Background: Inherited susceptibility and environmental carcinogens are crucial players in lung cancer etiology, and both exhibit population heterogeneity. MUC16 is overexpressed in various cancers and often associated with poor prognosis. Present work was to investigate the clinical significance of MUC16 in non-small cell lung cancer patients affected by familial lung cancer (FLC) and indoor air pollution caused by coal use. Methods: Clinicopathologic characteristics and MUC16 expression were analyzed and evaluated in our subject population. Vectors were constructed for MUC16 gene knockout and overexpression, then we examined how MUC16 affected lung cancer cell behaviors, including proliferation, migration, invasion and chemoresistance. Results: FLC showed significant association with early-onset (P<0.01) and later stage (P<0.01). Indoor air pollution was associated with younger age (P<0.01), later stage (P<0.05) and AD histology type (P<0.05). Interestingly, two age peaks were observed in our FLC and sporadic group respectively, possibly suggesting multiple major contributors to lung cancer in our subject population. MUC16 overexpression was significantly associated with FLC (P<0.05), indoor air pollution (P<0.01) and later stage (P<0.01), additionally more metastasis cases were observed in patients with up-regulated MUC16 (18.1% vs. 10.3%). Taken together, elevated MUC16 may potentially be one molecular character of FLC in local residents. Intriguingly, patients with more MUC16 up-regulation seemed to have a lower number of white blood cells, especially neutrophils, this reflected MUC16's role in immune regulation. In cell behavior experiments, high MUC16 level could contribute to lung cancer cell proliferation, migration, invasion and chemoresistance, but there were variations among cell lines. Conclusions: MUC16 plays crucial roles in lung cancer pathogenesis, progression and chemoresistance. Interestingly, its association with FLC and indoor air pollution highlights the complexity of lung cancer etiology. Our findings provide useful information to study the intricate interaction between environmental carcinogens and population genetic background.

Department of Neurosurgery the 3rd Affiliated Hospital of Kunming Medical University Kunming 650106 China

Department of Radiology the 3rd Affiliated Hospital of Kunming Medical University Kunming 650106 China

Department of Thoracic Surgery 1 the 3rd Affiliated Hospital of Kunming Medical University Kunming 650106 China

The Key Laboratory of Lung Cancer Research the 3rd Affiliated Hospital of Kunming Medical University Kunming 650106 China

The Laboratory of Cancer Cell Biology Institute of Molecular Genetics ASCR Videnska Prague Czech Republic