538 research outputs found
Palbociclib: a first-in-class CDK4/CDK6 inhibitor for the treatment of hormone-receptor positive advanced breast cancer
Palbociclib was approved by the FDA for use in combination with letrozole for the treatment of postmenopausal women with hormone-receptor-positive, HER2-negative advanced breast cancer as initial endocrine-based therapy. In addition, the combination of palbociclib with fulvestrant resulted in superior outcome than fulvestrant alone in those who had progressed during prior endocrine therapy. This research highlight summarized the current development of CDK4/CDK6 inhibitors and future directions in the treatment of advanced hormone-receptor-positive breast cancer
Integrated mapping of pharmacokinetics and pharmacodynamics in a patient-derived xenograft model of glioblastoma
Therapeutic options for the treatment of glioblastoma remain inadequate despite concerted research efforts in drug development. Therapeutic failure can result from poor permeability of the blood-brain barrier, heterogeneous drug distribution, and development of resistance. Elucidation of relationships among such parameters could enable the development of predictive models of drug response in patients and inform drug development. Complementary analyses were applied to a glioblastoma patient-derived xenograft model in order to quantitatively map distribution and resulting cellular response to the EGFR inhibitor erlotinib. Mass spectrometry images of erlotinib were registered to histology and magnetic resonance images in order to correlate drug distribution with tumor characteristics. Phosphoproteomics and immunohistochemistry were used to assess protein signaling in response to drug, and integrated with transcriptional response using mRNA sequencing. This comprehensive dataset provides simultaneous insight into pharmacokinetics and pharmacodynamics and indicates that erlotinib delivery to intracranial tumors is insufficient to inhibit EGFR tyrosine kinase signaling.National Institutes of Health (U.S.) (U54 CA210180)MIT/Mayo Physical Sciences Center for Drug Distribution and Drug Efficacy in Brain TumorsDana-Farber Cancer Institute (PLGA Fund)Lundbeck FoundationNovo Nordisk Foundatio
Integrated Proteogenomic Analysis Reveals Distinct Potentially Actionable Therapeutic Vulnerabilities in Triple-Negative Breast Cancer Subtypes
Triple-negative breast cancer (TNBC) is characterized by an aggressive clinical presentation and a paucity of clinically actionable genomic alterations. Here, we utilized the Cancer Genome Atlas (TCGA) to explore the proteogenomic landscape of TNBC subtypes to see whether genomic alterations can be inferred from proteomic data. We found only 4% of the protein level changes are explained by mutations, while 21% of the protein and 35% of the transcriptomics changes were determined by copy number alterations (CNAs). We found tighter coupling between proteome and genome in some genes that are predicted to be the targets of drug inhibitors, including CDKs, PI3K, tyrosine kinase (TKI), and mTOR. The validation of our proteogenomic workflow using mass spectrometry Clinical Proteomic Tumor Analysis Consortium (MS-CPTAC) data also demonstrated the highest correlation between protein-RNA-CNA. The integrated proteogenomic approach helps to prioritize potentially actionable targets and may enable the acceleration of personalized cancer treatment
Nanoparticle-based 3D membrane for impedimetric biosensor applications
This paper reports on a comparison between nano-ZnO/CuO and nano-ZnO nitrocellulose membrane biosensors, both of which were fabricated using a simple and inexpensive sonication technique. To produce the nano-ZnO/CuO membranes, the technique involved sonication of 1% (w/v) ZnO and 1% (w/v) CuO nano-crystal colloidal suspensions, with a volume ratio of 1:2. The membranes were analysed by scanning electron microscopy and energy-dispersive spectroscopy, which showed the gradated distribution of nanoparticles in the membrane. Impedance spectroscopy demonstrated that the sonication resulted in a greater than two-fold enhancement of the output signal. Changes in impedance phase values, at a frequency of 100 Hz, were used to establish dose dependent responses for C-reactive protein (CRP). Limits of detection of 27 pg/mL for the 1% (w/v) nano-ZnO and 16 pg/mL for the 1% (w/v) nano-ZnO/CuO nitrocellulose membrane biosensors were demonstrated
Preclinical Investigations of the Efficacy of the Glutaminase Inhibitor CB-839 Alone and in Combinations in Chronic Lymphocytic Leukemia
INTRODUCTION: Chronic lymphocytic leukemia (CLL) cells are metabolically flexible and adapt to modern anticancer treatments. Bruton tyrosine kinase (BTK) and B-cell lymphoma-2 (BCL-2) inhibitors have been widely used to treat CLL, but CLL cells become resistant to these treatments over time. CB-839 is a small-molecule glutaminase-1 (GLS-1) inhibitor that impairs glutamine use, disrupts downstream energy metabolism, and impedes the elimination of reactive oxygen species.
METHODS: To investigate the
RESULTS: We found that CB-839 caused dose-dependent decreases in GLS-1 activity and glutathione synthesis. CB-839-treated cells also showed increased mitochondrial superoxide metabolism and impaired energy metabolism, which were reflected in decreases in the oxygen consumption rate and depletion of the adenosine triphosphate pool and led to the inhibition of cell proliferation. In the cell lines, CB-839 combined with venetoclax or AZD-5991, but not with ibrutinib, demonstrated synergism with an increased apoptosis rate and cell proliferation inhibition. In the primary lymphocytes, no significant effects of CB-839 alone or in combination with venetoclax, ibrutinib, or AZD-5991 were observed.
DISCUSSION: Our findings suggest that CB-839 has limited efficacy in CLL treatment and shows limited synergy in combination with widely used CLL drugs
Crizotinib Enhances PARP Inhibitor Efficacy in Ovarian Cancer Cells and Xenograft Models by Inducing Autophagy
Poly (ADP-ribose) polymerase inhibitors (PARPi) can encounter resistance through various mechanisms, limiting their effectiveness. Our recent research showed that PARPi alone can induce drug resistance by promoting autophagy. Moreover, our studies have revealed that anaplastic lymphoma kinase (ALK) plays a role in regulating the survival of ovarian cancer cells undergoing autophagy. Here, we explored whether the ALK-inhibitor crizotinib could enhance the efficacy of PARPi by targeting drug-induced autophagic ovarian cancer cell and xenograft models. Our investigation demonstrates that crizotinib enhances the anti-tumor activity of PARPi across multiple ovarian cancer cells. Combination therapy with crizotinib and olaparib reduced cell viability and clonogenic growth in two-olaparib resistant cell lines. More importantly, this effect was consistently observed in patient-derived organoids. Furthermore, combined treatment with crizotinib and olaparib led to tumor regression in human ovarian xenograft models. Mechanistically, the combination resulted in increased levels of reactive oxygen species (ROS), induced DNA damage, and decreased the phosphorylation of AKT, mTOR, and ULK-1, contributing to increased olaparib-induced autophagy and apoptosis. Notably, pharmacologic, or genetic inhibition or autophagy reduced the sensitivity of ovarian cancer cell lines to olaparib and crizotinib treatment, underscoring the role of autophagy in cell death. Blocking ROS mitigated olaparib/crizotinib-induced autophagy and cell death while restoring levels of phosphorylated AKT, mTOR and ULK-1. These findings suggest that crizotinib can improve the therapeutic efficacy of olaparib by enhancing autophagy. Implications: The combination of crizotinib and PARPi presents a promising strategy, that could provide a novel approach to enhance outcomes for patients with ovarian cancer.
Implications: The combination of crizotinib and PARPi presents a promising strategy, that could provide a novel approach to enhance outcomes for patients with ovarian cancer
A genome-wide association study of the frailty index highlights brain pathways in ageing
Frailty is a common geriatric syndrome and strongly associated with disability, mortality and hospitalization. Frailty is commonly measured using the frailty index (FI), based on the accumulation of a number of health deficits during the life course. The mechanisms underlying FI are multifactorial and not well understood, but a genetic basis has been suggested with heritability estimates between 30 and 45%. Understanding the genetic determinants and biological mechanisms underpinning FI may help to delay or even prevent frailty. We performed a genome-wide association study (GWAS) meta-analysis of a frailty index in European descent UK Biobank participants (n = 164,610, 60–70 years) and Swedish TwinGene participants (n = 10,616, 41–87 years). FI calculation was based on 49 or 44 self-reported items on symptoms, disabilities and diagnosed diseases for UK Biobank and TwinGene, respectively. 14 loci were associated with the FI (p < 5*10−8). Many FI-associated loci have established associations with traits such as body mass index, cardiovascular disease, smoking, HLA proteins, depression and neuroticism; however, one appears to be novel. The estimated single nucleotide polymorphism (SNP) heritability of the FI was 11% (0.11, SE 0.005). In enrichment analysis, genes expressed in the frontal cortex and hippocampus were significantly downregulated (adjusted p < 0.05). We also used Mendelian randomization to identify modifiable traits and exposures that may affect frailty risk, with a higher educational attainment genetic risk score being associated with a lower degree of frailty. Risk of frailty is influenced by many genetic factors, including well-known disease risk factors and mental health, with particular emphasis on pathways in the brain
Correction to: Circulating Tumor Cell Transcriptomics as Biopsy Surrogates in Metastatic Breast Cancer
Circulating Tumor Cell Transcriptomics as Biopsy Surrogates in Metastatic Breast Cancer
BACKGROUND
Metastatic breast cancer (MBC) and the circulating tumor cells (CTCs) leading to macrometastases are inherently different than primary breast cancer. We evaluated whether whole transcriptome RNA-Seq of CTCs isolated via an epitope-independent approach may serve as a surrogate for biopsies of macrometastases.
METHODS
We performed RNA-Seq on fresh metastatic tumor biopsies, CTCs, and peripheral blood (PB) from 19 newly diagnosed MBC patients. CTCs were harvested using the ANGLE Parsortix microfluidics system to isolate cells based on size and deformability, independent of a priori knowledge of cell surface marker expression.
RESULTS
Gene expression separated CTCs, metastatic biopsies, and PB into distinct groups despite heterogeneity between patients and sample types. CTCs showed higher expression of immune oncology targets compared with corresponding metastases and PB. Predictive biomarker (n = 64) expression was highly concordant for CTCs and metastases. Repeat observation data post-treatment demonstrated changes in the activation of different biological pathways. Somatic single nucleotide variant analysis showed increasing mutational complexity over time.
CONCLUSION
We demonstrate that RNA-Seq of CTCs could serve as a surrogate biomarker for breast cancer macrometastasis and yield clinically relevant insights into disease biology and clinically actionable targets
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