Chronic atrophic gastritis is a progressive disease: analysis of medical reports from Shanghai (1985-2009)

<p><b>INTRODUCTION</b>We aimed to examine the turnover of chronic atrophic gastritis (CAG) pathologically and endoscopically and explore its potential causes.</p><p><b>METHODS</b>A retrospective analysis was conducted of prospective data collected from 1,592 patients who underwent gastroscopy three times or more during the period 1985-2009 at Renji Hospital, Shanghai, China. Pathological and endoscopic findings were analysed. Data collected included gender, age, length of follow-up period, family history, past medical history, history of Helicobacter (H.) pylori infection, drug history for the use of proton pump inhibitors (PPIs), antacids and non-steroidal anti-inflammatory drugs [NSAIDs], and lifestyle history, including the patients' eating habits.</p><p><b>RESULTS</b>23 (1.44%) patients presented with gastric cancers resulting from CAG and 349 (21.92%) patients had dysplasia. Pathological and endoscopic findings suggested that the proportion of patients with worsening gastric mucosa during the atrophic and intestinal metaplasia (IM) phases was over 35% with increasing age. Gastric mucosa was found to be pathologically aggravated by carbonated drinks and fast food, and pathologically degenerated by H. pylori infection. Smoking deteriorated the gastric mucosa. Side dishes of vegetables may benefit the gastric mucosa even in the atrophic and IM phases.</p><p><b>CONCLUSION</b>Our findings support the consensus that CAG is a progressive disease. Potential factors that were found to affect the state of the gastric mucosa in our patient group were gender, H. pylori infection, use of PPIs or NSAIDs, and intake of vegetable side dishes, spicy food, carbonated drinks and fast food.</p>

Recent progress on miRNAs in the pathogenesis of colon cancer / 中华医学遗传学杂志

microRNAs (miRNAs) are endogenous, small noncoding RNA molecules discovered in animals, plants and viruses. They play a critical role in developmental and physiological processes and are implicated in the pathogenesis of many human cancers. Presently, human cancer, including colorectal cancer, is recognized as both a genetic and epigenetic disease. Changes induced by miRNAs are considered as epigenetic changes. Experiments were largely performed to analyze the colorectal microRNAome and bio-networking involving miRNAs. This review focuses on recent advances in colorectal miRNA expression profiles. Further, we discuss the regulatory network of miRNAs in the initiation and carcinogenesis of colon cancer in order to open up an avenue of anticancer therapy based on the epigenetic regulation by miRNAs.

The relationship of mTOR signaling pathway and histone acetylation in human gastric cancer cell lines / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To evaluate the relationship between mammalian target of rapamycin (mTOR) signaling pathway and histone acetylation in cell survival, cell cycle, gene expression and protein level on human gastric cancer cells.</p><p><b>METHODS</b>Human gastric cancer cell lines, MKN45 and SGC7901 were treated with trichostatin A, rapamycin and/or LY294002, a PI3K inhibitor. Cell viability was analyzed by methylthiazolyl tetrazolium. Cell cycle distribution was evaluated by flow cytometry. The transcription level of p21(WAF1) gene was detected by using real-time polymerase chain reaction. Proteins were detected by Western blotting.</p><p><b>RESULTS</b>Cell viability remarkably reduced after treatment by more than two drugs (P< 0.01). Through flow cytometry assessment, MKN45 cells were arrested in G2 phase (P< 0.05), while SGC7901 cells were in G2 or G1 phase (P< 0.05) whether treated with single or more than two drugs. The expression of p21(WAF1) mRNA was remarkably increased in the gastric cancer cells treated with conjoined drugs (P< 0.01). Phosphorylation of Akt, p70S6K and 4E-BP1 was significantly reduced in cells treated with conjoined drugs (P< 0.01). And histone acetylation of H4/H3 was also increased in cells treated with conjoined drugs (P< 0.01).</p><p><b>CONCLUSION</b>mTOR singnaling pathway has an important relationship with histone acetylation in gastric cancer cell lines. There is a co-effect of mTOR inhibitor and histone deacetylase inhibitor on gastric cancer cells.</p>

Synergistic effect of rapamycin (RPM) and PD98059 on cell cycle and mTOR signal transduction in human colorectal cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the synergistic effect of rapamycin (RPM) and PD98059 on human colorectal cancer cells and its potential mechanisms.</p><p><b>METHODS</b>Three human colorectal cancer cell lines SW480, HCT116 and HT29 were treated with RPM 10 nmol/L, PD98059 (10 micromol/L, 20 micromol/L, 40 micromol/L, 50 micromol/L), or RPM plus PD98059, respectively, and the sensitivity was analyzed by MTT assay. The cell cycle progression was evaluated by flow cytometry. Western blotting analysis was performed to examine the total and phosphorylated levels of mammalian target of rapamycin (mTOR) and its downstream translational signaling intermediates, 70 kDa ribosomal protein S6 kinase (p70s6k) and eukaryotic initiation factor 4E-binding protein 1 (4E-BP1).</p><p><b>RESULTS</b>Both RPM and PD98059 could inhibit viability of the three cell lines. The anti-proliferative effect of PD98059 exhibited a time/dose dependent manner and was strengthen by RPM. All the treatment with RPM, PD98059, and RPM + PD98059 induced arrest of cell cycle, although the arrest was confined at different cell cycle phases. In addition to their effect on proliferation and cell cycle, both inhibitors also reduced phosphorylation levels of mTOR, p70s6k, and 4E-BP1, as well as total 4E-BP1 levels in SW480 and HCT116 cells. That effect was reinforced when cells were treated with RPM plus PD98059 simultaneously, whereas total protein levels of mTOR and p70s6k remained unchanged.</p><p><b>CONCLUSION</b>RPM and PD98059 inhibit proliferation of colorectal cancer cells synergistically, and induce cell cycle arrest. The modulation of mammalian target of rapamycin signaling pathway is involved in its potential mechanisms.</p>

Effect of magnesium isoglycyrrhizinate on the proliferation and oxidative stress of rat hepatic stellate cells in vitro / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To investigate the effect of magnesium isoglycyrrhizinate on the proliferation and oxidative stress of rat hepatic stellate cells (HSCs).</p><p><b>METHODS</b>The effect of various concentrations of maganesium isoglycyrrhizinate on the proliferation of primary rat HSCs and HSCs strains were measured by making cell growth curves and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphennylterazolium bromide (MTT) colorimetric assay. Morphological changes of the rat HSCs were also studied. After rat HSCs were incubated with various concentrations of maganesium isoglycyrrhizinate and ferric nitrilotriacetate (Fe-NTA) for 24 hours, the activity of superoxide dismutase (SOD) and contents of malondialdehyde (MDA) in supernates were measured to observe the effect of magnesium isoglycyrrhizinate on the oxidative stress of rat HSCs.</p><p><b>RESULTS</b>Compared with the control group, the proliferation of rat HSCs was significantly inhibited when the concentration of magnesium isoglycyrrhizinate in the medium reached a certain level range. In the oxidative stress induced by Fe-NTA, magnesium isoglycyrrhizinate, within a certain strength range, obviously enhanced the activity of SOD and decreased the contents of MDA in supernates of rat HSCs culture media.</p><p><b>CONCLUSIONS</b>Magnesium isoglycyrrhizinate could significantly inhibit the proliferation of rat HSCs and it, within a certain strength range, exert protective effects in the oxidative stress induced by Fe-NTA.</p>

The effect of PKC-delta inhibitor Rottlerin on human colon cancer cell line SW1116 and its mechanism / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the effect of PKC-delta inhibitor Rottlerin on human colon cancer cells and its mechanism.</p><p><b>METHODS</b>Human colon cancer cell line SW1116 cells were treated with Rottlerin. The transcriptional level of DNA methyltransferase (Dnmt)1, Dnmt3a and Dnmt3b was detected by real-time RT-PCR. Cell cycle distribution was evaluated by flow cytometry (FCM). In addition, cellular morphological changes were examined by light microscopy.</p><p><b>RESULTS</b>PKC-delta inhibitor decreased the expression of Dnmt1, Dnmt3a mRNA, up-regulated APC, p21(WAF1) and p16(INK4A) mRNA. Demonstarted by flow cytometry, Rottlerin increased the percentage of cell cycle G0/G1 phase cell numbers (P = 0.02) and decreased the percentage of cell cycle G2/M phase cell numbers (P = 0.01). Remarkable changes of cellular morphology were observed under light microscope: The volume and cytoplasm of cells treated with Rottlerin were increased. The cell contour was not very clear, and mitotic figures were less frequently seen.</p><p><b>CONCLUSION</b>PKC-delta inhibitor Rottlerin inhibites cell division and proliferation of the colon cancer SW1116 cells through regulating DNA methylation and blocking the signaling pathway of mitogen-activated protein kinase (MAPK).</p>

5-Aza-2'-deoxycitydine induces demethylation and up-regulates transcription of p16INK4A gene in human gastric cancer cell lines / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>To investigate the effects of DNA methylation on the expression of tumor-associated genes and the cell cycle in human gastric cancer cells.</p><p><b>METHODS</b>Two gastric cancer cell lines (MKN-45 and HGC-27) were treated with DNA methyltransferase (DNMT) inhibitor, 5-aza-2'-deoxycytidine (5-aza-dC). The expressions of p16INK4A, p21WAF1, p53, p73, c-Ha-ras and c-myc genes mRNA were detected by using reverse transcription PCR (RT-PCR). DNA methylation status of p16INK4A gene promoter was assayed by bisulfite modification and sequencing. The cell cycle was analyzed by using flow cytometry (FCM).</p><p><b>RESULTS</b>5-aza-dC induced the demethylation of p16INK4A gene promoter. The expression of p16INK4A mRNA was obviously up-regulated by treatment with 10 micro mol/L (MKN-45 cells) or 5 micro mol/L (HGC-27 cells) of 5-aza-dC for 24 hours. However, 5-aza-dC treatment failed to regulate the expressions of p21WAF1, p53, p73, c-Ha-ras and c-myc genes in MKN-45 and HGC-27 cells. Furthermore, 5-aza-dC induced the cell cycle arrest in G1 phase in HGC-27 cell, but not in MKN-45 cell.</p><p><b>CONCLUSIONS</b>DNA methylation regulates the transcription of p16INK4A but not p21WAF1 and proto-oncogenes in human gastric cancer cell lines MKN-45 and HGC-27.</p>

Effect of eukaryotic expression plasmid containing methylenetetrahydrofolate reductase gene on transcriptional level of tumor-related genes in human gastric cancer cell line / 中华消化杂志

Objective To analyze the effect of eukaryotic plasmids containing wild (sense) or anti- sense methylenetetrahydrofolate reductase (MTHFR) gene on cell viability and transcription level of tumor related genes in human gastric cancer cell line.Methods Human gastric cancer cell line MKN-45 was cultured.Recombinant plasmids containing wild MTHFR (W) or antisense MTHFR (A) gene, pCMV-W and pCMV-A,were constructed.Then pCMV-W,pCMV-A and pCMV blank plasmid were transfected into MKN45 cells respectively by using lipofect.Cell viability was analyzed by 3-(4,5-bime- thylthiazolyl-2)-2,5-diphenyhetrazolium dromide(MTT).The transcription levels of Dnmt 1,c-myc, p21~(WAF1) and hMLH1 genes were detected by real-time polymerase chain reaction(PCR).Results Cell vi- ability remarkably increased in those transfected with wild MTHFR (P＜0.01),which was contrary to those transfected with antisense MTHFR(P＜0.01).The expression of those tumor related genes mRNAs were all remarkably decreased in the MKN45-W cells in comparison with those in the MKN45-pCMV cells.No significant difference in the expressions of those tumor related genes mRNAs were found between the MKN45 cells transfected with pCMV-A and blank pCMV.Conclusion MTHFR influences cell viability and the expres- sion level of tumor related genes in human gastric cancer cell line MKN45.