Nischarin regulates focal adhesion and Invadopodia formation in breast cancer cells
MOLECULAR CANCER
Authors: Maziveyi, Mazvita; Dong, Shengli; Baranwal, Somesh; Alahari, Suresh K.
Abstract
Background: During metastasis, tumor cells move through the tracks of extracellular matrix (ECM). Focal adhesions (FAs) are the protein complexes that link the cell cytoskeleton to the ECM and their presence is necessary for cell attachment. The tumor suppressor Nischarin interacts with a number of signaling proteins such as Integrin a5, PAK1, LIMK1, LKB1, and Rac1 to prevent cancer cell migration. Although previous findings have shown that Nischarin exerts this migratory inhibition by interacting with other proteins, the effects of these interactions on the entire FA machinery are unknown. Methods: RT-PCR, Western Blotting, invadopodia assays, and immunofluorescence were used to examine FA gene expression and determine whether Nischarin affects cell attachment, as well as the proteins that regulate it. Results: Our data show that Nischarin prevents cell migration and invasion by altering the expression of key focal adhesion proteins. Furthermore, we have found that Nischarin-expressing cells have reduced ability to attach the ECM, which in turn leads to a decrease in invadopodia-mediated matrix degradation. Conclusions: These experiments demonstrate an important role of Nischarin in regulating cell attachment, which adds to our understanding of the early events of the metastatic process in breast cancer.
Gene expression profiling of lung adenocarcinoma in Xuanwei, China
EUROPEAN JOURNAL OF CANCER PREVENTION
Authors: Wu, Huifei; Meng, Shuangshuang; Xu, Qiuyue; Wang, Xiao; Wang, Juan; Gong, Rong; Song, Yu; Duan, Yong; Zhang, Yanliang
Abstract
The morbidity and mortality of lung cancer in Xuanwei, China, are the highest in the world. This study attempts to identify differentially expressed genes (DEGs) related to lung adenocarcinoma in Xuanwei. The expression profiles of eight paired lung adenocarcinoma tissues and corresponding nontumor tissues were acquired by microarrays. Functional annotations of DEGs were carried out by bioinformatics analysis. The results of the microarrays were further verified by real-time quantitative PCR (RTq-PCR). A total of 5290 genes were classified as DEGs in lung adenocarcinoma in Xuanwei; 3325 genes were upregulated and 1965 genes were downregulated, whereas the expression of the other 11970 genes did not change. These DEGs are involved in a wide range of cancer-related processes, which include cell division, cell adhesion, cell proliferation, and DNA replication, and in many pathways such as the p53 signaling pathway, the MAPK pathway, the Jak-STAT signaling pathway, the hedgehog signaling pathway, and the non-small-cell lung cancer pathway. The tendency of changes in the expression of 12 selected DEGs (five downregulated genes, PIK3R1, RARB, HGF, MAPK11, and SESN1, and seven upregulated genes, PAK1, E2F1, CCNE1, EGF, CDC25A, PTTG1, and UHRF1) in RTq-PCR was consistent with the expression profiling data. Expression of PAK1 was significantly increased in the low differentiation group (P=0.031), whereas expression of HGF was significantly decreased in the low differentiation group (P=0.045). RARB and MAPK11 were significantly increased in the nonsmoker group (P=0.033 and 0.040, respectively). A large number of DEGs in lung adenocarcinoma in Xuanwei have been detected, which may enable us to understand the pathogenesis and lay an important foundation for the prevention and treatment of lung adenocarcinoma in Xuanwei.