Phase II study of gemcitabine and vinorelbine as second- or third-line therapy in patients with primary refractory or platinum-resistant recurrent ovarian and primary peritoneal cancer by the Korean Cancer Study Group (KCSG)_KCSG GY10-10

Prediction Model for Therapeutic Responses in Ovarian Cancer Patients using Paclitaxel-resistant Immune-related lncRNAs

BACKGROUND

Ovarian cancer (OC) is the deadliest malignant tumor in women with a poor prognosis due to drug resistance and lack of prediction tools for therapeutic responses to anti- cancer drugs.

OBJECTIVE

The objective of this study was to launch a prediction model for therapeutic responses in OC patients.

METHODS

The RNA-seq technique was used to identify differentially expressed paclitaxel (PTX)- resistant lncRNAs (DE-lncRNAs). The Cancer Genome Atlas (TCGA)-OV and ImmPort database were used to obtain immune-related lncRNAs (ir-lncRNAs). Univariate, multivariate, and LASSO Cox regression analyses were performed to construct the prediction model. Kaplan- meier plotter, Principal Component Analysis (PCA), nomogram, immune function analysis, and therapeutic response were applied with Genomics of Drug Sensitivity in Cancer (GDSC), CIBERSORT, and TCGA databases. The biological functions were evaluated in the CCLE database and OC cells.

RESULTS

The RNA-seq defined 186 DE-lncRNAs between PTX-resistant A2780-PTX and PTXsensitive A2780 cells. Through the analysis of the TCGA-OV database, 225 ir-lncRNAs were identified. Analyzing 186 DE-lncRNAs and 225 ir-lncRNAs using univariate, multivariate, and LASSO Cox regression analyses, 9 PTX-resistant immune-related lncRNAs (DEir-lncRNAs) acted as biomarkers were discovered as potential biomarkers in the prediction model. Single-cell RNA sequencing (scRNA-seq) data of OC confirmed the relevance of DEir-lncRNAs in immune responsiveness. Patients with a low prediction score had a promising prognosis, whereas patients with a high prediction score were more prone to evade immunotherapy and chemotherapy and had poor prognosis.

CONCLUSION

The novel prediction model with 9 DEir-lncRNAs is a valuable tool for predicting immunotherapeutic and chemotherapeutic responses and prognosis of patients with OC.

Nanoparticle delivery systems to combat drug resistance in ovarian cancer

Due to the lack of early symptoms and difficulty of accurate diagnosis, ovarian cancer is the most lethal gynecological cancer faced by women. First-line therapy includes a combination of tumor resection surgery and chemotherapy regimen. However, treatment becomes more complex upon recurrence due to development of drug resistance. Drug resistance has been linked to many mechanisms, including efflux transporters, apoptosis dysregulation, autophagy, cancer stem cells, epigenetics, and the epithelial-mesenchymal transition. Thus, developing and choosing effective therapies is exceptionally complex. There is a need for increased specificity and efficacy in therapies for drug-resistant ovarian cancer, and research in targeted nanoparticle delivery systems aims to fulfill this challenge. Although recent research has focused on targeted nanoparticle-based therapies, few of these therapies have been clinically translated. In this review, non-viral nanoparticle delivery systems developed to overcome drug-resistance in ovarian cancer were analyzed, including their structural components, surface modifications, and drug-resistance targeted mechanisms.

Cauda equina syndrome secondary to leptomeningeal metastases from recurrent primary peritoneal carcinoma

The patient is a 42-year-old woman with metastatic primary peritoneal carcinoma and known brain metastases, who subsequently developed cauda equina syndrome after presenting with ataxia, lower extremity weakness, and bowel and bladder incontinence secondary to leptomeningeal metastasis after treatment with neoadjuvant chemotherapy, surgical debulking, and adjuvant chemotherapy. Metastases to the central nervous system (CNS) and leptomeninges are rare events in epithelial ovarian and primary peritoneal carcinomas as these tumours do not have a predilection for the CNS. Cauda equina syndrome is often characterised by gait disturbances, bowel and bladder dysfunction, saddle anaesthesia, and lower extremity muscle weakness. In patients with known metastatic gynaecologic carcinomas presenting with nonspecific neurologic symptoms, cauda equina syndrome should remain high in the differential diagnosis.

Switching from standard to dose-dense chemotherapy in front-line treatment of advanced ovarian cancer: a retrospective study of feasibility and efficacy

BACKGROUND

Current standard neoadjuvant treatment for advanced ovarian cancer is 3-weekly platinum-based chemotherapy (CP3w). Patients unable to have interval debulking surgery (IDS) or with significant residual disease have a poor outcome to CP3w treatment. We investigated the outcome in patients who were switched to dose-dense chemotherapy.

METHODS

We retrospectively analysed 30 patients treated at UCLH in 2009-2013, who switched to dose-dense chemotherapy after neoadjuvant CP3w, having achieved a poor response/progressed and unable to proceed to IDS (n=21), or had >1 cm residual disease after IDS (n=9). Treatment was 3-weekly carboplatin and weekly paclitaxel (n=23), or both drugs weekly (n=7). For comparison, we included 30 matched patients treated with CP3w followed by IDS (n=24, without or ≤1 cm residual disease; n=6, with >1 cm residual disease). Time to progression (TTP) and overall survival (OS) were measured from the date of diagnosis until progression (CT scan or CA-125) and death from any cause, respectively.

RESULTS

Baseline characteristics were similar in both groups. The response rate to dose-dense chemotherapy was 70% (Gynecological Cancer Intergroup criteria). In the dose-dense group, 24 patients had tumour progression and 16 died; the corresponding numbers in the control group were 24 and 11. Median TTP was 15.8 months with dose-dense therapy, higher than expected for this patient group, and the same as in the control group (15.7 months) undergoing IDS, p=0.27. Median TTP in patients with residual disease postsurgery was 16.5 months (dose-dense) and 10.8 months (controls), p=0.02. TTP in dose-dense patients who did not have surgery was 10.4 months. Median OS was 31.3 (dose-dense) and 59.6 months (controls), p=0.06. Dose-dense chemotherapy was well tolerated: only three patients interrupted treatment due to toxicity.

CONCLUSION

Switching to dose-dense chemotherapy in patients who failed to respond to CT3w neoadjuvant chemotherapy appears to be an effective strategy and requires further investigation.