Abstract. The present study aimed to investigate the potential effect of leucine-rich repeat containing 3B (LRRC3B) with respect to the inhibition of breast cancer recurrence and metastasis post-anesthesia. The mRNA expression of LRRC3B in breast MDA-MB-231 and MCF-7 cell lines was detected using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. The effect of bupivacaine on breast cancer cell invasion was analyzed using a Matrigel assay. LRRC3B specific small interfering (si)RNA was constructed and transfected into breast cancer cells using Lipofectamine ® 2000 reagent. The influence of bupivacaine on LRRC3B expression was measured based on RT-qPCR. Additionally, the effect of LRRC3B silencing on the invasion of breast cancer cells treated with bupivacaine was analyzed. Compared with the control, LRRC3B expression significantly increased in MDA-MB-231 and in MCF-7 cells as the length of time increased (P<0.05), but the expression of the gene significantly declined in 2 types of cancer cell when the cells were transfected with siRNA-LRRC3B plasma (P<0.05). The administration of 50 µg/ml bupivacaine promoted maximum breast cancer cell invasion, and suppressed LRRC3B mRNA expression in cells. However, when LRRC3B was silenced in cancer cells, 20 µg/ml bupivacaine significantly promoted cancer cell invasion, indicating that bupivacaine suppresses the expression of LRRC3B and promotes cell invasion. The present study suggested that LRRC3B serves a protective role in preventing bupivacaine-induced breast cancer recurrence and metastasis.