Table 2.

Summary of gene therapy approaches.

S. no.	Gene therapy	Mechanism of action	Category	Indication
01	Oncolytic virotherapy (OV)	Directly lyses tumor cells and introduces wild-type tumor suppressor genes into cells	Naturally occurring or genetically modified viruses	Tumor immunotherapy
02	Gendicine	Induces the expression of p53, restores its activity, and destroys the tumor cells	Non-replicative adenoviral vector	Neck and head squamous cell carcinoma
03	Oncorine (rAd5-H101)	Causes oncolysis	Replicative, oncolytic recombinant ad5	Refractory nasopharyngeal cancer
04	Imlygic	Causes apoptosis of tumor cell	Genetically modified oncolytic HSV-1	Non-resectable metastatic melanoma
05	Rexin-G	Inhibits cell cycle in the G1 phase	Replication-incompetent retroviral vector	Metastatic cancers
06	Kymriah	Initiates the anti-tumor effect through CD3 domain	CAR T cell-based gene	Relapsed B-cell acute lymphoblastic leukemia
07	Zalmoxis	Enhances immune reconstitution	Allogeneic hematopoietic stem cell transplantation (allo-HSCT)	Hematopoietic malignancies