ABSTRACT
Measurement of monoclonal antibodies (M-proteins) plays an important role in the diagnosis and treatment monitoring of multiple myeloma. Currently available M-protein assays have several limitations, particularly because of their lack of sensitivity and propensity to therapeutic antibody (t-mAb) interference. A previously described mass spectrometry method termed monoclonal immunoglobulin rapid accurate mass measurement (miRAMM) is more sensitive than current clinical tests and can provide a solution for resolving t-mAb interferences. However, the original miRAMM workflow is too complex for the throughput needed to analyze a large number of samples. Here, we describe a high-throughput liquid chromatography-high-resolution mass spectrometry (HT-LC-HRMS) approach that employs a fully automated immunocapture step, significantly improved immunoglobulin recovery, simplified chromatography, and high throughput (HT) data processing. In this HT-LC-HRMS approach, raw spectra of the peaks eluting from the LC column during the predefined time period are automatically deconvoluted without the need to identify and monitor the retention time of each patient-specific M-protein. The deconvoluted peak heights of M-protein and therapeutic antibody light chain are conveniently used for quantitation. With the total LC-HRMS measurement time being only 11.0 min, this method was able to differentiate between the M-protein and elotuzumab mass signatures in 91 out of 92 (98.9%) multiple myeloma serum samples tested. The single interference case was resolved using the mass signature of a heavy chain. In addition to resolving t-mAb interference, the developed assay has a 25-fold improvement in sensitivity over immunofixation electrophoresis and can potentially provide an objective tracking of M-proteins in patients with complete response.
Subject(s)
Antibodies, Monoclonal, Humanized/chemistry , High-Throughput Screening Assays/methods , Immunoglobulins/metabolism , Mass Spectrometry/methods , Multiple Myeloma/metabolism , Antibodies, Monoclonal, Humanized/therapeutic use , Antineoplastic Agents/chemistry , Chromatography, Liquid/methods , Humans , Immunoglobulins/chemistry , Multiple Myeloma/drug therapy , Sensitivity and SpecificityABSTRACT
Familial hypercholesterolemia (FH) is a monogenic disease characterized by a lifelong exposure to high LDL-C levels that can lead to early onset coronary heart disease (CHD). The main causes of FH identified to date include loss-of-function mutations in LDLR or APOB, or gain-of-function mutations in PCSK9. Early diagnosis and genetic testing of FH suspects is critical for improved prognosis of affected individuals as lipid lowering treatments are effective in preventing CHD related morbidity and mortality. In the present study, we carried out a comprehensive screening, using a next-generation sequencing (NGS) panel, for FH culprit mutations in two Icelandic studies representative of either FH families or the general population. We confirmed all previously known mutations in the FH families, and identified two subjects that had been misdiagnosed clinically at young age. We identified six new mutations in the Icelandic FH families and detected three pathogenic mutations in the general population-based study. The application of the NGS panel revealed substantial diagnostic yields in identifying pathogenic mutations, or 68.2% of those with definite clinical diagnosis of FH in the family material and 5.6-fold enrichment in the population-based genetic testing.
Subject(s)
Genetic Testing/methods , Hyperlipoproteinemia Type II/diagnosis , Genetic Predisposition to Disease , High-Throughput Nucleotide Sequencing , Humans , Hyperlipoproteinemia Type II/genetics , Iceland , Loss of Function Mutation , Mutation , Prospective StudiesABSTRACT
PURPOSE: To study the incidence of tumor suppressor gene (TSG) mutations in men and women with impaired gametogenesis. METHODS: Gene association analyses were performed on blood samples in two distinct patient populations: males with idiopathic male infertility and females with unexplained diminished ovarian reserve (DOR). The male study group consisted of men with idiopathic azoospermia, oligozoospermia, asthenozoospermia, or teratozoospermia. Age-matched controls were men with normal semen analyses. The female study group consisted of women with unexplained DOR with anti-Müllerian hormone levels ≤ 1.1 ng/mL. Controls were age-matched women with normal ovarian reserve (> 1.1 ng/mL). RESULTS: Fifty-seven male cases (mean age = 38.4; mean sperm count = 15.7 ± 12.1; mean motility = 38.2 ± 24.7) and 37 age-matched controls (mean age = 38.0; mean sperm count = 89.6 ± 37.5; mean motility = 56.2 ± 14.3) were compared. Variants observed in CHD5 were found to be enriched in the study group (p = 0.000107). The incidence of CHD5 mutation c.*3198_*3199insT in the 3'UTR (rs538186680) was significantly higher in cases compared to controls (p = 0.0255). 72 DOR cases (mean age = 38.7; mean AMH = 0.5 ± 0.3; mean FSH = 11.7 ± 12.5) and 48 age-matched controls (mean age = 37.6; mean AMH = 4.1 ± 3.0; mean FSH = 7.1 ± 2.2) were compared. Mutations in CHD5 (c.-140A>C), RB1 (c.1422-18delT, rs70651121), and TP53 (c.376-161A>G, rs75821853) were found at significantly higher frequencies in DOR cases compared to controls (p ≤ 0.05). In addition, 363 variants detected in the DOR patients were not present in the control group. CONCLUSION: Unexplained impaired gametogenesis in both males and females may be associated with genetic variation in TSGs. TSGs, which play cardinal roles in cell-cycle control, might also be critical for normal spermatogenesis and oogenesis. If validated in larger prospective studies, it is possible that TSGs provide an etiological basis for some patients with impaired gametogenesis.
Subject(s)
Infertility, Female/genetics , Infertility, Male/genetics , Ovarian Reserve/genetics , Spermatogenesis/genetics , Adult , DNA Helicases/genetics , Female , Gametogenesis/genetics , Genes, Tumor Suppressor , Genetic Association Studies , Genetic Predisposition to Disease , Humans , Infertility, Female/pathology , Infertility, Male/pathology , Male , Mutation/genetics , Nerve Tissue Proteins/genetics , Retinoblastoma Binding Proteins/genetics , Sperm Count , Sperm Motility/genetics , Spermatozoa/pathology , Tumor Suppressor Protein p53/genetics , Ubiquitin-Protein Ligases/geneticsABSTRACT
BACKGROUND: Codrituzumab, a humanized monoclonal antibody against Glypican-3 (GPC3), which is expressed in hepatocellular carcinoma (HCC), was tested in a randomized phase II trial in advanced HCC patients who had failed prior systemic therapy. Biomarker analysis was performed to identify a responder population that benefits from treatment. METHODS: A novel statistical method based on the Indian buffet process (IBP) was used to identify biomarkers predictive of response to treatment with Codrituzumab. The IBP is a novel method that allows flexibility in analysis design, and which is sensitive to slight, but meaningful between-group differences in biomarkers in very complex datasets RESULTS: The IBP model identified several subpopulations of patients having defined biomarker values. Tumor necrosis and viable cell content in the tumor were identified as prognostic markers of disease progression, as were the well-known HCC prognostic markers of disease progression, alpha-fetoprotein and Glypican-3 expression. Predictive markers of treatment response included natural killer (NK) cell surface markers and parameters influencing NK cell activity, all related to the mechanism of action of this drug CONCLUSIONS: The Indian buffet process can be effectively used to detect statistically significant signals with high sensitivity in complex and noisy biological data TRIAL REGISTRATION: NCT01507168 , January 6, 2012.
Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/drug therapy , Liver Neoplasms/drug therapy , Antibodies, Monoclonal, Humanized/pharmacology , Carcinoma, Hepatocellular/metabolism , Case-Control Studies , Disease Progression , Female , Gene Expression Regulation, Neoplastic/drug effects , Glypicans/metabolism , Humans , Liver Neoplasms/metabolism , Male , Models, Statistical , Survival Analysis , Treatment Outcome , alpha-Fetoproteins/metabolismABSTRACT
PURPOSE: To develop a comprehensive genetic test for female and male infertility in support of medical decisions during assisted reproductive technology (ART) protocols. METHODS: We developed a next-generation sequencing (NGS) gene panel consisting of 87 genes including promoters, 5' and 3' untranslated regions, exons, and selected introns. In addition, sex chromosome aneuploidies and Y chromosome microdeletions were analyzed concomitantly using the same panel. RESULTS: The NGS panel was analytically validated by retrospective analysis of 118 genomic DNA samples with known variants in loci representative of female and male infertility. Our results showed analytical accuracy of > 99%, with > 98% sensitivity for single-nucleotide variants (SNVs) and > 91% sensitivity for insertions/deletions (indels). Clinical sensitivity was assessed with samples containing variants representative of male and female infertility, and it was 100% for SNVs/indels, CFTR IVS8-5T variants, sex chromosome aneuploidies, and copy number variants (CNVs) and > 93% for Y chromosome microdeletions. Cost analysis shows potential savings when comparing this single NGS assay with the standard approach, which includes multiple assays. CONCLUSIONS: A single, comprehensive, NGS panel can simplify the ordering process for healthcare providers, reduce turnaround time, and lower the overall cost of testing for genetic assessment of infertility in females and males, while maintaining accuracy.
Subject(s)
Genetic Testing , High-Throughput Nucleotide Sequencing , Infertility, Female/genetics , Infertility, Male/genetics , DNA Copy Number Variations/genetics , Exons , Female , Humans , INDEL Mutation/genetics , Infertility, Female/diagnosis , Infertility, Female/pathology , Infertility, Male/diagnosis , Infertility, Male/pathology , Male , Polymorphism, Single Nucleotide/geneticsABSTRACT
BACKGROUND: Current professional society guidelines recommend genetic carrier screening be offered on the basis of ethnicity, or when using expanded carrier screening panels, they recommend to compute residual risk based on ethnicity. We investigated the reliability of self-reported ethnicity in 9138 subjects referred to carrier screening. Self-reported ethnicity gathered from test requisition forms and during post-test genetic counseling, and genetic ancestry predicted by a statistical model, were compared for concordance. RESULTS: We identified several discrepancies between the two sources of self-reported ethnicity and genetic ancestry. Only 30.3% of individuals who indicated Mediterranean ancestry during consultation self-reported this on requisition forms. Additionally, the proportion of individuals who reported Southeast Asian but were estimated to have a different genetic ancestry was found to depend on the source of self-report. Finally, individuals who reported Latin American demonstrated a high degree of ancestral admixture. As a result, carrier rates and residual risks provided for patient decision-making are impacted if using self-reported ethnicity. CONCLUSION: Our analysis highlights the unreliability of ethnicity classification based on patient self-reports. We recommend the routine use of pan-ethnic carrier screening panels in reproductive medicine. Furthermore, the use of an ancestry model would allow better estimation of carrier rates and residual risks.
Subject(s)
Ethnicity/genetics , Genetic Carrier Screening , Racial Groups/genetics , Self Report , Human Genome Project , Humans , Models, Genetic , Polymorphism, Single NucleotideABSTRACT
BACKGROUND: Alectinib--a highly selective, CNS-active, ALK inhibitor-showed promising clinical activity in crizotinib-naive and crizotinib-resistant patients with ALK-rearranged (ALK-positive) non-small-cell lung cancer (NSCLC). We aimed to assess the safety and efficacy of alectinib in patients with ALK-positive NSCLC who progressed on previous crizotinib. METHODS: We did a phase 2 study at 27 centres in the USA and Canada. We enrolled patients aged 18 years or older with stage IIIB-IV, ALK-positive NSCLC who had progressed after crizotinib. Patients were treated with oral alectinib 600 mg twice daily until progression, death, or withdrawal. The primary endpoint was the proportion of patients achieving an objective response by an independent review committee using Response Evaluation Criteria in Solid Tumors, version 1.1. Response endpoints were assessed in the response-evaluable population (ie, patients with measurable disease at baseline who received at least one dose of study drug), and efficacy and safety analyses were done in the intention-to-treat population (all enrolled patients). This study is registered with ClinicalTrials.gov, number NCT01871805. The study is ongoing and patients are still receiving treatment. FINDINGS: Between Sept 4, 2013, and Aug 4, 2014, 87 patients were enrolled into the study (intention-to-treat population). At the time of the primary analysis (median follow-up 4·8 months [IQR 3·3-7·1]), 33 of 69 patients with measurable disease at baseline had a confirmed partial response; thus, the proportion of patients achieving an objective response by the independent review committee was 48% (95% CI 36-60). Adverse events were predominantly grade 1 or 2, most commonly constipation (31 [36%]), fatigue (29 [33%]), myalgia 21 [24%]), and peripheral oedema 20 [23%]). The most common grade 3 and 4 adverse events were changes in laboratory values, including increased blood creatine phosphokinase (seven [8%]), increased alanine aminotransferase (five [6%]), and increased aspartate aminotransferase (four [5%]). Two patients died: one had a haemorrhage (judged related to study treatment), and one had disease progression and a history of stroke (judged unrelated to treatment). INTERPRETATION: Alectinib showed clinical activity and was well tolerated in patients with ALK-positive NSCLC who had progressed on crizotinib. Therefore, alectinib could be a suitable treatment for patients with ALK-positive disease who have progressed on crizotinib. FUNDING: F Hoffmann-La Roche.
Subject(s)
Antineoplastic Agents/therapeutic use , Carbazoles/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Piperidines/therapeutic use , Adult , Aged , Alanine Transaminase/blood , Anaplastic Lymphoma Kinase , Antineoplastic Agents/adverse effects , Aspartate Aminotransferases/blood , Carbazoles/adverse effects , Carcinoma, Non-Small-Cell Lung/enzymology , Constipation/chemically induced , Creatine Kinase/blood , Crizotinib , Drug Resistance, Neoplasm , Edema/chemically induced , Fatigue/chemically induced , Female , Humans , Lung Neoplasms/enzymology , Male , Middle Aged , Myalgia/chemically induced , Piperidines/adverse effects , Pyrazoles/therapeutic use , Pyridines/therapeutic use , Receptor Protein-Tyrosine Kinases/analysis , Receptor Protein-Tyrosine Kinases/antagonists & inhibitors , Response Evaluation Criteria in Solid Tumors , RetreatmentABSTRACT
BACKGROUND & AIMS: Codrituzumab, a humanized monoclonal antibody against Glypican-3 (GPC3) that is expressed in hepatocellular carcinoma (HCC), interacts with CD16/FcγRIIIa and triggers antibody-dependent cytotoxicity. Codrituzumab was studied vs. placebo in a randomized phase II trial in advanced HCC patients who had failed prior systemic therapy. METHODS: Patients with advanced HCC who had failed prior systemic therapy, ⩾18years, Eastern cooperative oncology group (ECOG) 0-1, Child-Pugh A were randomized 2:1 to biweekly codrituzumab 1600mg vs. placebo. Patients were stratified based on GPC3 immunohistochemical expression: 2+/3+, 1+, and 0. Primary endpoint was progression free survival. Secondary endpoints include overall survival (OS), tolerability, pharmacokinetics, and an exploratory endpoint in biomarkers analysis. RESULTS: 185 patients were enrolled: 125 received codrituzumab and 60 placebo: Median age 64/63, 85/75% male, 46/42% Asian, ECOG 0 65/63%, 74/77% having vascular invasion and/or extra-hepatic metastasis. 84%/70% had prior sorafenib. Drug exposure was 98.4% of planned dose, with an identical adverse events profile between the 2 groups. The median progression free survival and overall survival in the codrituzumab vs. placebo groups in months were: 2.6 vs. 1.5 (hazard ratios 0.97, p=0.87), and 8.7 vs. 10 (hazard ratios 0.96, p=0.82). Projected Ctrough at cycle 3day 1 based exposure, high CD16/FcγRIIIa on peripheral immune cells, and GPC3 expression in the tumor, were all associated with prolonged progression free survival and overall survival. CONCLUSIONS: Codrituzumab did not show clinical benefit in this previously treated HCC population. Whether higher codrituzumab drug exposure or the use of CD16 and GPC3 as potential biomarkers would improve outcome remain unanswered questions. LAY SUMMARY: Codrituzumab is a manufactured antibody against a liver cancer protein called glypican-3. In this clinical trial, codrituzumab was not found be effective against liver cancer. It was suggested though that a higher dose of codrituzumab or selecting patients with high level of glypican-3 or its mediator CD16 might improve outcome. CLINICAL TRIAL REGISTRATION: This trial is registered at Clinicaltrials.gov (NCT01507168).
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Antibodies, Monoclonal, Humanized , Disease-Free Survival , Double-Blind Method , Female , Glypicans , Humans , Male , Middle Aged , Treatment OutcomeABSTRACT
The pharmaceutical industry is spending increasingly large amounts of money on the discovery and development of novel medicines, but this investment is not adequately paying off in an increased rate of newly approved drugs by the FDA. The post-genomic era has provided a wealth of novel approaches for generating large, high-dimensional genetic and transcriptomic data sets from large cohorts of preclinical species as well as normal and diseased individuals. This systems biology approach to understanding disease-related biology is revolutionizing our understanding of the cellular pathways and gene networks underlying the onset of disease, and the mechanisms of pharmacological treatments that ameliorate disease phenotypes. In this article, we review a number of approaches being used by pharmaceutical and biotechnology companies, e.g., high-throughput DNA genotyping, sequencing, and genome-wide gene expression profiling, to enable drug discovery and development through the identification of new drug targets and biomarkers of disease progression, drug pharmacodynamics, and predictive markers for selecting the patients most likely to respond to therapy.
Subject(s)
Drug Discovery/methods , Systems Biology/methods , Aging , Animals , Biomarkers , Gene Regulatory Networks , Genetics , Humans , Polymorphism, Single Nucleotide , PrognosisABSTRACT
In an attempt to understand the applicability of various animal models to dyslipidemia in humans and to identify improved preclinical models for target discovery and validation for dyslipidemia, we measured comprehensive plasma lipid profiles in 24 models. These included five mouse strains, six other nonprimate species, and four nonhuman primate (NHP) species, and both healthy animals and animals with metabolic disorders. Dyslipidemic humans were assessed by the same measures. Plasma lipoprotein profiles, eight major plasma lipid fractions, and FA compositions within these lipid fractions were compared both qualitatively and quantitatively across the species. Given the importance of statins in decreasing plasma low-density lipoprotein cholesterol for treatment of dyslipidemia in humans, the responses of these measures to simvastatin treatment were also assessed for each species and compared with dyslipidemic humans. NHPs, followed by dog, were the models that demonstrated closest overall match to dyslipidemic humans. For the subset of the dyslipidemic population with high plasma triglyceride levels, the data also pointed to hamster and db/db mouse as representative models for practical use in target validation. Most traditional models, including rabbit, Zucker diabetic fatty rat, and the majority of mouse models, did not demonstrate overall similarity to dyslipidemic humans in this study.
Subject(s)
Disease Models, Animal , Dyslipidemias/blood , Lipids/blood , Animals , Cricetinae , Dogs , Dyslipidemias/drug therapy , Fatty Acids/blood , Humans , Mice , Primates , Simvastatin/therapeutic use , Triglycerides/bloodABSTRACT
Metabolic syndrome is a combination of medical disorders that increases the risk of developing cardiovascular disease and diabetes. Constitutive overexpression of 11ß-HSD1 in adipose tissue in mice leads to metabolic syndrome. In the process of generating transgenic mice overexpressing 11ß-HSD1 in an inducible manner, we found a metabolic syndrome phenotype in control, transgenic mice, expressing the reverse tetracycline-transactivator (rtTA) in adipose tissue. The control mice exhibited all four sequelae of metabolic syndrome (visceral obesity, insulin resistance, dyslipidemia, and hypertension), a pro-inflammatory state and marked hepatic steatosis. Gene expression profiling of the adipose tissue, muscle and liver of these mice revealed changes in expression of genes involved in lipid metabolism, insulin resistance, and inflammation. Transient transfection of rtTA, but not tTS, into 3T3-L1 cells resulted in lipid accumulation. We conclude that expression of rtTA in adipose tissue causes metabolic syndrome in mice.
Subject(s)
Adipose Tissue/metabolism , Metabolic Syndrome/genetics , Trans-Activators/metabolism , Transcriptional Activation , 11-beta-Hydroxysteroid Dehydrogenase Type 1/genetics , 11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , 3T3-L1 Cells , Adipose Tissue/pathology , Animals , Blood Pressure , Chromosomes, Mammalian/genetics , Chromosomes, Mammalian/metabolism , DNA Fragmentation , Fatty Liver/genetics , Fatty Liver/metabolism , Fatty Liver/pathology , Gene Expression Profiling , Insulin Resistance , Lipid Metabolism , Male , Metabolic Syndrome/metabolism , Metabolic Syndrome/pathology , Mice , Mice, Transgenic , Muscles/metabolism , Muscles/pathology , Phenotype , Tetracycline/metabolism , Trans-Activators/genetics , Transfection , TransgenesABSTRACT
OBJECTIVE: Common genetic variants in a 58-kb region of chromosome 9p21, near the CDKN2A/CDKN2B tumor suppressor locus, are strongly associated with coronary artery disease. However, the underlying mechanism of action remains unknown. METHODS AND RESULTS: We previously reported a congenic mouse model harboring an atherosclerosis susceptibility locus and the region of homology with the human 9p21 locus. Microarray and transcript-specific expression analyses showed markedly decreased Cdkn2a expression, including both p16(INK4a) and p19(ARF), but not Cdkn2b (p15(INK4b)), in macrophages derived from congenic mice compared with controls. Atherosclerosis studies in subcongenic strains revealed genetic complexity and narrowed 1 locus to a small interval including Cdkn2a/b. Bone marrow (BM) transplantation studies implicated myeloid lineage cells as the culprit cell type, rather than resident vascular cells. To directly test the role of BM-derived Cdkn2a transcripts in atherogenesis and inflammatory cell proliferation, we performed a transplantation study using Cdkn2a(-/-) cells in the Ldlr(-/-) mouse model. Cdkn2a-deficient BM recipients exhibited accelerated atherosclerosis, increased Ly6C proinflammatory monocytes, and increased monocyte/macrophage proliferation compared with controls. CONCLUSION: These data provide a plausible mechanism for accelerated atherogenesis in susceptible congenic mice, involving decreased expression of Cdkn2a and increased proliferation of monocyte/macrophages, with possible relevance to the 9p21 human locus.
Subject(s)
Atherosclerosis/metabolism , Atherosclerosis/pathology , Cell Proliferation , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Macrophages/pathology , Monocytes/pathology , Animals , Atherosclerosis/genetics , Bone Marrow Transplantation , Cyclin-Dependent Kinase Inhibitor p16/genetics , Disease Models, Animal , Genes, p16 , Genetic Predisposition to Disease/genetics , Macrophages/metabolism , Mice , Mice, Congenic , Mice, Knockout , Monocytes/metabolism , Receptors, LDL/deficiency , Receptors, LDL/geneticsABSTRACT
Abemaciclib is an oral, selective cyclin-dependent kinase 4 & 6 inhibitor (CDK4 & 6i), approved for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) as monotherapy for endocrine refractory disease, and with endocrine therapy (ET) for initial treatment and after progression on ET. Abemaciclib has also shown clinical activity in combination with ET in patients with high risk early BC (EBC). Here, we examined the preclinical attributes of abemaciclib and other CDK4 & 6i using biochemical and cell-based assays. In vitro, abemaciclib preferentially inhibited CDK4 kinase activity versus CDK6, resulting in inhibition of cell proliferation in a panel of BC cell lines with higher average potency than palbociclib or ribociclib. Abemaciclib showed activity regardless of HER2 amplification and phosphatidylinositol 3-kinase (PI3KCA) gene mutation status. In human bone marrow progenitor cells, abemaciclib showed lower impact on myeloid maturation than other CDK4 & 6i when tested at unbound concentrations similar to those observed in clinical trials. Continuous abemaciclib treatment provided profound inhibition of cell proliferation, and triggered senescence and apoptosis. These preclinical results support the unique efficacy and safety profile of abemaciclib observed in clinical trials.
Subject(s)
Breast Neoplasms , Aminopyridines/pharmacology , Aminopyridines/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Benzimidazoles , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Proliferation , Cyclin-Dependent Kinase 4 , Cyclin-Dependent Kinase 6 , Female , Humans , Phosphatidylinositol 3-Kinases , Protein Kinase Inhibitors/therapeutic useABSTRACT
Prolonged activation of vascular endothelial growth factor receptor-2 (VEGFR-2) due to mis-regulation of the VEGF pathway induces aberrant blood vessel expansion, which supports growth and survival of solid tumors. Therapeutic interventions that inhibit the VEGFR-2 pathway have therefore become a mainstay of cancer treatment. Non-clinical studies have recently revealed that blockade of angiogenesis can modulate the tumor microenvironment and enhance the efficacy of concurrent immune therapies. Ramucirumab is an FDA-approved anti-angiogenic antibody that inhibits VEGFR-2 and is currently being evaluated in clinical studies in combination with anti-programmed cell death (PD-1) axis checkpoint inhibitors (pembrolizumab, durvalumab, or sintilimab) across several cancer types. The purpose of this study is to establish a mechanistic basis for the enhanced activity observed in the combined blockade of VEGFR-2 and PD-1-axis pathways. Pre-clinical studies were conducted in murine tumor models known to be responsive to anti-PD-1 axis therapy, using monoclonal antibodies that block mouse VEGFR-2 and programmed death-ligand 1 (PD-L1). Combination therapy resulted in enhanced anti-tumor activity compared to anti-PD-L1 monotherapy. VEGFR-2 blockade at early timepoints post-anti-PD-L1 therapy resulted in a dose-dependent and transient enhanced infiltration of T cells, and establishment of immunological memory. VEGFR-2 blockade at later timepoints resulted in enhancement of anti-PD-L1-driven immune cell infiltration. VEGFR-2 and PD-L1 monotherapies induced both unique and overlapping patterns of immune gene expression, and combination therapy resulted in an enhanced immune activation signature. Collectively, these results provide new and actionable insights into the mechanisms by which concurrent VEGFR-2 and PD-L1 antibody therapy leads to enhanced anti-tumor efficacy.
Subject(s)
Neoplasms , Vascular Endothelial Growth Factor Receptor-2 , Animals , B7-H1 Antigen/metabolism , Cell Line, Tumor , Mice , Neoplasms/therapy , Tumor Microenvironment , Vascular Endothelial Growth Factor AABSTRACT
Despite the biological and therapeutic relevance of CDK4/6 for the treatment of HR+, HER2- advanced breast cancer, the detailed mode of action of CDK4/6 inhibitors is not completely understood. Of particular interest, phosphorylation of CDK4 at T172 (pT172) is critical for generating the active conformation, yet no such crystal structure has been reported to date. We describe here the x-ray structure of active CDK4-cyclin D3 bound to the CDK4/6 inhibitor abemaciclib and discuss the key aspects of the catalytically-competent complex. Furthermore, the effect of CDK4/6 inhibitors on CDK4 T172 phosphorylation has not been explored, despite its role as a potential biomarker of CDK4/6 inhibitor response. We show mechanistically that CDK4/6i stabilize primed (pT172) CDK4-cyclin D complex and selectively displace p21 in responsive tumor cells. Stabilization of active CDK4-cyclin D1 complex can lead to pathway reactivation following alternate dosing regimen. Consequently, sustained binding of abemaciclib to CDK4 leads to potent cell cycle inhibition in breast cancer cell lines and prevents rebound activation of downstream signaling. Overall, our study provides key insights demonstrating that prolonged treatment with CDK4/6 inhibitors and composition of the CDK4/6-cyclin D complex are both critical determinants of abemaciclib efficacy, with implications for this class of anticancer therapy.
ABSTRACT
Increased serum apolipoprotein (apo)B and associated LDL levels are well-correlated with an increased risk of coronary disease. ApoEâ»/â» and low density lipoprotein receptor (LDLr)â»/â» mice have been extensively used for studies of coronary atherosclerosis. These animals show atherosclerotic lesions similar to those in humans, but their serum lipids are low in apoB-containing LDL particles. We describe the development of a new mouse model with a human-like lipid profile. Ldlr CETPâº/â» hemizygous mice carry a single copy of the human CETP transgene and a single copy of a LDL receptor mutation. To evaluate the apoB pathways in this mouse model, we used novel short-interfering RNAs (siRNA) formulated in lipid nanoparticles (LNP). ApoB siRNAs induced up to 95% reduction of liver ApoB mRNA and serum apoB protein, and a significant lowering of serum LDL in Ldlr CETPâº/â» mice. ApoB targeting is specific and dose-dependent, and it shows lipid-lowering effects for over three weeks. Although specific triglycerides (TG) were affected by ApoB mRNA knockdown (KD) and the total plasma lipid levels were decreased by 70%, the overall lipid distribution did not change. Results presented here demonstrate a new mouse model for investigating additional targets within the ApoB pathways using the siRNA modality.
Subject(s)
Apolipoproteins B/genetics , Atherosclerosis/genetics , Atherosclerosis/metabolism , Cholesterol Ester Transfer Proteins/genetics , Cholesterol, LDL/blood , Disease Models, Animal , Receptors, LDL/genetics , Animals , Apolipoproteins B/blood , Apolipoproteins E/blood , Apolipoproteins E/genetics , Atherosclerosis/pathology , Cell Line, Tumor , Cholesterol Ester Transfer Proteins/metabolism , Founder Effect , Gene Expression Profiling , Gene Knockdown Techniques , Hemizygote , Humans , Lipid Metabolism/genetics , Liposomes/metabolism , Liver/drug effects , Liver/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nanoparticles/administration & dosage , RNA, Messenger/analysis , RNA, Messenger/biosynthesis , RNA, Small Interfering/metabolism , RNA, Small Interfering/pharmacology , Receptors, LDL/metabolism , Triglycerides/bloodABSTRACT
The purinergic receptor P2Y(13) has been shown to play a role in the uptake of holo-HDL particles in in vitro hepatocyte experiments. In order to determine the role of P2Y(13) in lipoprotein metabolism in vivo, we ablated the expression of this gene in mice. Here we show that P2Y(13) knockout mice have lower fecal concentrations of neutral sterols (-27%±2.1% in males) as well as small decreases in plasma HDL (-13.1%±3.2% in males; -17.5%±4.0% in females) levels. In addition, significant decreases were detected in serum levels of fatty acids and glycerol in female P2Y(13) knockout mice. Hepatic mRNA profiling analyses showed increased expression of SREBP-regulated cholesterol and fatty acid biosynthesis genes, while fatty acid ß-oxidation genes were significantly decreased. Liver gene signatures also identified changes in PPARα-regulated transcript levels. With the exception of a small increase in bone area, P2Y(13) knockout mice do not show any additional major abnormalities, and display normal body weight, fat mass and lean body mass. No changes in insulin sensitivity and oral glucose tolerance could be detected. Taken together, our experiments assess a role for the purinergic receptor P2Y(13) in the regulation of lipoprotein metabolism and demonstrate that modulating its activity could be of benefit to the treatment of dyslipidemia in people.
Subject(s)
Lipoproteins/metabolism , Receptors, Purinergic P2/physiology , Animals , Female , Gene Expression Profiling , Liver/metabolism , Male , Mice , Mice, Knockout , RNA, Messenger/genetics , Receptors, Purinergic P2/geneticsABSTRACT
Forkhead box class O (FoxO) transcription factors are key regulators of growth, metabolism, life span, and stress resistance. FoxOs integrate signals from different pathways and guide the cellular response to varying energy and stress conditions. FoxOs are modulated by several signaling pathways, e.g., the insulin-TOR signaling pathway and the stress induced JNK signaling pathway. Here, we report a genome wide RNAi screen of kinases and phosphatases aiming to find regulators of dFoxO activity in Drosophila S2 cells. By using a combination of transcriptional activity and localization assays we identified several enzymes that modulate dFoxO transcriptional activity, intracellular localization and/or protein stability. Importantly, several currently known dFoxO regulators were found in the screening, confirming the validity of our approach. In addition, several interesting new regulators were identified, including protein kinase C and glycogen synthase kinase 3beta, two proteins with important roles in insulin signaling. Furthermore, several mammalian orthologs of the proteins identified in Drosophila also regulate FOXO activity in mammalian cells. Our results contribute to a comprehensive understanding of FoxO regulatory processes.
Subject(s)
Forkhead Transcription Factors/metabolism , Phosphoric Monoester Hydrolases/metabolism , Protein Kinases/metabolism , RNA Interference , Animals , Cell Line , Cell Nucleus/metabolism , Drosophila/genetics , Drosophila/metabolism , Gene Library , Genome, Insect , Glycogen Synthase Kinase 3/genetics , Glycogen Synthase Kinase 3/metabolism , Glycogen Synthase Kinase 3 beta , Humans , Phosphoric Monoester Hydrolases/genetics , Protein Kinase C/genetics , Protein Kinase C/metabolism , Protein Kinases/genetics , Transcription, GeneticABSTRACT
INTRODUCTION: Sintilimab plus chemotherapy significantly prolonged progression-free survival (PFS) compared with chemotherapy alone in nonsquamous NSCLC in the ORIENT-11 study. Updated overall survival (OS) and PFS data and corresponding biomarker analyses are reported here. METHODS: In this study, a total of 397 patients with previously untreated, locally advanced or metastatic nonsquamous NSCLC were assigned to sintilimab plus chemotherapy combination treatment (combo) group or placebo plus chemotherapy treatment group. The patients were stratified by programmed death-ligand 1 (PD-L1) expression levels. Immune signature profiles from tumor RNA sequencing and PD-L1 immunohistochemistry were correlated with clinical outcome to identify predictive biomarkers. RESULTS: As of January 2021, with median follow-up of 22.9 months, median OS was significantly improved in the combo group compared with the placebo plus chemotherapy treatment group (not reached versus 16.8 mo; hazard ratio [HR] = 0.60, 95% confidence interval [CI]: 0.45-0.79, p = 0.0003). High or medium immune cell infiltration was strongly associated with improved PFS in the combo group, in contrast to absent or low immune cell infiltration, which suggests that chemotherapy could not prime "immune deserts" to obtain benefit from programmed cell death protein-1 inhibition. In particular, high major histocompatibility complex (MHC) class II presentation pathway expression was significantly correlated with prolonged PFS (HR = 0.32, 95% CI: 0.19-0.54, p < 0.0001) and OS (HR = 0.36, 95% CI: 0.20-0.64, p = 0.0005) in the combo group. Importantly, patients with low or absent PD-L1 but high MHC class II expression could still benefit from the combo treatment. In contrast, MHC class I antigen presentation pathway was less relevant in this combination setting. CONCLUSIONS: The addition of sintilimab to chemotherapy resulted to significantly longer OS in nonsquamous NSCLC. Expression of MHC class II antigen presentation pathway could identify patients benefiting most from this combination.
Subject(s)
Lung Neoplasms , Platinum , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers , Humans , Lung Neoplasms/drug therapy , Pemetrexed/therapeutic use , Platinum/therapeutic useABSTRACT
Hypertension is a condition with major cardiovascular and renal complications, affecting nearly a billion patients worldwide. Few validated gene targets are available for pharmacological intervention, so there is a need to identify new biological pathways regulating blood pressure and containing novel targets for treatment. The genetically hypertensive "blood pressure high" (BPH), normotensive "blood pressure normal" (BPN), and hypotensive "blood pressure low" (BPL) inbred mouse strains are an ideal system to study differences in gene expression patterns that may represent such biological pathways. We profiled gene expression in liver, heart, kidney, and aorta from BPH, BPN, and BPL mice and determined which biological processes are enriched in observed organ-specific signatures. As a result, we identified multiple biological pathways linked to blood pressure phenotype that could serve as a source of candidate genes causal for hypertension. To distinguish in the kidney signature genes whose differential expression pattern may cause changes in blood pressure from those genes whose differential expression pattern results from changes in blood pressure, we integrated phenotype-associated genes into Genetic Bayesian networks. The integration of data from gene expression profiling and genetics networks is a valuable approach to identify novel potential targets for the pharmacological treatment of hypertension.