Metronomic therapy for gynecologic cancers

Weekly Dose-Dense Paclitaxel and Triweekly Low-Dose Cisplatin: A Well-Tolerated and Effective Chemotherapeutic Regimen for First-Line Treatment of Advanced Ovarian, Fallopian Tube, and Primary Peritoneal Cancer

A combination of cytoreductive surgery, either primary (PCS) or interval (ICS), and chemotherapy with a platinum-paclitaxel regimen is the well-accepted treatment for advanced-stage epithelial ovarian cancer (EOC), fallopian tube cancer (FTC), and primary peritoneal serous carcinoma (PPSC), but it is still uncertain whether a combination of dose-dense weekly paclitaxel and low-dose triweekly cisplatin is useful in the management of these patients. Therefore, we retrospectively evaluated the outcomes of women with advanced-stage EOC, FTC, and PPSC treated with PCS and subsequent dose-dense weekly paclitaxel (80 mg/m²) and low-dose triweekly cisplatin (20 mg/m²). Between January 2011 and December 2017, 32 women with International Federation of Gynecology and Obstetrics (FIGO) stage IIIC–IV EOC, FTC, or PPSC were enrolled. Optimal PCS was achieved in 63.5% of patients. The mean and median progression-free survival was 36.5 and 27.0 months, respectively (95% confidence interval (CI): 26.8–46.2 and 11.3–42.7 months, respectively). The mean overall survival was 56.0 months (95% CI: 43.9–68.1 months), and the median overall survival could not be obtained. The most common all-grade adverse events (AEs) were anemia (96.9%), neutropenia (50%), peripheral neuropathy (28.1%), nausea and vomiting (34.4%), and thrombocytopenia (15.6%). These AEs were predominantly grade 1/2, and only a few patients were complicated by grade 3/4 neutropenia (21.9%) and anemia (6.3%). A multivariate analysis indicated that only suboptimal PCS was significantly correlated with a worse prognosis, resulting in an 11.6-fold increase in the odds of disease progression. In conclusion, our data suggest that dose-dense weekly paclitaxel (80 mg/m²) combined with low-dose triweekly cisplatin (20 mg/m²) is a potentially effective and highly tolerable front-line treatment in advanced EOC, FTC, and PPSC. Randomized trials comparing the outcome of this regimen to other standard therapies for FIGO stage IIIC–IV EOC, FTC, and PPSC are warranted.

Rethinking Alkylating(-Like) Agents for Solid Tumor Management

Although old molecules, alkylating agents and platinum derivatives are still widely used in the treatment of various solid tumors. However, systemic toxicity and cellular resistance mechanisms impede their efficacy. Innovative strategies, including local administration, optimization of treatment schedule/dosage, synergistic combinations, and the encapsulation of bioactive molecules in smart, multifunctional drug delivery systems, have shown promising results in potentiating anticancer activity while circumventing such hurdles. Furthermore, questioning of the old paradigm according to which nuclear DNA is the critical target of their anticancer activity has shed light on subcellular alternative and neglected targets that obviously participate in the mediation of cytotoxicity or resistance. Thus, rethinking of the use of these pivotal antineoplastic agents appears critical to improve clinical outcomes in the management of solid tumors.

Intraperitoneal chemotherapy for ovarian cancer using sustained-release implantable devices

INTRODUCTION

Epithelial ovarian cancer (EOC) remains to be the most lethal of all gynecological malignancies mainly due to its asymptomatic nature. The late stages are manifested with predominant metastases confined to the peritoneal cavity. Although there has been a substantial progress in the treatment avenue with different therapeutic interventions, the overall survival rate of patients remain poor due to relapse and drug resistance.

AREAS COVERED

The pharmacokinetic advantages offered by intraperitoneal (IP) chemotherapy due to peritoneal-plasma barrier can be potentially exploited for EOC relapse treatment. The ability to retain high concentrations of chemo-drugs with high AUC peritoneum/plasma for prolonged durations in the peritoneal cavity can be utilized effectively through the clinical adoption of drug delivery systems (DDSs) which obviates the need for indwelling catheters. The metronomic dosing strategy could enhance anti-tumor efficacy with a continuous, low dose of chemo-drugs providing minimal systemic toxicity.

EXPERT OPINION

The development of a feasible, non-catheter based, IP DDS, retaining the peritoneal-drug levels, with less systemic levels could offer significant survival advantages as a patient-compliant therapeutic strategy. Suturable-implantable devices based on metronomic dosing, eluting drug in a sustained manner at low doses, could be implanted surgically post-debulking for treatment of refractory EOC patients.

The HDACi Panobinostat Shows Growth Inhibition Both In Vitro and in a Bioluminescent Orthotopic Surgical Xenograft Model of Ovarian Cancer

Background

In most epithelial ovarian carcinomas (EOC), epigenetic changes are evident, and overexpression of histone deacetylases (HDACs) represents an important manifestation. In this study, we wanted to evaluate the effects of the novel HDAC inhibitor (HDACi) panobinostat, both alone and in combination with carboplatin, on ovarian cancer cell lines and in a murine bioluminescent orthotopic surgical xenograft model for EOC.

Methods

The effects of panobinostat, both alone and in combination with carboplatin, on proliferation and apoptosis in ovarian cancer cell lines, were evaluated using colony and WST-1 assays, Hoechst staining and flow cytometry analysis. In addition, mechanisms were characterised by western blotting and phosphoflow analysis. Immuno-deficient mice were engrafted orthotopically with SKOV-3^luc+ cells and serial bioluminescence imaging monitored the effects of treatment with panobinostat and/or carboplatin and/or surgery. Survival parameters were also measured.

Results

Panobinostat treatment reduced cell growth and diminished cell viability, as shown by the induced cell cycle arrest and apoptosis in vitro. We observed increased levels of cleaved PARP and caspase-3, downregulation of cdc2 protein kinase, acetylation of H2B and higher pH2AX expression. The combined administration of carboplatin and panobinostat synergistically increased the anti-tumour effects compared to panobinostat or carboplatin treatment alone. In our novel ovarian cancer model, the mice showed significantly higher rates of survival when treated with panobinostat, carboplatin or a combination of both, compared to the controls. Panobinostat was as efficient as carboplatin regarding prolongation of survival. No significant additional effect on survival was observed when surgery was combined with carboplatin/panobinostat treatment.

Conclusions

Panobinostat demonstrates effective in vitro growth inhibition in ovarian cancer cells. The efficacy of panobinostat and carboplatin was equal in the orthotopic EOC model used. We conclude that panobinostat is a promising therapeutic alternative that needs to be further assessed for the treatment of EOC.

Outcomes of advanced epithelial ovarian cancer with integration of metronomic chemotherapy: An Indian rural cancer centre experience

BACKGROUND

Paclitaxel-platinum and optimal cytoreductive surgery are the standard of care for ovarian carcinoma. Poor socioeconomic profile and therapeutic constraints in rural India poses a therapeutic challenge.

AIM

To evaluate outcomes of epithelial ovarian carcinoma.

OBJECTIVES

To calculate disease-free survival (DFS), overall survival (OS), and factors affecting outcomes.

MATERIALS AND METHODS

Data of patients diagnosed as ovarian carcinoma registered between March 2009 and March 2014 were retrieved. Demographic profile, chemotherapy and response, surgery, and disease progression were collected. Patients who underwent surgery or completed three cycles of chemotherapy were selected. Kaplan-Meir survival was used to determine disease-free and OS. Log-rank test used to evaluate factors affecting outcome.

RESULTS

Median follow-up is 26 months. 93/102 patients (91%) underwent cytoreductive surgery, of which 37 had primary cytoreduction (40%) while 56 had interval cytoreduction. 21/93 (23%), 57/93 (61%), and 15/93 (16%) patients were operated by local surgeons, surgeons of our hospital, and trained oncosurgeons, respectively. Induction paclitaxel-platinum was used in 35/63 (56%) patients while 28/63 patients (44%) received neoadjuvant metronomic chemotherapy. Median DFS and OS are 17 and 54 months respectively while 3 year OS of 66%. Median DFS of patients operated by oncosurgeons versus local surgeons were 22 months versus 15 months (P = 0.01), OS was 54 versus 26 months (P = 0.01).40/88 (45%) patients received maintenance metronomic therapy after adjuvant chemotherapy with median of 6 months (range 2-18 months). Patients receiving metronomic maintenance had better DFS, 18 months versus 15 months (P = 0.69).

CONCLUSION

Induction therapy in ovarian carcinoma helps in selecting patients for cytoreductive surgery. Outcomes are better if operated by trained oncosurgeons. Maintenance metronomic has potential to delay disease progression.

Serum cytokeratin-19 fragment (Cyfra 21-1) is a prognostic indicator for epithelial ovarian cancer

OBJECTIVES

Cytokeratin 19 is significant for indicating cancer cells, and Cyfra 21-1 is a fragment of cytokeratin 19. This retrospective study was designed to define the prognostic value of serum Cyfra 21-1 in epithelial ovarian cancers (EOC).

MATERIALS AND METHODS

Serum Cyfra 21-1 concentration was obtained from 42 patients with EOC prior to treatment. Various prognostic aspects were examined using univariable and multivariable analyses. The standard serum marker cancer antigen 125 was measured simultaneously and compared in this analysis.

RESULTS

Serum levels of both Cyfra 21-1 and cancer antigen 125 were associated with positive retroperitoneal lymph nodes and platinum resistance; higher levels of Cyfra 21-1 (3.0 ng/mL as the cut-off) were associated with shorter disease-free survival (16 months vs. 28 months, p = 0.001) and overall survival (29 months vs. 41 months, p = 0.007) than lower levels. Further univariable analysis showed that Cyfra 21-1, poor differentiation, and retroperitoneal lymph node metastasis were related to platinum resistance and mortality. Multivariable analysis indicated retroperitoneal lymph node metastasis and serum Cyfra 21-1 were independent risk factors for both disease-free survival and overall survival.

CONCLUSION

The pretreatment level of serum Cyfra 21-1 had remarkable prognostic significance for EOC, indicating poor survival when it was elevated above 3.0 ng/mL.

MicroRNAs regulate several functions of normal tissues and malignancies

MicroRNAs (miRNAs, miRs) are a cluster of naturally occurring small non-coding RNA molecules of 19-24 nucleotides in length. miRs control gene expression post-transcriptionally by binding to a specific site at the 3'-UTR of target mRNA, which results in mRNA cleavage and translation repression. Nearly 1000 miRs in the human genome have been identified, and it is believed that these miRs contribute to at least 60% of the human transcriptome. Recent research has shown that miRs are emerging as important regulators of cellular differentiation and dedifferentiation. In addition, dysregulation of miR expression may play a fundamental role in the onset, progression and dissemination of cancers. In this review, we focus on some paradigms of miR involvement in tumorigenesis, such as ovarian cancer, and also discuss the relationship between miRs and cancer stem cells.

Effect of gonadotropin-releasing hormone agonist on ES-2 ovarian cancer cells

OBJECTIVE

Gonadotropin-releasing hormone (GnRH) receptor is found in the ovarian tissue, including epithelial ovarian cancer (EOC), suggesting that GnRH agonists may have direct action on EOC.

MATERIALS AND METHODS

Ovarian clear cell cancer (ES-2) cells were treated with low-dose GnRH agonist with/without low-dose paclitaxel (1 μM D-Lys(6) with/without 0.5 μM or 1.0 μM paclitaxel). Growth and behavior of ES-2 cells were evaluated.

RESULTS

Use of either D-Lys(6) or paclitaxel or a combination of the two did not affect the morphology and growth pattern of ES-2 cells. However, ability of migration and invasion of ES-2 cells was significantly decreased in either use of D-Lys(6) or paclitaxel and more apparent with the combination. Type I GnRH receptor expression of ES-2 was not altered significantly by the combination.

CONCLUSION

GnRH agonist might modify the ES-2 ovarian cancer cells, and its role might be independent, additional or synergistic, suggesting the potential role of the use of GnRH agonist in the management of clear cell type of the ovarian cancer. However, the results of this study were derived using ES-2 ovarian cancer cells, and might not be valid in other cell types of ovarian cancers.