lncRNA CASC2 Enhances 131I Sensitivity in Papillary Thyroid Cancer by Sponging miR-155

Abstract

Long noncoding RNA cancer susceptibility candidate 2 (CASC2) has been reported to play an anticancer role in papillary thyroid cancer (PTC). Radioiodine (131I) is a common option for the treatment of PTC. However, the role and mechanism of CASC2 in 131I sensitivity remain unclear. In this study, 131I-resistant cells were constructed through continuous treatment of 131I. The expression levels of CASC2 and miR-155 were measured by qRT-PCR. The IC50 of 131I was analyzed by cell viability using MTT assay. Flow cytometry was conducted to determine cell apoptosis induced by 131I. The association between CASC2 and miR-155 was evaluated by luciferase assay and RNA immunoprecipitation. A mouse xenograft model was built to explore the effect of CASC2 on the growth of 131I-resistant PTC cells in vivo. Results showed that CASC2 expression was decreased in PTC tissues and cells, and low expression of CASC2 was associated with poor outcome of patients. CASC2 level was reduced in 131I-resistant cells. Knockdown of CASC2 inhibited 131I sensitivity in thyroid cancer cells. Overexpression of CASC2 enhanced 131I sensitivity in constructed resistant PTC cells. CASC2 was a decoy of miR-155, and CASC2-mediated promotion of 131I sensitivity was weakened by decreasing miR-155. Abundance of CASC2 inhibited the growth of 131I-resistant cells in vivo. As a conclusion, CASC2 increases 131I sensitivity in PTC by sponging miR-155, providing a novel target for the treatment of thyroid cancer patients with 131I resistance.

C10orf55, CASC2, and SFTA1P lncRNAs Are Potential Biomarkers to Assess Radiation Therapy Response in Head and Neck Cancers

“…The primers for quantification of C10orf55, C3orf35, C5orf38, CASC2, MEG3, MYCNOS, SFTA1P, SNHG3, and TMEM105 were described previously [ 28 , 29 , 30 , 31 , 32 , 33 , 34 ] and are presented in Table 1 . The compatibility of all primers and their complementarity to the target sequence was checked using the Basic Local Alignment Search Tool (BLAST), National Center for Biotechnology Information (NCBI), Bethesda, Maryland, United States of America, available at: , accessed on 15 May 2022.…”

The functions of long noncoding RNAs on regulation of F-box proteins in tumorigenesis and progression

“…One group showed that CASC2 overexpression exhibited antitumor activities through sponging miR-24-3p in thyroid cancer ( 109 ). Another group reported that CASC2 increased radiotherapy sensitivity via sponging miR-155 in papillary thyroid cancer ( 112 ). Similarly, lncRNA CASC2 increased irradiation-triggered endoplasmic reticulum stress via regulation of PERK signaling pathway in NSCLC cells ( 113 ).…”

The lncRNA CASC2 Modulates Hepatocellular Carcinoma Cell Sensitivity and Resistance to TRAIL Through Apoptotic and Non-Apoptotic Signaling

“…LncRNA CASC2, located at chromosome 10q26, was first identified to be dysregulated in endometrial carcinoma ( 27 ). CASC2, as a tumor suppressor, was subsequently discovered to play a crucial part in multiple tumor diseases, including pancreatic cancer ( 28 ), papillary thyroid cancer ( 29 ), cholangiocarcinoma ( 30 ), glioma ( 31 ), and so on. Given the critical role of the NF-κB pathway in HCC resistance to TRAIL, identifying more lncRNA CASC2/miRNA axes modulating the NF-κB pathway in HCC cells might provide novel targets for restoring TRAIL sensitivity.…”