Gemcitabine causes telomere attrition by stabilizing TRF2.

Gemcitabine is an effective anti-cancer agent against solid tumors. The pharmacological mechanism of gemcitabine is known as incorporation into DNA and thereby inhibition of DNA synthesis. When used in metronomic chemotherapy of cancer, the agent may inhibit angiogenesis. It is still uncertain whether the agent can inhibit tumor growth by a mechanism other than DNA incorporation. In this report, we show that gemcitabine causes telomere shortening by stabilizing TRF2 that is required for XPF-dependent telomere loss. Overexpression of TRF2 in the absence of gemcitabine also causes telomere shortening with simultaneous association of TRF2 with XPF/ERCC1. Our study provides a new mechanism by which gemcitabine exerts its anti-tumor activity.