Pinthus Jehonathan H, Kleinmann Nir, Tisdale Britton, Chatterjee Suman, Lu Jian-Ping, Gillis Aubrey, Hamlet Tamika, Singh Gurmit, Farrokhyar Forough, Kapoor Anil
Department of Surgery/Urology, McMaster University, Hamilton, Ontario, Canada.
Eur Urol. 2008 Oct;54(4):866-73. doi: 10.1016/j.eururo.2008.02.044. Epub 2008 Mar 11.
To examine a possible relationship between plasma adiponectin levels and renal cell carcinoma (RCC). Adiponectin, a cytokine secreted by adipocytes, is a potent antiangiogenic factor. Plasma levels of adiponectin in patients with RCC and tumor adiponectin receptors R1 and R2 (AdipoR1&2) expression levels were measured and correlated with disease characteristics.
Preoperative plasma samples from 42 patients were analyzed in triplicate for adiponectin levels with a specific ELISA assay. All patients had clear-cell RCC, including 15 with metastatic disease. Diabetic patients were excluded; all had normal renal function. The RCC and surrounding normal renal tissue were comparatively analyzed for AdipoR1&2 expressions (immunoblotting) in 15 patients.
Mean, median, and range of plasma adiponectin levels were 6.33, 5.84, and 1-25.2 microg/ml, respectively. A strong inverse correlation was found between plasma adiponectin levels and tumor size with significantly lower levels of adiponectin in tumors > or =4 cm (p<0.01). The median adiponectin levels in metastatic and nonmetastatic patients were 4.08 and 7.4 microg/ml, respectively (p=0.029). A trend toward significant lower adiponectin levels in high versus low Fuhrman grade (3 and 4 vs. 1 and 2) was noted (p=0.057). Expression of AdipoR1&R2 was found to be lower in tumor tissue compared with the patient's normal surrounding kidney tissues in 40% of the cases. Metastatic tumors expressed lower levels of AdipoR2. Body mass index was not inversely correlated with adiponectin levels.
Lower blood levels of adiponectin are positively associated with clear-cell RCC aggressiveness and could potentially be used as a biomarker.
研究血浆脂联素水平与肾细胞癌（RCC）之间可能存在的关系。脂联素是一种由脂肪细胞分泌的细胞因子，是一种有效的抗血管生成因子。测定了RCC患者的血浆脂联素水平以及肿瘤脂联素受体R1和R2（AdipoR1&2）的表达水平，并将其与疾病特征进行关联分析。
采用特异性ELISA法对42例患者的术前血浆样本进行三次重复检测，以分析脂联素水平。所有患者均为透明细胞RCC，其中15例有转移性疾病。排除糖尿病患者；所有患者肾功能均正常。对15例患者的RCC及周围正常肾组织进行AdipoR1&2表达（免疫印迹）的比较分析。
血浆脂联素水平的均值、中位数和范围分别为6.33、5.84和1 - 25.2微克/毫升。血浆脂联素水平与肿瘤大小之间存在强烈的负相关，肿瘤≥4厘米时脂联素水平显著降低（p<0.01）。转移性和非转移性患者的脂联素中位数水平分别为4.08和7.4微克/毫升（p = 0.029）。注意到高Fuhrman分级（3级和4级与1级和2级相比）患者的脂联素水平有显著降低的趋势（p = 0.057）。40%的病例中，肿瘤组织中AdipoR1&R2的表达低于患者周围正常肾组织。转移性肿瘤中AdipoR2的表达水平较低。体重指数与脂联素水平无负相关。
较低的血浆脂联素水平与透明细胞RCC的侵袭性呈正相关，有可能用作生物标志物。
