Downregulation of Roundabout guidance receptor 2 suppresses hepatocellular carcinoma progression by interacting with Y-box binding protein 1.

Roundabout guidance receptor 2 (Robo2) is closely related to malignant tumors such as pancreatic cancer and liver fibrosis, but there is no relevant research on the role of Robo2 in HCC. The study will further explore the function and mechanism of Robo2 and its downstream target genes in HCC. Firstly, Robo2 protein levels in human HCC tissues and paired adjacent normal liver tissues were detected. Then we established HepG2 and Huh7 hepatoma cell lines with knock-down Robo2 by transfection with lentiviral vectors, and examined the occurrence of EMT, proliferation and apoptosis abilities in HCC cells by western blot, flow cytometry, wound healing assay and TUNEL staining. Then we verified the interaction between Robo2 and its target gene by Co-IP and immunofluorescence co-staining, and further explored the mechanism of Robo2 and YB-1 by rescue study. The protein expression level of Robo2 in HCC was considerably higher than that in the normal liver tissues. After successfully constructing hepatoma cells with knock-down Robo2, it was confirmed that down-regulated Robo2 suppressed EMT and proliferation of hepatoma cells, and accelerated the cell apoptosis. High-throughput sequencing and validation experiments verified that YB-1 was the downstream target gene of Robo2, and over-expression of YB-1 could reverse the apoptosis induced by Robo2 down-regulation and its inhibitory effect on EMT and proliferation. Robo2 deficiency inhibits EMT and proliferation of hepatoma cells and augments the cell apoptosis by regulating YB-1, thus inhibits the occurrence of HCC and provides a new strategy for the treatment of HCC.

miR-17-5p promotes the invasion and migration of colorectal cancer by regulating HSPB2.

MicroRNA (miRNA) can affect tumor progression by regulating cell proliferation, apoptosis and metastasis. A significant upregulation of miR-17-5p expression was found in colorectal cancer (CRC) tissues by miRNA microarray chip analysis. However, the underlying mechanism of miR-17-5p in CRC is still unclear. The mRNA expression of miR-17-5p was significantly higher in CRC tissues than in adjacent normal tissues. In CRC group, the expression of miR-17-5p in cancer tissues with lymph node metastasis was higher compared with those without lymph node metastasis. The biological function of miR-17-5p was demonstrated through CCK-8, colony formation, flow cytometry and transwell assays. Overexpression of miR-17-5p inhibited CRC cell apoptosis, as well as promoting proliferation, migration and invasion. Transcriptome sequencing and miRNA target prediction software suggested that HSPB2 might be a target gene of miR-17-5p and luciferase reporter detection validated for the first time that miR-17-5p binds directly to the 3'-UTR of HSPB2. In the rescue experiment, the tumor suppressive effect of HSPB2 was detected and miR-17-5p could promote cell proliferation, migration and invasion by targeting HSPB2. Taken together, miR-17-5p promotes invasion and migration by inhibiting HSPB2 in CRC, thereby implicating its potential as a novel diagnostic biomarker and therapeutic target for CRC.

ITGB4 as a novel serum diagnosis biomarker and potential therapeutic target for colorectal cancer.

PURPOSE: To develop new and effective biomarkers for the diagnosis of colorectal cancer (CRC). EXPERIMENTAL DESIGN: The serum expression of ITGB4 (49 CRC and 367 HC) was detected by enzyme-linked immunosorbent assay (ELISA), and its diagnostic value was analyzed using the receiver operating characteristic (ROC) curve. The sensitivity and specificity of ITGB4 in CRC diagnosis were calculated through statistical analysis. The optimal clinical cutoff value was calculated using the Youden index, and diagnostic efficacy was analyzed in a larger serum sample (98 CRC and 1631 non-CRC). The expression of ITGB4 was measured by CyTOF (cell experimental technology) at the single-cell level, and characteristics were analyzed using viSNE and SPADE TREE. RESULTS: Serum ITGB4 and CEA levels were significantly higher in CRC patients than in HC and non-CRC patients. The use of serum ITGB4 levels for the diagnosis of CRC has a high sensitivity (79%) but not high specificity when the clinical cutoff value was 0.70 ng/mL. However, the optimal cutoff value was 1.6 ng/mL with 86.2% specificity and 52.0% sensitivity, and the diagnostic efficacy was greatly improved with high specificity (82.0%) and sensitivity (71.4%) when combined with CEA. ITGB4 expression characteristics were measured and related to the expression of EpCAM, Ck8/18, and perforin at the single-cell level. Single-cell analysis showed that cell clusters with low expression of CK8/18 and ITGB4 were more sensitive to 5FU and radiotherapy (RT). CONCLUSIONS: ITGB4 is an effective diagnostic serum biomarker and a potential therapeutic target for CRC.

Reduced Kiss­1 expression is associated with clinical aggressive feature of gastric cancer patients and promotes migration and invasion in gastric cancer cells.

Gastric cancer (GC) causes high morbidity and mortality in patients largely due to its invasion and metastasis. Kiss­1 has been shown to be a metastasis suppressor in various malignancies. However, its clinical significance and biological functions in GC have not been thoroughly investigated. The present study investigated the association between Kiss­1 expression and its methylation status and clinicopathological features in GC. Kiss­1 expression was reduced in GC and its low expression was associated with poor histological grade, lymph node metastasis and TNM III+IV stage. Kiss­1 overexpression in AGS GC cells significantly inhibited cell proliferation, migration and invasion in vitro. Kiss­1 knockdown promoted the proliferation, migration and invasion of HGC­27 cells. In summary, the data demonstrated that a low expression of Kiss­1 played a suppressive role for the proliferation, migration and invasion of GC cells. Its expression and methylation levels were associated with the clinical progression of GC. Thus, Kiss­1 is a potential diagnostic and prognostic marker as well as a new target for the treatment of GC.