HOTAIR and breast cancer: Furthermore, exosomal lncRNA HOTAIR, UCA1 and H19 in drug-resistant breast cancer and exosomal lncRNA UCA1 in drug-resistant ovarian cancer seem to be promising diagnostic biomarkers and molecular targets to reduce drug resistance (Tang et al., 2019a; Xu et al., 2016; Wang et al., 2020; Li et al., 2019d).