Department of Pathology, Shizuoka City Shimizu Hospital, Shizuoka, Japan.
Histol Histopathol. 2012 Mar;27(3):297-302. doi: 10.14670/HH-27.297.
The author investigated protein expression and gene mutations of KIT and PDGFRA in 61 consecutive surgical cases of renal cell carcinoma (RCC). The cases of RCC consisted of 43 clear cell RCC (CCRCC), 9 chromophobe RCC (ChrRCC), or 9 papillary RCC (PaRCC). Normal distribution of KIT and PDGFRA protein was also examined in non-tumorous normal parenchyma (n=10). In normal kidneys, KIT was expressed in distal convoluted tubules and collecting ducts, and PDGFRA in distal and proximal convoluted tubules and collecting ducts. KIT expression was recognized in 9 ChrRCC (100%, 9/9), but not in 43 CCRCC (0%, 0/43) and 9 PaRCC (0%, 0/9). PDGFRA expression was recognized in 7 CCRCC (16%, 7/43) and 2 PaRCC (28%, 2/9), but not in ChrRCC (0%, 0/9). A molecular genetic analysis using PCR-direct sequencing was performed in selected 30 cases (ChrRCC=9, CCRCC=12, PaRCC=9): it revealed no mutations in KIT (exons 9, 11, 13, and 17) or PDGFRA (exons 12 and 18) genes in any cases examined. These results suggest that in normal renal parenchyma KIT is expressed in distal convoluted tubules and collecting ducts, and PDGFRA in proximal and distal convoluted tubules and collecting ducts, that KIT is expressed exclusively in ChrRCC and its incidence is 100%, that KIT-positive ChrRCC was negative for PDGFRA, that PDGFRA is expressed in a small percentage in CCRCC and PaRCC, and that mutations of KIT (exons 9, 11, 13, and 17) and PDGFRA (exons 12 and 18) are absent in RCC.
作者研究了 61 例连续手术的肾细胞癌（RCC）中的 KIT 和 PDGFRA 蛋白表达和基因突变。这些 RCC 病例包括 43 例透明细胞 RCC（CCRCC）、9 例嫌色细胞 RCC（ChrRCC）或 9 例乳头状 RCC（PaRCC）。还检查了 10 例非肿瘤正常实质（n=10）中 KIT 和 PDGFRA 蛋白的正态分布。在正常肾脏中，KIT 在远曲小管和集合管中表达，而 PDGFRA 在远曲和近曲小管和集合管中表达。9 例 ChrRCC（100%，9/9）中检测到 KIT 表达，但 43 例 CCRCC（0%，0/43）和 9 例 PaRCC（0%，0/9）中未检测到。PDGFRA 在 7 例 CCRCC（16%，7/43）和 2 例 PaRCC（28%，2/9）中表达，但在 ChrRCC 中未表达（0%，0/9）。在选定的 30 例病例中进行了使用 PCR-直接测序的分子遗传学分析（ChrRCC=9、CCRCC=12、PaRCC=9）：在检查的任何病例中均未发现 KIT（外显子 9、11、13 和 17）或 PDGFRA（外显子 12 和 18）基因的突变。这些结果表明，在正常肾实质中，KIT 在远曲小管和集合管中表达，PDGFRA 在近曲和远曲小管和集合管中表达，KIT 仅在 ChrRCC 中表达，其发生率为 100%，KIT 阳性 ChrRCC 对 PDGFRA 呈阴性，PDGFRA 在 CCRCC 和 PaRCC 中的表达比例较小，KIT（外显子 9、11、13 和 17）和 PDGFRA（外显子 12 和 18）的突变在 RCC 中不存在。
