微小RNA-301a介导高血糖对前列腺癌细胞裸鼠移植瘤的促生长作用

MicroRNA-301a mediates the growth of human prostate cancer cell xenografts in nude mice pro- moted by hyperglycaemia

目的观察微小RNA（miRNA，miR）-301a介导高血糖对人前列腺癌细胞PC3裸鼠移植瘤的促生长作用。方法以40mg／kg链脲佐菌素连续5d腹腔注射建立高血糖裸鼠模型，以慢病毒构建miR-301a过表达载体（LV-miR-301a）及其阴性对照，并构建miR-301a抑制剂载体（LV-miR-301a—inhibitor）及其阴性对照，转染PC3细胞，得到稳转细胞株。将上述稳转细胞（5×10 6个）分别接种到高血糖及正常糖裸鼠的皮下，成瘤后连续观察移植瘤的生长。5周后处死裸鼠，剥离瘤体组织，实时定量反转录聚合酶链反应（RT—qPCR）检测miR．301a的表达。结果接种空白PC3细胞后，高血糖组裸鼠瘤体组织miR-301a的表达量是正常组的（30．83±5．42）倍（P〈0．01），且前者最终瘤体体积[（850．46±72．54）mm3]明显比后者瘤体体积[（430．35±49．56）mm3]大（P〈0．01）。在正常组中，过表达miR-301a的移植瘤体积为（925．26±83．43）mm3，明显大于其阴性对照组瘤体（461．25±58．74）mm3（P〈0．01）。在高血糖组中，miR-301a抑制型移植瘤体积为（550．13±55．12）mm3显著小于其阴性对照组的（830．16±64．86）mm3（P〈0．01）。结论高血糖可以通过上调前列腺癌细胞miR-301a的表达，促进肿瘤生长，抑制miR-301a的表达，可以部分阻断高血糖对前列腺癌细胞的促生长作用。

Objective To investigate the effect of microRNA （miRNA, miR） -301a on the growth of human prostate cancer cell xenografts in nude mice promoted by hyperglycaemia. Methods The male BALB/c nude mice were treated with five consecutive daily intraperitoneal injections of streptozotocin （STZ, 40 mg/kg） to establish the hyperglycaemic nude mice model. Lentivirus vectors were used to con- struct the miR- 301a overexpression vectors （LV- miR- 301a） and the negative control, miR- 301a in- hibitor vectors （LV -miR- 301a- inhibitor） and the negative control. Human prostate cancer cells （ PC3, 5 ∽ 106 ） were infected by variours recombinant lentivirus to acquire stable transfection cells. The stable transfection cells were injected subcutaneously into both the hyperglycaemic and the normoglyceamic nude mice to establish the model of human prostate cancer cell xenografts. Tumor growth was monitored regularly for five weeks, and the tumor tissues were harvested from euthanized mice. RNA was isolated and the expression of miR- 301a was detected by real -time reverse transcriptase -polymerase chain reaction （ RT - qPCR）. Results For the blank PC3 - derived xenografs, the expression of miR - 301 a from the hy- perglycaemic mice was （30. 83 -± 5.42） times higher than that in the normoglyceamic mice （ P 〈 0. 01 ）. The tumor volume （850. 46 ± 72. 54） mm2 in hyperglycaemic group was significantly larger than that in the normoglyceamic group （430. 35 ± 49. 56） mm3 （ P 〈 0. 01 ） at the termination of the experiment. In the normoglyceamic nude mice, tumor volumes in the PC3 -miR -301 a group were （925.26 ± 83.43） mm3 , significantly larger than those in PC3 - miR - control group （461.25 ± 58.74） mm3 （ P 〈 0. 01 ）. In the hyperglycaemic nude mice, the tumor size （550. 13 ± 55.12） mm3 from PC3 -miR -301a -inhibitor xen- ografts was significantly smaller than PC3 - antimiR - NC tumors （ 830. 16 ± 64. 86 ） mm3 （ P 〈 0. 01 ）. Conclusion Hyperglycaemia can promote the prostate cancer cell xenografts in nude mice by up - regulating the expression of miR-301a. Inhibition of miR-301a can prevent the promoted effect of hyperglycaemia.