▁+ 1 ▁in ▁the ▁DNA ▁sequence . ▁ ▁One ▁ir in ot ec an ▁or ▁SN - 3 8 ▁mole c ule ▁stack s ▁against ▁the ▁base ▁pairs ▁fl ank ing ▁the ▁to pois omer ase - indu ced ▁cle av age ▁site ▁and ▁po isons ▁( in activ ates ) ▁the ▁T OP 1 ▁en zym e . ▁ ▁The ▁article ▁Cam pt othe cin ▁lists ▁other ▁analog ues ▁of ▁cam pt othe cin ▁and ▁the ▁article ▁Top ois omer ase ▁in hib itor ▁lists ▁other ▁comp ounds ▁which ▁in hib it ▁T OP 1 . ▁ ▁Can cer ▁ ▁Since ▁ 1 9 8 5 , ▁T OP 1 ▁has ▁been ▁known ▁as ▁a ▁target ▁for ▁the ▁treatment ▁of ▁human ▁can cers . ▁Cam pt othe cin ▁analog ues ▁ir in ot ec an ▁and ▁top ot ec an , ▁which ▁in hib it ▁T OP 1 , ▁are ▁among ▁the ▁most ▁effective ▁F DA - appro ved ▁ant ican cer ▁chem other ape ut ic ▁agents ▁used ▁in ▁clin ical ▁practice . ▁High er ▁expression ▁of ▁T OP 1 ▁in ▁K R AS ▁mut ant ▁non - small ▁cell ▁lung ▁cancer ▁and ▁correlation ▁to ▁surv ival ▁suggests ▁that ▁T OP 1 ▁in hib itors ▁might ▁have ▁increased ▁benefit ▁when ▁admin ister ed ▁to ▁treat ▁patients ▁with ▁a ▁K R AS ▁mut ant ▁tum or . ▁ ▁Syn th etic ▁le th ality ▁ ▁Syn th etic ▁le th ality ▁ar ises ▁when ▁a ▁combination ▁of ▁def ic ien cies ▁in