Ethnicity is a factor to be considered before dose planning in ovarian cancer patients to be treated with topotecan

HIF1α is an independent prognostic factor for overall survival in advanced primary epithelial ovarian cancer - a study of the OVCAD Consortium

PURPOSE

Hypoxia is a common phenomenon encountered in solid cancers, leading to chemotherapy resistance and therefore to aggressiveness of the disease. The homeostatic response to hypoxia is mediated by hypoxiainducible factor-1 (HIF-1). The aim of this study was to investigate the impact of HIF1α in patients with primary epithelial ovarian cancer.

METHODS

In this multicentric study, 275 patients with advanced primary epithelial ovarian cancer were included. All patients underwent cytoreductive surgery with maximal surgical effort and adjuvant platinum-based chemotherapy. HIF1α expression was analyzed in tissue lysates, using an enzyme-linked immunosorbent assay.

RESULTS

HIF1α was detected in 79.3% of the tissue samples. Patients with increased HIF1α expression (cutoff: 80 pg/mg protein) in tumoral tissue lysates were more likely to have less favorable survival. HIF1α (P=0.009, hazard ratio [HR] 2.505, 95% confidence interval [95% CI] 1.252-5.013) together with International Federation of Gynecology and Obstetrics (III versus IV) (P=0.013, HR 0.540, 95% CI 0.332-0.878), histology (P=0.007, HR 2.748, 95% CI 1.315-5.743), presence of peritoneal carcinomatosis (P=0.014, HR 2.176, 95% CI 1.170-4.046), residual tumor mass (P=0.017, HR 1.641, 95% CI 1.091-2.468), and response to platinum-based chemotherapy (P<0.001, HR 8.131, 95% CI 5.13-12.88) were independent prognosis factors for overall survival. The independent prognostic factors for progression-free survival were International Federation of Gynecology and Obstetrics stage (P=0.01), histological subtypes (P=0.016), and presence of peritoneal carcinomatosis (P<0.05).

CONCLUSION

HIF1α overexpression in ovarian cancer is associated with poor overall survival, underlining the importance of hypoxia in this angiogenesis driven disease.

iASPP and chemoresistance in ovarian cancers: effects on paclitaxel-mediated mitotic catastrophe

PURPOSE

iASPP is a specific regulator of p53-mediated apoptosis. Herein, we provided the first report on the expression profile of iASPP in ovarian epithelial tumor and its effect on paclitaxel chemosensitivity.

EXPERIMENTAL DESIGN

Expression and amplification status of iASPP was examined in 203 clinical samples and 17 cell lines using immunohistochemistry, quantitative real-time PCR, and immunoblotting, and correlated with clinicopathologic parameters. Changes in proliferation, mitotic catastrophe, apoptosis, and underlying mechanism in ovarian cancer cells of different p53 status following paclitaxel exposure were also analyzed.

RESULTS

The protein and mRNA expression of iASPP was found to be significantly increased in ovarian cancer samples and cell lines. High iASPP expression was significantly associated with clear cell carcinoma subtype (P = 0.003), carboplatin and paclitaxel chemoresistance (P = 0.04), shorter overall (P = 0.003), and disease-free (P = 0.001) survival. Multivariate analysis confirmed iASPP expression as an independent prognostic factor. Increased iASPP mRNA expression was significantly correlated with gene amplification (P = 0.023). iASPP overexpression in ovarian cancer cells conferred resistance to paclitaxel by reducing mitotic catastrophe in a p53-independent manner via activation of separase, whereas knockdown of iASPP enhanced paclitaxel-mediated mitotic catastrophe through inactivating separase. Both securin and cyclin B1/CDK1 complex were involved in regulating separase by iASPP. Conversely, overexpressed iASPP inhibited apoptosis in a p53-dependent mode.

CONCLUSIONS

Our data show an association of iASPP overexpression with gene amplification in ovarian cancer and suggest a role of iASPP in poor patient outcome and chemoresistance, through blocking mitotic catastrophe. iASPP should be explored further as a potential prognostic marker and target for chemotherapy.

Race does not impact outcome for advanced ovarian cancer patients treated with cisplatin/paclitaxel: an analysis of Gynecologic Oncology Group trials

BACKGROUND

The objectives of this study were to confirm whether racial disparity exists with regard to outcome between black women and white women with ovarian cancer and to identify factors associated with the administration of adjuvant treatment that had an impact on survival.

METHODS

A retrospective review of 97 black women and 1392 white women with International Federation of Gynecology and Obstetrics stage III/IV ovarian carcinoma was performed. All patients received paclitaxel combined with cisplatin while participating in 1 of 7 Gynecologic Oncology Group clinical trials. The treatment parameters that were reviewed included relative dose, relative time, and relative dose intensity. The treatment parameters and outcomes were compared between black patients and white patients.

RESULTS

There were no differences in relative dose (0.90 vs 0.89), relative time (1.02 vs 0.99), or relative dose intensity (0.90 vs 0.91) received between black patients and white patients. Black women had less grade 3 and 4 leukopenia (53% vs 63%; P<.05) and gastrointestinal toxicity (10% vs 19%; P<.05) than white women. Performance status>0, age>or=70 years, and mucinous histology were associated with not completing treatment (P<.001). The median progression-free survival was 16.2 months for black patients and 16.1 months for white patients, and the median overall survival was 37.9 months and 39.7 months, respectively (P>.05 for all).

CONCLUSIONS

When they received similar treatment, there was no difference in clinical outcome between black women and white women with advanced stage epithelial ovarian cancer when they received similar treatment as participants in Gynecologic Oncology Group clinical trials. Black patients may experience less severe gastrointestinal toxicity or leukopenia compared with whites when treated with platinum-based chemotherapy.