The cancer stem cell (CSC) theory is current strategy of cancer treatment. Cancers follow pathways of cancer stem cell such as Notch, Wnt and Hedgehog can be addressed with natural products or synthetic drugs to diminish the chance of new tumours. The cancer growth can also be suppressed by aiming the tumourigenic stem cells alone, instead of targeting at reducing complete tumour dimension. The recurrence of tumours after years of disease-free survival has prompted interest in the concept that cancers may have a stem cell basis. Current assumption holds that < 5% of the tumour mass may be chemo-resistant and radio-resistant, harbouring stem-like properties that impel tumour survival, development, and metastasis. There is intense an investigation to interpret CSCs based on self-renewal and multi-lineage differentiation. Nevertheless, no successful targeted therapies have reached the clinic. The ionophore antibiotic salinomycin that selectively kills breast CSCs seems to be a promising anticancer drug. Clinical trials conducted by the NIH (National Institute of Health) on several synthetic drugs demonstrate the current importance of the issue and predict a bright future for such molecular weapons against cancer.