The novelty of profilin 2 in regulating pyruvate kinase M2 nuclear translocation and promoting tumor angiogenesis in lung adenocarcinoma.

Background: Profilin 2 (PFN2), indispensable in all organisms, is important for cancer initiation and progression. Here, we found PFN2 highly overexpressed in tumor tissues with poor prognosis of Lung adenocarcinoma (LUAD) patients had a novel role in remodulating angiogenesis. However, the mechanism of PFN2-mediated LUAD angiogenesis remains unelucided.

Methods: Immunohistochemistry and western blotting were used to detected the expression levels of related proteins in tissue or lung cancer cells. To elucidate the underlying mechanisms, we identified binding partners of PFN2 through mass spectrometry, co-immunoprecipitation, and molecular modeling techniques. Additionally, we investigated the angiogenic-promoting function of PFN2 utilizing a three-dimensional droplet-based angiogenesis model capable of simulating the tumor hypoxic microenvironment.

Results: Our finding reveal that PFN2 was overexpressed in tumors compared with the adjacent nontumor tissues. Its knockdown markedly impaired the proliferation, and angiogenesis of LUAD cells via hypoxia-related NF-κB/HIF-1α signaling pathway, with vascular endothelial growth Factor (VEGF) decrease. Additionally, pyruvate kinase M2 (PKM2), a pivotal enzyme in glycolysis, is a novel binding partner of PFN2. The nuclear translocation of PKM2 was observed to be dependent on PFN2 expression and their interaction, which functionally modulates angiogenesis in lung cancer.

Conclusions: Our study revealed oncogene PFN2 promoted tumor angiogenesis in LUAD through regulating PKM2 nuclear translocation, providing novel molecular therapy targets for LUAD treatment.