However, in vitro overexpression of some BER proteins, such as MPG (N-methylpurine-DNA glycosylase), but not of others, such as XRCC1 (X-ray repair cross-complementing group 1), results in increased sensitivity of CRC cells to both 5-FU and the alkylating agent temozolomide, suggesting that BER modulation can alter the response to drug-induced DNA damage, making it a promising target for CRC therapy [145]. Here, XRCC1 is linked to colorectal carcinoma.