A Controversial Tumor Marker: Is SM22 a Proper Biomarker for Gastric Cancer Cells?

详细信息    查看全文

• 作者：Na Li ; Jun Zhang ; Yumei Liang ; Jianmin Shao ; Fuli Peng ; Maomao Sun ; Ningzhi Xu ; Xianghong Li ; Rong Wang ; Siqi Liu ; Youyong Lu
• 刊名：Journal of Proteome Research
• 出版年：2007
• 出版时间：August 2007
• 年：2007
• 卷：6
• 期：8
• 页码：3304 - 3312
• 全文大小：808K
• 年卷期：v.6,no.8(August 2007)
• ISSN：1535-3907

文摘

SM22, a dominant protein in smooth muscle cells (SMCs), has been widely reported to be abnormallyexpressed in many solid tumors. However, the expression patterns of SM22 are not consistent in alltumors, not even in the same ones. Whether SM22 should be considered a tumor biomarker is stilldebated in different laboratories. Herein, we have carried out a systematical investigation to validateSM22 expression in the primary tissues of gastric cancer (GC). Of eight cases, seven samples werefound in the elevated expression of SM22 proteins through proteomic analysis. The observation wasfurther verified by the approaches of Western blotting and quantitative RT-PCR. Surprisingly, the resultsachieved from tissue microarray in 126 GC cases appeared contrary to the proteomic conclusion, inwhich the highly expressed SM22 was mainly found in smooth muscle layers, blood vessels, andmyofibroblasts. This suggested that the increased abundance of SM22 in the cancerous regions wasnot caused by the presence of the GC cells. Furthermore, the expression of SM22 was measured indifferent GC cell lines and SMCs with Western blotting and quantitative RT-PCR. The results revealedthat SM22 expression in SMCs was dramatically higher than that of the GC cells, which indicates thatSM22 is unlikely to be a proper biomarker for GC. Instead, it can be considered a potential indicator forthe abnormal developments of smooth muscles, blood vessels, or myofibroblasts triggered bytumorigenesis.