Kanno H, Yasunaga Y, Ohsawa M, Taniwaki M, Iuchi K, Naka N, Torikai K, Shimoyama M, Aozasa K
Departmemt of Pathology, Osaka University Medical School, Japan.
Int J Cancer. 1996 Jul 3;67(1):86-94. doi: 10.1002/(SICI)1097-0215(19960703)67:1<86::AID-IJC15>3.0.CO;2-A.
Malignant lymphomas frequently develop in the pleural cavity of patients with long-standing pyothorax. The term pyothorax-associated lymphoma (PAL) has been proposed for this type of tumor. Most PALs are diffuse lymphomas of the B-cell type and contain Epstein-Barr virus (EBV) DNA. We have established 2 lymphoma cell lines from biopsy specimens of PAL cases, OPL-1 and OPL-2, and examined their growth characteristics and the expression of EBV latent infection genes and oncogenes. OPL-2 exhibited a more rapid growth and higher saturation density than OPL-1, and only OPL-2 exhibited colony-forming activity in soft agar. OPL-1 and -2 were positive for B-cell differentiation markers and showed clonal surface immunoglobulins. Both line contained a single predominant form of episomal EBV DNA, indicating clonal cellular proliferation of an EBV-infected progenitor cell. OPL-1 and -2 contained type B and A EBV genome, respectively. Expression of EBV nuclear antigen (EBNA)2 mRNA and protein was detected by Northern and Western blot analysis in OPL-1, but not in OPL-2. On the other hand, the expression of latent membrane protein (LMP)1 mRNA in both OPL-1 and -2 was extremely weak and detectable only by reverse transcription-polymerase chain reaction. Protein expression of LMP1 was not observed by Western blot analysis or immunocytochemistry. Both lines expressed c-myc mRNA. Only OPL-1 expressed mRNA of c-fgr, an oncogene whose expression is upregulated by EBNA2. Both OPLs expressed bcl-2 mRNA without detectable expression of LMP1 protein.
恶性淋巴瘤常发生于长期脓胸患者的胸腔内。针对这类肿瘤，已提出“脓胸相关淋巴瘤（PAL）”这一术语。大多数PAL为B细胞型弥漫性淋巴瘤，且含有EB病毒（EBV）DNA。我们从PAL病例的活检标本中建立了2株淋巴瘤细胞系，即OPL - 1和OPL - 2，并检测了它们的生长特性以及EBV潜伏感染基因和癌基因的表达。与OPL - 1相比，OPL - 2生长更快且饱和密度更高，并且只有OPL - 2在软琼脂中表现出集落形成活性。OPL - 1和 - 2对B细胞分化标志物呈阳性，并显示出克隆性表面免疫球蛋白。两株细胞系均含有单一主要形式的游离型EBV DNA，表明EBV感染的祖细胞发生了克隆性细胞增殖。OPL - 1和 - 2分别含有B型和A型EBV基因组。通过Northern和Western印迹分析在OPL - 1中检测到EB病毒核抗原（EBNA）2 mRNA和蛋白，但在OPL - 2中未检测到。另一方面，OPL - 1和 - 2中潜伏膜蛋白（LMP）1 mRNA的表达都极其微弱，仅通过逆转录 - 聚合酶链反应才能检测到。通过Western印迹分析或免疫细胞化学未观察到LMP1蛋白的表达。两株细胞系均表达c - myc mRNA。只有OPL - 1表达c - fgr的mRNA，c - fgr是一种其表达受EBNA2上调的癌基因。两株OPL均表达bcl - 2 mRNA，但未检测到LMP1蛋白的表达。
