Anti-GPX2 polyclonal antibody

Lung cancer is the leading cause of cancer death worldwide, with poor prognosis and a high rate of recurrence despite early surgical removal. Hypoxic regions within tumors represent sources of aggressiveness and resistance to therapy. Although long non-coding RNAs (lncRNAs) are increasingly recognized as major gene expression regulators, their regulation and function following hypoxic stress are still largely unexplored. Combining profiling studies on early-stage lung adenocarcinoma (LUAD) biopsies and on A549 LUAD cell lines cultured in normoxic or hypoxic conditions, we identified a subset of lncRNAs that are both correlated with the hypoxic status of tumors and regulated by hypoxia in vitro. We focused on a new transcript, NLUCAT1, which is strongly upregulated by hypoxia in vitro and correlated with hypoxic markers and poor prognosis in LUADs. Full molecular characterization showed that NLUCAT1 is a large nuclear transcript composed of six exons and mainly regulated by NF-kappa B and NRF2 transcription factors. CRISPR-Cas9-mediated invalidation of NLUCAT1 revealed a decrease in proliferative and invasive properties, an increase in oxidative stress and a higher sensitivity to cisplatin-induced apoptosis. Transcriptome analysis of NLUCAT1-deficient cells showed repressed genes within the antioxidant and/or cisplatin-response networks. We demonstrated that the concomitant knockdown of four of these genes products, GPX2, GLRX, ALDH3A1, and PDK4, significantly increased ROS-dependent caspase activation, thus partially mimicking the consequences of NLUCAT1 inactivation in LUAD cells. Overall, we demonstrate that NLUCAT1 contributes to an aggressive phenotype in early-stage hypoxic tumors, suggesting it may represent a new potential therapeutic target in LUADs.

NKX3.1 is a prostate-specific transcription factor that is regulated by the androgen receptor in the presence of androgens. It functions as a tumor suppressor against the development of prostatic intraepithelial neoplasia and primary prostate tumors. Here, a recognized approach combining in silico analysis and chromatin immunoprecipitation (ChIP) was used to identify the genes directly regulated by NKX3.1 promoter binding in LNCaP cells. Quantitative PCR using ChIP-captured DNAs as templates verified a subset of NKX3.1 binding motifs. Thus, in the presence of androgens, significant NKX3.1 binding occurs to promoters of GPX2, QSCN6, SOD1, and SOD2 genes that contribute to oxidative stress regulation. Our data demonstrate that NKX3.1 is found in a DNA-bound state transiently at a basal level even in the absence of androgens; an increase in androgens promotes NKX3.1 binding, perhaps temporally rather than spatially, to the specific sites. The overall changes potentiate the transcriptional regulatory activity of NKX3.1, although they are dependent on the androgen receptor for the target promoters. The results suggest that NKX3.1 contributes to an antioxidant response by regulating the transcription of oxidative stress regulators by direct promoter binding.