Expression And Significance Of S100A4, S100A9and S100P In Gastric Cancer

Research objectiveTo investigate the expression of S100A4，S100A9and S100P protein inhuman gastric cancer tissues and paired adjacent tissues, to analyse therelevance between the expressions of these three proteins and the commontumor markers such as CEA and CA-199in serum and to discuss the clinicalsignificance of these proteins.Research methodEighty-two gastric cancer samples and their matched normal tissues fromeighty-two patients who were diagnosed with gastric cancers in our hospitalfrom August2010to May2011were selected as the objects of this study. Clinical operation specimen of them were collected and their related clinicaldatas including age, gender, family history, the state of radiotherapy andchemotherapy prior to surgery, primary tumor size and staging, histologicalpattern, degree of differentiation and infiltration and situation of lymph nodemetastasis were statistically analysed. The relationship between above indexand the expression level of S100A4, S100A9and S100P were analysed.Immunohistochemical staining was used to detect the expression ofS100A4, S100A9and S100P in gastric cancer samples and paired normaltissues. Enzyme linked immunosorbent assay (ELISA) was used to detect thelevel of gastric cancer related tumor markers (CEA and CA19-9) in serum. Atlast, the relevance between the expression levels of S100A4, S100A9andS100P and these tumor markers were analysed.ResultThere were sixty men and twenty-two women gastric cancer patients inour study and their average age was sixty-two years. In regard to theirhistopathological classification, seventy-four cases were adenocarcinoma and eight cases were signet-ring cell carcinoma. In these eight-two samples, elevenwere well differentiated, twenty-five were media differentiated and forty-sixwere poorly differentiated. TNM classification(2010) was applied to identifythe tumor staging in our research. Thirteen cases were Ⅰstaging, seventeenones were Ⅱ staging, forty-nine ones were Ⅲstaging and three ones were Ⅳstaging. The rate of expressing for S100A4protein in adjacent tissues was3.6%(3/82), while in gastric cancer tissues it was52.4%(43/82). The rate ofexpressing for S100A9protein in adjacent tissues was6.1%(5/82), while itwas59.8%(49/82) in gastric cancer tissues. The rate of expressing for S100Pprotein in adjacent tissues was86.6%(71/82), while in gastric cancer tissues itwas52.4%(43/82). There was no significant correlation between the positiveexpression of S100A4、S100A9and S100P proteins in gastric cancer tissuesand patients’ gender, age, tumor sizes and the differentiation of tumor cells (p＞0.05). The positive expression of S100A4protein was associated with thetumors invasion depth, lymph node metastasis and their advanced staging (p＜0.05).(Table1) Similarly, the positive expression of S100A9protein was alsoassociated with gastric cancers invasion depth, lymph node metastasis and staging classification (p＜0.05), and it was also related to the degree of celldifferentiation.(Table4)The downregulation of S100P expression and thetumors invasion depth, lymph node metastasis and their advanced staging waspositively correlated (p＜0.05).(Table9)There was no significant correlation between the expressions of S100A4,S100A9and S100P proteins and the level of tumor biomarkers related withgastric cancer such as CEA and CA-199in serum.ConclusionThe expression of S100A4and S100A9proteins in gastric cancer tissueswas higher than that in adjacent normal tissues, while the expression of S100Pwas downregulated in gastric cancer tissues. The expressions of these threeproteins was irrelevant to the gender and age of patients and the size of tumors.The expression of S100A4protein was associated with the tumors invasiondepth, lymph node metastasis and their advanced staging (p＜0.05). Theexpression of S100A9protein was associated with gastric cancers invasiondepth, degree of differentiation, lymph node metastasis and staging classification (p＜0.05). The downregulation of S100P was associated with thetumors invasion depth, lymph node metastasis and their advanced staging (p＜0.05).