lncRNA TUG1通过miR-524-5p/BRAF轴调节甲状腺乳头状癌TPC-1细胞的增殖、凋亡和EMT进程

目的：lncRNA牛磺酸上调基因1(lncRNA TUG1)对甲状腺乳头状癌（PTC）细胞（TPC-1）增殖、凋亡和EMT进程的影响及作用机制。方法：qPCR检测人PTC组织（2019年5月至2021年4月期间在河北省唐山市工人医院手术切除的35例PTC组织及对应癌旁组织标本）与人PTC细胞TPC-1、BHP10-3、K1、SW-1736及人正常甲状腺上皮Nthyori 3-1细胞中lncRNA TUG1的表达。体外培养TPC-1细胞,将其分为对照组、si-NC组、si-TUG1组、miR-NC组、miR-524-5p mimic组、si-TUG1+NC inhibitor组、si-TUG1+miR-524-5p inhibitor组、miR-524-5p mimic+pcDNA组、miR-524-5p mimic+pcDNABRAF）组,对细胞进行si-TUG1、miR-524-5 pmimic、miR-524-5p inhibitor、pcDNA BRAF和各自相应的对照质粒转染,采用CCK-8法、FCM法分别检测TPC-1细胞增殖、凋亡情况;WB法检测TPC-1细胞中BRAF、P...     

ALKBH5-induced circular RNA NRIP1 promotes glycolysis in thyroid cancer cells by targeting PKM2

Although circular RNAs (circRNAs) are involved in cell proliferation, differentiation, apoptosis, and invasion, the underlying regulatory mechanisms of circRNAs in thyroid cancer have not been fully elucidated. This article aimed to study the role of circRNA regulated by N6-methyladenosine modification in papillary thyroid cancer (PTC). Quantitative real-time PCR, western blotting, and immunohistochemistry were used to investigate the expressions of circRNA nuclear receptor-interacting protein 1 (circNRIP1) in PTC tissues and adjacent noncancerous thyroid tissues. In vitro and in vivo assays were carried out to assess the effects of circNRIP1 on PTC glycolysis and growth. The N6-methyladenosine mechanisms of circNRIP1 were evaluated by methylated RNA immunoprecipitation sequencing, luciferase reporter gene, and RNA stability assays. Results showed that circNRIP1 levels were significantly upregulated in PTC tissues. Furthermore, elevated circNRIP1 levels in PTC patients were correlated with high tumor lymph node metastasis stage and larger tumor sizes. Functionally, circNRIP1 significantly promoted glycolysis, PTC cell proliferation in vitro, and tumorigenesis in vivo. Mechanistically, circNRIP1 acted as a sponge for microRNA (miR)-541-5p and miR-3064-5p and jointly upregulated pyruvate kinase M2 (PKM2) expression. Knockdown of m⁶A demethylase α-ketoglutarate-dependent dioxygenase alkB homolog 5 (ALKBH5) significantly enhanced circNRIP1 m⁶A modification and upregulated its expression. These results show that ALKBH5 knockdown upregulates circNRIP1, thus promoting glycolysis in PTC cells. Therefore, circNRIP1 can be a prognostic biomarker and therapeutic target for PTC by acting as a sponge for oncogenic miR-541-5p and miR-3064-5p to upregulate PKM2 expression.