草分枝杆菌制剂对大鼠膀胱癌的抑制作用

Inhibitory effects of Mycobacterium phlei on bladder cancer in rats

目的探讨草分枝杆菌制剂连续膀胱灌注对大鼠膀胱肿瘤生长的抑制作用和机制。方法40只雌性Wistar大鼠,随机分为对照组(n=20)和草分枝杆菌组(n=20),制作N-甲基亚硝基脲诱导大鼠原位膀胱癌模型,于第8周开始分别行生理盐水和草分枝杆菌制剂连续膀胱灌注,每周1次,共6次。于第14周进行病理观察、测量膀胱总重量,微血管密度(MVD)和凋亡指数(AI)。结果第14周时,对照组(n=16)和草分枝杆菌组(n=14)大鼠膀胱均可见明显肿物,光镜下可见癌组织侵入肌层。草分枝杆菌组大鼠膀胱的重量和肿瘤的MVD小于对照组(t=2.609,P=0.048;t=2.124,P=0.043);草分枝杆菌组大鼠膀胱肿瘤的AI小于对照组但无统计学意义(t=0.583,P=0.565)。结论草分枝杆菌制剂连续膀胱灌注可抑制大鼠膀胱肿瘤生长,可能与抑制肿瘤血管生长有关。

Objective To investigate the inhibitory effects of Mycobacterium phlei preparation on orthotopic bladder carcinoma in rats and its mechanism. Methods Forty female Wistar rats were randomly divided equally into two groups： group I received normal saline plus N-methylnitrosourea as control and group Ⅱ received M. phlei preparation by intravesical perfusion （once a week for 6 weeks） for developing animal models. At week 14, the bladder weight, pathologic changes, rnicroveasel density（MVD） and apoptosis indexes（AI） were surveyed. Results There were obvious tumors in the both groups （ n = 16 in group Ⅰ and n = 14 in group Ⅱ ） at week 14. The tumors cells were infiltrated into the muscular layer of bladder. The bladder weights and MVDs were significandy lower in group Ⅱ than in group I （ P 〈 0.05 for both）, but there was no significant difference in AI between both groups （ P = 0. 565）. Conclusion Mycobacterlum phlei can inhibit the bladder tumor growth by restraining angiogenesis in rats.