Long intergenic non-protein coding RNA 626 (LINC00626)

Long intergenic non-protein coding RNA 626 (LINC00626) is a cytoplasm-localized lncRNA encoded on human chromosome 1q24.2. It consists of three exons and two introns and is transcriptionally regulated by estrogen receptor alpha (ERα). LINC00626 is markedly upregulated in breast cancer, especially in ERα-positive and tamoxifen-resistant tumors. Functionally, LINC00626 promotes cell proliferation and suppresses apoptosis by directly interacting with UPF1 and sustaining elevated UPF1 levels in tumor cells. Targeting LINC00626 by shRNA restores tamoxifen sensitivity in resistant cells, likely via activation of the PERK-ATF4-CHOP pathway mediated through UPF1 modulation. Thus, LINC00626 is a critical modulator of drug resistance and tumor growth in hormone-dependent breast cancer, with both mechanistic and biomarker relevance.

Other names

MGC4473LINC00626Long intergenic non-coding RNA 626

Drugs such as tamoxifen act by interfering with estrogen signaling; LINC00626 disrupts tamoxifen efficacy by upregulating UPF1, thus sustaining resistance. Targeting LINC00626 (e.g., with shRNA) restores tamoxifen sensitivity, likely via activation of the PERK-ATF4-CHOP signaling pathway in the presence of decreased UPF1.