2. Materials andmethods
2.1. Sequence retrieval, alignments, and expression data acquisition
In total, 69 tumor suppressor genes (the list are in Supplementary File 1) which code proteins with different molecular functions and localizations in the cell, were extracted along with their normalized mRNA expression directly from SOURCE, 2009 (Stanford Microarray) database(source.stanford.edu). This database links to microarray experimentsthat included the queried gene. Their CDS and protein sequenceswere ob-
tained from NCBI database. Because of minimizing the statistical errors,multiple alignments were performed for obtained sequences by ClustalW program(http://www.ebi.ac.uk). Twenty five tissues were selected and in each tissue the average expression level, the number of expressed genes, and the highest expressed gene were recognized.