This invention generally relates to a composition and its method of use for inducing adult stem cell (ASC) expansion and/or derivation in vitro, using miR-302-like pre-miRNAs, shRNAs and/or siRNAs, all of which contain a shared sequence of 5′-UAAGUGCUUC CAUGUUU-3′ (SEQ ID NO: 7) in the 5′-end, and further in conjunction with the use of some wound-healing-related defined factors, including but not limited to basic fibroblast growth factor (bFGF)/fibroblast growth factor 2 (FGF-2), leukemia inhibitory factor (LIF), insulin-like growth factor (IGF), Epidermal growth factor (EGF), platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), transforming growth factor (TGF), tumor necrosis factor (TNF), stem cell factor (SCF), homeobox proteins (HOX), Notch, GSK, Wnt/beta-Catenin signals, interleukins, and/or bone morphogenetic proteins (BMPs). The principle of the present invention is related to a novel mechanism of inducible symmetric ASC division recently found in a skin wound healing model in vivo. The resulting amplified ASCs are useful for treating a variety of human aging- and cell dysfunction-associated disorders, including but not limited to Alzheimer's disease, Parkinson's disease, motor neuron disease, stroke, diabetes, osteoporosis, myocardial infraction, hemophilia, anemia, AIDS, leukemia, lymphoma and many kinds of cancers as well as aging.