Abstract
EGFR-mutated lung cancer patients sometimes display restricted responses to third-generation tyrosine kinase inhibitors (TKIs), potentially attributable to undervalued input from stromal cells, notably pericytes (PCs). The study shows that PCs isolated from EGFR-mutated patients have a unique secretome profile, notably secreting IL32 and affecting signaling pathways and biological processes linked to TKI sensitivity. Clinical evidence, supported by single-cell RNA sequencing and multiplex immunostaining of tumor tissues, confirms the presence of IL32-expressing pericytes closely interacting with β5-integrin-expressing cancer cells in EGFR-mutated patients, impacting therapeutic response and prognosis. Co-culture and conditioned medium experiments demonstrate that PCs reduce TKI effectiveness in EGFR-mutated cancer cells, a reversible phenomenon through silencing IL32 expression in PCs or depleting the IL32 receptor β5-integrin on cancer cells, thereby restoring cancer cell sensitivity. Mechanistically, it is shown that YY1 signaling upregulates IL32 secretion in PCs, subsequently activating the β5-integrin-Src-Akt pathway in EGFR-mutated cancer cells, contributing to their TKI sensitivity. In animal studies, co-injection of cancer cells with PCs compromises TKI effectiveness, independently of blood vessel functions, while inhibition of β5-integrin restores tumor cell sensitivity. Overall, the findings highlight direct crosstalk between cancer cells and pericytes, impacting TKI sensitivity via IL32-β5-integrin paracrine signaling, proposing an enhanced therapeutic approach for EGFR-mutated patients.