CAR-T cell immunotherapy is the last choice for treating cancer when the patient is not responsive to all other cancer therapies. However, the survival of CAR-T cells in the body is insufficient to kill all cancer cells, especially in targeting solid tumors in most cases. With our discovery, we can enhance the CAR-T cells' survival in the patient, providing it with the necessary tools to attack and eradicate solid tumors as well. The outcome of our study on the survival cytokine will pave the way for researchers around to world to study the survival cytokine which can be utilized to fit other applications in healthcare. PROCAR-T has an "on/off" system integrated into the construct of CAR-T. Once PROCAR-T has been administered to the patient post-activation in the lab, PROCAR-T will produce and secrete survival cytokine in the patient's body. The survival cytokine will function in a positive feedback mechanism which will produce more survival cytokine in the presence of the cytokine. Once all the tumors and cancer tissues in the patient have been killed, the switch-off drug can be administered to the patient which will terminate all the PROCAR-T in the body turning off the production of survival cytokine. Our "on/off" system will ensure that the patient won't be affected by cytokine storm which will lead to multiple side effects in the body.