Can someone provide to me a brief summary on the functions of TRF1 within the mammalian shelterin complex? Also, if known, what are the effects of TRF1 inhibition or increased expression?

While some sources say TRF1 prevents telomerase from adding more telomere units (therefore TRF1 inhibition would promote tumor growth), other sources and published experiments found that TRF1 inhibitors suppressed tumor progression in cancer. Any chance to reconcile these differences?