breast cancer tissues, cell lines (T47D, MDA-MB-231)
Here, we observed that 91H, H19 and IGF2 are overexpressed in breast tumors. By using 91H-knockdown breast cancer cells, we demonstrated that 91H exerts oncogenic properties by promoting cell growth, migration and invasion as well as tumor growth in xenografted immunodeficient mouse model. Moreover, 91H-knockdown reduces the expression of H19 and IGF2 in breast cancer cells. By chromatin-immunoprecipitation and methylation studies, we found that 91H expression prevents histone and DNA methylation on the maternal allele at the H19/IGF2 locus.