolated from mice at -4 degrees (frozen) in serum free RPMI or DMEM medium overnight or longer? I would like to FACS sort live cells later. The situation is such that I have to store the tissues overnight. Any insight will be helpful.
Thanks
Relevant answer
Answer
The main problem with freezing is ice crystal formation - the DMSO added to freezing medium helps to prevent that. It acts as a cryoprotectant. Without the DMSO, chances are good your cells will be damaged as ice crystals form both outside the cells and inside. If you're looking at whole tumors, by guess is that you'll have some live cells left in the center of the tumor, but experience significant cell death in the outer layer of tissue.
If you only need to store overnight, why not just store them in a refrigerator? It'll keep them cold, but not freeze them to death, and thus hopefully leave you with more cells to work with.
  • asked a question related to Tumor Biology
Question
6 answers
My lab is currently searching for a new human/mouse GLI2 antibody. We were using the sc-28674 from Santa Cruz and were quite satisfied with it, but it is no longer produced, so we tried the new sc-271786 from Santa Cruz and the ab26056 from abcam and both did not give satisfying results.
Relevant answer
Answer
I'd recommend doing a search on BenchSci and review published data for your best option (https://landing.benchsci.com/academic)
Please see attached for more info.
I hope this helps!
Maurice
  • asked a question related to Tumor Biology
Question
7 answers
Many genetic changes can immortalized cancer cells including oncogene activation or tumor suppressor gene inactivation. For example telomerase activation is one way to immortalize cells.
But what is the difference between mechanism of immortality in normal stem cells (NSCs) vs cancer stem cells (CSCs)?
Is there any different mechanism for maintaining genome stability in NSCs and CSCs?
Is there any literature that anyone can provide?
Relevant answer
Answer
Actually it is much more complex than just reactivation of the telomerase enzyme; sure that may cause immortality, but the complex pathology of metastasis via cancer stem cell relies on their ability to reactivate stem cell like patterns of gene expression. This allows them to migrate and reestablish a flawed developmental
program, i.e., a tumor at a distant site, eventually causing death.
  • asked a question related to Tumor Biology
Question
4 answers
I plan to evaluate cell death and ROS generation.
Relevant answer
Answer
Steve Mcclellan Hi Steve, Could you send me your old protocol for isolating viable cells after tumor digestion using collagenase/dnase.
Thanks a lot
  • asked a question related to Tumor Biology
Question
7 answers
hello,I am working on mouse tumor xenograft model of HepG2 (subcutaneous),now the tumor have began to grow,but i don't know the best time to initiate antibody treatment(the volume of tumor reach over 100mm3? if yes, why?if no,what? ) and the method to inject antibody(intraperitoneal or subcutaneous or caudal vein  injection? which one is the best and why?),calculate the volume of tumor by V=(L*W2)/2 . I am a novice, I will be grateful for any reponses.some paper related is also good. thanks in advance.
Relevant answer
Answer
We do HepG2 xenografts commercially (http://altogenlabs.com/xenograft-models/liver-cancer-xenograft/hepg2-xenograft-model/) and our standard procedure is to initiate treatment regimens when tumor volumes are around 100 mm^3. If your antibody is effective, then the growth curves will be substantially different, giving you good results. We use matrigel with one million cells, and that has worked remarkably well.
  • asked a question related to Tumor Biology
Question
5 answers
Hello,
I am trying to grow xenograft tumors with cells mixed with matrigel. I see that at the injection site, the gel sets and forms a bump. How do I measure the tumor growth accounting for the gel bump, that is while I am measuring tumor growth how do I differentiate between matrigel and tumors? I use caliper measurements for tumor growth.
Relevant answer
Answer
I agree with Roman about the volume of the injected mixture (100 microliters is a good starting point). Our xenografts (http://altogenlabs.com/xenograft-models/) are done with matrigel for the most part, and by the end of the study the growth curves are so clear that the initial volume of matrigel becomes insubstantial. As long as your growth curves have a relatively similar starting point, you'll have statistically significant results from an effective drug regimen.
  • asked a question related to Tumor Biology
Question
6 answers
How to calculate IC50 values to drugs that does not reach a 100% of inhibitory activity, for example? If I find a experimental value of 45% inhibition in the maximal concentration of solubility (for example 10uM), should I say that IC50 value is "higher than 50uM"? If one compound presents a inhibitory activity around ~60% at the highest concentration tested (total solubility), the 60% will be the "top" value to use to calculate IC50 ? thank you all!
Relevant answer
Answer
Hello Elaine,
I have encountered the same problem and came across your question. May I ask, what did you do in the end? Did you publish those results?
Best regards,
Tamara
  • asked a question related to Tumor Biology
Question
4 answers
I try to figure out some easy method to transfer spheroids from hanging drops from a petri dish lid into 96-well plates. So I had the idea to generate the tumor spheroids directly on the lid of a 96 well-plate directly instead of generating them on petri dish lids and to centrifuge the plate after spheroid initiation. Does that work to centrifuge the spheroids from the lid directly into the well? 
Relevant answer
Answer
Hi Ann,
I'm interested in your idea. Finally, did it works? Could you post your protocol?
  • asked a question related to Tumor Biology
Question
4 answers
We have BXPC-3 human pancreatic cell line which had mycoplsma contamination, we treated them with plasmocin for 2 weeks and now the morphology of the cells totally changed. They used to be polygonal and formed tight colonies at lower seeding densities, not they are spindle shaped and do not form colonies at all. We sent the DNA sample for authentication and it matched so there is no cross contamination with other cell lines and the mycoplasma result came negative, but the cells don't look like BXPC-3 anymore.
Please help us trouble shoot this issue.
Thank you very much!
Relevant answer
Answer
I have seen in my experiment that the shape and cytoplasmic projection of human cells had changed when the sterilized broth media of 24 h cultured pathogenic and non pathogenic bacteria were added.
  • asked a question related to Tumor Biology
Question
3 answers
Is anyone working on the pathological and/or molecular characterization of very aggressive breast cancer beyond "triple negative" definition?
Relevant answer
Answer
Dear Sir,
You can try with the expression level of cell surface marker such as CD44+/24-. Also, you can try with EMT markers. 
In my work, I am using these CD44+/24- marker. Cells having these markers are very aggressive and metastatic. (aggressive for triple negative and non-triple negative too)
Regards,
Utsav
  • asked a question related to Tumor Biology
Question
2 answers
Dear Community,
checking billion of resources, apart from B16 cells, Im not able to find any clou for another murine melanoma cell line.
DOES ANYBODY KNOW SOMETHING or has an idea/tipp?
I would highly appreciate that!
Cheers,
Michi
(P.s: best would be, coming from any WT (e.g. BL6) background)
Relevant answer
Answer
Thank you!
The search for a spontanous mela cell line (not ex vivo gen. modified) is not that easy ^^
  • asked a question related to Tumor Biology
Question
1 answer
What is Positive control Ehrlich ascites tumor?
Could be Cisplatin?
Relevant answer
Answer
We used Bleomycin as the positive control for EAC (Ehrlich Ascites Carcinoma) cells.
Look in our paper-
Cheers 
  • asked a question related to Tumor Biology
Question
2 answers
Hi, I am planning to isolate single cells from human lung tumour tissue. I am wondering what is the best way to enzymatically degrade the tissue to isolate MOST of the cells (since the population of interest is very rare and I want to avoid false negatives when I do FACS analysis). I came across multiple collagenase cocktails which have been reported in literature, but not sure which is the best way forward. Which is the best collagenase to work with?
Any leads would be appreciated. I don't want to optimise too much since these are precious patient samples. Thank you! :)
Relevant answer
Answer
You can digest tissue in RPMI-1640 (2-3% serum) containing 0.8mg/ml Dispase and 0.2mg/ml Collagenase P (Roche). Tubes should be incubated at 37˚C in a water bath or incubator and gently invert at 5-10 min intervals to ensure the
contents are well-mixed. After 30 min,gently collect the cells in another tube and add the fresh media with collagenase and dispase. Total process will take around 60 min. Centrifuge the cells and plate them in fresh media.
  • asked a question related to Tumor Biology
Question
1 answer
Many papers either do not specify the type of MatriGel (HC, GFR, phenol free, etc) or apparently do not use it for orthotopic implantation at all. Anyone use Cultrex as an alternative? Thanks in advance for the insight!
  • asked a question related to Tumor Biology
Question
2 answers
Hi all,
My research is about macrophages in breast cancer,so I have to separate TAM from tumor. I've tried several methods:mechanical digestion,enzymatic digestion.However,after making single cell suspensions from breast tumor,I don't know how to select TAM from cell suspensions.As the literatures say,1)magnetic bead-conjugated antibody cell isolation;2)density gradient separation;3) laser capture micro-dissection;4)FACS;
I hope you could give me some suggestions on separate and purify TAM from human breast tumor.Thanks a lot !!!
Relevant answer
Answer
I would go with option number 1 from your literature, selecting for CD14 or CD11b or CD68 positive cells. By gradient centrifugation you would still have a lot of other cell types coming along.
  • asked a question related to Tumor Biology
Question
2 answers
Currently I'm studying the cytotoxicity of metal complexes in 2D cell cultures, but at some point I would also like to go to tumor spheroids as they are closer to tumors in vivo. We use the SRB assay to determine cytotoxicity in 2D and in order to compare the results from the 2D and 3D culture I would like to use the same cytotoxicity assay. However I cannot seem to find any papers where the SRB assay is used to determine cytotoxicity in tumor spheroids. Can somebody tell me why this method is apparently not suitable to use in tumor spheroids? 
Relevant answer
Answer
I think we can use SRB assay for tumor spheroids too.
  • asked a question related to Tumor Biology
Question
7 answers
We've been using the MC38 s.c. tumor model and continue to have issues with tumor ulceration. We have tried injecting in different locations, varying the cell number, varying the resuspension buffer (PBS, RPMI, matrigel), using different cell lots, etc. The cells are myco-free and have been MAP tested. This is not a tumor size issue as the ulcers appear in small tumors (~200 mm3).
Has anyone had success in reducing the ulceration frequency?
Relevant answer
Answer
Ashleigh,
Thanks for the comments. I, too, am amazed by publications with this model. How can they 'realistically' and 'accurately' measure such tumors with large holes in them?  
  • asked a question related to Tumor Biology
Question
2 answers
I have interest in monocyte-macrophage lineage and examining the behavior in the TME.
I know that MDSCs can be granulocytic or monocytic, but do monocytic MDSCs represent the same or an overlapping group as TAMs?
Would love both a verbal description differentiating their behavior and the flowcytometry markers used to distinguish/define them if possible.
Finding it very hard to distinguish from the literature due to inconsistencies in cell markers and terminology.
Relevant answer
From my experience with mouse MDSC and TAMs.
I think MDSC are well defined by markers as CD11b+GR1+ or CD11b+Ly6Chi. There are others makers in the literature but among all of them, I think these represent a good putative choice. Besides, TAMs, are a bit more complicated to get them. Surely, the marker CD11b overlaps between both populations but there are more specific markers from the alternatively (M2) activated macrophages that are not linked to MDSC. An example are the following; CD163, Arg1, Ym1 or Fizz1. 
  • asked a question related to Tumor Biology
Question
1 answer
Dear All,
I am currently trying to establish cell line for canine cutaneous epithelial tumors (hair follicles in origin). For primary cultures, I followed the standard protocol using 10% FBS in DMEM containing 1%Penicillin-Streptomycin. I subcultured it using the same media as above. At P3, I performed immunocytochemistry and found that most of my tumor cells were strongly positive for vimentin and nestin but showed very pale positivity for pan-cytokeratin. The secondary cell line did not survived until the fifth passage (I tried twice but the cell stop growing and started dying at around 5th passage). The DMEM contained: 4.5 g/L D-glucose, L-Glutamine and 110 mg/L Sodium Pyruvate. I had look into some journals reporting the establishment of squamous cell carcinoma cell line which used 3T3 Feeder Layer, cholera toxin and hydrocortisone. I would like to ask if anyone can share their experience in culturing tumor cell lines of epithelial in origin and the basic growth supplements and suitable media required for successful cultivation of epithelial tumors. Thanks a lot !
Relevant answer
Answer
Hi Mun,
I am currently culturing 4T1 cells, a murine mammary carcinoma line that displays both mesenchymal and epithelial characteristics. The media I have been using with much success is RPMI based, supplemented with 10% FBS, 100 U/ml penicillin, 100 μg/ml streptomycin, and 2 μM L-glutamine. I have been subculturing at roughly 70% confluency in a T-25 flask and seeding the cells at 250,000 cells/flask.  
Hope this helps!
  • asked a question related to Tumor Biology
Question
5 answers
Neurotransmitters have been shown to drive tumor progression in the prostate glands and the stomach. In particular, it has recently been shown that acetylcholine promotes proliferation of Lgr5-positive cancer stem cells via the modulation of YAP-dependent canonical Wnt/beta-catenin signal pathway. Then the secretion of NGF occurs. This forms the positive feedback machinery. Is there any clinical method to demonstrate the denervation in the tumor tissues?
Relevant answer
Answer
Denervation suppresses gastric tumorigenesis
Chun-Mei Zhao,#1 Yoku Hayakawa,#2 Yosuke Kodama,1 Sureshkumar Muthupalani,3 Christoph B. Westphalen,2,4 Gøran T. Andersen,1,5 Arnar Flatberg,1 Helene Johannessen,1 Richard A. Friedman,6 Bernhard W. Renz,2 Arne K. Sandvik,1,7Vidar Beisvag,1 Hiroyuki Tomita,8 Akira Hara,8 Michael Quante,9 Zhishan Li,10 Michael D. Gershon,10 Kazuhiro Kaneko,11 James G. Fox,3 Timothy C. Wang,2,† and Duan Chen1,†
 
Go to:
Abstract
The nervous system plays an important role in the regulation of epithelial homeostasis and has also been postulated to play a role in tumorigenesis. We provide evidence that proper innervation is critical at all stages of gastric tumorigenesis. In three separate mouse models of gastric cancer, surgical or pharmacological denervation of the stomach (bilateral or unilateral truncal vagotomy, or local injection of botulinum toxin type A) markedly reduced tumor incidence and progression, but only in the denervated portion of the stomach. Vagotomy or botulinum toxin type A treatment also enhanced the therapeutic effects of systemic chemotherapy and prolonged survival. Denervation-induced suppression of tumorigenesis was associated with inhibition of Wnt signaling and suppression of stem cell expansion. In gastric organoid cultures, neurons stimulated growth in a Wnt-mediated fashion through cholinergic signaling. Furthermore, pharmacological inhibition or genetic knockout of the muscarinic acetylcholine M3 receptor suppressed gastric tumorigenesis. In gastric cancer patients, tumor stage correlated with neural density and activated Wnt signaling, whereas vagotomy reduced the risk of gastric cancer. Together, our findings suggest that vagal innervation contributes to gastric tumorigenesis via M3 receptor–mediated Wnt signaling in the stem cells, and that denervation might represent a feasible strategy for the control of gastric cancer.
  • asked a question related to Tumor Biology
Question
5 answers
I am setting up an experimental metastatic model of Lewis lung carcinoma by intravenous injection of LL/2 cells into the tail vein. I am looking for ways to quantify tumor burden in the lungs.
I understand that using Luciferase/fluorescence expressing cell line is one way to detect tumor cells in the lungs, however, I am looking for something more specific, perhaps a marker expressed in these tumor cells which would increase with tumor progression (For e.g. for B16F10 cells, I am using a melanocyte specific gene and study tumor burden using RT-PCR). 
Thanks for your suggestions!
Relevant answer
Answer
If you want to achieve it a little bit easier, you apply  e. g. the point counting method according to E.R. Weibel, but also for this method the sampling procedure is essential (see morphometry / stereologyof the lung).
  • asked a question related to Tumor Biology
Question
3 answers
We have been trying to develop 4T1 breast tumor model in balb/c mice. We have been injected 10^6 4T1 cells suspended in 100 uL PBS into the mammary fad pad region, subcutaneously. After 10 days we see mass, in site of injection. The size of mass is approximately 5mm ×5 mm. After 20-days mass is completely regressed in some mice and in some other the size of mass aggressively diminished. in pathological examination, some of the small mass have tumor properties and are malignant. if these mass are tumor what are the causes of restricted or abolished growth of them? why these cell line can induce small tumors in some balb/c mice but not in all of them?
Relevant answer
thanks, dear Sajid for your practical advices.
  • asked a question related to Tumor Biology
Question
10 answers
I am working with adaptively transferring leukocytes in tumor-bearing mice. So I am taking the cells from the donor animals, label them with fluorescent dyes and inject them back to the recipients. However, because of all the unnecessary damages that labelling of the cells in vitro causes, I am looking for a way to label the neutrophils in vivo
Currently I am planing to label the monocytes in vivo so I am also thinking to label the neutrophils as well in different settings.
Moreover, I wondering when I label the circulating blood monocytes in vivo how many monocytes I can label and how many of them actually migrate to the tumor xenograft!
Relevant answer
Answer
BM will give you macrophages.  M-MDSCs are found in low numbers in the spleen and other organs.  We were never able to get enough to study bio-distribution.  To get around this problem we labeled total spleen cells and used flow to identify who went where.  However, still not enough M-MDSCs to track.  We found you needed about 10e7 labeled cells to track over time.  The use of CSFE lets you follow cell proliferation as well. 
  • asked a question related to Tumor Biology
Question
2 answers
Is there any metabolic similarity and glucose dependencies? We published on this in the past, but are curious if their metabolism is also alike.
Thanks
Mannan
Relevant answer
Answer
Dear AbdulMajid,.
That's my paper, we published it Alhamdolliliah.
Best 
Mannan 
  • asked a question related to Tumor Biology
Question
6 answers
I am looking for immunocompromised mice to grow human tumor xenografts in. I am potentially interested at looking at macrophage function in these tumors. Is there any mouse model that will give me the best of both worlds by allowing my tumors to engraft while having normal macrophage numbers/activity/function ?
Relevant answer
Answer
Hi Matthew,
You can use NOD/SCID mice. The macrophage function is not normal but not absent as well. It's just interrupted or delayed therefore you can try this well established animal model for xenografts.
All the best
  • asked a question related to Tumor Biology
Question
1 answer
Thank you
Relevant answer
Answer
Hey Siegel,
You can use this:
Starting material: Tissues stored as chucks under liquid nitrogen.
During handling the material is kept on ice. Before generating a lysate, the tissue is first cut into ~1mm cubes by using a razor blade on a glass plate held on ice.
The small cubes are then transferred into a hand held potter homogenizer with three ml ice-cold RIPA buffer per gram of tissue.
 Tough tissues like Prostate, Skin and Thyroid need incubated in the RIPA for 20
min on ice before starting homogenizing
 Medium tough tissues like Colon, Duodenum, Heart, Kidney, Skeletal Muscle or Tonsil, are kept in RIPA on ice for 10min before homogenizing
 Homogenize by pushing the piston slowly into the mix by continuously twisting the wrist thus turning the piston around its axe.
 Make sure all tissue chunks slide between the piston and the glass wall while homogenizing.
 Once the piston reaches the bottom, reverse the handling
 Keep the tissue submerged in the ice during the process
 Repeat the cycle until the tissue is liquefied
 Divide the liquefied tissues over 1.5ml tubes and centrifuge at 13,000rpm for 3 min at 4C
 Transfer the clear supernatant in new clearly labelled tubes. Take 20ul out for protein determination
 Protein determination is carried out using the BioRad Protein Determination Kit.
 Adjust the lysate to 5mg/ml by adding ice cold RIPA buffer
 Store in liquid nitrogen.
RIPA buffer: 20mM Tris-HCL pH7.4, 150mM Na\Cl, 1mM EDTA, 1% Triton-X100, 1%
sodium deoxycholate, 0.1% SDS with freshly added PMSF to 1mM and with freshly
added aprotinin and leupeptin to 5ug/ml just before use.
All the best.
  • asked a question related to Tumor Biology
Question
2 answers
Hello, what  I want to ask: How do you decide which area of the tumour ist the best for counting? How do you go on with, if there in one slide  are areas without any signals, for example good signals in the periphere and no signals in the center ? How do you  interpretate, if there are only green ( control ) signals , is it loss of 1p or 19q, or will we have to do it again ?
Relevant answer
Answer
Thank you very much for your answer.
I think, it  will help us a lot in our diagnostic.
  • asked a question related to Tumor Biology
Question
5 answers
I want to get any protocol to treat ameloblastomas
Relevant answer
In Malaysia, we have Clinical Practice Guidelines (CPG) developed in 2015, which serves as a guide for us in managing ameloblastomas. You may have a look in the attached file.
  • asked a question related to Tumor Biology
Question
5 answers
I have found mixed messages in published articles around the likelihood that a primary (non-metastatic) vertebral tumor (i.e. extradural tumor) is benign.
"Metastatic tumors are most common (97%) tumors of the spine." Ciftdemir et al (2016) W J Orthopedics 7:109-116
"Primary extradural tumors of the spine are rare and constitute approximately 4% of all spine tumors." Lam et al (2014) SNI 5:S373-S375
"Benign tumors such as meningiomas and neurofibromas account for 55 to 65 percent of all primary spinal tumors... Metastatic spinal tumors are the most common type of malignant lesions of the spine, accounting for an estimated 70 percent of all spinal tumors." AANS (http://www.aans.org/Patient%20Information/Conditions%20and%20Treatments/Spinal%20Tumors.aspx)
What is the truth? Do metastatic spinal tumors make up 70% or 97% of spinal tumors? What is the likelihood that a primary vertebral (extradural) tumor is benign? 20% or as little as 01.2%? This difference is far from trivial.
Relevant answer
Answer
1. "Extradural" is a descriptor for lesions in the spinal canal. This is outside the spinal canal, in the vertebral body.
2. Likelihood odds and Bayesian analysis (of which I am a fan) work only that far; at some point one needs to "fish or cut bait" decisionally speaking: I.e. Do something with the probability numbers. That something, in this case, is probably a biopsy or do nothing.
3. I'd say the lesion is not a hemangioma. A subtle fracture or infection are possible. A primary tumor or the vertebra is less than 1%. A metastasis is possible but not likely .( hystory and presence or absence of lesions at other sites (bone scan) could help. Lymphoma is a distinct an important possibility because of prognostic and treatment implications.
4. This is ONLY one image, of one of the imaging studies, of a whole patient with history, clinical context, etc.; very little information for a decision.
I'd be curious what the physician ordering the MR advised. If you want to talk about it, call me in Skype or WhatsApp
Andrei Vermont
  • asked a question related to Tumor Biology
Question
2 answers
p21KO mice: does anyone have access to them and would like to collaborate?
Relevant answer
Answer
Thanks Rainer! Yes, i found someone in Spain willing to collaborate on this, so all good. But thanks anyway for your kind reply!
  • asked a question related to Tumor Biology
Question
3 answers
Cancer cells transferred by blood from one organ to another within  the metastatic cancer patient. This means that tumor cells are freely moving in the blood during the metastatic phase. If this cancer patient donates blood to another, there is a possibility  that the cancer cells transferred to the recipient  especially if the recipient is immunocompromised is this TRUE or NOT.  
Relevant answer
Answer
The short answer is no, they can't, given that they will generate a very strong immune response in the recipient. Even in immunocompromised (IC) patients the time required for few blood cancer cells to give rise to a full-blown cancer is typically very long, so only a very severe and long lasting IC could lead to cancer. In this context however, the chances of getting cancer simply because of the severe IC will be much higher than those of getting it due to blood donations. In the SCANDAT (Scandinavian Donations and Transfusions) database there was no evidence of increase in cancer risk among recipients of blood from "precancerous" donors i.e. from donors that later on were discovered to have cancer. It is also true however that cancer can be transmitted after transplant of solid organs, which suggests that the global number of 'transplanted' cancer cells and the subsequent immunosuppression therapy required to avoid organ rejection are also a critical factors.
  • asked a question related to Tumor Biology
Question
4 answers
Has anyone used NF639 cells to grow sub cutaneous tumors in FVB or Balb/C mice?
Relevant answer
Answer
nf639 dreived from mammary tumor of transgenic female mice of MMTV Model carrying the ERB oncogene.  I  worked once with the FVB Tg mice which are suitable for your desire experiment. 
this is the stock number from Jackson labo. 
002376
i hope im helping 
good luck 
  • asked a question related to Tumor Biology
Question
1 answer
From what I understood is that the granulin protein has a role in the growth of the tumor to neighboring organs. I'd like to know more information about it to see if it's possible to inhibit it and prevent it from spreading.
  • asked a question related to Tumor Biology
Question
8 answers
What should I do before mouse experiment?
Relevant answer
Answer
A metastatic process is a 3D process occuring in an amazingly complex tumor microenvironment.
Any cell migration / invasion assays relating to "pure cancer cells forced to evolve in 2D dimension and prisoners of closed plastic dishes" have nothing to do with the actual 3D journey of metastatic cancer cells.
Here attached are various in vitro approaches that recapitulate some of the important aspects of an actual metastatic process.
Best regards
PS: I also added 3 reviews for those of you who would be interested by the metastatic journey. These are the first three articles here attached.
  • asked a question related to Tumor Biology
Question
3 answers
Although gall bladder and bile ducts are lined by similar biliary epithelium, what is the reason for such a aggressive behavior and biology of gall bladder cancer as compared to cholangiocarcinoma? 
Relevant answer
Answer
Essentially they are different epithelium, even grossly appearing so.
In the pancreatico biliary system, there are at least 4 distinct epitheium:
  1. Bile duct
  2. Gallbladder
  3. Pancreatic 
  4. Ampullary
Our characterization of them morphologically seems simplistic at best, and one could expect additional division in the future.
Yeaton P, Kiss R, et al. Multiparameter digital image analysis of biliary, ampullary and pancreatic adenocarcinomas. Modern Pathol 1995;8:843-7
It remains an old story, as yet untold
  • asked a question related to Tumor Biology
Question
9 answers
I measure tumors in thigh (mouse). I usually use a vernier but i find it somehow subjective. Tumors are not always perfect round wich makes it difficult, is there something else that might be helpful that eliminates subjectiveness?
Relevant answer
Answer
Hi, Isaias. Using a caliper (vernier) is the fastest and cheepest way. To incease the precision, you could measure the three dimensions of the tumor and use formula V=0.5236(LWT) to calculate the volume (http://www.ncbi.nlm.nih.gov/pubmed/24682747). You could also wieght the tumors to assess their density. Computerized MRI would be the most precise method, but it is expensive and labor-consuming. 
  • asked a question related to Tumor Biology
Question
4 answers
Do we need biological markers in the management of PCa?
Relevant answer
Answer
 I would go for multi-modal MRI, mostly diffusion and T2 weighted imaging if it is active surveillance.
  • asked a question related to Tumor Biology
Question
5 answers
Hi there,
I would like to do a tumor burden follow-up by measuring circulating cell-free DNA (ccfDNA) at different time points in a mouse experiment (by treating or not mice after tumor initiation).
Does someone have a protocol to amplify DNA as I can draw only 100-200µl of blood/week in mice.
I have a protocol to isolate DNA (QIAmp DNA blood mini kit) from plasma.
Thanks in advance!
Christophe
Relevant answer
Answer
Thanks a lot Paul, I'll come back to you when I would have time to retry it!
  • asked a question related to Tumor Biology
Question
4 answers
Can a tumour secrete a product but not expressing the protein?
E.g: Negative CE expression but serum marker CEA is high?
Thanks
Relevant answer
Answer
oh great answers .... :) thank u
  • asked a question related to Tumor Biology
Question
3 answers
Does anybody have an experience in difference between PET / CT scanning of mice tumors with  a scanner designed for animals and humans?
Relevant answer
Answer
The CDTN and UFMG, Belo Horizonte -Brazil (Centro de Desenvolvimento da Tecnologia Nuclear and Universidade Federal de Minas Gerais) has animal PET  ,and humans PET-CT , you may wish contacting them       http://estatico.cnpq.br/programas/inct/_apresentacao/inct_medicina_molecular.html
Best regards,
Priscila Santana
  • asked a question related to Tumor Biology
Question
4 answers
e.g. Continuous trauma in one quadrant of the mouth of five cases causes a tumour to grow in that very quadrant, while for another five cases the tumour grew from a seperate quadrant than the one where trauma happened. So if I want to establish that the site of exposure is correlated to the site of tumour or vice versa, how do I do it ?
Relevant answer
Answer
I agree with Pierre.  For the most part, cancer is systemic and not the result of a localized exposure.  Exposures (diet, smoking, toxicants, etc.) that play a role in cancer initiation can cause both local and systemic epigenetic changes that influence the microenvironment. These exposures also cause inflammation.  Even in cancers that do not stem from inflammatory disease, inflammation is almost always present. However, if you are creating a local exposure and getting cancer both in that quadrant and in another, then, in addition to inflammation and inflammatory cytokines, there may also be epigenetic changes.  Everything in the body is connected, so the epigenetic changes aren't necessarily going to stay within the boundaries of the quadrant you have designated.
  • asked a question related to Tumor Biology
Question
8 answers
I already tried manually dissociation as well as GentleMACS but both are not working well with my frozen breast tumor tissue. I would like to do flow-sorting of single tumor cells afterwards! Thanks for all comments!
Relevant answer
Answer
My paper coted second one above... will give you insight regarding many protocols.. if you still need help let me know.
Regards
  • asked a question related to Tumor Biology
Question
1 answer
Macrophage can engulf tumor cell , in some case to kill it but sometimes it's a good way to help tumor cell to live and metastasis. So, How to distinguish a macrophage engulfed tumor cell is dead , alive or dormant?
Thank you!
Relevant answer
Answer
Macrophages in the tumor tissue is generally considered to undergo "education" not to engulf tumor cells but to cause chronic inflammation to promote metastatic migratory behavior of tumor cells. Dormant cancer cells (G0 phase) are likely to evade from immunity system by erasing the surface MHC molecule. 
  • asked a question related to Tumor Biology
Question
2 answers
I was looking in the literature for prostate cancer C4-2 cells (CRPC) mouse xenografts that used enzalutamide, but I wasn't able to find any such papers. Could any of you help me with this? Thanks in advance. 
Relevant answer
Answer
Thank you very much. I greatly appreciate your help.
  • asked a question related to Tumor Biology
Question
1 answer
Hello
I'm working on melanoma tumors from mouse and I want to extract proteins from it. I have a protocol where the detergent used is 10% Brij.
Is the concentration too high ?  Or is it normal because it's from the tumor and not from cells ?
Thanks for your help
Relevant answer
Answer
Hi Camille, 
I always used the RIPA buffer with 1% Triton X-100 in the 1X lysis buffer. Both Brij and Triton X-100 are non-ionic detergent, thus I suggest you to add your compound at a lower concentration. 1% is suggested as final concentration in most of the lysis buffer recipes. To increase the ionic strength, add 1% sodium deoxycholate (final) in your lysis buffer. I don't think is a matter of the tissue you're working with. Usually, mouse melanoma tumors (e.g. from B16 cells) smashing easily just pipetting. Good luck!    
  • asked a question related to Tumor Biology
Question
3 answers
Relevant answer
Answer
 Since the tumor is growing in 30-40% of your mice, I suggest that you extract the growing tumor from one mouse, expand cells in lab for few days, then reinoculate in large number of mice. also you can use these cells for next inoculation instead of the original cell line. I did that and it works
  • asked a question related to Tumor Biology
Question
2 answers
Can someone suggest a genetically modified spontaneous mammary tumor /chemical induced carcinogenesis model where genetic modification should result in significant alteration in glucose metabolism in mammary epithelium!
Relevant answer
Answer
Thank you very much.
  • asked a question related to Tumor Biology
Question
8 answers
I want to obtain tumor supernatant by culturing cancer cells in FBS free media. Right now my cells are in 10% FBS. Should I change the media directly to 0% FBS or reduce it gradually like 10%, 5%, 1%, then 0% so that the cells can adjust well in reduced serum? Please suggest.
Relevant answer
Answer
Hi Papiya,
actually I was even a little bit more cautious, and reduced it by 10%, 5%, 2,5%, 1% and then 0%. I have never tried a "normal" media without any FBS for a longer time, so I changed simultanously the media to one of the "serum-free"-media. 
Actually, if you need a lot of cell culture SN, you could first slowly change "your" medium to a serum-free media, first with the normal amount of FBS, I changed from 25%-50%-75%-100% always with 24 h between  Serum-free Media (always controlling the cell morphology; and always with FBS). Then reducing the FBS gradually.
If you don't need so much SN, just reduce the FBS gradually (always controlling cell morphology and cell attachment) and after a "short time" without FBS (I would recommend not more than 12 h, I have used 6 h) harvest the SN.
Carsten
  • asked a question related to Tumor Biology
Question
1 answer
Hi,
I am estimating the mutation rates (mutations/Mb) in a series liver tumors. How can I estimate the confidence interval of each mutation rate? I tried using the binomial test (binom.test function in R) but it is quite computation intensive...
Any better idea?
Thanks you very much in advance,
Eric
Relevant answer
Answer
Hello
Read this article ( Methods for Determining Spontaneous Mutation Rates ) by Patricia L. Foster , Where describes the proper design of a fluctuation assay, several of the methods used to calculate mutation rates, and ways to evaluate the results statistically.
  • asked a question related to Tumor Biology
Question
5 answers
Patients suffered from insulinoma have clinical feature of hypoglycemia.Insulinoma secrets insulin without control.What's the possible mechanism?
Relevant answer
Answer
Guo,
Normal beta cells contain glucose transporter 2 (Glut-2) and Glucokinase (GK). Both of these proteins have high Km (in the range of 13 - 15mM). Insulinomas tend to have Glut-1 and hexokinase, both are low Km versions. Transport of glucose into normal beta cells followed by its phosphorylation to Glucose-6-phosphate (the first step in glucose metabolism) is therefore dependent on the concentration of glucose in physiological range, whereas in the case of Glut-1 and hexokinase in tumor cells, even at the fasting glucose levels (3.5-5.5mM), the activity of these proteins is at their maximum level. Glucose metabolism, ultimately generates signals that are used by the cell to secrete insulin. This is why the insulinoma cells are always pumping out insulin at their maximum or near maximum levels even at 2 or 3mM glucose, which results in hypoglycemia. 
  • asked a question related to Tumor Biology
Question
3 answers
We are setting up a tumor model, injecting B16F10 into B6. Many people use simply PBS for the injection. I wonder if there is a preferred site of injection (flank, back, scruff, belly)? We are concerned that upon injection into the flank, the PBS solution does not stay put long enough (e.g. bleb seems to disperse fairly quickly).
Relevant answer
Answer
The B16F10 melanoma sub-cell line (from the B16 model) is usually employed to set up "pseudometastatic models".
If you inject the B16F10 cells into the tail vein, you will have the development of marked lunh "pseudometastases" (see the attached article by Mathieu et al., 2007).
If you inject the B16F10 cells into the carotid, you will have the development of brain mets (see the second attached article).
For subcutaneous model, you should graft the cells "on" the flank and not "into", otherwise you will have an i.p. model that will rapidly "destroy" the mice.
You can also use the B16 model for s.c. grafting but it is necrosing a lot (see Darro et al., 2005, here attached).
You should contact my colleague Véronique Mathieu, MD, PhD at vemathie@ulb.ac.be (she is unfortunately not registered on RG ...). She can help you with "some important details".
Best regards
Robert
  • asked a question related to Tumor Biology
Question
3 answers
Apart from the subcutaneous tumour, is the lung tumour also primary or metastatic? If metastatic, does it still represent actual lung tumour?
Relevant answer
Answer
Dear Riva,
Here attached you have three articles about the LLC model.
One article was "already" published in 1974 in the excellent journal Cancer Rwsearch.
A second attachd article shows a nice study using this model and published in PlosOne, which is a good journal.
A third article is a recent review and shows that the LLC model is often use.
There are ~4,000 publications with the LLC model in the PubMed database ...
I would not be too anxious with the LLC model ...
Best regards
Robert
  • asked a question related to Tumor Biology
Question
4 answers
Stereotactic Intracranial injections are extremely time consuming (Can only do 10-12 animals in a full day), are expensive- requires purchase of drill, dissecting scope, stereotactic apparatus, automatic fluid injector. Since many papers use different brain locations for injection of tumour cells and there is still significant error due to brain curvature etc., the exact location of the injections may not be crucial.
Meanwhile, guide screw injections are considerably faster and cheaper- only requires the drill, the accessory screw pieces and perhaps a dissecting microscope. It would also be much more practical for the sake of performing injections in large cohorts. This technique has been used in many high impact publications, particularly Zhang, 2015 in Nature (Exosomes PTEN Brain metastasis paper).
The flaw with this technique are that they are less precise than stereotactic injections, and this may lead to larger variation in tumour growth between animals. However, for the above stated reasons, I am wondering if it is worth the gamble.
Does anyone have experience with the guide screw technique, or both techniques that can provide input?
Relevant answer
Answer
Hello,
I do not have experience with work with tumor cells. However, I have almost 30 years of experience doing rodent surgeries. With respect to recovery of the rats or mice, the neurochemical environment, neuronal cell types, and glial cell types, there is a large degree of variation from one brain region to the next. For example some regions of the brain have proliferative zones and others do not. If one were to hope for refined answers to their questions, it seems like a very good idea to track the precise location/region into which you injected each time. There will be far more precision using stereotaxic injections. The Nature paper you mentioned - spoke globally of brain and other organs (the CNS is very diverse relative to other organs - so treating it with more precision is the norm and will likely yield better results).
So, it really depends on how precise an answer you need and how reliable you want your data to be.
  • asked a question related to Tumor Biology
Question
2 answers
I know the ideal thickness for this staining is usually half of it, but I already have cut my samples on the vibratome and kept them frozen. So now I would like to perform a H&E staining and I would appreciate any suggestion to optimize the staining resolution for that thickness. Or if there is any other staining protocol to localize tumor area on those samples, also might be helpful.
Many thanks in advance,
Claudia
Relevant answer
Answer
Thanks a lot! But my main issue is the thickness of my samples, they are 80 microns thick. I am looking for more information, but thanks for your help anyway!
  • asked a question related to Tumor Biology
Question
4 answers
I am trying to isolate T cells from human glioblastoma for FACS and Sequencing analysis. I tried digestion with collagenase and DNAse and subsequent seperation by 100%75% Ficoll gradient, however the purity is very poor and I would like to improve. Can anyone share experiences or protocols? Thank you!!
Relevant answer
Answer
Katrin-
I have used the MIltenyi pan T cell kit.  It is easy to use, gives great purity (>98%, in my hands).  Miltenyi has streamlined the kit in the past year or so and it is now even easier and quicker to use. 
If you don't have access to a magnet, you could also try differential attachment.  T cells generally don't adhere to tissue culture plastic, but tumor cells, fibroblasts, other stromal cells will.  You can plate the single cell suspension and let the cells settle and adhere for several hours.  Then gently gently gently wash the wells with warm media or PBS and collect the non-adherent cells, the majority of which should be T cells.  The purity will be lower than the magnet, of course, but depending on what you plan to sequence (TCR?) may be good enough.
  • asked a question related to Tumor Biology
Question
9 answers
I have prepared tumour spheroids with U87 MG cells and I am trying to get fluorescence images using confocal microscope. However when I placed tumour spheroids between cover slips and microscope slides, I think they get squeezed and I lose the 3D shape of the spheroids. Do you have any suggestion to prevent this? Thank you.
Relevant answer
Answer
Here is a paper describing a live cell imaging system that was developed by some of my coworkers. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3826880/   Our lab also provides foundry services to customize such devices. http://www.vanderbilt.edu/mfc/
With microfluidic devices, you are able to image your cellular system in a controlled environment that few other platforms are able to achieve. 
  • asked a question related to Tumor Biology
Question
8 answers
I am studying novel immuno therapeutic strategies in cancer and have had trouble in establishing a reliable system to study combination therapy with PD-1 blockade. I am wondering if anyone has had success with such a model. I have tried B16 tumors and EL4 tumors. Thank you.
Relevant answer
Answer
I realise this is an old thread - I'm having trouble getting hold of anti-mouse PD-1 (clone G4 ideally), would any one have access to this (and be willing to ship to Belfast, expenses paid!) or recommend a commercial alternative?
Thanks in advance!
  • asked a question related to Tumor Biology
Question
2 answers
These cell lines along with available xenografts and other factors along with other biomarkers ( if you have any it would be appreciated)  will be used to build a preclinical model for high risk Wilms tumors.  The development of assays specific to this model will result in the ability to do novel cell line and animal testing which could potentially lead to clinical trials with new compounds for children with these disease.
Relevant answer
Answer
sorry no
  • asked a question related to Tumor Biology
Question
1 answer
We have observed high TIM-3 expression on Tregs in a TC-1 tumor and am wondering if they are somehow functional and would TIM-3 blockade have an effect on Tregs' suppressive effects?
Relevant answer
Answer
The short answer is YES. The real question is to what extent? See the relevant info in the link below.
  • asked a question related to Tumor Biology
Question
2 answers
MANY AUTHORS HAVE REPORTED DIFFERENT INCIDENCE AND TUMOR LATENCY FOR RAT MAMMARY TUMORS. CAN WE USE BOTH CARCINOGEN AT DIFFERENT TIME INTERVAL TO INDUCE TUMORS FAST WITH BETTER INCIDENCE?
Relevant answer
Answer
Ok thanks
  • asked a question related to Tumor Biology
Question
4 answers
I have found that cbioportal is a good website to study molecular expression level of certain proteins in certain cancer cell lines. Unfortunately, some cell lines are not in the database. Where can I find information on those cell lines? I am working on esophageal cancer cell lines. I need to get cancer genomic data on kyse50, kyse 110, TE2, TE3. Which websites are suitable for this purpose?
Relevant answer
Answer
Thank you, Fiona!
  • asked a question related to Tumor Biology
Question
7 answers
Hello everyone,
I have some mouse tumors that I am going to harvest. The vet who performs the surgery will place them in an isotonic saline solution, which they will be in for a brief time (< 1 hour) before I can get them back to the lab. I have read many protocols but I still don't know which is best. Right now I see my main assays being H&E, so what I care most about is preserving the morphology and tissue structure. How long could they be left in the saline solution in the fridge at 4 °C? I assume though that they would be better frozen as soon as possible.  I will embed them in tissue freezing medium for cryosectioning. Is it better to store tissues by themselves in -80 °C or first embed them in tissue freezing medium. How important is the freezing rate depending on whether the tissue is embedded in tissue freezing medium or not? The cryomicrotome system that I use has a small area on it that gets down to around -60 °C. If I place the specimen in a plastic mold or a metal mold and freeze it in that small area, is that fast enough? What about just placing it in the -80 °C freezer to freeze? Finally, are snap-freezing protocols or sucrose cryoprotection protocols something I should look into in conjunction with tissue freezing medium embedding? Thank you.
Update (11/12/2015). The undergraduate student who performed the cryosectioning made the mistake of freezing some of the initial samples straight after removal from the saline solution at -80 C. We examined both mouse tumor and mouse spleen. For the pre-frozen samples,  we decided to do fixation followed by cryoprotection in 15% and 30% sucrose on those samples anyways, finally embedding in OCT compound. The spleen had many tears, especially at 10 micron thickness, specifically near the center. A 20 micron thickness gave us the best results, with much less tearing and even some whole slices. The tumors appeared to hold up better despite the initial freezing compared to the spleens. 10 microns did give us more smaller tears running through the tumors, and 20 microns again gave us the best. 
With the fresh samples, they cut great, but it seemed that they started to crack a short time after they were adhered to the slide. Is there anything we can do to avoid this?
Relevant answer
Answer
If your main assay is histological analysis then do not freeze at all but fix in formalin. Frozen sections are rarely as good as sections from formalin fixed tissues when it comes to preservation of tissue morphology.
If you still want to freeze, put tissue first in tissue freezing medium, then freeze. A more detailed discussion on this topic can be found here on Researchgate, foe example:
There is no universal fixation/tissue preservation method. It depends on what your plans are, what you want to study, what downstream applications you plan to do.
Many antibodies for IHC work on formalin-fixed paraffin-embedded tissues (FFPE), many do not. you can get decent protein for Western blotting from FFPE sections but snap-frozen tissue is better. Same is true especially for DNA and RNA.
 Not sure how well DNA and RNA preserve after PFA/formalin fixation and freezing. But if the ratio of tissue to fixative and the size of the tissue are in a certain range, fixation should be fast and nucleic acid degradation at an acceptable level.
  • asked a question related to Tumor Biology
Question
4 answers
Some literature mentions that 4T1 is sensitive to recombinant human TRAIL whereas some articles mention that recombinant human TRAIL cannot affect mice tumors since they don't have death receptors necessary for TRAIL actions.
Relevant answer
Answer
Thank you Mr. Tsyrlov. 
  • asked a question related to Tumor Biology
Question
2 answers
If the relative sphere number with each passage is dropping in a cell that is overexposing a gene associated with increased tumorogenicity, does that mean that a stable overexposing cell line has not been formed?
Relevant answer
Answer
It also can be possible that your overexpression model was not transfected in a stable way.
  • asked a question related to Tumor Biology
Question
3 answers
Hi everyone!
I'm searching for a breast cancer cell line in which Her2 and uPAR are both over-expressed. Does anyone know about any? Thanks in advance
Relevant answer
Answer
Dear Stefania,
Whenever you are searching for expression levels whether basal or differential expression, please give it a try to the EBI Expression Atlas http://www-test.ebi.ac.uk/gxa/  As you can see, when searching for expression of both genes in "mammary gland cell line", it gives you the expression levels of both genes by specific cell line. Please see the attached image with the screenshot containing the cell lines/expression levels and number of experiments. Please let me know if cannot figure out how to get the results and I can send you a brief tutorial
Good luck!
  • asked a question related to Tumor Biology
Question
2 answers
Tumor contains heterogeneous population of cells with different mutations. So, is there any possibility of existence of ‘NRAS mutated-BRAF-WT’ cells in the tumor/cancer lesions of BRAFV600E (Mutant BRAF) positive patients? If so, then how do the NRAS mutated-BRAF-WT cells respond to the inhibitors for BRAF in tumor? What signaling(s) one could expect during combination therapy in such situations? It would be a great help if you could comment, emphasizing some published or unpublished work related to my questions. Thank you.
Relevant answer
Answer
Hi! This is an excellent question, and as you can judge by the two different responses you've obtained so far, this is not an easy question.
As mentioned above, these two mutations are classically considered to be exclusive and not occurring in the same cell. The data presented by Anastasia above, I will leave uncommented as I do not know of such dual-mutated cells in my experience. I do however know that there are clinical tumors where both BRAF-wt/BRAF-mut/NRAS-wt/NRAS-mut cells co-exist in the tumor. As also mentioned in the previous reponses, the BRAF-wt/NRAS-mut cells are not targeted by BRAF inhibitors, such as Vemurafenib. There are some case studies published, one in NEJM if I'm not misstaking, where they found an aquired NRAS mutation in the metastatic daughter tumor, where the primary tumor was "diagnosed" as BRAF-mutant and NRAS-wt and hence treated with BRAF inhibitors. In NRAS-mut/BRAF-wt I would expect an enhanced NRAS-related signalling.
Best of luck!
  • asked a question related to Tumor Biology
Question
5 answers
Our lab uses frequently uses matrigel for intraperitoneal injection of ovarian/endometrial tumour cells. However, there is no literature I can find that describes the use of matrigel with IP injections, and it is only recommended for orthotopic and subcutaneous injections.
Intraperitoneal injection is more like a metastatic model and so it seems as though the formation of a matrigel plug is counter-intuitive.
Should I stick to just using PBS? Or should it not really matter? 
Edit: 
Thank you for all your answers so far! I would like to add that with gynecological cancers, direct spread to the peritoneal cavity is very common; metastasis via the blood stream not so much. That's why we inject tumour cells intraperitoneally.
Relevant answer
Answer
Concerning the use of matrigel with ovarian cancer, i rather suggest to use it for orthotopic or subcutaneous injections, as you already wrote, and not for the intraperitonel ones. Normally, in the abdomen, you expect not to form metastases in a shot time but ascites and the injection whith PBS or media, in my experience, is the best. For methastases is always better iv injection though in ovarian cancer case doesn't really make sense.
Good luck
  • asked a question related to Tumor Biology
Question
5 answers
I did an experiment with 6 mice using 5x105 and 10x6 cells , ( 3 mice each condition), and both cell concentration were rejected in 15 days.
I used matrigel
Cell+matrigel + 50ul
Should I use more cells? How much more?
Relevant answer
Answer
Hi,
Do you have wild type 4T1 cells or transduced with a viral vector? I observed an immune reaction of BalbC mice toward 4T1 cells, which resulted in rejection of primary tumour after approximately 2 weeks. However primary tumour recurred after another ~4 weeks followed by metastatic spread. I implanted 5x10^5 of 4T1 cells trancduced with vector expressing luciferase. It doesn`t happen however when you inject wild type cells. I implanted 1x10^6 and observed continuous growth of primary tumours.  
  • asked a question related to Tumor Biology
Question
6 answers
Does anyone know why these PC12 cells of one picture look a little rough on their surfaces compared to the other one? They look slightly different from usual and I can't figure out why..Humidity issue maybe? I used the same media for both pictures.
Any ideas? Thank you!
Relevant answer
Answer
I have worked with these cells and noticed that using trypsin to remove them from plates for passaging will cause damage after too many uses- I ended up having cells that looked very similar to the ones in the top picture. Therefore, manual scraping for long term/ multiple passaging has worked better for me, with less cell death.
  • asked a question related to Tumor Biology
Question
3 answers
How to measure tumor size in corel pictures. Suppose I have mice pictures with tumors and these tumors are separated from body part. The problem in the quantification of tumor size as by visual and corel measurement not looks correct. Someone have an idea how to quantify these tumors? Thanks in advance.
Relevant answer
Answer
Dear Hem,
Tumour measurements are best done with vernier caliper either in live animals or in excised tumours from sacrificed animals. Quantification is usually done by measuring length and width of the tumour and then using the ellipsoid formula to calculate tumour volume. Quantifying tumour size using pictures can only be reliable if all the pictures are taken using the same photographic parameters like distance of the subject from the camera, magnification etc. Even then, the orientation of the excised tumour could vary, and lead to error in calculations. Hope this helps.
  • asked a question related to Tumor Biology
Question
1 answer
Dear all..
Kindly suggest the alternate for Propylene glycol which is commonly used as a vehicle control in the experiments (Genotoxicity and  antitumor studies) pertaining to EAC models..and also explain why propylene glycol is the most preferred vehicle control for comparison studies done using chemotherapeutic agents.
I have attached an article for better understanding..
Thank you
Relevant answer
Answer
Not really, it depends on your agent and its solubility properties (polarity). This will determine which dissolution vehicle you will use (ethanol,  acetone, DMSO, etc.) It is important to prepare a stock solution so you can keep the concentration of the dissolution vehicle below toxic levels.
  • asked a question related to Tumor Biology
Question
3 answers
When staining both fixed (4.0% PFA in PBS) and permeabilized (1.0% EDTA in PBS) 3D multicellular tumour spheroids (MCTS) with phalloidin for confocal imaging, I get quite unexpected results. Though it may seem that diffusion rate could limit the staining efficiency at the core of the MCTS, but I get reverse results - the core is stained perfectly, but outer rim cells (counterstained with DAPI) seem not to be stained at all (only DAPI appears). Has anyone faced similar problem? Is it probable that PBS washing steps remove phalloidin bound to actin? I would be grateful for any suggestions.
Relevant answer
Answer
What does it look like with only phalloidin staining? Are the out side cells stained then?  In which order do you stain? Or does it happen each way?
  • asked a question related to Tumor Biology
Question
4 answers
I am going to isolate TAMs from some murine models. As I searched, it seems that MACS from miltenyi biotec has been used by a great number of researchers for isolating TAMs but theoretically Easy sep from stem cell has its own advantag