The present invention relates to a keratinocyte growth factor fragment, KGFdes1-23, that is composed of a portion of an amino acid sequence of mature, full length keratinocyte growth factor, KGF163. The portion possesses at least a 2-fold increase in mitogenic activity as compared to a mature, recombinant keratinocyte growth factor, rKGF, but lacks a sequence comprising the first 23 amino acid residues, C-N-D-M-T-P-E-Q-M-A-T-N-V-N-C-S-S-P-E-R-H-T-R- of the KGF163 N-terminus. The present invention also relates to a DNA molecule encoding KGFdes1-23, an expression vector and a transformed host containing the DNA molecule, and a method of producing KGFdes1-23 by culturing the transformed host. The present invention further relates to a conjugate of KGFdes1-23 and a toxin molecule, and the use thereof for treatment of hyperproliferative disease of the epidermis. Moreover, the present invention relates to a therapeutic composition containing KGFdes1-23 and a pharmaceutically acceptable carrier and the use thereof for wound healing purposes.