Topotecan combined with carboplatin in recurrent epithelial ovarian cancer: Results of a single-institutional phase II study

Real world effectiveness and safety of pegylated liposomal doxorubicin in platinum-sensitive recurrent ovarian, fallopian, or primary peritoneal cancer: a Korean multicenter retrospective cohort study

OBJECTIVE

To evaluate the effectiveness and safety of the combination of pegylated liposomal doxorubicin with carboplatin (CD) compared with those of carboplatin and paclitaxel (CP) for platinum-sensitive recurrent ovarian, fallopian, or primary peritoneal cancer in a real-world setting in Korea.

METHODS

We enrolled relevant patients from 9 institutions. All patients received CD or CP as the second- or third-line chemotherapy in routine clinical practice during 2013-2018. The primary endpoints were progression-free survival (PFS) and toxicity. The secondary endpoint included the objective response rate (ORR).

RESULTS

Overall, 432 patients (224 and 208 in the CD and CP groups, respectively) were included. With a median follow-up of 18.9 months, the median PFS was not different between the groups (12.7 vs. 13.6 months; hazard ratio, 1.161; 95% confidence interval, 0.923-1.460; p=0.202). The ORR was 74.6% and 80.1% in the CD and CP group, respectively (p=0.556). Age and surgery at relapse were independent prognostic factors. More patients in the CD group significantly experienced a grade 3 to 4 hematologic toxicity and hand-foot syndrome (13.8% vs. 6.3%), whereas grade 2 or more alopecia (6.2% vs. 36.1%), peripheral neuropathy (4.4% vs. 11.4%), and allergic/hypersensitivity reaction (0.4% vs. 8.5%) developed more often in the CP group.

CONCLUSIONS

The safety and effectiveness of chemotherapy with CD in a real-world setting were consistent with the results from a randomized controlled study. The different toxicity profiles between the 2 chemotherapy (CD and CP) regimens should be considered in the clinical practice.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03562533.

Phase II activity of belinostat (PXD-101), carboplatin, and paclitaxel in women with previously treated ovarian cancer

BACKGROUND

Preclinical data show that belinostat (Bel) is synergistic with carboplatin and paclitaxel in ovarian cancer. To further evaluate the clinical activity of belinostat, carboplatin, and paclitaxel (BelCaP), a phase 1b/2 study was performed, with an exploratory phase 2 expansion planned specifically for women with recurrent epithelial ovarian cancer (EOC).

METHODS

Thirty-five women were treated on the phase 2 expansion cohort. BelCap was given as follows: belinostat, 1000 mg/m² daily for 5 days with carboplatin, AUC 5; and paclitaxel, 175 mg/m² given on day 3 of a 21-day cycle. The primary end point was overall response rate (ORR), using a Simon 2 stage design.

RESULTS

The median age was 60 years (range, 39-80 years), and patients had received a median of 3 prior regimens (range, 1-4). Fifty-four percent had received more than two prior platinum-based combinations, sixteen patients (46%) had primary platinum-resistant disease, whereas 19 patients (54%) recurred within 6 months of their most recent platinum treatment. The median number of cycles of BelCaP administered was 6 (range, 1-23). Three patients had a complete response, and 12 had a partial response, for an ORR of 43% (95% confidence interval, 26%-61%). When stratified by primary platinum status, the ORR was 44% among resistant patients and 63% among sensitive patients. The most common drug-related adverse events related to BelCaP were nausea (83%), fatigue (74%), vomiting (63%), alopecia (57%), and diarrhea (37%). With a median follow-up of 4 months (range, 0-23.3 months), 6-month progression-free survival is 48% (95% confidence interval, 31%-66%). Median overall survival was not reached during study follow-up.

CONCLUSIONS

Belinostat, carboplatin, and paclitaxel combined was reasonably well tolerated and demonstrated clinical benefit in heavily-pretreated patients with EOC. The addition of belinostat to this platinum-based regimen represents a novel approach to EOC therapy and warrants further exploration.

Low or undetectable TPO receptor expression in malignant tissue and cell lines derived from breast, lung, and ovarian tumors

BACKGROUND

Numerous efficacious chemotherapy regimens may cause thrombocytopenia. Thrombopoietin receptor (TPO-R) agonists, such as eltrombopag, represent a novel approach for the treatment of chemotherapy-induced thrombocytopenia. The TPO-R MPL is expressed on megakaryocytes and megakaryocyte precursors, although little is known about its expression on other tissues.

METHODS

Breast, lung, and ovarian tumor samples were analyzed for MPL expression by microarray and/or quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and for TPO-R protein expression by immunohistochemistry (IHC). Cell line proliferation assays were used to analyze the in vitro effect of eltrombopag on breast, lung, and ovarian tumor cell proliferation. The lung carcinoma cell lines were also analyzed for TPO-R protein expression by Western blot.

RESULTS

MPL mRNA was not detectable in 118 breast tumors and was detectable at only very low levels in 48% of 29 lung tumors studied by microarray analysis. By qRT-PCR, low but detectable levels of MPL mRNA were detectable in some normal (14-43%) and malignant (3-17%) breast, lung, and ovarian tissues. A comparison of MPL to EPOR, ERBB2, and IGF1R mRNA demonstrates that MPL mRNA levels were far lower than those of EPOR and ERBB2 mRNA in the same tissues. IHC analysis showed negligible TPO-R protein expression in tumor tissues, confirming mRNA analysis. Culture of breast, lung, and ovarian carcinoma cell lines showed no increase, and in fact, showed a decrease in proliferation following incubation with eltrombopag. Western blot analyses revealed no detectable TPO-R protein expression in the lung carcinoma cell lines.

CONCLUSIONS

Multiple analyses of breast, lung, and ovarian tumor samples and/or cell lines show no evidence of MPL mRNA or TPO-R protein expression. Eltrombopag does not stimulate growth of breast, lung, or ovarian tumor cell lines at doses likely to exert their actions on megakaryocytes and megakaryocyte precursors.

Topotecan as a molecular targeting agent which blocks the Akt and VEGF cascade in platinum-resistant ovarian cancers

OBJECTIVE

Topotecan, a novel topoisomerase-1 inhibitor, is a drug that appears to be effective against platinum-resistant ovarian cancers. However, the molecular mechanisms by which Topotecan treatment inhibits cancer cell proliferation are unclear. We investigated whether Topotecan increases the efficacy of Cisplatin in platinum-resistant ovarian cancer models in vitro and in vivo.

METHODS

We used Cisplatin-resistant Caov-3 cells and Cisplatin-sensitive A2780 cells. We examined the effect of Cisplatin and Topotecan on the cell viability of Caov-3 and A2780 cells by MTS assay. We examined the Akt kinase activity, VEGF and HIF-1α expression after Cisplatin and Topotecan by a Western blot analysis. Moreover, we also evaluated the effects of Cisplatin and Topotecan on the intraabdominal dissemination of ovarian cancer in vivo.

RESULTS

Topotecan significantly inhibited Cisplatin-induced Akt activation in Caov-3 cells, but not in A2780 cells. In the presence of Topotecan, Cisplatin-induced growth inhibition and apoptosis were significantly enhanced in Caov-3 cells. Topotecan inhibited not only Cisplatin-induced Akt activation but also VEGF and HIF-1α expression. Moreover, treatment with Topotecan increased the efficacy of Cisplatin-induced growth inhibition in the intraabdominal dissemination and production of ascites in athymic nude mice inoculated with Caov-3 cells.

CONCLUSION

We herein demonstrated that Topotecan inhibits Akt kinase activity and VEGF transcriptional activation after Cisplatin treatment in platinum-resistant ovarian cancers. We clarified how Topotecan enhanced the clinical activity in the platinum-resistant ovarian cancer. These results provide a rationale for using Topotecan in clinical regimens aimed at molecular targeting agents in platinum-resistant ovarian cancers.