Calreticulin promotes migration and invasion of nasopharyngeal carcinoma cells by inducing cell EMT

AIM:To observe the expression of calreticulin (CRT) in nasopharyngeal carcinoma tissues, analyze the significance of clinical pathology and the influence on epithelial-mesencymal transition (EMT) of CNE2 cells. METHODS:The expression of calreticulin was detected by immunohistochemistry in 52 nasopharyngeal carcinoma and 57 nasopharyngeal benign tissues, and the significance of clinical pathology was evaluated. The calreticulin gene-specific small interfering RNA was constructed, and then was transfected into the NPC cell line CNE2 using the cationic liposome method. The effect of CRT on the morphological changes of the CNE2 cells was observed under light microscope. The effect of CRT on the cell migration and invasion abilities of the CNE2 cells was detected by Transwell migration and invasion assays. The expression of EMT-related proteins E-cadherin, vimentin, transforming growth factor (TGF)-β and matrix metalloproteinase (MMP)-9 in the CNE2 cells was determined by Western blot. RESULTS:The positive expression rate of CRT in the benign lesion tissues was 19.29% (11/57), which was significantly increased in the nasopharyngeal carcinoma tissues as 82.69% (43/52). The expression rate of CRT was positively correlated with the stage of nasopharyngeal carcinoma and lymph node metastasis (P<0.05). Knockdown of CRT expression made the CNE2 cells showing a spindle shape to a flat, cobblestone-like epithelial state change, arranged more compact, and the migration and invasion abilities were significantly decreased (P<0.05). Knockdown of CRT expression resulted in significant increase in the protein expression of E-cadhe-rin, and the decreases in the protein expression of vimentin, TGF-β and MMP-9 in the CNE2 cells (P<0.05). CONCLUSION:Calreticulin expression in nasopharyngeal carcinoma is significantly higher and positively correlated with nasopharyngeal carcinoma stage and lymph node metastasis. Calreticulin promotes cell migration and invasion of nasopharyngeal carcinoma CNE2 cells by inducing EMT.     

Effects of USP9X down-regulation on apoptosis and invasion ability of gastric carcinoma AGS cells

AIM: To investigate the effects of ubiquitin-specific peptidase 9, X-linked (USP9X) down-regulation on apoptosis and invasion ability in gastric carcinoma cells, and to explore its possible molecular mechanisms. METHODS: USP9X small interfering RNA (siRNA) and control siRNA were used to be transfected into gastric carcinoma AGS cells. The cells were divided into 3 groups, including untreated AGS group, control siRNA group and USP9X siRNA group. The expression of USP9X at mRNA and protein levels in the AGS cells with different treatments was determined by real-time PCR and Western blot. The cell viability was analyzed by CCK-8 assay. Flow cytometry and Boyden chamber were employed to examine the apoptosis and invasion ability of the AGS cells. RESULTS: USP9X siRNA significantly down-regulated the expression of USP9X at mRNA and protein levels in the AGS cells. Down-regulation of USP9X markedly induced apoptosis and reduced invasion ability of the gastric carcinoma AGS cells. Notably, down-regulation of USP9X significantly reduced the protein expression of Mcl-1 and MMP-2, but markedly increased the protein level of Bax. CONCLUSION: USP9X may be a key regulator for apoptosis and invasion in gastric carcinoma.     

Artesunate induces apoptosis of human hepatocellular carcinoma HepG2 cells by increasing generation of reactive oxygen species

AIM: To investigate the effect of reactive oxygen species (ROS) on the apoptosis of HepG2 cells induced by artesunate. METHODS: The effect of artesunate on the viability of HepG2 cells was measured by MTT assay. The morphological changes of the apoptotic cells were observed by the method of Hoechst 33258 fluorescence staining.The apoptosis of HepG2 cells was analyzed by flow cytometry. DCFH-DA was used to detect the changes of ROS generation during the process of apoptosis. The protein levels of Bax, Bcl-2, cleaved caspase-3 and cytochrome C (Cyt C) were determined by Western blot. HepG2 cells were pretreated with apocynin and then Western blot was used to detect the expression of p47^phox and p22^phox, and ROS changes were analyzed by flow cytometry. RESULTS: Compare with control group, the cell viability was obviously inhibited after treatment with artesunate for 24 h (P<0.05). The nuclei were densely stained, and the proportion of apoptotic cells was increased (P<0.05). ROS was increased significantly (P<0.05). The results of Western blot demonstrated that the expression level of Bax was increased, Bcl-2 was decreased, the ratio of Bax/Bcl-2 was increased, and the protein levels of cleaved caspase-3 and Cyt C were increased. Pretreatment with apocynin reduced the expression of p47^phox and p22^phox and the generation of ROS in the artesunate treatment group. CONCLUSION: Artesunate induces the apoptosis of HepG2 cells. The possible mechanism may be related to the increase in the generation of ROS.     

Progress on genomic aberrations in esophageal squamous-cell carcinoma

Esophageal squamous-cell carcinoma (ESCC) is one of the most common malignancies with poor prognosis in China. Since most clinical confirmation of the patients with ESCC is diagnosed at an advanced stage or with lymph node metastasis, the treatment effect was very poor. With the applications of high-throughput microarray and whole-genome sequencing or whole-exome sequencing, several novel cancer-related genes have been identified and revealed, and these genes may become new biomarkers or therapeutic targets. This review is to summarize the research progress in ESCC genome reported recently.     

Establishment of patient-derived esophageal squamous-cell carcinoma xenograft in mice and characteristics of signaling pathways related to proliferation in SCID mice

AIM: To establish and characterize the patient-derived esophageal squamous-cell carcinoma xenograft (PDECX) in mice. METHODS: The samples of human esophageal cancer were grafted into severe combined immunodeficient (SCID) mice. The xenografts were transferred to SCID mice when the first passage of xenografts grew up. The growth of tumors in the first, second and third passages was observed. HE staining was performed. The expression of CK5/6, p63 and p40 in the patient samples, and the first and third passages of the xenografts were detected by immunohistochemical analysis. The expression of mTOR, p-mTOR, p70S6K, p-p70S6K, Akt1, p-Akt (Ser473), Erk1/2 and p-Erk1/2 were determined by Western blot.RESULTS: The PDECX was successfully established. The positive expression of CK5/6, p63 and p40 in the xenografts was consistent with that in the patients' samples. The levels of phosphorylated and total proteins of proliferation-related signaling pathways were different in the xenografts from different patients.CONCLUSION: The PDECX model adequately reflects the tumal heterogeneity that is observed in the patients.     

Resection cystoplasty of a squamous cell carcinoma in a mare

A 22‐year‐old Arabian mare was examined for evaluation of haematuria of 2 months' duration. Complete blood cell count and chemistry revealed anaemia of chronic disease (i.e. normocytic, normochromic) and hypoproteinaemia. Cystoscopy revealed a haemorrhagic mass protruding into the lumen of the urinary bladder in the apical region. The mass was surgically removed by partial cystectomy performed through a caudal ventral midline laparotomy. Histological examination of the mass confirmed the diagnosis of squamous cell carcinoma. Tumours of the equine urinary bladder are rare, and when a partial cystectomy is indicated, a caudal ventral midline laparotomy may provide adequate surgical exposure even in adult horses.