Repression of circRNA_000684 inhibits malignant phenotypes of pancreatic ductal adenocarcinoma cells via miR-145-mediated KLF5.

BACKGROUND: Circular RNAs (circRNAs) are aberrantly expressed in pancreatic ductal adenocarcinoma (PDAC). In the current study, we investigated how circRNA_000684 affected the progression of PDAC, and how it regulated kruppel-like factor 5 (KLF5) and microRNA (miR)-145. METHODS: Differentially expressed circRNAs, miRs and genes related to PDAC as well as their targeting relationship were predicted using bioinformatics analyses. Binding relationships among circRNA_000684, miR-145 and KLF5 were verified using dual-luciferase reporter gene assay, RIP and RNA pull-down assay, respectively. The effects of circRNA_000684, miR-145, KLF5 on the malignant phenotypes of PDAC cells and human umbilical vein endothelial cell (HUVEC) angiogenesis were assessed using loss- and gain-of function experiments by CCK-8 assay, scratch test, Transwell and tube formation assays. RT-qPCR and Western blot analysis were used to determine MCM2, MMP2 and MMP9 and VEGFA expression. In addition, the roles of circRNA_000684, miR-145, and KLF5 in tumor growth were validated through in vivo experiments. RESULTS: Expression of CircRNA_000684 and KLF5 was upregulated, whereas miR-145 expression was downregulated in PDAC tissues and cells. CircRNA_000684 repression or miR-145 elevation inhibited the proliferation, invasion and migration of PDAC cells and HUVEC angiogenesis, as evidenced by lower levels of MCM2, MMP2 and MMP9 and VEGFA. CircRNA_000684 negatively regulated miR-145 expression, while miR-145 negatively regulated KLF5. In-vivo, circRNA_000684 elevation or miR-145 repression promoted tumor growth. CONCLUSION: Taken together, the present study provided evidence clarifying that circRNA_000684 could downregulate miR-145 expression and elevate KLF5 to promote the progression of PDAC.

Screening of characteristic genes in ulcerative colitis by integrating gene expression profiles.

BACKGROUND: This study aimed to screen the feature modules and characteristic genes related to ulcerative colitis (UC) and construct a support vector machine (SVM) classifier to distinguish UC patients. METHODS: Four datasets that contained UC and control samples were obtained from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) with consistency were screened via the MetaDE method. The weighted gene coexpression network (WGCNA) was used to distinguish significant modules based on the four datasets. The protein-protein interaction network was established based on intersection genes. Enrichment analysis of Gene Ontology (GO) biological processes (BPs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were established based on DAVID. An SVM combined with recursive feature elimination was also applied to construct a disease classifier for the disease diagnosis of UC patients. The efficacy of the SVM classifier was evaluated through receiver operating characteristic curves. RESULTS: Twelve highly preserved modules were obtained using the WGCNA, and 2009 DEGs with significant consistency were selected using the MetaDE method. Sixteen significantly related GO BPs and 12 KEGG pathways were obtained, such as cytokine-cytokine receptor interaction, cell adhesion molecules, and leukocyte transendothelial migration. Subsequently, 41 genes were used to construct an SVM classifier, such as CXCL1, CCR2, IL1B, and IL1A. The area under the curve (AUC) was 0.999 in the training dataset, whereas the AUC was 0.886, 0.790, and 0.819 in the validation set (GSE65114, GSE37283, and GSE36807, respectively). CONCLUSIONS: An SVM classifier based on feature genes might correctly identify healthy people or UC patients.

Circular RNA hsa_circ_0000673 promotes hepatocellular carcinoma malignance by decreasing miR-767-3p targeting SET.

The importance of circular RNAs (circRNAs) in human cancers has gradually been acknowledged. In hepatocellular carcinoma (HCC), several circRNAs have been reported to regulate tumor growth and metastasis. However, the role of hsa_circ_0000673 in HCC remains largely unknown. In this study, we found that hsa_circ_0000673 was significantly upregulated in HCC tissues compared to adjacent non-tumor tissues. Moreover, we found that hsa_circ_0000673 knockdown markedly inhibited the proliferation and invasion of HCC cells in vitro. Besides, hsa_circ_0000673 silence led to delayed tumor growth in vivo. In terms of mechanism, we showed that hsa_circ_0000673 directly associated with miR-767-3p in HCC cells. Via inhibiting miR-767-3p, hsa_circ_0000673 promoted HCC cell proliferation and invasion. Furthermore, we demonstrated that SET was a downstream effector of hsa_circ_0000673/miR-767-3p signaling. We showed that miR-767-3p could significantly promote SET expression by sponging miR-767-3p in HCC cells. Finally, rescue assays indicated that SET expression was essential for the effects of hsa_circ_0000673/miR-767-3p signaling on HCC cell proliferation and invasion. Taken together, our findings demonstrated that hsa_circ_0000673 promoted HCC malignant behaviors via regulating miR-767-3p/SET pathway.

Effect of sitagliptin, a DPP-4 inhibitor, against DENA-induced liver cancer in rats mediated via NF-κB activation and inflammatory cytokines.

The target of the current research was to investigate the anticancer activity of sitagliptin on diethylnitrosamine (DENA)-induced cancer in the liver. Wistar rats were treated with or without sitagliptin before DENA treatment. We detected liver weight, blood glucose, and histopathology of the liver. Serum biochemical markers like serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), serum alkaline phosphatase (SALP), gamma-glutamyl transpeptidase (GGTP), total bilirubin (TBR), total protein (TPR), and albumin (ALB) were also evaluated. In addition, lipid profile parameters comprising total cholesterol (TC), triglycerides, and high-density lipoprotein were also measured. Inflammatory mediators like interleukin-6 (IL-6), interleukin-1beta (IL-1ß), and tumor necrosis factor-alpha (TNF-α) were determined in liver homogenate. Furthermore, the activity of nuclear factor (NF-κB) was also measured. Our results showed that sitagliptin (10 and 20 mg/kg) in a dose-dependent manner expressively decreased the DENA-induced elevation of SGPT, SGOT, SALP, and GGTP. Whereas sitagliptin (10 and 20 mg/kg) in a dose-dependent mode reduced the level of TBR and increased the TPR and ALB as well as improved the liver histopathology alterations in DENA-exposed rats. Lipid profile was also restored by the sitagliptin (10 and 20 mg/kg) in a DENA-treated rats. The level of IL-1ß, IL-6, and TNF-α were suggestively suppressed. Moreover, pretreatment with sitagliptin (10 and 20 mg/kg) prevented the activation of NF-κB. In conclusion, sitagliptin (10 and 20 mg/kg) has a potential protective effect against DENA-induced liver cancer by inhibition of inflammation and NF-κB activation.

p38MAPK Signaling Enhances Glycolysis Through the Up-Regulation of the Glucose Transporter GLUT-4 in Gastric Cancer Cells.

BACKGROUND/AIMS: Previous studies have shown that p38MAPK is involved in gastric cancer, yet the underlying mechanism remains unclear. METHODS: q-PCR, Western blot and immunohistochemistry were used to explore the expression of PP2A and the phosphorylation of p38MAPK in gastric cancer tissues and normal gastric tissues. Activated p38MAPK in the gastric cancer cell line MKN45 using activator, then q-PCR, glucose uptake assay and colony formation assay were performed to determine whether p38MAPK promotes gastric cancer through the enhancement of glycolysis. After transfection of p38MAPK dominant negative mutation (p38DN) into MKN45 cells or MKN45 cells treated with an inhibitor of p38MAPK, Western blot was performed to detect the expression of GLUT-4. The knock down of MEF2α in MKN45 cells by siRNA was followed by Western blot and luciferase reporter assay to investigate the underlying mechanism of the role of p38MAPK in the promotion of gastric cancer. Finally, q-PCR, Western blot and immunohistochemistry were performed to examine GLUT-4 expression in gastric cancer tissues and normal gastric tissues. RESULTS: We found that p38MAPK activation significantly increases GLUT-4 expression and promotes glucose uptake and cell growth in gastric cancer cells. Inhibition of p38MAPK abrogates the up-regulation of GLUT-4. MEF2α knockdown abolishes p38MAPK-mediated GLUT-4 up-regulation. PP2A, an inhibitor of p38MAPK, is down-regulated in gastric cancer tissues, which might contribute to the activation of p38MAPK. CONCLUSIONS: Our data indicate that the abnormal activation of p38MAPK promotes glycolysis within gastric cancer cells through the upregulation of GLUT-4 in a MEF2a-dependent manner.

miR-133b acts as a tumor suppressor and negatively regulates FGFR1 in gastric cancer.

MicroRNAs (miRNAs) are a class of small noncoding RNAs that negatively regulate protein expression by binding protein-coding mRNAs and repressing translation. Accumulating evidence suggests that miRNAs are involved in cancer development and progression, acting as either tumor suppressors or oncogenes. Intriguingly, it has been shown that miR-133b was significantly downregulated in several types of cancers. However, its role and relevance in gastric cancer are still largely unknown. We showed that miR-133b was downregulated in human gastric cancer tissues and cell lines compared with nontumor counterparts by quantitative RT-PCR analysis. Overexpression of miR-133b could inhibit cell proliferation and colony formation of the gastric cancer cell lines MKN-45 and SGC-7901. Bioinformatics analysis indicated two putative miR-133b binding sites in the 3'-untranslated region of fibroblast growth factor receptor 1 (FGFR1) mRNA. In dual-luciferase reporter assay, miR-133b reduced the luciferase activity of Luc-FGFR1-wt, and mutation of miR-133b binding sites abolished the inhibitory effect of miR-133b. In this study, we found that miR-133b reduced the protein but not the mRNA levels of endogenous FGFR1. Furthermore, FGFR1 expression was upregulated in gastric cancer tissues and inversely correlated with miR-133b expression. Finally, knockdown of FGFR1 inhibited the growth of MKN-45 cells in a dose-dependent manner and overexpression of FGFR1 promoted the growth of GES-1 cells. These results indicate that miR-133b targets FGFR1 and inhibits gastric cancer cell growth, suggesting that it may serve as a tumor suppressive target in gastric cancer therapy.

A new lymph node ratio-based staging system for rectosigmoid cancer: a retrospective study with external validation.

BACKGROUND: This study evaluated the clinical value of a new American Joint Committee on Cancer (AJCC) tumor node metastasis (TNM) staging prediction model based on lymph node ratio (LNR) in rectosigmoid cancer (RSC). METHODS: The analysis included 1444 patients with nonmetastatic RSC diagnosed pathologically between 2010 and 2016 who were collected from the National Cancer Institute Surveillance, Epidemiology, and Results database. The AJCC N-stage was redefined according to the LNR cutoff point, and the ability of the new staging system to predict prognosis was compared with that of the AJCC TNM staging system. Data from 739 patients from our hospital were used for external validation. RESULTS: According to the number of examined lymph nodes and LNR, the N stage was divided into five groups (LNR0-5). The 5-year OS of patients divided according to the new T lymph node ratio M (TLNRM) staging into stage I (T1LNR1, T1LNR2), IIA (T1LNR3, T2LNR1, T2LNR2, T2LNR3, T1LNR4, T3LNR1), IIB (T2LNR4), IIC (T3LNR2, T4a LNR1, T1LNR5), IIIA (T3LNR3, T2LNR5, T4b LNR1, T4a LNR2, T3LNR4), IIIB (T3LNR5, T4a LNR3, T4a LNR4, T4b LNR2), and IIIC (T4b LNR3, T4a LNR5, T4b LNR4, T4b LNR5) was significantly different ( P <0.05). Decision curve analysis showed that the net income of the new TLNRM staging system for different decision thresholds was higher than the prediction line of the traditional eighth TNM staging system. The smaller Akaike information criterion and Bayesian information suggested that the new staging system had a higher sensitivity for predicting prognosis than the traditional staging system. TLNRM II and III patients benefited from adjuvant chemotherapy, while adjuvant chemotherapy did not improve the prognosis of TNM II patients. These findings were confirmed by the external validation data. CONCLUSION: The new TLNRM staging system was superior to the eighth edition AJCC staging system for staging and predicting the prognosis of patients with RSC and may become an effective tool in clinical practice.

The characteristics and medical applications of antler stem cells.

Antlers are the only fully regenerable mammalian appendages whose annual renewal is initiated by antler stem cells (ASCs), defined as a specialized type of mesenchymal stem cells (MSCs) with embryonic stem cell properties. ASCs possess the same biological features as MSCs, including the capacity for self-renewal and multidirectional differentiation, immunomodulatory functions, and the maintenance of stem cell characteristics after multiple passages. Several preclinical studies have shown that ASCs exhibit promising potential in wound healing, bone repair, osteoarthritis, anti-tissue fibrosis, anti-aging, and hair regeneration. Medical applications based on ASCs and ASC-derived molecules provide a new source of stem cells and therapeutic modalities for regenerative medicine. This review begins with a brief description of antler regeneration and the role of ASCs. Then, the properties and advantages of ASCs are described. Finally, medical research advances regarding ASCs are summarized, and the prospects and challenges of ASCs are highlighted.

Oncologic Nomogram for Stage I Rectal Cancer to Assist Patient Selection for Adjuvant (Chemo)Radiotherapy Following Local Excision.

Background: Because of the low rate of lymph node metastasis in stage I rectal cancer (RC), local resection (LR) can achieve high survival benefits and quality of life. However, the indications for postoperative adjuvant therapy (AT) remain controversial. Methods: A retrospective analysis was performed in 6,486 patients with RC (pT1/T2) using the Surveillance, Epidemiology, and End Results (SEER) database. Patients were initially diagnosed from 2004 to 2016; following LR, 967 received AT and 5,519 did not. Propensity score matching (PSM) was used to balance the confounding factors of the two groups; the Kaplan-Meier method and the log-rank test were used for survival analysis. Cox proportional hazards regression analysis was used to screen independent prognostic factors and build a nomogram on this basis. X-tile software was used to divide the patients into low-, moderate-, and high-risk groups based on the nomogram risk score. Results: Multivariate analysis found that age, sex, race, marital status, tumor size, T stage, and carcinoembryonic antigen (CEA) in the non-AT group were independent prognostic factors for stage I RC and were included in the nomogram prediction model. The C-index of the model was 0.726 (95% CI, 0.689-0.763). We divided the patients into three risk groups according to the nomogram prediction score and found that patients with low and moderate risks did not show an improved prognosis after AT. However, high-risk patients did benefit from AT. Conclusion: The nomogram of this study can effectively predict the prognosis of patients with stage I RC undergoing LR. Our results indicate that high-risk patients should receive AT after LR; AT is not recommended for low-risk patients.

CHSY1 is upregulated and acts as tumor promotor in gastric cancer through regulating cell proliferation, apoptosis, and migration.

Gastric cancer is one of the most frequently diagnosed malignant tumors, with rapid progression and poor prognosis. The role of chondroitin sulfate synthase 1 (CHSY1) in the development and progression of gastric cancer was explored and clarified in this study. The immunohistochemistry analysis of clinical tissue samples as well as data mining of public database showed that CHSY1 was significantly upregulated in gastric cancer and associated with more advanced tumor stage and poorer prognosis. In vitro loss-of-function experiments demonstrated the inhibited cell proliferation, colony formation, cell migration, as well as the promoted cell apoptosis by CHSY1 knockdown. Moreover, recovery of CHSY1 expression could attenuate the regulatory effects induced by CHSY1 knockdown. Correspondingly, gastric cancer cells with CHSY1 knockdown showed reduced tumorigenicity and slower tumor growth in vivo. In conclusion, this study identified CHSY1 as a tumor promotor in gastric cancer, which may be utilized as a novel indicator of patients' prognosis and therapeutic target for developing more effective drug for GC treatment.

Identification of an Immune Signature Predicting Prognosis Risk and Lymphocyte Infiltration in Colon Cancer.

Increasing studies have highlighted the effects of the tumor immune micro-environment (TIM) on colon cancer (CC) tumorigenesis, prognosis, and metastasis. However, there is no reliable molecular marker that can effectively estimate the immune infiltration and predict the CC relapse risk. Here, we leveraged the gene expression profile and clinical characteristics from 1430 samples, including four gene expression omnibus database (GEO) databases and the cancer genome atlas (TCGA) database, to construct an immune risk signature that could be used as a predictor of survival outcome and immune activity. A risk model consisting of 10 immune-related genes were screened out in the Lasso-Cox model and were then aggregated to generate the immune risk signature based on the regression coefficients. The signature demonstrated robust prognostic ability in discovery and validation datasets, and this association remained significant in the multivariate analysis after controlling for age, gender, clinical stage, or microsatellite instability status. Leukocyte subpopulation analysis indicated that the low-risk signature was enriched with cytotoxic cells (activated CD4/CD8+ T cell and NK cell) and depleted of myeloid-derived suppressor cells (MDSC) and regulatory T cells. Further analysis indicated patients with a low-risk signature harbored higher tumor mutation loads and lower mutational frequencies in significantly mutated genes of APC and FBXW7. Together, our constructed signature could predict prognosis and represent the TIM of CC, which promotes individualized treatment and provides a promising novel molecular marker for immunotherapy.

Multiple gastrointestinal metastases of squamous-cell lung cancer: A case report.

RATIONALE: Gastrointestinal multiple metastases of lung cancer are extremely rare. The majority of gastrointestinal metastasis cases are diagnosed at a late stage and the prognosis is extremely poor. This report describes the clinical characteristics and outcomes of a patient with gastrointestinal multiple metastases from squamous-cell lung cancer, with special emphasis on the diagnosis and treatment of metastatic lung cancer. PATIENT CONCERNS: A 61-year-old man who presented with progressive abdominal distention was admitted to our hospital. Radiological examinations showed changes of post-primary pulmonary tuberculosis and mechanical obstruction of the small bowl. Histopathological findings of gastroscopic examination and biopsy specimens showed a diagnosis of squamous-cell carcinoma in the body of the stomach. DIAGNOSES: Postoperative histopathology confirmed a gastrointestinal multiple squamous-cell carcinoma in stomach and small bowl. Finally, squamous-cell lung cancer was confirmed by lung biopsy. INTERVENTIONS: During his hospitalization urgent surgery was performed because of acute abdomen. The patient underwent a laparotomy with curative gastrectomy for gastric cancer and small bowel partial resection. The patient was recommended with combination chemotherapy of carboplatin and paclitaxel for 3 cycles. OUTCOMES: Six months later after operation, the patient succumbed to respiratory failure. LESSONS: We searched the related literature of gastrointestinal metastases from lung cancer and the clinical presentation, site of metastasis, diagnosis, treatment, and survival time in these cases were reviewed. The present study may increase the awareness of early diagnosis and appropriate treatment of metastatic lung cancer of gastrointestinal tract.

Eukaryotic translation initiation factor EIF3H potentiates gastric carcinoma cell proliferation.

Eukaryotic translation initiation factor 3 subunit H (EIF3H) is required for the progression of several types of cancer. However, little is known about the function of EIF3H in gastric carcinoma. To address this issue, in the present study, we investigated EIF3H genetic alterations in and expression of EIF3H in gastric cancer tissue samples using cBioPortal and Oncomine databases. Endogenous EIF3H expression was knocked down in MGC80-3 and AGS gastric cancer cell lines by lentivirus-mediated RNA interference. We confirmed the knockdown efficiency by quantitative real-time PCR and western blotting and evaluated the effects of EIF3H silencing on cell proliferation of gastric cancer with the cell viability and colony formation assays and by flow cytometry. The OncoPrint of EIF3H generated using cBioPortal indicated that EIF3H genetic alterations (mutation, deletion and amplification) were present in two gastric cancer sample sets. The Oncomine analysis revealed that EIF3H mRNA level was upregulated in gastric cancer tissues. EIF3H knockdown inhibited cell proliferation and colony formation in gastric cancer lines and led to cell cycle arrest at the G0/G1 phase, while inducing apoptosis via up- and downregulation of pro- and anti-apoptotic factors, respectively. These results indicate that EIF3H can serve as a novel therapeutic target for the clinical treatment of gastric cancer.

Knockdown of long noncoding RNA 00152 (LINC00152) inhibits human retinoblastoma progression.

BACKGROUND: A growing body of evidence supports the involvement of long noncoding RNA 00152 (LINC00152) in the progression and metastasis of multiple cancers. However, the exact roles of LINC00152 in the progression of human retinoblastoma (RB) remain unknown. We explored the expression and biological function of human RB. MATERIALS AND METHODS: The expression level of LINC00152 in RB tissues and cells was analyzed using quantitative real-time PCR. The function of LINC00152 was determined using a series of in vitro assays. In vivo, a nude mouse model was established to analyze the function of LINC00152. Gene and protein expressions were detected using quantitative real-time PCR and Western blot assays, respectively. RESULTS: The expression of LINC00152 mRNA was upregulated in RB tissues and cell lines. Knockdown of LINC00152 significantly inhibited cell proliferation, colony formation, migration, and invasion and promoted cell apoptosis and caspase-3 and caspase-8 activities in vitro, as well as suppressing tumorigenesis in vivo. We identified several genes related to proliferation, apoptosis, and invasion including Ki-67, Bcl-2, and MMP-9 that were transcriptionally inactivated by LINC00152. CONCLUSION: Taken together, these data implicate LINC00152 as a therapeutic target in RB.

miR-148b inhibits glycolysis in gastric cancer through targeting SLC2A1.

Although the molecular biology of GC has been well characterized, early diagnostic biomarkers and effective therapeutic options in gastric cancer are still under investigation. Here, we found that miR-148b expression decreased in human gastric cancer tissues compared with matched adjacent nontumor tissues by q-PCR analysis and in situ hybridization. Further investigation revealed that overexpression of miR-148b limited glycolysis including glucose consumption, lactate production in gastric cancer cell lines BGC-823 and MKN45. Bioinformatics prediction uncovered that a dedicated transporters solute carrier family 2 member 1 (SLC2A1), also called GLUT1, was the direct target of miR-148b. The target effects were further confirmed by luciferase assay and western blot analysis. Besides, a reverse correlation was observed between relative SLC2A1 and miR-148b expression in human GC tissues compared with matched adjacent nontumor tissues. Subsequently, SLC2A1 suppression by SLC2A1 siRNA or specific inhibitor restricted the reduced effects of glycolysis mediated by miR-148b while SLC2A1 overexpression abrogated the effect of miR-148b on glycolysis. Our findings provided new evidence of miR-148b in GC development through restraining glycolysis, highlighting the role of miR-148b as a new target for GC treatment.

miR-539 inhibits human colorectal cancer progression by targeting RUNX2.

Emerging evidence has shown that microRNAs (miRNAs) such as miR-539 play critical roles in carcinogenesis and progression in many types of cancer, including human colorectal cancer (CRC). However, the roles and underlying mechanism of miR-539 in CRC have not been well identified. The aims of this study were, therefore, to investigate the regulatory role and potential mechanism of miR-539 in human CRC. Here, we show that miR-539 expression is downregulated in CRC tissues and cell lines. The expression level of miR-539 is inversely associated with advanced clinical stage and lymph node metastasis. In vitro studies reveal that overexpression of miR-539 inhibits CRC cell proliferation and colony formation as well as migration and invasion; in vivo results demonstrate that overexpression of miR-539 dramatically reduces CRC xenograft tumor growth. Moreover, runt-related transcription factor 2 (RUNX2), a known oncogene, was identified as a target transcript of miR-539 in CRC by bioinformatic analysis, luciferase reporter assay, qPCR, and western blotting. RUNX2 expression levels were upregulated and inversely correlated with miR-539 expression in CRC tissues. Importantly, overexpression of RUNX2 without the 3'-untranslated region that is targeted by miR-539 partially reversed the inhibitory effect of miR-539 on CRC cell proliferation, migration, and invasion. Collectively, these findings demonstrate that miR-539 functions as a tumor suppressor in CRC, at least in part, by targeting RUNX2, supporting the targeting of the novel miR-539 as a potentially effective therapeutic approach for treatment of CRC.