Autophagy-associated circRNA circCDYL augments autophagy and promotes breast cancer progression

Abstract

Background: Although both circular RNAs (circRNAs) and autophagy are associated with the function of breast cancer (BC), whether circRNAs regulate BC progression via autophagy remains unknown. In this study, we aim to explore the regulatory mechanisms and the clinical significance of autophagy-associated circRNAs in BC. Methods: Autophagy associated circRNAs were screened by circRNAs deep sequencing and validated by qRT-PCR in BC tissues with high-and low-autophagic level. The biological function of autophagy associated circRNAs were assessed by plate colony formation, cell viability, transwells, flow cytometry and orthotopic animal models. For mechanistic study, RNA immunoprecipitation, circRNAs pull-down, Dual luciferase report assay, Western Blot, Immunofluorescence and Immunohistochemical staining were performed. Results: An autophagy associated circRNA circCDYL was elevated by 3.2 folds in BC tissues as compared with the adjacent non-cancerous tissues, and circCDYL promoted autophagic level in BC cells via the miR-1275-ATG7/ULK1 axis; Moreover, circCDYL enhanced the malignant progression of BC cells in vitro and in vivo. Clinically, increased circCDYL in the tumor tissues and serum of BC patients was associated with higher tumor burden, shorter survival and poorer clinical response to therapy. Conclusions: circCDYL promotes BC progression via the miR-1275-ATG7/ULK1-autophagic axis and circCDYL could act as a potential prognostic and predictive molecule for breast cancer patients.

Broad-Spectrum Preclinical Antitumor Activity of Chrysin: Current Trends and Future Perspectives

“…Autophagy is another programmed cell death that is activated by chrysin in cancer therapy. As autophagy has a dual role in cancer, meaning it may suppress cancer progression, or may function as a pro-survival factor in promoting the proliferation of cancer cells [ 330 , 331 , 332 , 333 ], much attention should be directed towards the regulation of autophagy by chrysin in cancer therapy. It has been reported that chrysin induces autophagy in cancer therapy, showing the anti-tumor role of autophagy.…”

Knockdown of hsa_circ_0074298 suppressed the progression of pancreatic cancer by targeting the miR-519/SMOC2 axis

“…We utilized TRIzol reagent (Invitrogen Life Technologies) to separate total RNA from cultured PC cells and tissues as previous research described [16]. The RNA concentrations were measured with a NanoDrop 2000 Spectrophotometer (Nano Drop Technologies, Wilmington, DE, U.S.A.) and 500 ng total RNA or miRNA was reverse transcribed into cDNA using the High Capacity RNA to cDNA Kit (Takara Biotechnology Co., Ltd., Dalian, China) or the microRNA Reverse Transcription kit (Takara Biotechnology Co., Ltd.).…”

Overexpression of circRNA circUCK2 Attenuates Cell Apoptosis in Cerebral Ischemia-Reperfusion Injury via miR-125b-5p/GDF11 Signaling

“…Circular RNAs (circRNAs), which are newly identified endogenous non-coding RNAs (ncRNAs), are characterized by back-splicing resulting from covalently closed continuous loops. 11 , 12 circRNAs play a role in several diseases, including stroke, cancer development, and heart disease. 11 , 13 For instance, circHIPK3 regulates cell proliferation and migration by sponging miR-124 and regulating Aquaporin 3 (AQP3) expression in hepatocellular carcinoma.…”

“… 11 , 12 circRNAs play a role in several diseases, including stroke, cancer development, and heart disease. 11 , 13 For instance, circHIPK3 regulates cell proliferation and migration by sponging miR-124 and regulating Aquaporin 3 (AQP3) expression in hepatocellular carcinoma. 14 , 15 circRNA_001569 promotes cell proliferation through absorbing miR-145 in gastric cancer.…”