Zinc finger protein 263 upregulates interleukin 33 and suppresses autophagy to accelerate the malignant progression of non-small cell lung cancer.

PURPOSE: Non-small cell lung cancer (NSCLC) is a complex disease that remains a major public health concern worldwide. One promising avenue for NSCLC treatment is the targeting of transcription factors that regulate key pathways involved in cancer progression. In this study, we investigated the role of the transcription factor ZNF263 in NSCLC and its impact on the regulation of IL33, apoptosis, and autophagy. METHODS: Levels of ZNF263 in tissues and cell lines were identified, after which the effects of its knockdown on cellular malignant behaviors, apoptosis and autophagy were assessed. Based on bioinformatics analysis, ZNF263 was found to bind to IL33 promoter, their mutual relationship was confirmed, as well as the role of IL33 in the regulation of ZNF263. The involvement of ZNF263 in the growth of xenograft tumors was assessed using tumor-bearing nude mouse models. RESULTS: Experimental results revealed that ZNF263 was upregulated in NSCLC tissue samples and cell lines. Its expression level is positively correlated with cellular malignant behaviors. We further demonstrated that ZNF263 upregulated IL33 expression, which, in turn, promoted the proliferation and migration, inhibited apoptosis and autophagy in NSCLC cells. Furthermore, ZNF263 knockdown reduced the growth of xenograft tumors in nude mice. CONCLUSION: This finding suggests that the inhibition of ZNF263 or IL33 may represent a novel therapeutic strategy for NSCLC. Importantly, our results highlight the crucial role of transcription factors in NSCLC and their potential as therapeutic targets.

LncRNA NBR2 Regulates Cancer Cell Stemness and Predicts Survival in Non-small Cell Cancer Patients by Downregulating TGF-ß1.

BACKGROUND: LncRNA NBR2 is a key regulator in cancer metabolism. However, its role in lung cancer is unknown. OBJECTIVE: This study aimed to explore the function of NBR2 in non-small cell lung cancer (NSCLC), which is the most common type of lung cancer. METHODS: Paired NSCLC and non-cancer tissues were collected from 68 patients with NSCLC. The expression of NBR2 and transforming growth factor-ß1 (TGF-ß1) in these samples was analyzed by RT-qPCR. The prognostic value of NBR2 for NSCLC was explored by performing a 5-year follow-up study. The interaction between NBR2 and TGF-ß1 in two NSCLC cell lines was detected by overexpression assay, followed by RT-qPCR and Western blot analysis. Flow cytometry was performed to evaluate the role of NBR2 and TGF-ß1 in regulating NSCLC cell stemness. RESULTS: NBR2 was significantly downregulated in NSCLC tissues than that in non-cancer tissues of NSCLC patients, and low expression levels of NBR2 predicted poor survival. TGF-ß1 was significantly upregulated in NSCLC tissues than that in non-cancer tissues, and was inversely correlated with NBR2. Overexpression of NBR2 downregulated TGF-ß1, while overexpression of TGF-ß1 did not affect the expression of NBR2. Overexpression of NBR2 inhibited, while overexpression of TGF-ß1 promoted NSCLC cell stemness. Overexpression of TGF-ß1 attenuated the effects of overexpression of NBR2. Mechanically, NBR2 interacted with Notch1 protein to inhibit its expression, thereby inhibiting the expression of TGF-ß1 and further affecting the proportion of CD133+ cells. CONCLUSION: LncRNA NBR2 regulates cancer cell stemness and predicts survival in NSCLC possibly by downregulating TGF-ß1 through Notch1.

FAM201A knockdown inhibits proliferation and invasion of lung adenocarcinoma cells by regulating miR-7515/GLO1 axis.

Lung adenocarcinoma (LUAD) is the most important histological type of lung cancer. We aimed to identify the role of long noncoding RNA family with sequence similarity 201-member A (FAM201A) in the occurrence and development of LUAD. The expressions of FAM201A in LUAD tissues and cells were determined via reverse transcription-quantitative polymerase chain reaction. The effects of FAM201A knockdown on LUAD cell malignant phenotypes were examined by cell counting kit-8, 5-ethynyl-2'-deoxyuridine, flow cytometry, transwell assay and wound healing assay. The underlying mechanism by which FAM201A regulated LUAD progression was also studied. Nude mice LUAD xenograft model was constructed, to explore the in vivo effect of FAM201A. Our results showed that the FAM201A expression in LUAD tissues and cell lines was notably higher than normal tissues and cells. Downregulation of FAM201A suppressed the cell proliferation, migration and invasion and promoted the cell apoptosis in LUAD cells. While, FAM201A overexpression showed tumorigenesis effect on LUAD cells. Moreover, we demonstrated that FAM201A affected LUAD progression via targeting miR-7515 to promote GLO1 expression. FAM201A downregulation also suppressed LUAD development in vivo experiment. Our results indicated that FAM201A was an oncogene in LUAD and might be a novel therapeutic target for LUAD.

A positive feedback loop formed by NGFR and FOXP3 contributes to the resistance of non-small cell lung cancer to icotinib.

BACKGROUND: The study was aimed to investigate the mechanisms causing acquired chemoresistance to icotinib, an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), in non-small cell lung cancer (NSCLC). METHODS: Three wildtype NSCLC cell lines were used to produce icotinib-resistant (IR) cell lines. Real-time PCR and western blot assays were used to detect the mRNA and protein levels of nerve growth factor receptor (NGFR) and forkhead box P3 (FOXP3). MTT assay was used to detect the viability of cells. Luciferase activity and chromatin immunoprecipitation (ChIP) assays were used to detect the transactivation activity of FOXP3. RESULTS: NGFR and FOXP3 were dramatically increased in three IR NSCLC cell lines, and both proteins were required for induction of icotinib resistance. NGFR-induced icotinib resistance was partially related to activation of AKT, a well-known chemoresistance inducer in many tumor types. Activated AKT could induce the expression of FOXP3 which further induce icotinib through transactivating NGFR expression by binding to its promoter. In addition, the inducing of FOXP3 could also induce icotinib resistance solely. CONCLUSIONS: NGFR, AKT and FOXP3 form a positive feedback loop, by which the abilities of NGFR and FOXP3 on inducing icotinib resistance are further enhanced. We believe that NGFR and FOXP3 might be novel therapeutic targets in NSCLC.

Downregulation of fibroblast growth factor 5 inhibits cell growth and invasion of human nonsmall-cell lung cancer cells.

The morbidity and mortality rates of nonsmall-cell lung cancer (NSCLC) have increased in recent years. We aimed to explore the biological role of fibroblast growth factor 5 (FGF5) in NSCLC. We first established that the expression of FGF5 was increased in NSCLC tissues compared with the normal adjacent tissues. The expression of FGF5 was also increased in NSCLC cell lines. The effect of FGF5 silencing on cell proliferation, cell cycle, apoptosis, migration, and invasion of H661 and CALU1 cells was then examined. Downregulation of FGF5 significantly inhibited cell proliferation and induced G1 phase cell cycle arrest compared with the negative control small interfering (siNC) groups. Cell apoptosis was promoted by siFGF5 treatment. Cell migration and invasion of H661 and CALU1 cells with siFGF5 transfection were markedly diminished compared with the siNC groups. In addition, migration and invasion-associated proteins (E-cadherin, matrix metalloproteinase-2 [MMP-2], and MMP-9) and epithelial mesenchymal transition markers (N-cadherin, vimentin, snail, and slug) were also regulated by FGF5 siRNA treatment. Gene set enrichment analysis on The Cancer Genome Atlas dataset showed that the Kyoto Encyclopedia of Genes and Genomes (KEGG) cell cycle and vascular endothelial growth factor (VEGF) pathways were correlated with FGF5 expression, which was further confirmed in NSCLC cells by Western blot analysis. Our results indicated that FGF5 silencing suppressed cell growth and invasion via regulation of the cell cycle and VEGF pathways. Therefore, FGF5 may serve as a promising therapeutic strategy for NSCLC.

IL­33/ST2 pathway in a bleomycin­induced pulmonary fibrosis model.

The present study aimed to investigate the interleukin (IL)­33/ST2 pathway in a model of acute pulmonary fibrosis, and to examine the pathogenesis of pulmonary fibrosis. The pulmonary fibrosis model was established by a single exposure to bleomycin (BLM group) endotracheally to represent idiopathic pulmonary fibrosis, and a control (Cont) group was treated with the same volume of saline. The degrees of acute injury, inflammation and fibrosis were detected using hematoxylin and eosin and Masson's staining. The IL­33, ST2, myeloid differentiation primary response 88 (MyD88) and tumor necrosis factor receptor­associated factor 6 (TRAF6) proteins were detected using Western blotting. The serum levels of IL­4 and IL­13 were detected using an enzyme­linked immunosorbent assay. The results indicated that, compared with the Cont group, there were significant differences in the alveolitis scores in the BLM group on days 3, 7, 14 and 28 (P<0.01). The grades of fibrosis were also significantly different on days 7, 14 and 28 (P<0.01). On examining the dynamic protein expression levels of IL­33, ST2, MyD88 and TRAF6, the expression of IL­33 in the BLM group increased initially, and then decreased gradually following a peak on day 7. The significant differences between the BLM and Cont groups were observed on days 3 and 7 (P<0.05). Compared with the Cont group, the protein levels of ST2, MyD88 and TRAF6 in the BLM group exhibited an increasing trend from day 3, with significant differences, compared with the Cont group, on days 3, 7, 14 and 28 (P<0.05). On examination of the serum levels of IL­4 and IL­13 in each group, the levels of IL­4 and IL­13 in BLM group remained higher from day 7, with peaks on day 28, and were significantly different, compared with the Cont group, on days 7, 14 and 28 (P<0.05). In conclusion, the IL­33/ST2 signaling pathway was found to be involved in the rodent model of pulmonary fibrosis induced by bleomycin.