Hsa_circ_0026628 promotes the development of colorectal cancer by targeting SP1 to activate the Wnt/ß-catenin pathway.

Circular RNAs (circRNAs) have been reported to play crucial roles in the progression of various cancers, including colorectal cancer (CRC). SP1 (Sp1 transcription factor) is a well-recognized oncogene in CRC and is deemed to trigger the Wnt/ß-catenin pathway. The present study was designed to investigate the role of circRNAs which shared the same pre-mRNA with SP1 in CRC cells. We identified that hsa_circ_0026628 (circ_0026628), a circular RNA that originated from SP1 pre-mRNA, was upregulated in CRC cells. Sanger sequencing and agarose gel electrophoresis verified the circular characteristic of circ_0026628. Functional assays including CCK-8, colony formation, transwell, immunofluorescence staining, and sphere formation assay revealed the function of circ_0026628. RNA pull-down and mass spectrometry disclosed the proteins interacting with circ_0026628. Mechanistic assays including RIP, RNA pull-down, CoIP, ChIP, and luciferase reporter assays demonstrated the interplays between molecules. The results depicted that circ_0026628 functioned as a contributor to CRC cell proliferation, migration, EMT, and stemness. Mechanistically, circ_0026628 served as the endogenous sponge of miR-346 and FUS to elevate SP1 expression at the post-transcriptional level, thus strengthening the interaction between SP1 and ß-catenin to activate the Wnt/ß-catenin pathway. In turn, the downstream gene of Wnt/ß-catenin signaling, SOX2 (SRY-box transcription factor 2), transcriptionally activated SP1 and therefore boosted circ_0026628 level. On the whole, SOX2-induced circ_0026628 sponged miR-346 and recruited FUS protein to augment SP1, triggering the downstream Wnt/ß-catenin pathway to facilitate CRC progression.

FLNA promotes chemoresistance of colorectal cancer through inducing epithelial-mesenchymal transition and smad2 signaling pathway.

Chemoresistance is a leading cause of tumor relapse and treatment failure in colorectal cancer (CRC) patients and is correlated with epithelial-mesenchymal transition (EMT). This study was aimed to explore the mechanism of EMT in chemoresistant CRC. Bioinformatic method was used to screen differentially expressed genes between 5-FU sensitive and resistant CRC cells. Immunohistochemistry staining was utilized to analyze the expression of FLNA in CRC tissues. The roles of FLNA in chemoresistance were validated via loss-of-function and gain-of-function experiments in vitro and in an orthotopic CRC animal model. The regulation of c-Met signaling by FLNA was explored via Co-Immunoprecipitation and luciferase reporter assays. Our results suggested FLNA directly regulated the metastasis and EMT of chemoresistant CRC cells. Moreover, c-Met-AKT mediated ser2152 phosphorylation of FLNA was demonstrated to be correlated with EMT. In turn, FLNA enhanced c-Met promoter activity by its interaction with smad2. Clinically, the expression of FLNA was significantly associated with c-Met protein levels in CRC tissues. These data established that FLNA could be a novel and reliable CRC marker and a potential therapeutic target against CRC.

Discovery and anticancer evaluation of a formononetin derivative against gastric cancer SGC7901 cells.

Background Gastric cancer (GC) is the second most common cause of cancer-related death worldwide. Novel anticancer drugs against gastric cancer are urgently needed. Methods Compound 10 was designed and synthesized via a molecular hybridization strategy based on the natural product formononetin. It was evaluated for their antiproliferative activity against three gastric cancer cell lines (SGC7901, MKN45 and MGC803). Results Derivative 10 displayed potently antiproliferative activity with an IC50 value of 1.07 µM against SGC7901 cells. Derivative 10 could inhibit the growth and migration against gastric cancer SGC7901 cells through the Wnt/ß-Catenin and AKT/mTOR pathways. From the in vivo expremints, it could effectively inhibited SGC7901 xenograft tumor growth in vivo without significant loss of the body weight. Conclusion Derivative 10 is an novel antitumor agent with potential for further clinical applications to treat gastric cancer. Graphical abstract.

Silencing TRIP13 inhibits cell growth and metastasis of hepatocellular carcinoma by activating of TGF-ß1/smad3.

BACKGROUND: TRIP13 is highly expressed in several cancers and is closely connected with cancer progression. However, its roles on the growth and metastasis of hepatocellular carcinoma (HCC), and the underlying mechanism are still unclear. METHODS: Combining bioinformatics with previous studies, the correlation between TRIP13 and HCC was predicted. TRIP13 expressions from 52 HCC patients and several cell lines were determined. The effects of silencing TRIP13 on cell viability, apoptosis, migration and invasion were respectively detected using CCK-8, flow cytometry and Transwell. qRT-PCR and western blot were performed to reveal associated mechanism. A HCC model was established in BALB/c-nu mice by transplanting HepG2 cells. TRIP13 protein expression and apoptosis in mice tissues were accordingly detected by Immunohistochemistry and TUNEL. RESULTS: High expression of TRIP13 in HCC affected the survival rate and it was enriched in RNA degradation and fatty acid metabolism according to bioinformatics and prediction from previous literature. Increased expression of TRIP13 in HCC patient tissues was associated with the progression of HCC. Silencing TRIP13 inhibited cell viability, migration and invasion, and induced cell apoptosis. TRIP13 knockdown also suppressed the formation of tumor in vivo. Meanwhile, silencing TRIP13 decreased the expressions of Ki67 and MMP-2 and increased the expressions of TIMP-2, active-caspase-3 and TGF-ß1/smad3 signaling- related genes. CONCLUSIONS: Silencing TRIP13 acts as a tumor suppresser of HCC to repress cell growth and metastasis in vitro and in vivo, and such a phenomenon possibly involved activation of TGF-ß1/smad3 signaling.

Evaluation of high-resolution esophageal manometry in patients with peroral endoscopic myotomy / 中国内镜杂志

Objective To observe the changes of esophageal pressure in patients with achalasia (AC) before and after peroral endoscopic myotomy (POEM), and to explore the value of high-resolution manometry (HRM) in evaluating the efficacy of POEM. Methods 38 cases were diagnosed as achalasia and treated with POEM from August 2015 to November 2016. Upper esophageal sphincter resting pressure (UESP), lower esophageal sphincter resting pressure (LESP), esophageal sphincter 4s integrated relaxation pressure (4sIRP) were detected by HRM before operation, at 1 week, 1 month after operation to evaluate the efficacy. Results A total of 38 patients with AC received POEM. At one week, one month after operation, the UESP were (45.34 ± 26.52) mmHg, (41.27 ± 20.09) mmHg, compared with that of before operation (49.58 ± 26.47) mmHg and the differences were not statistically significant. The differences in LESP, 4sIRP between before operation and at one week, one month after operation were statistically significant, P < 0.05. The differences in UESP, LESP and 4sIRP between 1 week and 1 month after operation were not statistically significant. Conclusion The pressure of lower esophageal sphincter was significantly reduced and the dysphagia was improved. HRM might play an important role in the assessment of AC received POEM.

Evaluation of high-resolution esophageal manometry in patients with peroral endoscopic myotomy / 中国内镜杂志

Objective To observe the changes of esophageal pressure in patients with achalasia (AC) before and after peroral endoscopic myotomy (POEM), and to explore the value of high-resolution manometry (HRM) in evaluating the efficacy of POEM. Methods 38 cases were diagnosed as achalasia and treated with POEM from August 2015 to November 2016. Upper esophageal sphincter resting pressure (UESP), lower esophageal sphincter resting pressure (LESP), esophageal sphincter 4s integrated relaxation pressure (4sIRP) were detected by HRM before operation, at 1 week, 1 month after operation to evaluate the efficacy. Results A total of 38 patients with AC received POEM. At one week, one month after operation, the UESP were (45.34 ± 26.52) mmHg, (41.27 ± 20.09) mmHg, compared with that of before operation (49.58 ± 26.47) mmHg and the differences were not statistically significant. The differences in LESP, 4sIRP between before operation and at one week, one month after operation were statistically significant, P < 0.05. The differences in UESP, LESP and 4sIRP between 1 week and 1 month after operation were not statistically significant. Conclusion The pressure of lower esophageal sphincter was significantly reduced and the dysphagia was improved. HRM might play an important role in the assessment of AC received POEM.