Aoyagi T, Takishima K, Hayakawa M, Nakamura H
Department of Urology, National Defense Medical College, Saitama, Japan.
Int J Urol. 1996 Sep;3(5):392-6. doi: 10.1111/j.1442-2042.1996.tb00560.x.
Renal cell carcinoma (RCC) is thought to arise from the renal tubular cells (RTC). Assuming that proliferating RTC imply a premalignant change of RTC into RCC, messenger RNA expressions of growth factors in cultured RTC were compared to both cultured and frozen noncultured RCC.
The expression of transforming growth factor-alpha (TGF-alpha), epidermal growth factor (EGF), EGF receptor (EGFR) and interleukin-6 (IL-6) were studied in surgically obtained RCC (n = 17), cultured RCC (n = 10), and autologous cultured RTC (n = 15). Quantitation of the PCR product was performed using a computer image analyzer which evaluated the intensity of each cytokine relative to beta-actin.
TGF-alpha, EGFR and IL-6 were detected in most of the cultured RTC, and both cultured and noncultured RCC were also expressed at high levels. In contrast to a high positivity of TGF-alpha, EGF was not strongly positive in all specimens.
Our results show that there is a predominant autocrine production of TGF-alpha in RCC and RTC, suggesting that TGF-alpha plays a distinct role in the proliferation of these cells. These studies also indicate that the mechanisms of proliferation and cytokine production of RCC and RTC are similar.
肾细胞癌（RCC）被认为起源于肾小管细胞（RTC）。假设增殖的RTC意味着RTC向RCC的癌前变化，将培养的RTC中生长因子的信使核糖核酸表达与培养的和冷冻的未培养RCC进行比较。
研究了手术获取的RCC（n = 17）、培养的RCC（n = 10）和自体培养的RTC（n = 15）中转化生长因子-α（TGF-α）、表皮生长因子（EGF）、EGF受体（EGFR）和白细胞介素-6（IL-6）的表达。使用计算机图像分析仪对PCR产物进行定量，该分析仪评估每种细胞因子相对于β-肌动蛋白的强度。
在大多数培养的RTC中检测到TGF-α、EGFR和IL-6，培养的和未培养的RCC也高水平表达。与TGF-α的高阳性率相反，EGF在所有标本中并非强阳性。
我们的结果表明，RCC和RTC中存在主要的TGF-α自分泌产生，提示TGF-α在这些细胞的增殖中起独特作用。这些研究还表明，RCC和RTC的增殖机制和细胞因子产生机制相似。
