血小板衍生生长因子B及其受体的表达对肾癌ACHN细胞增殖的影响

Effect of platelet derived growth factor-B and its receptor expression on the proliferation of renal cell carcinoma ACHN cells

目的：通过体内外实验探讨血小板衍生生长因子B（ PDGF－B）及其受体（ PDGFR－β）的表达对肾癌ACHN细胞增殖的影响。方法将PDGF－B表达质粒转染入肾癌ACHN细胞，采用四甲基偶氮唑蓝（ MTT）法检测转染前后ACHN细胞增殖能力的变化，采用Western blot法检测PDGF－B过表达对血管内皮细胞和平滑肌细胞中磷酸化PDGFR－β（ p－PDGFR－β）表达的影响。将转染PDGF－B的ACHN细胞种植于小鼠皮下，建立肾癌移植瘤模型，观察移植瘤体积的变化，并以免疫组化SP法检测肿瘤组织中Ki－67的表达情况。结果转染组ACHN细胞中PDGF－B的表达较未转染组明显增高。MTT法检测结果显示，PDGF－B转染并未使ACHN细胞的增殖受到明显抑制。在PDGF－B过表达的培养液中培养后，血管平滑肌细胞中p－PDGFR－β的表达明显上调。转染组和未转染组小鼠移植瘤的肿瘤体积分别为（0．305±0．108）cm3和（0．577±0．218）cm3，转染组肿瘤体积明显变小（P＝0．007）。转染组和未转染组肿瘤组织中Ki－67阳性的肿瘤细胞数量分别为（41．00±5．34）个／高倍视野和（55．80±2．95）个／高倍视野，转染组肿瘤组织中Ki－67的阳性表达量明显下降（ P＝0．001）。结论在肾癌中，PDGF－B的过表达可上调血管平滑肌细胞中p－PDGFR－β的表达水平，从而通过旁分泌信号通路抑制肾癌细胞的增殖和移植瘤的生长。

Objective To study the effect of platelet derived growth factor-B and its receptor expression on the proliferation of renal cell carcinoma ACHN cells in vitro and in vivo.Methods PDGF-B gene was transfected into human renal carcinoma cell line ACHN cells, and the proliferation capability of ACHN cells transfected with or without PDGF-B was assessed by MTT assay.The effect of PDGF-B on the expression of p-PDGFR-βin endothelial cells and vascular smooth muscle cells （ VSMC ） was detected by Western blot.ACHN cells transfected with PDGF-B were injected into mice （ untransfected ACHN as control） to induce tumor formation.Immunohistochemical staining was used to detect the expression of Ki-67 in tumor cells and the tumor volume was measured to compare the tumor growth in the two groups.Results The PDGF-B expression of ACHN cells in transfected group was significantly increased than that in the untransfected group.MTT assay showed that the proliferation capability of ACHN cells in the transfected and untransfected groups had no significant differences at different time points （P＆gt;0.05）.The expression of p-PDGFR-βin VSMC was significantly increased when cultured with PDGF-B overexpression culture medium. The mean tumor size of the PDGF-B group and control group was （0.305 ±0.108） cm3 and （0.577 ± 0.218） cm3, respectively （P =0.007）.Ki-67-positive tumor cells were （41.00 ±5.34）/HPF in the PDGF-B-transfected group and （ 5 5 .8 0 ±2 .9 5 ）/HPF in the untransfected group （ P=0 .0 0 1 ） .Conclusion PDGF-B overexpression may up-regulate p-PDGFR-βexpression of VSMC in renal cell carcinoma, and inhibit the tumor cell proliferation and tumor growth through paracrine signaling.