EXPERIMENTAL STUDY OF CRYOABLATION ON INVASION AND METASTASIS OF TRANSPLANTED TUMORS IN LEWIS LUNG CANCER MICE

Shuwei Zhang¹, Xing Chen², Fan Chen², Tianyang Dai^{1, *}

¹Department of Thoracic Surgery, The Affiliated Hospital of South West Medical University, Luzhou, 610072, China. 2Thoracic Surgery, Eastern Hospital, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, 610072, China

Lung cancer is a malignant tumor disease with a high case fatality rate and increasing morbidity yearly. It is highly concealed, and cancer cells can metastasize at an early stage. The commonly used method for this is cryoablation, which can effectively treat Lewis lung cancer and has many advantages such as being minimally invasive, having a small impact on lung function, and being able to be repeated. This article aims to investigate the effect of cryoablation on the invasion and metastasis of transplanted tumors in Lewis lung cancer mice and establish a controlled experiment. The experimental group was 15 C57BL mice undergoing a single-cycle freezing-rewarming ablation operation. When the ice ball covered the edge of the tumor, the mice were re-warmed to 0°C and 40°C. The control group was the same 15 Only C57BL mice without any intervention. On the 14th day after cryoablation, immunohistochemical methods were used to measure the amount of Twist, E-cadherin, and VEGF-A in tumor tissues. The study results showed that the body and tumor masses of the experimental group using cryoablation 14 days after surgery were 4%-10% lower than that of the control group. Immunohistochemical staining results showed that the protein expression of Twist and VEGF-A in the experimental group was 2% lower than that of the control group, and the protein expression of E-cadherin was 6% higher than that of the control group. The average tumor suppression rate in the experimental group is 16.45%. In addition, the re-warming at 0°C after cryoablation has a better inhibitory effect on tumor invasiveness and metastasis than that at 40°C. The mechanism is related to the inhibition of epithelial-mesenchymal transformation and tumor angiogenesis. Therefore, cryoablation has a specific inhibitory effect on the invasion and metastasis of transplanted tumors in Lewis lung cancer mice.