Cancer stem cells play a crucial role in tumors'invasion, metastasis, recurrence and drug resistance.Investigation on the chemicals with tumor stem cell growth inhibitory activity has been greatly highlighted in the field of anti-tumor drug discovery.This paper briefly reviews the recent progress of chemical investigations on substances with tumor stem cell growth inhibitory activity , aiming to give readers a reference on anti-tumor drug discovery.

Objective To explore the effect of repetitive transcranial direct current stimulation(tDCS)on anti-fatigue capacity,power output,and muscle activation during continuous vertical jumps of aver-age undergraduates.Methods Thirty healthy male college students were randomly assigned to an anodal tDCS(a-tDCS)group and a sham tDCS(sham-tDCS)group,receiving a total of 10 repeated anodal tDCS and sham tDCS for 5 consecutive days on the primary motor cortex respectively.Before and right after the intervention,as well as one month after the intervention,all students underwent the continuous vertical jump test.The two-factor repeated measure ANOVA(stimulation condition×time)was employed to evaluate alterations in fatigue index,total jump height,lower limb stiffness and mus-cle activation characteristics.Results The fatigue index of the a-tDCS group was significantly lower than the sham-tDCS group(P<0.05).After a-tDCS,the total jump height was significantly higher than before(P<0.05).In the sham-tDCS group,the touchdown time during continuous vertical jumps in-creased more significantly right and a month after the intervention(P<0.05 for both).Moreover,lower limb stiffness of the a-tDCS group at the last moment of the continuous vertical jumps was significant-ly higher than the sham-tDCS group(P<0.05).After a-tDCS,the activation of the rectus femoris mus-cle increased significantly in the eccentric phase of the end of the test(P<0.05).However,no signifi-cant differences were found in the mean power and post-test rating of perceived exertion after the stim-ulation.Conclusion Ten sessions of tDCS conducted over five consecutive days demonstrates an en-hancement in neuromuscular activation during high-intensity jumping exercise.This observed augmenta-tion contributes to attenuating the decline in exercise capacity associated with fatigue.