Beta-Pix-dynamin 2 complex promotes colorectal cancer progression by facilitating membrane dynamics

• Published in: Cellular oncology (Dordrecht) 2021-12, Vol.44 (6), p.1287-1305
• Main Authors: Keum, Seula, Yang, Soo Jung, Park, Esther, Kang, TaeIn, Choi, Jee-Hye, Jeong, Jangho, Hwang, Ye Eun, Kim, Jung-Woong, Park, Dongeun, Rhee, Sangmyung
• Format: Article
• Language: English
• Subjects: Actin; Amino Acid Sequence; Biomedical and Life Sciences; Biomedicine; Cancer; Cancer Research; Cell adhesion & migration; Cell Line, Tumor; Cell Membrane - metabolism; Cell membranes; Cell migration; Cell Movement - genetics; Colorectal cancer; Colorectal carcinoma; Colorectal Neoplasms - metabolism; Colorectal Neoplasms - pathology; Disease Progression; Dynamin; Dynamin II - chemistry; Dynamin II - metabolism; Gene Expression Regulation, Neoplastic; Gold - chemistry; Guanine; Guanine nucleotide exchange factor; HEK293 Cells; Homology; Humans; Immunocytochemistry; Immunoprecipitation; Kinases; Lamellipodia; Localization; Matrix metalloproteinase; Matrix Metalloproteinase 14 - metabolism; Metal Nanoparticles - chemistry; Metalloproteinase; Molecular modelling; Neoplasm Invasiveness; Oncology; Original; Original Article; Pathology; Phosphorylation; Phosphotyrosine - metabolism; Proline; Protein Binding; Pseudopodia; Pseudopodia - metabolism; rac1 GTP-Binding Protein - metabolism; Rac1 protein; Rho Guanine Nucleotide Exchange Factors - chemistry; Rho Guanine Nucleotide Exchange Factors - metabolism; RNA, Messenger - genetics; RNA, Messenger - metabolism; src Homology Domains; Tyrosine; Up-Regulation
• ISSN: 2211-3428; 2211-3436
• DOI: 10.1007/s13402-021-00637-6

Purpose Spatiotemporal regulation of cell membrane dynamics is a major process that promotes cancer cell invasion by acting as a driving force for cell migration. Beta-Pix (βPix), a guanine nucleotide exchange factor for Rac1, has been reported to be involved in actin-mediated cellular processes, such as cell migration, by interacting with various proteins. As yet, however, the molecular mechanisms underlying βPix-mediated cancer cell invasion remain unclear. Methods The clinical significance of βPix was analyzed in patients with colorectal cancer (CRC) using public clinical databases. Pull-down and immunoprecipitation assays were employed to identify novel binding partners for βPix. Additionally, various cell biological assays including immunocytochemistry and time-lapse video microscopy were performed to assess the effects of βPix on CRC progression. A βPix-SH3 antibody delivery system was used to determine the effects of the βPix-Dyn2 complex in CRC cells. Results We found that the Src homology 3 (SH3) domain of βPix interacts with the proline-rich domain of Dynamin 2 (Dyn2), a large GTPase. The βPix-Dyn2 interaction promoted lamellipodia formation, along with plasma membrane localization of membrane-type 1 matrix metalloproteinase (MT1-MMP). Furthermore, we found that Src kinase-mediated phosphorylation of the tyrosine residue at position 442 of βPix enhanced βPix-Dyn2 complex formation. Disruption of the βPix-Dyn2 complex by βPix-SH3 antibodies targeting intracellular βPix inhibited CRC cell invasion. Conclusions Our data indicate that spatiotemporal regulation of the Src-βPix-Dyn2 axis is crucial for CRC cell invasion by promoting membrane dynamics and MT1-MMP recruitment into the leading edge. The development of inhibitors that disrupt the βPix-Dyn2 complex may be a useful therapeutic strategy for CRC.