Translationally controlled tumor protein in prostatic adenocarcinoma: correlation with tumor grading and treatment-related changes

12Prostate cancer is the second leading cause of cancer-related death. The androgen deprivation therapy is the standard treatment for advanced stages. Unfortunately, virtually all tumors become resistant to androgen withdrawal. The progression to castration-resistance is not fully understood, although a recent paper has suggested translationally controlled tumor protein to be implicated in the process. The present study was designed to investigate the role of this protein in prostate cancer, focusing on the correlation between its expression level with tumor differentiation and response to treatment. We retrieved 292 prostatic cancer specimens; of these 153 had been treated only by radical prostatectomy and 139 had undergone radical prostatectomy after neoadjuvant treatment with combined androgen blockade therapy. Non-neoplastic controls were represented by 102 prostatic peripheral zone specimens. In untreated patients, the expression of the protein, evaluated by RT-qPCR and immunohistochemistry, was significantly higher in tumor specimens than in non-neoplastic control, increasing as Gleason pattern and score progressed. In treated prostates, the staining was correlated with the response to treatment. An association between protein expression and the main clinicopathological factors involved in prostate cancer aggressiveness was identified. These findings suggest that the protein may be a promising prognostic factor and a target for therapy.openopenRocca, Bruno Jim; Ginori, Alessandro; Barone, Aurora; Calandra, Calogera; Crivelli, Filippo; De Falco, Giulia; Gazaneo, Sara; Tripodi, Sergio; Cevenini, Gabriele; Del Vecchio, Maria Teresa; Ambrosio, Maria Raffaella; Tosi, PieroRocca, BRUNO JIM; Ginori, Alessandro; Barone, Aurora; Calandra, Calogera; Crivelli, Filippo; DE FALCO, Giulia; Gazaneo, Sara; Tripodi, Sergio; Cevenini, Gabriele; DEL VECCHIO, MARIA TERESA; Ambrosio, MARIA RAFFAELLA; Tosi, Pier

MicroRNAs sequencing unveils distinct molecular subgroups of plasmablastic lymphoma

Plasmablastic lymphoma (PBL) is an aggressive lymphoma, often arising in the context of immunodeficiency and associated with Epstein-Barr virus (EBV) infection. The most frequently detected genetic alteration is the deregulation of MYC gene through the translocation - t(8;14)(q24;q32). The diagnosis of PBL is often challenging because it has an overlap in morphology, immunophenotype, cytogenetics and virus association with other lymphomas and plasma cell neoplasms; further, its molecular basis remains elusive. In the present study we aimed to better define the possible contribution of EBV infection as well as miRNA deregulation in PBL pathogenesis. We studied 23 cases of PBL, 19 Burkitt lymphomas (BL), and 17 extra-medullary plasmacytoma (EMPC). We used qPCR and immunohistochemistry to assess EBV latency patterns, while micro-RNA (miRNA) profiling was performed by next generation sequencing (Illumina) and validated by qPCR. Our analysis revealed a non-canonical EBV latency program with the partial expression of some proteins characterizing latency II and the activation of an abortive lytic cycle. Moreover, we identified miRNA signatures discriminating PBL from BL and EMPC. Interestingly, based on the miRNA profile, PBL appeared constituted by two discrete subgroups more similar to either BL or EMPC, respectively. This pattern was confirmed in an independent set of cases studied by qPCR and corresponded to different clinico-pathological features in the two groups, including HIV infection, MYC rearrangement and disease localization. In conclusion, we uncovered for the first time 1) an atypical EBV latency program in PBL; 2) a miRNA signature distinguishing PBL from the closest malignant counterparts; 3) the molecular basis of PBL heterogeneity

HIV-1 Tat induces DNMT over-expression through microRNA dysregulation in HIV-related non Hodgkin lymphomas

Background: A close association between HIV infection and the development of cancer exists. Although the advent of highly active antiretroviral therapy has changed the epidemiology of AIDS-associated malignancies, a better understanding on how HIV can induce malignant transformation will help the development of novel therapeutic agents. Methods: HIV has been reported to induce the expression of DNMT1 in vitro, but still no information is available about the mechanisms regulating DNMT expression in HIV-related B-cell lymphomas. In this paper, we investigated the expression of DNMT family members (DNMT1, DNMT3a/b) in primary cases of aggressive B-cell lymphomas of HIV-positive subjects. Results: Our results confirmed the activation of DNMT1 by HIV in vivo, and reported for the first time a marked up-regulation of DNMT3a and DNMT3b in HIV-positive aggressive B-cell lymphomas. DNMT up-regulation in HIV-positive tumors correlated with down-regulation of specific microRNAs, as the miR29 family, the miR148-152 cluster, known to regulate their expression. Literature reports the activation of DNMTs by the human polyomavirus BKV large T-antigen and adenovirus E1a, through the pRb/E2F pathway. We have previously demonstrated that the HIV Tat protein is able to bind to the pocket proteins and to inactivate their oncosuppressive properties, resulting in uncontrolled cell proliferation. Therefore, we focused on the role of Tat, due to its capability to be released from infected cells and to dysregulate uninfected ones, using an in vitro model in which Tat was ectopically expressed in B-cells. Conclusions: Our findings demonstrated that the ectopic expression of Tat was per se sufficient to determine DNMT up-regulation, based on microRNA down-regulation, and that this results in aberrant hypermethylation of target genes and microRNAs. These results point at a direct role for Tat in participating in uninfected B-cell lymphomagenesis, through dysregulation of the epigenetical control of gene expression

Burkitt lymphoma beyond MYC translocation: N-MYC and DNA methyltransferases dysregulation

BACKGROUND: The oncogenic transcription factor MYC is pathologically activated in many human malignancies. A paradigm for MYC dysregulation is offered by Burkitt lymphoma, where chromosomal translocations leading to Immunoglobulin gene-MYC fusion are the crucial initiating oncogenic events. However, Burkitt lymphoma cases with no detectable MYC rearrangement but maintaining MYC expression have been identified and alternative mechanisms can be involved in MYC dysregulation in these cases. METHODS: We studied the microRNA profile of MYC translocation-positive and MYC translocation-negative Burkitt lymphoma cases in order to uncover possible differences at the molecular level. Data was validated at the mRNA and protein level by quantitative Real-Time polymerase chain reaction and immunohistochemistry, respectively. RESULTS: We identified four microRNAs differentially expressed between the two groups. The impact of these microRNAs on the expression of selected genes was then investigated. Interestingly, in MYC translocation-negative cases we found over-expression of DNA-methyl transferase family members, consistent to hypo-expression of the hsa-miR-29 family. This finding suggests an alternative way for the activation of lymphomagenesis in these cases, based on global changes in methylation landscape, aberrant DNA hypermethylation, lack of epigenetic control on transcription of targeted genes, and increase of genomic instability. In addition, we observed an over-expression of another MYC family gene member, MYCN that may therefore represent a cooperating mechanism of MYC in driving the malignant transformation in those cases lacking an identifiable MYC translocation but expressing the gene at the mRNA and protein levels. CONCLUSIONS: Collectively, our results showed that MYC translocation-positive and MYC translocation-negative Burkitt lymphoma cases are slightly different in terms of microRNA and gene expression. MYC translocation-negative Burkitt lymphoma, similarly to other aggressive B-cell non Hodgkin’s lymphomas, may represent a model to understand the intricate molecular pathway responsible for MYC dysregulation in cancer. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12885-015-1661-7) contains supplementary material, which is available to authorized users

Additional file 1: Table S1. of Burkitt lymphoma beyond MYC translocation: N-MYC and DNA methyltransferases dysregulation

List of inter and intra chromosomal gene fusion detected by fusion-detection pipeline. (XLS 89 kb

Additional file 3: Table S3. of Burkitt lymphoma beyond MYC translocation: N-MYC and DNA methyltransferases dysregulation

Gene set enrichment analysis for gene ontology categories of 64 genes predicted as targets of microRNAs differentially expressed in MYC translocation-positive and -negative BLs. (DOC 67 kb

Distinct Viral and Mutational Spectrum of Endemic Burkitt Lymphoma

Endemic Burkitt lymphoma (eBL) is primarily found in children in equatorial regions and represents the first historical example of a virus-associated human malignancy. Although Epstein-Barr virus (EBV) infection and MYC translocations are hallmarks of the disease, it is unclear whether other factors may contribute to its development. We performed RNA-Seq on 20 eBL cases from Uganda and showed that the mutational and viral landscape of eBL is more complex than previously reported. First, we found the presence of other herpesviridae family members in 8 cases (40%), in particular human herpesvirus 5 and human herpesvirus 8 and confirmed their presence by immunohistochemistry in the adjacent non-neoplastic tissue. Second, we identified a distinct latency program in EBV involving lytic genes in association with TCF3 activity. Third, by comparing the eBL mutational landscape with published data on sporadic Burkitt lymphoma (sBL), we detected lower frequencies of mutations in MYC, ID3, TCF3 and TP53, and a higher frequency of mutation in ARID1A in eBL samples. Recurrent mutations in two genes not previously associated with eBL were identified in 20% of tumors: RHOA and cyclin F (CCNF). We also observed that polyviral samples showed lower numbers of somatic mutations in common altered genes in comparison to sBL specimens, suggesting dual mechanisms of transformation, mutation versus virus driven in sBL and eBL respectively

(A) The presence of mutations in genes previously described in BL is reported, including <i>MYC</i> (50%), <i>DDX3X</i> (35%), <i>ID3</i> (30%), <i>ARID1A</i> (25%), <i>RHOA</i> (20%), <i>TCF3</i> and <i>TP53</i> (15%), and <i>CCND3</i> 1/20 (5%). In addition, a new mutation is shown, involving <i>CCNF</i> and detected in 20% of the cases. (B) Bar plot showing the frequency comparison of virus presence and driver mutations between endemic and sporadic BL. For each comparison we report the p-value associated with rejecting the null hypothesis of equal eBL and sBL prevalences. (C) Distribution of mutations in 5 driver genes. Red points indicate endemic BL, while blue points the sporadic ones.

<p>(A) The presence of mutations in genes previously described in BL is reported, including <i>MYC</i> (50%), <i>DDX3X</i> (35%), <i>ID3</i> (30%), <i>ARID1A</i> (25%), <i>RHOA</i> (20%), <i>TCF3</i> and <i>TP53</i> (15%), and <i>CCND3</i> 1/20 (5%). In addition, a new mutation is shown, involving <i>CCNF</i> and detected in 20% of the cases. (B) Bar plot showing the frequency comparison of virus presence and driver mutations between endemic and sporadic BL. For each comparison we report the p-value associated with rejecting the null hypothesis of equal eBL and sBL prevalences. (C) Distribution of mutations in 5 driver genes. Red points indicate endemic BL, while blue points the sporadic ones.</p

(A) Unsupervised hierarchical clustering of expressed EBV genes demonstrates a diversity of non-canonical latency-associated gene expression programs with a subset of viral episome initiating lytic reactivation as indicated by expression of genes corresponding to the lytic program. (B) LMP-2A is expressed by 40 to 50% of neoplastic cells. LMP-2A stain, O.M.: 40x; (C) LMP-2A expression is identified in a proportion of neoplastic cells ranging from 20 to 30%. LMP-2A stain, O.M.: 40x; (D) BZLF1/ZEBRA positivity is expressed by 5 to 10% of neoplastic cells. BZLF1/ZEBRA stain, O.M.: 40x; (E) BZLF1/ZEBRA expression is detected in few neoplastic cells. BZLF1/ZEBRA stain, O.M.: 40x; (F) BMRF-1/Ea-D expression is observed in 50% of neoplastic cells. BMRF-1/Ea-D stain, O.M.: 40x; (G) BMRF-1/Ea-D protein expression in 5% to 10% of neoplastic cells is shown. BMRF-1/Ea-D stain, O.M.: 40x; (H) BHRF-1/Ea-R staining is found in 60% of neoplastic cells. BHRF-1/Ea-R stain, O.M.: 40x; (I) BHRF-1/Ea-R is

<p>(A) Unsupervised hierarchical clustering of expressed EBV genes demonstrates a diversity of non-canonical latency-associated gene expression programs with a subset of viral episome initiating lytic reactivation as indicated by expression of genes corresponding to the lytic program. (B) LMP-2A is expressed by 40 to 50% of neoplastic cells. LMP-2A stain, O.M.: 40x; (C) LMP-2A expression is identified in a proportion of neoplastic cells ranging from 20 to 30%. LMP-2A stain, O.M.: 40x; (D) BZLF1/ZEBRA positivity is expressed by 5 to 10% of neoplastic cells. BZLF1/ZEBRA stain, O.M.: 40x; (E) BZLF1/ZEBRA expression is detected in few neoplastic cells. BZLF1/ZEBRA stain, O.M.: 40x; (F) BMRF-1/Ea-D expression is observed in 50% of neoplastic cells. BMRF-1/Ea-D stain, O.M.: 40x; (G) BMRF-1/Ea-D protein expression in 5% to 10% of neoplastic cells is shown. BMRF-1/Ea-D stain, O.M.: 40x; (H) BHRF-1/Ea-R staining is found in 60% of neoplastic cells. BHRF-1/Ea-R stain, O.M.: 40x; (I) BHRF-1/Ea-R is expressed in 10% of neoplastic cells. BHRF-1/Ea-R stain, O.M.: 40x.</p