Wikström P, Bergh A, Damber J E
Department of Pathology, Umeå University, Sweden.
Urol Res. 1997;25(2):103-11. doi: 10.1007/BF01037924.
In the normal prostate, transforming growth factor-beta 1 (TGF-beta 1) inhibits epithelial cell growth and is associated with apoptosis. The role of TGF-beta 1 in prostate cancer remains, however, unclear. In this work, the expression of TGF-beta receptor type I and II (TGF beta-RI and TGF beta-RII) in the Dunning R3327 PAP adenocarcinoma was studied, after castration and oestrogen treatment. Since castration induces apoptosis in the rat ventral prostate (VP) [21], but not in the Dunning R3327 PAP tumour [46], the TGF-beta receptor levels in the tumour were compared to the receptor levels in the VP. Methods used were competitive reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. In the VP, TGF beta-RI and TGF beta-RII expressions were increased after castration, indicating a negative regulation of TGF beta receptors by androgens. In the Dunning tumour, TGF beta-RI and TGF beta-RII levels were elevated and only TGF beta-RI showed a clear-cut increase after castration. The receptors were located in epithelial and smooth muscle cells in the VP and mainly in epithelial cells in the Dunning tumour. In conclusion, the elevated TGF beta receptor levels and the diminished androgen regulation of TGF beta-RII in the tumour distinguish the Dunning R3327 PAP tumour from the normal prostate and need to be further elucidated.
在正常前列腺中，转化生长因子-β1（TGF-β1）抑制上皮细胞生长并与细胞凋亡相关。然而，TGF-β1在前列腺癌中的作用仍不清楚。在这项研究中，对去势和雌激素治疗后的邓宁R3327 PAP腺癌中I型和II型TGF-β受体（TGFβ-RI和TGFβ-RII）的表达进行了研究。由于去势可诱导大鼠腹侧前列腺（VP）发生细胞凋亡[21]，但对邓宁R3327 PAP肿瘤却无此作用[46]，因此将肿瘤中的TGF-β受体水平与VP中的受体水平进行了比较。所采用的方法为竞争性逆转录-聚合酶链反应（RT-PCR）和免疫组织化学。在VP中，去势后TGFβ-RI和TGFβ-RII的表达增加，表明雄激素对TGF-β受体具有负调控作用。在邓宁肿瘤中，TGFβ-RI和TGFβ-RII水平升高，且仅TGFβ-RI在去势后出现明显增加。这些受体位于VP的上皮细胞和平滑肌细胞中，而在邓宁肿瘤中主要位于上皮细胞中。总之，肿瘤中TGF-β受体水平升高以及TGFβ-RII的雄激素调节作用减弱，这使得邓宁R3327 PAP肿瘤有别于正常前列腺，对此还需要进一步阐明。
