Streptococcus anginosus in the development and treatment of precancerous lesions of gastric cancer

The microbiota is strongly association with cancer.Studies have shown significant differences in the gastric microbiota between patients with gastric cancer(GC)patients and noncancer patients,suggesting that the microbiota may play a role in the development of GC.Although Helicobacter pylori(H.pylori)infection is widely recognized as a primary risk factor for GC,recent studies based on microbiota sequencing technology have revealed that non-H.pylori microbes also have a significant impact on GC.A recent study discovered that Streptococcus anginosus(S.anginosus)is more prevalent in the gastric mucosa of patients with GC than in that of those without GC.S.anginosus infection can spontaneously induce chronic gastritis,mural cell atrophy,mucoid chemotaxis,and heterotrophic hyperplasia,which promote the development of precancerous lesions of GC(PLGC).S.anginosus also disrupts the gastric barrier function,promotes the proliferation of GC cells,and inhibits apoptosis.However,S.anginosus is underrepresented in the literature.Recent reports suggest that it may cause precancerous lesions,indicating its emerging pathogenicity.Modern novel molecular diagnostic techniques,such as polymerase chain reaction,genetic testing,and Ultrasensitive Chromosomal Aneuploidy Detection,can be used to gastric precancerous lesions via microbial markers.Therefore,we present a concise summary of the relationship between S.anginosus and PLGC.Our aim was to further investigate new methods of preventing and treating PLGC by exploring the pathogenicity of S.anginosus on PLGC.

Prospects in the application of ultrasensitive chromosomal aneuploidy detection in precancerous lesions of gastric cancer

Gastric cancer(GC)is a prevalent malignant tumor within the digestive system,with over 40%of new cases and deaths related to GC globally occurring in China.Despite advancements in treatment modalities,such as surgery supplemented by adjuvant radiotherapy or chemotherapeutic agents,the prognosis for GC remains poor.New targeted therapies and immunotherapies are currently under invest-igation,but no significant breakthroughs have been achieved.Studies have indicated that GC is a heterogeneous disease,encompassing multiple subtypes with distinct biological characteristics and roles.Consequently,personalized treatment based on clinical features,pathologic typing,and molecular typing is crucial for the diagnosis and management of precancerous lesions of gastric cancer(PLGC).Current research has categorized GC into four subtypes:Epstein-Barr virus-positive,microsatellite instability,genome stability,and chromosome instability(CIN).Technologies such as multi-omics analysis and gene sequencing are being employed to identify more suitable novel testing methods in these areas.Among these,ultrasensitive chromosomal aneuploidy detection(UCAD)can detect CIN at a genome-wide level in subjects using low-depth whole genome sequencing technology,in conjunction with bioinformatics analysis,to achieve qualitative and quantitative detection of chromosomal stability.This editorial reviews recent research advancements in UCAD technology for the diagnosis and management of PLGC.

Traditional Chinese medicine for transformation of gastric precancerous lesions to gastric cancer:A critical review

Gastric cancer(GC)is a common gastrointestinal tumor.Gastric precancerous lesions(GPL)are the last pathological stage before normal gastric mucosa transforms into GC.However,preventing the transformation from GPL to GC remains a challenge.Traditional Chinese medicine(TCM)has been used to treat gastric disease for millennia.A series of TCM formulas and active compounds have shown therapeutic effects in both GC and GPL.This article reviews recent progress on the herbal drugs and pharmacological mechanisms of TCM in preventing the transformation from GPL to GC,especially focusing on antiinflammatory,anti-angiogenesis,proliferation,and apoptosis.This review may provide a meaningful reference for the prevention of the transformation from GPL to GC using TCM.

Xiaojianzhong decoction prevents gastric precancerous lesions in rats by inhibiting autophagy and glycolysis in gastric mucosal cells

BACKGROUND Gastric precancerous lesions(GPL)precede the development of gastric cancer(GC).They are characterized by gastric mucosal intestinal metaplasia and dysplasia caused by various factors such as inflammation,bacterial infection,and injury.Abnormalities in autophagy and glycolysis affect GPL progression,and their effective regulation can aid in GPL treatment and GC prevention.Xiaojianzhong decoction(XJZ)is a classic compound for the treatment of digestive system diseases in ancient China which can inhibit the progression of GPL.However,its specific mechanism of action is still unclear.AIM To investigate the therapeutic effects of XJZ decoction on a rat GPL model and the mechanisms underlying its effects on autophagy and glycolysis regulation in GPLs.METHODS Wistar rats were randomly divided into six groups of five rats each and all groups except the control group were subjected to GPL model construction for 18 wk.The rats’body weight was monitored every 2 wk starting from the beginning of modeling.Gastric histopathology was examined using hematoxylin-eosin staining and Alcian blue-periodic acid-Schiff staining.Autophagy was observed using transmission electron microscopy.The expressions of autophagy,hypoxia,and glycolysis related proteins in gastric mucosa were detected using immunohistochemistry and immunofluorescence.The expressions of the following proteins in gastric tissues:B cell lymphoma/Leukemia-2 and adenovirus E1B19000 interacting protein 3(Bnip-3),microtubule associated protein 1 light chain 3(LC-3),moesin-like BCL2-interacting protein 1(Beclin-1),phosphatidylinositol 3-kimase(PI3K),protein kinase B(AKT),mammalian target of rapamycin(mTOR),p53,AMP-activated protein kinase(AMPK),and Unc-51 like kinase 1(ULK1)were detected using western blot.The relative expressions of autophagy,hypoxia,and glycolysis related mRNA in gastric tissues was detected using reverse transcription-polymerase chain reaction.RESULTS Treatment with XJZ increased the rats’body weight and improved GPL-related histopathological manifestations.It also decreased autophagosome and autolysosome formation in gastric tissues and reduced Bnip-3,Beclin-1,and LC-3II expressions,resulting in inhibition of autophagy.Moreover,XJZ down-regulated glycolysis-related monocarboxylate transporter(MCT1),MCT4,and CD147 expressions.XJZ prevented the increase of autophagy level by decreasing gastric mucosal hypoxia,activating the PI3K/AKT/mTOR pathway,inhibiting the p53/AMPK pathway activation and ULK1 Ser-317 and Ser-555 phosphorylation.In addition,XJZ improved abnormal gastric mucosal glucose metabolism by ameliorating gastric mucosal hypoxia and inhibiting ULK1 expression.CONCLUSION This study demonstrates that XJZ may inhibit autophagy and glycolysis in GPL gastric mucosal cells by improving gastric mucosal hypoxia and regulating PI3K/AKT/mTOR and p53/AMPK/ULK1 signaling pathways,providing a feasible strategy for the GPL treatment.

Research of Helicobacter pylori infection in precancerous gastric lesions

INTRODUCTION Helicobacter pylori(Hp)infection has beenconsidered to play significant roles in pathogenesisof peptic ulcer.Additionally Hp is associated withthe development of gastric epithelial hyperplasiaand lymphoid malignancies.The InternationalAgency for Research on Cancer has classified lip asa class Ⅰ carcinogen and a definite cause of gastriccancer in humans.Hp infection first causes chronicactive gastritis and may slowly lead to infection ofwhole stomach.In the late stages of infection,mucosal atrophy and intestinal metaplasia(IM),

Expression and significance of Musashi-1 in gastric cancer and precancerous lesions

AIM:To investigate expression of stem cell marker Musashi-1(Msi-1)in relationship to tumorigenesis and progression of intestinal-type gastric cancer(GC).METHODS:Endoscopic biopsy specimens and surgical specimens were obtained,including 54 cases of intestinal-type GC,41 high-grade intraepithelial neoplasia,57low-grade intraepithelial neoplasia,31 intestinal metaplasia,and 36 normal gastric mucosa.Specimens were fixed in 10%paraformaldehyde,conventionally dehydrated,embedded in paraffin,and sliced in 4-μm-thick serial sections.Two-step immunohistochemical staining was used to detect Msi-1 and proliferating cell nuclear antigen(PCNA)expression.Correlation analysis was conducted between Msi-1 and PCNA expression.The relationship between Msi-1 expression and clinicopathological parameters of GC was analyzed statistically.RESULTS:There were significant differences in Msi-1and PCNA expression in different pathological tissues(χ2=15.37,P<0.01;χ2=115.36,P<0.01).Msi-1and PCNA-positive cells were restricted to the isthmus of normal gastric glands.Expression levels of Msi-1and PCNA in intestinal metaplasia were significantly higher than in normal mucosa(U=392.0,P<0.05;U=40.50,P<0.01),whereas there was no significant difference compared to low or high-grade intraepithelial neoplasia.Msi-1 and PCNA expression in intestinaltype GC was higher than in high-grade intraepithelial neoplasia(U=798.0,P<0.05;U=688.0,P<0.01).There was a significantly positive correlation between Msi-1 and PCNA expression(rs=0.20,P<0.01).Msi-1expression in GC tissues was correlated with their lymph node metastasis and tumor node metastasis stage(χ2=12.62,P<0.01;χ2=11.24,P<0.05),but not with depth of invasion and the presence of distant metastasis.CONCLUSION:Msi-1-positive cells may play a key role in the early events of gastric carcinogenesis and may be involved in invasion and metastasis of GC.

Significance and relationship between Cripto-1 and p-STAT3 expression in gastric cancer and precancerous lesions

AIM:To explore the relationship between Cripto-1 (CR-1) and tyrosine phosphorylation STAT3 (p-STAT3) expressions in gastric cancer (GC) and gastric carcinogensis and metastasis.METHODS: The PV9000 immunohistochemical method was used to detect the expression of CR-1 and p-STAT3 in 178 cases of GC, 95 matched normal gastric mucosa, 40 chronic atrophic gastritis (CAG), 48 intestinal meta-plasia (IM) and 25 dysplasia (DYS). RESULTS: The positive rates of CR-1 and p-STAT3 expression were significantly higher in CAG (65.0% and 60.0%), in IM (83.3% and 77.1%), DYS (80.0% and 68%) and GC (71.3% and 60.1%) than in normal gastric mucosa (43.2% and 41.1%, P < 0.05), respectively. The expressions of CR-1 and p-STAT3 (78.3% and 66.7%) were signifi cantly higher in GC with lymphnode metastasis than in those without metastasis (53.1% and 42.9%, P < 0.05). CR-1 expression was also related to histological and Lauren's types of GC (P < 0.001). Furthermore, there was positive relation-ship between CR-1 and p-STAT3 expressions in GC (rk = 0.189, P = 0.002).CONCLUSION: The up-regulation of CR-1 and p-STAT3 may play important roles in gastric carcinogenesis and lymph node metastasis. CR-1 and p-STAT3 expression in GC was positively correlated, and the relevant molecular mechanism requires further investigations.

Anti-Helicobacter pylori therapy followed by celecoxib on progression of gastric precancerous lesions

AIM： To evaluate whether celecoxib, a selective cyclooxygenase 2 （COX-2） inhibitor, could reduce the severity of gastric precancerous lesions following Hel/cobacter pylori （H pylorl） eradication. METHODS： H pylori-eradicated patients with gastric precancerous lesions randomly received either celecoxib （n = 30） or placebo （n = 30） for up to 3 mo. COX-2 expression and activity was determined by immunostaining and prostaglandin E2 （PGE2） assay, cell proliferation by Ki-67 immunostaining, apoptosis by TUNEL staining and angiogenesis by microvascular density （MVD） assay using CD31 staining.RESULTS： COX-2 protein expression was significantly increased in gastric precancerous lesions （atrophy, intestinal metaplasia and dysplasia, respectively） compared with chronic gastritis, and was concomitant with an increase in cell proliferation and angiogenesis. A significant improvement in precancerous lesions was observed in patients who received celecoxib compared with those who received placebo （P 〈 0.001）. Of these three changes, 84.6% of sites with dysplasia regressed in patients treated with celecoxib （P = 0.002） compared with 60% in the placebo group, suggesting that celecoxib was effective on the regression of dysplasia. COX-2 protein expression （P 〈 0.001） and COX-2 activity （P 〈 0.001） in the gastric tissues were consistently lower in celecoxib-treated patients compared with the placebo-treated subjects. Moreover, it was also shown that celecoxib suppressed cell proliferation （P 〈 0.01）, induced cell apoptosis （P 〈 0.01） and inhibited angiogenesis with decreased MVD （P 〈 0.001）. However, all of these effects were not seen in placebo-treated subjects. Furthermore, COX-2 inhibition resulted in the up-regulation of PPARy expression, a protective molecule with anti-neoplastic effects. CONCLUSION： H pylori eradication therapy followed by celecoxib treatment improves gastric precancerous lesions by inhibiting COX-2 activity, inducing apoptosis, and suppressing cell proliferation and angiogenesis.

Loss of heterozygosity on 10q23.3 and mutation of tumor suppressor gene PTEN in gastric cancer and precancerous lesions

AIM: To investigate the loss of heterozygosity (LOH) and mutation of tumor suppressor gene PTEN in gastric cancer and precancerous lesions. METHODS: Thirty cases of normal gastric mucosa, advanced and early stage gastric cancer, intestinal metaplasia, atrophic gastritis, and atypical hyperplasia were analyzed for PTEN LOH and mutations within the entire coding region of PTEN gene by PCR-SSCP denaturing PAGE gel electrophoresis, and PTEN mutation was detected by PCR-SSCP sequencing followed by silver staining. RESULTS: LOH rate found in respectively atrophic gastritis was 10% (3/30), intestinal metaplasia 10% (3/30), atypical hyperplasia 13.3% (4/30), early stage gastric cancer 20% (6/30), and advanced stage gastric cancer 33.3% (9/30), None of the precancerous lesions and early stage gastric cancer showed PTEN mutations, but 10% (3/30) of the advanced stage gastric cancers, which were all positive for LOH, showed PTEN mutation. CONCLUSION: LOH of PTEN gene appears in precancerous lesions, and PTEN mutations are restricted to advanced gastric cancer, LOH and mutation of PTEN gene are closely related to the infiltration and metastasis of gastric cancer.

Effect of transplantation of BMMSCs on pathological change of gastric precancerous lesions of rats

Objective:To build the rat model of gastric precancerous lesions and discuss the effect of transplantation of mesenchymal stem cells(BMMSCs) on the pathological change.Methods:The rat model of gastric precancerous lesions was built using N-methyl-N-nitro-N-nitrosoguanidine.After the intravenous transplantation of BMMSCs,the migration and colonization location was then observed,as well as its effect on the related factors of gastric precancerous lesions,including VEGF,IL-10 and IFN-γ.Results:BMMSCs were mainly colonized in the gastric body and gastric antrum,which could be differentiated into the epithelial and interstitial cells.The expression of VEGF in the transplantation group and non-transplantation group was significantly higher than that in the control group(P<0.05);while the expression of VEGF in the transplantation group was significantly higher than that in the non-transplantation group(t=3.88,P<0.001).The expression of serum IL-10 and IFN- y in the transplantation group and non-transplantation group was significantly higher than that in the control group(P<0.05).while the expression of IL-10 and IFN-γ in the transplantation group was significantly lower than that in the non-transplantation group(t=3.03,P=0.004;t=3.80.P<0.001).Conclusions:BMMSCs can be directionally differentiated into the epithelial and interstitial cells and can also regulate the related growth factors and inflammatory factors to reduce the injury of inflammation,relieve or reverse the process of gastric precancerous lesions.

Gastric precancerous lesions are associated with gene variants in Helicobacter pylori -susceptible ethnic Malays

AIM: To identify genes associated with gastric pre-cancerous lesions in Helicobacter pylori (H. pylori )susceptible ethnic Malays. METHODS: Twenty-three Malay subjects with H. pylori infection and gastric precancerous lesions identified during endoscopy were included as "cases". Thirtyseven Malay subjects who were H. pylori negative and had no precancerous lesions were included as "controls". Venous blood was collected for genotyping with Affymetrix 50K Xba1 kit. Genotypes with call rates < 90% for autosomal single nucleotide polymorphisms (SNPs) were excluded. For each precancerous lesion, associated SNPs were identified from Manhattan plots, and only SNPs with a χ2 P value < 0.05 and Hardy Weinberg Equilibrium P value > 0.5 was considered as significant markers. RESULTS: Of the 23 H. pylori -positive subjects recruited, one sample was excluded from further analysis due to a low genotyping call rate. Of the 22 H. pylori positive samples, atrophic gastritis only was present in 50.0%, complete intestinal metaplasia was present in 18.25%, both incomplete intestinal metaplasia and dysplasia was present in 22.7%, and dysplasia only was present in 9.1%. SNPs rs9315542 (UFM1 gene), rs6878265 (THBS4 gene), rs1042194 (CYP2C19 gene) and rs10505799 (MGST1 gene) were significantly associated with atrophic gastritis, complete intestinal metaplasia, incomplete metaplasia with foci of dysplasia and dysplasia, respectively. Allele frequencies in "cases" vs "controls" for rs9315542, rs6878265, rs1042194 and rs10505799 were 0.4 vs 0.06, 0.6 vs 0.01, 0.6 vs 0.01 and 0.5 vs 0.02, respectively. CONCLUSION: Genetic variants possibly related to gastric precancerous lesions in ethnic Malays susceptible to H. pylori infection were identified for testing in subsequent trials.

Risk Factors of Precancerous Gastric Lesions in A Population at High Risk of Gastric Cancer

Objective： In cancer prevention, the targeting of precancerous lesions has been recognized as the most promising method. However, little attention has been paid to the risk factors of precancerous gastric lesions, especially in rural China where there is high prevalence of precancerous gastric lesions. We therefore conducted a cross-sectional study in Liaoning province, China, to investigate the potential risk and protective factors of these precancerous gastric lesions. Methods： A total of 1,179 subjects with high risk of gastric cancer from Zhuanghe County were included in this study. Standard questionnaires were used in collecting epidemiological factors and the data were then analyzed by the unconditional logistic regression model. Results： Smoking and drinking were the risk factors for the precancerous gastric lesions among rural subjects, and the association of smoking or drinking and the precancerous gastric lesions increased in strength with the daily consumption and duration. As the factors such as age, gender, smoking, alcohol were controlled, a multivariable analysis revealed that there was a significant correlation between the deep-fry food intake and the gastric epithelial dysplasia with the odds ratio （OR） of 1.78 [95% confidence interval （CI）： 1.01-3.12]. Garlic eating was shown to confer protection against the development of gastric ulcer （OR=0.55, 95% CI： 0.33-0.92）. Conclusion： Smoking and drinking were the risk factors for the precancerous gastric lesions among rural subjects. Deep-fry food intake might be one of the risk factors for the precancerous gastric lesions and garlic eating was shown to confer protection against the development of gastric ulcer among rural Chinese population.

Expression of p-STAT3 and vascular endothelial growth factor in MNNG-induced precancerous lesions and gastric tumors in rats

AIM: To investigate the dynamic expression of p-signal transducer and activator of transcription 3 (STAT3) and vascular endothelial growth factor (VEGF) in the formation of gastric tumors induced by drinking water containing N-methyl-N’-nitro-N-nitrosoguanidine (MNNG) in Wistar rats. METHODS: One hundred and twenty Wistar rats were randomly divided into two groups (60 in each group): Control group and Model group. The rats in each group were then randomly divided into three groups (20 in each group): C/M15, C/M25 and C/M40 (15, 25 and 40 represent the number of feeding weeks from termination). Rats in the control group received normal drinking water and rats in the model group received drinking water containing 100 μg/mL MNNG. Stomach tissues were collected at the end of the 15th, 25th and 40th week, respectively, for microscopic measurement using hematoxylin and eosin staining. The expression of p-STAT3 and VEGF in different pathological types of gastric tissue, including normal, inflammation, atrophy, hyperplasia and gastric stromal tumor, was observed by immunohistochemistry and Western blot, and the corelation between p-STAT3 and VEGF was analyzed. RESULTS: (1) The expression of p-STAT3 in tissue with gastritis, atrophy, dysplasia and gastric stromal tumor were significantly increased in the model group compared with the control group (2.5 ± 1.0, 2.75 ± 0.36, 6.2 ± 0.45, 5.67 ± 0.55 vs 0.75 ± 0.36, P = 0.026, 0.035, 0.001, 0.002, respectively); the expression of p-STAT3 in tissue with dysplasia was higher than that in samples with gastritis or atrophy (6.2 ± 0.45 vs 2.5 ± 1.0, P = 0.006; 6.2 ± 0.45 vs 2.75 ± 0.36, P = 0.005, respectively); however, the expression of p-STAT3 in gastritis and atrophy was not significantly different (P > 0.05); (2) the expression of VEGF in tissue with gastritis, atrophy, dysplasia and gastric stromal tumor was significantly increased in the model group compared with normal gastric mucosa; and the expression of VEGF in tissue with dysplasia was higher than that in tissue with inflammation and atrophy (10.8 ± 1.96 vs 7.62 ± 0.25, P = 0.029; 10.8 ± 1.96 vs 6.26 ± 0.76, P = 0.033, respectively); similarly, the expression of VEGF in tissue with gastritis and atrophy was not significantly different (P > 0.05); and (3) the expression of VEGF was positively correlated with p-STAT3. CONCLUSION: p-STAT3 plays an important role in gastric cancer formation by regulating the expression of VEGF to promote the progression of gastric tumor from gastritis.

Treatment of gastric precancerous lesions with Weiansan

AIM： To observe the curative effect of Weiansan （WAS） on gastric precancerous lesions （GPL） and H pylori elimination. METHODS： Seventy-six patients with GPL were randomly divided into two groups： WAS group （n = 42） and Weifuchun （WFC） group （n = 34）. The patients in the WAS group were administered 5 g WAS 3 times a day, and the patients in the WFC group took WFC （4 tablets） 3 times a day. To monitor inflammation of gastric mucosa, degree of glandular atrophy （GA）, intestinal metaplasia （IM） and dysplasia, and H pylori infection, all patients underwent gastroscopy and biopsy with pathological examination before and after treatment. Fifty male Sprague-Dawley （SD） rats were used in animal experiments. Of these, 10 served as the control group （n = 10）, 40 were given ranitidine combined with N-methyl- N^1-nitro-N-nitrosoguanidine （MNNG） for 12 wk and divided into 4 groups randomly： model group （n = 10）, high-dose WAS group （n = 10）, low-close WAS group （n = 10） and WFC group （n = 10）. Twelve weeks later, all rats were killed and a 2 cm ×1 cm tissue was taken from the lesser curvature of the gastric antrum. H pylori infection was determined by the fast urease method. RESULTS： The curative effect in WAS groups was similar to that in WFC groups. There was no statistical difference in degree of GA, IM and dysplasia between WAS and WFC groups. The rate of Hpylori infection in the model group （positive/negative： 9/1） was significantly higher than that in the control group （positive/negative： 1/9） （P 〈 0.01）. H pylori elimination in the high-dose WAS group （positive/negative： 4/6） and low-dose WAS group （positive/negative： 6/4） was similar to that in the WFC group （positive/negative： 4/6） （P 〉 0.05）.CONCLUSION： WAS improves clinical symptoms by suppressing GA, IM and dysplasia and eliminating H pylori.

Experimental study on model establishment, mechanism of production, and reverse therapy of gastric mucosal precancerous lesions in rats

This study was designed to establish an animal model of gastric mucosal precancerous lesions in Wistar rats and on this model, the mechanism to produce the precancerous lesions and their reverse therapy were studied. Ranitidine (R) 0.03% in the diet, N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)50 μg/ml in drinking water, or both of them were administered to Wistar rats for 20 weeks. The iats were maintained without the drugs for additional 23 weeks. A control group of rats without any treatment of drugs were kept for 43 weeks Intestinal metaplasia (IM) was found in 86.5% of the rats in MNNG group, 22.5% in R groupand 100% in MNNG+R while only 7.5% in the control. The incidence of IM was significantly different between MNNG+R group and R group or MNNG group. The number of metaplastic glands was also the highest in the MNNG+R group. The therapeutic effects of retinoic acid (RA) and sodium butyrate (SB) on the iNduced precancerousous lesions of the glandular gastric mucosa were observed. It was found that the incidence of IM, moderate and severe dysplasia, and gastric cancer and the number of metaplastic glands in the pylorus and fundus were significantly lower in RA treated group (72.0%, 24.0%, 0%, 130.2±93.9 and 51.5±39.1) and SB treated gioup (60.0%,20.0%, 0%, 70.3±46.8, and 39.8±29.6) than in the RA untreated group (100%, 52.2%, 16.0%, 442.4±230.0 and 247.4±112.07) and the SB untreated group (88.0%, 48.0%. 16.0%, 241.4±113.9 and 146.4±66.3)(P<0.01 to 0.05). A mucosal flap with vascular pedicle from the gastric wall of the Wistar rats was transplanted to the duodenum, jejunum and colon respectively and the rats were killed in the 3td, 6th, 9th and 12th month after operation. IM was found in all the gastric grafts to the intestines with optical and electron microscopy. It is concluded on the basis of the findings that the concomitant administration of MNNG and R is a reliable method to induce IM of gastric mucosa in rats; RA and SB are efficient agents for the reverse thevapy of the precancerous lesions of gastric glandular mucosa in rats; and the formation of IM of gastric mucosa might be a pH-related process. The possible mechanism of the development of IM was discussed.

Abnormal Change of p53 Gene in Gastric and PrecancerousLesions and APC Gene Deletion in Gastric Carcinoma and Near Tissues

p53 gene mutation (exon4, 5, 6, 7, 8 and intron6) in gastric cancer and precancerous lesions and p53 gene (exon4 and ontron6), APC gene deletion in gastric carcinomas were studied by PCR/SSCP and PCR/RFLP- Results showed mutation rate of p53 in metaplasia, dysplasia and gastric carcinoma was 37. 5 % (3/8), 42. 11 % (8/19), 53. 33 (16/30) respectively- There was significant dif-ference among groups of metaplasia, dysplasia, cancer and normal controls. Noexon8 mutation was found in metaplasia and dysplasia, but 4 cases were found to have exon8 mutation in cancer group. It is suggested that exon8 mutation occurs at the late stage of gastric cancer, but exon 5, 6, 7 mutation occur in the course ofprecancerous lesion to cancer. Loss of heterozygosity (LOH) of exon4, intron6,APC was 47,37 % (9/19), 8. 73% (2/23), 16. 67 % (3/18) respectively. LOH of exon4 had something to do with poor differentiation, lymph node metastasis,depth of invasion- LOH of exon4 may be one of prognostic marker of gastric cancer. We are led to conclude that p53 gene mutation is an early event and perhaps work together with ras oncogene in gastric carcinogenesis

Expression of ornithine decarboxylase in precancerous and cancerous gastric lesions

AIM: To investigate the expression of ornithine decarboxylase (ODC) in precancerous and cancerous gastric lesions. METHODS: We studied the expression of ODC in gastric mucosa from patients with chronic superficial gastritis (CSG,n = 32),chronic atrophic gastritis CAG,n = 43; 15 with and 28 without intestinal metaplasia (IM),gastric dysplasia (DYS,n = 11) and gastric cancer (GC,n = 48) tissues using immunohistochemical staining. All 134 biopsy specimens of gastric mucosa were collected by gastroscopy. METHODS: The positive rate of ODC expression was 34.4%,42.9%,73.3%,81.8% and 91.7% in cases with CSG,CAG without IM,CAG with IM,DYS and GC,respectively (P < 0.01),The positive rate of ODC expression increased in the order of CSG < CAG (without IM) < CAG (with IM) < DYS and finally,GC. In addition,ODC positive immunostaining rate was lower in well-differentiated GC than in poorly-differentiated GC (P < 0.05). CONCLUSION: The expression of ODC is positively correlated with the degree of malignity of gastric mucosa and development of gastric lesions. This finding indicates that ODC may be used as a good biomarker in the screening and diagnosis of precancerous lesions.

An experimental research of Weining granule in treating gastric precancerous lesions

Objective： To investigate potential therapeutic effects and mechanism of Weining granule in the treatment of gastric precancerous lesions. Methods： Sixty rats were randomly assigned to a blank group or a model group or to receive retinoic acid or high-, medium- or low- dose of Weining granule. General conditions of the animals were observed before and after treatment. Changes in gastric mucosal pathohistology, telomerase activity, proliferation index （PI） and apoptosis index （AI） were measured. Results： General conditions, including activity and eating, were improved in all Weining-granule-treated groups with the numbers of rats having intestinal metaplasia （IM）, atypical hyperplasia （ATP） or positive telomerase activity being significantly lower than those in the model group （P 〈 0.05 or P 〈 0.01）. Compared with the model group, all doses of Weining granule significantly decreased PI （P 〈 0.01） and increased AI （P 〈 0.05）. Conclusion： Weining granule may provide a therapeutic benefit for the treatment of gastric precancerous lesions by inhibiting telomerase activity and proliferation of gastric cancer cells and by accelerating their apoptosis.

Gastric mucosal precancerous lesions in Helicobacter pyloriinfected pediatric patients in central China:A single-center,retrospective investigation

BACKGROUND Helicobacter pylori(H.pylori)infects about 50%of the world population and is the major cause of chronic gastritis,peptic ulcers,and gastric cancer.Chronic H.pylori infection induces gastric mucosal precancerous lesions mostly in adulthood,and it is debatable whether these pathological conditions can occur in childhood and adolescents as well.Since this is a critical issue to determine if intervention should be offered for this population group,we investigated the gastric mucosal precancerous lesions in pediatric patients in an area in central China with a high prevalence of H.pylori and gastric cancer.AIM To investigate the relationship of H.pylori infection and gastric mucosal precancerous lesions in children and adolescents in central China.METHODS We screened 4258 ward-admitted children and adolescent patients with upper gastrointestinal symptoms,and finally enrolled 1015 pediatric patients with H.pylori infection and endoscopic and histological data.H.pylori infection status was determined by rapid urease test and histopathological examination.Both clinical and pathological data were collected and analyzed retrospectively.Occurrence of gastric mucosal precancerous lesions,inflammatory activity and degree of inflammatory cell infiltration between H.pylori-positive and-negative groups were compared.RESULTS Among the 1015 eligible children and adolescents,the overall H.pylori infection rate was 84.14%(854/1015).The infection rate increased with age.The incidence of gastric mucosal precancerous lesions in H.pylori-infected children was 4.33%(37/854),which included atrophic gastritis(17 cases),intestinal metaplasia(11 cases)and dysplasia(9 cases).In H.pylori-negative patients,only 1 atrophic gastritis case[0.62%,(1/161)]was found(P<0.05).Active inflammation in H.pyloriinfected patients was significantly higher than that in non-infected patients,and the H.pyloriinfected group showed more severe lymphocyte and neutrophil granulocyte infiltration(P<0.001).In addition,endoscopy revealed that the most common findings in H.pylori-positive patients were antral nodularity,but in H.pylori-negative patients only superficial gastritis was observed.CONCLUSION In children and adolescents,gastric mucosal precancerous lesions occurred in 4.33%of H.pyloriinfected patients in central China.These cases included atrophic gastritis,intestinal metaplasia,and dysplasia.The data revealed an obvious critical issue requiring future investigation and intervention for this population group.

Effect of Helicobacterpyloriinfection on Bax protein expression in patients with gastric precancerous lesions

AIM： To investigate the effect of Helicobacter pylori （H pylon） infection on Bax protein expression, and explore the role of Hpyloriin gastric carcinogenesis. METHODS： Hpyloriwas assessed by rapid urease test and Warthin-Starry method, and expression of Bax protein was examined immunohistochemically in 72 patients with pre-malignant lesions. RESULTS： Bax protein was differently expressed in intestinal metaplasia and gastric dysplasia, and showed 63.99% positivity. The positivity of Bax protein expression in Hpylori-positive gastric precancerous lesions （72.3%） was significantly higher than that in H pylori-negative gastric precancerous lesions （48.0%, x^2= 4.191, P〈0.05）. Hpyloriinfection was well correlated with the expression of Bax protein in gastric precancerous lesions （r= 0.978, P〈0.01）. After eradication of H pylori, the positivity of Bax protein expression significantly decreased in Hpylori-positive gastric precancerous lesions （x^2 = 5.506, P〈0.05）. In the persisting H pylori-infected patients, the positivity of Bax protein expression was not changed. CONCLUSION： H pyloriinfection may be involved in the upregulation of Bax gene, which might be one of the mechanisms of Hpyloriinfection-induced gastric epithelial cell apoptosis. Hpylorimight act as a tumor promoter in the genesis of gastric carcinoma and eradication of Hpylori could inhibit gastric carcinogenesis.