Gasinska Anna, Jaszczynski Janusz, Adamczyk Agnieszka, Janecka-Widła Anna, Wilk Waclaw, Cichocka Anna, Stelmach Andrzej
Department of Tumor Pathology, Maria Sklodowska-Curie Institute, Oncology Center, Cracow Branch, Poland.
Folia Histochem Cytobiol. 2018;56(4):195-206. doi: 10.5603/FHC.a2018.0023. Epub 2018 Dec 20.
It has been suggested that the metastatic potential of neoplastic cells can be predicted on the basis of their biological features, including expression of proteins involved in the epithelial to mesenchymal transition (EMT). Therefore, the purpose of this work was to (1) evaluate the expression of EMT markers: ZEB2, vimentin, N-cadherin, TWIST, PTEN, survivin, E-cadherin, Ki-67 and GLUT-1, (2) assess mutation status of two genes: PIK3CA and KRAS, and (3) investigate the potential relationships between the studied biomarkers and clinicopathological factors in clear-cell renal cell carcinoma (ccRCC).
Tumor tissue samples (embedded in paraffin blocks) from 159 patients undergoing radical nephrectomy were analyzed. Proteins expression was evaluated immunohistochemically. DNA mutations were analyzed on DNA isolated from tumor tissue and amplified by real-time PCR detection using suitable fluorescent labeled TaqMan assays.
One hundred and seven men and 52 women of mean age of 63.1years were enrolled. Fifty four cancers at pTNM stage I-II and 98 at pTNM III-IV stage were diagnosed. There were 30 Fuhrman grade G1, 61 Fuhrman G2, 49 Fuhrman G3 and 19 Fuhrman G4 tumors. A negative correlation between ZEB2 (p = 0.047, r = -0.172) or E-cadherin expression (p = 0.027, r = -0.191) and TNM was observed. Positive association between grade and Ki-67 (p < 0.001), survivin (p < 0.001), vimentin (p < 0.001) immunoreactivity and negative association between TWIST expression (p = 0.029) or PTEN expression (p = 0.013) were found. Ki-67 expression was positively correlated with survivin (p < 0.001, r = 0.617), vimentin (p = 0.001, r = 0.251) and N-cadherin (p = 0,009, r = 0.207) immunoreactivity which can suggest tumor aggressiveness. TWIST was negatively correlated with E-cadherin (p < 0.001, r = -0.284), vimentin (p < 0.001, r = -0.297) and N-cadherin (p < 0.002, r = -0.241). ZEB2 was not associated with ccRCC grade but was negatively correlated with E-cadherin (p = 0.055, r= -0.153) and PTEN (p = 0.006). GLUT-1 expression was inversely linked to E-cadherin expression (p = 0.022, r= -0.182). Mutations in PIK3CA and KRAS genes were not found in any of the studied ccRCC tumors.
Low-grade tumors showed higher expression of ZEB2 and TWIST proteins than high-grade tumors, which can suggest that EMT in ccRCC begins at early stages of tumor development and, therefore, evaluation of these proteins, together with other biomarkers, may be useful for assessment of the tumor metastatic potential.
有人提出，可以根据肿瘤细胞的生物学特征，包括参与上皮-间质转化（EMT）的蛋白质表达，来预测肿瘤细胞的转移潜能。因此，本研究的目的是：（1）评估EMT标志物ZEB2、波形蛋白、N-钙黏蛋白、TWIST、PTEN、生存素、E-钙黏蛋白、Ki-67和葡萄糖转运蛋白1（GLUT-1）的表达；（2）评估两个基因PIK3CA和KRAS的突变状态；（3）研究透明细胞肾细胞癌（ccRCC）中所研究的生物标志物与临床病理因素之间的潜在关系。
分析了159例行根治性肾切除术患者的肿瘤组织样本（石蜡包埋）。采用免疫组织化学法评估蛋白质表达。对从肿瘤组织中分离的DNA进行DNA突变分析，并使用合适的荧光标记TaqMan检测法通过实时PCR检测进行扩增。
共纳入107例男性和52例女性，平均年龄63.1岁。诊断出54例pTNM I-II期癌症和98例pTNM III-IV期癌症。有30例Fuhrman 1级、61例Fuhrman 2级、49例Fuhrman 3级和19例Fuhrman 4级肿瘤。观察到ZEB2（p = 0.047，r = -0.172）或E-钙黏蛋白表达（p = 0.027，r = -0.191）与TNM之间呈负相关。发现分级与Ki-67（p < 0.001）、生存素（p < 0.001）、波形蛋白（p < 0.001）免疫反应性呈正相关，与TWIST表达（p = 0.029）或PTEN表达（p = 0.013）呈负相关。Ki-67表达与生存素（p < 0.001，r = 0.617）、波形蛋白（p = 0.001，r = 0.251）和N-钙黏蛋白（p = 0.009，r = 0.207）免疫反应性呈正相关，这可能提示肿瘤侵袭性。TWIST与E-钙黏蛋白（p < 0.001，r = -0.284）、波形蛋白（p < 0.001，r = -0.297）和N-钙黏蛋白（p < 0.002，r = -0.241）呈负相关。ZEB2与ccRCC分级无关，但与E-钙黏蛋白（p = 0.055，r = -0.153）和PTEN（p = 0.00）呈负相关。GLUT-1表达与E-钙黏蛋白表达呈负相关（p = 0.022，r = -0.182）。在所研究的任何ccRCC肿瘤中均未发现PIK3CA和KRAS基因的突变。
低级别肿瘤中ZEB2和TWIST蛋白的表达高于高级别肿瘤，这可能表明ccRCC中的EMT在肿瘤发展的早期阶段就开始了，因此，评估这些蛋白质以及其他生物标志物可能有助于评估肿瘤的转移潜能。
