BH3 mimetics targeting BCL-XL have efficacy in solid tumors with RB1 loss and replication stress.

BH3 mimetic drugs that inhibit BCL-2, BCL-XL, or MCL-1 have limited activity in solid tumors. Through assessment of xenograft-derived 3D prostate cancer models and cell lines we find that tumors with RB1 loss are sensitive to BCL-XL inhibition. In parallel, drug screening demonstrates that disruption of nucleotide pools by agents including thymidylate synthase inhibitors sensitizes to BCL-XL inhibition, together indicating that replication stress increases dependence on BCL-XL.

Time Toxicity Experienced by Early-Phase Cancer Clinical Trial Participants.

Purpose: Early-phase clinical trials (EP-CTs) are designed to determine optimal dosing, tolerability, and preliminary activity of novel cancer therapeutics. Little is known about the time that patients spend interacting with the health care system (eg, time toxicity) while participating in these studies.

Methods: We retrospectively reviewed the electronic health records of consecutive patients enrolled in EP-CTs from 2017 to 2019 to obtain baseline characteristics and number of health care-associated days, defined as all inpatient and outpatient visits while on trial.

Allosteric PI3Kα Inhibition Overcomes On-target Resistance to Orthosteric Inhibitors Mediated by Secondary PIK3CA Mutations.

Unlabelled: PIK3CA mutations occur in ∼8% of cancers, including ∼40% of HR-positive breast cancers, where the PI3K-alpha (PI3Kα)-selective inhibitor alpelisib is FDA approved in combination with fulvestrant. Although prior studies have identified resistance mechanisms, such as PTEN loss, clinically acquired resistance to PI3Kα inhibitors remains poorly understood. Through serial liquid biopsies and rapid autopsies in 39 patients with advanced breast cancer developing acquired resistance to PI3Kα inhibitors, we observe that 50% of patients acquire genomic alterations within the PI3K pathway, including PTEN loss and activating AKT1 mutations.

A Rare Presentation of Aggressive Renal Cell Carcinoma and the Utility of Early Molecular Testing in Rapidly Progressing Malignancies: A Case Report.

In rapidly progressing cancers, appropriate selection of first-line therapy is essential in prolonging survival. Alongside immunohistochemistry (IHC), comprehensive genomics, including whole exome and transcriptome sequencing (WES/WTS), can improve diagnostic accuracy and guide therapeutic management. Here, we report a young patient with rapidly progressing malignancy and unexpected post-mortem results, a scenario that may have been altered by early, comprehensive genomic sequencing.