Ya-Nan Yu

Knockdown of ZFX inhibits gastric cancer cell growth in vitro and in vivo via downregulating the ERK-MAPK pathway.

Zinc finger protein X-linked (ZFX) is a zinc finger transcription factor encoded on the X chromosome. Here, we found that ZFX expression was significantly upregulated in gastric cancer (GC) cell lines and tissues. Knockdown of ZFX induced significant apoptosis and cell cycle arrest in SGC7901 and MGC803 cells. Moreover, we demonstrated for the first time that knockdown of ZFX inhibited gastric cancer cell growth in vitro and in vivo via downregulating the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK-MAPK) pathway. Therefore, ZFX play a prominent role in GC tumorigenicity and may have potential applications in the diagnosis or treatment of GC.

Berberine may rescue Fusobacterium nucleatum -induced colorectal tumorigenesis by modulating the tumor microenvironment

Background Accumulating evidence links colorectal cancer (CRC) with the intestinal microbiota. However, the disturbance of intestinal microbiota and the role of Fusobacterium nucleatum during the colorectal adenoma-carcinoma sequence have not yet been evaluated. Methods 454 FLX pyrosequencing was used to evaluate the disturbance of intestinal microbiota during the adenoma-carcinoma sequence pathway of CRC. Intestinal microbiota and mucosa tumor-immune cytokines were detected in mice after introducing 1,2-dimethylhydrazine (DMH), F. nucleatum or Berberine (BBR), using pyrosequencing and Bio-Plex Pro™ cytokine assays, respectively. Protein expressions were detected by western blotting. Results The levels of opportunistic pathogens, such as Fusobacterium, Streptococcus and Enterococcus spp. gradually increased during the colorectal adenoma-carcinoma sequence in human fecal and mucosal samples. F. nucleatum treatment significantly altered lumen microbial structures, with increased Tenericutes and Verrucomicrobia (opportunistic pathogens) (P < 0.05 = in wild-type C57BL/6 and mice with DMH treatment). BBR intervention reversed the F. nucleatum-mediated increase in opportunistic pathogens, and the secretion of IL-21/22/31, CD40L and the expression of p-STAT3, p-STAT5 and p-ERK1/2 in mice, compared with mice fed with F. nucleatum alone. Conclusions F. nucleatum colonization in the intestine may prompt colorectal tumorigenesis. BBR could rescue F. nucleatum-induced colorectal tumorigenesis by modulating the tumor microenvironment and blocking the activation of tumorigenesis-related pathways.

Probiotics Clostridium butyricum and Bacillus subtilis ameliorate intestinal tumorigenesis

AIMS To investigate the antitumor effects of probiotics Clostridium butyricum and Bacillus subtilis on colorectal cancer (CRC) progression. MATERIALS & METHODS The effects of C. butyricum and B. subtilis on CRC cells were studied. Male C57BL/6 mice with 1,2-dimethylhydrazine dihydrochloride (DMH)-induced CRC were intervened by these two probiotics and the antitumor effects were examined by comparing the tumor incidence and detecting the inflammatory and immune-related markers. RESULTS & CONCLUSIONS C. butyricum and B. subtilis inhibited the proliferation of CRC cells, caused cell cycle arrest and promoted apoptosis. In vivo, these two probiotics inhibited the development of DMH-induced CRC. The molecular mechanism involved reduced inflammation and improved immune homeostasis. This work establishes a basis for the protective role of probiotics B. subtilis and C. butyricum in intestinal tumorigenesis.

TMEFF2 Deregulation Contributes to Gastric Carcinogenesis and Indicates Poor Survival Outcome

Purpose: The role and clinical implication of the transmembrane protein with EGF and two follistatin motifs 2 (TMEFF2) in gastric cancer is poorly understood. Experimental Design: Gene expression profile analyses were performed and Gene Set Enrichment Analysis (GSEA) was used to explore its gene signatures. AGS and MKN45 cells were transfected with TMEFF2 or control plasmids and analyzed for gene expression patterns, proliferation, and apoptosis. TMEFF2 expression was knocked down with shRNAs, and the effects on genome stability were assessed. Interactions between TMEFF2 and SHP-1 were determined by mass spectrometry and immunoprecipitation assays. Results: Integrated analysis revealed that TMEFF2 expression was significantly decreased in gastric cancer cases and its expression was negatively correlated with the poor pathologic stage, large tumor size, and poor prognosis. GSEA in The Cancer Genome Atlas (TCGA) and Jilin datasets revealed that cell proliferation, apoptosis, and DNA damage–related genes were enriched in TMEFF2 lower expression patients. Gain of TMEFF2 function decreased cell proliferation by increasing of apoptosis and blocking of cell cycle in gastric cancer cells. The protein tyrosine phosphatase SHP-1 was identified as a binding partner of TMEEF2 and mediator of TMEFF2 function. TMEFF2 expression positively correlated with SHP-1, and a favorable prognosis was more likely in patients with gastric cancer with higher levels of both TMEFF2 and SHP-1. Conclusion: TMEFF2 acts as a tumor suppressor in gastric cancer through direct interaction with SHP-1 and can be a potential biomarker of carcinogenesis. Clin Cancer Res; 20(17); 4689–704. ©2014 AACR.

miR-194 as a Predictor for Adenoma Recurrence in Patients with Advanced Colorectal Adenoma after Polypectomy

microRNAs (miRNA) are promising predictors in colorectal cancer (CRC). We investigated whether miRNAs could predict adenoma recurrence in patients with advanced colorectal adenoma (ACRA) after polypectomy. miRNA expression profiling was performed by miRNA microarray to identify recurrence-related miRNAs. Candidate miRNAs extracted from formalin-fixed paraffin-embedded blocks of patients with ACRA were measured using real-time PCR. Logistic regression analysis was conducted to investigate whether validated miRNA expression profiles were independent from other known adenoma recurrence risk factors. The prognostic values of six miRNAs and three independent risk factors were assessed by the area under the receiver operating characteristic (ROC) curve analysis. The expressions of six candidate miRNAs were significantly decreased from levels in normal colorectal tissue compared with ARCA with adenoma recurrence (RACRA) in this retrospective cohort. However, only miRNA (miR)-194 emerged as a practical predictor. The sensitivity and specificity of miR-194 as a predictor were 71.0% and 78.0%, respectively, at a cutoff value of 0.1311 in the retrospective cohort. Sensitivity and specificity were 76.1% and 77.2%, respectively, in the prospective cohort using the same cutoff value. Low expression levels of miR-194, adenoma size ≥2 cm, and ≥3 adenomas were independent risk factors for adenoma recurrence. Moreover, low expression of miR-194 was a better predictor of adenoma recurrence than the adenoma size and numbers according to ROC curve analysis. miR-194 may be an independent predictor for adenoma recurrence in patients with ACRA after polypectomy. Cancer Prev Res; 7(6); 607–16. ©2014 AACR.

The role of ERK2 in colorectal carcinogenesis is partly regulated by TRAPPC4

The extracellular signal‐regulated kinase (ERK), mitogen‐activated protein kinase (MAPK) pathway is an important cell proliferation pathway. We previously reported that the transport protein particle complex 4 (TRAPPC4), ERK2 interaction may activate ERK1/2, modulate pERK2 nuclear localization and regulate proliferation and apoptosis in colorectal cancer (CRC) cells. The present study further investigated the function of the TRAPPC4–ERK2 interaction in CRC in vitro and in vivo. Silencing of TRAPPC4 induced G0/G1 phase cell cycle arrest, upregulated p21 and downregulated cyclin B1 in CRC cells. Overexpression of TRAPPC4 after ERK2 silencing decreased the percentage of G0/G1 phase cells, increased the percentage of G2/M and S phase cells, downregulated p21, upregulated cyclin B1, and enhanced CRC cell viability. Immunohistochemical staining revealed that knockdown of TRAPPC4 downregulated pERK2, whereas overexpression of TRAPPC4 upregulated pERK2. Epidermal growth factor (EGF) stimulated upregulation of TRAPPC4 and pERK2 in SW1116 cells; EGF stimulation or overexpression of TRAPPC4 induced pERK2 nuclear translocation. Silencing of TRAPPC4 reduced SW1116 xenograft tumor growth in vivo, whereas overexpression of TRAPPC4 increased tumor growth, compared to control tumors. Moreover, modulation of TRAPPC4 expression in vivo affected the levels of pERK2 in the cytoplasm and nucleus and expression of p21. These results conclusively demonstrate that TRAPPC4 regulates ERK2 activation and also affects the distribution of activated pERK2 in CRC cells. The ability of ERK2 to play a role in colorectal carcinogenesis depends, at least in part, on TRAPPC4.

Role of C9orf140 in the promotion of colorectal cancer progression and mechanisms of its upregulation via activation of STAT5, β-catenin and EZH2

C9orf140 is a newly identified and characterized gene which is associated with cell proliferation and tumorigenicity. Expression of C9orf140 is upregulated in human gastric cancer and colorectal cancer (CRC); however, little is known about its role in CRC progression. We have investigated the clinical significance, biological effects and mechanisms of C9orf140 signaling. We found that the expression of C9orf140 is dramatically increased in a subset of CRC and correlates significantly with vascular invasion and lymph node metastasis. Our finding showed that knockdown of C9orf140 significantly reduced cell proliferation and invasion in vitro and dramatically increased overall survival and decreased lung metastasis in vivo. Conversely, overexpression of C9orf140 significantly increased lung metastasis and shortened overall survival when compared with control tumors. C9orf140-induced CRC cell invasion may depend on promoting the epithelial-mesenchymal transition progression. STAT5 may directly interact with the enhancer of zeste homolog 2 (EZH2) and β-catenin to enhance C9orf140 gene transactivation. Furthermore, C9orf140 may participate in cell invasion which is induced by STAT5, EZH2 or β-catenin activation. We describe the role of C9orf140 in CRC progression and find that C9orf140 overexpression may be regulated by STAT5, EZH2 and β-catenin interaction.

MicroRNA-508 defines the stem-like/mesenchymal subtype in colorectal cancer

Colorectal cancer includes an invasive stem-like/mesenchymal subtype, but its genetic drivers, functional, and clinical relevance are uncharacterized. Here we report the definition of an altered miRNA signature defining this subtype that includes a major genomic loss of miR-508. Mechanistic investigations showed that this miRNA affected the expression of cadherin CDH1 and the transcription factors ZEB1, SALL4, and BMI1. Loss of miR-508 in colorectal cancer was associated with upregulation of the novel hypoxia-induced long noncoding RNA AK000053. Ectopic expression of miR-508 in colorectal cancer cells blunted epithelial-to-mesenchymal transition (EMT), stemness, migration, and invasive capacity in vitro and in vivo In clinical colorectal cancer specimens, expression of miR-508 negatively correlated with stemness and EMT-associated gene expression and positively correlated with patient survival. Overall, our results showed that miR-508 is a key functional determinant of the stem-like/mesenchymal colorectal cancer subtype and a candidate therapeutic target for its treatment.Significance: These results define a key functional determinant of a stem-like/mesenchymal subtype of colorectal cancers and a candidate therapeutic target for its treatment. Cancer Res; 78(7); 1751-65. ©2018 AACR.

Retracted: Role of STAT3 and vitamin D receptor in EZH2-mediated invasion of human colorectal cancer

The above article from The Journal of Pathology, published online on 7 June 2013 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal Editor‐in‐Chief, Prof. C. Simon Herrington, and John Wiley & Sons Limited. Some sequences in Figure 6C were mistakenly identified, with consequent errors in the description of this figure and in the Materials and Methods section. Additionally, in Figures 5C, 5F and 7 some images were duplicated and erroneously presented as unique. The authors apologise to readers of the journal.

Retracted : Role of STAT3 and vitamin D receptor in EZH2 -mediated invasion of human colorectal cancer : STAT3 up-regulates EZH2 which may deregulate VDR

The above article from The Journal of Pathology, published online on 7 June 2013 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal Editor‐in‐Chief, Prof. C. Simon Herrington, and John Wiley & Sons Limited. Some sequences in Figure 6C were mistakenly identified, with consequent errors in the description of this figure and in the Materials and Methods section. Additionally, in Figures 5C, 5F and 7 some images were duplicated and erroneously presented as unique. The authors apologise to readers of the journal.