Christopher S. Bryant

Lymphadenectomy and ovarian preservation in low-grade endometrial stromal sarcoma.

OBJECTIVE: To report the impact on overall survival of lymphadenectomy and ovarian preservation in patients with endometrial stromal sarcoma. METHODS: Data were extracted from the Surveillance, Epidemiology, and End Results Program from 1988 to 2005. Kaplan-Meier and Cox proportional hazards analyses were used to identify possible predictors for survival. RESULTS: Nine hundred seventy women were reported with endometrial stromal sarcoma. The 384 women with low-grade endometrial stromal sarcoma had a younger age, earlier stage, and longer survival than the 320 women with high-grade lesions. Among the low-grade endometrial stromal sarcoma patients, the incidence of extrauterine disease was 25%, and lymph node metastasis was 7%. Univariable and multivariable analysis demonstrated lymph node metastasis and ovarian preservation were not significant prognostic factors for survival. CONCLUSION: In low-grade endometrial stromal sarcoma, the risk of extrauterine spread and lymph node metastasis merit consideration for surgical staging. Neither lymph node metastasis nor ovarian preservation seems to affect the excellent overall survival of these patients. LEVEL OF EVIDENCE: II

Clinical trials and progress with paclitaxel in ovarian cancer.

Paclitaxel is a front-line agent for ovarian cancer chemotherapy, along with the platinum agents. Derived from the Pacific yew tree, Taxus brevifolia, paclitaxel has covered significant ground from the initial discovery of its antineoplastic properties to clinical applications in many forms of human cancers, including ovarian cancer. Although much has been published about the unique mechanism of action of this agent, several issues remain to be resolved. Finding the appropriate dosage schedule for paclitaxel in chemo-naïve and recurrent ovarian cancer, defining the role of paclitaxel in maintenance chemotherapy, and elucidating the mechanisms of taxane resistance are areas of intense research. Newer forms of taxanes are being manufactured to avoid troublesome adverse effects and to improve clinical efficacy. These issues are reviewed in detail in this paper with an emphasis on clinically relevant evidence-based information.

Ritonavir blocks AKT signaling, activates apoptosis and inhibits migration and invasion in ovarian cancer cells

BackgroundOvarian cancer is the leading cause of mortality from gynecological malignancies, often undetectable in early stages. The difficulty of detecting the disease in its early stages and the propensity of ovarian cancer cells to develop resistance to known chemotherapeutic treatments dramatically decreases the 5-year survival rate. Chemotherapy with paclitaxel after surgery increases median survival only by 2 to 3 years in stage IV disease highlights the need for more effective drugs. The human immunodeficiency virus (HIV) infection is characterized by increased risk of several solid tumors due to its inherent nature of weakening of immune system. Recent observations point to a lower incidence of some cancers in patients treated with protease inhibitor (PI) cocktail treatment known as HAART (Highly Active Anti-Retroviral Therapy).ResultsHere we show that ritonavir, a HIV protease inhibitor effectively induced cell cycle arrest and apoptosis in ovarian cell lines MDH-2774 and SKOV-3 in a dose dependent manner. Over a 3 day period with 20 μM ritonavir resulted in the cell death of over 60% for MDAH-2774 compared with 55% in case of SKOV-3 cell line. Ritonavir caused G1 cell cycle arrest of the ovarian cancer cells, mediated by down modulating levels of RB phosphorylation and depleting the G1 cyclins, cyclin-dependent kinase and increasing their inhibitors as determined by gene profile analysis. Interestingly, the treatment of ritonavir decreased the amount of phosphorylated AKT in a dose-dependent manner. Furthermore, inhibition of AKT by specific siRNA synergistically increased the efficacy of the ritonavir-induced apoptosis. These results indicate that the addition of the AKT inhibitor may increase the therapeutic efficacy of ritonavir.ConclusionOur results demonstrate a potential use of ritonavir for ovarian cancer with additive effects in conjunction with conventional chemotherapeutic regimens. Since ritonavir is clinically approved for human use for HIV, drug repositioning for ovarian cancer could accelerate the process of traditional drug development. This would reduce risks, limit the costs and decrease the time needed to bring the drug from bench to bedside.

The prevalence and prognostic impact of lymph node metastasis in malignant germ cell tumors of the ovary

BACKGROUND The purpose of this study is to report the prevalence and prognostic importance of lymph node metastasis in malignant germ cell tumors of the ovary (OGCT). METHODS Demographic and clinicopathologic information were abstracted from the Surveillance, Epidemiology, and End Results Program (SEER) from 1988 to 2004. Patients with a histologic diagnosis of OGCT after surgical resection were included. The study population was divided into Cohort A (lymph node metastasis absent) and Cohort B (lymph node metastasis present). Statistical analysis using Fishers Exact Test, Kaplan-Meier survival methods, and Cox regression proportional hazards were performed. RESULTS In 613 patients with lymphadenectomy, the prevalence of lymphnode metastasis was 18.1% (111/613). In dysgerminoma, malignant teratoma and mixed germ cell tumors including pure non-dysgerminoma histology, the lymphnode metastasis was present in 28%, 8% and 16% patients respectively (p<0.05). Age, race, grade and extent of lymph node dissection influenced lymph node involvement but this was statistically not significant. Five year survival in Cohort A was 95.7% compared to 82.8% in Cohort B (p<0.001). After controlling for age, race, stage, grade and histology, multivariate analysis revealed the presence of lymph node involvement as an independent predictor of poor survival with a hazards ratio of 2.87 (95% CI 1.439-5.725; p<0.05). CONCLUSIONS Prevalence of lymph node metastasis varies according to histology in OGCT and is an independent predictor of poor survival in these patients. These findings highlight the value of lymphadenectomy and may be helpful in creating risk stratification models for individualization of adjuvant therapies.

Sulforaphane induces cell cycle arrest by protecting RB-E2F-1 complex in epithelial ovarian cancer cells

BackgroundSulforaphane (SFN), an isothiocyanate phytochemical present predominantly in cruciferous vegetables such as brussels sprout and broccoli, is considered a promising chemo-preventive agent against cancer. In-vitro exposure to SFN appears to result in the induction of apoptosis and cell-cycle arrest in a variety of tumor types. However, the molecular mechanisms leading to the inhibition of cell cycle progression by SFN are poorly understood in epithelial ovarian cancer cells (EOC). The aim of this study is to understand the signaling mechanisms through which SFN influences the cell growth and proliferation in EOC.ResultsSFN at concentrations of 5 - 20 μM induced a dose-dependent suppression of growth in cell lines MDAH 2774 and SkOV-3 with an IC50 of ~8 μM after a 3 day exposure. Combination treatment with chemotherapeutic agent, paclitaxel, resulted in additive growth suppression. SFN at ~8 μM decreased growth by 40% and 20% on day 1 in MDAH 2774 and SkOV-3, respectively. Cells treated with cytotoxic concentrations of SFN have reduced cell migration and increased apoptotic cell death via an increase in Bak/Bcl-2 ratio and cleavage of procaspase-9 and poly (ADP-ribose)-polymerase (PARP). Gene expression profile analysis of cell cycle regulated proteins demonstrated increased levels of tumor suppressor retinoblastoma protein (RB) and decreased levels of E2F-1 transcription factor. SFN treatment resulted in G1 cell cycle arrest through down modulation of RB phosphorylation and by protecting the RB-E2F-1 complex.ConclusionsSFN induces growth arrest and apoptosis in EOC cells. Inhibition of retinoblastoma (RB) phosphorylation and reduction in levels of free E2F-1 appear to play an important role in EOC growth arrest.

MicroRNA-101 Inhibits Growth of Epithelial Ovarian Cancer by Relieving Chromatin-Mediated Transcriptional Repression of p21 waf1/cip1

ABSTRACTPurposeMicroRNA-101 (miR-101) expression is negatively associated with tumor growth and proliferation in several solid epithelial cancers. Enhancer of zeste homolog 2 (EzH2) appears to be a functional target of miR-101. We explore the role of miR-101 and its interaction with EzH2 in epithelial ovarian carcinoma (EOC).MethodsIn situ hybridization (ISH) for miR-101 was performed on EOC patient tissues and normal controls. EOC cell lines were transfected with miR-101 and subjected to growth analysis and clonogenic assays. Cell motility was assessed by Boyden chamber and wound-healing assays. P21waf1/cip1 and EzH2 interaction was assessed by Chromatin Immunoprecipitation (ChIP) assay in MDAH-2774 cells. SCID mice were assessed for tumor burden after injection with miR-101 or control vector-treated MDAH-2774 cells.ResultsISH analysis revealed a decrease in miR-101 expression in EOC compared with normal tissue. MiR-101 re-expression in EOC cell lines resulted in increased apoptosis, decreased cellular proliferation, invasiveness, and reduced growth of tumor xenografts. CHIP assays revealed that re-expression of miR-101 inhibited the interaction of EzH2 with p21waf1/cip1 promoter.ConclusionsMiR-101 re-expression appears to have antitumor effects, providing a better understanding of the role of miR-101 in EOC.

Chk1 Inhibition as a novel therapeutic strategy for treating triple-negative breast and ovarian cancers

BackgroundChk1 inhibitors are currently in clinical trials as putative potentiators of cytotoxic chemotherapy drugs. Chk1 inhibitors may exhibit single agent anti-tumor activity in cancers with underlying DNA repair, DNA damage response or DNA replication defects.MethodsHere we describe the cellular effects of the pharmacological inhibition of the checkpoint kinase Chk1 by the novel inhibitor V158411 in triple-negative breast cancer and ovarian cancer. Cytotoxicity, the effect on DNA damage response and cell cycle along with the ability to potentiate gemcitabine and cisplatin cytotoxicity in cultured cells was investigated. Western blotting of proteins involved in DNA repair, checkpoint activation, cell cycle and apoptosis was used to identify potential predictive biomarkers of Chk1 inhibitor sensitivity.ResultsThe Chk1 inhibitors V158411, PF-477736 and AZD7762 potently inhibited the proliferation of triple-negative breast cancer cells as well as ovarian cancer cells, and these cell lines were sensitive compared to ER positive breast and other solid cancer cells lines. Inhibition of Chk1 in these sensitive cell lines induced DNA damage and caspase-3/7 dependent apoptosis. Western blot profiling identified pChk1 (S296) as a predictive biomarker of Chk1 inhibitor sensitivity in ovarian and triple-negative breast cancer and pH2AX (S139) in luminal breast cancer.ConclusionsThis finding suggests that Chk1 inhibitors either as single agents or in combination chemotherapy represents a viable therapeutic option for the treatment of triple-negative breast cancer. pChk1 (S296) tumor expression levels could serve as a useful biomarker to stratify patients who might benefit from Chk1 inhibitor therapy.

Stage IA vs. IB endometrial stromal sarcoma: Does the new staging system predict survival?

OBJECTIVE To determine the correlation of the new FIGO staging system with survival in stage I patients with low-grade and high-grade endometrial stromal sarcomas. METHODS Data were extracted from the Surveillance, Epidemiology, and End Results database between 1988 and 2005. Kaplan-Meier log rank and Cox proportional hazards models were used for survival analysis and to identify possible predictors for survival. RESULTS The identified cohort included 464 women, 310 (67%) low-grade endometrial stromal sarcoma, 96 (21%) high-grade endometrial stromal sarcoma, and 58 (12%) unclassified endometrial stromal sarcoma. Among low-grade and high-grade endometrial stromal sarcomas, there was no significant demographic or clinico-pathologic difference between stages IA and IB. The 5-year overall survival was worse in high-grade endometrial stromal sarcoma than low-grade endometrial stromal sarcoma (45.4% vs. 97.2%, p<0.001). The difference in 5-year overall survival among women with low-grade endometrial stromal sarcoma between stages IA and IB was significant (100% vs. 93.5%, p=0.003), but not among women with high-grade endometrial stromal sarcoma (51.4% vs. 43.5%, p=0.27). Although age (p=0.001), race (p=0.005), and stage (p=0.004) were all significant prognostic factors in low-grade endometrial stromal sarcoma, only cervical involvement (p=0.02) was a significant predictor in high-grade endometrial stromal sarcoma. CONCLUSION The new staging system is appropriate for risk stratification in low-grade endometrial stromal sarcoma. The prognosis in high-grade endometrial stromal sarcoma seems to be most influenced by the presence of cervical involvement and not by tumor size as the staging criteria would suggest.

Ovarian and uterine carcinosarcomas: A comparative analysis of prognostic variables and survival outcomes

Introduction: Carcinosarcomas (malignant mixed Mullerian tumor) of the female genital tract are rare tumors associated with poor outcome. The objective of this study was to identify site-specific differences by comparing carcinosarcomas originating in the uterus and the ovaries. Methods: Data on patients with uterine and ovarian carcinosarcomas were extracted from the Surveillance, Epidemiology, and End Results database between 1988 and 2005. Kaplan-Meier log rank and Cox proportional hazards models were used for survival analysis and for identification of possible predictors for survival. Results: The identified cohort included 3683 women of whom 2759 (75%) have uterine carcinosarcoma and 924 (25%) have ovarian carcinosarcomas. The patients with uterine carcinosarcoma were older than the patients with ovarian carcinosarcoma (median age, 67 vs 65 years; P < 0.001). The women with uterine carcinosarcoma compared with those with ovarian carcinosarcoma were more often African American (17.3% vs 6%; P < 0.001) and presented more often with localized disease (47% vs 10.8%; P < 0.001). Uterine carcinosarcoma compared with ovarian carcinosarcoma differed significantly with regard to the performance of lymphadenectomy (62.6% vs 41.2%; P < 0.001) and the administration of radiotherapy (38.2% vs 4.8%; P < 0.001). When controlled for the extent of disease spread, uterine carcinosarcoma had a more aggressive clinical course and shorter survival compared with ovarian carcinosarcoma. Although age (P < 0.001), race (P = 0.01), stage (P < 0.001), lymphadenectomy (P < 0.001), and radiation (P < 0.001) were all significant prognostic factors in uterine carcinosarcoma, only age (P < 0.001), stage (P < 0.001), and lymphadenectomy (P < 0.001) were significant predictors in ovarian carcinosarcoma. Conclusion: Although uterine carcinosarcoma presents at an earlier stage than ovarian carcinosarcoma, it has a worse prognosis compared with ovarian carcinosarcoma, with a similar extent of disease spread. Improved survival observed in lymphadenectomy group lends support to its routine performance in patients with uterine and ovarian carcinosarcomas.

A comparison of younger vs older women with vulvar cancer in the United States.

OBJECTIVE The purpose of this study was to compare the prognostic variables and survival of younger (< 50 years) to that of older (> or = 50 years) women with vulvar cancer. STUDY DESIGN Subjects with invasive squamous cell carcinoma of the vulva were identified from the limited use Surveillance, Epidemiology, and End Results (SEER) Program 1988-2005. Comparisons between younger and older women were accomplished with chi(2) and t-tests. Survival analysis was accomplished with Kaplan-Meier for univariate analysis and Cox proportional hazards model for multivariate analysis. RESULTS A total of 6965 patients met inclusion criteria, of whom 1345 patients (19.3%) were younger and 5620 patients (80.7%) were older. The 5-year survival was 87.5% for younger women and 52.5% for older women (P < .001). After data were controlled for race, stage, grade, and surgical treatment, older patients had a hazard ratio of 3.9 (95% CI, 3.2-4.7) for death. CONCLUSION A striking survival difference exists between younger and older women with squamous cell vulvar cancer, which supports the view that etiopathogenesis of this disease may vary between age groups.