Downregulation of PDGF-D Inhibits Proliferation and Invasion in Breast Cancer MDA-MB-231 Cells.

BACKGROUND: The platelet derived growth factor-D (PDGF-D) plays an important role in breast tumor aggressiveness. However, limited study has investigated the effect of silencing PDGF-D on the biological function of breast cancer. The purpose of this study is to clarify the potential value of PDGF-D as a target for breast cancer treatment. METHODS: Reverse transcription-polymerase chain reaction and western blot were used to detect PDGF-D expression in 5 different breast cancer cells. The lentiviral vector was usd to silence PDGF-D in MDA-MB-231 cells. Then, Methyl Thiazolyl Tetrazolium was used to detect cell viability, 5-Ethynyl-2'- deoxyuridine and a soft agar assay were used to detect cell proliferation and clonality. Additionally, cell apoptosis after PDGF-D knockdown was measured by Annexin V/ Prodium Iodide staining, and cell migration was detected by trans-well assay. Survival rate and tumor size were measured by nude mice transplantation. RESULTS: The MDA-MB-231 and SK-BR-3 cell lines showed higher PDGF-D expression than the MCF7 cell lines (P<.05). After the PDGF-D gene was silenced, the growth and colony forming abilitys ignificantly decreased (P<.05) together with the induction of apoptosis in MDA-MB-231 cells (P<.05). Moreover, MDA-MB-231 cells with PDGF-D silencing showed significantly diminished aggressive migration and invasion potential compared to other cells (P<.05). In vivo experiments also indicated that PDGF-D silencing inhibited tumor growth and improved the survival rate of tumor-bearing mice. CONCLUSION: Downregulation of PDGF-D had dramatic effects on breast cancer cell proliferation, apoptosis and migration, which indicates that it plays an important role in breast cancer development and progression.

Cross-talk among AFAP1-AS1, ACVR1 and microRNA-384 regulates the stemness of pancreatic cancer cells and tumorigenicity in nude mice.

BACKGROUND: Pancreatic cancer (PC) represents one of the most aggressive forms of cancer. The role of long non-coding RNAs (lncRNAs) has been highlighted in various malignancies including PC. The aim of the present study was to investigate the effects associated with actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1) on the progression of PC and the underlying mechanism. METHODS: Microarray-based gene expression profiling of PC was performed to identify PC-related lncRNAs, after which the expression of AFAP1-AS1 and cancer stem cell (CSC) markers in PC tissues and cells were determined accordingly. The potential microRNA-384 (miR-384) capable of binding to AFAP1-AS1, in addition to its ability to regulate activin receptor A type I (ACVR1) were analyzed. In order to investigate the effect of the AFAP1-AS1/miR-384/ACVR1 axis on self-renewal ability, tumorigenicity, invasion, migration and stemness of PC cells, shRNA-AFAP1-AS1, miR-384 mimic and inhibitor were cloned into cells. RESULTS: High expression of AFAP1-AS1 and ACVR1 with low expression of miR-384 were detected in PC tissues. ACVR1 was determined to be down-regulated when miR-384 was overexpressed, while the inhibition of AFAP1-AS1 decreased its ability to binding competitively to miR-384, resulting in the down-regulation of ACVR1 and enhancing miR-384 expression, ultimately inhibiting the progression of PC. The knockdown of AFAP1-AS1 or overexpression of miR-384 was confirmed to impair PC cell self-renewal ability, tumorigenicity, invasion, migration and stemness. CONCLUSIONS: Taken together, AFAP1-AS1 functions as an endogenous RNA by competitively binding to miR-384 to regulate ACVR1, thus conferring inhibitory effects on PC cell stemness and tumorigenicity.

Factors associated with mortality risk for malignant colonic obstruction in elderly patients.

BACKGROUND: Acute colonic obstruction is the most common complication of colorectal cancer (CRC) in elderly patients. Medical treatment has been associated with higher perioperative morbidity and mortality rates. There is a need for identification of elderly CRC patients who will do poorly so that results can be improved. The purpose of this study is to assess the 30-day outcome of elderly patients undergoing malignant colonic obstruction procedures and identify the associated factors of mortality. METHODS: A review of 233 elderly patients who received medical procedures for malignant colonic obstruction between April 2000 and April 2012 was conducted. Data regarding clinical variables, surgical procedures and outcomes, complications, and mortality were studied. Univariate and logistic regression analyses were performed on mortality risk factors. RESULTS: Patients had a mean age of 78.2 years (range 70-95). A total of 126 (54.1%) patients were classified ASA III and above. Eighty (34.3%) patients had right-sided colonic obstruction. In the 153 (65.7%) patients with left-sided colonic obstruction, 40 patients received self-expandable metallic stent (SEMS) treatment and 193 patients received surgery. A total of 62.2% (n = 145) patients had post operation complications. The overall 30-day mortality was 24.5% (n = 57). ASA grading, peritonitis and Dukes staging were independent risk factors for mortality. CONCLUSIONS: Medical procedures in elderly patients with malignant colonic obstruction are associated with significant complications and mortality. Identifying these high-risk patients and treating promptly may improve outcomes. SEMS treatment provides a useful alternative to surgical intervention.

Quantitative assessment of the influence of cytochrome P450 2C19 gene polymorphisms and digestive tract cancer risk.

Cytochrome P450 (CYP) 2C19 metabolizes many promutagens and procarcinogens to biologically active metabolites, which strongly promote proliferation of cancer cells in vitro and in vivo. The CYP2C19 gene exhibits several genetic polymorphisms that are thought to play a major role in inter-individual variability in drug response, drug-xenobiotic interactions, and in cancer susceptibility. Two polymorphisms of the CYP2C19 gene (CYP2C19*2, CYP2C19*3) which was associated with reduced enzyme activity have been investigated extensively digestive tract cancer; however, these studies have yielded contradictory results. To clarify this inconsistency, we performed this meta-analysis including 15 case-control studies with a total of 3,252 cases and 6,269 controls. Overall, we found significant association between CYP2C19*2 and digestive tract cancer (OR = 1.27, 95 % CI, 1.07-1.51, P = 0.007) while no significant results were found for CYP2C19*3. Potential sources of heterogeneity including cancer types, ethnicity, source of control, and sample size of study were assessed. In the subgroup analyses by cancer types, significant association was detected only in esophagus cancer for CYP2C19*2. When stratified by ethnicity, significantly increased risks were found for the CYP2C19*2 polymorphism among Asians. This meta-analysis demonstrated that the CYP2C19*2 polymorphism is a risk factor for developing digestive tract cancer. However, additional very large-scale studies are warranted to provide conclusive evidence on the effects of the CYP2C19 gene on risk of digestive tract cancer.

Decreasing pancreatic leak after distal pancreatectomy: bovine pericardium wrapping stump in a porcine model.

BACKGROUND: Despite marked improvements in pancreatic surgery, the high incidence and morbidity of pancreatic leak after resection has remained unchanged. The current study investigated the safety and efficacy of bovine pericardium wrapping stump after distal pancreatectomy in a porcine model. METHODS: Thirty-two swine were randomly assigned to control and experiment groups to undergo conventional scalpel transection with single hand-sewn closure of the pancreatic remnant (control) or bovine pericardium wrapping stump combined with hand-sewn closure (experiment). Closed-suction drainage was collected and measured daily. Animals were necropsied at 3 weeks postoperatively, and the pancreatic remnants were examined for histology. Primary end points were the development of a pancreatic fistula defined as greater than threefold drain/serum amylase after the 3rd postoperative day, and the presence of undrained amylase-rich fluid collections/abscess. RESULTS: The incidence of pancreatic leak in the wrapping group was 6.3 versus 46.7% in the control group (p < 0.05). The amount of drainage fluid was higher in the control group than the experiment group during the postoperative days. There were no differences in operative time or other clinical parameters measured. No other significant differences were found in macroscopic changes between groups at reexploration. Histological examination demonstrated focal, chronic inflammation with necrosis in all animals. CONCLUSIONS: Bovine pericardium wrapping stump effectively reduced the incidence of pancreatic leakage after the distal pancreatectomy.