Despite the success of tyrosine kinase-based cancer therapeutics, for most solid tumors the tyrosine kinases that drive disease remain unknown, limiting our ability to identify drug targets and predict response. Here we present the first large-scale survey of tyrosine kinase activity in lung cancer. Using a phosphoproteomic approach, we characterize tyrosine kinase signaling across 41 non-small cell lung cancer (NSCLC) cell lines and over 150 NSCLC tumors. Profiles of phosphotyrosine signaling are generated and analyzed to identify known oncogenic kinases such as EGFR and c-Met as well as novel ALK and ROS fusion proteins. Other activated tyrosine kinases such as PDGFRalpha and DDR1 not previously implicated in the genesis of NSCLC are also identified. By focusing on activated cell circuitry, the approach outlined here provides insight into cancer biology not available at the chromosomal and transcriptional levels and can be applied broadly across all human cancers.
With the goal of devising a non-invasive cell therapy for cardiac repair that may be well tolerated by patients with myocardial infarction (MI), this study evaluated the efficacy of intravenous infusion of genetically modified mesenchymal stem cells (MSCs) overexpressing CXC chemokine receptor 4 (CXCR4). CXCR4 is the cognate receptor for stromal-derived factor-1 (SDF-1), a chemokine required for homing of progenitor cells to ischemic tissues. In this study, retrovirally transduced MSCs constitutively expressing CXCR4 (CXCR4-MSCs) were delivered intravenously 24 hours after coronary occlusion/reperfusion in rats. When compared with untransduced MSCs, CXCR4-MSCs homed in toward the infarct region of the myocardium in greater numbers. In the CXCR4-MSC-treated animals, echocardiographic imaging 30 days after MI showed a decrease in anterior wall thinning and good preservation of left ventricular (LV) chamber dimensions, whereas the animals treated with saline or unmodified MSCs showed significant remodeling. Histochemical analysis showed a decrease in collagen I/III ratio in the infarcted wall of CXCR4-MSC-treated animals, thereby suggesting improved chamber compliance. Assessment revealed post-MI recovery of LV function in the CXCR4-MSC-treated animals, whereas LV function remained depressed in the saline and MSC-treated animals. In summary, intravenous delivery of genetically modified MSCs expressing CXCR4 may be a useful, non-invasive, and safe therapeutic strategy for post-infarction myocardial repair.
Purpose: To deepen our understanding of mutant ROS1 expression, localization, and frequency in nonsmall cell lung cancer (NSCLC), we developed a highly specific and sensitive immunohistochemistry (IHC)-based assay that is useful for the detection of wild-type and mutant ROS1.Experimental Design: We analyzed 556 tumors with the ROS1 D4D6 rabbit monoclonal antibody IHC assay to assess ROS1 expression levels and localization. A subset of tumors was analyzed by FISH to determine the percentage of these tumors harboring ROS1 translocations. Using specific and sensitive IHC assays, we analyzed the expression of anaplastic lymphoma kinase (ALK), EGFR L858R, and EGFR E746-A750del mutations in a subset of lung tumors, including those expressing ROS1.Results: In our NSCLC cohort of Chinese patients, we identified 9 (1.6%) tumors expressing ROS1 and 22 (4.0%) tumors expressing ALK. FISH identified tumors with ALK or ROS1 rearrangements, and IHC alone was capable of detecting all cases with ALK and ROS1 rearrangements. ROS1 fusion partners were determined by reverse transcriptase PCR identifying CD74-ROS1, SLC34A2-ROS1, and FIG-ROS1 fusions. Some of the ALK and ROS1 rearranged tumors may also harbor coexisting EGFR mutations.Conclusions: NSCLC tumors with ROS1 rearrangements are uncommon in the Chinese population and represent a distinct entity of carcinomas. The ROS1 IHC assay described here is a valuable tool for identifying patients expressing mutant ROS1 and could be routinely applied in clinical practice to detect lung cancers that may be responsive to targeted therapies.
Purpose: Activating mutations within the tyrosine kinase domain of epidermal growth factor receptor (EGFR) are found in approximately 10% to 20% of non^small-cell lung cancer (NSCLC) patients and are associated with response to EGFR inhibitors. The most common NSCLCassociated EGFR mutations are deletions in exon 19 and L858R mutation in exon 21, together accounting for 90% of EGFR mutations. To develop a simple, sensitive, and reliable clinical assay for the identification of EGFR mutations in NSCLC patients, we generated mutation-specific rabbit monoclonal antibodies against each of these two most common EGFR mutations and aimed to evaluate the detection of EGFR mutations in NSCLC patients by immunohistochemistry. Experimental Design:We tested mutation-specific antibodies byWestern blot, immunofluorescence, and immunohistochemistry. In addition, we stained 40 EGFR genotyped NSCLC tumor samples by immunohistochemistry with these antibodies. Finally, with a panel of four antibodies, we screened a large set of NSCLC patient samples with unknown genotype and confirmed the immunohistochemistry results by DNA sequencing. Results: These two antibodies specifically detect the corresponding mutant form of EGFR by Western blotting, immunofluorescence, and immunohistochemistry. Screening a panel of 340 paraffin-embedded NSCLC tumor samples with these antibodies showed that the sensitivity of the immunohistochemistry assay is 92%, with a specificity of 99% as compared with direct and mass spectrometry^based DNA sequencing. Conclusions: This simple assay for detection of EGFR mutations in diagnostic human tissues provides a rapid, sensitive, specific, and cost-effective method to identify lung cancer patients responsive to EGFR-based therapies.Lung cancer is a major cause of cancer-related mortality worldwide and is expected to remain a major health problem for the foreseeable future. Lung cancer is broadly divided into small-cell lung cancer (20% of lung cancers) and non -smallcell lung cancer (NSCLC; 80% of lung cancers). Somatic mutations in the epidermal growth factor receptor (EGFR) gene are found in a subset of NSCLC adenocarcinomas and are associated with sensitivity to the small-molecule EGFR tyrosine kinase inhibitors gefitinib (1, 2) and erlotinib (3). Different EGFR mutations have been reported, but the most common NSCLC-associated EGFR mutations are in-frame deletions in exon 19 (E746_A750del) and the point mutation replacing leucine with arginine at codon 858 in exon 21 (L858R; refs. 3 -5). These two mutations represent 85% to 90% of EGFR mutations in NSCLC patients. Data from clinical research have confirmed that patients with these mutations are highly responsive to EGFR inhibitors including gefitinib and erlotinib (5 -8).Based on these clinical findings, EGFR mutational analysis in lung adenocarcinoma may now be used to guide treatment decisions and to enroll patients in specific arms of clinical trials. Direct DNA sequencing of PCR-amplified genomic DNA has been developed to detect EGFR mutations i...
Cholangiocarcinoma, also known as bile duct cancer, is the second most common primary hepatic carcinoma with a median survival of less than 2 years. The molecular mechanisms underlying the development of this disease are not clear. To survey activated tyrosine kinases signaling in cholangiocarcinoma, we employed immunoaffinity profiling coupled to mass spectrometry and identified DDR1, EPHA2, EGFR, and ROS tyrosine kinases, along with over 1,000 tyrosine phosphorylation sites from about 750 different proteins in primary cholangiocarcinoma patients. Furthermore, we confirmed the presence of ROS kinase fusions in 8.7% (2 out of 23) of cholangiocarcinoma patients. Expression of the ROS fusions in 3T3 cells confers transforming ability both in vitro and in vivo, and is responsive to its kinase inhibitor. Our data demonstrate that ROS kinase is a promising candidate for a therapeutic target and for a diagnostic molecular marker in cholangiocarcinoma. The identification of ROS tyrosine kinase fusions in cholangiocarcinoma, along with the presence of other ROS kinase fusions in lung cancer and glioblastoma, suggests that a more broadly based screen for activated ROS kinase in cancer is warranted.
Previous studies suggested a possible gut microbiota dysbiosis in chronic heart failure (CHF). However, direct evidence was lacking. In this study, we investigated the composition and metabolic patterns of gut microbiota in CHF patients to provide direct evidence and comprehensive understanding of gut microbiota dysbiosis in CHF. We enrolled 53 CHF patients and 41 controls. Metagenomic analyses of faecal samples and metabolomic analyses of faecal and plasma samples were then performed. We found that the composition of gut microbiota in CHF was significantly different from controls. Faecalibacterium prausnitzii decrease and Ruminococcus gnavus increase were the essential characteristics in CHF patients’ gut microbiota. We also observed an imbalance of gut microbes involved in the metabolism of protective metabolites such as butyrate and harmful metabolites such as trimethylamine N-oxide in CHF patients. Metabolic features of both faecal and plasma samples from CHF patients also significantly changed. Moreover, alterations in faecal and plasma metabolic patterns correlated with gut microbiota dysbiosis in CHF. Taken together, we found that CHF was associated with distinct gut microbiota dysbiosis and pinpointed the specific core bacteria imbalance in CHF, along with correlations between changes in certain metabolites and gut microbes.
BackgroundPost-infarction cardiovascular remodeling and heart failure are the leading cause of myocardial infarction (MI)-driven death during the past decades. Experimental observations have involved intestinal microbiota in the susceptibility to MI in mice; however, in humans, identifying whether translocation of gut bacteria to systemic circulation contributes to cardiovascular events post-MI remains a major challenge.ResultsHere, we carried out a metagenomic analysis to characterize the systemic bacteria in a cohort of 49 healthy control individuals, 50 stable coronary heart disease (CHD) subjects, and 100 ST-segment elevation myocardial infarction (STEMI) patients. We report for the first time higher microbial richness and diversity in the systemic microbiome of STEMI patients. More than 12% of post-STEMI blood bacteria were dominated by intestinal microbiota (Lactobacillus, Bacteroides, and Streptococcus). The significantly increased product of gut bacterial translocation (LPS and d-lactate) was correlated with systemic inflammation and predicted adverse cardiovascular events. Following experimental MI, compromised left ventricle (LV) function and intestinal hypoperfusion drove gut permeability elevation through tight junction protein suppression and intestinal mucosal injury. Upon abrogation of gut bacterial translocation by antibiotic treatment, both systemic inflammation and cardiomyocyte injury in MI mice were alleviated.ConclusionsOur results provide the first evidence that cardiovascular outcomes post-MI are driven by intestinal microbiota translocation into systemic circulation. New therapeutic strategies targeting to protect the gut barrier and eliminate gut bacteria translocation may reduce or even prevent cardiovascular events post-MI.Electronic supplementary materialThe online version of this article (10.1186/s40168-018-0441-4) contains supplementary material, which is available to authorized users.
Rationale: Clinical benefits of reperfusion after myocardial infarction are offset by maladaptive innate immune cell function, and therapeutic interventions are lacking. Objective : We sought to test the significance of phagocytic clearance by resident and recruited phagocytes after myocardial ischemia reperfusion. Methods and Results: In humans, we discovered that clinical reperfusion after myocardial infarction led to significant elevation of the soluble form of MerTK (myeloid-epithelial-reproductive tyrosine kinase; ie, soluble MER), a critical biomarker of compromised phagocytosis by innate macrophages. In reperfused mice, macrophage Mertk deficiency led to decreased cardiac wound debridement, increased infarct size, and depressed cardiac function, newly implicating MerTK in cardiac repair after myocardial ischemia reperfusion. More notably, Mertk(CR ) mice, which are resistant to cleavage, showed significantly reduced infarct sizes and improved systolic function. In contrast to other cardiac phagocyte subsets, resident cardiac MHCII LO CCR2 − (major histocompatibility complex II/C-C motif chemokine receptor type 2) macrophages expressed higher levels of MerTK and, when exposed to apoptotic cells, secreted proreparative cytokines, including transforming growth factor-β. Mertk deficiency compromised the accumulation of MHCII LO phagocytes, and this was rescued in Mertk(CR ) mice. Interestingly, blockade of CCR2-dependent monocyte infiltration into the heart reduced soluble MER levels post-ischemia reperfusion. Conclusions: Our data implicate monocyte-induced MerTK cleavage on proreparative MHCII LO cardiac macrophages as a novel contributor and therapeutic target of reperfusion injury.
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