Yin-Hua Wang

Serum microRNAs are promising novel biomarkers for diffuse large B cell lymphoma

MicroRNAs (miRNAs) are regulatory RNA molecules that are deregulated in many disease types, including cancer. Recently, miRNAs have shown promise as markers for cancer diagnosis. The aim of this study was to investigate whether serum miRNAs can be used as biomarkers for the detection of diffuse large B cell lymphoma (DLBCL). We measured the levels of miRNAs (miR-15a, miR-16-1, miR-21, miR-29c, miR-34a, miR-155, and miR-223) in serum samples from patients with DLBCL and healthy controls using real-time quantitative reverse-transcription polymerase chain reaction (qRT-PCR). We show here that miRNAs are present in human serum in a remarkably stable form. Four of miRNAs (miR-15a, miR-16-1, miR-29c, and miR-155) were significantly elevated in DLBCL serum when compared with normal controls (P < 0.05), while miR-34a was downregulated in DLBCL serum when compared with controls (P < 0.05). Receiver operating characteristic analyses reflects strong discriminating DLBCL from controls, with area under the curves of 0.7722, 0.7002, 0.6672, 0.8538, and 0.7157 for miR-15a, miR-16-1, miR-29c, miR-34a, and miR-155, respectively. At the cut-off value of 0.0006 for miR-15a, the sensitivity was 80% and the specificity was 76%; at the cut-off value of 0.0886 for miR-16-1, the sensitivity was 94% and the specificity was 51%; at the cut-off value of 1.395 for miR-34a, the sensitivity was 100% and the specificity was 70%; at the cut-off value of 0.0022 for miR-155, the sensitivity was 83% and the specificity was 65%. In conclusion, these data suggest that serum miRNAs are potentially useful tools as novel noninvasive biomarker for the diagnosis of DLBCL.

Downregulated Dicer expression predicts poor prognosis in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common leukemia in the western world. Alterations in microRNAs (miRNAs) expression have been proposed to play a role in CLL pathogenesis. Dicer and Drosha are the main regulators of miRNA biogenesis, and deregulation of their expression has been indicated as a possible cause of miRNA alterations observed in various cancers. To investigate the role of Dicer and Drosha in CLL, we assessed the expression of Dicer and Drosha and their correlation with other prognostic factors, including Binet stages, immunoglobulin heavy chain variable gene (IGHV) mutation status, TP53 mutation status, ZAP‐70 protein and CD38 expression level in 165 CLL patients by using real‐time polymerase chain reaction methods. Patients with unmutated IGHV genes had significantly lower expression of Dicer than patients with IGHV mutations. The lower expression level of Dicer was also significantly associated with higher level of CD38 and ZAP‐70, and more aggressive Binet stage. We also analyzed Dicer expression in different cytogenetic subgroups. Lower Dicer level was found in patients with unfavorable cytogenetic aberrations (deletion in 17p13 or 11q22.3) in contrast to higher level in good risk cytogenetics (deletion in 13q14 as the sole abnormality). Furthermore, the lower expression of Dicer in CLL shows a strong association with shorter overall survival (OS) (P = 0.0046) as well as with reduced treatment free survival (TFS) (P = 0.0006). By contrast, no differences in the expression of Drosha among these groups of patients were observed. Our data suggest that Dicer expression may play an important role in the progression and prognosis of CLL. (Cancer Sci 2012; 103: 875–881)

Expression levels of Lyn, Syk, PLCγ2 and ERK in patients with chronic lymphocytic leukemia, and higher levels of Lyn are associated with a shorter treatment-free survival

Abstract There is now strong evidence that B-cell receptor (BCR) signaling plays a major role in the development of chronic lymphocytic leukemia (CLL). The purpose of this study was to investigate the expression levels of some of the molecules involved in the signaling cascade originating from the BCR (Syk, Lyn, PLCγ2, ERK) and analyze possible correlations of mRNA levels with biological/clinical features. Our study population consisted of 92 consecutive patients with newly diagnosed CLL. Several genes of BCR signaling (Lyn, Syk, PLCγ2 and ERK) and ZAP-70 were measured by quantitative polymerase chain reaction (qPCR). The signaling molecules of BCR were strongly associated with each other, and ZAP-70 correlated well with Lyn, Syk, PLCγ2 and ERK. Associations between treatment response and Lyn, Syk, PLCγ2 and ERK were not found. Moreover, a higher level of Lyn mRNA was associated with a shorter treatment-free survival (TFS) (univariate analysis only; multivariate Cox analysis showed that only ZAP-70 and Binet stage were independent prognostic factors and associated with TFS). Though Lyn was not an independent prognostic factor, it still might be a new therapy target of CLL. BCR signaling provides perspectives for future development of an exciting new class of kinase inhibitors.

The expression of SOX11, cyclin D1, cyclin D2, and cyclin D3 in B-cell lymphocytic proliferative diseases

SOX11 is mainly correlated with embryo neurogenesis and remodeling of tissues. D cyclins (cyclin D1, cyclin D2, and cyclin D3) work in cell transformation. We assessed the expression of SOX11, cyclin D1, cyclin D2, and cyclin D3 mRNA in 152 patients with B-cell lymphocytic proliferative diseases (B-LPD) using qRT-PCR and we detected SOX11 protein using immunohistochemistry in 15 B-LPD patients, to clarify the clinical significance of the four genes in B-LPD. Data showed the transcriptional levels of SOX11 and cyclin D1 were higher for the mantle cell lymphoma (MCL) samples compared with chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL), hairy cell leukemia (HCL), splenic marginal zone lymphoma (SMZL), and healthy collators. The expression levels of cyclin D1 and cyclin D2 were both higher in DLBCL than in SMZL. The expression levels of the four genes were highly related to each other. Three of 4 MCL patients showed nuclear staining for SOX11, while other 11 B-LPD examples were negative. Furthermore, we also found the ZAP70-positive CLL patients had higher SOX11 expression levels than ZAP70-negative CLL patients. It was revealed that MCL patients have higher expression levels of SOX11 and cyclin D1 mRNA, specially expressed nuclear SOX11 protein.

Richter transformation in 16 of 149 Chinese patients with chronic lymphocytic leukemia.

Abstract No confirmed risk factors are known to predict Richter syndrome (RS), and the value of clinical prognosticators conventionally applied to chronic lymphocytic leukemia (CLL) is not firmly established in this setting. The objective of this study was to present evidence for RS in Chinese patients with CLL and risk factors for CLL transformation to Richter syndrome. With a median follow-up of 43 months from CLL diagnosis in 149 Chinese patients, 16 (10.7%) patients progressed to diffuse large B-cell lymphoma (DLBCL). According to correlation analysis, a high level of lactate dehydrogenase (LDH) and CD38 positivity were found to be independent predictors of transformation to RS. Survival analysis showed that presence of RS, advanced Binet stage, high level of LDH, high level of β2-microglobulin, high concentration of thymidine kinase (TK), ZAP-70 and CD38 expression, unmutated immunoglobulin heavy chain variable (IGHV) gene status and del(17p13) were adverse factors in determining overall survival (OS). Only del(17p13) was strongly associated with survival by multivariate Cox regression analysis. Median OS after transformation was 16 months (95% confidence interval, 5.6–26.4 months). The results support that RS is associated with a poor outcome, and a policy of close monitoring and careful biopsy is needed in patients carrying transformation risk factors.

Prognostic significance of serum immunoglobulin paraprotein in patients with chronic lymphocytic leukemia.

The aim of this study was to explore the clinical and other associated laboratory features of chronic lymphocytic leukemia (CLL) patients with immunoglobulin (Ig) paraproteinemia. Serum protein electrophoresis (SPE) and immunofixation electrophoresis (IFE) were performed to measure serum Ig paraprotein. The correlations between serum Ig paraprotein and other prognostic factors were analyzed. Univariate and multivariate Cox regression analyses were used to assess associations between survival time and potential risk factors. In 133 Chinese CLL patients, 27 (20.3%) patients occurred Ig paraproteinemia at diagnosis. According to the correlation analysis, advanced Binet stage (r=0.314, P<0.001), direct antiglobulin test (DAT)-positive (r=0.366, P<0.001), high level of serum β2-microglobulin (β2-MG) (r=0.296, P=0.001) and thymidine kinase (TK) 1 (r=0.227, P=0.037), unmutated immunoglobulin heavy chain variable gene (IGHV) status (r=0.284, P=0.002), ZAP-70-positive (r=0.305, P=0.001), CD38-positive (r=0.284, P=0.002), and cytogenetic abnormalities of del(17p13) or del(11q22.3) (r=0.208, P=0.032) emerged as factors significantly related to the occurrence of Ig paraproteinemia. Survival analysis showed that the patients with Ig paraproteinemia had significantly shorter survival times than the patients without serum Ig paraprotein (P=0.013). Binet stage (P=0.028), high levels of lactate dehydrogenase (LDH) (P=0.004), IgG paraproteinemia (P=0.048), IgM paraproteinemia (P=0.001), ZAP-70-positive (P=0.003), DAT-positive (P=0.013), unmutated IGHV status (P=0.009), and del(17p13) (P=0.001) were the adverse factors in determining overall survival (OS). Del(17p13) (P=0.006), ZAP-70 (P=0.030), and IgM paraproteinemia (P=0.040) were the variables strongly associated with OS by multivariate Cox regression analysis. It was showed that serum Ig paraprotein might be applied for the assessment of prognosis in patients with CLL.

TP53 mutation is not an independent prognostic factor in patients with mantle cell lymphoma at advanced stage

Mantle cell lymphoma (MCL) is incurable in most patients. Several molecular markers have been identified as possible prognostic factors in MCL, including TP53 mutations. Direct sequencing was used to detect 32 cases with leukemic presentation of MCL form exons 2–11 in order to explore the prognostic significance of TP53 mutations in Chinese patients. Within the MCL cohort, 6(18.8%) patients harbored TP53 mutations. TP53 mutations in the absence of del(17p13) were found in 5.0% of MCL cases (1 of 20) compared with 83.3% of MCL cases (5 of 6) with del(17p13). Compared with patients without TP53 mutations, TP53 mutations were associated with risk factors including age, higher serum lactate dehydrogenase, lymphocytosis, high-risk (HR) international prognostic index, HR mantle cell lymphoma international prognostic index, complex karyotype, and higher occurrence of TP53 deletions. In contrast, it is found that TP53 mutations were correlated with mutated immunoglobulin heavy-chain variable region status and CD38 negative. TP53 mutations were the significant factors in predicting survival in univariate analysis, but unfortunately they were not the unique variable associated with overall survival by multivariate Cox regression analysis. TP53 mutation was insufficiently an independent prognostic factor in patients with MCL at advanced stage.