MONOCLONAL ANTIBODIES AGAINST HUMAN GASTRIC CANCER

Spleen cells from Balb/c mice immunized with five human gastric cancer cell lines in sequence were fused with murine myeloma cell line SP2/0, and hybridomas 3F4, 3G9 and 3H11, secreting monoclonal antibodiees (MoAbs) against gastric cancer, were obtained through selective culture and screening. These MoAbs have both good selectivity and a high positive rate of reaction for gastric cancer, reaching 5/5 and 84.8% to 93.5% for gastric cancer cells and tissues respectively. The reaction of MoAbs with normal cells and tissues was neglible.The corresponding antigens of the MoAbs were sensitive to digestion by trypsin and pronase and resistant to treatment with sodium periodate, indicating their nature as proteins. The antigen 3G9 could be visualized with Western blotting as two bands with molecular weights of 100KD and 70KD, however no band was found for antigens 3F4 and 3H11. There was a high expression of antigens in the majority of gastric cancer cells and tissues independent of his-topathological type of gastric cancer. A low expression of antigens was seen with other tumors and fetal gastrointestinal tissues. These could be considered as gastric cancer-associated antigens or on-cofetal antigens with a quite extensive distribution.

TUMOR UPTAKE AND THERAPEUTIC EFFECT OF ASTATINATED INTACT McAb 3H11 AND ITS Fab FRAGMENT FOR HUMAN GASTRIC CANCER XENOGRAFT IN NUDE MICE

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Helicobacter pylori——The Cause of Human Gastric Cancer

Background: Many studies documented an association between a Helicobacter pylori infection and the development of human gastric cancer. None of these studies were able to identify Helicobacter pylori as a cause or as the cause of human gastric cancer. The basic relation between gastric cancer and Helicobacter pylori still remains uncertain. Objectives: This systematic review and re-analysis of Naomi Uemura et al. available long-term, prospective study of 1526 Japanese patients are performed so that some new and meaningful inference can be drawn. Materials and Methods: Data obtained by Naomi Uemura et al. who conducted a long-term, prospective study of 1526 Japanese patients with a mean follow up about 7.8 years and endoscopy at enrolment and in the following between one and three years after enrolment were reanalysed. Statistical Analysis Used: The method of the conditio sine qua non relationship was used to proof the hypothesis without a Helicobacter pylori infection no development of human gastric cancer. The mathematical formula of the causal relationship was used to proof the hypothesis, whether there is a cause effect relationship between a Helicobacter pylori infection and human gastric cancer. Significance was indicated by a p-value of less than 0.05. Results: Based on the data published by Uemura et al. we were able to make evidence that without a Helicobacter pylori infection no development of human gastric cancer. In other words, a Helicobacter pylori infection is a conditio sine qua non of human gastric cancer. In the same respect, the data of Uemura et al. provide significant evidence that a Helicobacter pylori infection is the cause of human gastric cancer. Conclusions: Without a Helicobacter pylori infection of human stomach no development of human gastric cancer. Helicobacter pylori is the cause of human gastric cancer (k = +0.07368483, p-value = 0.00399664).

Apoptosis mechanisms of human gastric cancer cell line MKN-45 infected with human mutant p27

AIM: To explore the inducing effect of human mutant p27 gene on the apoptosis of the human gastric cancer cell line MKN-45 and its associated mechanisms. METHODS: The recombinant adenovirus Ad-p27mt was constructed to infect the human gastric cancer cell line MKN-45. Using flow cytometry, TUNEL assay and DNA fragment analysis, we measured the apoptotic effect of Ad-p27mt on the human gastric cancer cells. RESULTS: Ad-p27mt was successfully constructed and the infection efficiency reached 100%. After 18 h of infection, we observed an apoptotic hypodiploid peak on the flow cytometer before G1-S and apoptotic characteristic bands in the DNA electrophoresis. The apoptotic rate detected by TUNEL method was significantly higher in the Ad-p27mt group (89.4±3.12%)compared to the control group (3.12±0.13%, P ＜ 0.01).CONCLUSION: Human mutant p27 can induce apoptosis of the human gastric cancer cells in vitro.

A COMPARISON OF THE PROTOONCOGENES BETWEEN THE HUMAN GASTRIC CANCEROUS AND NORMAL MUCOSAL TISSUES

The allelic distribution of EcoRI and BamHI fragments of ras family genes between the human primary gastric cancer tissues and the corresponding adjacent normal tissues did not show any differences. Three genotypes of BamHI restriction fragment length polymorphism of c-H-ras were revealed. No significant differences in the RFLPs were observed between normal individuals and gastric cancer patients. Four protooncogenes, c-H-ras, N-ras, c-myc and c-fos, were found to be transcriptionally active in the gastric cancer tissues in some cases examined. The comparison of the expression of these oncogenes between the malignant tissues and the corresponding normal tissues showed differential patterns. The expression of c-H-ras at cellular level was detected by in situ hybridization. The enhanced expression of c-H-ras in the gastric cancer cells was demonstrated, but the degree of the expression among the cancer cells was shown to be heterogeneous. In addition, the enhanced expression of c-H-ras was seen in the inflammatory cells.

ULTRASTRUCTURAL CYTOCHEMISTRY OF HUMAN GASTRIC CANCER: ELECTRON MICROSCOPIC OBSERVATIONS OF FIVE ORGANELLAE MARKER ENZYMES

The distribution of ALPase, ACPase, G6Pase TPPase and CCOase of gastric cancer and normal gastric epithelium were studied ultrastructurally. The results showed that normal gastric epithelium had no ALPase reaction. The reactions of ACPase, G6Pase, TPPase and CCOase were found in the corresponding organellae which were cosistent with their functions. In tubular adenocarcinoma cells, their reactions were more apparent in the corresponding organellae. Some cells of tubular adenocarcinomas showed ALPase reaction. The mucinous adenocarcinoma cells had higher ACPase and TPPase reactions. In poorly differentiated adenocarcinoma cells, the five marker enzymes showed negative or faint reactions. The biological significance and mechanisms of distribution of the five marker enzymes were discussed.

Correlation of human epidermal growth factor receptor 2 expression with clinicopathological characteristics and prognosis in gastric cancer

AIM:To investigate human epidermal growth factor receptor 2(HER2) gene amplification and protein expression in Chinese patients with resectable gastric cancer and the association with clinicopathological characteristics and survival.METHODS:One hundred and ninety-seven gastric cancer patients who underwent curative surgery procedures were enrolled into this study.HER2 gene amplification and protein expression were examined using fluorescence in-situ hybridization(FISH) and immunohistochemistry(IHC) analysis on formalin-fixed paraffinembedded gastric cancer samples from all patients.For scoring,Hofmann's HER2 gastric cancer scoring system was adopted.All cases showing IHC3+ or FISH positiv-ity were defined as HER2 positive.Patient clinicopathological data and survival information were collected.Finally,χ 2 statistical analysis was performed to analyze the HER2 positivity rate amongst the subgroups with different clinicopathological characteristics including;gender,age,tumor location,Lauren classification,differentiation,TNM staging,depth of invasion,lymph node metastases and distant metastasis.The probability of survival for different subgroups with different clinicopathological characteristics was calculated using the Kaplan-Meier method and survival curves plotted using log rank inspection.RESULTS:According to Hofmann's HER2 gastric cancer scoring criteria,31 cases(15.74%) were identified as HER2 gene amplified and 19 cases(9.64%) were scored as strongly positive for HER2 membrane staining(3+),25 cases(12.69%) were moderately positive(2+) and 153 cases(77.66%) were HER2 negative(0/1+).The concordance rate between IHC and FISH analyses was 88.83%(175/197).Thirty-six cases were defined as positive for HER2 gene amplification and/or protein expression,with 24 of these cases being eligible for Herceptin treatment according to United States recommendations,and 29 of these cases eligible according to EU recommendations.Highly consistent results were detected between IHC3+,IHC0/1 and FISH(73.68% and 95.42%),but low consistency was observed between IHC2+ and FISH(40.00%).The positivity rates in intestinal type and well-differentiated gastric cancer were higher than those in diffuse/mixed type and poorly-differentiated gastric cancer respectively(28.57% vs 13.43%,P = 0.0103;37.25% vs 11.64%,P < 0.0001),but were not correlated with gender,age,tumor location or TNM stage,depth of invasion,lymph node metastases and distant metastasis.In poorly-differentiated gastric cancer patients,those without lymph node metastasis showed a higher HER2 positivity rate than those with lymph node metastasis(26.47% vs 7.14%,P = 0.0021).This association was not present in thosepatients with well-differentiated gastric cancer(28.57% vs 43.33%,P = 0.2832).Within our patient cohort,26 cases were lost to follow-up.The median survival time for the remaining 171 patients was 18 mo.The median survival times of the HER2 positive and negative groups were 17 and 18.5 mo respectively.Overall survival was not significantly different between HER2-positive and negative groups(χ 2 = 0.9157,P = 0.3386),but in patients presenting well-differentiated tumors,the overall survival of the HER2-positive group was significantly worse than that of the HER2-negative group(P = 0.0123).In contrast,patients with poorly differentiated and diffuse/mixed subtype gastric cancers showed no significant differences in overall survival associated with HER2.Furthermore,the median survival time of the HER2 positive group did not show any statistically significant differences when compared to the subgroups of gender,age,tumor location,TNM classification,lymph node metastases and distant metastasis.CONCLUSION:Patients with intestinal type gastric cancer(GC),well-differentiated GC and poorly-differentiated GC without lymph node metastasis,may all represent suitable candidates for targeted therapy using Herceptin.

Anticancer effect of Jinlongshe granules on in situ-transplanted human MKN-45 gastric cancer in nude mice and xenografted sarcoma 180 in Kunming mice and its mechanism

瞄准：到学习，汉语的反肿瘤效果加重 jinlongshe (JLS ) 肉瘤 180 上的小粒和 MKN-45 人的胃的癌症房间线在活体内和它的机制。方法：在 S180 肉瘤(S180 ) 和胃的癌症裸体老鼠建模的 MKN-45 的建立以后，忍受肿瘤的老鼠在随机被划分成 5 个组。三个试验性的组分别地在 120 g， 60 g 和 20 g/ 的剂量被给 JLS 小粒的水浸膏(kg 每 6/wk， i.g ) 为在 S180 的 3 wk 和在裸体的 6 wk，老鼠当模特儿。积极控制在 50 mg/ 的剂量被给出租机动三轮车磷酰胺(Cy )(kg 每 3/wk， i.g ) 为在 S180 模特儿和 5 氟尿嘧啶(5-FU ) 的 3 wk 20 mg/(kg 每 3/wk， i.g ) 为在裸体的 3 wk，鼠标当模特儿。否定控制在 0.18 g/ 的剂量被给生理盐水(NS )(kg 每 6/wk， i.g ) 分别地。在在忍受 S180 肿瘤的老鼠的 3 wk 和在老鼠建模的裸体的 6 wk 以后，实验动物被牺牲，肿瘤的群众被称，并且每个对待的组的肿瘤抑制的率分别地是计算的。为了决定反肿瘤，机制，词法变化，房间周期和 apoptosis 在老鼠建模的 MKN-45 裸体被观察。Annexin V-FITC/PI 两倍染色的 FCM 试金被用来进一步决定实时房间， apoptotic 房间，坏死的房间和碎片。结果：在 20 g/kg， 60 g/kg 和 120 g/kg 的剂量的 JLS 小粒的禁止的率是 50.31% ， 55.94% 和 68.13%(P 【 0.01 ) 在裸体老鼠模特儿并且 40.90% ， 50.32% 和 58.46%(P 【 0.01 ) 在 S180 模特儿。Cy 的禁止的率在 S180 模特儿是 85.22% ， 5-FU 的禁止的率在老鼠建模的裸体是 53.43%(P 【 0.01 ) 。原子染色质和着边在一台传播电子显微镜(TEM ) 下面被观察。G0/G1 阶段被逮捕的、典型 apoptotic 山峰出现了， apoptotic 率是在三个 JLS 对待小粒的组的 22.81%-38.54% 。两倍染色的 FCM 试金显示出的 Annexin V-FITC/PI apoptotic 房间在三剂量是 4.36% ， 3.08% 和 7.08% ，大多数房间在低正确象限是局部性的。结论：Jinlongshe 小粒在试验性的肿瘤模特儿在活体内，和 apoptosis 正式就职上拥有反肿瘤效果是它的反肿瘤机制之一。

A CT-based radiomics nomogram for prediction of human epidermal growth factor receptor 2 status in patients with gastric cancer

Objective: To develop and validate a computed tomography(CT)-based radiomics nomogram for predicting human epidermal growth factor receptor 2(HER2) status in patients with gastric cancer.Methods: This retrospective study included 134 patients with gastric cancer(HER2-negative: n=87;HER2-positive: n=47) from April 2013 to March 2018, who were then randomly divided into training(n=94) and validation(n=40) cohorts. Radiomics features were obtained from the CT images showing gastric cancer. Least absolute shrinkage and selection operator(LASSO) regression analysis was utilized for building the radiomics signature. A multivariable logistic regression method was applied to develop a prediction model incorporating the radiomics signature and independent clinicopathologic risk predictors, which were then visualized as a radiomics nomogram. The predictive performance of the nomogram was assessed in the training and validation cohorts.Results: The radiomics signature was significantly associated with HER2 status in both training(P<0.001) and validation(P=0.023) cohorts. The prediction model that incorporated the radiomics signature and carcinoembryonic antigen(CEA) level demonstrated good discriminative performance for HER2 status prediction,with an area under the curve(AUC) of 0.799 [95% confidence interval(95% CI): 0.704-0.894] in the training cohort and 0.771(95% CI: 0.607-0.934) in the validation cohort. The calibration curve of the radiomics nomogram also showed good calibration. Decision curve analysis showed that the radiomics nomogram was useful.Conclusions: We built and validated a radiomics nomogram with good performance for HER2 status prediction in gastric cancer. This radiomics nomogram could serve as a non-invasive tool to predict HER2 status and guide clinical treatment.

Clinical significance of human kallikrein 12 gene expression in gastric cancer

AIM:To investigate whether the expression of kallikrein 12(KLK12) is related to the development of gastric cancer(GC) and to determine the role of KLK12 in gastric cancer cells growth,invasion and migration.METHODS:Between September 2007 and March 2008,133 patients with histologically confirmed GC were recruited for the study.Expression of KLK12 was detected in samples from GC patients by quantitative real-time reverse transcription polymerase chain reaction and immunohistochemistry.The relationship between KLK12 protein expression and clinicopathological features of GC was analyzed.The difference in 5-year survival rates between the high KLK12 protein expression group and the low KLK12 expression group was compared.Additionally,the expression of KLK12 was examined in various human GC cell lines,including MKN-28,SGC-7901 and MKN-45.Small interfering RNA(siRNA) was used to inhibit KLK12 expression in MKN-45 cells.Cell clones stably transfected with KLK12 siRNA were tested for KLK12 expression by quantitative real-time reverse transcription-polymerase chain reaction and Western blotting.Furthermore,a series of functional assays were performed in this study to assess the biological features of transfected cells.Cell proliferation was assessed using the methylthiazolyltetrazoliumassay.Finally,cell migration and invasion were assessed using transwell chamber assays.RESULTS:Of the 133 GC patients included in the study,126(94.7%) showed a higher expression level of KLK12 mRNA when compared to noncancerous tissue specimens.Expression of KLK12 mRNA was significantly higher in GC tissues than in normal tissue(P < 0.001).KLK12 protein expression was detected in 96 of 133(72.2%) GC samples with moderate or strong staining primarily in the cytoplasm.In contrast,negative immunostaining for KLK12 protein was observed in the corresponding normal gastric mucosal tissue.Overexpression of KLK12 protein was significantly associated with lymph node metastasis(P = 0.001),histological type(P < 0.001) and tumor-node-metastasis stage(P = 0.005),while no significant correlation was observed between expression of KLK12 protein and sex,age,depth of invasion,tumor size or lymphatic invasion.Furthermore,patients with high KLK12 expression had a significantly poorer 5-year survival rate than those with low KLK12 expression(P = 0.002).Expression of KLK12 mRNA was significantly higher in MKN-45 GC cells compared to normal mucosal cells or two other GC cell lines(P < 0.01).Expression of KLK12 in MKN-45 cells was downregulated after transfection with siRNA.Knockdown of KLK12 markedly decreased the proliferation of MKN-45 cells when compared with parent or mock-transfected cells(P = 0.001),especially from the 3rd to the 5th day of the assay.In migration assays,fewer KLK12 siRNA cells migrated through the chambers(22.00 ± 1.81) when compared to the parent(46.47 ± 2.42) or mock-transfected cells(45.40 ± 1.99);these differences were statistically significant(P < 0.001).However,in the invasion assay,the number of KLK12 siRNA cells that invaded the chambers was 18.40 ± 1.12,closely similar to both the parent(18.67 ± 0.98) and mock-transfected cells(18.53 ± 0.92).There was no significantly difference between the three groups in the invasion assay(P = 0.054).CONCLUSION:The KLK12 gene is markedly overexpressed in GC tissue,and its expression status may be a powerful prognostic indicator for patients with GC.KLK12 might serve as a novel diagnosis and prognosis biomarker in GC.

Potential role of human papilloma virus in the pathogenesis of gastric cancer

AIM:To demonstrate the presence and biological activity of human papilloma virus(HPV)in gastric cancer(GAC)tissues.METHODS:The study involved 84 surgically treated patients with gastric adenocarcinoma,regardless of the clinical stage of the disease.The presence of HPV DNA of high oncogenic risk types in formalin-fixed,paraffinembedded tumor samples was determined using quantitative polymerase chain reaction analysis.A stringentprotocol of prevention of cross-and environmental contamination was applied during DNA isolation,and amplification,as well as confirmation of the biological activity of the virus in tumor cells,was implemented.The study utilized the Real-time High Risk HPV test,which detects the DNA of 14 HPV subtypes that are considered to have high oncogenic potential.The overexpression of the p16INK4a protein assessed immunohistochemically was considered confirmation of the HPV infection.RESULTS:Among the 89 patients initially included in the study group,diagnostic results were obtained for84 individuals.In five cases,either the histopathological material was too scant to isolate the necessary amount of DNA,or the isolated DNA was significantly degraded,resulting in the failure of internal control amplification within the predefined number of 35 cycles.Those patients were excluded from further analysis.The amplification of HPV DNA was demonstrated in none of the84 tissue samples;thus,all cases were considered to have a negative DNA status of highly oncogenic HPV subtypes.Immunohistochemical staining provided diagnostic results for all of the examined tissue samples,and excluded the accumulation of the p16INK4a protein in tumor cells,thus confirming the lack of active HPV infection in all of the individuals.CONCLUSION:The study does not confirm the presence or biological activity of HPV in tumor tissues.Thus,the relationship between GAC and HPV infection,in the Central European population seems doubtful.

A STUDY OF THE STRUCTURE AND THE EXPRESSION OF PROTOONCOGENES IN HUMAN PRIMARY GASTRIC CANCER

The allelic distribution of EcoRI and BamHI fragments of ras family genes between the human primary gastric cancer tissues and the corresponding adjacent normal tissues did not show any differences. Three genotypes of BamHI restriction fragments length polymorphism of c-H-ras were revealed. No significant differences in the RFLPs were observed between normal individuals and gastric cancer patients. Four protooncogenes, c-H-ras, N-ras, c-myc and c-fos, were found to be transcriptionally active in the gastric cancer tissues in some cases examined. The comparison of the expression of these oncogenes between the malignant tissues and the corresponding normal tissues showed differential patterns. The expression of c-H-ras at cellular level was detected with in situ hybridization. The enhanced expression of c-H-ras in the gastric cancer cells was demonstrated, but the degree of the expession among the cancer cells was shown to be heterogeneous. In addition, the enhanced expression of c-H-ras was seen in the inflammatory cells.

Role of human epidermal growth factor receptor 2 in gastric cancer:Biological and pharmacological aspects

Amplification of the human epidermal growth factor receptor 2(HER2)gene and overexpression of the HER2protein is found in 15%-20%of patients with gastric and gastroesophageal junction cancer.The degree of HER2 overexpression and amplification varies with the location of the carcinoma,with higher expression in the gastroesophageal and proximal parts compared to the distal parts of the stomach.Further,HER2 overexpression and amplification also seems to be related to the Lauren histological classification,with higher levels found in the intestinal phenotype compared to the diffuse and mixed types.The prognostic properties of HER2 overexpression and amplification are still under debate,but a large number of studies seem to indicate that HER2 is a negative prognostic factor.The usefulness of HER2 targeted therapy in gastric cancer was demonstrated in the ToGA trial,where HER2-positive patients with advanced gastric and gastroesophageal junction adenocarcinoma were randomized to receive5-FU/capecitabine and cisplatin,either alone or in combination with trastuzumab.A statically significant gain in overall survival was seen in patients who received the combined treatment of trastuzumab and chemotherapy.Patients with a strong overexpression of the HER2 protein(IHC3+)specifically benefited from the treatment,with a median overall survival of 17.9 mo.As a consequence of the positive results of the ToGA trial,patients with advanced gastric or gastroesophageal junction adenocarcinoma are now routinely tested for HER2.The ToGA trial must be characterized as a landmark in the treatment of gastric cancer and it has paved the way for a number of new HER2 targeted compounds such as pertuzumab,ado-trastuzumab emtansine,lapatinib,afatinib,and dacomitinib,which are currently undergoing phaseⅡandⅢclinical testing.Overall,this review will discuss the current status of HER2 in gastric and gastroesophageal junction cancer and the future direction in relation to HER2 target therapy.

Expression of Rab25 correlates with the invasion and metastasis of gastric cancer

The objective of this study was to determine the expression of the important vesicle trafficking- regulating factor Rab25 in human gastric cancer tissues, to analyze the correlation between Rab25 protein expression with gastric cancer occurrence and development, and to discuss the correlation of Rab25 protein expression with gastric cancer cell metastasis. The overall aim was to provide experimental evidence that can be used to design future biological treatments of human gastric cancer. Human gastric cancer tissue and the adjacent normal gastric tissue were surgically removed, and immunohistochemistry and Western blotting were used to detect Rab25 protein expression. The correlation between Rab25 protein expression with the development and pathological characteristics of gastric cancer was analyzed. Using RNAi, Rab25 expression was reduced in the gastric cancer cell line MGC80-3, and the changes in MGC80-3 cell invasiveness were then monitored. Immunohistochemistry showed that the Rab25 protein expression rates were 78.21% and 23.08% in gastric carcinoma and the adjacent normal gastric tissue, respectively. Immunohistochemistry and Western blot results showed that Rab25 protein expression in gastric cancer was significantly higher than in adjacent normal gastric tissues （t）〈0.01）. Less differentiated gastric cancer cells had higher expression of Rab25 protein （P〈0.01）. Gastric carcinomas from patients with a late pathological stage （Ⅲ-Ⅳ） had significantly higher Rab25 protein expression than early stage （Ⅰ-Ⅱ） patients （P〈0.01）. Gastric carcinomas from patients with lymph node metastasis had significantly higher Rab25 protein expression than lymph node metastasis- free patients （P〈0.01）. Gastric carcinomas from patients with distant metastases had significantly higher Rab25 protein expression than the distant metastasis-negative patients （P〈0.01）. Rab25 protein expression in gastric cancer was not affected by the patients＇ sex, age, or tumor size （P〉0.05）. MGCS0-3 cells transfected with Rab25 siRNA had significantly lower Rab25 protein expression （P〈0.01） and a significantly lower number of cells that passed through a Transwell chamber compared with non-transfected controls and the transfected control group （P〈0.01）. Rab25 protein expression is associated with the development of gastric cancer, siRNA knockdown of Rab25 protein expression in MGC80-3 gastric cancer cells reduced MGC80-3 cell invasiveness and provided experimental evidence for potential future biological treatment strategies of human gastric cancer.

Human induced pluripotent stem cells labeled with fluorescent magnetic nanoparticles for targeted imaging and hyperthermia therapy for gastric cancer

Objective: Human induced pluripotent stem(i PS) cells exhibit great potential for generating functional human cells for medical therapies. In this paper, we report for use of human i PS cells labeled with fluorescent magnetic nanoparticles(FMNPs) for targeted imaging and synergistic therapy of gastric cancer cells in vivo. Methods: Human i PS cells were prepared and cultured for 72 h. The culture medium was collected, and then was coincubated with MGC803 cells. Cell viability was analyzed by the MTT method. FMNP-labeled human i PS cells were prepared and injected into gastric cancer-bearing nude mice. The mouse model was observed using a small-animal imaging system. The nude mice were irradiated under an external alternating magnetic field and evaluated using an infrared thermal mapping instrument. Tumor sizes were measured weekly. Results: iP S cells and the collected culture medium inhibited the growth of MGC803 cells. FMNP-labeled human iP S cells targeted and imaged gastric cancer cells in vivo, as well as inhibited cancer growth in vivo through the external magnetic field. Conclusion: FMNP-labeled human i PS cells exhibit considerable potential in applications such as targeted dual-mode imaging and synergistic therapy for early gastric cancer.

Expression of annexin II in gastric carcinoma and its role in gastric cancer metastasis

AIM To investigate the expression of annexin II in gastric carcinoma and its role in the metastasis of gastric cancer.METHODS The expression of annexin II in 51 cases of gastric carcinoma and 24 cases of adjacent tissues was detected by immunohistochemistry. The relationship between annexin II and clinical features of gastric cancer was analyzed. Annexin II specific si RNA was used to inhibit the expression of annexin II in gastric cancer HGC-27 cells, and the effects of annexin II on the migration and secretion of matrix metalloproteinases(MMPs) were observed.RESULTS The positive rate of annexin II protein was 82.4% in gastric cancer tissues and 37.5% in adjacent tissues. There was significant difference between the two groups(P < 0.01); and the positive expression of annexin II was not related to the sex and age of the patients(P > 0.05). The expression of annexin IIprotein was correlated with tumor size, histological differentiation, TNM stage, Lymph node metastasis and other clinical features were significantly correlated, the difference was statistically significant(P < 0.05). Inhibition of annexin II expression, gastric cancer HGC-27 cells migration and secretion of MMPs were significantly decreased, the difference was statistically significant(P < 0.05).CONCLUSION Annexin II is highly expressed in gastric cancer tissues, annexin II protein expression is related to tumor size, histological differentiation, TNM staging, lymph node metastasis and other clinical features were significantly correlated. Annexin II high expression can promote the invasion and metastasis of gastric cancer.

Companion diagnostics for the targeted therapy of gastric cancer

Gastric cancer is the fourth most common type ofcancer and represents a major cause of cancer-related deaths worldwide. With recent biomedical advances in our understanding of the molecular characteristics of gastric cancer, many genetic alterations have been identified as potential targets for its treatment. Multiple novel agents are currently under development as the demand for active agents that improve the survival of gastric cancer patients constantly increases. Based on lessons from previous trials of targeted agents, it is now widely accepted that the establishment of an optimal diagnostic test to select molecularly defined patients is of equal importance to the development of active agents against targetable genetic alterations. Herein, we highlight the current status and future perspectives of companion diagnostics in the treatment of gastric cancer.

HER2 in gastric cancer: Comparative analysis of three different antibodies using whole-tissue sections and tissue microarrays

AIM:To compare the performance of three commercially available anti-human epidermalgrowth factor receptor 2(HER2)antibodies in whole-tissue sections and tissue microarrays(TMAs)of a series of gastric tumors.METHODS:We present a comparative analysis of three anti-HER2 antibodies(HercepTest,4B5 and SP3)using TMA and whole-tissue sections prepared from the same paraffin blocks of 199 gastric adenocarcinomas operated upon between January 2004 and December2008 at a Brazilian cancer hospital.The data on the patients’age,sex,the anatomical location of the tumor and the Lauren’s histological classification were collected from clinical and pathological records.The immunohistochemical(IHC)results were examined by two pathologists and the cases were classified as positive(3+),equivocal(2+)and negative(0 or 1+),according to the criteria of the IHC scoring system of gastric cancer.TMAs and whole-tissue sections were evaluated separately and independently.All cases yielding discordant IHC results and/or scored as 2+were subjected to dual-color in situ hybridization in order to determine the final HER2 status.Besides determining the sensitivity and predictive value for HER2-positive status,we measured the accuracy of each antibody by calculating the area under the receiver operating characteristic(ROC)curve.The agreement between the results obtained using the TMAs and those obtained using the whole-tissue sections was assessed by means of Kappa coefficient.RESULTS:Intratumoral heterogeneity of HER2 expression was observed with all antibodies.HER2-positive expression(3+)in the whole-tissue sections was observed in 23 cases(11.6%)using the 4B5 antibody,in 18 cases(9.1%)using the SP3 antibody and in 10 cases(5.1%)using the HercepTest antibody.In the TMAs,11 positive cases(5.6%)were identified using SP3 antibody,9(4.6%)using the 4B5 antibody and 6(3%)using the HercepTest antibody.The sensitivity using whole-tissue sections and TMA,respectively,was 95.2%and 42.9%with 4B5,90.5%and 66.7%with SP3 and 47.6%and42.9%with HercepTest.The accuracy,calculated from the area under the ROC curve,using whole-tissue sections and TMA,respectively,was 0.91 and 0.79 by 4B5,0.86 and 0.80 by SP3 and 0.73 and 0.71 by HercepTest.The concordance of the results obtained using wholetissue sections and TMA was 97.4%(Kappa 0.75)using HercepTest,85.6%(Kappa 0.56)using SP3 and 84.1%(Kappa 0.38)using 4B5.CONCLUSION:The use of the 4B5 antibody on wholetissue sections was the most accurate IHC method for evaluating HER2 expression in gastric adenocarcinoma.

Telomerase and hTERT: Can they serve as markers for gastric cancer diagnosis?

AIM:To investigate telomerase activity and human telomerase reverse transcriptase(hTERT)expression in normal human gastric mucosal epithelial cells(nhGMECs)and fibroblasts(nhGMFs).METHODS:nhGMECs and nhGMFs were isolated and cultured from specimens obtained during routine surgery for bleeding peptic ulcer.Telomerase activity in nhGMFs,nhGMECs,and the tumor cell lines BGC-823,SGC-7901 and MKN-28 cells was analyzed using the telomeric repeat amplification protocol assay.hTERT protein was determined in nhGMECs,nhGMFs,BGC-823,SGC-7901 and MKN-28 cells by indirect immunofluorescence.served in nhGMECs,nhGMFs and BGC-823,SGC-7901,MKN-28 cell lines.Positive hTERT immunostaining was detected in nhGMECs,nhGMFs,BGC-823,SGC-7901and MKN-28 cell lines.CONCLUSION:The use of telomerase or hTERT as diagnostic markers for gastric cancer may require further studies.

Association of HER2 status with prognosis in gastric cancer patients undergoing R0 resection: A large-scale multicenter study in China

AIM: To determine whether the positive status of human epidermal growth receptor 2(HER2) can be regarded as an effective prognostic factor for patients with gastric cancer(GC) undergoing R0 resection.METHODS: A total of 1562 GC patients treated by R0 resection were recruited. HER2 status was evaluated in surgically resected samples of all the patients using immunohistochemical(IHC) staining. Correlations between HER2 status and clinicopathological characteristics were retrospective analyzed. Hazard ratios(HRs) and 95% confidence intervals(CIs) were estimated using Cox proportional hazard model, stratified by age, gender, tumor location and tumor-nodemetastasis(TNM) stage, with additional adjustment for potential prognostic factors.RESULTS: Among 1562 patients, 548(positive rate = 35.08%, 95%CI: 32.72%-37.45%) were HER2 positive. Positive status of HER2 was significantly correlated with gender(P = 0.004), minority(P < 0.001), tumor location(P = 0.001), pathological grade(P < 0.001), TNM stage(P < 0.001) and adjuvant radiotherapy(74.67% vs 23.53%, P = 0.011). No significant associations were observed between HER2 status and disease free survival(HR = 0.19, 95%CI: 0.96-1.46, P = 0.105) or overall survival(HR = 1.19, 95%CI: 0.96-1.48, P = 0.118) using multivariate analysis, although stratified analyses showed marginally statistically significant associations both in disease free survival and overall survival, especially among patients aged < 60 years or with early TNM stages(Ⅰ and Ⅱ). Categorical age, TNM stage, neural invasion, and adjuvant chemotherapy were, as expected, independent prognostic factors for both disease free survival and overall survival. CONCLUSION: The positive status of HER2 based on IHC staining was not related to the survival in patients with GC among the Chinese population.