Research progress on prognostic markers of chronic lymphocytic leukemia / 浙江大学学报·医学版

Chronic lymphocytic leukemia (CLL) remains the most common adult leukemia. The recent progress on research of molecular and cellular genetics of CLL promotes the development of the diagnosis, treatment and prognosis for CLL patients. IGVH gene mutation status is the most important prognostic marker for CLL patients. Zeta-chain-associated protein kinase (ZAP-70) can be used as a surrogate marker for IGVH mutation status. CD38 is a type II transmembrane glycoprotein promoting B cell activation and proliferation, which can improve the survival of CLL cells and enhance their proliferation, so it also can be used as an independent prognostic indicator for CLL. Chromosome aberrations are found in more than 80% of CLL cases. The most frequent abnormalities are losses of chromosomal material, with deletions in band 13q14 being the most common. The most common gains of chromosomal material are trisomies 12q. Human leukocyte antigen G (HLA-G) is a non-classical HLA-I gene. Increased expression of HLA-G leads to the malignant progression of CLL, significantly shortens survival, indicating HLA-G might serve as a prognostic marker in CLL. Toll-like receptors (TLA) are important component of natural immunity. The combination of TLR agonists and release chemotherapy, monoclonal antibodies and tumor vaccines would bring a breakthrough for the treatment of CLL.

Clonality analysis and mutation status of IgVH genes in classic Richter's syndrome / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clonal rearrangements and mutation status of IgVH genes in classic Richter's syndrome, the relationship between molecular findings of IgVH gene and clinical outcome, and to deciper the possible molecular mechanism of transformation.</p><p><b>METHODS</b>The clonal rearrangements and mutation status of IgVH genes were analyzed in cases of classic Richter's syndrome by Genescan and sequencing. Immunohistochemical study for zeta-chain associated protein kinase 70 kDa (ZAP70), p53 and interferon regulation factor 4 (IRF-4) was also performed.</p><p><b>RESULTS</b>Samples of 18 cases of B-chronic lymphocytic leukemia (B-CLL)/ diffuse large B-cell lymphoma (DLBCL,78. 3%) had identical tumor cell clones, whereas DLBCL developed as a clonally independent neoplasm in 5 patients (21.7%). Among the clonally related group, 12 cases carried unmutated VH genes in both B-CLL and DLBCL components and VH3-23, VH3-74 and VH1-2 were accounted for the B-CLL transformation to DLBCL. Immunohistochemical study showed that the transformed DLBCL expressed CD5 in 32.1% of cases, CD23 in 14.3%, ZAP70 in 23.8%, p53 in 80.6% and IRF-4 in 82.6% of the cases respectively. Follow-up data were available in 17 patients with classic Richter's syndrome. The median survival period was 7 months. No significant difference in survival rate was obtained between the clonally related or unrelated groups, between IgVH gene mutated or unmutated groups, and between the groups with or without expression of ZAP70, p53 and IRF-4.</p><p><b>CONCLUSIONS</b>The ratio of clonally related transformed DLBCL from B-CLL to clonally unrelated DLBCL is 2:1. Clonal transformation to DLBCL predominantly occurs in B-CLL patients carrying unmutated IgVH genes. The biased IgVH gene usage suggests antigens are involved in classic Richter's syndrome. Molecular differences of IgVH genes and very poor clinical outcome of this group of transformed DLBCL indicate that there cases may be regarded as a distinct subset of DLBCL.</p>

Clonality analysis and mutational status of IgVH gene in Hodgkin variant of Richter syndrome / 中华病理学杂志

<p><b>OBJECTIVE</b>To detect the clonal relationship, the rearrangement, and the mutational status of IgVH gene; the influence of these molecular characteristics on the clinical outcome in Hodgkin variant of Richter syndrome; and the possible molecular pathogenesis in this transformation.</p><p><b>METHODS</b>The clonal rearrangements and mutational status of IgVH genes were analyzed in Hodgkin variant of Richter syndrome and B-CLL with Reed-Stemberg (R-S)-like cells by GeneScan analysis and sequencing. Semi-nest PCR based on laser capture microdissection was utilized to compare the clonal relationship between B-CLL and R-S/R-Slike cells. Immunohistochemical staining was used to detect the different expressions of ZAP70, p53, IRF-4 and LMP1 in the two components.</p><p><b>RESULTS</b>(1) 5/6 B-CLL cases transformed to Hodgkin lymphoma (HL)/R-S-like cells carried the mutated IgVH genes; (2) 2 cases of R-S cells and 1 case of R-S-like cells were clonally distinct from B-CLL clone and express LMP1, whereas 1 case of R-S-like cells was relating to the surrounding B-CLL cells and did not express LMP1; (3) 2/6 B-CLL cases transformed to HL convey VH4-34 and VH3-48 respectively.</p><p><b>CONCLUSIONS</b>(1) Richter transformation to HL/R-S-like cells evolves from the B-CLL which originates from the germinal center or post germinal center B cells, indicating that different lymphoma cells of different subtypes in Richter syndrome come from different B cell lineage and possibly involve a different pathogenesis and pathway; (2) HL and R-S-like cells evolve from either the B-CLL clone or may develop as a clonally unrelated lymphoma, the independent secondary malignancies are appear to be EBV-positive, possibly as a consequence of the underlying immunodeficiency; (3) The biased usage of IgVH genes suggested a role of antigens involved in the HL variant of Richter syndrome.</p>

A novel microsatellite within intron 8 in caspase10 gene in Chinese of Han nationality / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate polymorphisms in the coding exons and their splicing areas of caspase10 gene (CASP10) in Chinese of Han nationality.</p><p><b>METHODS</b>Polymerase chain reaction (PCR), denaturing high-performance liquid chromatography (DHPLC), direct sequencing and clonal sequencing were used to analyze the exon 9 and its flanking sequences.</p><p><b>RESULTS</b>In 70 blood samples of Chinese subjects researched the known single nucleotide polymorphisms (SNPs) in the exon 9 of CASP10 gene published in dbSNP of NCBI were not identified. We found a short sequence with more than ten continuous and repeated T nucleotides within the intron 8 near the exon 9 and the length of repeated sequence nucleotides T was different in samples. Clonal sequencing analysis indicated that it was a microsatellite of single nucleotide-repeated sequence. The recurrence and specificity of same result was further confirmed by PCR with high fidelity polymerase and sequencing. Furthermore all of 70 blood samples detected by DHPLC showed heterozygous profiles. We named it as IVS8-13(T)n temperately.</p><p><b>CONCLUSION</b>Our research suggested that the site be a microsatellite of single nucleotide-repeated sequence. Meanwhile, our data further showed that it was quite different from that by querying SNP database of non-Chinese population in NCBI, in the same region a SNP of type of insertion deletion existed. It could be inferred that the difference between the populations might be associated with the genetic characteristics of ethnics. The significance of the microsatellite in CASP10 gene in Chinese of Han nationality remains to be elucidated.</p>

BCL-2/IgH translocation in peripheral blood cells of healthy Chinese individuals of Han nationality located in Zhejiang area / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the frequency of BCL-2/IgH rearrangement in peripheral blood cells of healthy Chinese individuals of Han nationality located in Zhejiang area and the low incidence of follicular lymphoma (FL).</p><p><b>METHODS</b>Nested-PCR and direct DNA sequencing were used to detect the Bcl-2/IgH rearrangement in peripheral blood cells of 196 healthy individuals. DNA sequences involved were then searched and aligned in NCBI database to confine the broken points in major breakpoint region and the IgH segments involved.</p><p><b>RESULTS</b>First, in this sample the frequency of BCL-2/IgH translocation in Chinese individuals of Han nationality located in Zhejiang area is 9.66%, being much lower than that in North America and Europe countries. Second, the breakpoints tend to fall into 3 clusters: 3055, 3116 and 3165 bp. Usage of J6 segment is most common. Third, There are different subclones of BCL-2/IgH rearrangements in the same individual.</p><p><b>CONCLUSION</b>The low frequency of BCL-2/IgH translocation in healthy Chinese individuals of Han nationality located in Zhejiang area may be one of the reasons for the difference in the incidence of FL between China and Western countries.</p>

Study of dual rearrangements of lymphocytic antigen receptor genes in non-Hodgkin lymphoma / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the rate of dual rearrangements of lymphocytic antigen receptor genes in non-Hodgkin lymphomas (NHL) and its pathogenesis and pathologic significance.</p><p><b>METHODS</b>PCR analysis of monoclonal, polyclonal and dual rearrangements of IgH and TCR gamma, TCR beta genes was carried out in 125 cases of NHL to evaluate the rate of dual rearrangements, immunohistochemistry was performed for a Ki67 protein expression in 117 cases and the proliferation index was calculated. The relationship between antigen receptor gene rearrangements and proliferation index was analyzed.</p><p><b>RESULTS</b>Combination of the two pairs of IgH gene primers with the multiplex PCR for TCR gamma and TCR beta gene revealed dual rearrangements in 8% (8/96) of B-NHL, 17% (5/29) of T-NHL. In B cell NHL, IgH gene monoclonal, dural and polyclonal rearrangements were identified in 65, 8 and 15 cases respectively, while in T-cell NHL, they were in 15, 5 and 9 cases, respectively. There was no significant difference between proliferation index and monoclonal, dual, polyclonal rearrangements in both B-NHL and T-NHL by One-way test.</p><p><b>CONCLUSION</b>Dual rearrangements in NHL are not rare and have no relationship with proliferation index.</p>

Detection of IgH gene rearrangement in B-cell non-Hodgkin's lymphoma and application of gel-scan method / 中华病理学杂志

<p><b>OBJECTIVE</b>To develop a protocol for gene rearrangement study in non-Hodgkin's lymphoma (NHL) by PCR-directed gel-scan method and to set up quantitative criteria for IgH gene rearrangement which can be applied in the follow up of lymphoma patients.</p><p><b>METHODS</b>IgH gene rearrangement studies were carried out in 96 cases of B-cell NHL. The detection rate of clonality was evaluated. Sixty-five cases of IgH gene rearranged cases proven by FR3A-directed PCR and PAGE and 8 cases of benign lymphoid tissues (5 cases of reactive lymphoid hyperplasia, 3 cases of chronic tonsillitis), 5 cases of normal peripheral blood mononuclear cells were analyzed by gel-scan method and the proportion of h1/h2 (heights of peak1 and peak2 of gel-scan) was calculated.</p><p><b>RESULTS</b>The detection rate of IgH gene clonality was up to 68% using primer FR3A in the 96 B-cell NHL cases. The detection rate was up to 61% using primer FR2A. With a combination of primers FR3A and FR2A, the detection rate increased to 83%. Gel-scan curve showed that the value of h1/h2 was greater than 3 in all the 65 cases with IgH gene rearranged. In the 8 benign lymphoid tissue cases showed h1/h2 < 1.5, 5 cases with normal peripheral blood mononuclear cells showed a bell-shaped curve.</p><p><b>CONCLUSIONS</b>In the gel-scan curve of gene rearrangement studies in non-Hodgkin's lymphoma samples, the value of h1/h2 greater than 3 represents a true clonal proliferation. The peaks with relative heights less than 1.5 may not be significant and likely represent polyclonal cell population. A value between 1.5 and 3 however requires clinical follow-up. The success rate of rearrangement studies in B-cell NHL can be increased by using a combination of primers FR3A and FR2A.</p>