肺癌细胞自分泌collagenⅠ在三维培养中促进肺癌细胞的生长

TypeⅠcollagen secreted by lung cancer cells promotes cancer cell growth in a three-dimensional culture system

目的研究肺癌细胞自分泌的胶原Ⅰ型(collagenⅠ)在肺癌细胞三维培养的作用。方法通过免疫组化和RT-PCR证实肺癌细胞表达collagenⅠ;采用sh-collagenⅠ方法干扰肺癌细胞的表达,正常肺癌细胞作为对照组;用成纤维细胞的上清液刺激肿瘤,RT-PCR检测collagenⅠ的表达。结果肺癌细胞分泌collagenⅠ;发现敲除collagenⅠ的肺癌细胞的三维生长受到限制:其生长率下降,三维培养中克隆形成减少。采用成纤维细胞培养细胞上清液刺激肿瘤细胞,肺癌肿瘤细胞自分泌的collagenⅠ表达发生改变,肿瘤自分泌的collagenⅠ可以维持自身生长的需要并受到微环境中非细胞外基质的调控。结论肺癌细胞自分泌的collagenⅠ对肿瘤的生长有着重要作用。

Objective To investigate the role of type I collagen as an autocrine protein in promoting the growth lung cancer cells in a three-dimensional （3D） culture system. Methods Immunohistochemistry and RT-PCR were used to detect the expression of type I collagen in lung cancer specimens and 5 lung cancer cell lines. The lung cancer cell lines in 3D cultures were treated with vectors harboring short hairpin RNA （shRNA） targeting type I collagen, and the cell growth suppression was evaluated using MT~ assay and colony formation assay. The lung cancer cells stimulated with supernatant from lung cancer-derived fibroblasts were tested for the expression of type I collagen mRNA. Results Type I collagen expressions were detected in both the lung cancer tissues and the cell lines. In the 3D culture system, the growth of the cancer ceil lines was obviously suppressed by shRNA-mediated type I collagen knockdown evidenced by lowered cell growth rate and colony formation ability. Stimulation with fibroblast culture supernatant resulted in enhanced expressions of type I collagen in the cancer cell lines. Conclusion Autocrine of type I collagen I is required for maintaining lung cancer cell growth in 3D cultures, and its expression is regulated by fibroblasts. These findings provide new insights into the role of type I collagen I in the tumor microenvironment and point a new direction for targeted therapy of tumors.