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.

Application value of CyTOF 2 mass cytometer technology at single-cell level in human gastric cancer cells.

Chemotherapy and radiotherapy are main adjuvant therapies for the treatment of gastric cancer, the treatment effects are individual difference, but the specific mechanism is unknown. CyTOF 2 mass cytometer (CyTOF) enables the detecting up to 135 parameters on single cell, the emergence of which is an opportunity for proteomics research. We first tried to apply CyTOF technique to gastric cancer cells. We verified applicability of CyTOF in gastric cancer cells, and analyzed the responses of seventeen proteins to chemoradiotherapy in human gastric cancer AGS cells. To analyze the high dimensional CyTOF data, we used two statistical and visualization tools including viSNE and Citrus. Two specific clusters were found which had differences in protein expression profiles. CyTOF technology is proved feasibility and value at single cell level of gastric cancer.

Modified Exosomes Reduce Apoptosis and Ameliorate Neural Deficits Induced by Traumatic Brain Injury.

Apoptosis contributes to the pathogenesis of traumatic brain injury (TBI). Engineered exosomes incorporated with therapeutic nuclear acids have been explored for gene therapy for human diseases. The current study sought to investigate the effect of modified exosome-containing plasmids expressing B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X-protein (Bax) short hairpin RNA (shRNA) on apoptosis and neural functions after TBI. C57BL/6J mice were subjected to controlled cortical impact injury and were treated with the modified exosomes. The results showed that modified exosomes attenuated the decrease of myeloid cell leukemia-1 (Mcl-1), X-linked inhibitor of apoptosis protein (XIAP), and Survivin protein levels in the brain and reduced Cytochrome c release from mitochondria to cytosol after TBI. They also attenuated the impairments of miniature excitatory postsynaptic current (mEPSC) and long-term potentiation (LTP) in the hippocampus of TBI mice and improved the motor and cognitive behaviors after TBI. These results suggested that the modified exosomes might reduce apoptosis and ameliorate neural and functional deficits in mouse models of TBI.

Mitochondrial dysfunction and inhibition of myoblast differentiation in mice with high-fat-diet-induced pre-diabetes.

Pre-diabetes is characterized by impaired glucose tolerance (IGT) and/or impaired fasting glucose. Impairment of skeletal muscle function is closely associated with the progression of diabetes. However, the entire pathological characteristics and mechanisms of pre-diabetes in skeletal muscle remain fully unknown. Here, we established a mouse model of pre-diabetes, in which 6-week-old male C57BL6/J mice were fed either normal diet or high-fat diet (HFD) for 8 or 16 weeks. Both non-fasting and fasting glucose levels and the results of glucose and insulin tolerance tests showed that mice fed an 8-week HFD developed pre-diabetes with IGT; whereas mice fed a 16-week HFD presented with impaired fasting glucose and impaired glucose tolerance (IFG-IGT). Mice at both stages of pre-diabetes displayed decreased numbers of mitochondria in skeletal muscle. Moreover, IFG-IGT mice exhibited decreased mitochondrial membrane potential and ATP production in skeletal muscle and muscle degeneration characterized by a shift in muscle fibers from predominantly oxidative type I to glycolytic type II. Western blotting and histological analysis confirmed that myoblast differentiation was only inhibited in IFG-IGT mice. For primary skeletal muscle satellite cells, inhibition of differentiation was observed in palmitic acid-induced insulin resistance model. Moreover, enhanced myoblast differentiation increased glucose uptake and insulin sensitivity. These findings indicate that pre-diabetes result in mitochondrial dysfunction and inhibition of myoblast differentiation in skeletal muscle. Therefore, interventions that enhance myoblast differentiation may improve insulin resistance of diabetes at the earlier stage.

Transferrin-Modified Nanoparticles for Photodynamic Therapy Enhance the Antitumor Efficacy of Hypocrellin A.

Photodynamic therapy (PDT) has emerged as a potent novel therapeutic modality that induces cell death through light-induced activation of photosensitizer. But some photosensitizers have characteristics of poor water-solubility and non-specific tissue distribution. These characteristics become main obstacles of PDT. In this paper, we synthesized a targeting drug delivery system (TDDS) to improve the water-solubility of photosensitizer and enhance the ability of targeted TFR positive tumor cells. TDDS is a transferrin-modified Poly(D,L-Lactide-co-glycolide (PLGA) and carboxymethyl chitosan (CMC) nanoparticle loaded with a photosensitizer hypocrellin A (HA), named TF-HA-CMC-PLGA NPs. Morphology, size distribution, Fourier transform infrared (FT-IR) spectra, encapsulation efficiency, and loading capacity of TF-HA-CMC-PLGA NPs were characterized. In vitro TF-HA-CMC-PLGA NPs presented weak dark cytotoxicity and significant photo-cytotoxicity with strong reactive oxygen species (ROS) generation and apoptotic cancer cell death. In vivo photodynamic antitumor efficacy of TF-HA-CMC-PLGA NPs was investigated with an A549 (TFR positive) tumor-bearing model in male athymic nude mice. TF-HA-CMC-PLGA NPs caused tumor delay with a remarkable tumor inhibition rate of 63% for 15 days. Extensive cell apoptosis in tumor tissue and slight side effects in normal organs were observed. The results indicated that TDDS has great potential to enhance PDT therapeutic efficacy.