H2AX and neoplasm: The plots generated based on data obtained from the NCI-60 cancer cell line panel [23] and the Cancer Cell Line Encyclopedia (CCLE) [24] show that while the number of copies of the H2AX gene roughly correlates with the number of mRNA transcripts (correlation coefficients of 0.75 for NCI-60 and 0.45 for CCLE), the association is not strong enough to accurately predict H2AX protein expression based on gene copy number in tumor cells (S1A and S1B Fig).