Clinical, Pathological and Prognostic Features of Rare BRAF Mutations in Metastatic Colorectal Cancer (mCRC): A Bi-Institutional Retrospective Analysis (REBUS Study)

Simple SummarySomatic BRAF mutations occur in approximately 10% of metastatic colorectal cancers (mCRCs) and, according to the involved codon, are classified as V600E and in non-V600, accounting for 80% and 20%, respectively. Being the most frequent mutation, the BRAF V600E mutation has been extensively investigated and up to now its clinical, pathological and molecular phenotype and its prognostic impact have been clearly described. On the contrary, evidence concerning BRAF non-V600 is weaker. We retrospectively evaluated 537 mCRC patients treated at two Italian Institutions. This study corroborates and strengthens available evidence concerning phenotype and prognostic performance of BRAF non-V600 compared to BRAF V600E and BRAF wild-type mCRCs. This deeper insight on rare BRAF non-V600 mutated mCRC is a primary issue in the precision oncology era, since the wider application of NGS is expected to increase the identification of those aberrations.Recently, retrospective analysis began to shed light on metastatic colorectal cancers (mCRCs) harboring rare BRAF non-V600 mutations, documenting a distinct phenotype and a favorable prognosis. This study aimed to confirm features and prognosis of rare BRAF non-V600 mCRCs compared to BRAF V600E and BRAF wild-type mCRCs treated at two Italian Institutions. Overall, 537 cases were retrospectively evaluated: 221 RAS/BRAF wild-type, 261 RAS mutated, 46 BRAF V600E and 9 BRAF non-V600. Compared to BRAF V600E mCRC, BRAF non-V600 mCRC were more frequently left-sided, had a lower tumor burden and displayed a lower grade and an MMR proficient/MSS status. In addition, non-V600 mCRC patients underwent more frequently to resection of metastases with radical intent. Median overall survival (mOS) was significantly longer in the non-V600 compared to the V600E group. At multivariate analysis, only age < 65 years and ECOG PS 0 were identified as independent predictors of better OS. BRAF V600E mCRCs showed a statistically significant worse mOS when compared to BRAF wild-type mCRCs, whereas no significant difference was observed between BRAF non-V600 and BRAF wild-type mCRCs. Our study corroborates available evidence concerning incidence, clinicopathologic characteristics and prognosis of BRAF-mutated mCRCs

Recent progress in the use of pharmacotherapy for endometrial cancer

Introduction Endometrial cancer (EC) is the most common gynecological cancer in developed countries. The ESGO/ESTRO/ESP updated evidence-based guidelines in 2020, introducing molecular classification to guide EC treatment. The genomic-based approach has identified four prognostic subgroups of EC. Each of these may benefit from a tailored treatment depending on the molecular profile, the histotype, and stage of disease for the adjuvant and the metastatic/recurrent setting. Several clinical trials are now ongoing to identify the best treatment according to the molecular profile of EC. Areas covered This review analyzes tailored treatment for EC according to the molecular profile, both in the adjuvant and in the metastatic/recurrent setting. The authors review the results of clinical studies and highlight ongoing trials. Expert opinion Several new agents are under evaluation in order to personalize EC treatment according to specific molecular profiles in the adjuvant, advanced, and recurrent settings. Clinical trials investigating the impact of molecular classification have yielded encouraging results. EC can no longer be considered a single tumor entity susceptible to a single treatment modality but rather be split into four distinct types, requiring tailored treatments

Advanced and recurrent endometrial cancer: State of the art and future perspectives

Patients with primary metastatic/recurrent endometrial cancer have poor prognosis and available therapeutic options are limited. Current treatment is mainly based on platinum-based chemotherapy. Recently, the Food and Drug Administration (FDA) granted approval for the combination of pembrolizumab and lenvatinib for endo-metrial cancer patients without microsatellite instability (MSS) progressing on a previous line of therapy while European Medicines Agency (EMA) approved the combination for all comers patients failing previous platinum treatment. Anti programmed cell death protein-1 (PD-1) dostarlimab (TSR-042) was approved as monotherapy in patients with advanced, microsatellite instable (MSI) endometrial cancer progressing to platinum treatment. Phase II-III clinical trials in metastatic endometrial cancer are mainly focused on target therapies and immu-notherapy as single agents or in combination. Unfortunately, most of these trials are lacking of predictive bio-markers of response to select patients most or at least likely to benefit from those treatments

PARP Inhibitors Resistance: Mechanisms and Perspectives

PolyADP-ribose polymerase (PARP) inhibitors (PARPis) represent the first clinically approved drugs able to provoke “synthetic lethality” in patients with homologous recombination-deficient (HRD) tumors. Four PARPis have just received approval for the treatment of several types of cancer. Besides, another three additional PARPis underlying the same mechanism of action are currently under investigation. Despite the success of these targeted agents, the increasing use of PARPis in clinical practice for the treatment of different tumors raised the issue of PARPis resistance, and the consequent disease relapse and dismal prognosis for patients. Several mechanisms of resistance have been investigated, and ongoing studies are currently focusing on strategies to address this challenge and overcome PARPis resistance. This review aims to analyze the mechanisms underlying PARPis resistance known today and discuss potential therapeutic strategies to overcome these processes of resistance in the future

Preclinical and Clinical Evidence of Lurbinectedin in Ovarian Cancer: Current Status and Future Perspectives

Lurbinectedin is an antitumor agent belonging to the natural marine-based tetrahydroisoquinoline family which has shown very promising clinical activity with a favorable safety profile in many types of cancer. Preclinical evidence showed that lurbinectedin inhibits active transcription and binds to GC-rich sequences, leading to irreversible degradation of RNA polymerase II and generation of single- and double-strand DNA breaks and, as a consequence, apoptosis of tumor cells. In addition, lurbinectedin has demonstrated modulation of the tumor microenvironment and activity against cancer cells harboring homologous recombination DNA repair deficiency. Although considerable improvements have been made in the treatment of epithelial ovarian cancer, most patients with advanced disease experience recurrence with a dismal prognosis due to chemotherapy (mainly platinum) resistance. Platinum-resistant/refractory ovarian cancer remains a difficult-to-treat setting of disease, and currently, the exploration of new therapeutic approaches represents a main field of interest. Although the CORAIL phase III study did not meet its primary endpoint, the results suggest that lurbinectedin might be a valid alternative for patients that have exhausted therapeutic options. This article will focus on the clinical evidence, the most recent investigations, and the future perspective regarding the use of lurbinectedin in ovarian cancer

Survival outcomes in patients with BRCA mutated, variant of unknown significance, and wild type ovarian cancer treated with PARP inhibitors

ObjectiveCorrelation between BRCA1/2 (BRCA) pathogenic variants and the response to poly (ADP-ribose) polymerase inhibitors (PARPi) has been recognized in patients with ovarian cancer. Moreover, data on the clinical implications of variants of unknown significance are lacking. The aim of this study was to evaluate differences in survival outcomes in patients with BRCA variants of unknown significance, mutated, and wild type relapsed ovarian cancer treated with PARPi. MethodsPatients with ovarian cancer whose somatic BRCA testing was available and who were receiving PARPi as maintenance treatment at the first recurrence between January 2014 and January 2021 were included in the present study and analyzed. Patients were divided into three groups according to BRCA mutational status (variant of unknown significance, mutated, and wild type). Progression-free survival was assessed in each study group. ResultsOf 67 patients identified, 20 (29.9%), 24 (35.8%), and 23 (34.3%) had BRCA variant of unknown significance, mutated, and wild type, respectively. Patients received PARPi as maintenance treatment at the time of the first relapse after a complete response or partial response to platinum-based chemotherapy without differences in the previous platinum-free interval among the analyzed groups. The median progression-free survival of patients with BRCA mutation was significantly longer than for those with BRCA wild type or variant of unknown significance (not reached vs 4 months vs 7 months, respectively; p<0.001). Additionally, no significant difference was found between patients with BRCA wild type and BRCA variant of unknown significance (p=0.50). ConclusionOur study suggests that carriers of BRCA variant of unknown significance have survival outcomes comparable to patients with BRCA wild type and shorter progression-free survival than women harboring BRCA pathogenic variants

Dual inhibition of CDK12 and CDK13 uncovers actionable vulnerabilities in patient-derived ovarian cancer organoids

Abstract Background High grade serous ovarian cancer (HGSOC) is highly lethal, partly due to chemotherapy resistance and limited availability of targeted approaches. Cyclin dependent kinases 12 and 13 (CDK12/13) are promising therapeutic targets in human cancers, including HGSOC. Nevertheless, the effects of their inhibition in HGSOC and the potential synergy with other drugs are poorly known. Methods We analyzed the effects of the CDK12/13 inhibitor THZ531 in HGSOC cells and patient-derived organoids (PDOs). RNA sequencing and quantitative PCR analyses were performed to identify the genome-wide effects of short-term CDK12/13 inhibition on the transcriptome of HGSOC cells. Viability assays with HGSOC cells and PDOs were performed to assess the efficacy of THZ531 as single agent or in combination with clinically relevant drugs. Results The CDK12 and CDK13 genes are deregulated in HGSOC and their concomitant up-regulation with the oncogene MYC predicts poor prognosis. HGSOC cells and PDOs display high sensitivity to CDK12/13 inhibition, which synergizes with drugs in clinical use for HGSOC. Transcriptome analyses revealed cancer-relevant genes whose expression is repressed by dual CDK12/13 inhibition through impaired splicing. Combined treatment with THZ531 and inhibitors of pathways regulated by these cancer relevant genes (EGFR, RPTOR, ATRIP) exerted synergic effects on HGSOC PDO viability. Conclusions CDK12 and CDK13 represent valuable therapeutic targets for HGSOC. We uncovered a wide spectrum of CDK12/13 targets as potential therapeutic vulnerabilities for HGSOC. Moreover, our study indicates that CDK12/13 inhibition enhances the efficacy of approved drugs that are already in use for HGSOC or other human cancers

Evaluation of Second-Line Anti-VEGF after First-Line Anti-EGFR Based Therapy in RAS Wild-Type Metastatic Colorectal Cancer: The Multicenter “SLAVE” Study

Background: The optimal anti-angiogenic strategy as second-line treatment in RAS wild-type metastatic colorectal cancer (mCRC) treated with anti-EGFR (Epidermal Growth Factor Receptor) based first-line treatment is still debated. Methods: This multicenter, real-world, retrospective study is aimed at evaluating the effectiveness of second-line Bevacizumab- and Aflibercept-based treatments after an anti-EGFR based first-line regimen. Clinical outcomes measured were: objective response rate (ORR), progression free survival (PFS), overall survival (OS) and adverse events (AEs) profiles. Results: From February 2011 to October 2019, 277 consecutive mCRC patients received Bevacizumab-based (228, 82.3%) or Aflibercept-based (49, 17.7%) regimen. No significant difference was found regarding ORR. The median follow-up was 27.7 months (95%CI: 24.7–34.4). Aflibercept-treated group had a significantly shorter PFS compared to Bevacizumab-treated group (5.6 vs. 7.1 months, respectively) (HR = 1.34 (95%CI: 0.95–1.89); p = 0.0932). The median OS of the Bevacizumab-treated group and Aflibercept-treated group was 16.2 (95%CI: 15.3–18.1) and 12.7 (95%CI: 8.8–17.5) months, respectively (HR= 1.31 (95%CI: 0.89–1.93) p = 0.16). After adjusting for the key covariates (age, gender, performance status, number of metastatic sites and primary tumor side) Bevacizumab-based regimens revealed to be significantly related with a prolonged PFS (HR = 1.44 (95%CI: 1.02–2.03); p = 0.0399) compared to Aflibercept-based regimens, but not with a prolonged OS (HR = 1.47 (95%CI: 0.99–2.17); p = 0.0503). The incidence of G3/G4 VEGF inhibitors class-specific AEs was 7.5% and 26.5% in the Bevacizumab-treated group and the Aflibercept-treated group, respectively (p = 0.0001). Conclusion: Our analysis seems to reveal that Bevacizumab-based regimens have a slightly better PFS and class-specific AEs profile compared to Aflibercept-based regimen as second-line treatment of RAS wild-type mCRC patients previously treated with anti-EGFR based treatments. These results have to be taken with caution and no conclusive considerations are allowed