Non-Hodgkin lymphomas (NHL) represent the most common hematologic malignancies. Patient-derived xenografts (PDXs) are used for various aspects of translational research including preclinical in vivo validation of experimental treatment approaches. While it was repeatedly demonstrated that PDXs keep majority of somatic mutations with the primary lymphoma samples, from which they were derived, the composition of PDX tumor microenvironment (TME) has not been extensively studied. We carried out a comparative genetic and histopathological study of 15 PDX models derived from patients with various types of NHL including diffuse large B-cell lymphoma (DLBCL; n = 7), Burkitt lymphoma (BL; n = 1), mantle cell lymphoma (MCL; n = 2), and peripheral T-cell lymphomas (PTCL; n = 5). Whole exome sequencing (WES) of the PDXs and primary lymphoma cells was implemented in 13 out of 15 cases with available DNA samples. Standard immunohistochemistry (IHC) was used to analyze the composition of PDX TME. WES data confirmed that PDXs maintained the genetic heterogeneity with the original primary lymphoma cells. In contrast, IHC analysis revealed the following recurrently observed alterations in the composition of PDX tumors: more blastoid lymphoma cell morphology, increased proliferation rate, lack of non-malignant cellular components including T cells and (human or murine) macrophages, and significantly lower intratumoral microvessel density and microvessel area composed of murine vessels. In addition, PDX tumors derived from T-NHL displayed additional differences compared to the primary lymphoma samples including markedly lower desmoplasia (i.e., the extent of both reticular and collagen fibrosis), loss of expression of cytotoxic granules (i.e., perforin, TIA, granzyme B), or loss of expression of T-cell specific antigens (i.e., CD3, CD4, CD8). Our data suggest that despite keeping the same genetic profiles, PDX models of aggressive NHL do not recapitulate the microenvironmental heterogeneity of the original lymphomas. These findings have implications on the relevance of PDX models in the context of preclinical research.

• MeSH
• Antineoplastic Agents * MeSH
• Lymphoma, Large B-Cell, Diffuse * MeSH
• Adult MeSH
• Heterografts MeSH
• Humans MeSH
• Disease Models, Animal MeSH
• Mice MeSH
• Tumor Microenvironment MeSH
• Animals MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Non-Hodgkin lymphomas (NHL) represent the most common hematologic malignancies. Patient-derived xenografts (PDXs) are used for various aspects of translational research including preclinical in vivo validation of experimental treatment approaches. While it was repeatedly demonstrated that PDXs keep majority of somatic mutations with the primary lymphoma samples, from which they were derived, the composition of PDX tumor microenvironment (TME) has not been extensively studied. We carried out a comparative genetic and histopathological study of 15 PDX models derived from patients with various types of NHL including diffuse large B-cell lymphoma (DLBCL; n = 7), Burkitt lymphoma (BL; n = 1), mantle cell lymphoma (MCL; n = 2), and peripheral T-cell lymphomas (PTCL; n = 5). Whole exome sequencing (WES) of the PDXs and primary lymphoma cells was implemented in 13 out of 15 cases with available DNA samples. Standard immunohistochemistry (IHC) was used to analyze the composition of PDX TME. WES data confirmed that PDXs maintained the genetic heterogeneity with the original primary lymphoma cells. In contrast, IHC analysis revealed the following recurrently observed alterations in the composition of PDX tumors: more blastoid lymphoma cell morphology, increased proliferation rate, lack of non-malignant cellular components including T cells and (human or murine) macrophages, and significantly lower intratumoral microvessel density and microvessel area composed of murine vessels. In addition, PDX tumors derived from T-NHL displayed additional differences compared to the primary lymphoma samples including markedly lower desmoplasia (i.e., the extent of both reticular and collagen fibrosis), loss of expression of cytotoxic granules (i.e., perforin, TIA, granzyme B), or loss of expression of T-cell specific antigens (i.e., CD3, CD4, CD8). Our data suggest that despite keeping the same genetic profiles, PDX models of aggressive NHL do not recapitulate the microenvironmental heterogeneity of the original lymphomas. These findings have implications on the relevance of PDX models in the context of preclinical research.

• MeSH
• Antineoplastic Agents * MeSH
• Lymphoma, Large B-Cell, Diffuse * genetics   MeSH
• Adult MeSH
• Immunohistochemistry MeSH
• Humans MeSH
• Mice MeSH
• Tumor Microenvironment genetics   MeSH
• Animals MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

• MeSH
• Cyclophosphamide administration & dosage   MeSH
• Adult MeSH
• Doxorubicin administration & dosage   MeSH
• Middle Aged MeSH
• Humans MeSH
• Lymphoma, Mantle-Cell * drug therapy   genetics   mortality   MeSH
• Survival Rate MeSH
• Mutation * MeSH
• Tumor Suppressor Protein p53 genetics   MeSH
• Prednisone administration & dosage   MeSH
• Disease-Free Survival MeSH
• Antineoplastic Combined Chemotherapy Protocols administration & dosage   MeSH
• Retrospective Studies MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Vincristine administration & dosage   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Letter MeSH
• Research Support, Non-U.S. Gov't MeSH

Mantle cell lymphoma (MCL) is a subtype of B-cell lymphoma with a large number of recurrent cytogenetic/molecular aberrations. Approximately 5-10% of patients do not respond to frontline immunochemotherapy. Despite many useful prognostic indexes, a reliable marker of chemoresistance is not available. We evaluated the prognostic impact of seven recurrent gene aberrations including tumor suppressor protein P53 (TP53) and cyclin dependent kinase inhibitor 2A (CDKN2A) in the cohort of 126 newly diagnosed consecutive MCL patients with bone marrow involvement ≥5% using fluorescent in-situ hybridization (FISH) and next-generation sequencing (NGS). In contrast to TP53, no pathologic mutations of CDKN2A were detected by NGS. CDKN2A deletions were found exclusively in the context of other gene aberrations suggesting it represents a later event (after translocation t(11;14) and aberrations of TP53, or ataxia telangiectasia mutated (ATM)). Concurrent deletion of CDKN2A and aberration of TP53 (deletion and/or mutation) represented the most significant predictor of short EFS (median 3 months) and OS (median 10 months). Concurrent aberration of TP53 and CDKN2A is a new, simple, and relevant index of chemoresistance in MCL. Patients with concurrent aberration of TP53 and CDKN2A should be offered innovative anti-lymphoma therapy and upfront consolidation with allogeneic stem cell transplantation.

• Publication type
• Journal Article MeSH

• MeSH
• Survival Analysis MeSH
• Transplantation, Autologous MeSH
• Progression-Free Survival MeSH
• Adult MeSH
• Remission Induction methods   MeSH
• Middle Aged MeSH
• Humans MeSH
• Lymphoma, Mantle-Cell mortality   therapy   MeSH
• Antineoplastic Combined Chemotherapy Protocols therapeutic use   MeSH
• Rituximab therapeutic use   MeSH
• Aged MeSH
• Hematopoietic Stem Cell Transplantation MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Letter MeSH
• Clinical Trial MeSH
• Research Support, Non-U.S. Gov't MeSH

Úvod: Invazivní mykotické infekce představují život ohrožující infekční komplikace u hematologických pacientů a jejich časná diagnostika může přispět ke zlepšení přežívání těchto nemocných. Jejich zastoupení se v posledních letech mění zejména vlivem selekčního tlaku antimykotik. Materiál a metodika: Cílem naší práce bylo retrospektivní zhodnocení změn v epidemiologii invazivních aspergilóz, invazivních kandidóz a vzácných mykóz u hematologických nemocných v českých a slovenských hematoonkologických centrech v letech 2005–2017. Sledované období bylo rozděleno na 1. období (2005–2012) a 2. období (2013–2017). K analýze byla použita data zadaná do databáze FIND (Fungal INfection Database) na základě diagnostických EORTC/ MSG kritérií z roku 2008. Spotřeba vybraných antimykotik byla vyjádřena v relativní roční spotřebě na 1 000 lůžkodní. Výsledky: Celkem bylo zdokumentováno 349 invazivních aspergilóz, 168 invazivních kandidóz a 102 vzácných mykóz (z toho 65,7 % invazivních zygomykóz). Výskyt invazivní aspergilózy vzrůstal v 1. období, přičemž od roku 2013 nastal naopak klesající trend (průměrný počet případů na centrum v letech 2005–2012–2017: 1,1–3,6–0,7). Snížilo se zastoupení invazivních aspergilóz u vysoce rizikových pacientů (2005 – 72,7 %; 2010 – 40,7 %; 2017 – 18,2 %). Celková spotřeba posakonazolu rostla od roku 2005 (rDDD v roce 2005–2010–2015: 0–831–1043). Celkový počet invazivních kandidóz a vzácných mykóz zůstal v letech neměnný. Zastoupení druhů Candida albicans vs. non-albicans se také v 1. a 2. období nelišilo (26,1 % vs. 29,1 %; p = 0,732). U průlomových infekcí na profylaxi posakonazolem nebo vorikonazolem se signifikantně častěji vyskytovaly vzácné patogeny ve srovnání s infekcemi vzniklými u pacientů bez této profylaxe (35,3 % vs. 14,4 %; p = 0,000). Závěr: Na základě analýzy byl potvrzen klesající výskyt invazivních aspergilóz dominantně v souvislosti se zavedením rutinní antimykotické profylaxe posakonazolem u vysoce rizikových pacientů. Zastoupení zygomykózy u těchto nemocných také kleslo. U pacientů na profylaxi posakonazolem nebo vorikonazolem došlo ke změně spektra infekcí ve prospěch vzácných patogenů.

Background: Invasive fungal diseases are life-threatening infectious complications affecting haematological patients and their early diagnosis can contribute to improved survival of affected patients. In the last years, the patterns of invasive fungal infections have changed mainly due to the selection pressure of antifungals. Material and Methods: The aim of our analysis to evaluate retrospectively changes in the epidemiology of invasive aspergillosis, invasive candidiasis and rare mycoses in haematological patients at Czech and Slovak haematological centres from 2005–2017. The observed period was divided into: 2005–2012 (1st period) and 2013–2017 (2nd period). Data entered into FIND – Fungal INfection Database (according to the EORTC/MSG criteria from 2008) was used for the analysis. The total consumption of posaconazole and micafungin was expressed in relative annual consumption per 1000 bed-days. Results: A total of 349 invasive aspergillosis, 168 invasive candidiasis and 102 rare mycoses (65.7% invasive zygomycosis) were documented. The incidence of aspergillosis increased from 2005 to 2012, with a declining trend since 2013 (the average number of cases per centre in 2005–2012–2017 was: 1.1–3.6–0.7). The incidence of aspergillosis in high risk patients decreased (2005 – 72.7%, 2013 – 42.4%, 2017 – 18.2%). Total consumption of posaconazole has been on the increase since 2005 (rDDD in 2005-2010-2015: 0-831-1043). The total number of invasive candidiasis and rare mycoses remained unchanged over the years. The Candida albicans vs. non-albicans ratio remained unchanged in the 1st and 2nd periods (26.1% vs. 29.1%, p=0.732). There was a significant increase in rare mycoses in breakthrough infections on posaconazole or voriconazole prophylaxis compared to non-breakthrough infections (35.3% vs. 14.4%). Conclusion: Based on our analysis, we have confirmed a decrease in the incidence of invasive aspergillosis from 2013 after the introduction of routine antifungal prophylaxis with posaconazole in high-risk patients. The ratio of high-risk patients with invasive zygomycosis has also decreased. Patients on posaconazole or voriconazole prophylaxis have changed the spectrum of infections in favour of rare pathogens.

• Keywords
• hematologický pacient,
• MeSH
• Precursor Cell Lymphoblastic Leukemia-Lymphoma complications   MeSH
• Adult MeSH
• Hematologic Neoplasms * complications   MeSH
• Invasive Fungal Infections * epidemiology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Retrospective Studies MeSH
• Aged MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Aged MeSH

PURPOSE: Mantle cell lymphoma (MCL) is an aggressive subtype of B-cell non-Hodgkin lymphomas characterized by (over)expression of BCL2. A BCL2-targeting drug, venetoclax, has promising anticancer activity in MCL. We analyzed molecular mechanisms of venetoclax resistance in MCL cells and tested strategies to overcome it. EXPERIMENTAL DESIGN: We confirmed key roles of proapoptotic proteins BIM and NOXA in mediating venetoclax-induced cell death in MCL. Both BIM and NOXA are, however, differentially expressed in cell lines compared with primary cells. First, NOXA protein is significantly overexpressed in most MCL cell lines. Second, deletions of BIM gene harbored by three commonly used MCL cell lines (JEKO-1, MINO, and Z138) were not found by array comparative genomic hybridization using a validation set of 24 primary MCL samples. RESULTS: We demonstrated that MCL1 and NOXA play important roles in mediating resistance to venetoclax. Consequently, we tested an experimental treatment strategy based on cotargeting BCL2 with venetoclax and MCL1 with a highly specific small-molecule MCL1 inhibitor S63845. The combination of venetoclax and S63845 demonstrated synthetic lethality in vivo on a panel of five patient-derived xenografts established from patients with relapsed MCL with adverse cytogenetics. CONCLUSIONS: Our data strongly support investigation of venetoclax in combination with S63845 as an innovative treatment strategy for chemoresistant MCL patients with adverse cytogenetics in the clinical grounds.

• MeSH
• Antineoplastic Agents pharmacology   MeSH
• Bridged Bicyclo Compounds, Heterocyclic pharmacology   MeSH
• Drug Resistance, Neoplasm MeSH
• Humans MeSH
• Neoplasm Recurrence, Local drug therapy   metabolism   pathology   MeSH
• Lymphoma, Mantle-Cell drug therapy   metabolism   pathology   MeSH
• Mice, Inbred NOD MeSH
• Mice MeSH
• Cell Line, Tumor MeSH
• Myeloid Cell Leukemia Sequence 1 Protein antagonists & inhibitors   metabolism   MeSH
• Proto-Oncogene Proteins c-bcl-2 antagonists & inhibitors   metabolism   MeSH
• Pyrimidines pharmacology   MeSH
• Sulfonamides pharmacology   MeSH
• Drug Synergism * MeSH
• Thiophenes pharmacology   MeSH
• Xenograft Model Antitumor Assays MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Mice MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

• Publication type
• Meeting Abstract MeSH

Implementation of cytarabine into induction therapy became standard of care for younger patients with mantle cell lymphoma (MCL). On the basis of its beneficial impact, many centers incorporated cytarabine at lower doses also into first-line treatments of elderly patients. We conducted a multicenter observational study that prospectively analyzed safety and efficacy of alternating 3 + 3 cycles of R-CHOP and R-cytarabine for newly diagnosed transplant-ineligible MCL patients. A total of 73 patients were enrolled with median age 70 years. Most patients had intermediate (39.7%) and high-risk (50.7%) disease according to MCL international prognostic index. Rituximab maintenance was initiated in 58 patients. Overall response rate reached 89% by positron emission tomography-computed tomography, including 75.3% complete remissions. Two patients (2.7%) did not complete the induction therapy because of toxicity. Three patients (4.1%) were considered nonresponders, which led to therapy change before completion of induction. Estimated progression-free survival and overall survival were 51.3% and 68.6% at 4 years, respectively. Mantle cell lymphoma international prognostic index, bulky disease (≥ 5 cm), and achievement of positron emission tomography-negativity independently correlated with progression-free survival. Grade 3 to 4 hematologic and nonhematologic toxicity was documented in 48% and 20.5% patients, respectively. Alternation of R-CHOP and R-cytarabine represents feasible and very effective regimen for elderly/comorbid MCL patients. This study was registered at GovTrial (clinicaltrials.gov) NCT03054883.

• MeSH
• Cyclophosphamide pharmacology   therapeutic use   MeSH
• Cytarabine pharmacology   therapeutic use   MeSH
• Doxorubicin pharmacology   therapeutic use   MeSH
• Middle Aged MeSH
• Humans MeSH
• Lymphoma, Mantle-Cell drug therapy   pathology   MeSH
• Antibodies, Monoclonal, Murine-Derived pharmacology   therapeutic use   MeSH
• Prednisone pharmacology   therapeutic use   MeSH
• Antineoplastic Combined Chemotherapy Protocols pharmacology   therapeutic use   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Vincristine pharmacology   therapeutic use   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Rituximab maintenance (RM) prolongs survival of elderly patients with mantle cell lymphoma (MCL). Persistent minimal residual disease (MRD) after induction repeatedly correlated with shorter progression-free survival (PFS). However, none of the published studies analyzed patients treated with RM. The main purpose was to analyze prognostic significance of MRD in the elderly patients with newly diagnosed MCL treated according to the recently published observational trial protocol (alternation of R-CHOP and R-cytarabine, 3 + 3 cycles, GovTrial number NCT03054883) at the centers that implemented RM. Minimal residual disease was evaluated by a EuroMRD standardized real-time PCR approach after 3 and 6 cycles of the induction therapy. Prognostic significance of MRD was analyzed in a subcohort of patients treated at the centers that implemented RM as a standard approach. Bone marrow proved to be a significantly more sensitive source for MRD detection than peripheral blood. In either compartment MRD (positive versus negative) after 3 or 6 cycles of the induction therapy did not correlate with PFS. The observed loss of prognostic significance of MRD after the R-CHOP-based induction appears to be a consequence of RM immune control over the residual lymphoma.

• MeSH
• Cyclophosphamide administration & dosage   MeSH
• Doxorubicin administration & dosage   MeSH
• Middle Aged MeSH
• Humans MeSH
• Lymphoma, Mantle-Cell * blood   drug therapy   mortality   MeSH
• Survival Rate MeSH
• Antibodies, Monoclonal, Murine-Derived administration & dosage   MeSH
• Follow-Up Studies MeSH
• Prednisone administration & dosage   MeSH
• Disease-Free Survival MeSH
• Antineoplastic Combined Chemotherapy Protocols administration & dosage   MeSH
• Neoplasm, Residual MeSH
• Rituximab administration & dosage   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Maintenance Chemotherapy * MeSH
• Vincristine administration & dosage   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Clinical Trial MeSH
• Multicenter Study MeSH
• Observational Study MeSH