As tumor tissues are weakly acidic, a fusion protein Trx-pHLIP-Beclin 1 is designed to specifically accumulate in weakly acidic conditions (pH 6.5); Trx-pHLIP-Beclin 1 induces autophagic cell death in breast and ovarian cancer cells and suppresses growth of ovarian cancer xenografts, without causing systemic toxicity (Ding et al., 2018). Here, BECN1 is linked to ovarian cancer.