Background and objective: Decorin is a protein component of the extracellular matrix. It has been proven that decorin plaid an important role in matrix assembly. The protein is also capable of suppressing tumor cell growth. The aim of this study is to examine the protein levels of decorin in tissue samples of non-small cell lung cancer (NSCLC) patients and evaluate its potential clinical value.
Methods: Decorin protein levels in tumor tissues and corresponding normal tissues from 16 cases of lung squamous cell carcinoma (SCC) were determined by Western blot analysis. Fifty-one NSCLC samples, including both tumor and normal lung tissues, were examined by immunohistochemical (IHC) staining.
Results: Western blot results showed that decorin protein levels in 75.0% (12/16) of the SCC tumor tissues were lower than those of the corresponding normal lung tissues. IHC results showed that positively stained decorin was detected in only 11.8% of the tumor tissues, significantly lower than that observed in normal alveoli tissues (53.1%, P<0.001). In lung adenocarcinoma (ADC), almost no expression of decorin was observed, in contrast to squamous cell carcinoma (SCC) (P=0.006).
Conclusion: Decreased levels of decorin in NSCLC tissue samples, particularly ADC cases, indicate that decorin could play a role in lung cancer carcinogenesis.
背景与目的: 核心蛋白聚糖（decorin）是细胞外基质（extracellular matrix, ECM）的组成成分，参与抑制胶原纤维形成、调控细胞的增殖和粘附等过程。本研究检测非小细胞肺癌（non-small cell lung cancer, NSCLC）患者肿瘤组织中decorin的蛋白水平，并研究其作为肿瘤抑制因子与各临床指标的关系及其意义。
方法: 采用Western blot方法检测16例肺鳞癌患者的肿瘤组织及其配对正常肺组织中decorin蛋白水平。采用免疫组织化学染色的方法检测51例NSCLC患者的肿瘤组织和正常肺组织中decorin蛋白水平。
结果: Western blot结果表明相对于癌旁肺组织，12例（75.0%）肺癌组织中decorin的蛋白表达水平明显下调。Decorin在肺癌的肿瘤组织表达阳性率仅为11.8%，明显低于正常肺泡组织（阳性率为53.1%，P < 0.001）。并且，decorin在肺腺癌组织中几乎不表达（阳性率为0），与肺鳞癌组织相比有统计学差异（阳性率为24.0%，P=0.006）。
结论: NSCLC肿瘤组织中decorin蛋白水平明显降低并与病理类型相关，提示decorin的异常下调可能在肺腺癌的发生发展过程中发挥作用。