Preclinical evaluation of olaparib and metformin combination in BRCA1 wildtype ovarian cancer.

OBJECTIVES: BRCA mutated ovarian cancers show increased responsiveness to PARP inhibitors. PARP inhibitors target DNA repair and provide a second hit to BRCA mutated tumors, resulting in "synthetic lethality". We investigated a combination of metformin and olaparib to provide "synthetic lethality" in BRCA intact ovarian cancer cells. METHODS: Ovarian cancer cell lines (UWB1.289, UWB1.289.BRCA, SKOV3, OVCAR5, A2780 and C200) were treated with a combination of metformin and olaparib. Cell viability was assessed by MTT and colony formation assays. Flow cytometry was used to detect cell cycle events. In vivo studies were performed in SKOV3 or A2780 xenografts in nude mice. Animals were treated with single agent, metformin or olaparib or combination. Molecular downstream effects were examined by immunohistochemistry. RESULTS: Compared to single drug treatment, combination of olaparib and metformin resulted in significant reduction of cell proliferation and colony formation (p<0.001) in ovarian cancer cells. This treatment was associated with a significant S-phase cell cycle arrest (p<0.05). Combination of olaparib and metformin significantly inhibited SKOV3 and A2780 ovarian tumor xenografts which were accompanied with decreased Ki-index (p<0.001). Metformin did not affect DNA damage signaling, while olaparib induced adenosine monophosphate activated kinase activation; that was further potentiated with metformin combination in vivo. CONCLUSION: Combining PARP inhibitors with metformin enhances its anti-proliferative activity in BRCA mutant ovarian cancer cells. Furthermore, the combination showed significant activity in BRCA intact cancer cells in vitro and in vivo. This is a promising treatment regimen for women with epithelial ovarian cancer irrespective of BRCA status.

Prognostic impact of lymphadenectomy in uterine serous cancer.

OBJECTIVE: To estimate the survival impact of lymphadenectomy in women diagnosed with uterine serous cancer. DESIGN: Women with a diagnosis of uterine serous cancer were identified from the Surveillance, Epidemiology and End Results Program (SEER) from 1988 to 2007. Only surgically treated women were included. SETTING: The Surveillance, Epidemiology and End Results Program database provided data from 17 registries. POPULATION: The study population comprised 4178 women. METHODS: Statistical analyses using Student's t-test, Kaplan-Meier survival methods and Cox proportional hazards regression were performed. MAIN OUTCOME MEASURE: Overall survival. RESULTS: Three thousand, one hundred and ninety-four (67.7%) women underwent lymphadenectomy. Older women (≥65 years) and Caucasian women (relative to Asian) were less likely to have lymphadenectomy (P < 0.001). The prevalence of nodal metastasis in women having lymphadenectomy was 32%. Of the 1997 women who had disease grossly confined to the uterus and underwent lymphadenectomy, 387 (19%) were found to have nodal metastasis. Lymphadenectomy was associated with improved survival; women who underwent lymphadenectomy were 41% (hazard ratio [HR], 0.59; 95% confidence interval [CI], 0.54-0.64; P < 0.001) less likely to die than women who did not have the procedure. Moreover, more extensive lymphadenectomy correlated positively with survival. Compared with women with 1-10 nodes removed, those with more extensive lymphadenectomy (>10 nodes removed) were 26% (HR, 0.74; 95% CI, 0.67-0.83; P < 0.001) less likely to die. The impact of the extent of lymphadenectomy on survival was significant in both node-negative and node-positive women. CONCLUSION: Age and race influenced the prevalence of lymphadenectomy in our cohort. This study suggests that the extent of lymphadenectomy is associated with significant improvement in survival of women with uterine serous cancer.

Prognostic impact of lymphadenectomy in clinically early stage malignant germ cell tumour of the ovary.

BACKGROUND: The aim of this study was to determine the impact of lymphadenectomy and nodal metastasis on survival in clinical stage I malignant ovarian germ cell tumour (OGCT). METHODS: Data were obtained from the National Cancer Institute registry from 1988 to 2006. Analyses were performed using Student's t-test, Kaplan-Meier and Cox proportional hazard methods. RESULTS: In all, 1083 patients with OGCT who have undergone surgical treatment and deemed at time of the surgery to have disease clinically confined to the ovary were included 590 (54.48%) had no lymphadenectomy (LND-1) and 493 (45.52%) had lymphadenectomy. Of the 493 patients who had lymphadenectomy, 441 (89.5%) were FIGO surgical stage I (LND+1) and 52 (10.5%) were upstaged to FIGO stage IIIC due to nodal metastasis (LND+3C). The 5-year survival was 96.9% for LND-1, 97.7% for LND+1 and 93.4% for LND+3C (P=0.5). On multivariate analysis, lymphadenectomy was not an independent predictor of survival when controlling for age, histology and race (HR: 1.26, 95% CI: 0.62-2.58, P=0.5). Moreover, the presence of lymph node metastasis had no significant effect on survival (HR: 2.7, 95% CI: 0.67-10.96, P=0.16). CONCLUSION: Neither lymphadenectomy nor lymph node metastasis was an independent predictor of survival in patients with OGCT confined to the ovary. This probably reflects the highly chemosensitive nature of these tumours.

Effects of prostaglandin E(2) on proliferation and apoptosis of epithelial ovarian cancer cells.

OBJECTIVE: There is strong evidence indicating that prostaglandins (PG) and their synthesizing enzyme cyclooxygenase-2 (COX-2) play an important role in tumorigenesis. The purposes of the present study were to determine the pattern of expression of COX-2 and the effect of PG treatment on proliferation and apoptosis in epithelial ovarian cancer cells. METHODS: Two epithelial ovarian cancer cell lines, MDAH-2774 and SKOV3, were grown in flasks to confluence. Cells were then treated with exogenous dimethyl prostaglandin E(2) (dmPGE(2)) at increasing concentrations of 0-10 microg/mL. Total RNA was extracted from cells at different treatment doses and subjected to reverse transcriptase-polymerase chain reaction for the semiquantitative analysis of COX-2, Bcl-2, and bax expression. Flow cytometry was performed to assess effect of treatment on the cell cycle. The TUNEL assay was used to assess apoptosis. RESULTS: We found that COX-2 was constitutively expressed in the MDAH-2774 and SKOV3 epithelial ovarian cancer cells as determined by detection of a 304-bp amplified fragment using specific primers for the COX-2 gene. Treatment of both cell lines with dmPGE(2) resulted in dose-dependently higher expression of COX-2, Bcl-2, and bax mRNA compared with untreated cells. These changes were associated with an increase in the proliferative fraction and with a simultaneous reduction in apoptosis. CONCLUSIONS: Prostaglandin E(2) stimulated proliferation and reduced apoptosis in epithelial ovarian cancer cells. These effects were associated with overexpression of COX-2 and an increase in the ratio of Bcl-2:bax mRNA.

Maspin expression and localization impact on angiogenesis and prognosis in ovarian cancer.

INTRODUCTION: The goal of this study is to evaluate the relation of maspin expression and its cellular localization to markers of angiogenesis in epithelial ovarian serous carcinoma (OSC). MATERIALS AND METHODS: We identified 118 patients with high-grade advanced stage OSC who were treated at our institution. Clinical data were collected, and immunohistochemistry (IHC) with antibodies to VEGF, CD34, COX-2, and maspin was performed on paraffin-embedded tumor blocks. CD34 immunostaining was used to determine microvessel density. The correlation between the various molecular markers was assessed using the Chi-square test. Survival analysis was computed using the Kaplan-Meier model, and various prognostic variables were compared using Cox regression analysis. RESULTS: Maspin expression was noted in 81.4% (96/118) of tumors. Expression was localized to the nuclear compartment in 21.2% of cases, whereas 60.2% of cases showed evidence of cytoplasmic +/- nuclear expression. Tumors that exhibited nuclear maspin expression had lower VEGF and COX-2 expression than tumors with negative or cytoplasmic expression. Tumors with high nuclear maspin expression had lower mean MVD than those with low or negative expression. The median survival based on localization of maspin was 1146 days for those with negative tumors, 1803 days for those with nuclear maspin, and 637 days for those with cytoplasmic maspin (P < 0.001). In a Cox regression analysis, maspin localization was an independent prognostic factor. CONCLUSION: Maspin expression and localization seem to play a role in ovarian cancer angiogenesis and progression. High nuclear expression was associated with reduced markers of angiogenesis and prolonged survival.

The racial disparity in outcomes in endometrial cancer: could this be explained on a molecular level?

OBJECTIVE: The racial disparities among patients with endometrial carcinoma have been previously reported. The objective of this study is to analyze and compare the molecular profiles in endometrial cancer in Caucasian and African American patients using a number of known molecular markers. MATERIALS AND METHODS: 147 patients diagnosed with endometrial cancer between 1995 and 2001 were included in the study. Patients' demographics, clinical and pathological data were reviewed. Immunohistochemical staining for p53, VEGF, Ki-67 and HIF-1alpha was performed on tissue micro array sections. Tumors' expression of p53, VEGF, Ki-67, and HIF-1alpha was compared based on ethnicity and tumor type (Type I = endometrioid carcinomas and Type II = non-endometrioid carcinomas). Spearman's correlation and Fisher's Exact Tests were used for statistical analysis and Kaplan-Meier, log-rank and Cox regression were used for survival analysis. RESULTS: 97 patients were Caucasian and 50 patients were African American. The mean age was 62 (33-91) years for Caucasian patients and 63.5 (24-89) years for the African American patients. African American patients had more Type II carcinoma than Caucasian patients (P = 0.055). High p53 expression was statistically significant among the African American patients (49% vs. 30%, P = 0.035) versus Caucasian patients. There was no significant difference demonstrated when comparing the VEGF, Ki-67, and HIF-1alpha expression between the racial groups. Survival analysis showed a trend toward a shorter survival in the African American patients compared to the Caucasian patients; median survival 62 versus 77 months (P = 0.061). On the other hand, we did not find a significant difference in survival by ethnicity when we adjusted for tumor histology. CONCLUSION: While African American patients with endometrial cancer seem to show a trend toward a shorter survival, this seems to be mainly due to the fact that they have a higher proportion of Type II tumors. The molecular profiles for p53, Ki-67, VEGF and HIF-1alpha expression of histologically matched tumors were similar between the two ethnic groups.

Critical evaluation of secondary cytoreduction in recurrent ovarian cancer.

OBJECTIVE: The optimal strategy for salvage therapy in patients who suffer from ovarian cancer recurrence after a disease-free interval is not established. The objective of this paper is to analyze the existing published data on salvage surgery in this setting. METHODS: A retrospective review of the English literature was done looking at studies addressing the role of secondary cytoreductive surgery in recurrent ovarian cancer. A number of parameters were collected from these studies and analyzed, including patients' characteristics, outcome of secondary cytoreduction, perioperative complications, postoperative therapy, and survival. In a parallel analysis, we reviewed the outcome of patients treated with salvage chemotherapy without surgery in similar clinical settings. RESULTS: Optimal cytoreduction was achievable in 38-87% of the study populations reviewed with acceptable perioperative complications and mortality. The attempt to analyze the impact of secondary cytoreduction on survival was limited by (1) the inter-investigator differences in defining optimal cytoreduction, (2) the heterogeneity of the patients included, (3) and the lack of information on postoperative therapy. All the studies suggest that patients left with no gross residual disease after secondary cytoreduction seem to benefit from prolonged survival in the range of 44-60 months. Current data reveal that the use of combination chemotherapy without surgery for salvage treatment of recurrent ovarian cancer can be associated with prolonged median survival reaching up to 35 months. CONCLUSION: The available data suggest a benefit for secondary surgical cytoreduction in recurrent ovarian cancer. This needs to be considered in the light of recent data reporting prolonged survival with the use of combination salvage chemotherapy without surgery. Currently, it is not known if a salvage strategy combining surgery and multiagent chemotherapy regimens will have a survival benefit over chemotherapy alone. Hopefully, current ongoing prospective trials will answer this question.

Conservative surgery in a young patient with peritoneal psammocarcinoma.

Psammocarcinoma is a rare epithelial neoplasm of the ovary and peritoneum. The reported management of patients with this tumor includes radical surgery and chemotherapy. We report the case of a young woman with metastatic psammocarcinoma treated with conservative surgery who is alive 6.5 years following positive second-look laparotomy.

Utility of lymphangiography in the prediction of lymph node metastases in patients with cervical cancer.

Our objective was to assess the value of lymphangiography in selecting patients for surgical staging of locally advanced cervical cancer. We reviewed our computerized database to identify patients with cervical cancer who had abnormal findings on lymphangiography and underwent retroperitoneal lymph node dissection between September 1991 and January 1996. The records of these patients were retrospectively reviewed, and the following data were retrieved: clinical tumor stage and findings on lymphangiography at surgery, and on pathologic examination of resected lymph nodes. The lymphangiograms were reviewed and reinterpreted in blinded fashion by two of the authors. The positive and negative predictive values of lymphangiography for the presence of lymph node metastases were calculated, with findings on pathologic examination of lymph nodes used as the gold standard. The positive and negative predictive values of surgeons' clinical assessments at surgery were also calculated. Fifty patients met the selection criteria and constituted the study population. Fourteen patients (28%) had histologically negative nodes, and 36 patients (72%) had lymph node metastases. Thirty-three patients had metastases to pelvic nodes, 1515 patients had metastases to common iliac nodes, and 1616 patients had metastases to para-aortic nodes. The positive predictive value of lymphangiography for lymph node metastases was 74% for pelvic nodes, 73% for common iliac nodes, and 88% for para-aortic nodes. The negative predictive value of lymphangiography for lymph node metastasis was 76% for common iliac nodes and 77% for para-aortic nodes. Overall, 46% of the patients selected for surgical exploration had histologic findings of either common iliac or para-aortic lymph node metastases; these findings led clinicians to extend radiation fields to cover the para-aortic lymph nodes. Lymphangiography is helpful in selecting patients with cervical cancer who have a high risk of common iliac or para-aortic lymph node metastasis. However, more accurate and more readily available noninvasive methods of evaluating cervical patients for the presence of regional disease continue to be needed.

Inhibition of paclitaxel-induced apoptosis by the specific COX-2 inhibitor, NS398, in epithelial ovarian cancer cells.

OBJECTIVE: In vitro studies have revealed that treatment of various human cancer cell lines with specific cyclo-oxygenase 2 (COX-2) inhibitors induces apoptotic cell death. It is currently proposed that the combination of COX-2 inhibitors with chemotherapeutic agents improves the efficacy of cancer treatment. MATERIALS AND METHODS: In this study we sought to determine the effects of combining paclitaxel and the COX-2 inhibitor NS398 on apoptosis of epithelial ovarian cancer (EOC) cells. Two EOC cell lines, SKOV3 and MDAH2774, were exposed to increasing concentrations of paclitaxel (0.1, 10, and 100 microM) and NS398 (10, 100 microM) as well as a combination of both drugs. Apoptosis was evaluated by the Tunel assay. The fluorescein-labeled DNA was visualized directly by fluorescence microscopy and quantitated by flow cytometry. RESULTS: While NS398 did not significantly alter apoptosis of either EOC cell lines after 24 h of continuous exposure, treatment of both cell lines with paclitaxel resulted in a significant increase in the rate of apoptosis (60-70%). Concomitant treatment of both SKOV3 and MDAH2774 cells with paclitaxel and NS398 resulted in marked impairment of paclitaxel-induced apoptosis. Similarly, sequential treatment during which both cell lines were treated with NS398 for 4 h, triple-washed, and then exposed to paclitaxel for 24 h resulted in a significant inhibition of paclitaxel-induced apoptosis. Similar inhibition was seen when NS398 was replaced by aspirin. CONCLUSIONS: Combining COX-2 inhibitors and paclitaxel does not have an additive or synergistic tumoricidal effect. On the contrary, NS398 treatment markedly inhibited the apoptotic effects of paclitaxel in each of these two EOC cell lines.

Prognostic significance of residual disease in patients with stage IV epithelial ovarian cancer.

PURPOSE: To evaluate the role of surgical debulking in patients with stage IV ovarian cancer. METHODS: We conducted a retrospective review of patients with advanced epithelial ovarian cancer treated at M. D. Anderson Cancer Center. Eligible patients included women with stage IV disease treated with platinum-based chemotherapy. Surgical debulking was considered optimal if the diameter of the largest residual tumor was 2 cm or less. Survival analysis and comparisons were performed using the Kaplan-Meier method and the log-rank test. RESULTS: One hundred eight women with stage IV ovarian cancer were identified. The extraperitoneal metastatic sites were the liver parenchyma in 16 patients, the pleura in 54 patients, a variety of other organs in 22, and two or more sites in the remaining 16. Median age of the patient population was 58 years (range 35-81 years). Surgery to reduce the primary tumor was performed in 100 patients. The procedures included salpingo-oophorectomy with or without hysterectomy in 94 patients, omentectomy in 90, small bowel resection in 4, large bowel resection in 23, and splenectomy in 2. At the completion of surgery, tumor reduction was considered optimal in 31 patients, suboptimal in 61, and undetermined in 8. The overall median survival for optimally debulked patients was 25 months compared to 15 months for suboptimally debulked patients (P < 0.02). The progression-free survival, on the other hand, was not statistically different between the two groups. CONCLUSION: Residual tumor seems to be an important prognostic factor in patients with stage IV ovarian cancer. Surgical debulking may play a significant role in the treatment of these patients.