AIM: The purpose of this project was to compare the characteristics of two experimental murine models of primary intraocular lymphoma (PIOL) and determine which experimental model is most suitable for further investigational research to elucidate the pathophysiology of PIOL and to find new therapeutical strategies. METHODS: In both experimental models PIOL was induced in immunocompetent mice with intravitreal injection of syngeneic B-cell lymphoma cell lines. Murine strain C3H/HeN and cell line 38C13 were used in the first model and BALB/CaNn mice and cell line A20 in the second model. During the experiments, thorough clinical evaluation (using photo documentation, ultrasonography, and MRI) and histological evaluation were performed. RESULTS: In both models, the percentage of PIOL development was high, reaching nearly 80%. Disease progression was faster in C3H/HeN with exophthalmos occurring on average on day 10. Vitreous involvement was a predominant sign in the clinical presentation of this group. In BALB/CaNn mice exophthalmos occurred on average on day 22. The predominant clinical sign in the BALB/CaNn group was tumorous infiltration of the retina, optic disc, and tumorous retinal detachment. CONCLUSION: Slower progression of the disease in BALB/CaNn mice, greater possibility to examine the retina due to mild vitreous involvement, and later occurrence of exophthalmos makes this strain more suitable for further investigational research.
- MeSH
- B-buněčný lymfom patologie MeSH
- modely nemocí na zvířatech * MeSH
- myši inbrední BALB C * MeSH
- myši inbrední C3H MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nitrooční lymfom * patologie MeSH
- progrese nemoci MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
BACKGROUND: Mantle cell lymphoma (MCL) is a chronically relapsing malignancy with deregulated cell cycle progression. We analyzed efficacy, mode of action, and predictive markers of susceptibility to palbociclib, an approved CDK 4/6 inhibitor, and its combination with venetoclax, a BCL2 inhibitor. METHODS: A panel of nine MCL cell lines were used for in vitro experiments. Four patient derived xenografts (PDX) obtained from patients with chemotherapy and ibrutinib-refractory MCL were used for in vivo proof-of-concept studies. Changes of the mitochondrial membrane potential, energy-metabolic pathways, AKT activity, and pro-apoptotic priming of MCL cells were evaluated by JC-1 staining, Seahorse XF analyser, genetically encoded fluorescent AKT reporter, and BH3 profiling, respectively. MCL clones with gene knockout or transgenic (over)expression of CDKN2A, MYC, CDK4, and RB1 were used to estimate impact of these aberrations on sensitivity to palbociclib, and venetoclax. RESULTS: Co-targeting MCL cells with palbociclib and venetoclax induced cytotoxic synergy in vitro and in vivo. Molecular mechanisms responsible for the observed synthetic lethality comprised palbociclib-mediated downregulation of anti-apoptotic MCL1, increased levels of proapoptotic BIM bound on both BCL2, and BCL-XL and increased pro-apoptotic priming of MCL cells mediated by BCL2-independent mechanisms, predominantly palbociclib-triggered metabolic and mitochondrial stress. Loss of RB1 resulted in palbociclib resistance, while deletion of CDKN2A or overexpression of CDK4, and MYC genes did not change sensitivity to palbociclib. CONCLUSIONS: Our data strongly support investigation of the chemotherapy-free palbociclib and venetoclax combination as an innovative treatment strategy for post-ibrutinib MCL patients without RB1 deletion.
Ibrutinib revolutionized therapy for relapsed/refractory (R/R) mantle cell lymphoma (MCL). Real-world data on the outcome of unselected patients are still limited. We analyzed 77 R/R MCL patients receiving ibrutinib with at least one prior systemic anti-lymphoma therapy. After a median follow-up of 14.0 months, 56 patients relapsed/progressed, and 45 died. The overall response rate was 66%, with 31% of complete metabolic remissions on PET/CT. The median progression-free and overall survival (OS) rates were 10.3 and 23.1 months, respectively. The median OS from ibrutinib failure was 3.7 months. High proliferation rate by Ki67 (≥ 30%) and two or more previous therapy lines both negatively correlated with outcome (HR = 2.2, p = 0.04, and HR = 2.06, p = 0.08, respectively). Female gender borderline correlated with better outcome (HR = 0.53, p = 0.08). In multivariate analysis, Ki67 and response to ibrutinib both correlated with OS (p < 0.05). Importantly, ibrutinib appeared to better control nodal and extranodal lymphoma than bone marrow (BM) involvement. From 20 patients with detectable BM infiltration (before ibrutinib initiation) achieving complete (n = 13) or partial (n = 7) metabolic remission, none achieved remission in BM. We confirmed good efficacy of ibrutinib in unselected heavily pre-treated MCL patients. Our findings support the use of a combination of ibrutinib and rituximab in patients with BM involvement.
- MeSH
- antigen Ki-67 MeSH
- dospělí MeSH
- lidé MeSH
- lymfom z plášťových buněk * patologie MeSH
- PET/CT MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- Geografické názvy
- Česká republika MeSH
Our knowledge of genetic aberrations, that is, variants and copy number variations (CNVs), associated with mantle cell lymphoma (MCL) relapse remains limited. A cohort of 25 patients with MCL at diagnosis and the first relapse after the failure of standard immunochemotherapy was analyzed using whole-exome sequencing. The most frequent variants at diagnosis and at relapse comprised six genes: TP53, ATM, KMT2D, CCND1, SP140, and LRP1B. The most frequent CNVs at diagnosis and at relapse included TP53 and CDKN2A/B deletions, and PIK3CA amplifications. The mean count of mutations per patient significantly increased at relapse (n = 34) compared to diagnosis (n = 27). The most frequent newly detected variants at relapse, LRP1B gene mutations, correlated with a higher mutational burden. Variant allele frequencies of TP53 variants increased from 0.35 to 0.76 at relapse. The frequency and length of predicted CNVs significantly increased at relapse with CDKN2A/B deletions being the most frequent. Our data suggest, that the resistant MCL clones detected at relapse were already present at diagnosis and were selected by therapy. We observed enrichment of genetic aberrations of DNA damage response pathway (TP53 and CDKN2A/B), and a significant increase in MCL heterogeneity. We identified LRP1B inactivation as a new potential driver of MCL relapse.
- MeSH
- dospělí MeSH
- geny p16 MeSH
- klonální evoluce genetika MeSH
- lidé MeSH
- lokální recidiva nádoru MeSH
- lymfom z plášťových buněk * diagnóza farmakoterapie genetika MeSH
- variabilita počtu kopií segmentů DNA MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem 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
- difúzní velkobuněčný B-lymfom * MeSH
- dospělí MeSH
- heterografty MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- myši MeSH
- nádorové mikroprostředí MeSH
- protinádorové látky * MeSH
- zvířata MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem 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
- difúzní velkobuněčný B-lymfom * genetika MeSH
- dospělí MeSH
- imunohistochemie MeSH
- lidé MeSH
- myši MeSH
- nádorové mikroprostředí genetika MeSH
- protinádorové látky * MeSH
- zvířata MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- cyklofosfamid aplikace a dávkování MeSH
- dospělí MeSH
- doxorubicin aplikace a dávkování MeSH
- lidé středního věku MeSH
- lidé MeSH
- lymfom z plášťových buněk * farmakoterapie genetika mortalita MeSH
- míra přežití MeSH
- mutace * MeSH
- nádorový supresorový protein p53 genetika MeSH
- prednison aplikace a dávkování MeSH
- přežití bez známek nemoci MeSH
- protokoly protinádorové kombinované chemoterapie aplikace a dávkování MeSH
- retrospektivní studie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- vinkristin aplikace a dávkování MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- dopisy MeSH
- práce podpořená grantem 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.
- Publikační typ
- časopisecké články MeSH
Cyclin-dependent kinases are therapeutic targets frequently deregulated in various cancers. By convenient alkylation of the 5-sulfanyl group, we synthesized 3-isopropyl-7-[4-(2-pyridyl)benzyl]amino-1(2) H-pyrazolo[4,3- d]pyrimidines with various substitutions at position 5 with potent antiproliferative activity in non-Hodgkin lymphoma cell lines. The most potent derivative 4.35 also displayed activities across more than 60 cancer cell lines. The kinase profiling confirmed high selectivity of 4.35 toward cyclin-dependent kinases (CDKs) 2, 5, and 9, and the cocrystal with CDK2/cyclin A2 revealed its binding in the active site. Cultured lymphoma cell lines treated with 4.35 showed dephosphorylation of CDK substrates, cleavage of PARP-1, downregulation of XIAP and MCL-1, and activation of caspases, which collectively confirmed ongoing apoptosis. Moreover, 4.35 demonstrated significant activity in various cell line xenograft and patient-derived xenograft mouse models in vivo both as a monotherapy and as a combination therapy with the BCL2-targeting venetoclax. These findings support further studies of combinatorial treatment based on CDK inhibitors.
- MeSH
- apoptóza účinky léků MeSH
- bicyklické sloučeniny heterocyklické farmakologie MeSH
- cyklin-dependentní kinasy antagonisté a inhibitory MeSH
- inhibitory proteinkinas chemická syntéza farmakologie terapeutické užití MeSH
- lidé MeSH
- lymfom farmakoterapie MeSH
- molekulární struktura MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- proliferace buněk účinky léků MeSH
- protinádorové látky chemická syntéza farmakologie terapeutické užití MeSH
- pyrazoly chemická syntéza farmakologie terapeutické užití MeSH
- pyrimidiny chemická syntéza farmakologie terapeutické užití MeSH
- sulfonamidy farmakologie MeSH
- synergismus léků MeSH
- vztahy mezi strukturou a aktivitou MeSH
- xenogenní modely - testy protinádorové aktivity MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In this study, we report the in vivo anti-lymphoma efficacy and diagnostic potential of newly designed near-infrared fluorescent dye containing polymer-doxorubicin conjugates using murine models of malignant lymphomas including one cell line-derived xenograft (RAJI) and two patient-derived lymphoma xenografts (VFN-D1 and VFN-M2). Two types of passively targeted conjugates differing in architecture of the polymer backbone were synthesized. One of the conjugates was designed using a single linear polymer chain, and the second was more sophisticated with a star-shaped high-molecular-weight (HMW) polymer employing a dendrimer core. The linear HPMA copolymers were linked to the dendrimer core via a one-point attachment, thus forming a hydrophilic polymer shell. Both polymer-doxorubicin conjugates were long-circulating with reduced side effects. Both polymer prodrugs were designed as stimuli-sensitive systems in which the anti-cancer drug doxorubicin was attached to the hydrophilic copolymers via a pH-labile hydrazone linkage. Such polymer prodrugs were fairly stable in aqueous solutions at pH 7.4, and the drug was readily released in mildly acid environments at pH 5-6.5 by hydrolysis of the hydrazone bonds. In addition, polymers were labelled with near-infrared fluorescent dye enabling long term in vivo visualization. Malignant lymphomas represent the most common type of haematological malignancies. Therapy for the majority of malignant lymphomas consists of multi-agent chemotherapy based on an anthracycline doxorubicin, the most prominent side effect of which is cardiotoxicity. We have demonstrated significant anti-lymphoma efficacy of the polymer-doxorubicin conjugates when compared to equally toxic doses of conventional (unbound) doxorubicin in all tested models. Favourable pharmacokinetics for carried drug and labelled polymer carrier was observed, showing predominant uptake of the drug and polymer itself in the tumour mass. In addition, we have observed a promising diagnostic potential of fluorescently labelled polymer prodrugs. Dynamically analyzed fluorescence intensity over subcutaneously xenografted lymphomas closely corresponded to changes in the lymphoma tumour volumes, thereby enabling a non-invasive assessment of treatment efficacy.
- MeSH
- akrylamidy chemie MeSH
- dendrimery chemie MeSH
- doxorubicin chemie terapeutické užití MeSH
- fluorescenční barviva chemie MeSH
- heterografty MeSH
- hydrazony chemie MeSH
- hydrofobní a hydrofilní interakce MeSH
- koncentrace vodíkových iontů MeSH
- lidé MeSH
- lymfom diagnostické zobrazování farmakoterapie patologie MeSH
- methakryláty chemie MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nanokapsle chemie MeSH
- polymerizace MeSH
- polymery chemie MeSH
- protinádorové látky chemie terapeutické užití MeSH
- uvolňování léčiv MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
