Controlling cancer by restricting arginine availability--arginine-catabolizing enzymes as anticancer agents.

Interest has recently been revived in enzymes that degrade essential amino acids. Arginine-catabolizing enzymes now predominate and are discussed in this review. Apart from reducing tumor load through cell death occurring as a result of deprivation alone, these catabolic enzymes conveniently leave the remaining malignant cells vulnerable to other therapeutic modalities through combinatorial treatments with cycle-dependent drugs, the timing of additional treatment after deprivation being crucial.