SLC34A2 inhibits tumorigenesis and progression via upregulating LRRK2/TTF-1/SELENBP1 axis in lung adenocarcinoma

Cancer Gene Ther. 2025 Jul 2. doi: 10.1038/s41417-025-00928-2. Online ahead of print.

ABSTRACT

Alveolar type II epithelial (AT2) cells have the properties of stem cells, abnormal AT2 cells serve as one of the original cells in lung adenocarcinoma (LUAD). However, the abnormal genes expression of AT2 cells during their malignant transformation into LUAD cells remain poorly understood. Importantly, SLC34A2 is a specific gene in AT2 cells of the lung. Our previous researches have reported that overexpression of SLC34A2 significantly inhibited proliferation, migration and invasion of LUAD cells. But, the underlying mechanisms of SLC34A2 in LUAD are largely unknown until now. Here, the present study discovered that the protein expression of Napi2b (SLC34A2), SELENBP1, TTF-1 and LRRK2 were all located in human AT2 cells of adjacent non-tumor tissues. However, the expression level of SLC34A2, SELENBP1, TTF-1 and LRRK2 were significantly decreased in LUAD tissues, and the expression of SLC34A2 was obviously positive correlation with the expression of SELENBP1, TTF-1 and LRRK2, respectively. Mechanistically, our study elucidated that overexpression of SLC34A2 could inhibit the activation of MEK/ERK signaling pathway through up-regulating the expression of LRRK2, and subsequently suppressed the expression of p-TTF-1(Ser327), which upregulated the expression of SELENBP1 by enhancing TTF-1 transcriptional activity. Ultimately, overexpression of SLC34A2 depressed the activation of PI3K/AKT/mTOR signaling pathway via up-regulating the expression of SELENBP1, which significantly inhibited the malignant characteristics of LUAD. In summary, our current research revealed a novel SLC34A2/LRRK2/TTF-1/SELENBP1 axis and its involvement in inhibiting the malignant characteristics of LUAD cells for the first time, which made contribution to further exploring the clinical application of SLC34A2. Furthermore, it also might offer novel insights into understanding how AT2 cells undergo malignant transformation into LUAD cells in the future.

PMID:40603644 | DOI:10.1038/s41417-025-00928-2