Synergistic Effect of Stereotactic Body Radiotherapy (SBRT) and Sini Decoction In a Lewis Lung Carcinoma Mouse Model
Abstract
Purpose
Stereotactic body radiotherapy (SBRT) modulates the tumor immune microenvironment and potentially induces the abscopal effect. Traditional Chinese medicine, Sini Decoction (SND), has demonstrated potential in enhancing immunity and inhibiting tumor metastasis. This study investigates the synergistic anti-tumor effects of SBRT combined with SND using an animal model.
Methods
Lewis lung carcinoma cells were fluorescently labeled and implanted subcutaneously into the abdomen of C57BL/6 mice. Simultaneously, tumor cells were injected via the tail vein to establish a lung cancer metastasis model. Twenty-four tumor-bearing mice were randomly divided into four groups (n=6 per group): Group 1 served as the control; Group 2 received SND via gavage (0.3 ml/dose) for two weeks; Group 3 underwent SBRT with a regimen of 8 Gy × 3 fractions targeting the subcutaneous tumor; Group 4 received the combined therapy of SBRT (8 Gy × 3 fractions) and SND via gavage. Whole-body fluorescence imaging was employed to monitor metastasis. Local tumor volume, metastatic burden, and overall survival (OS) were evaluated.
Results
Compared to the control group, SND administration alone did not significantly inhibit local tumor growth. SBRT effectively induced local tumor regression. Notably, the combined therapy group exhibited the most significant local tumor shrinkage. While SBRT alone improved local control, the combination of SBRT and SND significantly prolonged the overall survival of the mice.
Conclusion
The combination of SBRT and SND demonstrates a synergistic effect in suppressing local tumor growth , ultimately leading to a significant extension of overall survival in the Lewis lung carcinoma mouse model. This suggests a promising strategy for enhancing the efficacy of radiotherapy.