Germline stem cell proliferation in requires activation of the GLP-1/Notch receptor, which is located on the germline plasma membrane and encoded by the gene. We previously identified several genes whose products directly or indirectly promote activity of the GLP-1 signaling pathway by finding mutations that enhance the germline phenotype of a allele, . Here, we report phenotypic and molecular analysis of a new allele, , that enhances the phenotype.
View Article and Find Full Text PDFPurpose: GDC-0810 (ARN-810) is a novel, non-steroidal, orally bioavailable, selective estrogen receptor degrader (SERD) that potentially inhibits ligand-dependent and ligand-independent estrogen receptor (ER)-mediated signaling.
Methods: A phase Ia/Ib/IIa dose escalation, combination treatment with palbociclib or a luteinizing hormone-releasing hormone, and expansion study determined the safety, pharmacokinetics, and recommended phase 2 dose (RP2D) of GDC-0810 in postmenopausal women with ER + (HER2 -) locally advanced or metastatic breast cancer (MBC). Baseline plasma ctDNA samples were analyzed to determine the ESR1 mutation status.
Purpose: We developed a method to monitor copy number variations (CNV) in plasma cell-free DNA (cfDNA) from patients with metastatic squamous non-small cell lung cancer (NSCLC). We aimed to explore the association between tumor-derived cfDNA and clinical outcomes, and sought CNVs that may suggest potential resistance mechanisms.
Experimental Design: Sensitivity and specificity of low-pass whole-genome sequencing (LP-WGS) were first determined using cell line DNA and cfDNA.
Background: This phase Ib study (NCT00960960) evaluated pictilisib (GDC-0941; pan-phosphatidylinositol 3-kinase inhibitor) plus paclitaxel, with and without bevacizumab or trastuzumab, or in combination with letrozole, in patients with locally recurrent or metastatic breast cancer.
Methods: This was a three-part multischedule study. Patients in parts 1 and 2, which comprised 3 + 3 dose escalation and cohort expansion stages, received pictilisib (60-330 mg) plus paclitaxel (90 mg/m) with and without bevacizumab (10 mg/kg) or trastuzumab (2-4 mg/kg).
Genomic profiling of circulating tumor DNA derived from cell-free DNA (cfDNA) in blood can provide a noninvasive method for detecting genomic biomarkers to guide clinical decision making for cancer patients. We developed a hybrid capture-based next-generation sequencing assay for genomic profiling of circulating tumor DNA from blood (FoundationACT). High-sequencing coverage and molecular barcode-based error detection enabled accurate detection of genomic alterations, including short variants (base substitutions, short insertions/deletions) and genomic re-arrangements at low allele frequencies (AFs), and copy number amplifications.
View Article and Find Full Text PDFBackground: Epidermal growth factor receptor (EGFR) and phosphatidylinositol 3-kinase (PI3K) are involved in the proliferation and survival of many cancer types. Enhanced antitumor activity may be achieved through combined inhibition of these pathways. We report results for pictilisib (GDC-0941, a class I pan-PI3K inhibitor) plus erlotinib (an EGFR tyrosine kinase inhibitor) in patients with advanced solid tumors.
View Article and Find Full Text PDFBreast cancer is a heterogeneous disease and patients are managed clinically based on ER, PR, HER2 expression, and key risk factors. We sought to characterize the molecular landscape of high-risk breast cancer patients enrolled onto an adjuvant chemotherapy study to understand how disease subsets and tumor immune status impact survival. DNA and RNA were extracted from 861 breast cancer samples from patients enrolled onto the United States Oncology trial 01062.
View Article and Find Full Text PDFBackground: The current single-arm, open-label trial was designed to evaluate the activity of apitolisib (GDC-0980), a dual phosphoinositide 3-kinase/mammalian target of rapamycin (PI3K/mTOR) inhibitor, in patients with advanced endometrial cancer (EC).
Methods: Patients with recurrent or persistent EC who were treated with 1 to 2 prior lines of chemotherapy but no prior PI3K/mTOR inhibitor received oral apitolisib at a dose of 40 mg daily during 28-day cycles until disease progression or intolerable toxicity occurred. Patients with type I/II diabetes who required insulin were excluded.
Mutations in ESR1 have been associated with resistance to aromatase inhibitor (AI) therapy in patients with ER+ metastatic breast cancer. Little is known of the impact of these mutations in patients receiving selective oestrogen receptor degrader (SERD) therapy. In this study, hotspot mutations in ESR1 and PIK3CA from ctDNA were assayed in clinical trial samples from ER+ metastatic breast cancer patients randomized either to the SERD fulvestrant or fulvestrant plus a pan-PI3K inhibitor.
View Article and Find Full Text PDFPurpose: To the best of our knowledge, this study is the first to compare dual inhibition of PI3K/mammalian target of rapamycin (mTOR) by apitolisib (GDC-0980) against single inhibition of mTORC1 by everolimus in metastatic renal cell carcinoma (mRCC).
Patients And Methods: Patients with clear-cell mRCC who progressed on or after vascular endothelial growth factor-targeted therapy were randomly assigned to apitolisib 40 mg once per day or to everolimus 10 mg once per day. End points included progression-free survival, safety, overall survival, and objective response rate.
Purpose: This first-in-human phase I trial assessed the safety, tolerability, and preliminary antitumor activity of apitolisib (GDC-0980), a dual inhibitor of class I PI3K, and mTOR kinases.
Experimental Design: Once-daily oral apitolisib was administered to patients with solid tumors for days 1 to 21 or 1 to 28 of 28-day cycles. Pharmacokinetic and pharmacodynamic parameters were assessed.
Activation of the PI3K pathway occurs commonly in a wide variety of cancers. Experience with other successful targeted agents suggests that clinical resistance is likely to arise and may reduce the durability of clinical benefit. Here, we sought to understand mechanisms underlying resistance to PI3K inhibition in PTEN-deficient cancers.
View Article and Find Full Text PDFPurpose: This first-in-human dose-escalation trial evaluated the safety, tolerability, maximal-tolerated dose (MTD), dose-limiting toxicities (DLT), pharmacokinetics, pharmacodynamics, and preliminary clinical activity of pictilisib (GDC-0941), an oral, potent, and selective inhibitor of the class I phosphatidylinositol-3-kinases (PI3K).
Patients And Methods: Sixty patients with solid tumors received pictilisib at 14 dose levels from 15 to 450 mg once-daily, initially on days 1 to 21 every 28 days and later, using continuous dosing for selected dose levels. Pharmacodynamic studies incorporated (18)F-FDG-PET, and assessment of phosphorylated AKT and S6 ribosomal protein in platelet-rich plasma (PRP) and tumor tissue.
Breast cancers are categorized into three subtypes based on protein expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2/ERBB2). Patients enroll onto experimental clinical trials based on ER, PR, and HER2 status and, as receptor status is prognostic and defines treatment regimens, central receptor confirmation is critical for interpreting results from these trials. Patients enrolling onto experimental clinical trials in the metastatic setting often have limited available archival tissue that might better be used for comprehensive molecular profiling rather than slide-intensive reconfirmation of receptor status.
View Article and Find Full Text PDFPatients with newly diagnosed, early stage estrogen receptor positive (ER+) breast cancer often show disease free survival in excess of five years following surgery and systemic adjuvant therapy. An important question is whether diagnostic tumor tissue from the primary lesion offers an accurate molecular portrait of the cancer post recurrence and thus may be used for predictive diagnostic purposes for patients with relapsed, metastatic disease. As the class I phosphatidylinositol 3' kinase (PI3K) pathway is frequently activated in ER+ breast cancer and has been linked to acquired resistance to hormonal therapy, we hypothesized pathway status could evolve over time and treatment.
View Article and Find Full Text PDFPurpose: Class 1 phosphatidylinositol 3-kinase (PI3K) plays a major role in cell proliferation and survival in a wide variety of human cancers. Here, we investigated biomarker strategies for PI3K pathway inhibitors in non-small-cell lung cancer (NSCLC).
Experimental Design: Molecular profiling for candidate PI3K predictive biomarkers was conducted on a collection of NSCLC tumor samples.
The RAS/RAF/MEK pathway is activated in more than 30% of human cancers, most commonly via mutation in the K-ras oncogene and also via mutations in BRAF. Several allosteric mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitors, aimed at treating tumors with RAS/RAF pathway alterations, are in clinical development. However, acquired resistance to these inhibitors has been documented both in preclinical and clinical samples.
View Article and Find Full Text PDFAlterations of the phosphoinositide-3 kinase (PI3K)/Akt signaling pathway occur broadly in cancer via multiple mechanisms including mutation of the PIK3CA gene, loss or mutation of phosphatase and tensin homolog (PTEN), and deregulation of mammalian target of rapamycin (mTOR) complexes. The dysregulation of this pathway has been implicated in tumor initiation, cell growth and survival, invasion and angiogenesis, thus, PI3K and mTOR are promising therapeutic targets for cancer. We discovered GDC-0980, a selective, potent, orally bioavailable inhibitor of Class I PI3 kinase and mTOR kinase (TORC1/2) with excellent pharmacokinetic and pharmaceutical properties.
View Article and Find Full Text PDFBackground: Evaluation of cancer biomarkers from blood could significantly enable biomarker assessment by providing a relatively non-invasive source of representative tumor material. Circulating Tumor Cells (CTCs) isolated from blood of metastatic cancer patients hold significant promise in this regard.
Methodology/principal Findings: Using spiked tumor-cells we evaluated CTC capture on different CTC technology platforms, including CellSearch and two biochip platforms, and used the isolated CTCs to develop and optimize assays for molecular characterization of CTCs.
Rheumatoid arthritis (RA) is the most common systemic autoimmune disease, affecting approximately 1% of the adult population worldwide, with an estimated heritability of 60%. To identify genes involved in RA susceptibility, we investigated the association between putative functional single-nucleotide polymorphisms (SNPs) and RA among white individuals by use of a case-control study design; a second sample was tested for replication. Here we report the association of RA susceptibility with the minor allele of a missense SNP in PTPN22 (discovery-study allelic P=6.
View Article and Find Full Text PDFGeographic variation in the mutualism between the legume Amphicarpaea bracteata and its nitrogen-fixing root nodule bacteria (Bradyrhizobium sp.) was analyzed by sampling genotypes from 11 sites separated by distances ranging from 0.6 km to more than 1000 km.
View Article and Find Full Text PDFGenetically divergent lineages often coexist within populations of the annual legume Amphicarpaea bracteata. At one site dominated by two such lineages (termed biotypes "C" and "S"), isolates of root-nodule bacteria (Bradyrhizobium sp.) were sampled from both hosts and analyzed by enzyme electrophoresis.
View Article and Find Full Text PDF