中文摘要：

目的：研究肺肉瘤样癌（pulmonal7SaF（-omatoidearcillOllla，PSC）中血管生成拟态（vasculogenicmimicry，VM）的临床意义，阐述上皮间充质转化（epithelial—to—mesenchymaltransition，EMT）提高PSC的恶性度及促进VM形成的相关机制，方法：对肺肉瘤样癌组织切片22例进行HE、CD3l和PAS双重染色，Twist、Vimentin、E-cadherin、VEGF免疫组织化学染色，分析VM相关的临床意义及EMT促进VM形成的相关机制结果：22例中4例（18．2％）存在vM，Kaplan—Meier生存分析提示有无VM肿瘤患者比较生存时间差异有统计学意义（P〈O．05）：VM阳性患者Twist的阳性率较阴性患者高，且差异有统计学意义（P〈O．05）、Twistl的表达与VEGF、E-cadherin、Vimentin的表达存在明显相关性结论：VM是患者预后的不利因素，肺肉瘤样癌中发生了EMT，转录因子Twistl可能通过下调E-cadherin，上调Vimentin诱导EMT，并可能通过上调VEGF的表达促进VM的形成，从而促进肿瘤的侵袭和转移

英文摘要：

Objective： The expression and clinical significance of vasculogenic mimicry （VM） were investigated. The related mechanisms of epithelial-to-mesenchymal transition （EMT） in VM formation and worsening of puhnonary sarcomatoid carcinoma （PSC） were examined. Methods： Hematoxylin and eosin staining, CD31/periodic acid-Schiff double staining, and immunohistochemi- cal staining were performed to determine the expression of VM, Twist l, vascular endothelial growth factor （VEGF）, E-cadherin, and vi- mentin in the tissues of 22 PSC patients. The clinical significance of VM and the mechanism of EMT in VM formation were explored. Results： VM was found in four （18.2%） of the 22 PSC patients. Kaplan Meier survival analysis revealed that the patients with VM had a shorter survival period than those without the VM expression, with statistically significant differences found between the two groups. Comparative results of the groups with and without VM expression showed a higher positive rate of Twistl expression in the former group （P〈0.05）. Significant correlations were observed between the Twistl expression and the VEGF, E-cadherin, and vimentin expression. Conclusion： VM unfavorably influences the prognosis of PSC patients. Twistl can upregulate Vimentin and downregulate E-cadherin by inducing EMT. Additionally, it may upregulate VEGF to promote VM formation, which increases tumor invasions and metastases.