Colorectal cancer (CRC) is the second leading cause of cancer‐related deaths worldwide. However, a biomarker for a sensitive and simple diagnostic test and highly effective target therapy of CRC is still clinically unavailable. This study is to investigate the evidence and significance of plasma GPC1 positive exosomes as a biomarker of CRC. Results showed that GPC1⁺ exosomes were successfully isolated from tissues and plasma. The percentage of GPC1⁺ exosomes and the GPC1 protein expression in exosomes from tumour tissues and plasma of CRC patients before surgical treatment was significantly elevated compared to that in the peritumoural tissues and the plasma of healthy controls. miR‐96‐5p and miR‐149 expression in tumour tissues and plasma of CRC patients as well as in the GPC1⁺ exosomes from CRC patients were significantly decreased compared to that in the peritumoural tissues and the plasma of healthy controls. Two months after surgical treatment, levels of all tested markers significantly normalized. Overexpression of miR‐96‐5p and miR‐149 significantly decreased GPC1 expression in HT‐29 and HCT‐116 cells, xenograft tumours, plasma in mice bearing HT‐29 and HCT‐116 tumours, and the secretion of GPC1⁺ exosomes from the HT‐29 and HCT‐116 cells and xenograft tumours. Overexpression of miR‐96‐5p and miR‐149 significantly decreased cell viability and increased cell apoptosis in HT‐29 and HCT‐116 cells, and inhibited the growth of xenograft HT‐29 and HCT‐116 tumours. In conclusion, the increased plasma GPC1⁺ exosomes and reduced plasma miR‐96‐5p and miR‐149 expression are specific markers for the diagnosis of CRC and targets for the therapy of CRC.

Polypyrimidine tract-binding protein 1 (PTBP1) plays an essential role in splicing and is expressed in almost all cell types in humans, unlike the other proteins of the PTBP family. PTBP1 mediates...

Background: Nasopharyngeal carcinoma (NPC) is a common malignant tumor in southern China and Southeast Asia, but its molecular mechanisms of pathogenesis are poorly understood. Our previous work has demonstrated that BCAT1 mRNA is over expressed in NPC and knocking down its expression in 5-8F NPC cell line can potently inhibit cell cycle progression and cell proliferation. However, the mechanism of BCAT1 up-regulation and its functional role in NPC development remain to be elucidated yet. Methods: Immunohistochemistry (IHC) method was utilized to detect the expression of BCAT1 protein in NPC at different pathological stages. The roles of gene mutation, DNA amplification and transcription factor c-Myc in regulating BCAT1 expression were analyzed using PCR-sequencing, quantitative polymerase chain reaction (qPCR), IHC, ChIP and luciferase reporter system, respectively. The functions of BCAT1 in colony formation, cell migration and invasion properties were evaluated by RNA interference (RNAi). Results: The positive rates of BCAT1 protein expression in normal epithelia, low-to-moderate grade atypical hyperplasia tissues, high-grade atypical hyperplasia tissues and NPC tissues were 23.6% (17/72), 75% (18/24 ), 88.9% (8/9) and 88.8% (71/80), respectively. Only one SNP site in exon1 was detected, and 42.4% (12/28) of the NPC tissues displayed the amplification of microsatellite loci in BCAT1. C-Myc could directly bind to the c-Myc binding site in promoter region of BCAT1 and up-regulate its expression. The mRNA and protein of c-Myc and BCAT1 were co-expressed in 53.6% (15/28) and 59.1% (13/22) of NPC tissues, respectively, and BCAT1 mRNA expression was also down-regulated in c-Myc knockdown cell lines. In addition, BCAT1 knockdown cells demonstrated reduced proliferation and decreased cell migration and invasion abilities. Conclusions: Our study indicates that gene amplification and c-Myc up-regulation are responsible for BCAT1 overexpression in primary NPC, and overexpression of BCAT1 induces cell proliferation, migration and invasion. The results suggest that BCAT1 may be a novel molecular target for the diagnosis and treatment of NPC.

Background: Gliomas account for the majority of fatal primary brain tumors, and there is much room for research in the underlying pathogenesis, the multistep progression of glioma, and how to improve survival. In our study, we aimed to identify potential biomarkers or therapeutic targets of glioma and study the mechanism underlying the tumor progression.Methods: We downloaded the microarray datasets (GSE43378 and GSE7696) from the Gene Expression Omnibus (GEO) database. Then, we used weighted gene co-expression network analysis (WGCNA) to screen potential biomarkers or therapeutic targets related to the tumor progression. ESTIMATE (Estimation of STromal and Immune cells in MAlignant Tumors using Expression data) algorithm and TIMER (Tumor Immune Estimation Resource) database were used to analyze the correlation between the selected genes and the tumor microenvironment. Real-time reverse transcription polymerase chain reaction was used to measure the selected gene. Transwell and wound healing assays were used to measure the cell migration and invasion capacity. Western blotting was used to test the expression of epithelial-mesenchymal transition (EMT) related markers.Results: We identified specific module genes that were positively correlated with the WHO grade but negatively correlated with OS of glioma. Importantly, we identified that 6 collagen genes (COL1A1, COL1A2, COL3A1, COL4A1, COL4A2, and COL5A2) could regulate the immunosuppressive microenvironment of glioma. Moreover, we found that these collagen genes were significantly involved in the EMT process of glioma. Finally, taking COL3A1 as a further research object, the results showed that knockdown of COL3A1 significantly inhibited the migration, invasion, and EMT process of SHG44 and A172 cells.Conclusions: In summary, our study demonstrated that collagen genes play an important role in regulating the immunosuppressive microenvironment and EMT process of glioma and could serve as potential therapeutic targets for glioma management.

Nasopharyngeal carcinoma (NPC) is a malignant epithelial carcinoma of the head and neck region which mainly distributes in southern China and Southeast Asia and has a crucial association with the Epstein–Barr virus. Based on epidemiological data, both incidence and mortality of NPC have significantly declined in recent decades grounded on the improvement of living standard and medical level in an endemic region, in particular, with the clinical use of individualized chemotherapy and intensity-modulated radiotherapy (IMRT) which profoundly contributes to the cure rate of NPC patients. To tackle the challenges including local recurrence and distant metastasis in the current NPC treatment, we discussed the implication of using targeted therapy against critical molecules in various signal pathways, and how they synergize with chemoradiotherapy in the NPC treatment. Combination treatment including targeted therapy and IMRT or concurrent chemoradiotherapy is presumably to be future options, which may reduce radiation or chemotherapy toxicities and open new avenues for the improvement of the expected functional outcome for patients with advanced NPC.