Tumorigenicity, invasion, and metastasis of human gastric cancer in nude mice

Clinical utility of miniprobe endoscopic ultrasonography for prediction of invasion depth of early gastric cancer: A meta-analysis of diagnostic test from PRISMA guideline

BACKGROUND

Recently, some studies assessed the clinical utility of miniprobe endoscopic ultrasonography for prediction of invasion depth of early gastric cancer (GC). However, the results remain inconsistent.

OBJECTIVES

We conducted a meta-analysis to assess the clinical utility of miniprobe endoscopic ultrasonography for diagnostic of invasion depth of early GC.

METHODS

We systematically searched several online electronic databases including PubMed, China National Knowledge Infrastructure, Web of Science, Embase, and Wanfang from initial library to July 20, 2018, identifying the study about miniprobe endoscopic ultrasonography for diagnostic of invasion depth of early GC. Bivariate mixed effects models were used to calculate the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) with theirs 95% confidence intervals (CIs).

RESULTS

Nineteen studies with 3401 patients were included in the meta-analysis. The bivariate mixed effect model indicated that the overall diagnostic sensitivity was 0.86 (95%CI: 0.79-0.91) and the specificity was 0.73 (95%CI: 0.66-0.78). The area under the curve was 0.84 (95%CI: 0.81-0.87). We also estimated the other pooled parameters as follows: the pooled PLR was 3.13 (95%CI: 2.55-3.84), the pooled NLR was 0.19 (95%CI: 0.13-0.28), the diagnostic score was 2.78 (95%CI: 2.33-3.23), and the diagnostic odds ratio was 16.1 (95%CI: 10.23-25.36). Subgroup analysis indicated that ethnicity may be the decisive factor on heterogeneity.

CONCLUSIONS

The present study indicated that the miniprobe endoscopic ultrasonography had a moderate diagnostic ability for invasion depth of early GC. The diagnostic utility was influenced by ethnicity. Further research is required to confirm the present findings and explore the potential factors of heterogeneity.

OB glue paste technique for establishing nude mouse human gastric cancer orthotopic transplantation models

AIM: To establish nude mouse human gastric cancer orthotopic transplantation models using OB glue paste technique.

METHODS: Using OB glue paste technique, orthotopic transplantation models were established by implanting SGC-7901 and MKN-45 human gastric cancer cell strains into the gastric wall of nude mice. Biological features, growth of the implanted tumors, the success rate of transplantation and the rate of auto-metastasis of the two models were observed.

RESULTS: The success rates of orthotopic transplan-tation of the two models were 94.20% and 96%. The rates of hepatic metastasis, pulmonary metastasis, peritoneal metastasis, lymphocytic metastasis and splenic metastasis were 42.13% and 94.20%, 48.43% and 57.97%, 30.83% and 36.96%, 67.30% and 84.06%, and 59.75% and 10.53%, respectively. The occurrence of ascites was 47.80% and 36.96%.

CONCLUSION: OB glue paste technique is easy to follow. The biological behaviors of the nude mouse human gastric cancer orthotopic transplantation models established with this technique are similar to the natural processes of growth and metastasis of human gastric cancer, and, therefore, can be used as an ideal model for experimental research of proliferative metastasis of tumors.

The invasion-MTT assay as a predictor of liver metastasis using human gastrointestinal carcinomas transplanted in nude mice

The invasion-3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay, which evaluates invasive potential into the reconstituted basement membrane, Matrigel, was performed on 49 human gastrointestinal carcinomas transplanted in nude mice. There were 19 colorectal carcinomas, 10 pancreatic carcinomas, 10 gastric carcinomas, 8 esophageal carcinomas, and 2 bile duct carcinomas. The percent invasion (PI) value of each tumor by the invasion-MTT assay expresses the invasive rate of tumor cells into the Matrigel as a percentage. There were no significant differences in correlations between the PI values and primary tumor site, clinicopathological findings, tumor doubling time, or DNA index; however, the PI values of primary tumors and lymph nodes with liver metastases were significantly higher than those of primary tumors without liver metastasis (P < 0.05). Furthermore, the primary tumors with synchronous (P < 0.05) or asynchronous (P < 0.01) liver metastases showed significantly higher PI values compared with the primary tumors without liver metastases. These results suggest that PI is not only an independent factor to predict liver metastasis, but it also correlates closely with liver metastasis. Thus, the invasion-MTT assay for primary tumors might be clinically useful to predict liver metastasis in patients following surgery for gastrointestinal carcinomas.

Establishment and characterization of two cell lines derived from human diffuse gastric carcinomas xenografted in nude mice

Two human diffuse gastric carcinoma cell lines were established in vitro from xenografted tumours serially passaged in nude mice. Of 12 primary diffuse gastric carcinomas, 7 were successfully xenografted in nude mice (58.3%). Short-term primary cultures were achieved in all the xenografted lines. However, only 2 of the 7 short-term primary cultures were established as long-term cultures (GP202 and GP220). GP202 cells are larger than GP220 cells, show less abundant intercellular junctions at the ultrastructural level and grow in culture as a compact thin monolayer. The GP220 cells grow preferentially in small clusters attached to the monolayer, with a subpopulation of floating cells. Both lines have cells containing small mucin vacuoles in the cytoplasm and cells displaying a typical signet-ring shape. GP202 cells grow as solid tumours in nude mice but GP220 cells do not give rise to tumours. The flow cytometry and karyotype analysis showed aneuploidy in GP202 cells, with many numerical and structural chromosomal abnormalities, and diploidy in GP220 cells, with several structural chromosomal abnormalities. The CDw75 and Tn antigens are more prominently expressed in GP202 cells than in GP220 cells. T antigen is only expressed in GP202 cells, whereas only GP220 cells express EGFR. Sialosyl-Tn is not expressed in either of the cell lines. The gastric cancer cell lines described in this paper represent a valuable addition to the small number of diffuse gastric cancer cell lines currently available and also provide a good model for further in vitro and in vivo studies of gastric carcinogenesis.

Monoclonal antibodies against a human gastric cancer cell line with lung metastatic potential in nude mice define antigens with different expression between the primary and metastatic liver lesions

SCK-29 is a tumor cell line derived from human gastric adenocarcinoma with the feature of producing lung metastases when xenografted in nude mice. Monoclonal antibodies were produced against SCK-29 tumor cells or their glycoproteins prepared by affinity chromatography on a lectin-agarose column. Five antigens defined by the monoclonal antibodies MG-1 to MG-5 were expressed in a large number of gastric or colonic adenocarcinomas. Among the antigens, MG-1 and MG-3 proved to be tumor-associated, since they were detected only occasionally in normal tissues. MG-5 antigen was often detected in normal gastric mucosa but not in other tissues. The degree of expression of MG-1. MG-3 and MG-5 antigens differed considerably in metastatic lesions. In metastatic liver lesions of gastric adenocarcinoma, expression of these MG antigens was less marked than in primary tumors. MG-1 and MG-3 antigens were abolished by neuraminidase digestion and periodate oxidation. MG-5 antigen was likely to be a protein antigen, since it was resistant to neuraminidase digestion and to periodate oxidation but was sensitive to protease digestion.