Tacalcitol monohydrate (CAS No 93129-94-3) is a synthetic vitamin D3 analog used in biomedical research particularly in dermatology and oncology studies Originating from chemical synthesis it primarily acts on the vitamin D receptor modulating gene expression to influence cell differentiation and proliferation Its mechanism involves the inhibition of keratinocyte proliferation and the promotion of their differentiation proving effective in treating conditions like psoriasis In vitro Tacalcitol monohydrate exhibits activity in the nanomolar to low micromolar range It is commonly used in various experimental models including cultured cell lines and animal studies to investigate skin-related disorders and potential anticancer properties Drug screening applications also utilize this compound to explore novel therapeutic targets or formulations Experimental concentrations typically depend on the specific research design