Aliano Stefania, Cirmena Gabriella, Garuti Anna, Fugazza Giuseppina, Bruzzone Roberto, Rocco Ilaria, Malacarne Michela, Ballestrero Alberto, Sessarego Mario
Laboratory of Cytogenetics, Department of Internal Medicine, University of Genoa, V.le Benedetto XV-6, 16132 Genoa, Italy.
Cancer Genet Cytogenet. 2007 Sep;177(2):115-9. doi: 10.1016/j.cancergencyto.2007.05.009.
Chromosomal translocations involving the 12q14 band are rarely detected in hematological disorders, and are usually correlated with HMGA2 gene expression. HMGA2 is highly expressed during embryonic cell growth and differentiation, and regulates transcription and chromatin organization, but is rarely detectable in adult tissues. We describe a case of polycythemia vera with a t(12;21)(q14;q22). The 12q14 breakpoint was characterized by fluorescence in situ hybridization analysis using the bacterial artificial chromosome RP11-366L20 containing 3' sequences of the HMGA2 gene. Qualitative and quantitative polymerase chain reaction showed the presence of high levels of HMGA2 gene expression, which were temporarily reduced with hydroxyurea therapy. The present case confirms that involvement of the 12q14 band may be associated with HMGA2 overexpression in chronic Philadelphia chromosome-negative myeloproliferative disease, regardless of the partner chromosome involved in the translocation. Such overexpression may contribute to the pathogenesis of the disease, which otherwise of itself shows a favorable and stable course.
涉及12q14带的染色体易位在血液系统疾病中很少被检测到，并且通常与HMGA2基因表达相关。HMGA2在胚胎细胞生长和分化过程中高度表达，调节转录和染色质组织，但在成人组织中很少能检测到。我们描述了一例伴有t(12;21)(q14;q22)的真性红细胞增多症病例。使用包含HMGA2基因3'序列的细菌人工染色体RP11-366L20，通过荧光原位杂交分析对12q14断点进行了表征。定性和定量聚合酶链反应显示存在高水平的HMGA2基因表达，羟基脲治疗后其暂时降低。本病例证实，在慢性费城染色体阴性骨髓增殖性疾病中，无论易位涉及的伙伴染色体如何，12q1带的受累可能与HMGA2过表达相关。这种过表达可能促成该疾病的发病机制，否则该疾病本身表现出良好且稳定的病程。
