Similar to other gene-silencing agents, targets of ribozyme for anti-cancer therapy are genes that are cancer-inducing, such as mutant K-ras [92] and fibroblast growth factor-2 (FGF-2) [93], or important for cancer survival, such as γ-Glutamylcysteine synthetase (γ-GCS) [94] and multiple drug resistance 1 (MDR-1) [95]. This evidence concerns the gene KRAS and cancer.