Molecular plasticity of LAMA3 across the disease spectrum: pathogenic mechanisms and clinical translation

The laminin α3 chain, encoded by LAMA3, constitutes a principal component of laminin-332 (LN-332), an essential extracellular matrix (ECM) glycoprotein governing cell adhesion, proliferation, and tissue homeostasis. This systematic review consolidates current evidence on the molecular features and regulatory mechanisms of LAMA3, including its roles in PI3K/Akt, epithelial-mesenchymal transition (EMT), and Hippo-YAP signaling, as well as epigenetic and post-transcriptional modulation. Its context-dependent functions across distinct pathological states are delineated. In malignancies, including colorectal and ovarian cancers, LAMA3 functions as an oncogenic determinant that enhances invasion, metastatic dissemination, and chemotherapeutic resistance. In contrast, in hereditary diseases such as junctional epidermolysis bullosa (JEB) and chronic disorders such as idiopathic pulmonary fibrosis (IPF), LAMA3 deficiency or dysfunction constitutes a structural basis of tissue pathology. From a translational standpoint, elevated LAMA3 expression has been recognized as an independent prognostic indicator in pancreatic ductal adenocarcinoma, whereas LAMA3 promoter methylation is a candidate biomarker for platinum resistance in ovarian cancer. LAMA3-directed gene therapy for JEB has progressed to clinical evaluation. Current limitations in the field are critically examined, and emerging therapeutic approaches, including proteolysis-targeting chimeras (PROTACs), are discussed. Collectively, an integrated framework that connects LAMA3 biology with clinical applications is presented to inform future investigations and precision therapeutic strategies targeting this multifunctional molecule.