Fig. 3

In vivo experiments confirmed that morphine exerts bidirectional effects on pancreatic cancer. a The effects of morphine (M) at doses of 0.5 mg/kg and 5 mg/kg on tumorigenesis were determined in a xenograft experiment. bIn vivo tumor growth curves were measured (n = 6). c The weights of tumor tissue were measured in the groups treated with M at doses of 0.5 mg kg⁻¹, 5 mg kg⁻¹, and the control group (n = 6). d There were no statistically significant differences in body weight between the groups of nude mice (morphine intervention in xenografted mice). e There were no statistically significant differences in body weight between the groups of nude mice (morphine intervention in normal mice). NS was administered based on the body weight of the control group. The number of mice used in each group was six. The data were expressed as mean ± SD, with *P < 0.05, **P < 0.01, and ***P < 0.001.