BYL719

Targeting cell cycle regulation in colorectal cancer has not been fully evaluated. We investigated the efficacy of the CDK4/6 inhibitor, abemaciclib, and confirmed a synergistic interaction for PI3K p110α and CDK dual inhibition in colorectal cancer cell lines. Caco-2 and SNU-C4 cell lines were selected to explore the mechanism of action for and resistance to abemaciclib. In vitro and in vivo models were used to validate the anti-tumor activity of abemaciclib monotherapy and BYL719 combination therapy. Abemaciclib monotherapy inhibited cell cycle progression and proliferation in Caco-2 and SNU-C4 cells...

BACKGROUND: Combined targeting of CDK4/6 and ER is now the standard of care for patients with advanced ER+/HER2- breast cancer. However, acquired resistance to these therapies frequently leads to disease progression. As such, it is critical to identify the mechanisms by which resistance to CDK4/6-based therapies is acquired and also identify therapeutic strategies to overcome resistance. METHODS: In this study, we developed and characterized multiple in vitro and in vivo models of acquired resistance to CDK4/6-based therapies...

PURPOSE OF REVIEW: Over the past decade many previously poorly understood vascular malformation disorders have been linked to somatic activating mutations in PIK3CA, which regulates cell survival and growth via activation of the mTOR1-AKT pathway. The goal of this article is to describe and provide an update on the clinical features, complications, and management strategies for the PIK3CA-related overgrowth spectrum (PROS). RECENT FINDINGS: PROS encompasses a heterogenous group of disorders with complications related to the tissues harboring the mutation...

Macrodactyly is a disabling congenital disease characterized by overgrowth of soft tissues and bones, which leads to finger enlargement and joint deformity. The mechanism of bone overgrowth in macrodactyly was rarely understood. In our study bone manifestations of three macrodactyly patients were analyzed by micro-CT. PIK3CA mutation was detected by next-generation sequencing (NGS) of a tumor gene-panel. The PI3K/AKT/mTOR pathway activation and target genes were analyzed. The osteogenic potential of macrodactyly-derived bone marrow mesenchymal stem cells (MAC-BMSCs) was compared with polydactyly-derived bone marrow mesenchymal stem cells (PD-BMSCs)...

PURPOSE: Rash develops in approximately 50% of patients receiving alpelisib for breast cancer, often requiring dose modifications. Here, we describe the clinicopathologic, laboratory, and management characteristics of alpelisib-related dermatologic adverse events (dAEs). METHODS: A single center-retrospective analysis was conducted. Data were abstracted from electronic medical records. RESULTS: A total of 102 patients (mean age 56 years, range 27-83) receiving alpelisib most frequently in combination with endocrine therapy (79, 77...

Oral cavity squamous cell carcinomas (OSCCs) are aggressive tumors, and their recurrence leads to poor prognosis and reduced survival rates. This study aimed to identify therapeutic targets and to evaluate the efficacy of targeted inhibitors in OSCC patient-derived xenograft (PDX) models. Herein, we reported that OSCC PDXs recapitulated the genomic signatures of their paired primary tumors and the expression of CHEK1 , PIK3CA , and PIK3CD was significantly upregulated in OSCC. The antitumor efficacy of CHK1 inhibitors (PF477736, AZD7762, LY2606368) and PI3K inhibitors (BYL719, GDC0941, GSK1059615) was investigated in OSCC cell lines and PDX models...

Targeting the epigenome of cancer cells with the combination of Bromodomain and Extra Terminal (BET) protein inhibitors and histone deacetylase (HDAC) inhibitors has shown synergistic antitumor effects in several cancer types. In this study, we investigate the antitumor potential of the novel dual BET/HDAC inhibitor TW09 in rhabdomyosarcoma (RMS) cells. TW09 reduces cell viability, suppresses long-term clonogenic survival and induces cell death in RMS cells in a dose-dependent manner. Compared to BET/HDAC co-inhibition using JQ1 and MS-275, TW09 induces similar cell death at equimolar concentrations and regulates BET and HDAC target proteins (e...

Phosphatidylinositol 3-kinase alpha (PI3Kα) is among the most important PI3K isoforms and has been associated with multiple human cancers. Therefore, PI3Kα has garnered considerable attention as a viable target for anticancer drug discovery, and thus the identification and development of highly potent inhibitors of this isoform has become an important line of research. Here, structure-based virtual screening, bioassays, and molecular dynamics simulations were performed to discover novel potential PI3Kα inhibitors...

PURPOSE: The PI3K/AKT/mTOR pathway is one of the most highly activated cellular signaling pathways in advanced ovarian cancer. Although several PI3K/AKT/mTOR inhibitors have been developed to treat various types of cancer, the antitumor efficacy of many of these compounds against ovarian cancer has remained unclear. METHODS: Here, we tested and compared a panel of 16 PI3K/AKT/mTOR inhibitors (XL765, Miltefosine, Rapamycin, CCI-779, RAD001, FK506, XL147, GSK2110183, IPI-145, GSK2141795, BYL719, GSK458, CAL-101, XL765 analogue SAR245409, Triciribine, and GDC0941) that have entered clinical trials for antitumor activity against ovarian cancer, as well as the front line drug, paclitaxel...

Capillary lymphatic venous malformations (CLVM) are complex vascular anomalies characterized by aberrant and enlarged lymphatic and blood vessels. CLVM appear during fetal development and enlarge after birth, causing life-long complications such as coagulopathy, pulmonary embolism, chronic pain, and disfigurement. Treatment includes surgical debulking, amputation, and recurrent sclerotherapy. Somatic, mosaic mutations in the 110-kD catalytic α-subunit of phosphoinositide-3-kinase (PIK3CA) gene have been previously identified in affected tissues from CLVM patients; however, the cell population harboring the mutation is still unknown...

BACKGROUND: BRCA1/2 germline mutation related cancers are candidates for new immune therapeutic interventions. This study was a hypothesis generating exploration of genomic data collected at diagnosis for 19 patients. The prominent tumor mutation burden (TMB) in hereditary breast and ovarian cancers in this cohort was not correlated with high global immune activity in their microenvironments. More information is needed about the relationship between genomic instability, phenotypes and immune microenvironments of these hereditary tumors in order to find appropriate markers of immune activity and the most effective anticancer immune strategies...

Remodeling transcription by targeting bromodomain and extraterminal (BET) proteins has emerged as promising anticancer strategy. Here, we identify a novel synergistic interaction of the BET inhibitor JQ1 with the PI3Kα-specific inhibitor BYL719 to trigger mitochondrial apoptosis and to suppress tumor growth in models of rhabdomyosarcoma (RMS). RNA-Seq revealed that JQ1/BYL719 co-treatment shifts the overall balance of BCL-2 family gene expression towards apoptosis and upregulates expression of BMF, BCL2L11 (BIM), and PMAIP1 (NOXA) while downregulating BCL2L1 (BCL-xL )...

The phosphoinositide 3-kinase (PI3K) signaling pathway is frequently mutated in head and neck squamous cell carcinoma (HNSCC), often via gain-of-function (GOF) mutations in the PIK3CA gene. Here we present novel genetically-engineered mouse models (GEMM) carrying a GOF allele Loxp-STOP-Loxp(LSL)-PIK3CAH1047R (E20) alone or in combination with heterozygous LSL-p53+/R172H (p53) mutation with tissue-specific expression to interrogate the role of oncogenic PIK3CA in transformation of upper aerodigestive track epithelium...

BACKGROUND: Mutation of TP53 gene is a hallmark of head and neck squamous cell carcinoma (HNSCC) not yet exploited therapeutically. TP53 mutation frequently leads to the synthesis of mutant p53 proteins with gain-of-function activity, associated with radioresistance and high incidence of local recurrences in HNSCC. METHODS: mutant p53-associated functions were investigated through Gene Set Enrichment Analysis in the TCGA cohort of HNSCC and in a panel of 22 HNSCC cell lines...

BACKGROUND/AIM: Medulloblastoma (MB) accounts for ~20% of pediatric malignant central nervous system tumors. Treatment strategies, including surgery, radiation therapy and/or chemotherapy, are effective, but recurrence and metastasis frequently occur. Therefore, novel therapies are required. Herein, the effects of fibroblast growth factor receptor (FGFR) and phosphoinositide 3-kinase (PI3K) inhibitors on MB cells lines were evaluated. MATERIALS AND METHODS: MB cell lines (UW228-3, DAOY, Med8a, D425, D283) were tested for sensitivity to FGFR (AZD4547) and PI3K (BEZ235 and BYL719) inhibitors by viability, cytotoxicity, apoptosis, and proliferation assays...

PURPOSE: Activation of the PI3K/mTOR signaling pathway is common in head and neck squamous cell carcinoma (HNSCC). BYL719 is an α-specific PI3K inhibitor that is synergistic and efficacious when combined with cetuximab, a Food and Drug Administration-approved radiosensitizing agent in the treatment of HNSCC. The agent independently has been shown to enhance radiosensitivity. This study evaluates the addition of BYL719 to cetuximab and radiation in the treatment of locally advanced HNSCC...

Poly(ADP‑ribose) polymerase (PARP) inhibitors have little effect on homologous recombination repair (HRR)‑proficient tumor types, such as cervical cancer. In addition to catalytic activity, the PARP inhibitor, BMN673, traps PARP1 on damaged DNA and induces cytotoxic effects. The aim of the present study was to evaluate the therapeutic effect of PI3K inhibitors and BMN673 on cervical cancer cells. The Chou‑Talalay method was used to assess the synergistic effect of drug combinations on cervical cancer cells...

Heterotopic ossification (HO) is the pathological formation of ectopic endochondral bone within soft tissues. HO occurs following mechanical trauma, burns, or congenitally in patients suffering from fibrodysplasia ossificans progressiva (FOP). FOP patients carry a conserved mutation in ACVR1 that becomes neomorphic for activin A responses. Here, we demonstrate the efficacy of BYL719, a PI3Kα inhibitor, in preventing HO in mice. We found that PI3Kα inhibitors reduce SMAD, AKT, and mTOR/S6K activities. Inhibition of PI3Kα also impairs skeletogenic responsiveness to BMPs and the acquired response to activin A of the Acvr1R206H allele...

Background : The phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway is hyperactivated in lung cancer and regulates a broad range of cellular processes, including proliferation, survival, angiogenesis, and metastasis. Thus PI3K is considered a promising target for therapy. To date, PI3K inhibitors have not been approved for lung cancer. Recent studies showed that the antipsychotic agent flupentixol induced apoptosis of lung cancer cell, however the anti-tumor mechanism of flupentixol remains unclear...

There are no officially approved therapies for metastatic pheochromocytomas apart from ultratrace 131I-MIBG therapy approved only in the United States. We have, therefore, investigated the anti-tumor potential of novel molecular-targeted approaches in murine pheochromocytoma cell lines (MPC/MTT), immortalized mouse chromaffin Sdhb-/- cells, 3D-pheochromocytoma tumor models (MPC/MTT spheroids) and human pheochromocytoma primary cultures. We identified the specific PI3Kα inhibitor BYL719 and the mTORC1 inhibitor everolimus as the most effective combination in all models...