AIMP2-DX2 provides therapeutic interface to control KRAS-driven tumorigenesis.

Recent development of the chemical inhibitors specific to oncogenic KRAS (Kirsten Rat Sarcoma 2 Viral Oncogene Homolog) mutants revives much interest to control KRAS-driven cancers. Here, we report that AIMP2-DX2, a variant of the tumor suppressor AIMP2 (aminoacyl-tRNA synthetase-interacting multi-functional protein 2), acts as a cancer-specific regulator of KRAS stability, augmenting KRAS-driven tumorigenesis. AIMP2-DX2 specifically binds to the hypervariable region and G-domain of KRAS in the cytosol prior to farnesylation.

Noncanonical roles of membranous lysyl-tRNA synthetase in transducing cell-substrate signaling for invasive dissemination of colon cancer spheroids in 3D collagen I gels.

The adhesion properties of cells are involved in tumor metastasis. Although KRS at the plasma membrane is shown important for cancer metastasis, additionally to canonical roles of cytosolic KRS in protein translation, how KRS and its downstream effectors promote the metastatic migration remains unexplored. Disseminative behaviors (an earlier metastatic process) of colon cancer cell spheroids embedded in 3D collagen gels were studied with regards to cell adhesion properties, and relevance in KRS(-/+) knocked-down animal and clinical colon cancer tissues.

Chemical suppression of an oncogenic splicing variant of AIMP2 induces tumour regression.

AIMP2 (aminoacyl-tRNA synthetase-interacting multifunctional protein 2) is a potent tumour suppressor that induces apoptosis in response to various oncogenic signals. AIMP2-DX2, an exon2-deleted splicing variant of AIMP2, is up-regulated in lung cancer and competitively suppresses the pro-apoptotic activity of AIMP2, resulting in tumorigenesis. In the present study we report that BC-DXI01, a synthetic compound, specifically reduces the cellular levels of AIMP2-DX2 through selective degradation of the AIMP2-DX2 mRNA transcript.