大鼠前列腺上皮细胞角蛋白8mRNA表达调节的定位研究

本文应用反义RNA探针原位杂交法,研究雄激素对大鼠腹侧前列腺(VP)上皮细胞角蛋白(CK)8 mRNA表达的影响。发现1.在任何VP组织切片中,CK 8探针专一、大量定位于VP腺上皮细胞中,CK 8 mRNA是前列腺上皮细胞特异而灵敏的标志。2.去睾大鼠VP CK 8 mRNA染色增强,提示CK 8mRNA有过度表达,注射雄激素又可抑制其过度表达。3.与已知受雄激素抑制性基因不同,即使大鼠VP完全萎缩之后达2个月之久,其存留腺上皮细胞CK 8 mRNA表达仍持续增高。4.前列腺发育早期,迅速增殖的幼稚腺上皮细胞高度表达CK 8 mRNA,以后随着体内雄激素水平升高,VP上皮CK 8 mRNA表达下降,分布转移。以上结果进一步支持前列腺CK 8基因是新的一类受雄激素抑制性基因的推测,同时表明前列腺CK 8基因的表达与前列腺干细胞的增殖分化有密切联系,CK 8 mRNA高度表达是前列腺干细胞一个重要特征。

LOCALIZATION AND REGULATION OF CYTOKERATIN 8 mRNA EXPRESSION IN RAT PROSTATE EPITHELIA

The effects of androgen on cytokera-tin (CK) 8 mRNA expression in rat ventral prostate (VP) were studied by in situ hybridization with an antisense RNA-pro-be. It was found that 1) the CK 8 anti-sense RNA-probe was accumulated only within prostatic epithelial cells, indicating that the CK 8 mRNA is a specific and sensitive marker for prostate epithelia. 2) After castration, the signals of CK 8 mRNA in VP sections were significantly increased. Administration of androgen to the castrated male host repressed the elevated expression of CK 8 mRNA in VP. This effect can be antagonized by the simultaneous administration of an antian-drogen. 3) Unlike other androge-repressed gene, the elevated expression of CK 8 mRNA in VP was persisted even 2 mon-ths after the process of glandular involution was completed. 4) During prostate development, the strongest CK 8 mRNA staining was found in the early neonatal prostatic epithelia which were composed mainly of prostatic stem cells. Thereafter, when the levels of serum androgen were gradualy increased, the shift of CK 8 mRNA staining to peripheral region and decreased level of overall CK 8 mRNA were noted. These data support the notion that the CK 8 gene of prostate epithelia is a new class of androgen-repressed one. The data also indicated that the expression of CK 8 gene is closely related with the proliferation and differentiation of prostate stem cells, and excessive expression of CK 8 mRNA is a characteristic for prostatic stem cells.