Nokin, M.-J. | Search bioRxiv

bioRxiv2026

KDM6B interacts with nucleo-adhesome components CSRP2 and TGFB1I1 to regulate EMT

The methyltransferase EZH2 (Enhancer of Zest Homolog 2) and the demethylase KDM6B (Lysine Demethylase 6B) have been associated with epithelial to mesenchymal transition (EMT) and poor prognosis in various cancers. These enzymes methylate and demethylate H3K27me3 and regulate distinct sets of genes controlling EMT induction, despite having opposite catalytic activities. This could be due to their recruitment or the modulation of their activity by partner proteins on specific loci. This work sought to identify proteins associated with chromatin and interacting with EZH2 or with KDM6B during EMT. To do so, co-immunoprecipitation and mass spectroscopy was used under TGF{beta} (Tumor growth factor {beta}) and TNF (Tumor necrosis factor ) treatment to induce EMT in A549 lung cancer cells. Surprisingly, numerous proteins related to focal adhesions were identified to interact with EZH2 or KDM6B. These proteins are part of a nuclear protein interaction network previously described as nucleo-adhesome. Among these proteins, TGFB1I1 (transforming growth factor induced peptide 1) and CSRP2 (cysteine and glycine rich protein 2) were further confirmed to interact with KDM6B in the nucleus and even more so during EMT. The target genes of these complexes were then sought by knocking down KDM6B, TGFB1I1 or CSRP2. Three genes (coding Integrin alpha 5, Laminin y2 and Matrix Metalloproteinase 9) were confirmed to be regulated by KDM6B, TGFB1I1 and CSRP2. These findings may have clinical relevance, as immunohistochemistry analyses performed on a cohort of lung cancer patients revealed increased nuclear localization of TGFB1I1 and CSRP2 in cells undergoing EMT.

cell biology↗

bioRxiv2024

Targeted KRAS(G12V) degradation elicits efficient and durable lung adenocarcinoma regression in vivo

Recent drug discovery breakthroughs led to the approval of KRASG12C inhibitors in lung adenocarcinoma (LUAD). Unfortunately, clinical responses remain limited due to rapid resistance onset. Proteolysis-targeting chimeras (PROTACs) have emerged as promising alternatives to traditional inhibition. However, there is limited mechanistic understanding of KRAS degradation in vivo. Here, we developed a preclinical LUAD mouse model and demonstrated that targeted oncogenic KRAS degradation induces rapid tumor regression. Transcriptional, histological, and immunophenotypic analyses revealed a substantial remodeling of the tumor microenvironment. Notably, disease relapse observed during long-term degrader treatment stems from proteolysis machinery dysregulation, indicating resistance mechanisms distinct from those reported upon KRAS inhibition. Our findings highlight the therapeutic potential of KRAS degradation in LUAD, offering insights into cell-intrinsic and extrinsic mechanisms driving durable antitumor responses and supporting further clinical exploration. SIGNIFICANCEGiven the short duration of the clinical responses to KRAS inhibitors, complementary therapies are a dire medical need. Our preclinical findings endorse KRAS degradation as a therapeutic alternative in LUAD, where cell-intrinsic and extrinsic mechanisms drive tumor regression and durable therapeutic responses.

cancer biology↗