ERBB2 and breast cancer: Subsequently, qRT‒PCR was used to evaluate the expression levels of the filtered circRNAs, and we found that circ-TRIO was significantly upregulated in the TNBC cell lines and positively correlated with the degree of malignancy of breast cancer cells (Fig. 1D); additionally, circ-TRIO was specifically upregulated in the TNBC tissues compared with tissues of the other subtypes (luminal A, luminal B and HER2 enriched) (Fig. 1E), suggesting that circ-TRIO might be associated with the malignant behaviors of TNBC.