PROM2 upregulation promotes cancer cell migration and confers a poor prognosis in lung squamous cell carcinoma.

Lung squamous cell carcinoma (LUSC) remains a difficult-to-treat disease with a poor prognosis. While prominin-1 (PROM1/CD-133) is largely investigated in a variety of malignancies, the role of prominin-2 (PROM2), the other member of the prominin family, has not been studied in LUSC. Transcriptomic data derived from matched tumor and adjacent non-tumorous lung tissues of LUSC patients were employed to conduct an in-depth analysis of the genetic and epigenetic regulation of prominin genes within LUSC, utilizing bioinformatic approaches. Furthermore, cellular behavior experiments were executed to discern the biological functions of PROM2. It was observed that PROM2, in contrast to PROM1, exhibited significant upregulation and overexpression at both the mRNA and protein levels in LUSC, and this upregulation was correlated with shortened patient survival. Transcriptomic analysis unveiled DNA methylation as an epigenetic regulatory mechanism associated with PROM2 expression. Notably, two transcription factors, CBFB and NRIP1, were identified as potential regulators of PROM2 expression. Subsequent in vitro investigations demonstrated that knocking down PROM2 led to the inhibition of cancer cell migration and the epithelial-to-mesenchymal transition (EMT). In summary, the pronounced upregulation of PROM2 in LUSC patients was linked to an unfavorable prognosis, possibly attributable to its influence on cancer cell migration and EMT. These findings suggest that PROM2 could serve as a promising diagnostic biomarker and therapeutic target in the management of LUSC. Consequently, further research into the mechanistic aspects and potential therapeutic interventions targeting PROM2 is warranted in the clinical context.

Downregulated antisense lncRNA ENTPD3-AS1 contributes to the development of lung adenocarcinoma.

The poor outcome of patients with lung adenocarcinoma (LUAD) highlights the importance to identify novel effective prognostic markers and therapeutic targets. Long noncoding RNAs (lncRNAs) have generally been considered to serve important roles in tumorigenesis and the development of various types of cancer, including LUAD. Here, we aimed to investigate the role of ENTPD3-AS1 (ENTPD3 Antisense RNA 1) in LUAD and to explore its potential mechanisms by performing comprehensive bioinformatic analyses. The regulatory effect of ENTPD3-AS1 on the expression of NR3C1 was validated by siRNA-based silencing. The effect of miR-421 on the modulation of NR3C1 was determined by miRNA mimics and inhibitors transfection. ENTPD3-AS1 was expressed at lower levels in tumor parts and negatively correlated with unfavorable prognosis in LUAD patients. It exerted functions as a tumor suppressor gene by competitively binding to oncomir, miR-421, thereby attenuating NR3C1 expression. Transfection of lung cancer A549 cells with miR-421 mimics decreased the expression of NR3C1. Transfection of lung cancer A549 cells with miR-421 inhibitors increased the expression of NR3C1 with lower cellular functions as proliferation and migration via epithelial-mesenchymal transition. In addition, inhibition of ENTPD3-AS1 by siRNA transfection decreased the levels of NR3C1, supporting the ENTPD3-AS1/miR-421/NR3C1 cascade. Moreover, the bioinformatic analysis also showed that ENTPD3-AS1 could interact with the RNA-binding proteins (RBPs), CELF2 and QKI, consequently regulating RNA expression and processing. Taken together, we identified that ENTPD3-AS1 and its indirect target NR3C1 can act as novel biomarkers for determining the prognosis of patients with LUAD, and further study is required.

Characterization of the pleural microenvironment niche and cancer transition using single-cell RNA sequencing in EGFR-mutated lung cancer.

Background: Lung cancer is associated with a high mortality rate and often complicated with malignant pleural effusion (MPE), which has a very poor clinical outcome with a short life expectancy. However, our understanding of cell-specific mechanisms underlying the pathobiology of pleural metastasis remains incomplete. Methods: We analyzed single-cell transcriptomes of cells in pleural effusion collected from patients with lung cancer and congestive heart failure (as a control), respectively. Soluble and complement factors were measured using a multiplex cytokine bead assay. The role of ferroptosis was evaluated by GPX4 small interfering RNA (siRNA) transfection and overexpression. Results: We found that the mesothelial-mesenchymal transition (MesoMT) of the pleural mesothelial cells contributed to pleural metastasis, which was validated by lung cancer/mesothelial cell co-culture experiments. The ferroptosis resistance that protected cancer from death which was secondary to extracellular matrix detachment was critical for pleural metastasis. We found a universal presence of immune-suppressive lipid-associated tumor-associated macrophages (LA-TAMs) with complement cascade alteration in the MPE of the lung cancer patients. Specifically, upregulated complement factors were also found in the MPE, and C5 was associated with poor overall survival in the lung cancer patients with epidermal growth factor receptor mutation. Plasmacytoid dendritic cells (pDCs) exhibited a dysfunctional phenotype and pro-tumorigenic feature in the primary cancer. High expression of the gene set extracted from pDCs was associated with a poor prognosis in the lung cancer patients. Receptor-ligand interaction analysis revealed that the pleural metastatic niche was aggravated by cross-talk between mesothelial cells-cancer cells/immune cells via TNC and ICAM1. Conclusions: Taken together, our results highlight cell-specific mechanisms involved in the pathobiological development of pleural metastasis in lung cancer. These results provide a large-scale and high-dimensional characterization of the pleural microenvironment and offer a useful resource for the future development of therapeutic drugs in lung cancer.

EMP2 induces cytostasis and apoptosis via the TGFß/SMAD/SP1 axis and recruitment of P2RX7 in urinary bladder urothelial carcinoma.

PURPOSE: Urinary bladder urothelial carcinoma (UBUC) is a common malignant disease, and its high recurrence rates impose a heavy clinical burden. The objective of this study was to identify signaling pathways downstream of epithelial membrane protein 2 (EMP2), which induces cytostasis and apoptosis in UBUC. METHODS: A series of in vitro and in vivo assays using different UBUC-derived cell lines and mouse xenograft models were performed, respectively. In addition, primary UBUC specimens were evaluated by immunohistochemistry. RESULTS: Exogenous expression of EMP2 in J82 UBUC cells significantly decreased DNA replication and altered the expression levels of several TGFß signaling-related proteins. EMP2 knockdown in BFTC905 UBUC cells resulted in opposite effects. EMP2-dysregulated cell cycle progression was found to be mediated by the TGFß/TGFBR1/SP1 family member SMAD. EMP2 or purinergic receptor P2X7 (P2RX7) gene expression upregulation induced apoptosis via both intrinsic and extrinsic pathways. In 242 UBUC patient samples, P2RX7 protein levels were found to be significantly and positively correlated with EMP2 protein levels. Low P2RX7 levels conferred poor disease-specific and metastasis-free survival rates, and significantly decreased apoptotic cell rates. EMP2 was found to physically interact with P2RX7. In the presence of a P2RX7 agonist, BzATP, overexpression of both EMP2 and P2RX7 significantly increased apoptotic cell rates compared to overexpression of EMP2 or P2RX7 alone. CONCLUSIONS: EMP2 induces cytostasis via the TGFß/SMAD/SP1 axis and recruits P2RX7 to enhance apoptosis in UBUC. Our data provide new insights that may be employed for the design of UBUC targeting therapies.