Trichosanthin induces anti-cancer effects by increasing the penetration of Granzyme B into tumor cells

Trichosanthin (TCS), known as a plant toxin, is applied as a midterm abortifacient in clinics, and currently reported to exhibit other biological and pharmaceutical effects such as anti-tumor, anti-HIV, and Immunoregulation. TCS was found out to firmly inactivate the ribosomes of the eukaryotic cell, but this finding was far enough to explain its various biological and pharmaceutical effects. Our previous studies focused on exploring novel TCS binding proteins, as to reveal new mechanisms in mammalian cells. And we found out that TCS and cation-independent mannose-6-phosphate receptor (CI-MPR) competitively bind to Golgi-localized, γ-ear containing and Arf-binding proteins (GGA), which finally increased the cell permeability of Granzyme B and promoted the cytotoxic T lymphocyte-mediated tumor cell apoptosis.