Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Oral Surg Oral Med Oral Pathol Oral Radiol. 2013 Mar;115(3):359-67. doi: 10.1016/j.oooo.2012.11.015.
To investigate HRPT2 in jaw ossifying fibroma (OF), fibrous dysplasia (FD), and osteosarcoma (OS).
We combined microsatellite loss of heterozygosity (LOH), HRPT2 sequence alterations at the mRNA level by reverse-transcription polymerase chain reaction (PCR), cDNA sequencing, and quantitative PCR (qPCR) and immunohistochemistry (IHC) in a total of 19 OF, 15 FD, and 9 OS. Because HRPT2 (parafibromin) interacts with cyclin D1, we investigated cyclin D1 expression with the use of qPCR and IHC.
LOH was detected in 3/5 FD, 6/9 OF, and 2/2 OS heterozygous samples. LOH was not associated with decreased mRNA levels or HRPT2 protein expression except for 1 OF which harbored an inactivating mutation. However, this tumor did not display altered transcription or protein levels of HRPT2 nor cyclin compared with the other OF.
The contribution of HRPT2 inactivation to the pathogenesis of OF, FD, and OS is marginal at best and may be limited to progression rather than tumor initiation.
研究颌骨骨化性纤维瘤(OF)、纤维结构不良(FD)和骨肉瘤(OS)中 HRPT2 的情况。
我们将微卫星杂合性缺失(LOH)、逆转录聚合酶链反应(PCR)检测 HRPT2 mRNA 水平的序列改变、cDNA 测序、实时定量 PCR(qPCR)和免疫组织化学(IHC)相结合,共检测了 19 例 OF、15 例 FD 和 9 例 OS。由于 HRPT2(副甲状腺素瘤基因)与细胞周期蛋白 D1 相互作用,我们还使用 qPCR 和 IHC 研究了细胞周期蛋白 D1 的表达。
LOH 检测到 3/5 FD、6/9 OF 和 2/2 OS 杂合样本中存在。除了 1 例 OF 存在失活突变外,LOH 与 mRNA 水平降低或 HRPT2 蛋白表达降低无关。然而,与其他 OF 相比,该肿瘤的 HRPT2 或 cyclin 转录或蛋白水平并未发生改变。
HRPT2 失活对 OF、FD 和 OS 的发病机制的贡献微乎其微,最多可能仅限于进展而不是肿瘤起始。