Acupuncture enhances anticancer effects of cyclophosphamide on 4T1 tumors via suppression of angiogenesis in BALB/c mice

Abstract

Objective: Acupuncture is considered an important part of the alternative medical treatment of tumors. However, it is still unclear whether acupuncture has a direct effect on inhibition of tumor growth. The purpose of this study was to evaluate the effects of acupuncture treatment on tumors in BALB/c mice that were or were not administered cyclophosphamide. Methods: A 4T1 breast carcinoma mouse model for this study was established. When the mice developed 5 mm × 5 mm visible subcutaneous tumors, they were subjected to acupuncture and/or cyclophosphamide (CTX) treatment for 15 days. Results: Acupuncture and CTX treatment both reduced the size of the solid tumors. When used in conjunction, the tumor size reduction was even more obvious. Hematoxylin and eosin staining showed that acupuncture had a significant effect on induction of tumor cell necrosis and inhibition of angiogenesis. Immunohistochemistry showed that the expression of CD34 and matrix metalloproteinase-9 (MMP-9), which were related to angiogenesis, decreased after treatment with either acupuncture or CTX. However, when the two treatments were used in conjunction, they showed a synergistic effect on inhibiting the expression of CD34. However, the synergistic effect was not observed on MMP-9 expression. Conclusion: Acupuncture plays an important role in improving the effect of chemotherapy by inhibiting angiogenesis.

Keywords

• Acupuncture
• Cyclophosphamide
• 4T1
• Angiogenesis
• BALB/c mice