2-Bromopalmitate inhibits malignant behaviors of HPSCC cells by hindering the membrane location of Ras protein.

Palmitoylation, which is mediated by protein acyltransferase (PAT) and performs important biological functions, is the only reversible lipid modification in organism. To study the effect of protein palmitoylation on hypopharyngeal squamous cell carcinoma (HPSCC), the expression levels of 23 PATs in tumor tissues of 8 HPSCC patients were determined, and high mRNA and protein levels of DHHC9 and DHHC15 were found. Subsequently, we investigated the effect of 2-bromopalmitate (2BP), a small-molecular inhibitor of protein palmitoylation, on the behavior of Fadu cells in vitro (50 µM) and in nude mouse xenograft models (50 µmol/kg), and found that 2BP suppressed the proliferation, invasion, and migration of Fadu cells without increasing cell apoptosis. Mechanistically, the effect of 2BP on the transduction of BMP, Wnt, Shh, and FGF signaling pathways was tested with qRT-PCR, and its drug target was explored with western blotting and acyl-biotinyl exchange assay. Our results showed that 2BP inhibited the transduction of the FGF/ERK signaling pathway. The palmitoylation level of Ras protein decreased after 2BP treatment, and its distribution in the cell membrane structure was reduced significantly. The findings of this work reveal that protein palmitoylation mediated by DHHC9 and DHHC15 may play important roles in the occurrence and development of HPSCC. 2BP is able to inhibit the malignant biological behaviors of HPSCC cells, possibly via hindering the palmitoylation and membrane location of Ras protein, which might, in turn, offer a low-toxicity anti-cancer drug for targeting the treatment of HPSCC.

Integrating US-guided FNAB, BRAFV600E mutation, and clinicopathologic characteristics to predict cervical central lymph-node metastasis in preoperative patients with cN0 papillary thyroid carcinoma.

BACKGROUND: The prevalence of cervical central lymph-node metastasis (CLNM) is high in patients with papillary thyroid carcinoma (PTC). There is considerable controversy surrounding the benefits of prophylactic central lymph-node dissection (pCLND) in patients with clinically negative central compartment lymph nodes (cN0). Therefore, it is crucial to accurately predict the likelihood of cervical CLNM before surgery to make informed surgical decisions. METHODS: Date from 214 PTC patients (cN0) who underwent partial or total thyroidectomy and pCLND at the Guizhou Provincial People's Hospital were collected and retrospectively analyzed. They were divided into two groups in accordance with cervical CLNM or not. Their information, including clinical characteristics, ultrasound (US) features, pathological results of fine-needle aspirations biopsy (FNAB), and other characteristics of the groups, was analyzed and compared using univariate and multivariate logistic regression analyses. RESULTS: A total of 214 patients were eligible in this study. Among them, 43.5% (93/214) of PTC patients had cervical CLNM, and 56.5% (121/214) did not. The two groups were compared using a univariate analyses, and there were no significant differences between the two groups in aspect ratio, boundary, morphology, component, and BRAFV600E (P > 0.05), and there were significant differences between gender, age, maximum tumor size, tumor location, capsule contact, microcalcifications, color Doppler flow imaging (CDFI), and Hashimoto's thyroiditis (HT) (P < 0.05). A multivariate logistic regression analysis was performed to further clarify the correlation of these indices. However, only age (OR = 2.455, P = 0.009), maximum tumor size (OR = 2.586, P = 0.010), capsule contact (OR = 3.208, P = 0.001), and CDFI (OR = 2.225, P = 0.022) were independent predictors of cervical CLNM. Combining these four factors, the area under the receiver-operating characteristic (ROC) curve for the joint diagnosis is 0.8160 (95% 0.7596-0.8725). Univariate analysis indicated that capsule contact (P = 0.001) was a possible predictive factor of BRAFV600E mutation. CONCLUSIONS: In conclusion, four independent predictors of cervical CLNM, including age < 45 years, tumor size > 1.0 cm, capsule contact, and rich blood flow, were screened out. Therefore, a comprehensive assessment of these risk factors should be conducted when designing individualized treatment regimens for PTC patients.

Effect of silencing colon cancer-associated transcript 2 on the proliferation, apoptosis and autophagy of gastric cancer BGC-823 cells.

The role of long non-coding RNAs (lncRNAs) in the carcinogenesis and progression of tumors has been receiving increasing attention. Colon cancer-associated transcript 2 (CCAT2), a type of oncogenic lncRNA, is regarded as a novel biomarker of poor prognosis and metastasis in various types of cancer. However, the molecular contributions of CCAT2 to gastric cancer (GC) progression remain largely unclear. The aim of the present study was to demonstrate the effect of silencing CCAT2 on the biological behavior of GC BGC-823 cells and illustrate the potential underlying molecular mechanisms. A short hairpin RNA interference plasmid pRNAT-U6.1-CCAT2 targeting CCAT2 was successfully constructed. At 48 h after transfection with the interference plasmid, the survival rate of BGC-823 cells was significantly decreased, as determined by the MTT assay. In addition, RT-qPCR results revealed that CCAT2 gene expression was effectively suppressed by the transfection, while POU domain class 5 transcription factor 1B (POU5F1B) gene expression was significantly decreased. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay further revealed that the apoptotic index was significantly higher in the interference group. Western blot analysis also demonstrated that the expression of beclin-1 protein was significantly increased, whereas the expression levels of phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) proteins were downregulated in the interference group. In conclusion, CCAT2 was able to positively regulate the expression of POU5F1B gene. Furthermore, silencing of CCAT2 gene inhibited the proliferation of BGC-823 cells, as well as induced apoptosis and autophagy in BGC-823 cells, by suppression of the PI3K/mTOR signaling pathways.

Right Internal Jugular Vein Cannulation: Carotid Artery-directed versus Sternocleidomastoid-directed Methods.

The aim of the present study was to explore a simple and safe method for central venous catheterization (CVC) from the right internal jugular vein (RIJV) by comparing carotid artery (CA) positioning with sternocleidomastoid (SCM) positioning. The medical records of patients who underwent CVC between January 2011 and January 2015 were retrospectively reviewed. Central venous catheters were inserted into the RIJV either above the level of the cricoid cartilage using the CA-directed method (419 patients, Group 1) or below the level of the cricoid cartilage using the SCM-directed method (436 patients, Group 2). Success rate and related complications of catheterization were evaluated in the two groups. The total success rate of RIJV cannulation in Group 1 (97.2%) was higher than that in Group 2 (94.5%). Moreover, the success rate at first attempt was significantly higher in Group 1 than in Group 2 (92.4% vs 86.9%). The incidence of hematoma was 1.6 per cent in Group 1 and 3.8 per cent in Group 2. The rate of other complications such as pneumothorax, catheter-related infections, and catheter occlusion did not significantly differ between the groups. In conclusions, CA-directed RIJV cannulation is more effective and simple to perform than the SCM-directed method, and should become the preferred CVC technique in the absence of ultrasound guidance.

Laparoscopic hepatectomy for liver metastases from colorectal cancer: a meta-analysis.

BACKGROUND: Liver resection can improve long-term survival for liver metastases from colorectal cancer. Laparoscopic hepatectomy is gaining increasing applications in colorectal liver metastases. We conducted a meta-analysis to investigate the safety, feasibility, and efficacy of laparoscopic liver resection compared with open hepatectomy for patients with colorectal liver metastases. MATERIALS AND METHODS: We performed both database and manual searching for comparative studies published before June 2013 without language or region restriction. Outcomes of interest consisted of perioperative outcomes and oncologic outcomes. RESULTS: Seven observational studies including 624 patients (241 in the laparoscopic group, 383 in the open group) were included. No randomized controlled trials were available. Pooled long-term oncologic outcomes of overall survival (hazard ratio=0.844; 95% confidence interval [CI] 0.412, 1.730; P=.644; I(2)=80.6%) and disease-free survival (hazard ratio=1.234; 95% CI 0.652, 2.333; P=.518; I(2)=79.6%) were similar in both groups. Subgroup analyses of studies with high quality and homogeneity confirmed the above outcomes. However, a lower incidence of R1 resection was observed in the laparoscopic group (relative risk [RR]=0.357; 95% CI 0.180, 0.708; P=.003; I(2)=0.0%) than in the open group. As for perioperative outcomes, laparoscopic hepatectomy presented a lower occurrence of postoperative complications (RR=0.647; 95% CI 0.477, 0.877; P=.005; I(2)=0.0%) and similar mortality (RR=0.625; 95% CI 0.12, 3.25; P=.576; I(2)=0.0%); less blood loss and less need for transfusion were also found in laparoscopic patients, whereas comparable operative time and length of hospital stay were required in the two groups. CONCLUSIONS: Laparoscopic hepatectomy is a safe procedure for colorectal liver metastases with long-term survival comparable to that of open hepatectomy. More prospective studies with adequate subgroup analyses are awaited to construct defined criteria for patient selection. Future randomized controlled trials are needed to eliminate potential selection bias and to confirm this conclusion.

Expression of microRNA-150 targeting vascular endothelial growth factor-A is downregulated under hypoxia during liver regeneration.

Vascular endothelial growth factor (VEGF) is a factor that stimulates the proliferation of sinusoidal endothelial cells and hepatocytes during liver regeneration (LR). The present study aimed to screen and validate a microRNA (miRNA) that targets VEGF-A with relative specificity and to elucidate the potential association between hypoxia-inducible factor-1α (HIF­1α) and miRNA expression in the early phase of LR. Changes in the expression of miRNAs, which were predicted to target VEGF-A using online databases, were detected at 12, 24 and 48 h following a 70% partial hepatectomy (PHx) using quantitative PCR (qPCR). An inhibitor of the most downregulated miRNA was transfected into the primary hepatocytes in order to observe changes in the expression of the VEGF-A gene. The expression of HIF-1α protein in the regenerating liver was investigated using western blot analysis. The expression levels of HIF-1α mRNA (messenger RNA), the selected miRNA and VEGF-A mRNA in an anoxic model of hepatocytes was examined with qPCR. Of seven putative miRNAs, the expression of miR-150 exhibited the sharpest downregulation from 12-48 h. The micrOFF™ miR-150 inhibitor significantly elevated the expression levels of VEGF-A mRNA and protein 48 h after transfection. Thus, VEGF-A may be a downstream target of miR-150 during LR. Furthermore, HIF-1α protein expression increased to its highest level 24 h following PHx. miR-150 expression was inhibited and the expression of VEGF-A mRNA increased accordingly in the hypoxia-induced hepatocytes. Our results suggest that miR-150 expression is subject to negative regulation by HIF-1α.

Co-inhibition of HSP70/HSP90 synergistically sensitizes nasopharyngeal carcinoma cells to thermotherapy.

The upregulation of both HSP70 and HSP90 frequently compromises the effects of thermotherapy. The co-inhibition of HSP70/HSP90 may be preferable to enhance the effects of thermotherapy on nasopharyngeal carcinoma cells. The changes of HSP70 and HSP90 were detected after thermotherapy in human nasopharyngeal cancer cell HNE1. 17-Dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG) and quercetin were used to inhibit the activity of HSP90 and HSP70. The enhanced effects were evaluated in vitro and in vivo. Both HSP70 and HSP90 were upregulated promptly in HNE1 after thermotherapy. Single inhibition of HSP70 resulted in overexpression and delayed descent of HSP90. The co-inhibition of HSP70/HSP90 with quercetin plus 17-DMAG significantly increased apoptosis in hyperthermia-treated HNE1 cells both in vitro and in vivo. The co-inhibition of HSP70/HSP90 synergistically sensitizes nasopharyngeal carcinoma cells to hyperthermia.