Dissecting the treatment-naive ecosystem of human melanoma brain metastasis

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The increased expression and aberrant methylation of SHC1 in non–small cell lung cancer: Integrative analysis of clinical and bioinformatics databases

Despite the previous evidence showing that SHC adaptor protein 1 (SHC1) could encode three distinct isoforms (p46SHC, p52SHC and p66SHC) that function in different activities such as regulating life span and Ras activation, the precise underlying role of SHC1 in lung cancer also remains obscure. In this study, we firstly found that SHC1 expression was up-regulated both in lung adenocarcinoma (LUAD) and in lung squamous cell carcinoma (LUSC) tissues. Furthermore, compared to patients with lower SHC1 expression, LUAD patients with higher expression of SHC1 had poorer overall survival (OS). Moreover, higher expression of SHC1 was also associated with worse OS in patients with stages 1 and 2 but not stage 3 lung cancer. Significantly, the analysis showed that SHC1 methylation level was associated with OS in lung cancer patients. It seemed that the methylation level at specific probes within SHC1 showed negative correlations with SHC1 expression both in LUAD and in LUSC tissues. The LUAD and LUSC patients with hypermethylated SHC1 at cg12473916 and cg19356022 probes had a longer OS. Therefore, it is reasonable to conclude that SHC1 has a potential clinical significance in LUAD and LUSC patients.     

Impact of iterative reconstructions on image quality and detectability of focal liver lesions in low-energy monochromatic images

PurposeTo assess the impact of iterative reconstructions on image quality and detectability of focal liver lesions in low-energy monochromatic images from a Fast kV-Switching Dual Energy CT (KVSCT) platform.MethodsAcquisitions on an image-quality phantom were performed using a KVSCT for three dose levels (CTDI_vol:12.72/10.76/8.79 mGy). Raw data were reconstructed for five energy levels (40/50/60/70/80 keV) using Filtered Back Projection (FBP) and four levels of ASIR (ASIR30/ASIR50/ASIR70/ASIR100). Noise power spectrum (NPS) and task-based transfer function (TTF) were measured before computing a Detectability index (d′) to model the detection task of liver metastasis (LM) and hepatocellular carcinoma (HCC) as function of keV.ResultsFrom 40 to 70 keV, noise-magnitude was reduced on average by −68% ± 1% with FBP; −61% ± 3% with ASIR50 and −52% ± 6% with ASIR100. The mean spatial frequency of the NPS decreased when the energy level decreased and the iterative level increased. TTF values at 50% decreased as the energy level increased and as the percentage of ASIR increased. The detectability of both lesions increased with increasing dose level and percentage of ASIR. For the LM, d′ peaked at 70 keV for all reconstruction types, except for ASIR70 at 12.72 mGy and ASIR100, where d' peaked at 50 keV. For HCC, d’ peaked at 60 keV for FBP and ASIR30 but peaked at 50 keV for ASIR50, ASIR70 and ASIR100.ConclusionsUsing percentage of ASIR above 50% at low-energy monochromatic images could limit the increase of noise-magnitude, benefit from spatial resolution improvement and hence enhance detectability of subtle low contrast focal liver lesions such as HCC.     

Catalpol inhibits TGF-β1-induced epithelial-mesenchymal transition in human non–small-cell lung cancer cells through the inactivation of Smad2/3 and NF-κB signaling pathways

Catalpol, one of the main active ingredients isolated from Rehmannia glutinosa, was reported to possess anticancer activity. However, the role of catalpol in transforming growth factor β1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) in human non–small-cell lung cancer (NSCLC) cells has not been elucidated. The objective of this study was to investigate the effect of catalpol on EMT in human NSCLC cells. Our results showed that catalpol significantly inhibited the TGF-β1-induced cell migration and invasion of A549 cells, as well as repressed matrix metalloproteinase (MMP)2 and MMP9 expression induced by TGF-β1 in A549 cells. In addition, catalpol markedly repressed the EMT process in A549 cells in response to TGF-β1. Furthermore, catalpol prevented the activation of Smad2/3 and nuclear factor κB (NF-κB) signaling pathways induced by TGF-β1 in A549 cells. In conclusion, these findings indicated that catalpol inhibits TGF-β1-induced EMT in human NSCLC cells through the inactivation of Smad2/3 and NF-κB signaling pathways. Thus, catalpol may be a promising agent for the treatment of NSCLC.     

Genetic ablation of caveolin-2 sensitizes mice to bleomycin-induced injury

Caveolar domains act as platforms for the organization of molecular complexes involved in signal transduction. Caveolin proteins, the principal structural components of caveolae, have been involved in many cellular processes. Caveolin-1 (Cav-1) and caveolin-2 (Cav-2) are highly expressed in the lung. Cav-1-deficient mice (Cav-1^−/−) and Cav-2-deficient mice (Cav-2^−/−) exhibit severe lung dysfunction attributed to a lack of Cav-2 expression. Recently, Cav-1 has been shown to regulate lung fibrosis in different models. Here, we show that Cav-2 is also involved in modulation of the fibrotic response, but through distinct mechanisms. Treatment of wild-type mice with the pulmonary fibrosis-inducer bleomycin reduced the expression of Cav-2 and its phosphorylation at tyrosine 19. Importantly, Cav-2^−/− mice, but not Cav-1^−/− mice, were more sensitive to bleomycin-induced lung injury in comparison to wild-type mice. Bleomycin-induced lung injury was characterized by alveolar thickening, increase in cell density, and extracellular matrix deposition. The lung injury observed in bleomycin-treated Cav-2^−/− mice was not associated with alterations in the TGF-β signaling pathway and/or in the ability to produce collagen. However, apoptosis and proliferation were more prominent in lungs of bleomycin-treated Cav-2^−/− mice. Since Cav-1^−/− mice also lack Cav-2 expression and show a different outcome after bleomycin treatment, we conclude that Cav-1 and Cav-2 have distinct roles in bleomycin induced-lung fibrosis, and that the balance of both proteins determines the development of the fibrotic process.     

Esophageal cancer lymph node metastasis–associated gene signature optimizes overall survival prediction of esophageal cancer

Esophageal cancer (EC) is characteristic of early regional lymph node metastasis (LNM) and most patients with metastasis have a poor prognosis. However, the current diagnostic techniques do not enable precise differentiation of EC LNM, prognostic stratification, and individual survival estimation. To identify potential molecular biomarkers for EC patients with LNM, we explored differently expressed genes in The Cancer Genome Atlas database between 77 non-LNM cases and 88 LNM cases by limma package R. Then, according to univariate and multivariate Cox regression analyses, we constructed an 8-messenger RNA (mRNA) prognostic signature model, which could predict the outcome in a more exact way. The area under the curve of the risk score is significantly higher than other clinical information, indicating that the 8-mRNA–based risk score is a good indicator for prognosis. Then, combined with other individual risk factors, such as age, sex, T stage, M stage, etc, we could precisely calculate the individual 1-, 3-, and 5-year survival rates. The Gene Set Enrichment Analysis, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes analysis indicate that the risk model is mainly associated with cancer-related pathways, such as cell division, cellular meiosis, and cell cycle regulation. In summary, the 8-mRNA–based risk score model that we developed successfully predicts the survival of EC. It is independent of clinical information and performing better than other clinical information for prognosis.     

The thiazole derivative CPTH6 impairs autophagy

We have previously demonstrated that the thiazole derivative 3-methylcyclopentylidene-[4-(4′-chlorophenyl)thiazol-2-yl]hydrazone (CPTH6) induces apoptosis and cell cycle arrest in human leukemia cells. The aim of this study was to evaluate whether CPTH6 is able to affect autophagy. By using several human tumor cell lines with different origins we demonstrated that CPTH6 treatment induced, in a dose-dependent manner, a significant increase in autophagic features, as imaged by electron microscopy, immunoblotting analysis of membrane-bound form of microtubule-associated protein 1 light chain 3 (LC3B-II) levels and by appearance of typical LC3B-II-associated autophagosomal puncta. To gain insights into the molecular mechanisms of elevated markers of autophagy induced by CPTH6 treatment, we silenced the expression of several proteins acting at different steps of autophagy. We found that the effect of CPTH6 on autophagy developed through a noncanonical mechanism that did not require beclin-1-dependent nucleation, but involved Atg-7-mediated elongation of autophagosomal membranes. Strikingly, a combined treatment of CPTH6 with late-stage autophagy inhibitors, such as chloroquine and bafilomycin A1, demonstrates that under basal condition CPTH6 reduces autophagosome turnover through an impairment of their degradation pathway, rather than enhancing autophagosome formation, as confirmed by immunofluorescence experiments. According to these results, CPTH6-induced enhancement of autophagy substrate p62 and NBR1 protein levels confirms a blockage of autophagic cargo degradation. In addition, CPTH6 inhibited autophagosome maturation and compounds having high structural similarities with CPTH6 produced similar effects on the autophagic pathway. Finally, the evidence that CPTH6 treatment decreased α-tubulin acetylation and failed to increase autophagic markers in cells in which acetyltransferase ATAT1 expression was silenced indicates a possible role of α-tubulin acetylation in CPTH6-induced alteration in autophagy. Overall, CPTH6 could be a valuable agent for the treatment of cancer and should be further studied as a possible antineoplastic agent.     

Matrix metalloproteinase expression in primary lung fibroblasts of layer type chickens

Abstract

We attempted to determine the growth characteristics of cultured lung fibroblasts of layer type chickens and to investigate presence of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in these cells in vitro. Lung fibroblasts were isolated, characterized and subcultured from one-day-old layer type chicken lungs. Two different methods, explant culture and enzymatic techniques, were used for culturing and the results were compared. The presence of MMP-2 and TIMP-1 was shown in cultured fibroblasts by immunocytochemical staining, immune blotting and zymography methods. Immune expressions of neither MMP-9 nor TIMP-2 enzymes could be detected.