GENE-THERAPY AGAINST CANCER AND HIV-INFECTION USING THE GENE ENCODINGHERPES-SIMPLEX VIRUS THYMIDINE KINASE

The expression of the gene encoding herpes simplex virus thymidine kin ase (HSV-TK) in eukaryotic cells confers sensitivity to antiherpetic d rugs such as acyclovir and ganciclovir. This property has been propose d for use in gene therapy approaches to kill either cancer cells or HI V-infected cells. Several animal experiments have shown the regression of tumors after in vivo transfer of the HSV-TK gene followed by ganci clovir treatment. Furthermore, CD4(+) T cells harboring the HSV-TK gen e under the control of HIV regulatory sequences are protected from HIV spreading in the presence of acyclovir. Thus, the HSV-TK gene has pot ential applications in gene therapy for the treatment of cancer and HI V infection.