Role of the Chinese Herbal Medicine Xianhuayin on the Reversal of Premalignant Mucosal Lesions in the Golden Hamster Buccal Pouch

Aim To investigate the role of the Chinese herbal medicine Xianhuayin on the reversal of 7,12-dimethylbenz[a]anthracene （DMBA）-induced premalignant mucosal lesions in the oral buccal pouch of golden hamsters. Methodology The animals were randomly divided into a non-diseased control group （n=5） and an experimental group including 50 animals in which the buccal mucosa had been painted with DMBA （0.5% in acetone） to generate an oral mucosa premalignant lesion. Animals in the experi- mental group were further divided into Xianhuayin-treated group （n=30）, untreated prem＇alignant lesion group （n=10） and normal saline （NS）-treated group （n=10）. The cheek （buccal） pouch mucosa of the golden hamsters in each group was observed with light and electron microscopy eight weeks after intragastric administration with NS or Xianhuayin. Results In the non-diseased control group, the buccal mucosa was keratinized and stratified squamous epithelium under a light microscope. In the untreated premalignant lesion group, variable degrees of epithelial dysplasia was observed. The irregular epithelial mucosa gradually became distinct in the Xianhuayin-treated group. Scanning electronic microscopic （SEM） analysis showed that surface of the cells exhibited honeycomb structures in the hamster of untreated- group. The cells were morphologically irregular, overlapped and loosened in the untreated premalignant lesion group. Most of the cell surface exhibited honeycomb structure in the Xianhuayin-treated group. Transmission electronic micro- scopic （TEM） analysis showed that buccal mucosal epithelial cells were morphologically regular in the non-diseased control group. Desmosomes and tonofibrils were reduced and the nucleus was morphologically irregular in the untreated premalignant lesion group. In the Xianhuayin-treated group, the widening intercellular gap was gradually reduced, desmosomes and the cells becoming morphologically regular. No significant difference was observed between the hamsters in NS-treated group and those in the untreated premalignant lesion group. Significant therapeutic efficacy was observed in the group receiving Xianhuayin. Conclusion Xianhuayin is effective in the reversal of DMBA-induced premalignant lesions in the buccal pouch of golden hamsters.

中国地鼠口腔颊囊黏膜癌模型的建立及癌变的动态观察

目的:利用二甲基苯并蒽(DMBA)涂抹法建立中国地鼠颊囊黏膜癌的实验动物模型,观察癌变不同时期的组织学动态变化过程。方法:将60只雄性中国地鼠随机分为3组,分别为模型组(24只)、溶剂对照组(12只)、空白对照组(24只)。溶剂对照组仅涂丙酮液,空白对照组不作任何处理,模型组以0.5%DMBA涂抹中国地鼠两侧颊囊,每周3次,共15周。分别于第6、9、12、15周将模型组和空白对照组随机处死6只,溶剂对照组处死3只,在肉眼及光镜下动态观察颊囊黏膜癌变全过程的形态学和显微组织学改变。结果:与对照组比较,DMBA长时间处理后模型组地鼠相继出现口腔内黏膜充血、增厚、溃烂化脓、白斑及菜花状赘生物等变化,经历了单纯上皮增生(6~9周)、不同程度上皮异常增生(9~12周)、原位癌及鳞状细胞癌(12~15周)等阶段。结论:DMBA涂抹法可成功建立中国地鼠颊囊黏膜癌前病变、鳞状细胞癌模型,发病过程与人类口腔鳞状细胞癌相似,为口腔鳞癌的多阶段、多步骤研究提供了一个较为理想的动物模型。

地鼠颊粘膜癌变过程中增殖细胞核抗原及核仁组成区表达变化实验研究

目的 :探讨癌变过程中增殖细胞核抗原 (PCNA)、核仁组成区 (NOR)的表达变化。方法 :利用地鼠颊粘膜癌模型采用免疫组化LSAB法检测PCNA ,阳性对照为人类炎性增生淋巴结标本 ,阴性对照为PBS代替单抗。采用硝酸银染色法检测NOR。结果 :①正常粘膜AgNOR颗粒主要见于基底层细胞 ,以单一型为主。重度异常增生以聚集型为主。浸润癌以混合型为主。②随恶变进展 ,PCNA表达逐渐增强 ,重度异常增生阳性细胞见于上皮全层。结论 :PCNA与AgNOR表达有相关性 (r =0 6 35 ,P <0 0 0 1) ,但PCNA更为直观 ,清晰 ,实用价值更大。