<prompt> All of the following statement about vincristine are true exceptIt is cell cyclic specific and kills cells in the S phaseIts toxicity primarily affects bone marrow and epithelial structureFolic acid reverses its toxic effectsIt is a drug of choice for choriocarcinoma  <response>: Ref-KDT 6e 824,825 Vincristine is a vinca allkaloid. It acts in M-phase of cell cycle by inhibiting the formation of spindle. It is a marrow sparing drug and causes peripheral neuropathy as a prominent adverse effect. It is used for the treatment of hematological malignancies like Hodgkins lymphoma and leukemias.It is ineffective against solid tumors. 