Follicular lymphoma (FL) is an indolent disease, but 30%–40% of cases undergo histologic transformation to an aggressive malignancy, typically represented by diffuse large B cell lymphoma (DLBCL). ...The pathogenesis of this process remains largely unknown. Using whole-exome sequencing and copy-number analysis, we show here that the dominant clone of FL and transformed FL (tFL) arise by divergent evolution from a common mutated precursor through the acquisition of distinct genetic events. Mutations in epigenetic modifiers and antiapoptotic genes are introduced early in the common precursor, whereas tFL is specifically associated with alterations deregulating cell-cycle progression and DNA damage responses (CDKN2A/B, MYC, and TP53) as well as aberrant somatic hypermutation. The genomic profile of tFL shares similarities with that of germinal center B cell-type de novo DLBCL but also displays unique combinations of altered genes with diagnostic and therapeutic implications.
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•FL and tFL arise from a common mutated precursor clone by divergent evolution•Epigenetic modifiers and antiapoptotic genes are mutated in the common precursor•Biallelic disruption of CDKN2A/B and deregulation of MYC are specific to tFL•tFL displays a unique genomic profile with only partial similarity to DLBCL
Follicular lymphoma (FL) is an indolent disease but can undergo transformation to a fatal malignancy, typically diffuse large B cell lymphoma (DLBCL). Pasqualucci, Dalla-Favera, and colleagues now find that the dominant clone of FL and transformed FL (tFL) arise by divergent evolution from a common mutated precursor through distinct genetic events, including CDKN2A/B loss, MYC deregulation, and aberrant somatic hypermutation being specifically acquired at transformation. The genomic profile of tFL shares similarities with that of germinal center B cell-type de novo DLBCL but also displays unique combinations of altered genes with diagnostic and therapeutic implications.
Nodal marginal zone lymphoma (NMZL) is a rare, indolent B-cell tumor that is distinguished from splenic marginal zone lymphoma (SMZL) by the different pattern of dissemination. NMZL still lacks ...distinct markers and remains orphan of specific cancer gene lesions. By combining whole-exome sequencing, targeted sequencing of tumor-related genes, whole-transcriptome sequencing, and high-resolution single nucleotide polymorphism array analysis, we aimed at disclosing the pathways that are molecularly deregulated in NMZL and we compare the molecular profile of NMZL with that of SMZL. These analyses identified a distinctive pattern of nonsilent somatic lesions in NMZL. In 35 NMZL patients, 41 genes were found recurrently affected in ≥3 (9%) cases, including highly prevalent molecular lesions of MLL2 (also known as KMT2D; 34%), PTPRD (20%), NOTCH2 (20%), and KLF2 (17%). Mutations of PTPRD, a receptor-type protein tyrosine phosphatase regulating cell growth, were enriched in NMZL across mature B-cell tumors, functionally caused the loss of the phosphatase activity of PTPRD, and were associated with cell-cycle transcriptional program deregulation and increased proliferation index in NMZL. Although NMZL shared with SMZL a common mutation profile, NMZL harbored PTPRD lesions that were otherwise absent in SMZL. Collectively, these findings provide new insights into the genetics of NMZL, identify PTPRD lesions as a novel marker for this lymphoma across mature B-cell tumors, and support the distinction of NMZL as an independent clinicopathologic entity within the current lymphoma classification.
•PTPRD lesions are among the most recurrent alterations in NMZL and appear to be enriched in this lymphoma type across mature B-cell tumors.•NMZL and SMZL genetics overlap with the exceptions of PTPRD lesions, supporting their distinction as independent entities.
The contribution of epigenomic alterations to tumour progression and relapse is not well characterized. Here we characterize an association between disease progression and DNA methylation in diffuse ...large B-cell lymphoma (DLBCL). By profiling genome-wide DNA methylation at single-base pair resolution in thirteen DLBCL diagnosis-relapse sample pairs, we show that DLBCL patients exhibit heterogeneous evolution of tumour methylomes during relapse. We identify differentially methylated regulatory elements and determine a relapse-associated methylation signature converging on key pathways such as transforming growth factor-β (TGF-β) receptor activity. We also observe decreased intra-tumour methylation heterogeneity from diagnosis to relapsed tumour samples. Relapse-free patients display lower intra-tumour methylation heterogeneity at diagnosis compared with relapsed patients in an independent validation cohort. Furthermore, intra-tumour methylation heterogeneity is predictive of time to relapse. Therefore, we propose that epigenomic heterogeneity may support or drive the relapse phenotype and can be used to predict DLBCL relapse.
A comprehensive analysis of the immune cell infiltrate collected from pleural fluid and from biopsy specimens of malignant pleural mesothelioma (MPM) may contribute to understanding the ...immune-evasion mechanisms related to tumor progression, aiding in differential diagnosis and potential prognostic stratification. Until now such approach has not routinely been verified.
We enrolled 275 patients with an initial clinical diagnosis of pleural effusion. Specimens of pleural fluids and pleural biopsy samples used for the pathologic diagnosis and the immune phenotype analyses were blindly investigated by multiparametric flow cytometry. The results were analyzed using the Kruskal-Wallis test. The Kaplan-Meier and log-rank tests were used to correlate immune phenotype data with patients’ outcome.
The cutoffs of intratumor T-regulatory (>1.1%) cells, M2-macrophages (>36%), granulocytic and monocytic myeloid-derived suppressor cells (MDSC; >5.1% and 4.2%, respectively), CD4 molecule–positive (CD4+) programmed death 1–positive (PD-1+) (>5.2%) and CD8+PD-1+ (6.4%) cells, CD4+ lymphocyte activating 3–positive (LAG-3+) (>2.8% ) and CD8+LAG-3+ (>2.8%) cells, CD4+ T cell immunoglobulin and mucin domain 3–positive (TIM-3+) (>2.5%), and CD8+TIM-3+ (>2.6%) cells discriminated MPM from pleuritis with 100% sensitivity and 89% specificity. The presence of intratumor MDSC contributed to the anergy of tumor-infiltrating lymphocytes. The immune phenotype of pleural fluid cells had no prognostic significance. By contrast, the intratumor T-regulatory and MDSC levels significantly correlated with progression-free and overall survival, the PD-1+/LAG-3+/TIM-3+ CD4+ tumor-infiltrating lymphocytes correlated with overall survival.
A clear immune signature of pleural fluids and tissues of MPM patients may contribute to better predict patients’ outcome.
Splenic marginal zone lymphoma (SMZL) is a B cell malignancy of unknown pathogenesis, and thus an orphan of targeted therapies. By integrating whole-exome sequencing and copy-number analysis, we show ...that the SMZL exome carries at least 30 nonsilent gene alterations. Mutations in NOTCH2, a gene required for marginal-zone (MZ) B cell development, represent the most frequent lesion in SMZL, accounting for ∼20% of cases. All NOTCH2 mutations are predicted to cause impaired degradation of the NOTCH2 protein by eliminating the C-terminal PEST domain, which is required for proteasomal recruitment. Among indolent B cell lymphoproliferative disorders, NOTCH2 mutations are restricted to SMZL, thus representing a potential diagnostic marker for this lymphoma type. In addition to NOTCH2, other modulators or members of the NOTCH pathway are recurrently targeted by genetic lesions in SMZL; these include NOTCH1, SPEN, and DTX1. We also noted mutations in other signaling pathways normally involved in MZ B cell development, suggesting that deregulation of MZ B cell development pathways plays a role in the pathogenesis of ∼60% SMZL. These findings have direct implications for the treatment of SMZL patients, given the availability of drugs that can target NOTCH, NF-κB, and other pathways deregulated in this disease.
Strong prognostic markers able to stratify lung adenocarcinoma (ADC) patients are lacking. We evaluated whether a six-immunohistochemical markers panel (TTF1, SP-A, Napsin A, MUC5AC, CDX2 and CK5), ...defining the putative neoplastic “cell of origin,” allows to identify prognostic subgroups among lung ADC. We screened a large cohort of ADC specimens (2003–2013) from Torino Institutional Repository identifying: (i) marker positivity by immunohistochemistry, (ii) main morphological appearance by light microscopy, (iii) presence of “hotspot” mutations of candidate genes by Sequenom technology. To evaluate possible predictors of survival and time to recurrence, uni- and multivariable-adjusted comparisons were performed. We identified 4 different subgroups: “alveolar,” “bronchiolar,” “mixed” and “null type." Alveolar-differentiated ADC were more common in young (P=.065), female (P=.083) patients, frequently harboring EGFR-mutated (P=.003) tumors with acinar pattern (P<.001). Bronchiolar-differentiated ADC were more associated with mucinous and solid pattern (P<.001), higher degree of vascular invasion (P=.01) and KRAS gene mutations (P=.07). Bronchiolar, mixed, and null types were independent negative predictors for overall survival, and the latter two had a shorter time to recurrence. This “Cell of Origin” classifier is more predictable than morphology and genetics and is an independent predictor of survival on a multivariate analysis.
•Lung adenocarcinomas are composed by a multitude of different tumors.•Integration of techniques is helpful to better stratify this type of cancer.•Lung adenocarcinomas have diverse embryogenetic derivations.•Cell of origin markers identify different subgroups of patients.•Phenotype classes are able to better predict overall survival trends.
•Testosterone at high levels can induce apoptosis in prostate cancer cells.•Bipolar androgen therapy may prolong response in prostate cancer.•Many mechanisms, including DNA damage, are involved in ...cells death.•Clinical trials have shown some benefit from bipolar androgen therapy.•Combinations with immunotherapy and PARP inhibitors are under investigation.
Testosterone suppression by androgen deprivation therapy is the cornerstone of prostate cancer treatment. New-generation hormone therapies improved overall survival in castration-resistant prostate cancer. More recent trials showed a further increase in overall survival when enzalutamide or abiraterone are associated with androgen deprivation therapy in hormone-sensitive disease. However, a higher clonal pressure may lead to the upregulation of alternative pathways for cancer progression and to dedifferentiated diseases that would probably respond poorly to subsequent treatments. In this contest, new strategies that could be able to delay or even revert resistance are needed. The bipolar androgen therapy is an under-investigation treatment that consists in periodical oscillation between castration levels and supraphysiological levels of testosterone in order to prevent the adaptation of prostate cancer cells to a low-androgen environment. This review aims to underline the biological rationale of bipolar androgen therapy and gather evidences from the most recent clinical trials.
Histone deacetylases (HDACs) play crucial roles in cancers, but the role and mechanism of HDAC7 in NSCLC have not been fully understood.
A total of 319 patients with non-small cell lung cancer ...(NSCLC) who underwent surgery were enrolled in this study. Immunohistochemistry and Kaplan-Meier survival analysis were performed to investigate the relationship between HDAC7, fibroblast growth factor 18 (FGF18) expression, and clinicopathologic characteristics. Cell functional experiments were implemented both in vivo and in vitro to investigate the effects on NSCLC cell proliferation and metastasis. Recombinant lentivirus-meditated in vivo gene overexpression or knockdown, real-time polymerase chain reaction (PCR), western blotting, and coimmunoprecipitation assays were applied to clarify the underlying molecular mechanism of HDAC7 in promoting NSCLC progression.
The elevated expression of HDAC7 or FGF18 was positively correlated with poor prognosis, tumor-node-metastasis (TNM) stage, and tumor differentiation of NSCLC patients. NSCLC patients with co-expressed HDAC7 and FGF18 suffered the worst prognosis. HDAC7 overexpression promoted NSCLC proliferation and metastasis by upregulating FGF18. Conversely, overexpression of FGF18 reversed the attenuated ability in tumor growth and metastasis mediated by downregulating HDAC7. In terms of mechanism, our results suggested that the interaction of HDAC7 with β-catenin caused decreased β-catenin acetylation level at Lys49 and decreased phosphorylation level at Ser45. As a consequence, the HDAC7-mediated posttranslational modification of β-catenin facilitated nuclear transfer and activated FGF18 expression via binding to TCF4. Furthermore, deubiquitinase USP10 interacted with and stabilized HDAC7. The suppression of USP10 significantly accelerated the degradation of HDAC7 and weakened NSCLC growth and migration.
Our findings reveal that HDAC7 promotes NSCLC progression through being stabilized by USP10 and activating the β-catenin-FGF18 pathway. Targeting this novel pathway may be a promising strategy for further developments in NSCLC therapy.
•BRAF-V600E is a mandatory mutation to be obtained at the diagnosis for advanced non-squamous NSCLC.•The combination of dabrafenib + trametinib represents the gold standard treatment for BRAF-V600E ...patients.•The non-V600 mutations are half of the BRAF mutations in NSCLC and are sub-classified in class 2 and 3.•Classical BRAF + MEK inhibition demonstrated efficacy in sporadic cases of non-V600 patients.•Regimens based on MEK-inhibitors + next-generation RAF-inhibitors seems active in non-V600 patients.
The advent of high-throughput sequencing has allowed to profoundly interrogate the molecular landscape of non-small cell lung cancer (NSCLC) in the last years. These findings constitute the opportunity to better stratify these patients in order to address specific treatments to well-defined oncogene-restricted subgroups. Among them, BRAF-mutated lung cancers represent around 4% of NSCLC, thus identifying a clinically relevant population that should be aptly managed. Pivotal phase II trials have demonstrated the efficacy of combinatorial treatment - dabrafenib plus trametinib, targeting both BRAF and MEK - for patients harboring V600E mutations, making this specific BRAF alteration a mandatory requirement in the genetic portrait of advanced non-squamous lung cancer patients. However, around half of BRAF+ NSCLC patients remain orphan of targeted approaches. Here we review the available evidence, mainly from a clinical perspective, of therapeutic strategies for both V600E and non-V600 patients, in terms of small molecule, immune checkpoint inhibitors and forthcoming integrated strategies. Looking at on-going clinical trials, a special attention is dedicated to emergent molecules and combinatorial strategies that not only will improve outcomes of classical V600E, but also will make concrete the chance of tailored treatments for the majority of BRAF-mutated patients.
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