Abstract?AIM: To compare the changes in epithelial thickness profile following TransPRK and Epi-LASIK for myopia.? METHODS: In this prospective non -randomized controlled study, 76 right eyes of 76 myopic patients with the spherical equivalent refraction -1.25 to -6.00D were included under the informed consent. The eyes were divided into TransPRK group for 43 eyes and Epi-LASIK group for 33 eyes. Epithelial thickness was measured using spectral-domain optical coherence tomography at different corneal zones ( central, 2mm; paracentral, 2-5mm;and mid-peripheral, 5-6mm) preoperatively and at 1, 3, and 6mo postoperatively. The results were compared between the two groups.?RESULTS: The epithelium were thicker at 3 and 6mo after surgery compared to preoperative measurements in the two groups (all P<0.05).In TransPRK group, the epithelial thickness at 3 and 6mo demonstrated a negative meniscus-like lenticular pattern with lesser thickening centrally and progressively great thickening centrifugally (F3mo =-2.687,P=0.027;F6mo =-2.908,P=0.000).No statistically significant change was detected among the three zones in Epi-LASIK group (F=1.365, P=0.237). The epithelial thickness was thicker in the TransPRK group compared to the Epi-LASIK group mid-peripherally ( P<0.05) .? CONCLUSION: Significant epithelial thickening was observed after TransPRK and Epi-LASIK.It was showed a lenticular change with more thickening mid-peripherally after TransPRK than Epi -LASIK. Wound healing and inflammation may account for differences in the effect on epithelial thickness change by both surgeries.

Background and purpose:Remarkable advances have been made in cancer chemotherapy by developing new anticancer drugs and therapy strategies.However,multidrug resistance in human cancers remains a major clinical challenge for cancer treatment.Attempts in several clinical studies to reverse multidrug resistance protein (MDR) by using MDR modulators have not yet generated promising results.Our aim was to explored the mechanism of reversal of multidrug resistance in human leukemia K562 cells by PI3-K inhibitor.Methods:Trypanblue dye exclusion method was used to observe the drug sensitivity and the effect of LY294002 on the drug resistance.Western blot to analyze P-gp and p-Akt phenotypes,and flow cytometer was used to measure the intracellular drug accumulation. Results:K562/D induced by DNR was cross resistant to DNR,ADR,VCR and VP16 (Resistance Index:65,52,134 and 50 respectively).DNR induced over-expressions of P-gp and p-Akt in K562/D cells;LY294002 increased the intracellular drug accumulation,and then reversed the drug resistance to DNR,ADR,VCR and VPI6 in K562/D cells(Resistance Index:23,21,63 and 29 respectively),but not in the sensitive cells (K562/S).Conclusion:The multidrug resistance of K562/D cells can be induced by DNR which is related to the P-gp and p-Akt over-expressions, and LY294002 can reverse multidrug resistance in human leukemia cells in vitro via inhibits PI3-K/Akt pathway.

OBJECTIVETo study the effect of RNA interference (RNAi) targeting E6AP on the proliferation and apoptosis of HeLa cells.

METHODSHeLa cells were cultured and divided into 3 groups: blank control group, cells transfected with nonsense siRNA (small interference RNA), and cells transfected with specific E6AP siRNA. The expressions of E6AP mRNA and protein were detected by RT-PCR and Western blot before and after the transfection respectively. Cell proliferation was determined by methylthiazolyl tetrazolium (MTT). The cell apoptosis index was assessed by flow cytometry.

RESULTSUpon treatment with E6AP siRNA for 24, 48 and 72 h, the expression level of E6AP mRNA decreased 33%, 72% and 70% than siRNA treated group. The protein expression levels in 48 h and 72 h E6AP siRNA groups decreased 38%, 59% comparing with those of the nonsense siRNA treated group (P < 0.05). The proliferative capacity of cells transfectd with E6AP siRNA was significantly lower than blank control group (F = 101.38, P < 0.05) and siRNA treated group (F = 38.64, P < 0.05). The apoptosis index of HeLa cells treated with E6AP siRNA was significantly higher than that of the nonsense siRNA (F = 41.48, P < 0.05) and the blank control group (F = 86.36, P < 0.05).

CONCLUSIONSiRNA targeting can effectively suppress the expression levels of E6AP mRNA, corresponding with a proliferation inhibition and an enhanced apoptosis of HeLa cells.

Cell Line, Tumor ; Cell Proliferation ; Female ; Gene Expression Regulation, Neoplastic ; genetics ; Gene Silencing ; HeLa Cells ; Humans ; RNA Interference ; RNA, Small Interfering ; genetics ; pharmacology ; Reverse Transcriptase Polymerase Chain Reaction ; Ubiquitin-Protein Ligases ; antagonists & inhibitors ; metabolism ; Uterine Cervical Neoplasms ; genetics ; metabolism

OBJECTIVEGastric cancer cells are insensitive to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). To sensitize gastric cancer cells to TRAIL, we treated gastric cancer MGC803 cells with TRAIL and cisplatin.

METHODSCell proliferation was measured using MTT assay. Cell apoptosis was determined by flow cytometry. Expression of proteins was analyzed by Western blot. The distribution of lipid rafts and death receptors was analyzed by immunofluorescence microscopy. MGC803 cells were pretreated with 50 mg/L nystatin for 1 h, and followed by the treatment of cisplatin and TRAIL.

RESULTS100 µg/L TRAIL resulted in (8.51 ± 3.45)% inhibition of cell proliferation and caused (3.26 ± 0.89)% cell apoptosis in MGC803 cells. Compared with the treatment with cisplatin alone, treatment with TRAIL (100 µg/L) and cisplatin (8.49 mg/L, IC(50) dose of 24 h) led to a dramatic increase in both inhibition of cell proliferation [(52.58 ± 4.57)% vs. (76.43 ± 5.35)%, P < 0.05] and cell apoptosis [(23.10 ± 3.41)% vs. (42.56 ± 4.11)%, P < 0.05]. Moreover, cleavage of caspase-8 and caspase-3 was detected. TRAIL (100 µg/L) did not induce obvious lipid rafts aggregation and death receptor 4 (DR4) clustering, while cisplatin (8.49 mg/L) significantly promoted the localization of DR4 in aggregated lipid rafts. Pretreatment with 50 mg/L nystatin, a cholesterol-sequestering agent, triggered (3.66 ± 0.52)% cell apoptosis after 24 h. Pretreatment with nystatin for 1 h before the addition of 8.49 mg/L cisplatin for 24 h caused a decreased tendency to cell apoptosis [(25.74 ± 3.28)% vs. (22.76 ± 2.97)%]. While, pretreatment with nystatin before the addition of cisplatin and TRAIL, the proportion of apoptotic cells decreased from (43.16 ± 4.26)% to (31.52 ± 3.99)% (P < 0.05).

CONCLUSIONCisplatin enhances TRAIL-induced apoptosis in gastric cancer MGC803 cells through clustering death receptors into lipid rafts.

Antineoplastic Agents ; administration & dosage ; pharmacology ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cisplatin ; administration & dosage ; pharmacology ; Dose-Response Relationship, Drug ; Humans ; Membrane Microdomains ; metabolism ; Nystatin ; pharmacology ; Receptors, TNF-Related Apoptosis-Inducing Ligand ; metabolism ; Stomach Neoplasms ; metabolism ; pathology ; TNF-Related Apoptosis-Inducing Ligand ; pharmacology

BACKGROUND AND OBJECTIVEc-Cbl and Cbl-b are two ubiquitous members of the Casitas B-lineage lymphoma (Cbl) family, which play important roles in the downregulation of epidermal growth factor receptor (EGFR) by acting as E3 ubiquitin ligases and multiadaptor proteins. This study investigated the expression of c-Cbl, Cbl-b, and EGFR in gastric carcinoma and its clinical significance.

METHODSThe expressions of c-Cbl, Cbl-b, and EGFR were detected by immunohistochemistry using tissue microarrays consisting of 124 specimens of gastric carcinoma and 16 specimens of normal gastric mucosa. The relationship between the expressions of c-Cbl, Cbl-b, and EGFR and clinicopathologic factors of gastric carcinoma were analyzed statistically.

RESULTSThe positive rates of c-Cbl, Cbl-b, and EGFR were higher in the gastric carcinoma group than in the normal group (71.0% vs. 18.0%, P<0.01; 82.3% vs. 25.0%, P<0.01; 56.5% vs. 12.5%, P<0.01, respectively). The expression of c-Cbl was positively correlated with depth of invasion (r=0.219, P=0.015), and TNM staging (r=0.266, P=0.003). The expression of Cbl-b was positively correlated with lymph node metastasis (r=0.190, P<0.034) and TNM staging (r=0.298, P<0.001). The expression of EGFR was positively correlated with depth of invasion (r=0.286, P<0.001) and TNM staging (r=0.362, P=0.000). The expression of both c-Cbl and Cbl-b was positively correlated with EGFR (r=0.241, P=0.007; r=0.183, P=0.042, respectively). Synchronous strong-positive expressions of c-Cbl, Cbl-b, and EGFR were observed in 27 specimens of gastric carcinoma, most of which were at advanced stage.

CONCLUSIONSOverexpressions of c-Cbl, Cbl-b, and EGFR are closely related to the invasion and progression of gastric carcinoma. c-Cbl and Cbl-b may serve as novel molecular markers for gastric carcinoma.

Adaptor Proteins, Signal Transducing ; metabolism ; Adenocarcinoma ; metabolism ; pathology ; Adult ; Aged ; Aged, 80 and over ; Biomarkers, Tumor ; metabolism ; Disease Progression ; Female ; Humans ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoplasm Invasiveness ; Neoplasm Staging ; Proto-Oncogene Proteins c-cbl ; metabolism ; Receptor, Epidermal Growth Factor ; metabolism ; Stomach Neoplasms ; metabolism ; pathology ; Young Adult

Objective To evaluate the changes in epithelial thickness profile and its relationship with diopter following small incision lenticule extraction (SMILE) for moderate and high myopia.Methods Together 46 myopia or myopic astigmatism (92 eyes) who underwent SMILE were included under the informed consent from January 2016 to March 2017 and were decided into 2 groups according to the diopter:moderate myopia group (58 eyes)and high myopia group (34 eyes).Epithelial thickness profile was measured using spectral-domain optical coherence tomography at different corneal zones (0-2 mm,＞ 2-5 mm and ＞ 5-6 mm cornea) preoperatively before surgery and 1 month and 6 months after surgery for observing the changes in epithelial thickness and its correction with diopter.Results The mean epithelial thickness in the central zone was (55.68 ± 3.61) μm before surgery,and,6 months after surgery,it was thickened by (3.85-±3.99),(3.46 ±3.29) and (2.85 ±3.18) μm in the 0-2 mm,＞2-5 mum and ＞5-6 mm cornea respectively,and the difference was statistically significant among the three zones (P ＜ 0.01).After surgery for 6 months,the epithelial thickness in the high myopia group was thickened more obviously compared with the moderate myopia group (t =1.440,P =-0.047).And no correlation was found between changes in the epithelial thickness at 0-2 mm cornea and diopter after surgery(moderate myopia group:r =0.219,P=0.633;high myopia group:r =0.197,P =0.585).Conclusion Significant epithelial thickening was observed after SMILE,presenting the thickened epithelium.The higher the diopter was,the more thickened the epithelium was.The epithelial changes does not appear to affect the diopter after SMILE.

OBJECTIVETo investigate the role of multidrug resistant protein 2 (MRP2) and glutathione (GSH) cotransport system in hepatic arsenic metabolism in rats.

METHODSThirty healthy Wistar rats were divided randomizedly into five groups. The first group was the control group and the rats in this group were administered with normal saline. In the second, third and fourth group the rats were administered with 4, 10 and 20 mg As(+)3/kg BW of sodium arsenite respectively every other day for two weeks. The fifth group was the benzene-soluble organics (BSO) intervention group and in this group the rats were administered with 2 mmol/kg BW BSO intraperitoneally every day three days before the end of the experiment. The other treatment was the same as in other groups. All rats were sacrificed two weeks after the treatments. Arsenic contents in bile, liver and blood were detected by atomic absorption spectroscopy (AAS), and the expression of MRP2 in the membrane of hepatocyte was determined by Western-blot analysis.

RESULTSThe level of total arsenic (including organic arsenic and inorganic arsenic) in bile, liver and blood in all three different dose groups was higher than those in the control groups (P < 0.05). Arsenic levels of bile and liver were increased with intragastric arsenic dose. Blood arsenic levels were not significantly different in three different dose groups. Expression of hepatic MRP2 was increased with intragastric arsenic concentration. A positive correlation between biliary arsenic concentration and MRP2 levels was found in liver (r = 0.986, P < 0.05). For the rats pretreated with BSO, the biliary arsenic was significantly higher than that in the control group but lower than that in the high dose group; the liver and blood arsenic was higher than that in the control group and in the high dose group. Expression of MRP2 pretreated with BSO was decreased.

CONCLUSIONSodium arsenite can induce expression of MRP2 and the up-regulation of MRP2 may play an important role in the bile secretion of arsenite and its metabolites. The function of MRP2 for transportation of arsenic and its metabolites is associated with the intracellular GSH level. BSO inhibits the synthesis of GSH, which weakens the function of the MRP2-GSH cotransport system and makes the liver arsenic increased.

Animals ; Arsenic ; pharmacokinetics ; Arsenic Poisoning ; metabolism ; Bile ; metabolism ; Female ; Glutathione ; biosynthesis ; Liver ; metabolism ; Male ; Membrane Transport Proteins ; biosynthesis ; Multidrug Resistance-Associated Proteins ; biosynthesis ; Random Allocation ; Rats ; Up-Regulation

Previous study revealed that bufalin can inhibit proliferation, and induce apoptosis in some human cancer cell lines. However, the mechanism of its anticancer effect has not been fully understood. The present study was designed to investigate the effects of bufalin-induced apoptosis on Bcl-2 and PKC in human leukemic HL-60 cells. The cell viability was determined by trypan blue dye exclusion. The apoptosis was detected by morphology, flow cytometry and DNA agarose gel electrophoresis. The expressions of Bcl-2 and PKC were analyzed by Western blot, and activity of PKC was assayed by [gamma-(32)P] isotope incorporation method. The results showed as follows: (1) proliferation of HL-60 cells was inhibited by bufalin and the IC(50) at 24, 48, 72 hours were (25.8 +/- 2.1), (8.0 +/- 1.2) and (2.3 +/- 0.3) nmol/L, respectively. (2) apoptosis of HL-60 cells was induced when the cells were treated with bufalin at concentration of 50 nmol/L for 24 hours. (3) compared with control, treatment with bufalin at concentration of 50 nmol/L for 6 - 24 hours resulted in downregulation of protein expression, decrease of phosphorylation, and cleavage of Bcl-2, simultaneously. (4) the activity of total PKC was unchanged when HL-60 cells were exposed to 1 - 100 nmol/L bufalin for 30 minutes, but PKCbetaII underwent translocation from cytosol to membrane. It is concluded that apoptosis induced by bufalin is associated with downregulation of protein expression, dephosphorylation, and cleavage of Bcl-2 in HL-60 cells.
Apoptosis ; drug effects ; Bufanolides ; pharmacology ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; HL-60 Cells ; Humans ; Materia Medica ; pharmacology ; Phosphorylation ; Protein Kinase C ; biosynthesis ; genetics ; Proto-Oncogene Proteins c-bcl-2 ; biosynthesis ; genetics

Oxaliplatin-based chemotherapy is used for treating gastric cancer. Autophagy has been extensively implicated in cancer cells; however, its function is not fully understood. Our study aimed to determine if oxaliplatin induce autophagy in gastric cancer MGC803 cells and to assess the effect of autophagy on apoptosis induced by oxaliplatin. MGC803 cells were cultured with oxaliplatin. Cell proliferation was measured using MTT assay, and apoptosis was determined by flow cytometry. Protein expression was detected by Western blot. Autophagy was observed using fluorescent microscopy. Our results showed that the rate of apoptosis was 9.73% and 16.36% when MGC803 cells were treated with 5 and 20 μg/mL oxaliplatin for 24 h, respectively. In addition, caspase activation and poly ADP-ribose polymerase (PARP) cleavage were detected. Furthermore, when MGC803 cells were treated with oxaliplatin for 24 h, an accumulation of punctate LC3 and an increase of LC3-II protein were also detected, indicating the activation of autophagy. Phosphorylation of Akt and mTOR were inhibited by oxaliplatin. Compared to oxaliplatin alone, the combination of autophagy inhibitor chlorochine and oxaliplatin significantly enhanced the inhibition of cell proliferation and the induction of cell apoptosis. In conclusion, oxaliplatin-induced protective autophagy partially prevents apoptosis in gastric cancer MGC803 cells. The combination of autophagy inhibitor and oxaliplatin may be a new therapeutic option for gastric cancer.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Autophagy ; drug effects ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Organoplatinum Compounds ; pharmacology ; Phosphatidylinositol 3-Kinase ; metabolism ; Poly(ADP-ribose) Polymerases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Signal Transduction ; drug effects ; Stomach Neoplasms ; metabolism ; pathology ; TOR Serine-Threonine Kinases ; metabolism

The study was aimed to explore the mechanism of SYK and CBL family of ubiquitin ligases in Bufalin-induced HL-60 cells apoptosis. Cell viability was tested by trypan blue staining and apoptosis was detected by using flow cytometry. The expressions of CBL and CBL-b and the phosphorylation of SYK were detected by using immunoprecipitation and Western blot. The results showed that Bufalin inhibited HL-60 cell proliferation in time- and dose-dependent manners. IC(50) of suppressing cell viability at 24, 48 and 72 hours were about 26.3, 7.8 and 2.0 nmol/L respectively. The high dose of bufalin already induced apoptosis of HL-60 cells at 8 hours. SYK was quickly phosphorylated, and the expressions of CBL and CBL-b were down-regulated after treatment with Bufalin. It is concluded that SYK activation and CBL protein down-regulation may be involved in Bufalin-induced HL-60 cell apoptosis.
Apoptosis ; drug effects ; Bufanolides ; pharmacology ; Cell Proliferation ; drug effects ; Down-Regulation ; Gene Expression Regulation, Leukemic ; HL-60 Cells ; Humans ; Intracellular Signaling Peptides and Proteins ; metabolism ; Protein-Tyrosine Kinases ; metabolism ; Proto-Oncogene Proteins c-cbl ; metabolism ; Signal Transduction ; Syk Kinase