High throughput quantitative reverse transcription PCR assays revealing over‐expression of cancer testis antigen genes in multiple myeloma stem cell‐like side population cells

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108270/1/bjh12951.pd

Automatic B cell lymphoma detection using flow cytometry data

Background: Flow cytometry has been widely used for the diagnosis of various hematopoietic diseases. Although there have been advances in the number of biomarkers that can be analyzed simultaneously and technologies that enable fast performance, the diagnostic data are still interpreted by a manual gating strategy. The process is labor-intensive, time-consuming, and subject to human error. Results: We used 80 sets of flow cytometry data from 44 healthy donors, 21 patients with chronic lymphocytic leukemia (CLL), and 15 patients with follicular lymphoma (FL). Approximately 15% of data from each group were used to build the profiles. Our approach was able to successfully identify 36/37 healthy donor cases, 18/18 CLL cases, and 12/13 FL cases. Conclusions: This proof-of-concept study demonstrated that an automated diagnosis of CLL and FL can be obtained by examining the cell capture rates of a test case using the computational method based on the multi-profile detection algorithm. The testing phase of our system is efficient and can facilitate diagnosis of B-lymphocyte neoplasms

Clinical Significance of PTEN Deletion, Mutation, and Loss of PTEN Expression in De Novo Diffuse Large B-Cell Lymphoma

PTEN loss has been associated with poorer prognosis in many solid tumors. However, such investigation in lymphomas is limited. In this study, PTEN cytoplasmic and nuclear expression, PTEN gene deletion, and PTEN mutations were evaluated in two independent cohorts of diffuse large B-cell lymphoma (DLBCL). Cytoplasmic PTEN expression was found in approximately 67% of total 747 DLBCL cases, more frequently in the activated B-cell-like subtype. Nuclear PTEN expression was less frequent and at lower levels, which significantly correlated with higher PTEN mRNA expression. Remarkably, loss of PTEN protein expression was associated with poorer survival only in DLBCL with AKT hyperactivation. In contrast, high PTEN expression was associated with Myc expression and poorer survival in cases without abnormal AKT activation. Genetic and epigenetic mechanisms for loss of PTEN expression were investigated. PTEN deletions (mostly heterozygous) were detected in 11.3% of DLBCL, and showed opposite prognostic effects in patients with AKT hyperactivation and in MYC rearranged DLBCL patients. PTEN mutations, detected in 10.6% of patients, were associated with upregulation of genes involved in central nervous system function, metabolism, and AKT/mTOR signaling regulation. Loss of PTEN cytoplasmic expression was also associated with TP53 mutations, higher PTEN-targeting microRNA expression, and lower PD-L1 expression. Remarkably, low PTEN mRNA expression was associated with down-regulation of a group of genes involved in immune responses and B-cell development/differentiation, and poorer survival in DLBCL independent of AKT activation. Collectively, multi-levels of PTEN abnormalities and dysregulation may play important roles in PTEN expression and loss, and that loss of PTEN tumor-suppressor function contributes to the poor survival of DLBCL patients with AKT hyperactivation

p63 expression confers significantly better survival outcomes in high-risk diffuse large B-cell lymphoma and demonstrates p53-like and p53-independent tumor suppressor function

The role of p53 family member, p63 in oncogenesis is the subject of controversy. Limited research has been done on the clinical implications of p63 expression in diffuse large B-cell lymphoma (DLBCL). In this study, we assessed p63 expression in de novo DLBCL samples (n=795) by immunohistochemistry with a pan-p63-monoclonal antibody and correlated it with other clinicopathologic factors and clinical outcomes. p63 expression was observed in 42.5% of DLBCL, did not correlate with p53 levels, but correlated with p21, MDM2, p16INK4A, Ki-67, Bcl-6, IRF4/MUM-1 and CD30 expression, REL gains, and BCL6 translocation. p63 was an independent favorable prognostic factor in DLBCL, which was most significant in patients with International Prognostic Index (IPI) >2, and in activated-B-cell–like DLBCL patients with wide-type TP53. The prognostic impact in germinal-center-B-cell–like DLBCL was not apparent, which was likely due to the association of p63 expression with high-risk IPI, and potential presence of ∆Np63 isoform in TP63 rearranged patients (a mere speculation). Gene expression profiling suggested that p63 has both overlapping and distinct functions compared with p53, and that p63 and mutated p53 antagonize each other. In summary, p63 has p53-like and p53-independent functions and favorable prognostic impact, however this protective effect can be abolished by TP53 mutations

Erratum: Clinical and biological significance of de novo CD5+ diffuse large B-cell lymphoma in Western countries

CD5 is a pan-T-cell surface marker and is rarely expressed in diffuse large B-cell lymphoma (DLBCL). Large-scale studies of de novo CD5+ DLBCL are lacking in Western countries. In this study by the DLBCL Rituximab-CHOP Consortium, CD5 was expressed in 5.5% of 879 DLBCL patients from Western countries. CD5+ DLBCL was associated with higher frequencies of >1 ECOG performance status, bone marrow involvement, central nervous system relapse, activated B-cell–like subtype, Bcl-2 overexpression, and STAT3 and NF-κB activation, whereas rarely expressed single-stranded DNA-binding protein 2 (SSBP2), CD30 or had MYC mutations. With standard R-CHOP chemotherapy, CD5+ DLBCL patients had significantly worse overall survival (median, 25.3 months vs. not reached, P< .0001) and progression-free survival (median, 21.3 vs. 85.8 months, P< .0001) than CD5− DLBCL patients, which was independent of Bcl-2, STAT3, NF-κB and the International Prognostic Index. Interestingly, SSBP2 expression abolished the prognostic significance of CD5 expression, suggesting a tumor-suppressor role of SSBP2 for CD5 signaling. Gene-expression profiling demonstrated that B-cell receptor signaling dysfunction and microenvironment alterations are the important mechanisms underlying the clinical impact of CD5 expression. This study shows the distinctive clinical and biological features of CD5+ DLBCL patients in Western countries and underscores important pathways with therapeutic implications