Distinct cancer-promoting stromal gene expression depending on lung function. Homo sapiens

Chronic obstructive pulmonary disease (COPD) is an independent risk factor for lung cancer, but the underlying molecular mechanisms are unknown. We hypothesized that lung stromal cells activate pathological gene expression programs supporting oncogenesis. To identify molecular mechanisms operating in the lung stroma that support development of lung cancer. Study subjects included patients with- or without- lung cancer across a spectrum of lung function. We conducted multi-omics analysis of non-malignant lung tissue to quantify the transcriptome, translatome and proteome. Cancer-associated gene expression changes predominantly manifested as alterations in the efficiency of mRNA translation modulating protein levels in the absence of corresponding changes in mRNA levels. The molecular mechanisms driving these cancer-associated translation programs differed based on lung function. In subjects with normal to mildly impaired lung-function, the mammalian target of rapamycin (mTOR) pathway served as an upstream driver; whereas in severe airflow obstruction, pathways downstream of pathological extracellular matrix (ECM) emerged. Consistent with a role during cancer initiation, both the mTOR and ECM gene expression programs paralleled activation of previously identified pro-cancer secretomes. Furthermore, in situ examination of lung tissue documented that stromal fibroblasts express cancer-associated proteins from the two pro-cancer secretomes including IL6 in mild or no airflow obstruction and BMP1 in severe airflow obstruction. Two distinct stromal gene expression programs promoting cancer initiation are activated in lung cancer patients depending on lung function. Our work has implications both for screening strategies and personalized approaches to cancer treatment. Overall design: Polysome-profiling of non-cancerous lung stroma tissue samples from patients with or without lung cancer across a range of forced expiratory volume in one second (FEV1)