Gene expression profiling of non-hodgkin lymphomas

Identification of circRNA-lncRNA-miRNA-mRNA Competitive Endogenous RNA Network as Novel Prognostic Markers for Acute Myeloid Leukemia

Background: Acute myeloid leukemia (AML) is one of the most common malignant and aggressive hematologic tumors, and its pathogenesis is associated with abnormal post-transcriptional regulation. Unbalanced competitive endogenous RNA (ceRNA) promotes tumorigenesis and progression, and greatly contributes to tumor risk classification and prognosis. However, the comprehensive analysis of the circular RNA (circRNA)-long non-coding RNA (lncRNA)-miRNA-mRNA ceRNA network in the prognosis of AML is still rarely reported. Method: We obtained transcriptome data of AML and normal samples from The Cancer Genome Atlas (TCGA), Genotype-tissue Expression (GTEx), and Gene Expression Omnibus (GEO) databases, and identified differentially expressed (DE) mRNAs, lncRNAs, and circRNAs. Then, the targeting relationships among lncRNA-miRNA, circRNA-miRNA, and miRNA-mRNA were predicted, and the survival related hub mRNAs were further screened by univariate and multivariate Cox proportional hazard regression. Finally, the AML prognostic circRNA-lncRNA-miRNA-mRNA ceRNA regulatory network was established. Results: We identified prognostic 6 hub mRNAs (TM6SF1, ZMAT1, MANSC1, PYCARD, SLC38A1, and LRRC4) through Cox regression model, and divided the AML samples into high and low risk groups according to the risk score obtained by multivariate Cox regression. Survival analysis verified that the survival rate of the high-risk group was significantly reduced (p < 0.0001). The prognostic ceRNA network of 6 circRNAs, 32 lncRNAs, 8 miRNAs, and 6 mRNAs was established according to the targeting relationship between 6 hub mRNAs and other RNAs. Conclusion: In this study, ceRNA network jointly participated by circRNAs and lncRNAs was established for the first time. It comprehensively elucidated the post-transcriptional regulatory mechanism of AML, and identified novel AML prognostic biomarkers, which has important guiding significance for the clinical diagnosis, treatment, and further scientific research of AML.

Hematology oncology practice in the Asia-Pacific APHCON survey results from the 6th international hematologic malignancies conference: bridging the gap 2015, Beijing, China

This report serves as a snapshot of the state-of-knowledge in the Asia Pacific (APAC) Hematology Oncology community, and establishes a baseline for longitudinal investigations to follow changes in best practices over time. The objective of this study was to understand the approach to hematologic diseases, common standards of care and best practices, issues that remain controversial or debated, and educational or resource gaps that warrant attention. We used mobile application to disseminate and distribute questionnaires to delegates during the 6th international hematologic malignancies conference hosted by the APAC Hematology Consortium at Beijing, China. User responses were collected in an anonymous fashion. We report survey results in two ways: the overall responses, and responses as stratified between Chinese physicians and "Other" represented nationalities. Overall geographical concordance in survey responses was positive and strong. Perhaps more interesting than instances of absolute agreement, these data provide a unique opportunity to identify topics in which physician knowledge or opinions diverge. We assigned questions from all modules to broad categories of: patient information; diagnosis; treatment preference; transplantation; and general knowledge/opinion. On average, we observed a geographic difference of 15% for any particular answer choice, and this was fairly constant across survey modules. These results reveal utility and need for widespread and ongoing initiatives to assess knowledge and provide evidence-based education in real time. The data will be made more valuable by longitudinal participation, such that we can monitor changes in the state of the art over time.

Consensus reference gene(s) for gene expression studies in human cancers: end of the tunnel visible?

BACKGROUND

Gene expression studies are increasingly used to provide valuable information on the diagnosis and prognosis of human cancers. Also, for in vitro and in vivo experimental cancer models gene expression studies are widely used. The complex algorithms of differential gene expression analyses require normalization of data against a reference or normalizer gene, or a set of such genes. For this purpose, mostly invariant housekeeping genes are used. Unfortunately, however, there are no consensus (housekeeping) genes that serve as reference or normalizer for different human cancers. In fact, scientists have employed a wide range of reference genes across different types of cancer for normalization of gene expression data. As a consequence, comparisons of these data and/or data harmonizations are difficult to perform and challenging. In addition, an inadequate choice for a reference gene may obscure genuine changes and/or result in erroneous gene expression data comparisons.

METHODS

In our effort to highlight the importance of selecting the most appropriate reference gene(s), we have screened the literature for gene expression studies published since the turn of the century on thirteen of the most prevalent human cancers worldwide.

CONCLUSIONS

Based on the analysis of the data at hand, we firstly recommend that in each study the suitability of candidate reference gene(s) should carefully be evaluated in order to yield reliable differential gene expression data. Secondly, we recommend that a combination of PPIA and either GAPDH, ACTB, HPRT and TBP, or appropriate combinations of two or three of these genes, should be employed in future studies, to ensure that results from different studies on different human cancers can be harmonized. This approach will ultimately increase the depth of our understanding of gene expression signatures across human cancers.

Distribution of Ki67 proliferative indices among WHO subtypes of non-Hodgkin's lymphoma: association with other clinical parameters

BACKGROUND

Non-hodgkin lymphoma (NHL) is a diverse group of disease encompassing divergent tumor types with contrasting clinical behaviors. We aimed to evaluate the usefulness of Ki67 index in segregating indolent from aggressive NHL and its association with clinical parameters.

MATERIALS AND METHODS

During a study period of 4.5 years, a total of 215 cases of lymphomas were diagnosed among of which 172 cases were NHL. Ki67 immunohistochemical staining was performed by the DAKO envision method. Average proportion of tumor cells stained was calculated to determine the proliferative index.

RESULTS

The mean age at diagnosis was 46.2 years +19.8 (3-81) with a male to female ratio of 1.5:1. Mean Ki67 index for indolent NHL included 23% for small cell, 25% for mantle cell, 28.5% for marginal zone and 34.6% for follicular lymphoma. On the other hand, mean Ki67 index for aggressive lymphomas were 66.4%, 66.9%, 80.3%, 83.3% and 94.4% for diffuse large B cell, T cell (NOS), anaplastic large cell, lymphoblastic and burkitts lymphoma respectively. No significant correlation was found between Ki67 index and other clinical parameters like age and extra nodal involvement.

CONCLUSIONS

Ki67 index is a valuable IHC marker to distinguish indolent from aggressive lymphomas especially in small needle biopsies where exact typing may not be possible.

Type distribution of lymphomas in Lebanon: five-year single institution experience

BACKGROUND

Lymphomas represent the fifth most frequent cancer in Lebanon. However, little is known concerning epidemiologic characteristics and distribution of lymphoid neoplasms according to the 2008 WHO classification.

MATERIALS AND METHODS

We conducted a retrospective study of lymphoma cases diagnosed from 2008 till 2012 at Hotel-Dieu de France University Hospital.

RESULTS

A total of 502 new cases of lymphoma were diagnosed at our institution during a five year period: 119 cases (24%) were Hodgkin lymphomas (HL) and 383 cases (76%) were non-Hodgkin lymphomas (NHL). HLs were equally distributed in both sexes with a mean age at diagnosis of 30 years. Among NHL, 87% (332 cases) were B cell lymphomas, 9% (34 cases) were T cell lymphomas and 4%(17 cases) were classified as precursor lymphoid neoplasms. Among B cell lymphomas, 44% (147 cases) were diffuse large B cell lymphomas (DLBCL), 20% (65 cases) follicular lymphomas and 8% (27 cases) mantle cell lymphomas. DLBCL were equally distributed in both sexes with a mean age of 58 years. Follicular lymphomas were characterized by a male predominance (57%) and a mean age of 60 years. Mantle cell lymphomas showed a pronounced male predominance (85%) with a mean age of 60 years in men and 70 years in women. Some 72% of patients having T cell lymphomas were men, with a mean age of 57 years in men and 45 years in women, while 65% of patients having precursor lymphoid neoplasms were women with a mean age of 22 years in women and 30 years in men.

CONCLUSIONS

The lymphoma subtype distribution in Lebanon is unique when compared to other countries from around the world. In fact, Hodgkin and follicular lymphomas are more frequent than in most Far Eastern, European and American countries, while T-cell lymphomas and DLBCL are less frequent.

Lack of association between using aspirin and development of non-Hodgkins lymphoma: a meta-analysis

BACKGROUND

Non-Hodgkins lymphoma (NHL) is a heterogeneous group of malignancies, originating in the lymphatic organs, whose incidence is increasing in developed as well as developing countries. Epidemiological evidence suggests that aspirin may reduce the incidence and mortality of several cancers. The main objective of this study was to evaluate the potential relationship between using aspirin and development of NHL with a meta-analysis.

MATERIALS AND METHODS

A total of 7 studies were included. Outcome was calculated and reported as odds ratios (ORs). Heterogeneity was assessed with Cochrane Q and I2 statistics. Dissemination bias was evaluated by funnel plot visualization and trim-and-fill analysis.

RESULTS

Our analysis showed OR of developing NHL overall of 1(95% CI: 0.87-1.16, p=0.9), and in females this was 0.81 (95%CI: 0.72-.92, p=0.001) and in males 1.01 (95%CI: 0.82-1.26, p=0.86). The odds ratio (OR) of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) was 0.85 (95%CI: 0.75-0.97, p=0.02), The ORs of follicular lymphoma (FL) and large B-cell lymphoma (DLBCL) in individuals exposed to aspirin were 1.12 (95%CI: 0.86-1.45, p=0.37) and 1.03 (95%CI: 0.9-1.19, p=0.6) respectively.

CONCLUSIONS

In conclusion, individuals taking aspirin do not demonstrate any change in risk of Non-Hodgkins lymphoma.

Clinicopathologic and survival characteristics of childhood and adolescent non Hodgkin's lymphoma in Yazd, Iran

BACKGROUND

Data regarding childhood and adolescent non Hodgkin lymphomas in Iran are limited. The aim of this study was to assess the epidemiological and histomorphological features and survival of affected patients in our center.

MATERIALS AND METHODS

The clinicopathologic features and outcome of 44 children and adolescents with non Hodgkin lymphoma diagnosed during 2004-2012, were investigated retrospectively. The influence of potential prognostic parameters in overall survival was investigated by log-rank test and Cox regression analysis.

RESULTS

The mean age at presentation was 13.8 ± 6.16 years with a male predilection (M: F=3:1). Malignant lymphoma, not otherwise specified, diffuse large cell lymphoma and Burkitt lymphoma were the three most common histological types observed. The tumors were 36.4% intermediate grade, 27.3% high grade and 34.1% belonged to the malignant lymphoma not otherwise specified group. Immunohistochemistry findings were available in 39 cases. Out of these cases 33 (84.6%) had B cell lineage, 4 (10.25%) T cell lineage and 2 (5.12%) of the cases belonged to miscellaneous group. 3 year and 5 year survivals were 48% and 30% respectively and median survival was 36 months (95%CI=21.7-50.3 months). Overall survival in patients with high grade tumors was 19.5 months, in the intermediate group,79 months , and for malignant lymphomas not otherwise specified it was 33.6 months (p value=0.000).

CONCLUSIONS

The survival rate for children and adolescents with non Hodgkin lymphomas at our center during 2004-2012 was at a low level.