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目的 探讨大肠癌从大肠腺瘤伴轻度不典型增生到重度不典型增生到腺癌发展过程中肿瘤血管生成、细胞增殖、细胞凋亡的变化及其内在联系。方法 应用免疫组化方法测定增殖细胞核抗原(PCNA)和微血管密度(MVD)，用TUNEL法测定细胞凋亡。结果 (1)从腺瘤到腺癌的发展过程中，细胞增殖水平逐渐增高，细胞凋亡逐渐减少，MVD逐渐增多。而且腺瘤伴轻度不典型增生的肿瘤微血管与腺瘤伴重度不典型增生相比不仅形态上有差异，在数量差异也有显著性。(2)轻度不典型增生腺瘤PCNA与AI呈正相关性。(3)将所有大肠肿瘤作为一组分析，发现MVD与AI具有负相关性。结论 (1)血管生成抑制肿瘤细胞凋亡，促进肿瘤细胞增殖。(2)血管生成开关可能是在腺瘤伴轻度不典型增生向重度不典型增生和腺癌的转化过程中启动的。

Changes of angiogenesis,tumor cell proliferation and apoptosis during colorectal carcinogenesis

Objective To investigate the changes and the correlation of angiogenesis,tumor cell apoptosis and proliferation during colorectal carcinogenesis. Methods Proliferating cell nuclear antigen (PCNA) and microvessel density (MVD) was detected immunohistochemically.Apoptotic cells and bodies were detected with the TUNEL method in situ.Results (1)During the colorectal carcinogenesis,microvessel density and PCNA index had a gradual increment,whereas apoptosis index (AI) was declined;(2)The augmentation of apoptosis was revealed to parallel the increment of proliferative activity in adenomas with low dysplasia.(3)An inverse correlation between AI and MVD appeared when all of the lesions taken into account.Conclusion (1)Angiogenesis might play an additional role in inhibiting apoptosis and promoting cell proliferation.(2)The colorectal angiogenesis switch seems to be initiated during the transition of adenomas from low dysplasias to high dysplasias and carcinomas.