passages.id: split_4_test_526_passage
passages.type: progene_text
passages.text: This scFv was therefore used as control in experiments where another anti - Ras scFv ( Y259 scFv , derived from the neutralizing anti - Ras mAb Y13-259 ) blocked the Ras pathway in vitro and led to tumor regression in a nude mouse model [ Cochet , O. , Kenigsberg , M. , Delumeau , I. , Virone - Oddos , A. , Multon , M.C. , Fridman , W.H. , Schweighoffer , F. , Teillaud , J.L. , TocquÃ?Â© , B. , 1998. Intracellular expression of an antibody fragment - neutralizing p21 ras promotes tumor regression. Cancer Res. 58 , 1170 - 1176. ] .