Establishment of aspiration biopsy RNA diagnosis of malignant lymphoma

区分甲状腺恶性淋巴瘤和淋巴细胞性甲状腺炎（桥本甲状腺炎）是相当困难和有问题的。基于免疫球蛋白重链（immunoglobulin heavy chain, IgH）基因重排的克隆性淋巴细胞增殖分子检测技术可能有助于更准确地诊断恶性淋巴瘤。我们试图建立一种通过分析细针穿刺活检针中提取的核酸来诊断甲状腺肿瘤的方法。我们首先对8例桥本甲状腺炎和18例恶性淋巴瘤新鲜组织样本的rna进行半巢式rt - pcr检测其单克隆性。18例恶性甲状腺瘤中有8例（44.4%）检测到单克隆，而桥本甲状腺炎8例中无单克隆。我们研究了10例甲状腺恶性淋巴瘤、4例桥本甲状腺炎、腺瘤性甲状腺肿和乳头状癌各1例的抽吸液。10例恶性淋巴瘤中有4例（40%）的抽吸液检测到单克隆，但其他组织中未检测到单克隆。因此，在血清学检查的基础上，RT-PCR检测IgH mRNA单克隆可能有助于甲状腺恶性淋巴瘤的诊断。为了提高这种方法的灵敏度，我们研究了退化寡核苷酸引物（OOP） PCR在细针穿刺活检中扩增提取dna的有效性。通过混合JH序列特异性引物，dopp -PCR可得到3-10kbp的PCR产物，可用于连接链PCR或Southern blot分析。这些结果可能会引导我们在未来的研究中利用dna代替细针穿刺活检获得的rna来建立恶性淋巴瘤的低创诊断方法

Distinguishing between thyroid malignant lymphoma and lymphocytic thyroiditis (Hashimoto's tbyroiditis) is 'quite difficult and problematic. Molecular techniques to detect clonal lymphoid proliferation based on immunoglobulin heavy chain (IgH) gene rearrangement may be used to facilitate more accurate diagnosis of malignant lymphoma. We tried to establish a method for diagnosing thyroid tumors by analyzing nucleic acids extracted from the needles used for fine needle aspiration biopsy. We first studied RNAs from fresh tissues samples of 8 cases of Hashimoto's thyroiditis and 18 malignant lyrnphomas to detect the monoclonality of IgH mRNA by semi-nested R.T-PCR. Monoclonality was detected in 8 of 18 (44.4%) malignant ryrnphomas but none of the 8 cases of Hashimoto's thyroiditis. We then studied aspirates from 10 cases of thyroid malignant lymphoma, 4 cases of Hashimoto's thyroiditis, and one case each of adenomatous goiter and papillary carcinoma. Monoclonality was detected in the aspirates from 4 of 10 malignant lymphomas (40%) but not from other tissues. Thus RT-PCR detection of monoclonality of IgH mRNA in addition to eytological examination may be useful in diagnosing thyroid malignant lyraphoma. In order to increase the sensitivity of this method, we examine the usefulness of degenerated oligonucleotide primed (OOP) PCR to amplify the extracted DNAs in fine needle aspiration biopsies. By mixing a primer specific for the JH sequence, DOP-PCR could produce 3-10kbp PCR product, which could be used in linker-ligation PCR or Southern blot analysis. These results may lead us to establish a low-invasive diagnostic method of malignant lymphoma in the future study by utilizing DNAs instead of RNAs obtained by fine needle aspiration biopsy