Altered androgen-receptor (AR) expression and/or constitutively active AR are commonly associated with prostate cancer (PCa) progression. Targeting AR remains a focal point for designing new strategy of PCa therapy. Here, we have shown that DAB2IP, a novel tumor suppressor in PCa, can inhibit AR-mediated cell growth and gene activation in PCa cells via distinct mechanisms. DAB2IP inhibits the genomic pathway by preventing AR nuclear translocation or phosphorylation and suppresses the non-genomic pathway via its unique functional domain to inactivate c-Src. Also, DAB2IP is capable of suppressing AR activation in an androgen-independent manner. In addition, DAB2IP can inhibit several AR splice variants showing constitutive activity in PCa cells. In DAB2IP(-/-) mice, the prostate gland exhibits hyperplastic epithelia, in which AR becomes more active. Consistently, DAB2IP expression inversely correlates with AR activation status particularly in recurrent or metastatic PCa patients. Taken together, DAB2IP is a unique intrinsic AR modulator in normal cells, and likely can be further developed into a therapeutic agent for PCa.

Papillary thyroid carcinoma (PTC) is an aggressive histological subtype of thyroid carcinoma (THCA), whose occurrence rate is high. The participation of long noncoding RNAs in the pathologies of cancers has attracted significant attention during the past decades. The purpose of the current study is to investigate the role of NR2F1 antisense RNA 1 (NR2F1‐AS1) in PTC. The expression of NR2F1 in THCA samples was analyzed by bioinformatics tool gene expression profiling interactive analysis. Levels of NR2F1‐AS1, microRNA‐423‐5p (miR‐423‐5p), and SRY‐box 12 (SOX12) were evaluated by a quantitative reverse transcription‐polymerase chain reaction and Western blot. The impact of NR2F1‐AS1 on PTC cell proliferation and invasion was assessed by Cell Counting Kit‐8, EdU, and Transwell invasion assays. The interactions among NR2F1‐AS1, miR‐423‐5p, and SOX12 were determined by RNA immunoprecipitation and luciferase reporter assays. Consequently, we found that NR2F1‐AS1 and SOX12 levels were elevated in PTC, whereas miR‐423‐5p was downregulated in PTC cells. Functionally, NR2F1‐AS1 silence led to reduced proliferation and invasion of PTC cells. Mechanistically, NR2F1‐AS1 interacted with miR‐423‐5p to induce SOX12 expression in PTC cells. In conclusion, the present study firstly stated that NR2F1‐AS1 regulated miR‐423‐5p/SOX12 to promote proliferation and invasion of PTC, indicating NR2F1‐AS1 as a potential novel target for the molecular‐targeted therapy of PTC.

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This study aimed to investigate the effects of microRNA (miR)-22 on biological behaviors of colon cancer cells and to explore the relationship between miR-22 and NLRP3. Materials and Methods: First, human colon cancer HCT116 cells were transfected with a miR-22 mimic, miR-22 inhibitor, control mimic, and control inhibitor, respectively. CCK8, colony formation, and transwell assays were performed to observe cell proliferation, migration, and invasion. Western blotting was used to analyze the expression of recombinant NLRP3 (NLR family, pyrin domain-containing protein 3) and epithelial-mesenchymal transformation (EMT)-related proteins. The target relationship between miR-22 and NLRP3 was verified by double luciferase report. Second, an NLRP3 inhibitor and NLRP3 mimic were transfected into HCT116 cells, and the biological behaviors and EMT-related proteins were again observed. Finally, a nude mouse xenograft model was constructed to verify the above results. Results: In vitro, compared with the control group, administration of the miR-22 mimic significantly decreased proliferation, migration, and invasion of HCT116 cells, whereas the miR-22 inhibitor markedly increased their proliferation and invasion (p<0.05). Levels of NLRP3, interleukin-1β (IL-1β), matrix metalloproteinase-9 (MMP-9), MMP-2, N-cadherin, and vimentin were significantly reduced after miR-22 mimic transfection (p<0.05). Furthermore, silencing of NLRP3, a downstream gene of miR-22 in HCT116 cells, suppressed proliferation, migration, and invasion of HCT116 cells. However, overexpression of NLRP3 weakened the effects of the miR-22 mimic. In vivo, overexpression of miR-22 slowed the growth rate of tumors and reduced Ki-67 expression in tumor tissues compared with the model group (p<0.05). In tumor tissues, overexpression of miR-22 also decreased expression of NLRP3, IL-1β, MMP-9, MMP-2, N-cadherin, and vimentin compared with the model group (p<0.05). Overexpression of NLRP3 weakened the role of miR-22 overexpression in vivo. Conclusion: miR-22 suppresses cell proliferation, migration, and invasion in colorectal cancer by targeting NLRP3.