Update on the treatment of cervical and uterine carcinoma: focus on topotecan

Paclitaxel, topotecan, and carboplatin in metastatic endometrial cancinoma: a Hellenic Co-operative Oncology Group (HeCOG) study

OBJECTIVE

Taxanes, and platinum compounds represent the chemotherapeutic agents with the greatest activity in metastatic endometrial carcinoma. We administered the combination of paclitaxel, topotecan and carboplatin to patients with metastatic or recurrent carcinoma of the endometrium to evaluate its activity and to define its toxicity.

METHODS

Thirty-nine consecutive patients were treated on an outpatient basis with paclitaxel 150 mg/m(2), administered intravenously over a 3-h period and followed by carboplatin at AUC of 5 on day 3, with both agents proceding topotecan that was given at 0.75 mg/m(2)/day on days 1 through 3. The chemotherapy was repeated every 3 weeks with granulocyte colony-stimulating factor (G-CSF) support for a maximum of six courses.

RESULTS

Twenty-one (60%) patients achieved objective clinical response (95% CI, 42.2-75.7%) including 4 (11.4%) complete and 17 (48.6%) partial responses. The median times to progression and survival for all patients were 8.9 and 17.7 months, respectively. Grade 3 or 4 thombocytopenia and neutropenia occurred in 5 (13%) and 4 (10%) patients, respectively, but only 2 episodes of neutropenic fever were encountered. Grade 2 or 3 neurotoxicity was observed in 23% of patients.

CONCLUSIONS

The combination of paclitaxel, topotecan and carboplatin with G-CSF support appears active with acceptable toxicity in patients with metastatic or recurrent carcinoma of the endometrium.

Chemotherapy for recurrent cervical cancer

OBJECTIVE

To give an overview of chemotherapy schemes used in recurrent cervical cancer.

METHODS

A pubmed search was performed using chemotherapy and recurrent cervical cancer including articles until April 2007.

RESULTS

Most recent articles and articles of interest are discussed.

CONCLUSION

Single agent cisplatin (50 mg/m2) remains the current standard for recurrent cervical cancer. Numerous chemotherapeutic agents have been tested but did not show convincing evidence of improved survival rates, except for the GOG 179 study which showed an improved survival for the combination of cisplatin and topotecan compared with single agent cisplatin. However, nearly 60% of patients in both groups received prior cisplatinum therapy as a radiosensitizer, which could be responsible for the development of platinum resistance, causing lower response and survival rates in the single platinum group. Hence, the apparent benefit in the doublet group is maybe just a reflection from the change in primary therapy and patient population. It is hoped that current trials comparing standard therapy with other single or doublet chemotherapeutic regimens or that the use of molecular-targeted agents will give us promising therapeutic options in the future.

Targeting the heat shock factor 1 by RNA interference: a potent tool to enhance hyperthermochemotherapy efficacy in cervical cancer

Carcinoma of the uterine cervix is one of the highest causes of mortality in female cancer patients worldwide, and improved treatment options for this type of malignancy are highly needed. Local hyperthermia has been successfully used in combination with systemic administration of cisplatin-based chemotherapy in phase I/II clinical studies. Heat-induced expression of cytoprotective and antiapoptotic heat shock proteins (HSP) is a known complication of hyperthermia, resulting in thermotolerance and chemoresistance and hindering the efficacy of the combination therapy. Heat shock transcription factor 1 (HSF1) is the master regulator of heat-induced HSP expression. In the present report, we used small interfering RNA (siRNA) to silence HSF1 and to examine the effect of HSF1 loss of function on the response to hyperthermia and cisplatin-based chemotherapy in HeLa cervical carcinoma. We have identified the 322-nucleotide to 340-nucleotide HSF1 sequence as an ideal target for siRNA-mediated HSF1 silencing, have created a pSUPER-HSF1 vector able to potently suppress the HSF1 gene, and have generated for the first time human cancer cell lines with stable loss of HSF1 function. We report that, although it surprisingly does not affect cancer cell sensitivity to cisplatin or elevated temperatures up to 43 degrees C when administered separately, loss of HSF1 function causes a dramatic increase in sensitivity to hyperthermochemotherapy, leading to massive (>95%) apoptosis of cancer cells. These findings indicate that disruption of HSF1-induced cytoprotection during hyperthermochemotherapy may represent a powerful strategy to selectively amplify the damage in cancer cells and identify HSF1 as a promising therapeutic target in cervical carcinoma.

Surgery after concurrent chemoradiotherapy and brachytherapy for the treatment of advanced cervical cancer: morbidity and outcome: results of a multicenter study of the GCCLCC (Groupe des Chirurgiens de Centre de Lutte Contre le Cancer)

OBJECTIVES

To evaluate the morbidity and therapeutic value of surgery after concurrent chemoradiotherapy and brachytherapy in a multicentric series of patients with advanced cervical cancer.

METHODS

Patients with stage IB2 to IVA cervical cancer treated with concurrent chemoradiotherapy and pelvic radiotherapy followed by brachytherapy and surgery from seven participating French comprehensive cancer centers were enrolled. The surgical treatment consisted of a hysterectomy, which ranged from radical hysterectomy to anterior pelvic exenteration, and lymph node resection. Acute toxicity, pathological response, overall, and disease-free survival were assessed for each pathological response to therapy.

RESULTS

One hundred seventy-five patients were enrolled from September 1987 to June 2002. The median age was 44 years [27;75]. Patients distribution according to clinical classification was as follows: 41 stage IB2, 18 IIA, 77 IIB, 12 IIIA, 14 IIIB, and 13 IVA. Forty-six patients experienced 51 postoperative complications. Thirty-three patients experienced grade 2 morbidity (18.9%, 33/175), among whom 19 experienced urinary complications (57.5%, 19/175). No post treatment mortality was observed. Grade 3 toxicity rate was 6.9% (12/175). Pathological complete response rate was 38% (67/175). After a median follow-up of 36 months, overall survival and disease-free survival were significantly better in patients who had a pathological complete response to therapy than those who achieved a partial pathological response (P < 0.0001).

CONCLUSION

Surgery after concurrent chemoradiotherapy and brachytherapy for advanced cervical cancer leads to an acceptable morbidity. Furthermore, surgery allows evaluation of the pathological response to therapy and improves local control in the case of partial pathological response.

Cell cycle effects of topotecan alone and in combination with irradiation

BACKGROUND AND PURPOSE

To elucidate the role of TP53 on differential effects of topoisomerase I inhibitor topotecan (Hycamtin on radiation sensitivity.

MATERIALS AND METHODS

Cell cycle distribution and protein expression of TP53, p21(WAF1/CIP1) and cyclin B was studied in CCD32 lung fibroblasts, glioblastoma cell lines U118 (mutant TP53), and U87 (wildtype TP53) after treatment with topotecan (0.05 and 1 microM) and/or ionizing radiation (2 Gy).

RESULTS

Cell cycle effects varied with topotecan concentration, resulting in G1 arrest (1 microM), or S/G2/M arrest (0.05 microM), and was modified differentially in fibroblasts and in glioblastoma cells in combination with irradiation. Phosphorylation of TP53 and expression of p21(WAF1/CIP1) was induced by IR and/or topotecan in CCD32 cells, and in U118 cells after topotecan treatment, accompanied by cyclin B degradation. In U87 cells only 1 microM topotecan generated phosphorylation of TP53 and p21(WAF1/CIP1) expression; 0.05 microM caused stabilization of cyclin B.

CONCLUSIONS

The antagonistic effect of combined topotecan/irradiation treatment in fibroblasts was most likely due to an immediate radiation induced G1 arrest, but was not observed in p53 wildtype glioblastoma cells. Thus, the impact of TP53 on the topotecan response remains indistinct, and is obviously influenced by other genomic alterations acquired by tumor cells.

Platinated DNA adducts enhance poisoning of DNA topoisomerase I by camptothecin

Camptothecins constitute a novel class of chemotherapeutics that selectively target DNA topoisomerase I (Top1) by reversibly stabilizing a covalent enzyme-DNA intermediate. This cytotoxic mechanism contrasts with that of platinum drugs, such as cisplatin, which induce inter- and intrastrand DNA adducts. In vitro combination studies using platinum drugs combined with Top1 poisons, such as topotecan, showed a schedule-dependent synergistic activity, with promising results in the clinic. However, whereas the molecular mechanism of these single agents may be relatively well understood, the mode of action of these chemotherapeutic agents in combination necessitates a more complete understanding. Indeed, we recently reported that a functional homologous recombination pathway is required for cisplatin and topotecan synergy yet represses the synergistic toxicity of 1-beta-D-arabinofuranosyl cytidine in combination with topotecan (van Waardenburg, R. C., de Jong, L. A., van Delft, F., van Eijndhoven, M. A., Bohlander, M., Bjornsti, M. A., Brouwer, J., and Schellens, J. H. (2004) Mol. Cancer Ther. 3, 393-402). Here we provide direct evidence for Pt-1,3-d(GTG) poisoning of Top1 in vitro and demonstrate that persistent Pt-DNA adducts correlate with increased covalent Top1-DNA complexes in vivo. This contrasts with a lack of persistent lesions induced by the alkylating agent bis[chloroethyl]nitrosourea, which exhibits only additive activity with topotecan in a range of cell lines. In human IGROV-1 ovarian cancer cells, the synergistic activity of cisplatin with topotecan requires processive DNA polymerization, whereas overexpression of Top1 enhances yeast cell sensitivity to cisplatin. These results indicate that the cytotoxic activity of cisplatin is due, in part, to poisoning of Top1, which is exacerbated in the presence of topotecan.

Weekly topotecan for recurrent endometrial cancer: a case series and review of the literature

OBJECTIVE

Topotecan, a topoisomerase 1 inhibitor, has demonstrated antitumor activity in ovarian and endometrial cancers when administered daily for 5 days every 3 weeks. Recently, topotecan has been studied on a weekly dosing schedule for the treatment of ovarian cancer and found to have efficacy with reduced toxicity. The aim of this study is to review the Memorial Sloan-Kettering Cancer Center (MSKCC) experience with weekly topotecan dosing in women with recurrent endometrial cancer. We have included a review of the literature of weekly topotecan in the treatment of patients with gynecologic cancer.

METHODS

After Institutional Review Board (IRB) approval, we identified all women with recurrent endometrial cancer treated with topotecan at MSKCC from May 1996 to February 2004. Patients treated on a weekly schedule were assessed for toxicity and response. A review of the literature pertaining to weekly topotecan in the treatment of endometrial cancer was also performed.

RESULTS

Eleven patients were treated with weekly topotecan during the study period, with doses ranging from 2.5-4.0 mg/m(2) on a 2- or 3-week schedule with 1 week off. The median age of the patients was 60 years old (range, 47-76 years), and the median Karnofsky performance status was 80%. Six of the 11 patients were previously treated with more than three chemotherapy regimens and eight had received prior pelvic radiation. Ninety-seven percent of treatment doses were delivered as scheduled, and only two patients required dose reductions. One patient achieved a prolonged partial response for 54 weeks, and two patients had stabilization of disease for 15 weeks each.

CONCLUSIONS

Weekly topotecan has antitumor activity and is well tolerated in patients with recurrent endometrial cancer, including those patients with multiple prior treatments. Topotecan on a weekly bolus schedule should be evaluated in prospective trials to better establish its role in the treatment of recurrent endometrial cancer.

The role of topotecan in the treatment of advanced cervical cancer

Improvements in the early detection of cervical cancer have markedly reduced associated mortality rates over the past few decades; however, in patients diagnosed with cervical cancer the rates have remained unchanged for 25 years. Hysterectomy, alone or with radiotherapy, is effective in early-stage disease, with a high cure rate, but the treatment of advanced and recurrent cervical cancer (usually with radiotherapy and cisplatin) is suboptimal, with 5-year survival rates of 50.9 and 16.5% for patients with regional involvement or distant disease, respectively. There is therefore an unmet need for more effective treatments for patients with advanced disease, and a number of new chemotherapy agents and treatment strategies have been investigated in this setting. Promising results have been reported in phase II trials of the topoisomerase inhibitor I, topotecan. Response rates of up to 19% have been reported in patients treated with topotecan as a single agent and response rates of up to 54% have been achieved when this agent is used in combination chemotherapy regimens. Toxicity levels are similar to those observed in patients with relapsed ovarian cancer and are not significantly different from levels with other chemotherapy agents. This paper reviews the current management of advanced cervical cancer and summarizes the available data on the use of topotecan in this setting.

New approaches for the management of cervical cancer

Since the introduction of the Pap test by George Papanicolaou, the incidence of cervical cancer has fallen and mortality has decreased, in parallel with effective treatment of the precancerous and in situ stages of the disease. However, women who are not diagnosed through screening usually present with advanced disease. Early invasive disease can be treated successfully with radical abdominal hysterectomy and pelvic lymphadenectomy or with radiotherapy. A surgical alternative is radical trachelectomy, which can preserve fertility in young women. Advances in the techniques of laparoscopy facilitate procedures, such as radical vaginal hysterectomy with laparoscopic lymphadenectomy, that decrease intra-abdominal scarring and length of hospital stays. The presence of lymph node metastases alters the type of therapy. A range of methods is available to assess lymph nodes, including positron emission tomography, a new approach that may be of value. Radiotherapy alone may not be successful in women with locally advanced disease and adding chemotherapy may eradicate systemic micrometastases that are not affected by radiation. Single-agent cisplatin is the current agent of choice for adding to radiotherapy but new agents are being evaluated. Persistent infection with human papillomavirus (HPV) is associated with the development of cervical cancer. Vaccines against HPV are being developed and clinically tested and hopefully in the future it may be possible to eradicate cervical cancer.