Spotlight on New Hallmarks of Drug-Resistance towards Personalized Care for Epithelial Ovarian Cancer.

Epithelial ovarian cancer (EOC) is the deadliest gynecological malignancy worldwide. Despite the latest advances, a major clinical issue in EOC is the disappointing prognosis related to chemoresistance in almost one-third of cases. Drug resistance relies on heterogeneous cancer stem cells (CSCs), endowed with tumor-initiating potential, leading to relapse. No biomarkers of chemoresistance have been validated yet. Recently, major signaling pathways, micro ribonucleic acids (miRNAs), and circulating tumor cells (CTCs) have been advocated as putative biomarkers and potential therapeutic targets for drug resistance. However, further investigation is mandatory before their routine implementation. In accordance with the increasing rate of therapeutic efforts in EOC, the need for biomarker-driven personalized therapies is growing. This review aims to discuss the emerging hallmarks of drug resistance with an in-depth insight into the underlying molecular mechanisms lacking so far. Finally, a glimpse of novel therapeutic avenues and future challenges will be provided.

Optimizing CDK4/6 inhibitors in advanced HR+/HER2- breast cancer: A personalized approach.

Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) combined with endocrine therapy (ET) are now a backbone of treatment for hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. CDK4/6i plus ET is more effective than ET alone in this setting; however, the risk of grade 3-4 adverse events also increases. Approved agents in this class have similar efficacies, but important differences due to their structural and pharmacological properties. We review biomarkers and discuss determinants to inform a rational approach to therapy choice when selecting the most appropriate ET and CDK4/6i partners. We also identify subgroups that may benefit from specific ET-CDK4/6i combinations and discuss strategies to overcome resistance. This personalized approach aims to minimize treatment-related toxicities that may affect patient QoL and compliance, and ultimately therapy efficacy.

Thromboembolic events and antithrombotic prophylaxis in advanced ovarian cancer patients treated with bevacizumab: secondary analysis of the phase IV MITO-16A/MaNGO-OV2A trial.

INTRODUCTION: The use of routine antithrombotic prophylaxis is not recommended for advanced cancer patients receiving chemotherapy. The effect of bevacizumab-containing therapy on the risk of thromboembolic events remains controversial in ovarian cancer patients. We report on the incidence of thromboembolic events and the prevalence of antithrombotic therapy in patients enrolled in the single arm, phase IV, MITO-16A/MaNGO-OV2A trial. METHODS: In this trial, potential prognostic factors for patients with previously untreated ovarian cancer receiving a combination of platinum-based chemotherapy and bevacizumab were explored and the final analysis has already been reported. In this secondary analysis, the occurrence of thromboembolic events and the use of antithrombotic therapy were described according to the clinical characteristics of the patients. The prognostic role of thromboembolic events for progression-free and overall survival were also evaluated. RESULTS: From October 2012 to November 2014, 398 eligible patients were enrolled. 76 patients (19.1%) were receiving some type of anticoagulant or anti-aggregant treatment at baseline. Overall, 24 thromboembolic events were reported (cumulative incidence of 6.0%). The occurrence of thromboembolic events was not associated with baseline patient characteristics and was not modified by the use of antithrombotic prophylaxis (HR 0.60, 95% CI 0.18 to 2.0). Occurrence of thromboembolic events was not associated with progression-free survival (HR 1.34, 95% CI 0.83 to 2.15) or overall survival (HR 0.78, 95% CI 0.37 to 1.61). CONCLUSIONS: In our study, a 6.0% rate of thromboembolic events was reported during treatment with bevacizumab plus chemotherapy. Thromboembolic events were not associated with the clinical characteristics of the patients or with the use of antithrombotic prophylaxis, nor did they significantly affect the long-term prognosis. TRIAL REGISTRATION NUMBER: NCT01706120.

Bevacizumab, carboplatin, and paclitaxel in the first line treatment of advanced ovarian cancer patients: the phase IV MITO-16A/MaNGO-OV2A study.

OBJECTIVE: To explore the clinical and biological prognostic factors for advanced ovarian cancer patients receiving first-line treatment with carboplatin, paclitaxel, and bevacizumab. METHODS: A multicenter, phase IV, single arm trial was performed. Patients with advanced (FIGO (International Federation of Gynecology and Obstetrics) stage IIIB-IV) or recurrent, previously untreated, ovarian cancer received carboplatin (AUC (area under the curve) 5), paclitaxel (175 mg/m2) plus bevacizumab (15 mg/kg) on day 1 for six 3-weekly cycles followed by bevacizumab single agent (15 mg/kg) until progression or unacceptable toxicity up to a maximum of 22 total cycles. Here we report the final analysis on the role of clinical prognostic factors. The study had 80% power with a two-tailed 0.01 α error to detect a 0.60 hazard ratio with a factor expressed in at least 20% of the population. Both progression-free and overall survival were used as endpoints. RESULTS: From October 2012 to November 2014, 398 eligible patients were treated. After a median follow-up of 32.3 months (IQR 24.1-40.4), median progression-free survival was 20.8 months (95% CI 19.1 to 22.0) and median overall survival was 41.1 months (95% CI 39.1 to 43.5). Clinical factors significantly predicting progression-free and overall survival were performance status, stage, and residual disease after primary surgery. Neither baseline blood pressure/antihypertensive treatment nor the development of hypertension during bevacizumab were prognostic. There were two deaths possibly related to treatment, but no unexpected safety signal was reported. CONCLUSIONS: Efficacy and safety of bevacizumab in combination with carboplatin and paclitaxel and as maintenance were comparable to previous data. Hypertension, either at baseline or developed during treatment, was not prognostic. Performance status, stage, and residual disease after primary surgery remain the most important clinical prognostic factors. TRIAL REGISTRATION NUMBER: EudraCT 2012-003043-29; NCT01706120.

Carboplatin-based doublet plus bevacizumab beyond progression versus carboplatin-based doublet alone in patients with platinum-sensitive ovarian cancer: a randomised, phase 3 trial.

BACKGROUND: Bevacizumab is approved in combination with chemotherapy for the treatment of ovarian cancer, either in first-line therapy or for patients with recurrent disease not previously treated with the same drug. We aimed to test the value of continuing bevacizumab beyond progression after first-line treatment with the same drug. METHODS: In our open-label, randomised, phase 3 trial done at 82 sites in four countries, we enrolled women (aged ≥18 years) who had previously received first-line platinum-based therapy including bevacizumab, and had recurrent (≥6 months since last platinum dose), International Federation of Gynaecology and Obstetrics stage IIIB-IV ovarian cancer with an Eastern Cooperative Oncology Group performance status 0-2. Patients were randomly assigned (1:1) to receive a carboplatin-based doublet intravenously (carboplatin area under the concentration curve [AUC] 5 on day 1 plus paclitaxel 175 mg/m2 on day 1, every 21 days; carboplatin AUC 4 on day 1 plus gemcitabine 1000 mg/m2 on days 1 and 8, every 21 days; or carboplatin AUC 5 on day 1 plus pegylated liposomal doxorubicin 30 mg/m2 on day 1, every 28 days), or a carboplatin-based doublet plus bevacizumab (10 mg/kg intravenous every 14 days combined with pegylated liposomal doxorubicin-carboplatin, or 15 mg/kg every 21 days combined with gemcitabine-carboplatin or paclitaxel-carboplatin). Evaluable disease according to RECIST 1.1 guidelines was required before randomisation. Randomisation was done through the trial website with a minimisation procedure, stratified by centre, time of recurrence, performance status, and type of second-line chemotherapy. The primary endpoint was investigator-assessed progression-free survival, analysed on an intention-to-treat basis. Safety was assessed in all participants who received at least one dose. This trial is registered with ClinicalTrials.gov, NCT01802749 and EudraCT 2012-004362-17. FINDINGS: Between Dec 6, 2013, and Nov 11, 2016, 406 patients were recruited (203 [50%] assigned to the bevacizumab group and 203 [50%] to the standard chemotherapy group). 130 patients (64%) in the bevacizumab group and 131 (65%) in the standard chemotherapy group had progressed after receiving a last dose of platinum more than 12 months before, and 146 patients (72%) in the bevacizumab group and 147 (72%) in the standard chemotherapy group had progressed after completion of first-line bevacizumab maintenance. 161 participants (79%) progressed in the standard chemotherapy group, as did 143 (70%) in the bevacizumab group. Median progression-free survival was 8·8 months (95% CI 8·4-9·3) in the standard chemotherapy group and 11·8 months (10·8-12·9) in the bevacizumab group (hazard ratio 0·51, 95% CI 0·41-0·65; log-rank p<0·0001). Most common grade 3-4 adverse events were hypertension (20 [10%] in the standard chemotherapy group vs 58 (29%) in the bevacizumab group), neutrophil count decrease (81 [41%] vs 80 [40%]), and platelet count decrease (43 [22%] vs 61 [30%]). 68 patients (33%) died in the standard chemotherapy group and 79 (39%) died in the bevacizumab group; two deaths (1%) in the standard chemotherapy group and one death (<1%) in the bevacizumab group were deemed to be treatment-related. INTERPRETATION: Continuing bevacizumab beyond progression combined with chemotherapy in patients with platinum-sensitive recurrent ovarian cancer improves progression-free survival compared with standard chemotherapy alone and might be considered in clinical practice. FUNDING: Hoffmann-La Roche and Associazione Italiana per la Ricerca sul Cancro.

Comparison of the Genomic Profile of Cancer Stem Cells and Their Non-Stem Counterpart: The Case of Ovarian Cancer.

The classical cancer stem cell (CSC) model places CSCs at the apex of a hierarchical scale, suggesting different genetic alterations in non-CSCs compared to CSCs, since an ill-defined number of cell generations and time intervals separate CSCs from the more differentiated cancer cells that form the bulk of the tumor. Another model, however, poses that CSCs should be considered a functional state of tumor cells, hence sharing the same genetic alterations. Here, we review the existing literature on the genetic landscape of CSCs in various tumor types and as a case study investigate the genomic complexity of DNA obtained from matched CSCs and non-CSCs from five ovarian cancer patients, using a genome-wide single-nucleotide polymorphism (SNP) microarray.

Use of scalp cooling device to prevent alopecia for early breast cancer patients receiving chemotherapy: A prospective study.

Chemotherapy-induced alopecia (CIA) affects the majority of patients receiving chemotherapy (CT) for early breast cancer. It is a highly distressing side effect of CT, with psychological and social impact. Primary aim of the present analysis was to assess the efficacy of scalp cooling with DigniCap® in preventing CIA. Success rate was defined as patients' self-reported hair loss <50% according to Dean scale. In this analysis, we reported success rate at 3 weeks after the first CT course and at 3 weeks after the last CT course. Secondary endpoints included self-reported tolerability and patients' judgment on scalp cooling performance. Consecutive early breast cancer patients admitted to Istituto Oncologico Veneto who were recommended to receive neoadjuvant or adjuvant CT, were eligible to undergo scalp cooling during the CT administration within this study. 135 patients were included: 74% received adjuvant CT and 26% neoadjuvant CT (P < .001). The type of CT was: docetaxel-cyclophosphamide (26%), paclitaxel (23%), epirubicin-cyclophosphamide followed by paclitaxel (32%), and paclitaxel followed by epirubicincyclophosphamide (19%). The rate of success in preventing alopecia was 77% (104/135) at 3 weeks from the start of CT and 60% (81/135) at 3 weeks from the end of treatment. Higher success rates were reported in non-anthracycline (71%) compared to anthracycline-containing CT regimens (54%; P < 0.001). Premature discontinuation of scalp cooling was reported in 29/135 patients (21.5%), including withdrawal for alopecia (16/29), for low scalp cooling tolerability (8/29) or both (5/29). Scalp cooling was generally well tolerated. These results overall suggest that the use of scalp cooling is effective in preventing alopecia in the majority of early breast cancer patients receiving neoadjuvant or adjuvant CT, especially for patients undergoing a taxane-based non-anthracycline regimen.

Multicenter, randomised, open-label, non-comparative phase 2 trial on the efficacy and safety of the combination of bevacizumab and trabectedin with or without carboplatin in women with partially platinum-sensitive recurrent ovarian cancer.

BACKGROUND: Trabectedin, in addition to its antiproliferative effect, can modify the tumour microenvironment and this could be synergistic with bevacizumab. The efficacy and safety of trabectedin and bevacizumab ± carboplatin have never been investigated. METHODS: In this phase 2 study, women progressing between 6 and 12 months since their last platinum-based therapy were randomised to Arm BT: bevacizumab, trabectedin every 21 days, or Arm BT+C: bevacizumab, trabectedin and carboplatin every 28 days, from cycles 1 to 6, then trabectedin and bevacizumab as in Arm BT. Primary endpoints were progression-free survival rate (PFS-6) and severe toxicity rate (ST-6) at 6 months, assuming a PFS-6 ≤35% for BT and ≤40% for BT+C as not of therapeutic interest and, for both arms, a ST-6 ≥ 30% as unacceptable. RESULTS: BT+C (21 patients) did not meet the safety criteria for the second stage (ST-6 45%; 95%CI: 23%-69%) but PFS-6 was 85% (95%CI: 62%-97%). BT (50 patients) had 75% PFS-6 (95%CI: 60%-87%) and 16% ST-6 (95%CI 7%-30%). CONCLUSIONS: BT compared favourably with other platinum- and non-platinum-based regimens. The combination with carboplatin needs to be assessed further in a re-modulated safer schedule to confirm its apparent strong activity. CLINICAL TRIAL REGISTRATION: NCT01735071 (Clinicaltrials.gov).

Androgen Receptor Expression and Association With Distant Disease-Free Survival in Triple Negative Breast Cancer: Analysis of 263 Patients Treated With Standard Therapy for Stage I-III Disease.

Background: We evaluated immunohistochemical AR expression and correlation with prognosis in a large series of homogeneously treated patients with primary TNBC. Material and Methods: Patients diagnosed with stage I-III TNBC between 2000 and 2015 at Istituto Oncologico Veneto who received treatment with surgery and neoadjuvant and/or adjuvant chemotherapy were included. Whole tissue slides were stained for AR. AR-positive expression was defined as >1% of positively stained tumor cells. Distant-disease-free survival (DDFS) was calculated from diagnosis to distant relapse or death. Late-DDFS was calculated from the landmark of 3 years after diagnosis until distant relapse or death. Results: We included 263 primary TNBC patients. Mean AR expression was 14% (range 0-100%), and 29.7% (n = 78) of patients were AR+. AR+ vs. AR- cases presented more frequently older age (p < 0.001), non-ductal histology (p < 0.001), G1-G2 (p = 0.003), lower Ki67 (p < 0.001) and lower TILs (p = 0.008). At a median follow up of 81 months, 23.6% of patients experienced a DDFS event: 33.3% of AR+ and 19.5% of AR- patients (p = 0.015). 5 years DDFS rates were 67.2% and 80.6% for AR+ and AR- patients (HR = 1.82 95%CI 1.10-3.02, p = 0.020). AR maintained an independent prognostic role beyond stage, but when TILs were added to the model only stage and TILs were independent prognostic factors. AR was the only factor significantly associated with late-DDFS: 16.4% of AR+ and 3.4% of AR- patients experienced a DDFS after the landmark of 3 years after diagnosis (p = 0.001). Late-DDFS rates at 5 years from the 3-year landmark were 75.8% for AR+ and 95.2% for AR- patients (log-rank p < 0.001; HR = 5.67, 95%CI 1.90-16.94, p = 0.002). Conclusions: AR expression is associated with worse outcome for patients with TNBC. In particular, AR+ TNBC patients are at increased risk of late DDFS events. These results reinforce the rationale of AR targeting in AR+ TNBC.

A juxtacrine/paracrine loop between C-Kit and stem cell factor promotes cancer stem cell survival in epithelial ovarian cancer.

Receptors tyrosine kinase (RTK) enable normal and tumor cells to perceive and adapt to stimuli present in the microenvironment. These stimuli, also known as growth factors, are important molecular cues actively supporting cancer stem cell (CSC) self-renewal and viability. Since in epithelial ovarian cancer (EOC) the expression of c-Kit (CD117) has been identified as a CSC hallmark, we investigated the existence of a tumor growth-promoting loop between c-Kit and its ligand Stem Cell Factor (SCF). SCF exists as a soluble or transmembrane protein and through c-Kit interaction regulates cell viability, proliferation, and differentiation both in physiological and pathological conditions. High amounts of SCF were found in the ascitic effusions collected from EOC patients. While tumor cells and CSC only expressed the membrane-associated SCF isoform, both secreted and membrane-bound isoforms were expressed by tumor-associated macrophages (TAM, here shown to be M2-like) and fibroblasts (TAF). Circulating monocytes from EOC-bearing patients and healthy donors did not express both SCF isoforms. However, monocytes isolated from healthy donors produced SCF upon in vitro differentiation into macrophages, irrespectively of M1 or M2 polarization. In vitro, both SCF isoforms were able to activate the Akt pathway in c-Kit+ cells, and this effect was counteracted by the tyrosine kinase inhibitor imatinib. In addition, our results indicated that SCF could help c-Kit+ CSC survival in selective culture conditions and promote their canonical stemness properties, thus indicating the possible existence of a juxtacrine/paracrine circuit in EOC.

Autophagy inhibition reduces chemoresistance and tumorigenic potential of human ovarian cancer stem cells.

Epithelial ovarian cancer (EOC) is one of the most malignant gynecological tumors with a high mortality rate owing to tumor relapse after anticancer therapies. It is widely accepted that a rare tumor cell population, known as cancer stem cells (CSC), is responsible for tumor progression and relapse; intriguingly, these cells are able to survive nutrient starvation (such as in vitro culture in the absence of glucose) and chemotherapy treatment. Recent data also indicated that chemotherapy resistance is associated with autophagy activation. We thus decided to investigate both in vitro and in vivo the autophagic activity and the effects of the perturbation of this pathway in CSC isolated from EOC ascitic effusions. Ovarian CSC, identified according to their CD44/CD117 co-expression, presented a higher basal autophagy compared with the non-stem counterpart. Inhibition of this pathway, by in vitro chloroquine treatment or CRISPR/Cas9 ATG5 knockout, impaired canonical CSC properties, such as viability, the ability to form spheroidal structures in vitro, and in vivo tumorigenic potential. In addition, autophagy inhibition showed a synergistic effect with carboplatin administration on both in vitro CSC properties and in vivo tumorigenic activity. On the whole, these results indicate that the autophagy process has a key role in CSC maintenance; inhibition of this pathway in combination with other chemotherapeutic approaches could represent a novel effective strategy to overcome drug resistance and tumor recurrence.