Bulent Karabulut

Ege University, İzmir, Izmir, Turkey

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Publications (53)83.9 Total impact

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    ABSTRACT: The clinical and pathological features of 133 colorectal cancer patients with brain metastasis: a multicenter retrospective analysis of the Gastrointestinal Tumors Working Committee of the Turkish Oncology Group (TOG) Abstract Brain metastasis in colorectal cancer is highly rare. In the present study, we aimed to determine the fre-quency of brain metastasis in colorectal cancer patients and to establish prognostic characteristics of colorectal cancer patients with brain metastasis. In this cross-sectional study, the medical files of colorectal cancer patients with brain metastases who were definitely diagnosed by histopatho-logically were retrospectively reviewed. Brain metastasis was detected in 2.7 % (n = 133) of 4,864 colorectal cancer patients. The majority of cases were male (53 %), older than 65 years (59 %), with rectum cancer (56 %), a poorly differentiated tumor (70 %); had adenocarcinoma histology (97 %), and metachronous metastasis (86 %); received chemotherapy at least once for metastatic disease before brain metastasis developed (72 %), had progression with lung metastasis before (51 %), and 26 % (n = 31) of patients with extracranial disease at time the diagnosis of brain metastasis had both lung and bone metastases. The mean follow-up duration was 51 months (range 5–92), and the mean survival was 25.8 months (95 % CI 20.4–29.3). Overall survival rates were 81 % in the first year, 42.3 % in the third year, and 15.7 % in the fifth year. In multiple variable ana-lysis, the most important independent risk factor for overall survival was determined as the presence of lung metastasis (HR 1.43, 95 % CI 1.27–4.14; P = 0.012). Brain metastasis develops late in the period of colorectal cancer and prognosis in these patients is poor. However, early screening of brain metastases in patients with lung metastasis may improve survival outcomes with new treatment modalities.
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    ABSTRACT: Background: Unlike for fit elderly metastatic colorectal cancer (mCRC) patients, general approaches to initial treatment for the frail older mCRC patients are not clear. Our aim was to evaluate the efficiency and safety of first-line single-agent treatment in one such group. Materials and Methods: We retrospectively evaluated mCRC patients aged 70 or older with an Eastern Cooperative Oncology Group performance score of 2. They had no prior treatment and underwent first-line single-agent capecitabine or other monotherapies until disease progression or unacceptable toxicity. Results: Thirty-six patients were included. Most (n:28, 77.8%) were treated with capecitabine. One patient achieved a complete response and 5 patients had a partial response for an overall response rate of 16.6%. Twelve patients (33.3%) remained stable. Median progression free survival was 5 months (confidence interval (CI), %; 3.59-6.40) and median overall survival was 10 months (95 CI%; 8.1-11.8). Grade 3-4 toxicity was found in 6 patients (16.6%). Febrile neutropenia was not observed and there were no toxicity-associated deaths. Conclusions: Capecitabine is a safe chemotherapeutic agent with moderate activity for first-line treatment of older metastatic colorectal cancer patients with limited performance status.
    Asian Pacific journal of cancer prevention: APJCP 01/2014; 15(7):3157-61. · 1.50 Impact Factor
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    ABSTRACT: Colorectal cancer (CRC) is among the most frequently diagnosed cancers and a major cause of cancer-related mortality worldwide. The aim of the present study was to determine whether there was an improvement in the time to disease progression (TTP) in patients with metastatic colorectal cancer (mCRC) treated with first-line bevacizumab plus chemotherapy, according to tumor characteristics and metastatic sites. Tumor characteristics and tumor burden were considered to be predictive markers of the therapeutic efficacy of bevacizumab. The medical records of 705 patients with mCRC were retrospectively reviewed in three oncology centers between January, 2005 and September, 2012. A total of 101 patients completed their first-line bevacizumab-containing treatment. The median TTP was 6.93 months [interquartile range (IQR)=4.20-9.80 months] in patients treated with irinotecan, 5-fluorouracil (5-FU) and bevacizumab vs. 7.42 months (IQR=6.08-10.68 months) in those treated with oxaliplatin, 5-FU and bevacizumab (P=0.589). When we compared patients with pulmonary metastases (median TTP, 9.9000 months) or other metastatic patients without pulmonary metastasis (median TTP, 6.9000 months), we observed a statistically significant difference (P=0.046). However, when the efficacy of bevacizumab was compared in terms of other tumor characteristics (tumor grade, size and lymph node involvement) and metastatic sites, the differences were not significant (P>0.05). We concluded that bevacizumab may be effective in all subgroups of patients with mCRC. Furthermore, bevacizumab with combination chemotherapy may be superior to combination chemotherapy only as the first-line treatment of patients with mCRC and pulmonary metastasis.
    Molecular and clinical oncology. 01/2014; 2(1):166-170.
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    ABSTRACT: PurposeWe aimed to investigate the improvement in symptoms, quality of life, patient and family satisfaction with care, and direct costs resulting from a palliative care program based case management model.Methods The research was implemented at the Medical Oncology Clinic hospital of a University between September 2009 and September 2011. The research sample consisted of a total of 44 patients (22 control and 22 intervention group). The research tools were the Edmonton Symptom Diagnosis System, the Karnofsky Performance Scale, the EORTCQLQ-C30 Quality of Life Scale, a patient and family satisfaction form, and a patient cost record form.ResultsThe difference between total symptom mean scores and the sub-dimension symptoms of pain, fatigue, nausea, depression, anxiety, lack of appetite, lethargy, well-being, dyspnea, and constipation post-hospitalization and post-discharge of patients in the control and experimental groups were found to be statistically significant (p < 0.05). The level of decrease in symptom severity in the experimental group patients was more than in the control group (p < 0.000). The satisfaction level of patients and family in the palliative care based case management service was higher than that for conventional service in the control group (p < 0.05). No statistical difference was detected between the experimental and control groups regarding health costs and duration of hospitalization (p > 0.05).Conclusion We provided a better symptom control, improved the patient s quality of life (excluding physical and congnitive functions), and patient and family satisfaction levels were higher in the palliative care based case management intervention group, but direct health costs were not affected.
    The American journal of hospice & palliative care 10/2013;
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    The European Cancer Congress, Amsterdam, Holland.; 10/2013
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    ABSTRACT: INTRODUCTION: The purpose of our study was to evaluate the perioperative complications, toxicity, mortality rates after cytoreductive surgery (CRS), and effects of hyperthermic intraperitoneal chemotherapy (HIPEC) used in the treatment of peritoneal surface malignancies. METHODS: Between September 2007 and March 2012, we performed 118 CRS and HIPEC with the closed abdominal technique on 115 patients with peritoneal carcinomatosis (PC). Systemic toxicities were graded according to the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 3.0 criteria and were analyzed from a prospectively collected database. RESULTS: The mean age of patients was 53.4 (range, 20-82) years; 76.3 % were female. PC was synchronous to primary cancer in 53.4 % of patients, metachronous in 41.5 %, and recurrent in 5.1 % of the patients. PCI was ≥15 in 53.4 % of the patients, and CC-0 cytoreduction was achieved in 68.5 % of the patients. Perioperative mortality was observed in 9 (7.6 %) patients. A total of 98 complications were observed in 46 (39.0 %) patients, and 4 patients underwent 6 reoperations for perioperative surgical complications. We observed toxicity in 25.4 % of the patients, nephrotoxicity in 18.6 %, and hematological toxicity in 13.6 % of patients. No significant difference was observed among age, gender, PCI and CC scores, origin of the primary tumor, and occurrence of toxicity and surgical complications. Prolonged operation times resulted in higher complication and/or toxicity rates (P < 0.01). CONCLUSIONS: Cytoreductive surgery and HIPEC is a combined treatment strategy for peritoneal surface malignancies with acceptable complication and toxicity rates.
    Annals of Surgical Oncology 03/2013; · 4.12 Impact Factor
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    ABSTRACT: What's known on the subject? and What does the study add? Prostate cancer is the second most common cancer diagnosed among elderly men. Current standard of care with surgery, chemotherapy or radiation in prostate cancer patients are of limited efficacy, especially in the androgen refractory state of the disease, and unfortunately metastatic disease remains incurable. Skeletal metastases are the most common site for metastases for prostate cancer and bisphosphonates have been widely used for the treatment of morbidity due to skeletal related events. Zoledronic acid (ZA) is the most potent member of the nitrogen containing new generation bisphosphonate (N-BPs) family. Okadaic acid (OA) and Calyculin A (CA) are the most commonly used inhibitors of PP1 and 2A. OA, extracted from common black sponge Halachondria okaddai is a potent inhibitor of protein phosphatases, PP1 and PP2A, and CA was isolated from another marine sponge, Discodermia calyx. Therapies based on combinations of chemotherapeutics with phosphatase inhibitors that target signaling pathways within the cell with different mechanisms of action, may be useful for increasing therapeutic effect and also diminish toxic side effects by decreasing the doses of conventional chemotherapeutics. Although clinically well known, the in vitro effects of ZA on cancer cells and the underlying mechanisms are not well elucidated. In our previous studies, we have already shown anticancer effect of ZA in hormone-and drug refractory prostate cancer cells, PC-3 and DU-145. In addition to this, we have also shown that this anticancer effect may be augmented with some cytotoxic agents in prostate cancer. Now, in our present study, we have investigated whether ZA induced growth inhibition and apoptosis in PC-3 and DU-145 may be enhanced by the combination with CA or OA, through inhibition of serine/threonine phosphatases in prostate cancer cells. Both ZA/CA and ZA/OA combinations inhibited the cell viability of hormone-and drug refractory prostate cancer cells at in vivo achievable therapeutic concentrations. Moreover, a potentiation of the apoptotic effects of the combinations was also observed in the same experimental conditions. This is the first report of a synergistic combination of ZA with phosphatase inhibitors CA and OA which inhibits cell viability and induces apoptosis in human hormone and drug refractory prostate cancer cells. OBJECTIVES: •  To investigate if the cytotoxic and apoptotic effect of zoledronic acid (ZA) can be enhanced by the addition of the serine/threonine protein phosphatase inhibitors calyculin A (CA) and okadaic acid (OA) in hormone and drug refractory prostate cancer cells, PC-3 and DU-145. •  To discover the effect of these combination treatments on phosphatase 1 (PP1) and PP2A protein expression levels in prostate cancer cells. MATERIALS AND METHODS: •  An XTT cell viability assay was used to determine cytotoxicity. •  Apoptosis was evaluated by enzyme-linked immunosorbent assay (ELISA) using a Cell Death Detection ELISA Plus Kit and verified by measuring caspase 3/7 enzyme activity. •  The PP1 and PP2A enzyme activities were evaluated by serine/threonine phosphatase ELISA and expression levels of PP1 and PP2A proteins were then re-assessed by Western blot analysis. RESULTS: •  Combination of ZA with either CA or OA showed synergistic cytotoxicity and apoptosis compared with any agent alone in both PC-3 and DU-145 prostate cancer cells. •  The combination of ZA with phosphatase inhibitors resulted in enhanced suppression of both PP1 and PP2A enzyme activity and protein levels, which was more overt with the ZA/CA combination. CONCLUSION: •  Results from our study increase the translational potential of our in vitro findings and offer the basic rationale for the design of new combinatory strategies with ZA and phosphatase inhibitors for the treatment of prostate cancer, which may become resistant to conventional therapy.
    BJU International 08/2012; · 3.05 Impact Factor
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    ABSTRACT: OBJECTIVES:: The liver is the most common metastatic site in colorectal cancer (CRC). In this study, we evaluated if there is any difference between first-line irinotecan-based and oxaliplatin-based chemotherapies in the duration of time to disease progression (TTP) in CRC patients with only liver metastasis. METHODS:: We retrospectively reviewed the medical records of patients with metastatic CRC referred to the Medical Oncology Department at the Faculty of Medicine of Ege University, between January 2002 and December 2010. Seventy-seven patients had only liver metastasis and completed their first-line chemotherapy. Forty-two patients had oxaliplatin-based treatments while 12 also had bevacizumab therapy, and 35 patients had irinotecan-based treatments while 16 also had bevacizumab therapy. RESULTS:: Median TTP was 6.70±0.29 months for patients treated with oxaliplatin+5-fluorouracil (5-FU) and 8.33±1.15 months for patients treated with oxaliplatin+5-FU+bevacizumab. TTP was significantly improved for patients who received irinotecan+5-FU+bevacizumab (median TTP, 13.73±2.10 mo) when compared with irinotecan+5-FU (median TTP, 5.13±0.70 mo). CONCLUSIONS:: Although previous studies showed no survival difference between these 2 chemotherapeutic agents in metastatic CRC, there might be differences in the benefit of delaying the disease progression in subgroup populations. Irinotecan+5-FU with bevacizumab combination chemotherapy may be superior in the first-line treatment of CRC with hepatic only metastasis.
    American journal of clinical oncology 05/2012; · 2.21 Impact Factor
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    ABSTRACT: To investigate the frequency and significance of pulmonary nodules in patients with colorectal cancer (CRC). Medical records of 1,344 patients with CRC who underwent thoracic computerized tomography scans between January 2003 and December 2009 were reviewed. Those with any distant metastatic disease or who were already known to have pulmonary malignancies were excluded. Number, size, shape and location of the nodules were evaluated. A multivariate analysis was performed to determine the predictive factors for evidence of metastases. Of the 1,344 patients, 55 (4.09%) had nodules that met the criteria of an indeterminate pulmonary nodule. The mean follow-up time was 25 ± 17.9 months and the mean time to develop pulmonary metastasis was 15.5 ± 6.4 months. The nodules of 17 (30.9%) patients showed progression at follow-up; 8 had metastasized. Multivariate analysis showed multiple indeterminate pulmonary nodules (p = 0.006) of parenchymal localization (p = 0.016) with an irregular border (p = 0.002), which is predictive of metastatic disease. Our study has shown that multiple indeterminate pulmonary nodules with an irregular border in a parenchymal location were more likely to represent metastatic disease. However, the frequency of the occurrence of indeterminate pulmonary metastases of CRC was low.
    Medical Principles and Practice 04/2012; 21(5):457-61. · 0.96 Impact Factor
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    ABSTRACT: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily and has been shown to induce extrinsic pathway of apoptosis in many types of cancer cells. AT-101, an (-)-enantiomer of gossypol, is a potent anticancer agent that is shown to be an inhibitor of Bcl-2/Bcl-XL. In this study, we searched whether pretreatment with either of these drugs would result in the enhancement of apoptosis through induction of death receptors and activation of mitochondrial pathways within breast cancer cells. Human breast cancer (MCF-7 and MDA-MB-231) and normal breast cells (MCF-10A) were treated with drugs alone/in combination/sequentially. XTT cell viability assay was used to evaluate cytotoxicity. For showing apoptosis, both DNA Fragmentation and caspase 3/7 activity measurements were done. ELISA and Western blot analysis were done to assess DR4 and DR5 protein levels. The expression levels of apoptotic proteins were assessed by human apoptosis antibody array. The sequential treatment of AT-101 followed by TRAIL resulted in significant synergistic cytotoxicity and apoptosis. Moreover, pretreatment of breast cancer cells with AT-101 and then with TRAIL caused enhancement of the expression levels of DR4 and DR5 in both cancer cell lines, suggesting that these cells were under strong apoptotic stimuli. These findings all together, strongly suggest that pretreatment with AT-101 enhances TRAIL-induced death-inducing signaling complex resulting in the engagement of the mitochondrial pathway to apoptosis in breast cancer cells. These promising, preliminary results make AT-101 and TRAIL a novel combination treatment candidate for breast cancer.
    Journal of Cancer Research and Clinical Oncology 03/2012; 138(7):1155-63. · 2.91 Impact Factor
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    ABSTRACT: The aim of this study was to determine the markers of prognosis in metastatic inflammatory breast cancer (IBC). The prognostic value of patients' clinical characteristics and expression of c-erbB-2, p53, Ki-67, ER and PgR were assessed in the 45 patients with IBC who had developed distant metastasis. Immunohistochemical methods were used to detect the expression of c-erbB-2, p53, Ki-67, ER and PgR in surgical resection specimens of the patients' primary tumor. The median overall survival (OS) measured from the diagnosis of metastatic disease was 23 months. In the univariate analysis, p53 protein accumulation and the presence of visceral metastasis were predictive of poor survival (p = 0.01 and 0.003, respectively). In the multivariate analysis, accumulation of p53 protein and the presence of visceral metastasis correlated with OS (p = 0.02 and 0.008, respectively). In metastatic IBC, accumulation of p53 protein and presence of visceral metastasis are independent prognostic factors for OS. Established prognostic factors in non-IBC patients such as patient age, histologic grade, hormone receptor status and c-erbB-2 status did not have independent significance in IBC in this study.
    Medical Principles and Practice 01/2011; 20(2):159-64. · 0.96 Impact Factor
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    ABSTRACT: This study compared the two different commercially available in vitro viability assays: XTT and Alamar blue (AB), to detect anti-proliferative effects of AT-101, a cotton plant extract, on six different human carcinoma cell lines including: prostate (PC-3 and DU-145), breast (MCF-7 and MDA-MB-231), and ovary (OVCAR-3 and MDAH 2774) in a time- and dose-dependent manner. Cells were exposed to AT-101 in the concentration range of 2.5-40 µM for 24, 48, and 72 h. The AB assay was slightly more sensitive than the XTT assay in the evaluation of AT-101 at 24 h, suggesting that the AB assay might be used for detecting early changes in cell viability as compared to the XTT assay. Moreover, the AB assay showed less intra-assay variability as compared to the XTT. The non-toxic, non-radioactive AB metabolism assay allows rapid assessment of large numbers of samples, with simple equipment and at reduced cost for continuous monitoring of cancer cell viability, and, thus, should be accepted as a suitable alternative viability method.
    Toxicology mechanisms and methods 10/2010; 20(8):482-6. · 1.37 Impact Factor
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    ABSTRACT: We report that all-trans retinoic acid (ATRA) in combination with zoledronic acid has strong synergistic cytotoxic and apoptotic effects against human hormone- and drug-refractory prostate cancer cells, PC-3 and DU-145, in a time- and dose-dependent manner. We further investigated the effect of the combination treatment on the apoptotic process by both oligoarray and protein array analysis in DU-145 cells, in which the drug combination shows much more strong synergistic effects, as compared to PC-3 cells. Moreover, we have also performed real time-PCR array analysis to validate oligoarray results. We demonstrated that the combination of ATRA and zoledronic acid is a strong inducer of apoptotic related cell death in human androgen-and drug refractory prostate cancer cells DU-145, at either transcriptional or translational levels. While expression of proapoptotic genes such as tumor necrosis factor receptor superfamily (TNFRSF), Bad, Bax, Fas, FADD are induced with the exposure of the combination, expression of antiapoptotic genes or proteins such as members of inhibitor apoptosis family (IAPs), MCL-1, LTBR, p53 and bcl-2 are reduced. Because this novel combination treatment has fewer side effects than is generally the case with conventional cytotoxic agents, this regimen may be a good option for treatment of elderly prostate cancer patients.
    Molecular Biology Reports 03/2010; 38(1):249-59. · 2.51 Impact Factor
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    ABSTRACT: Over 80% of patients with advanced breast and prostate cancer ultimately develop bone metastases. Ibandronic acid has proven efficacy for treatment of bone metastasis secondary to breast cancer. This study was designed to investigate the cytotoxic and apoptotic effects of ibandronic acid on hormone- and drug-refractory prostate carcinoma DU-145 and human breast cancer MCF-7 cell lines. Cytotoxicity was evaluated using an XTT cell proliferation kit, and apoptosis was assessed by enzyme-linked immunosorbent assay (histone-DNA fragmentation) and measurement of caspase 3/7 activity. With increasing concentrations of ibandronic acid there was a dose- and time-dependent decrease in cell numbers. MCF-7 cells were more resistant than DU-145 cells (half maximal inhibitory concentrations of 122 and 90 microM, respectively). Ibandronic acid induced apoptosis in both cell lines. The study showed an apoptosis-mediated cytotoxic effect for ibandronic acid (in addition to the already known osteoclast inhibiting effect) in breast cancer patients with bone metastases; which was also observed in prostate cancer cells. Further clinical studies involving breast and prostate cancer patients with bone metastases are warranted to confirm these findings.
    The Journal of international medical research 01/2010; 38(5):1663-72. · 0.96 Impact Factor
  • Journal of palliative care 01/2010; 26(4):305-10. · 0.71 Impact Factor
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    ABSTRACT: many drugs have been tested to increase the sensitivity of prostate cancer cells to radiotherapy. Gossypol, a natural polyphenolic compound extracted from the cotton plant, is one of the agents the efficacy of which has been investigated in the treatment of prostate cancer for this purpose. The main aim of this study was to investigate the best gossypol application with irradiation, when gossypol was applied either sequentially (24 h before and after irradiation) or concurrently in PC-3 hormone-refractory and radioresistant prostate cancer cells. The XTT viability assay was used to evaluate the cytotoxicity of different concentrations of gossypol in PC- 3 cells. Irradiation was applied to PC-3 cells via 6 MV photon linear accelerator and delivered 24 h before, 24 h after radiation or at the same time with gossypol administration. gossypol caused radiosensitization of PC-3 cells that are known to be radioresistant, with high Bcl-2 levels. Among different applications of gossypol and irradiation (before, after and concurrent) in prostate cancer cells, the best results were observed by the application of gossypol 24 h before irradiation. our study suggests that gossypol represents a promising novel anticancer treatment for radiosensitization of human hormone-refractory prostate cancer cells.
    Journal of B.U.ON.: official journal of the Balkan Union of Oncology 01/2010; 15(4):763-7. · 0.76 Impact Factor
  • Clinical Nutrition Supplements 01/2010; 5(2):136-137.
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    ABSTRACT: Ovarian cancer is the most fatal gynecologic malignancies in the world. Although, platinum based treatments are widely used, the disease becomes treatment refractory within two years, and novel treatment options should be searched. All- trans retinoic acid (ATRA) induces growth arrest, differentiation and cell death in some types of cancer cells and its combination with various anticancer agents results in enhanced cytotoxicity. Zoledronic acid is a common bisphosphonate known for its anticancer effects beyond its current use in the treatment of cancer-induced bone disease. We aimed to investigate the possible additive/synergistic effect of both agents in OVCAR-3 and MDAH-2774 ovarian cancer cell lines, since both agents show superiority to conventional cytotoxics in terms of adverse events. XTT cell proliferation assay was used for showing cytotoxicity. For verifying apoptosis, both DNA Fragmentation by ELISA assay and caspase 3/7 activity measurement were used. OligoGeArray which consists of 112 apoptosis related genes was used to elucidate the genetic changes within cancer cells. To validate our oligoarray results, quantitative real-time PCR was performed on four selected genes that were maximally effected by the combination treatment: lymphotoxin beta receptor (LTBR), myeloid cell leukemia-1 (MCL-1), tumor necrosis factor receptor superfamily, member 1A (TNFRSF1A), TNFRSF1A-associated death domain protein (TRADD). We demonstrated that a novel combination of ATRA and zoledronic acid is a strong inducer of apoptotic related cell death in both ovarian cancer cells. While the combination therapy significantly induced proapoptotic genes such as tumor necrosis factor receptor superfamily (TNFRSF), TRADD and caspase 4, some of the antiapoptotic genes such as members of MCL-1, LTBR, BAG3 and Bcl-2 family members were inhibited. These are the preliminary molecular results of a novel combination treatment of ATRA and zoledronic acid, with fewer side effects as compared to conventional cytotoxic agents. With additional experimental analysis, it may serve as a good option for the treatment of refractory and elderly ovarian cancer patients, for whom there exists very limited choice of treatment.
    Journal of Experimental & Clinical Cancer Research 01/2010; 29:102. · 3.07 Impact Factor
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    ABSTRACT: To compare the effect of racemic gossypol with its (-)/(-) enantiomer (AT-101) on expression profiles of angiogenic molecules by mRNA levels in human ovarian cancer cell line OVCAR-3. Cell viability assay (2,3-bis (2-methoxy-4-nitro-5- sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide) was used to detect cytotoxicity of gossypol enantiomers. DNA fragmentation by an enzyme-linked immunosorbent (ELISA) assay was used to evaluate the rate of apoptosis. The mRNA expression levels of angiogenic molecules were investigated by Human Angiogenesis RT2 ProfilerTM PCR Array (SuperArray, Frederick, MD). Both racemic form and AT-101 resulted in a significant cytotoxicity and induced apoptosis. This effect was observed in a dose- and time dependent manner. However, AT-101 was much more potent. In addition, the treatment of 10 microM of racemic gossypol alone and 3 microM of AT-101 alone resulted in significant down-regulation (>or= 3 fold) in mRNA levels of some pivotal angiogenic molecules in OVCAR-3, but altered gene profiles were different by the treatment of each enantiomer. The efficacy of two gossypol enantiomers in OVCAR-3 cells showed distinction. AT-101 was much more potent than racemic gossypol, not only by means of cell death and apoptosis, but also by modulation of angiogenic molecules released from OVCAR-3 cells. Further studies with endothelial cells should be done to verify the anti-angiogenic effect of gossypol enantiomers in cancer treatment.
    Experimental oncology 12/2009; 31(4):220-5.
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    ABSTRACT: In the present study, we aimed to evaluate the possible synergistic, cytotoxic effects of combination treatment of gossypol and zoledronic acid, in human ovarian cancer cell lines, OVCAR-3 and MDAH-2774, and to elucidate the role of this novel combination treatment on angiogenesis-related molecules in ovarian cancer. The XTT cell viability assay was used for showing cytotoxicity. Both DNA fragmentation by ELISA assay and caspase 3/7 activity measurement were used for demonstrating apoptosis. To elucidate the angiogenic molecules affected by combination treatment, mRNA levels of angiogenic molecules were measured using the Human Angiogenesis RT2 ProfilerTM PCR Array (SuperArray, Frederick, MD) in ovarian cancer cell lines, OVCAR-3 and MDAH-2774.The combined treatment resulted in significant, synergistic cytotoxicity, and induced apoptosis. This effect was observed to happen in a dose- and time-dependent manner. Moreover, the combination treatment of 10 microM gossypol and 5 microM zoledronic acid resulted in significant down-regulation (>or= thee-fold) in mRNA levels of some pivotal angiogenic molecules in OVCAR-3 and MDAH-2774 cells as compared to the untreated control. However, this effect was different in the two ovarian cancer cell lines observed. Gossypol, in combination with zoledronic acid, may provide a rational treatment option for ovarian cancer, not only by direct inhibition of cell proliferation, but also inhibition of angiogenesis-related molecules.
    European cytokine network. 09/2009; 20(3):121-30.

Publication Stats

258 Citations
83.90 Total Impact Points

Institutions

  • 2001–2013
    • Ege University
      • • Department of Medical Biology
      • • Faculty of Medicine
      • • Department of Internal Medicine
      İzmir, Izmir, Turkey
  • 2009–2010
    • Celal Bayar Üniversitesi
      • Department of Biology
      Manisa, Manisa, Turkey