Analysis of novel collectin, CL-K1 function in colorectal cancer

本研究旨在确定CL-K1在人类胃肠道（GI）恶性肿瘤发生中的表达。我们利用组织阵列检测了CL-K1在正常人和癌组织中的分布。我们还检测了CL-K1在胃和结直肠组织中的分布，并进行了免疫组织化学分析，以确定其在上皮组织和结缔组织中的表达。实时荧光定量PCR和免疫组织化学分析表明，CL-K1在人体内的表达与小鼠相似，在人癌组织中，CL-K1的表达有升高的趋势。我们对42个人胃组织的检查显示，与邻近正常粘膜相比，胃癌组织中CL-K1蛋白的表达较多。此外，在98个人类结直肠组织中，CL-K1的表达随着恶性肿瘤的进展而逐渐增加。此外，CL-K1在侵袭性癌组织中的表达往往高于非侵袭性癌组织。CL-K1在肾脏近端小管、几个器官的血管部分、肝脏的肝细胞和胃肠道的粘膜中表达。令人感兴趣的是，人类的CL-K1表达谱与小鼠相似。在一项140例胃肠道组织标本的研究中，CL-K1上调与恶性肿瘤相关。总之，这些组织学和病理学发现可能有助于进一步了解癌症组织的生物学功能。

The present study aimed to determine CL-K1 expression in tumourigenesis of human gastrointestinal (GI) malignancies. We examined CL-K1 distribution in normal human and cancer tissues by using tissue arrays. We also examined CL-K1 distribution in stomach and colorectal tissue and performed immunohistochemical analyses to determine its expression in epithelial and connective tissues. Real-time PCR and immunohistochemical analyses demonstrated that CL-K1 expression in humans resembles that in mice, and in human cancer tissues, CL-K1 expression tends to be elevated. Our examination of 42 human gastric tissues showed that CL-K1 protein expression was frequently observed in gastric cancer tissues compared with that in adjacent normal mucosa. In addition, in 98 human colorectal tissues, CL-K1 expression showed a significant gradual increase with progression to malignancy. Moreover, CL-K1 expression tended to be higher in invasive cancer tissues than in non-invasive cancer tissues. CL-K1 was expressed in the proximal tubules in the kidneys, vascular portion of several organs, hepatocytes in the liver, and mucosa in the gastrointestinal tract. It is of interest that the CL-K1 expression profile in humans is similar to that in mice. In a study of 140 speciments of GI tract tissues, CL-K1 up-regulation correlated with malignancy. Together, these histological and pathological findings may be useful in furthering our understanding of biological functions in cancer tissues.