Department of Urology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou, China.
Department of Urology, Guangdong NO.2 Provincial People's Hospital, Guangzhou, China.
Int J Cancer. 2019 Mar 15;144(6):1345-1355. doi: 10.1002/ijc.31757. Epub 2018 Nov 4.
LIM kinases modulate multiple aspects of cancer development, including cell proliferation and survival. As the mechanisms of LIMK-associated tumorigenesis are still unclear, we analyzed the tumorigenic functions of LIM kinase 2 (LIMK2) in human bladder cancer (BC) and explored whether the newly identified LIMK2 3´-UTR SNP rs2073859 (G-to-A allele) is correlated with clinical features. Expression levels of LIMK2 in 38 human BC tissues and eight cell lines were examined using quantitative real-time PCR and immunohistochemistry. LIMK2 was overexpressed in most BC tissues (27/38, 71%) and BC-derived cell lines (6/8), and was more frequently overexpessed in high-grade than low-grade BC (80% vs. 47%). The effects of LIMK2 on BC cell proliferation, survival and migration, were studied by overexpression and RNA interference approaches in vitro and in vivo. LIMK2 overexpression promoted proliferation, migration and invasion of BC cells, while LIMK2 depletion inhibited cell invasion and viability and induced growth arrest in vitro and in vivo. PCR-Restriction Fragment Length Polymorphism (RFLP) was used to genotype LIMK2 SNP rs2073859 and multivariate logistic regression applied to assess the relationship between allele frequency and clinical features in 139 BC patients. Functional analyses localized SNP rs2073859 within the microRNA-135a seed-binding region and revealed significantly lower LIMK2 G allele expression. The frequency of A genotypes (AG + AA) was higher in the BC group than normal controls and correlated with risks of high-grade and high-stage BC. In conclusion, LIMK2 may function as an oncogene in human BC, while allele-specific regulation by microRNA-135a may influence disease risk.
LIM 激酶调节癌症发展的多个方面，包括细胞增殖和存活。由于 LIMK 相关肿瘤发生的机制尚不清楚，我们分析了 LIM 激酶 2（LIMK2）在人膀胱癌（BC）中的致瘤功能，并探讨了新鉴定的 LIMK2 3'UTR SNP rs2073859（G 到 A 等位基因）是否与临床特征相关。使用定量实时 PCR 和免疫组织化学分析了 38 个人膀胱癌组织和 8 个细胞系中的 LIMK2 表达水平。LIMK2 在大多数膀胱癌组织（27/38，71%）和膀胱癌衍生的细胞系（6/8）中过表达，在高级别 BC 中比低级别 BC 更频繁地过表达（80%比 47%）。通过体外和体内过表达和 RNA 干扰方法研究了 LIMK2 对 BC 细胞增殖、存活和迁移的影响。LIMK2 过表达促进了 BC 细胞的增殖、迁移和侵袭，而 LIMK2 耗竭抑制了细胞侵袭和活力，并在体外和体内诱导了生长停滞。PCR-限制性片段长度多态性（RFLP）用于对 LIMK2 SNP rs2073859 进行基因分型，并应用多元逻辑回归评估 139 例 BC 患者中等位基因频率与临床特征之间的关系。功能分析将 SNP rs2073859 定位在 microRNA-135a 种子结合区域内，并显示出显著降低的 LIMK2 G 等位基因表达。A 基因型（AG+AA）的频率在 BC 组中高于正常对照组，与高级别和高分期 BC 的风险相关。总之，LIMK2 可能在人膀胱癌中作为癌基因发挥作用，而 microRNA-135a 的等位基因特异性调节可能影响疾病风险。
