Effect of cetuximab plus FOLFOX4 regimen on clinical outcomes in advanced gastric carcinoma patients receiving evidence-based care

BACKGROUND Although chemotherapy is effective for treating advanced gastric carcinoma(aGC),it may lead to an adverse prognosis.Establishing a highly effective and low-toxicity chemotherapy regimen is necessary for improving efficacy and outcomes in aGC patients.AIM To determine the efficacy and safety of cetuximab(CET)combined with the FOLFOX4 regimen(infusional fluorouracil,folinic acid,and oxaliplatin)as firstline therapy for patients with aGC,who received evidence-based care(EBC).METHODS A total of 117 aGC patients who received EBC from March 2019 to March 2022 were enrolled.Of these,60 in the research group(RG)received CET+FOLFOX4 as first-line therapy,whereas 57 in the control group(CG)received FOLFOX4.The efficacy[clinical response rate(RR)and disease control rate(DCR)],safety(liver and kidney dysfunction,leukopenia,thrombocytopenia,rash,and diarrhea),serum tumor marker expression[STMs;carbohydrate antigen(CA)19-9,CA72-4,and carcinoembryonic antigen(CEA)],inflammatory indicators[interleukin(IL)-2 and IL-10],and quality of life(QOL)of the two groups were compared.RESULTS A markedly higher RR and DCR were observed in the RG compared with the CG,with an equivalent safety profile between the two groups.RG exhibited notably reduced CA19-9,CA72-4,CEA,and IL-2 levels following treatment,which were lower than the pre-treatment levels and those in the CG.Post-treatment IL-10 was statistically increased in RG,higher than the pre-treatment level and the CG.Moreover,a significantly improved QOL was evident in the RG.CONCLUSION The CET+FOLFOX4 regimen is highly effective as first-line treatment for aGC patients receiving EBC.It facilitates the suppression of STMs,ameliorates the serum inflammatory microenvironment,and enhances QOL,without increased adverse drug effects.

Impact of liver metastasis on immunotherapy in gastric carcinoma

The editorial discusses the impact of liver metastasis on immunotherapy efficacy in gastric cancer(GC)patients.Liver metastasis can hinder the effectiveness of immunotherapy by altering the immune microenvironment,leading to systemic loss of T-cells and reduced treatment response.Studies suggest that liver meta-stases serve as a negative baseline factor for immunotherapy efficacy,resulting in poorer progression-free survival and objective response rates.Strategies such as liver-mediated radiotherapy may help improve treatment outcomes by reshaping the liver’s immune microenvironment and reducing T-cell depletion.Understand-ing the complex interplay between liver metastasis and immunotherapy response is crucial for optimising patient care in GC.

MiR-204-3p overexpression inhibits gastric carcinoma cell proliferation by inhibiting the MAPK pathway and RIP1/MLK1 necroptosis pathway to promote apoptosis

BACKGROUND Gastric carcinoma(GC)is the third most frequent cause of cancer-related death,highlighting the pressing need for novel clinical treatment options.In this regard,microRNAs(miRNAs)have emerged as a promising therapeutic strategy.Studies have shown that miRNAs can regulate related signaling pathways,acting as tumor suppressors or tumor promoters.AIM To explore the effect of miR-204-3p on GC cells.METHODS We measured the expression levels of miR-204-3p in GC cells using quantitative real-time polymerase chain reaction,followed by the delivery of miR-204-3p overexpression and miR-204-3p knockdown vectors into GC cells.CCK-8 was used to detect the effect of miR-204-3p on the proliferation of GC cells,and the colony formation ability of GC cells was detected by the clonal formation assay.The effects of miR-204-3p on GC cell cycle and apoptosis were detected by flow cytometry.The BABL/c nude mouse subcutaneous tumor model using MKN-45 cells was constructed to verify the effect of miR-204-3p on the tumorigenicity of GC cells.Furthermore,the study investigated the effects of miR-204-3p on various proteins related to the MAPK signaling pathway,necroptosis signaling pathway and apoptosis signaling pathway on GC cells using Western blot techniques.RESULTS Firstly,we found that the expression of miR-204-3p in GC was low.When treated with the lentivirus overexpression vector,miR-204-3p expression significantly increased,but the lentivirus knockout vector had no significant effect on miR-204-3p.In vitro experiments confirmed that miR-204-3p overexpression inhibited GC cell viability,promoted cell apoptosis,blocked the cell cycle,and inhibited colony formation ability.In vivo animal experiments confirmed that miR-204-3p overexpression inhibited subcutaneous tumorigenesis ability in BABL/c nude mice.Simultaneously,our results verified that miR-204-3p overexpression can inhibit GC cell proliferation by inhibiting protein expression levels of KRAS and p-ERK1/2 in the MAPK pathway,as well as inhibiting protein expression levels of p-RIP1 and p-MLK1 in the necroptosis pathway to promote the BCL-2/BAX/Caspase-3 apoptosis pathway.CONCLUSION MiR-204-3p overexpression inhibited GC cell proliferation by inhibiting the MAPK pathway and necroptosis pathway to promote apoptosis of GC cells.Thus,miR-204-3p may represent a new potential therapeutic target for GC.

Deltonin enhances gastric carcinoma cell apoptosis and chemosensitivity to cisplatin via inhibiting PI3K/AKT/mTOR and MAPK signaling

BACKGROUND As an active ingredient derived from Dioscorea zingiberensis C.H.Wright,deltonin has been reported to show anti-cancer effects in a variety of malignancies.AIM To investigate the role and mechanism of action of deltonin in promoting gastric carcinoma(GC)cell apoptosis and chemosensitivity to cisplatin.METHODS The GC cell lines AGS,HGC-27,and MKN-45 were treated with deltonin and then subjected to flow cytometry and 3-(4,5-dimethylthiazol-2-yl)-3,5-diphenyltet-razolium bromide assays for cell apoptosis and viability determination.Western blot analysis was conducted to examine alterations in the expression of apoptosis-related proteins(Bax,Bid,Bad,and Fas),DNA repair-associated proteins(Rad51 and MDM2),and phosphatidylinositol 3-kinase/protein kinase B/mammalian target of the rapamycin(PI3K/AKT/mTOR)and p38-mitogen-activated protein kinase(MAPK)axis proteins.Additionally,the influence of deltonin on GC cell chemosensitivity to cisplatin was evaluated both in vitro and in vivo.RESULTS Deltonin treatment weakened viability,enhanced apoptosis,and dampened DNA repair in GC cell lines in a dose-dependent pattern.Furthermore,deltonin mitigated PI3K,AKT,mTOR,and p38-MAPK phosphorylation.HS-173,an inhibitor of PI3K,attenuated GC cell viability and abolished deltonin inhibition of GC cell viability and PI3K/AKT/mTOR and p38-MAPK pathway activation.Deltonin also promoted the chemosensitivity of GC cells to cisplatin via repressing GC cell proliferation and growth and accelerating apoptosis.CONCLUSION Deltonin can boost the chemosensitivity of GC cells to cisplatin via inactivating p38-MAPK and PI3K/AKT/mTOR signaling.

Update on diagnosis and treatment of early signet-ring cell gastric carcinoma: A literature review

Gastric signet-ring cell gastric carcinoma(GSRC)is an unfavorable subtype of gastric cancer(GC)that presents with greater invasiveness and poorer prognosis in advanced stage than other types of GC.However,GSRC in early stage is often considered an indicator of less lymph node metastasis and more satisfying clinical outcome compared to poorly differentiated GC.Therefore,the detection and diagnosis of GSRC at early stage undoubtedly play a crucial role in the management of GSRC patients.In recent years,technological advancement in endoscopy including narrow-band imaging and magnifying endoscopy has significantly improved the accuracy and sensitivity of the diagnosis under endoscopy for GSRC patients.Researches have confirmed that early stage GSRC that meets the expanded criteria of endoscopic resection showed comparable outcomes to surgery after receiving endoscopic submucosal dissection(ESD),indicating that ESD could be considered standard treatment for GSRC after thorough selection and evaluation.This article summarizes the current knowledge and updates pertaining to the endoscopic diagnosis and treatment of early stage signet-ring cell gastric carcinoma.

Expression of COX-2 in Different Subtypes of Gastric Intestinal Metaplasia and Gastric Carcinoma by Tissue Microarray

Objective: To study the expression of cyclooxygenase-2 (COX-2) protein in different subtypes of intestinal metaplasia (IM) and gastric carcinoma, evaluate the possibility of COX-2 forecasting the risk of malignant potential of IM, and the relationship between COX-2 expression and gastric carcinogenesis. Methods: Forty cases of chronic atrophic gastritis (CAG) with IM, 40 cases of gastric carcinoma and corresponding paracancerous tissues were selected to construct a tissue microarray. High iron diamine/alcian blue (HID/AB) staining and Hematoxylin and Eosin (HE) staining was used to classify IM and gastric carcinoma, and the expression of COX-2 protein detected in different subtypes of IM and gastric cancer by using immunohistochemistry. Results: The positive expression rate of COX-2 was 45.65%, 59.38% and 77.27% in IM foci in CAG, IM foci in paracancerous tissues, and intestinal-type gastric carcinoma, respectively, significantly higher than in diffuse-type gastric cancer (16.67%)(P<0.05, 0.005 and 0.005, respectively), and the expression intensity of COX-2 protein showed a increased tendency gradually in the sequence of IM foci in CAG→IM foci in paracancerous tissues→intestinal-type gastric carcinoma (P<0.005). The positive expression rate of COX-2 protein in type Ⅲ IM was significantly higher than in type Ⅰ and type Ⅱ IM (P<0.005 and 0.05, respectively), and the expression intensity also showed a increased tendency gradually from type Ⅰ to type Ⅲ IM (P<0.005). Conclusion: The expression level of COX-2 was increased gradually along with the increase of the risk of malignancy of IM, and its expression level may be a useful index to forecast the risk of malignant potential of IM. COX-2 expression was associated with intestinal-type gastric carcinoma, but it might also have some role in the carcinogenesis of diffuse-type gastric carcinoma.

Vascular Endothelial Growth Factor C Expression in Gastric Carcinoma and Its Relationship with Lymph Node Metastasis

Objective: To study the expression of vascular endothelial growth factor C (VEGF-C) in gastric carcinoma and its relationship with lymph node metastasis. Methods: The expression of VEGF-C mRNA in 5 gastric carcinoma cell lines was detected by reverse transcription-polymerase chain reaction (RT-PCR). Simultaneously, the expression of VEGF-C protein in gastric carcinoma tissues, which were obtained from 63 patients who underwent radical gastrectomy, was detected by immunohistochemistry. Results: Three of the 5 gastric carcinoma cell lines, MKN-45, SGC-7901 and AGS, expressed VEGF-C mRNA. VEGF-C protein was expressed in 52.4% (33/63) of patients. VEGF-C protein expression was more frequently found in tumors with lymph node metastasis than in those without (P<0.01). VEGF-C protein expression was also closely related to lymphatic invasion (P<0.01) and TNM stage (P<0.01). However, there was no significant correlation between VEGF-C expression and the age, gender, tumor size, tumor location, Lauren classification, depth of invasion, and vascular invasion. Conclusion: The expression of VEGF-C is closely related to lymph node metastasis of gastric carcinoma, and lymphangiogenesis might be a new target for treatment of gastric carcinoma.

The Relationship between the Expression of p27^(Kip1),p53 and the Infiltration,Metastasis and Prognosis in Gastric Carcinoma

Objective: To study the relationship between the expression of p27Kip1 and p53, and the infiltration, metastasis and prognosis in gastric carcinoma. Methods: The expression of p27Kip1 and p53 at protein level was determined by immunohistochemical assay (two-step method) in 100 cases of gastric carcinoma. Results: Of the 100 cases, the positive rate of p27Kip1 and p53 expressions were 44% and 49%, respectively. In the group of gastric carcinomas with deep infiltration (infiltration group), lymph nodes metastasis group (metastasis group) and death-within-5-years group (death group), the expression of p27Kip1 was statistically lower (_P<0.05). In the metastasis group and death group, the expression of p53 was significantly higher (P<0.05). The results of the monovariate analysis revealed that the 5-year survival rate of the high p27Kip1 expression group was 70.59%, which is higher than those of the low p27Kip1 expression group (54.55%) and the negative experession group (26%). The 5-year survival rate of the high p53 expression group was 19.23%, which was lower than those of the p53 low expression group (43.75%) and the negative group (53.19%). Cox multivariate analysis showed that p27Kip1, like p53, was an independent prognostic index. But p27Klpl protein expression was a stronger independent survival predictor (RR=3.06) than p53 expression (RR=2.33). Conclusion: The low expression of p27Kip1 and the high expression of p53 reflected the more frequent invasion and metastasis, which resulted in the reduced survival of patients. As an independent markers of the gastric carcinoma, the expression of p27Kip1 is more useful than that of p53 in the prognosis prediction of gastric carcinoma.

Role of the tumor microenvironment in the pathogenesis of gastric carcinoma

Gastric carcinoma (GC) is the 4th most prevalent cancer and has the 2nd highest cancer-related mortality rate worldwide. Despite the incidence of GC has decreased over the past few decades, it is still a serious health problem. Chronic inflammatory status of the stomach, caused by the infection of Helicobacter pylori (H. pylori) and through the production of inflammatory mediators within the parenchyma is suspected to play an important role in the initiation and progression of GC. In this review, the correlation between chronic inflammation and H. pylori infection as an important factor for the development of GC will be discussed. Major components, including tumor-associated macrophages, lymphocytes, cancer-associated fibroblasts, angiogenic factors, cytokines, and chemokines of GC microenvironment and their mechanism of action on signaling pathways will also be discussed. Increasing our understanding of how the components of the tumor microenviroment interact with GC cells and the signaling pathways involved could help identify new therapeutic and chemopreventive targets.

Downregulation of survivin by RNAi inhibits growth of human gastric carcinoma cells

AIM: To investigate the inhibitory effect of a specific small survivin interfering RNA (siRNA) on cell proliferation and the expression of survivin in human gastric carcinoma cell line SGC-7901. METHODS: To knockdown survivin expression, a small interfering RNA targeting against survivin was synthesized and transfected into SGC-7901 cells with lipofectamineTM2000. The downregulation of survivin expression at both mRNA and protein levels were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. Cell proliferation inhibition rates were determined by methyl thiazolyl tetrazolium (MTT) assay. The effect of survivin siRNA on cell cycle distribution and cell apoptosis was determined by flow cytometry (FCM). RESULTS: RNA interference could efficiently suppress the survivin expression in SGC-7901 cells. At 48 h after transfection, the expression inhibition rate was 44.52% at mRNA level detected by RT-PCR and 40.17% at protein level by Western blot analysis. Downregulation of survivin resulted in significant inhibition of tumor cell growth in vitro. The cell proliferation inhibition rates at 24, 48 and 72 h after survivin siRNA and non-siliencing siRNA transfection, were 34.06%, 47.61% and 40.36%, respectively. The apoptosis rate was 3.56% and the number of cells was increased in G0/G1 phase from 38.2% to 88.6%, and decreased in S and G2/M phase at 48 h after transfection. CONCLUSION: Downregulation of survivin results in significant inhibition of tumor growth in vitro. The inhibition of survivin expression can induce apoptosis of SGC-7901 cells. The use of survivin siRNA deserves further investigation as a novel approach to cancer therapy.

Caveolin-1,E-cadherin and β-catenin in Gastric Carcinoma,Precancerous Tissues and Chronic Non-atrophic Gastritis

Objective： To investigate the expressions of caveolin-1, E-cadherin and β-catenin in gastric carcinoma, precancerous gastric and chronic non-atrophic gastritis tissues, and evaluate the correlation of these expressions with the development of gastric cancer. Methods： The expressions of caveolin-1, E-cadherin and β-catenin were detected by biotin-streptavidinperoxidase （SP） immunohistochemistry on 58 gastric cancer tissues, 40 precancerous gastric tissues and 42 chronic non-atrophic gastritis tissues. The correlation between the expressions of caveolin-1, E-cadherin and β-catenin, and the clinicopathologic parameters of gastric cancer was analyzed retrospectively. Results： The positive rates of caveolin-1 and E-cadherin expressions in gastric carcinoma were significantly lower than precancerous gastric and chronic non-atrophic gastritis tissues （P〈0.01）. An abnormal rate of β-catenin expression in gastric carcinoma was higher than precancerous gastric and chronic non-atrophic gastritis tissues （P〈0.01）. Moreover, low expressions of caveolin-1, E-cadherin and β-catenin correlated with tumor size, depth of invasion, lymph node metastasis and TNM stage （P〈0.05）. The positive rates of caveolin-1 and E-cadherin expressions decreased （P〈0.01）, while an abnormal rate of β-catenin expression increased inversely, with the degree of atypical hyperplasia （P〈0.01）. Caveolin-1 expression correlated positively with E-cadherin （r=0.41, P〈0.05）. Caveolin-1 （r=-0.36, P〈0.05） and E-cadherin （r=-0.45, P〈0.05） expressions negatively correlated with abnormal β-catenin expression. Conclusion： These results suggested that dysregulated expressions of caveolin-1, E-cadherin and β-catenin correlated with the development of gastric cancer and its biological behavior.

Detection of let-7a microRNA by real-time PCR in gastric carcinoma

AIM: To establish an accurate and rapid stem-loop reverse transcriptional real-time PCR (RT-PCR) method to quantify human let-7a miRNA in gastric cancer. METHODS: According to the sequence of let-7a miRNA,the stem-loop reverse transcriptional primer,the primers and quantitative MGB probes of real-time PCR were designed and synthesized. The dynamic range and the sensitivity of quantitative reverse transcriptional real-time PCR were determined. The levels of let-7a miRNA were examined in 32 gastric carcinoma samples by stem-loop RT-PCR method. RESULTS: The dynamic range and sensitivity of the let-7a miRNA quantification scheme were evaluated,the result showed the assay could precisely detect 10 copies of mature let-7a miRNA in as few as 0.05 ng of total RNA of gastric mucosa. The results of specificity analysis showed no fluorescence signal occurred even though 50 ng of human genomic DNA was added to the reverse transcription (RT) reaction. The expression level of let-7a miRNA in gastric tumor tissues was significantly lower compared to normal tissues in 14 samples from 32 patients. CONCLUSION: The stem-loop RT-PCR is a reliable method to detect let-7a miRNA which may play an important role in the development of gastric carcinoma.

Clinicopathologic characteristics of gastric carcinoma in elderly patients: A comparison with young patients

AIM:To examine the clinicopathologic features of elderly patients with gastric carcinoma and to investigate the relationship between prognosis and age.METHODS: We reviewed the hospital records of 2 014patients with gastric carcinoma retrospectively to compare the clinicopathologic findings in elderly (age ＞70 years) and young (age ＜36 years) patients during the period from 1986 to 2000 in a tertiary referral center in Gwangju, Korea. Overall survival was the main outcome measure.RESULTS: Of the 2 014 patients, 194 (9.6%) were in the elderly group and 137 (6.8%) were in the young group.The elderly and young patients had similar distributions with respect to depth of invasion, nodal involvement, hepatic metastasis, peritoneal dissemination, tumor stage at the initial diagnosis, and type of surgery. Synchronous multiple carcinomas were found in 14/194 (7.2%) of the elderly group and 4/137 (2.9%) of the young group (P＜0.05). Using the Borrmann classification, type Ⅳ was more frequent in the young patients than in the elderly patients (P＜0.05).Significantly more elderly patients had a well or moderately differentiated histology, and more young patients had a poorly differentiated histology and signet ring cell carcinoma (P＜0.001). The 5-year survival rates of elderly and young patients did not differ statistically (52.8% vs 46.5%,P = 0.5290). Multivariate analysis showed that the histologic type, nodal involvement and operative curability were significant prognostic factors, and age itself was not an independent prognostic factor of survival for elderly gastric carcinoma patients.CONCLUSION: Elderly patients with gastric carcinoma do not have a worse prognosis than young patients. The important prognostic factor is whether the patients undergo a curative resection.

Lymph node micrometastasis and its correlation with MMP-2 expression in gastric carcinoma

AIM： To examine matrix metalloproteinase-2 （MMP-2） expression in gastric cancer tissues and to evaluate its relationship with lymph node micrometastasis. MATERIALS： The authors studied 850 lymph nodes resected from 30 patients with gastric carcinoma who underwent gastrectomy with lymphadenetomy using reverse transcription polymerase chain reaction （RT-PCR） assay in addition to H-E staining. MMP-2 expression of the tumor tissues was detected by immunohistochemical technique （EliVision^TM plus）. RESULTS： MMP-2 expression was positive in 21 （70%） cases and negative in g （30%） cases. No significant correlations were found between MMP-2 expression and other variables such as age, gender, tumor location, tumor diameter, Lauren classification and lymphatic invasion. In contrast, MMP-2 expression correlated significantly with depth of tumor infiltration （P = 0.022）, lymph node metastasis （P = 0.030） and tumor differentiation （P = 0.043）. Lymph node micrometastases were detected in 77 （12.5%） lymph nodes of 14 （46.7%） gastric carcinoma patients. MMP-2 expression was positive in 12 （85.7%） of the 14 patients with lymph node micrometastasis, and in g （56.3%） of the 16 patients without lymph node micrometastasis （P = 0.118）. CONCLUSIONS： Our results demonstrate that MMP-2 expression has significant correlation with tumor invasion, tumor differentiation and lymph node metastases. MMP-2 expression may be an important biological characteristics and significant prognostic parameter of gastric carcinoma. We also conclude that MMP-2 may participate in the development of lymph node micrometastasis of gastric carcinoma. Further investigations are needed to draw a conclusion.

Effect and mechanism of the Twist gene on invasion and metastasis of gastric carcinoma cells

AIM: To study the effect of the transfected Twist gene on invasion and metastasis of gastric carcinoma cells and the possible mechanisms involved. METHODS: Human gastric carcinoma MKN28 cells were stably transfected with Twist sense plasmid, and MKN45 cells were stably transfected with Twist antisense plasmid using the lipofectamine transfection technique. RT-PCR, Western blotting, EMSA, gelatin zymography assay, and in vitro invasion and migration assays were performed. Nude mice metastasis models were established by the abdominal cavity transfer method. RESULTS: Cell models (TwistS-MKN28) that steadily expressed high Twist protein were obtained. Compared with MKN28 and pcDNA3-MKN28 cells, adherence, migration and invasion ability of TwistS -MKN28 cells were clearly raised. The number of cancer nodules was increased significantly in the abdominal cavity and liver of nude mice inoculated with TwistS-MKN28 cells. Overexpression of Twist in MKN28 cells increased Tcf-4/ Lef DNA binding activity, and promoted expression of Tcf-4’s downstream target genes cyclin D1 and MMP-2. However, suppression of Twist (TwistAS-MKN45) inhibited MKN45 cell invasion and the expression of cyclin D1 was reduced. The activity of MMP-2 was also decreased. CONCLUSION: These results indicate that Twist promotes gastric cancer cell migration, invasion and metastasis, and Twist may play an important role in Wnt/ Tcf-4 signaling.

Clinicopathologic significance of HER-2/neu protein expression and gene amplification in gastric carcinoma

AIM:To study the HER-2/neu protein expression and gene amplification in gastric carcinoma and their relation.METHODS:One hundred and forty-five formalin-fixed and paraffin-embedded tumor tissue samples from Chinese gastric carcinoma patients were studied with immunohistochemistry(IHC)and fluorescence in situ hybridization(FISH)methods.Clinicopathologic data about all patients were collected.RESULTS:The levels of HER-2 3+,HER-2 2+and HER21+were measurable in 6.9%,8.3%and 17.2%of the samples,respectively.No HER-2 was stained in 67.6% of the samples.FISH showed that HER-2 gene was amplified in 18 samples,10 HER-2 3+samples,5 HER-2 2+samples,and 3 HER-2 1+samples with IHC staining.HER-2 status was not correlated with the sex and age of patients,and tumor size,location or differentiation,but with the depth of invasion,TNM stage,lymph node and distant metastasis as well as histopathological classification of gastric cancer(P<0.05).CONCLUSION:All samples with IHC as HER-2 expression should be analyzed with FISH.Detection of HER-2 gene amplification can assess the malignant biological behaviors and prognosis of gastric cancer.

Cell cycle arrest and apoptotic cell death in cultured human gastric carcinoma cells mediated by arsenic trioxide

AIM: To investigate the effect of arsenic trioxide on human gastric cancer cell line MKN45 with respect to both cytotoxicity and induction of apoptosis in vitro. METHODS: MKN45 cells were treated with arsenic trioxide (As2O3) at the concentration of 1, 5, and 10 μmol/L, respectively, for three successive days. Cell growth and proliferation were observed by cell counting and trypan blue exclusion. Cytotoxicity of As2O3 was determined by MTT assay. Morphologic changes were studied with light microscopy. Flow cytometry was used to assay cell DNA distribution and apoptotic cells were confirmed with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and DNA electrophoresis. RESULTS: The growth of MKN45 cells was significantly inhibited by As2O3 which was confirmed by colony-forming assay. After 7 d of culture with various concentrations of As2O3, colony-forming capacity of MKN45 cells decreased with As2O3 increment in comparison with that of control group. The inhibitory rate of colony-formation was 38.5%, 99.1%, and 99.5% when the concentration of As2O3 was 1, 5, and 10 μmol/L in culture medium, respectively. The cell number of a single colony in drug treatment groups was less than that of control group. The cell-killing rate of As2O3 to MKN45 cells was both dose- and time-dependent with an IC50 of (11.05±0.25) μmol/L After incubation in 10 μmol/L As2O3 for 24 h, the cell-killing rate was 27.1%, and it was close to 50% after 48 h. The results showed that As2O3 induced time- and dose-dependent apoptosis in MKN45 cells, blocked at G2/M phase. The apoptotic peak (sub-G1 phase) appeared and cell apoptotic rate in MKN45 cells was 18.3-32.5% after treatment by 10 umol/L As2O3 for 48 h. The percentage of G2/M cell of the experimental groups was 2.0-5.0 times than that of the control group. Gel electrophoresis of DNA from cells treated with each concentration of As2O3 for 48 h revealed a 'ladder' pattern, indicating preferential DNA degradation at the internucleosomal, linker DNA sections. TUNEL also demonstrated strand breaks in DNA of MKN45 cells treated with As2O3, while control cells showed negative labeling. CONCLUSION: As2O3 can induce apoptosis of human gastric carcinoma cells MKN45, which is the basis of its effectiveness. It shows great potential in the treatment of gastric carcinoma.

Relationship between co-stimulatory molecule B7-H3 expression and gastric carcinoma histology and prognosis

AIM:To investigate the expression of co-stimulatorymolecule B7-H3 in gastric carcinoma and adenomatissue as well as normal gastric tissue and to explore therelationship between B7-H3 expression and pathologicalfeatures and prognosis of gastric carcinoma.METHODS:B7-H3 expression was detected in 102samples of human gastric carcinoma and 10 samples ofgastric adenoma and 10 samples of normal gastric tissueby immunohistochemical assay.Correlation betweenthe expression of B7-H3 and the patients'age,sex,gastric carcinoma locus,tumor size,tissue type,tumorinfiltration depth,differentiation degree,lymph nodemetastasis,and survival time was analyzed.RESULTS:B7-H3 was expressed in all gastric adenomasamples and in 58.8% samples of gastric carcinoma.B7-H3 expression in gastric carcinoma samples wasnot related with the patients'age,sex,lymph nodemetastasis,and tumor size(P>0.05),but with thesurvival time,infiltration depth of tumor and tissue type.CONCLUSION:Detection of B7-H3 expression in gastriccarcinoma tissue is beneficial to the judgment of theprognosis of gastric carcinoma patients and the choice oftreatment.

Study of Sonic hedgehog signaling pathway related molecules in gastric carcinoma

AIM： To study the expression of Sonic hedgehog pathway-related molecules, Sonic hedgehog （Shh） and Glil in gastric carcinoma. METHODS： Expression of Shh in 56 gastric specimens including non-cancerous gastric tissues, gastric adenocarcinoma, gastric squamous cell carcinoma was detected by RT-PCR, in situ hybridization and immunohistochemistry. Expression of Glil was observed by in situ hybridization. RESULTS： The positive rate of Shh and Glil expression was 0.0%, 0.0% in non-cancerous gastric tissues while it was 66.7%, 57.8% respectively in gastric adenocarcinoma, and 100%, 100% respectively in gastric squamous cell carcinoma. There was a significant difference between the non-cancerous gastric tissues and gastric carcinoma （P 〈 0.05）. Elevated expression of Shh and Glil in gastric tubular adenocarcinoma was associated with poorly differentiated tumors while the expression was absent in gastric mucinous adenocarcinoma. CONCLUSION： The elevated expression of Shh and Glil in gastric adenocarcinoma and gastric squamous cell carcinoma shows the involvement of activated Shh signaling in the cellular proliferation of gastric carcinogenesis. It suggests Shh signaling gene may be a new and good target gene for gastric tumor diagnosis and therapy.

Upregulation of hypoxia inducible factor 1α mRNA is associated with elevated vascular endothelial growth factor expression and excessive angiogenesis and predicts a poor prognosis in gastric carcinoma

AIM： To investigate the implication of the hypoxia inducible factor HIF-1α mRNA in gastric carcinoma and its relation to the expression of vascular endothelial growth factor （VEGF） protein, tumor angiogenesis invasion/metastasis and the patient＇s survival. METHODS： In situ hybridization was used to examine expression of HIF-1α mRNA, and immunohistochemical staining was used to examine expression of VEGF protein and CD34 in 118 specimens from patients with gastric carcinoma. RESULTS： The positive rates of HIF-1α mRNA and VEGF protein were 49.15% and 55.92%, respectively. Positive expressions of HIF-1α and VEGF in stage T3-T4 tumors and those with vessel invasion, lymph node metastasis and distant metastasis were dramatically stronger than stage T1-T2 cases and those without vessel invasion, lymph node metastasis and distant metastasis. The mean microvascular density （MVD） in stage T3-T4 tumors and those with vessel invasion, lymph node metastasis and distant metastasis was significantly higher than stage T1-T2 tumors and those without vessel invasion, lymph node metastasis and distant metastasis. The mean MVD in tumors with positive HIF-1α and VEGF expression was significantly higher than that in tumors with negative HIF-1α and VEGF expression. The expression of HIF- 1α was positively correlated with VEGF protein. There were positive correlations between MVD and expression of HIF-1α and VEGF. The mean survival time and the S-year survival rate in cases with positive expression HIF-1α and VEGF and MVD value ≥ 41.5/0.72 mm^2 were significantly lower than those with negative expression of HIF-1α and VEGF and MVD value 〈 41.5/0.72 mm^2. CONCLUSION： Overexpression of HIF-1α is found in gastric carcinoma. HIF-1α may induce the angiogenesis in gastric carcinoma by upregulating the transcription of VEGF gene, and take part in tumor invasion and metastasis. They can be used as prognostic markers of gastric cancer in clinical practice.