ESR1 and breast cancer: As for E-Syt2, analysis of the expression of E-Syt2 at the transcript level revealed a significantly greater expression in the ER+ breast cancer cell lines MCF7 and T47D (Figure 1a; p < 0.0001) and was significantly attenuated in the TNBC cell line MDA-MB-231 as compared to non-tumoral MCF10A cells.