OBJECTIVETo determine the effect of type I transmembrane protein (IRE1alpha) deletions on the cell cycle of human periodontal ligament fibroblasts (hPDLFs) cells.

METHODSBased on the IRE1alpha deletions, a full-length model was successfully constructed. Moreover, overlapping polymerase chain reaction mutagenesis facilitated the establishment of two deletion mutants of IREla (pD-Kinase, pD-Rnase). The full-length model and two mutant eukaryotic expression vectors were transfected into hPDLFs cells. Western blot analysis was performed to identify the expression in the cells. The changes in the cell cycle of hPDLFS cells were detected by flow cytometry (FCM).

RESULTSThe two deletion mutants of IRE1alpha with eukaryotic expression vectors were successfully constructed and correctly expressed in hPDLFs cells based on Western blot analysis. Under stress conditions, the FCM assay showed that cell percentage of S phases increased, whereas that of G1 phases decreased in the IRE1alpha group (P < 0.05) compared with the control group of tunicamycin (TM) treatment. Moreover, the cell percentage of the S phases decreased, whereas that of the G1 phases increased in the D-Rnase group (P < 0.05) compared with the control. The deletion mutant D-Kinase had no influence on hPDLFS cell proliferation and cycle (P>0.05).

CONCLUSIONUnder stress conditions, IRE1alpha can improve the cell cycle of hPDLFs cells from the G1 to the S phase. The deletion mutant D-Rnase cause hPDLFs cell growth arrest at the G1 phase, whereas deletion mutant D-Kinase has no significant effect.

Cell Cycle ; Cell Proliferation ; Endoribonucleases ; Fibroblasts ; Humans ; Periodontal Ligament ; Protein-Serine-Threonine Kinases ; Transfection

Objective To determine the effect of type Ⅰ transmembrane protein (IRE1α) deletions on the cell cycle of human periodontal ligament fibroblasts (hPDLFs) cells. Methods Based on the IRE1α deletions, a full-length model was successfully constructed. Moreover, overlapping polymerase chain reaction mutagenesis facilitated the establishment of two deletion mutants of IRE1α (pD-Kinase, pD-Rnase). The full-length model and two mutant eukaryotic expression vectors were transfected into hPDLFs cells. Western blot analysis was performed to identify the expression in the cells. The changes in the cell cycle of hPDLFS cells were detected by flow cytometry (FCM). Results The two deletion mutants of IRE1α with eukaryotic expression vectors were successfully constructed and correctly expressed in hPDLFs cells based on Western blot analysis. Under stress conditions, the FCM assay showed that cell percentage of S phases increased, whereas that of G1 phases decreased in the IRE1α group (P<0.05) compared with the control group of tunicamycin (TM) treatment. Moreover, the cell percentage of the S phases decreased, whereas that of the G1 phases increased in the D-Rnase group (P<0.05) compared with the control. The deletion mutant D-Kinase had no influence on hPDLFS cell proliferation and cycle (P>0.05). Conclusion Under stress conditions, IRE1α can improve the cell cycle of hPDLFs cells from the G1 to the S phase. The deletion mutant D-Rnase cause hPDLFs cell growth arrest at the G1 phase, whereas deletion mutant D-Kinase has no significant effect.

OBJECTIVETo summarize the treatment status of gastric gastrointestinal stromal tumor (GIST) in Shandong province,by analyzing the clinicopathological features and prognostic factors.

METHODSClinicopathological and follow-up data of 1 165 patients with gastric GIST between January 2000 and December 2013 from 23 tertiary referral hospitals in Shandong Province were collected to establish a database. The risk stratification of all cases was performed according to the National Institutes of Health(NIH) criteria proposed in 2008. Kaplan-Meier method was used to calculate the survival rate. Log-rank test and Cox regression model were used for univariate and multivariate prognostic analyses.

RESULTSAmong 1 165 cases of gastric GIST, 557 were male and 608 were female. The median age of onset was 60 (range 15-89) years. Primary tumors were located in the gastric fundus and cardia in 623 cases(53.5%), gastric body in 346 cases(29.7%), gastric antrum in 196 cases(16.8%). All the cases underwent resection of tumors, including endoscopic resection (n=106), local resection (n=589), subtotal gastrectomy(n=399), and total gastrectomy(n=72). Based on the NIH risk stratification, there were 256 cases (22.0%) at very low risk, 435 (37.3%) at low risk, 251 cases (21.5%) at intermediate risk, and 223 cases (19.1%) at high risk. A total of 1 116 cases(95.8%) were followed up and the median follow-up period was 40 (range, 1-60) months. During the period, 337 patients relapsed and the median time to recurrence was 34 (range 1-60) months. The 1-, 3-, and 5-year survival rates were 98.6%, 86.1% and 73.4%, respectively. The 5-year survival rates of patients at very low, low, intermediate, and high risk were 93.1%, 85.8%, 63.0% and 42.3% respectively, with a statistically significant difference (P=0.000). Multivariate analysis showed that primary tumor site (RR=0.580, 95%CI:0.402-0.835), tumor size (RR=0.450, 95%CI:0.266-0.760), intraoperative tumor rupture(RR=0.557, 95%CI:0.336-0.924), risk classification (RR=0.309, 95%CI:0.164-0.580) and the use of imatinib after surgery (RR=1.993, 95%CI:1.350-2.922) were independent prognostic factors.

CONCLUSIONSThe choice of surgical procedure for gastric GIST patients should be based on tumor size. All the routine procedures including endoscopic resection, local excision, subtotal gastrectomy and total gastrectomy can obtain satisfactory curative outcomes. NIH classification has a high value for the prediction of prognosis. Primary tumor site, tumor size, intraoperative tumor rupture, risk stratification and postoperative use of imatinib are independent prognostic factors in gastric GIST patients.