Understanding the molecular association between hyperkalemia and lung squamous cell carcinomas.

Background: Previous studies indicated a strong association between hyperkalemia and lung squamous cell carcinomas (LSCC). However, the underlying mechanism is not fully understood so far.

Methods: Literature-based data mining was conducted to identify genes, molecule, and cell processes linked to both hyperkalemia and LSCC. Pathway analysis was performed to explore the interactive network, common-target network, and common-regulator network for both disorders. Then, a mega-analysis using 11 independent LSCC RNA expression datasets (358 LSCCs and 278 healthy controls) was performed to test the hypothesis that genes influencing hyperkalemia may also play roles in LSCC.

Results: There was a significant overlap between the genes implicated with both diseases (20 genes, p-value = 4.98e-15), which counts for 16% of all hyperkalemia genes (125 genes). Network analysis identified 12 molecules as common targets for hyperkalemia and LSCC, and 19 molecules as common regulators. Moreover, 19 molecules were identified within an interactive network, through which hyperkalemia and LSCC could exert influence on each other. In addition, meta-analysis identified one hyperkalemia promoter, SPP1, as a novel contributor for LSCC (LFC = 2.64; p-value = 2.81e-6). MLR analysis suggests geographical region as an influential factor for the expression levels of SPP1 in LSCC patients (p value = 0.036, 0.054).

Conclusion: Our results showed that there was a common molecular basis for the pathology of both hyperkalemia and LSCC, and that genes promoting hyperkalemia might also play roles in the development of LSCC. However, this study did not suggest hypercalcemia as a casual factor for LSCC.