Description A phase II metabolic enzyme, NAT1 is frequently upregulated in breast cancers. Previous studies have shown that inhibition or depletion of NAT1 in breast cancer cell lines leads to growth retardation both in vitro and in vivo, suggesting that NAT1 contributes to rapid growth of breast cancer cells. This project evaluated the effects of NAT1 knockdown on the proteome of a breast cancer cell line.hese groups include a parental MDA-MB-231 breast cancer cells and two separate NAT1 knockout (KO) cell lines differing by proliferation rates.