Improving first-line therapy of advanced ovarian cancer - the AGO Ovarian Cancer Study Group perspective

RNAi screening of the kinome identifies modulators of cisplatin response in ovarian cancer cells

OBJECTIVE

Ovarian cancer retains a poor prognosis among the female gynaecological malignancies. It constitutes about 3% of all malignancies in women and accounts for 5% of all female cancer related deaths. A standard treatment is cytoreductive surgery followed by adjuvant chemotherapy, and re-treatment with platinum based chemotherapy at the time of relapse. In order to improve cisplatin response in ovarian cancer cells, we utilized a high-throughput RNAi screening to identify kinase modulators.

METHODS

A high-throughput RNAi screen was performed using a siRNA library targeting 572 kinases to identify potentiators of cisplatin response in the ovarian cancer cell line SKOV3.

RESULTS

RNAi screening identified at least 55 siRNAs that potentiated the growth inhibitory effects of cisplatin in SKOV3 cells. Inhibition of ATR and CHK1 resulted in the greatest modulation of cisplatin response. Drug dose response of cisplatin in the presence of siRNA validated the effects of these target genes. To show that the siRNA data could be successfully translated into potential therapeutic strategies, CHK1 was further targeted with small molecule inhibitor PD 407824 in combination with cisplatin. Results showed that treatment of SKOV3 and OVCAR3 cells with CHK1 inhibitor PD 407824 led to sensitization of ovarian cancer cells to cisplatin.

CONCLUSIONS

Our data provides kinase targets that could be exploited to design better therapeutics for ovarian cancer patients. We also demonstrate the effectiveness of high-throughput RNAi screening as a tool for identifying sensitizing targets to known and established chemotherapeutic agents.

Ten years of “Optimal Therapy in Advanced Ovarian Cancer. Update” Meeting

TheInternational Symposium on Advanced Ovarian Cancer: Optimal Therapywas founded by Dr. Andrés Poveda and Prof. Jan B. Vermorken, and each edition has been directed by them. The 6th edition was held on March 2, 2007. This symposium is organized every other year by GEICO (Grupo Español de Investigación de Cáncer de Ovario/Spanish Ovarian Cancer Research Group), under the auspices of the Spanish Society of Medical Oncology (SEOM), the Gynecologic Cancer Intergroup (GCIG), and the European Society of Medical Oncology (ESMO) Educational Committee for its Medical Oncology Recertification Approval (ESMO/MORA) Program. One hundred and fifty people attended the symposium's 1st edition, held in 1996. Since then, the interest in this meeting has increased. Last year, almost three hundred people coming not only from Spain but also from Europe, North and Latin America, Asia, and Australia were present in the symposium. This is a great challenge for us. Some important international cooperative groups from Europe, America, and Australia collaborate with this symposium, such as GOG, NCIC, EORTC, AGO, Scottish Group, ICON, GINECO, NSGO, ANZGOG, and others.

Optimized sequence of drug administration and schedule leads to improved dose delivery for gemcitabine and paclitaxel in combination: a phase I trial in patients with recurrent ovarian cancer

We examined appropriate sequence, schedule, and doses of gemcitabine (G) and paclitaxel (T) in patients with persistent or recurrent epithelial ovarian cancer. Patients received a maximum of six cycles of gemcitabine on days 1 and 8 (starting 1000 mg/m(2)), and paclitaxel (starting 135 mg/m(2)) on day 8 (groups A and B) or day 1 (group C). Drug sequences (G-->T and T-->G) were tested in group A. In group A, changing sequences of gemcitabine and paclitaxel infusion were evaluated. Sequence G-->T raised grade 3 alanine transaminase in two of three patients leading to use of T-->G sequence for remainder of study. In group B, maximum tolerable dose was reached at gemcitabine 1000 mg/m(2) and paclitaxel 175 mg/m(2). Reducing paclitaxel to 150 mg/m(2) allowed escalation of gemcitabine to 1250 mg/m(2), but neutropenia-related treatment delays occurred. Giving paclitaxel on day 1 (group C) enabled administration of paclitaxel 175 mg/m(2) and gemcitabine 1250 mg/m(2) with minimal dose adjustments. The overall response rate was 41.0%, with 2 complete responses and 14 partial responses in 39 eligible patients. The schedule of paclitaxel 175 mg/m(2) (day 1) and gemcitabine 1250 mg/m(2) (days 1 and 8), with sequence of T-->G, appears most suitable with tolerable toxicity and promising activity.

Ovarian cancer treatment: what is new

Ovarian cancer is still the fourth cause of death by cancer among women and the most fatal among gynecological tumors. The purpose of this symposium is, year after year, to report and discuss the new developments in the treatment of patients with ovarian cancer, the majority of whom still present with advanced disease. It also tries to make it clear to the participants what is evidence-based and what is not. Mature data of both classic studies like GOG-111, OV-10, and more recent studies like GOG-158, AGO-OVAR-3, and the intergroup paclitaxel/epirubicin/carboplatin (TEC) versus paclitaxel/carboplatin (TC) study have been presented. Other current controversial issues included in this edition were sequential single-agent versus simultaneous administration of combination chemotherapy, the role of combination chemotherapy in second-line treatment, the role of consolidation therapy, the role of anthracyclines in the treatment, and cost-effectiviness studies in ovarian cancer. Although the main topic of the symposium is advanced disease, this edition included the results of two parallel randomized studies (ACTION and ICON1) on the treatment of early disease. In addition, new trends in early detection of ovarian cancer have been updated. The pace of new agent development has increased, and it would be helpful to have more efficient preclinical models and early phase-clinical trials to guide the selection of active agents for phase III evaluation. Reaching international consensus is a challenge but offers the opportunity to test multiple regimens more efficiently against a single-control population, rather than conducting multiple smaller studies with redundant internal controls. If indeed answers to the relevant questions are to be obtained more quickly, then, a network of current national or international groups could potentially facilitate this.