Study of miRNA regulatory systems of antitumor effects by human cathelicidin.

(1)hCAP 18/LL-37是目前唯一从人体中发现的cathelichidins家族抗菌肽。我们报道了Cathelicidin抑制MMP-9的炎症活性，从而抑制肿瘤细胞的侵袭和转移。此外，miRNA微阵列用于鉴定MMP-9调节的miRNA，miR-4327。总之，Cathelicidin通过miR-4327调节MMP-9的表达。(2)我们检测了LL-37肽在血管生成中的作用。在血管抑制条件下，LL-37肽剂量依赖性地抑制HMVECs管腔形成。相比之下，在促血管生成条件下，LL-37肽诱导与对照相比管形成增加2.6倍。此外，miRNA微阵列用于鉴定LL-37调节的miRNA。LL-37在血管生成抑制条件下可诱导miR-3188的表达，在促血管生成条件下可诱导miR-582- 5 p的表达。

(1) hCAP18/LL-37 is the only antimicrobial peptide of the cathelichidins family identified from human. We reported Cathelicidin inhibits the enzumatic activity of MMP-9, thereby repressing tumor cell invasion and metastasis. In addition, miRNA microarrays were used to identify MMP-9-regulated miRNA, miR-4327. In conclusion, Cathelicidin regulates MMP-9 expression via miR-4327.(2) We examined the effect of LL-37 peptide in angiogenesis. In angiostatic condition, LL-37 peptide inhibited the tube formation of HMVECs in dose dependently. By contrast, in proangiogenic condition, LL-37 peptide induced a 2.6-fold increase in tube formation compared with control. Additionally, miRNA microarrays were used to identify LL-37-regulated miRNA. In angiostatic condition, LL-37 could induce expression of miR-3188 and in proangiogenic condition, LL-37 could induce expression of miR-582-5p.In conclusion, LL-37 has angiostatic and proangiogenic activity in vascular endothelial cells.