Sheth Neil, Yeung Joanna, Chang Hong
Department of Laboratory Hematology, University Health Network, Toronto, ON, Canada.
Leuk Res. 2009 Oct;33(10):1357-60. doi: 10.1016/j.leukres.2009.01.010. Epub 2009 Feb 8.
Progression of multiple myeloma (MM) from intramedullary to extramedullary sites heralds an aggressive phase of the disease but to the best of our knowledge, biologic factors have not been studied in paired biopsies from medullary and extramedullary sites. In this study, we immunostained paired bone marrow and extramedullary biopsies from 12 cases of MM for p53, CD56 and MIB-1 (proliferative index). In addition, 22 cases of extramedullary plasmacytoma (EMP) without bone marrow involvement were included as a control group. p53 nuclear accumulations were detected in myeloma cells derived from the extramedullary sites in 9 (75%) of the 12 cases, whereas only 1 of (8%) 12 bone marrow myeloma specimens expressed p53 (P = 0.003). p53 expression was also more prevalent in extramedullary sites of MM than EMP (75% vs. 18%, P = 0.003). There was no significant difference in CD56 expression between intramedullary and extramedullary MM (17% vs. 33%, P = 0.64), or between intramedullary MM and EMP (17% vs. 38%, P = 0.25). The MIB-1 proliferation index increased significantly as plasma cells migrated from the bone marrow microenvironment to extramedullary sites (P = 0.0001). Our data indicates that p53 nuclear expression but not CD56 expression, along with increased proliferation index is associated with disease progression from intramedullary to extramedullary sites in MM.
多发性骨髓瘤（MM）从髓内发展至髓外部位预示着疾病进入侵袭性阶段，但据我们所知，尚未对来自髓内和髓外部位的配对活检组织中的生物学因素进行研究。在本研究中，我们对12例MM患者的配对骨髓和髓外活检组织进行了p53、CD56和MIB-1（增殖指数）免疫染色。此外，纳入22例无骨髓受累的髓外浆细胞瘤（EMP）作为对照组。在12例患者中的9例（75%）髓外部位来源的骨髓瘤细胞中检测到p53核积聚，而12例骨髓骨髓瘤标本中仅有1例（8%）表达p53（P = 0.003）。p53表达在MM的髓外部位也比EMP更普遍（75%对18%，P = 0.003）。髓内和髓外MM之间的CD56表达无显著差异（17%对33%，P = 0.64），髓内MM和EMP之间也无显著差异（17%对38%，P = 0.25）。随着浆细胞从骨髓微环境迁移至髓外部位，MIB-1增殖指数显著增加（P = 0.0001）。我们的数据表明，p53核表达而非CD56表达，以及增殖指数增加与MM从髓内至髓外部位的疾病进展相关。
