Ym. Lin et al., Identification of AF17 as a downstream gene of the beta-catenin/T-cell factor pathway and its involvement in colorectal carcinogenesis, CANCER RES, 61(17), 2001, pp. 6345-6349
To elucidate the molecular mechanism of colorectal carcinogenesis, we have
been attempting to isolate genes involved in the beta -catenin/T-cell facto
r pathway. In the experiments reported here, analysis by cDNA microarray in
dicated that AF17, a fusion partner of the MLL gene in acute leukemias with
t(11;17)(q23;q21), was transactivated according to accumulation of beta -c
atenin. Expression of AF17 was significantly enhanced in 8 of the 12 colore
ctal cancer tissues examined. Introduction of a plasmid designed to express
AF17 stimulated growth of NIH3T3 cells, and fluorescence-activated cell so
rter analysis indicated that the AF17 regulation of cell-cycle progression
was occurring mainly at the G(2)-M transition. Our results suggest that the
AF17 gene product is likely to be involved in the beta -catenin-T-cell fac
tor/lymphoid enhancer factor signaling pathway and to function as a growth-
promoting, oncogenic protein. These findings should aid development of new
strategies for diagnosis, treatment, and prevention of colon cancers and ac
ute leukemias by clarifying the pathogenesis of these conditions.