MethHC 2.0 is a collective and comprehensive expression profile database composed of DNA methylation and mRNA/microRNAs in 33 Homo sapiens tumors and matched normal tissues. Similar to the previous database, this version uses textual and graphical interfaces when visualizing methylation pattern comparison of normal and tumor tissues. Therefore, users can compare methylation among several cancer types, pathological stage and cancers with or without mutation or with different copy number variations for a given gene