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1.
Br J Haematol ; 204(2): 487-491, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37669920

RESUMO

We analysed COVID-19 infection outcomes of 129/241 chronic lymphocytic leukaemia (CLL) (53.9%) and 22/55 monoclonal B-lymphocytosis (MBL) (40.0%) patients following multiple vaccine doses aiming for maximum measured anti-spike antibody response. Throughout the pandemic to date, there were 8/129 CLL (6.2%) patients hospitalised, with one death (0.8%). No MBL patients were hospitalised or died. CLL patients with COVID-19 had lower anti-spike levels (3778.8 AU/mL) than those without (13 486.8 AU/mL; p = 0.0061). Anti-nucleocapsid antibody was detected in 29.8% within 2 months and 17.5% >6 months. Of COVID-19-infected CLL patients, 47.3% received anti-viral therapy. A multiple vaccine dosing strategy to achieve measured maximum antibody is highly effective in preventing severe COVID-19.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Linfocitose , Vacinas , Humanos , Linfócitos B , Vacinas contra COVID-19 , Formação de Anticorpos , Vacinação
2.
Blood ; 140(25): 2709-2721, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36206503

RESUMO

Patients with chronic lymphocytic leukemia (CLL) or monoclonal B-lymphocytosis (MBL) have impaired response to COVID-19 vaccination. A total of 258 patients (215 with CLL and 43 with MBL) had antispike antibody levels evaluable for statistical analysis. The overall seroconversion rate in patients with CLL was 94.2% (antispike antibodies ≥50 AU/mL) and 100% in patients with MBL after multiple vaccine doses. After 3 doses (post-D3) in 167 patients with CLL, 73.7% were seropositive, 17.4% had antispike antibody levels between 50 and 999 AU/mL, and 56.3% had antispike antibody levels ≥1000 AU/mL, with a median rise from 144.6 to 1800.7 AU/mL. Of patients who were seronegative post-D2, 39.7% seroconverted post-D3. For those who then remained seronegative after their previous dose, seroconversion occurred in 40.6% post-D4, 46.2% post-D5, 16.7% post-D6, and 0% after D7 or D8. After seroconversion, most had a progressive increase in antispike antibody levels. Neutralization was associated with higher antispike antibody levels, more vaccine doses, and earlier severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants; neutralizing antibody against early clade D614G was detected in 65.3%, against Delta in 52.0%, and against Omicron in 36.5%. SARS-CoV-2-specific T-cell production of interferon γ and interleukin 2 occurred in 73.9% and 60.9%, respectively, of 23 patients tested. After multiple vaccine doses, by multivariate analysis, immunoglobulin M ≥0.53 g/L, immunoglobulin subclass G3 ≥0.22 g/L and absence of current CLL therapy were independent predictors of positive serological responses. Multiple sequential COVID-19 vaccination significantly increased seroconversion and antispike antibody levels in patients with CLL or MBL.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Linfocitose , Humanos , Vacinas contra COVID-19 , Leucemia Linfocítica Crônica de Células B/terapia , Soroconversão , COVID-19/prevenção & controle , SARS-CoV-2 , Imunoglobulina M , Imunoglobulina G , Imunidade , Anticorpos Antivirais
3.
Br J Haematol ; 197(1): 41-51, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34962656

RESUMO

Chronic lymphocytic leukaemia (CLL) is associated with immunocompromise and high risk of severe COVID-19 disease and mortality. Monoclonal B-cell lymphocytosis (MBL) patients also have immune impairment. We evaluated humoural and cellular immune responses in 181 patients with CLL (160) and MBL (21) to correlate failed seroconversion [<50 AU/ml SARS-CoV-2 II IgG assay, antibody to spike protein; Abbott Diagnostics)] following each of two vaccine doses with clinical and laboratory parameters. Following first and second doses, 79.2% then 45% of CLL, and 50% then 9.5% of MBL patients respectively remained seronegative. There was significant association between post dose two antibody level with pre-vaccination reduced IgM (p < 0.0001), IgG2 (p < 0.035), and IgG3 (p < 0.046), and CLL therapy within 12 months (p < 0.001) in univariate analysis. By multivariate analysis, reduced IgM (p < 0.0002) and active therapy (p < 0.0002) retained significance. Anti-spike protein levels varied widely and were lower in CLL than MBL patients, and both lower than in normal donors. Neutralisation activity showed anti-spike levels <1000 AU/ml were usually negative for both an early viral clade and the contemporary Delta variant and 72.9% of CLL and 53.3% of MBL failed to reach levels ≥1000 AU/ml. In a representative sample, ~80% had normal T-cell responses. Failed seroconversion occurred in 36.6% of treatment-naïve patients, in 78.1% on therapy, and in 85.7% on ibrutinib.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Linfocitose , Linfócitos B , Vacinas contra COVID-19 , Humanos , Imunidade Celular , Leucemia Linfocítica Crônica de Células B/complicações , Linfocitose/complicações , SARS-CoV-2
4.
Biomed Eng Online ; 20(1): 80, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362382

RESUMO

BACKGROUND: Knee osteoarthritis (KOA) is a common cause of disability among the elderly. We aimed to explore the effects of aldehyde dehydrogenase (ALDH) 2 on the progression of KOA and identifying the potential mechanisms. METHODS: First, ALDH2 expression in knee joint effusion of patients with KOA and the levels of oxidative stress-related markers were determined. After ALDH2 overexpression in monosodium iodoacetate (MIA)-treated SW1353 cells, cell viability was tested with CCK-8 assay. Subsequently, oxidative stress and inflammation-associated factors were measured. Meanwhile, cell apoptosis was assessed with TUNEL staining and expression of apoptosis-related proteins was detected by western blotting. To analyze the mechanism of ALDH2 in KOA, aquaporin 4 (AQP4) expression was determined using western blotting following ALDH2-upregulation. Subsequently, AQP4 was overexpressed to evaluate the changing of oxidative stress, inflammation and apoptosis in SW1353 cells exposed to MIA with ALDH2 overexpression. RESULTS: Results indicated that knee joint effusion with higher ALDH2 expression displayed lower oxidative stress. In addition, significantly upregulated ALDH2 expression was observed in MIA-treated SW1353 cells. ALDH2 overexpression oxidative stress, inflammation and apoptosis in SW1353 cells exposed to MIA. Moreover, MIA-triggered elevated expression of AQP4, which was reduced by ALDH2 overexpression. By contrast, AQP4-upregulation abrogated the inhibitory effects of ALDH2 on oxidative stress, inflammation and apoptosis in MIA-induced SW1353 cells. CONCLUSIONS: ALDH2 inactivates the expression of AQP4, by which mechanism the MIA-induced oxidative stress, inflammation and apoptosis injuries were alleviated, which provides a novel insight for understanding the mechanism of KOA and a promising target for the treatment of this disease.


Assuntos
Aquaporina 4 , Condrócitos , Idoso , Aldeído-Desidrogenase Mitocondrial/genética , Aldeído-Desidrogenase Mitocondrial/metabolismo , Apoptose , Aquaporina 4/genética , Humanos , Inflamação/induzido quimicamente , Ácido Iodoacético/toxicidade , Estresse Oxidativo
5.
Knee Surg Sports Traumatol Arthrosc ; 28(1): 270-280, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31422424

RESUMO

PURPOSE: To analyze the current randomized controlled trials (RCTs) of dynamic fixations (DFs) and static fixations (SFs) in treating distal tibiofibular syndesmosis injuries (DTSIs). METHODS: The Cochrane Central Register of Controlled Trials, PubMed, and EMBASE were systematically searched according to the PRISMA guidelines to identify RCTs comparing the DFs and SFs for DTSIs. Included studies were assessed using the Cochrane Risk of Bias Tool. Postoperative functional scores, range of motion (ROM), complication rate, and incidence of reoperation were statistically analyzed using review manager software, and a p value of < 0.05 was considered statistically significant. RESULTS: Five RCTs with a total of 282 patients were included. Analysis revealed statistically significant differences in favor of DFs with regard to American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score at a follow-up less than 6 months (MD 5.29; 95% CI 0.99-9.59; p = 0.02; I2 = 0%) and at a follow-up more than 2 years (MD 7.53; 95% CI 3.30-11.76; p = 0.0005; I2 = 0%), Olerud-Molander ankle (OMA) score at 1 year follow-up (MD 4.62; 95% CI 0.91-8.32; p = 0.01; I2 = 14%), and overall postoperative complication rate (RR 0.22; 95% CI 0.07-0.77; p = 0.02; I2 = 73%). There was no significant difference between the DFs and SFs regarding ROM and incidence of reoperation. CONCLUSIONS: The DF procedure leads to significantly improved functional scores as well as lower rate of overall postoperative complications when compared with SF procedure. On the basis of results of this meta-analysis, the DF should be recommended for managing the DTSI. LEVEL OF EVIDENCE: I.


Assuntos
Traumatismos do Tornozelo/cirurgia , Articulação do Tornozelo/cirurgia , Ligamentos Laterais do Tornozelo/cirurgia , Procedimentos Ortopédicos/métodos , Complicações Pós-Operatórias/etiologia , Parafusos Ósseos , Humanos , Procedimentos Ortopédicos/efeitos adversos , Ortopedia , Período Pós-Operatório , Ensaios Clínicos Controlados Aleatórios como Assunto , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Reoperação , Técnicas de Sutura , Resultado do Tratamento
6.
Med Sci Monit ; 25: 1314-1322, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30776287

RESUMO

BACKGROUND Ankle sprains with distal tibiofibular syndesmosis injuries (DTSIs) require anatomic reduction and fixation to restore the normal biomechanics of the ankle joint. In the last decade, dynamic fixation (DF) for DTSIs using a suture-button device has gained popularity because of its advantages over static fixation (SF). MATERIAL AND METHODS The present meta-analysis was conducted to compare clinical outcomes between DF and SF of DTSIs. PubMed, Cochrane Central Register of Controlled Trials, and Embase were systematically searched. Three randomized controlled studies and 7 cohort studies, with a total of 420 patients, were involved in this study. DTSIs patients treated with DF were assigned to the experimental group, and patients treated with SF were assigned to the control group. Outcomes were evaluated and analyzed by using review-manager software. Mean difference (MD) or risk ratio (RR) with 95% confidence interval (95% CI) was analyzed and calculated by utilizing the random effects models. RESULTS Analysis revealed no statistically significant differences between DF and SF in American Orthopedic Foot and Ankle Society Ankle-Hindfoot score (MD, 1.90; 95% CI, -0.23-4.03; p=0.08; I²=0%), Olerud-Molander score (MD, 1.92; 95% CI, -7.96-11.81; p=0.70; I²=55%), incidence of syndesmotic malreduction (RR, 0.19; 95% CI, 0.03-1.09; p=0.06; I²=0%), and overall postoperative complication rate (RR, 0.30; 95% CI, 0.09-0.99; p=0.05, I²=75%). The rate of second procedure was significantly lower compared with DF (RR, 0.17; 95% CI, 0.07-0.43; p=0.0002, I²=54%). CONCLUSIONS The dynamic fixation and static fixation methods are equal in clinical outcomes, with dynamic fixation needing fewer second interventions for DTSIs.


Assuntos
Traumatismos do Tornozelo/cirurgia , Articulação do Tornozelo/cirurgia , Fixação Interna de Fraturas/métodos , Adulto , Parafusos Ósseos , China , Feminino , Humanos , Masculino , Resultado do Tratamento
7.
Acta Orthop ; 90(4): 394-400, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30942136

RESUMO

Background and purpose - Artificial intelligence has rapidly become a powerful method in image analysis with the use of convolutional neural networks (CNNs). We assessed the ability of a CNN, with a fast object detection algorithm previously identifying the regions of interest, to detect distal radius fractures (DRFs) on anterior-posterior (AP) wrist radiographs. Patients and methods - 2,340 AP wrist radiographs from 2,340 patients were enrolled in this study. We trained the CNN to analyze wrist radiographs in the dataset. Feasibility of the object detection algorithm was evaluated by intersection of the union (IOU). The diagnostic performance of the network was measured by area under the receiver operating characteristics curve (AUC), accuracy, sensitivity, specificity, and Youden Index; the results were compared with those of medical professional groups. Results - The object detection model achieved a high average IOU, and none of the IOUs had a value less than 0.5. The AUC of the CNN for this test was 0.96. The network had better performance in distinguishing images with DRFs from normal images compared with a group of radiologists in terms of the accuracy, sensitivity, specificity, and Youden Index. The network presented a similar diagnostic performance to that of the orthopedists in terms of these variables. Interpretation - The network exhibited a diagnostic ability similar to that of the orthopedists and a performance superior to that of the radiologists in distinguishing AP wrist radiographs with DRFs from normal images under limited conditions. Further studies are required to determine the feasibility of applying our method as an auxiliary in clinical practice under extended conditions.


Assuntos
Inteligência Artificial , Fraturas do Rádio/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Aprendizado Profundo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Curva ROC , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Sensibilidade e Especificidade , Traumatismos do Punho/diagnóstico , Traumatismos do Punho/diagnóstico por imagem , Adulto Jovem
8.
Br J Haematol ; 182(3): 360-372, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29767411

RESUMO

The survival and proliferation of chronic lymphocytic leukaemia (CLL) cells is driven by multiple signalling pathways, including those mediated by the B cell, Toll-like and chemokine receptors. Many of these pathways converge on the same signalling molecules, including those involved in the Raf-1/MEK/Erk1/2-MAPK pathway. We investigated the effects of the MEK1/2 (also termed MAP2K1/2) inhibitor, binimetinib, against CLL cells cultured under conditions that mimic aspects of the tumour microenvironment. Binimetinib blocked CLL cell survival induced by stroma-conditioned media and phorbol myristylate (PMA). Binimetinib was also significantly more toxic towards CLL cells cultured in the presence of either anti-IgM antibody or stroma-derived factor-1α (SDF-1α) and reduced CLL cell cycle progression and proliferation. Furthermore, binimetinib significantly increased the sensitivity of CLL cells co-cultured with CD40 ligand (CD40L)-expressing fibroblasts to the BH3-mimetics ABT-737 and Venetoclax (ABT-199) via a mechanism involving down-regulation of Mcl-1 (MCL1) activity and Bim (BCL2L11) and Bcl-xL (BCL2L1) expression. Collectively, these data suggest that binimetinib may have both cytotoxic and cytostatic effects on CLL cells by blocking microenvironment-derived signals known to drive survival and proliferation. The combination of binimetinib with a BH3 mimetic may be an effective treatment strategy for CLL, particularly against the proliferative fraction of the disease within the tumour microenvironment.


Assuntos
Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Leucemia Linfocítica Crônica de Células B/patologia , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Microambiente Tumoral/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Compostos de Bifenilo/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Avaliação Pré-Clínica de Medicamentos/métodos , Sinergismo Farmacológico , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nitrofenóis/farmacologia , Piperazinas/farmacologia , Sulfonamidas/farmacologia , Células Tumorais Cultivadas
9.
Br J Haematol ; 182(5): 654-669, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29978459

RESUMO

Despite significant advances in treatment, chronic lymphocytic leukaemia (CLL) remains an incurable disease. Ibrutinib and idelalisib, which inhibit Bruton Tyrosine kinase (BTK) and phosphoinositol-3 (PI3) kinase-δ respectively, have become important treatment options for the disease and demonstrate the potential of targeting components of the B-cell receptor-signalling pathway. IBL-202 is a dual inhibitor of the PIM and PI3 kinases. Synergy between the pan-PIM inhibitor, pPIMi, and idelalisib against a range of haematological cell lines and primary CLL cells supports the rationale for preclinical studies of IBL-202 in CLL. Importantly, IBL-202, but not idelalisib, was cytotoxic against CLL cells under in vitro conditions that mimic the hypoxic tumour microenvironment. The significant effects of IBL-202 on CD49d and CXCR4 expression and migration, cycle and proliferation of CLL cells suggest the drug may also interfere with the migratory and proliferative capacity of the leukaemic cells. Collectively, these data demonstrate that dual inhibition of the PIM and PI3 kinases by IBL-202 may be an effective strategy for targeting CLL cells, particularly within the environmental niches known to confer drug-resistance.


Assuntos
Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Integrina alfa4/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Purinas/uso terapêutico , Quinazolinonas/uso terapêutico , Receptores de Antígenos de Linfócitos B/metabolismo , Receptores CXCR4/metabolismo , Células Tumorais Cultivadas , Microambiente Tumoral
11.
J Foot Ankle Surg ; 56(4): 827-831, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28633786

RESUMO

Tumors rarely metastasize to the foot bones; however, a misdiagnosis can lead to a poor outcome. These metastatic tumors can cause foot pain and other symptoms in patients who are asymptomatic for the primary tumor. To accurately diagnose acrometastases, the attending physician must have a high index of suspicion and conduct a thorough examination and appropriate diagnostic testing. We present a rare case of metastatic pulmonary adenocarcinoma of the talus, which was initially misdiagnosed as a benign bone cyst. After pulmonary adenocarcinoma was diagnosed, the patient received multidrug treatment for the primary and metastatic lesions and was still responding well at the 12-month follow-up visit.


Assuntos
Adenocarcinoma/terapia , Neoplasias Ósseas/terapia , Neoplasias Pulmonares/terapia , Tálus/patologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/secundário , Adenocarcinoma de Pulmão , Idoso , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Masculino
12.
Leuk Lymphoma ; 65(5): 585-597, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38227293

RESUMO

Despite advances in treatment, a significant proportion of patients with chronic lymphocytic leukemia (CLL) will relapse with drug-resistant disease. The imipridones, ONC-201 and ONC-212, are effective against a range of different cancers, including acute myeloid leukemia (AML) and tumors of the brain, breast, and prostate. These drugs induce cell death through activation of the mitochondrial protease, caseinolytic protease (CIpP), and the unfolded protein response (UPR). Here we demonstrate that the novel imipridone analog, TR-57, has efficacy as a single agent and synergises with venetoclax against CLL cells under in vitro conditions that mimic the tumor microenvironment. Changes in protein expression suggest TR-57 activates the UPR, inhibits the AKT and ERK1/2 pathways and induces pro-apoptotic changes in the expression of proteins of the BCL-2 family. The study suggests that TR-57, as a single agent and in combination with venetoclax, may represent an effective treatment option for CLL.


Assuntos
Apoptose , Compostos Bicíclicos Heterocíclicos com Pontes , Sinergismo Farmacológico , Leucemia Linfocítica Crônica de Células B , Sulfonamidas , Humanos , Sulfonamidas/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Transdução de Sinais/efeitos dos fármacos
13.
Leuk Lymphoma ; 63(12): 2795-2806, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35767361

RESUMO

Since first described almost two decades ago, there has been significant evolution in our definition and understanding of the biology and implications of monoclonal B-cell lymphocytosis (MBL). This review provides an overview of the definition, classification, biology, and natural history of MBL, mainly focused on the dominant CLL-like phenotype form of MBL. The increasingly recognized implications of MBL with respect to immune dysfunction are discussed, particularly in view of the COVID-19 pandemic, along with management recommendations for MBL in the clinic.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Linfocitose , Neoplasias de Plasmócitos , Lesões Pré-Cancerosas , Humanos , Linfocitose/diagnóstico , Linfocitose/etiologia , Linfocitose/terapia , Pandemias , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/terapia , Leucemia Linfocítica Crônica de Células B/epidemiologia , Linfócitos B , COVID-19/diagnóstico , Biologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-34738868

RESUMO

In mammals, AMPylation of cellular proteins is carried out by Huntingtin yeast-interacting protein E, and pseudokinase SelO. Lysates from mouse B16-F10 melanoma cells have been fractionated by immuno-precipitation using magnetic Dynabeads coated with antibodies against both adenosine 5'-monophosphate in phosphate ester linkage to tyrosine, and adenosine-phosphate. Proteins pulled down with both these antibodies were subject to post-translational modification, most likely AMPylation. Using tandem mass spectrometry, analysis of these protein fractions identified 333 proteins that could be pulled down by both antibodies. Many of these proteins clustered in 13 functional Ingenuity Pathway Analysis categories of 4 or more adenylated proteins including some from the cytoskeleton, and some involved with initiating the unfolded protein response.Supplemental data for this article is available online at https://doi.org/10.1080/15257770.2021.1995608 .


Assuntos
Melanoma , Processamento de Proteína Pós-Traducional , Monofosfato de Adenosina/metabolismo , Animais , Mamíferos/metabolismo , Camundongos
15.
Artigo em Inglês | MEDLINE | ID: mdl-34886743

RESUMO

Triple combination FCR (fludarabine, cyclophosphamide and rituximab) is often used as front-line treatment for chronic lymphocytic leukemia (CLL) and non-Hodgkin's lymphoma. Results from our laboratory indicate that 2-FaraAMP (fludarabine) has multiple mechanisms of cytotoxicity that include accumulation of isoforms and phosphorylated derivatives of p53, and induction of the unfolded protein response (UPR). Using protein pull-downs with Dynabeads coated with p53 antibody, we have found that 2-FaraA (fludarabine nucleoside) induces major changes in the p53 interactome in human Raji lymphoma and IM9 multiple myeloma cells. These changes are likely driven by DNA strand breaks induced by 2-FaraA that activate protein kinases such as ATM, ATR and Chk1.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Linhagem Celular , Ciclofosfamida , Humanos , Neoplasias/tratamento farmacológico , Nucleosídeos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Vidarabina/análogos & derivados , Vidarabina/farmacologia
16.
EJHaem ; 3(1): 129-138, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35846218

RESUMO

Chronic lymphocytic leukaemia (CLL) is invariably accompanied by some degree of immune failure, and CLL patients have a high rate of second primary malignancy (SPM) compared to the general population. We comprehensively documented the incidence of all forms of SPM including skin cancer (SC), solid organ malignancy (SOM), second haematological malignancy (SHM) and separately Richter's syndrome (RS) across all therapy eras. Among the 517 CLL/small lymphocytic lymphoma (SLL) patients, the overall incidence of SPMs with competing risks was SC 31.07%, SOM 25.99%, SHM 5.19% and RS 7.55%. Of the 216 treated patients, 106 (49.1%) had at least one form of SPM, and 63 of 106 (29.2% of treated patients) developed an SPM 1.5 years (median) after treatment for their CLL. Melanoma accounted for 30.3% of SC. Squamous cell carcinoma (SCC), including eight metastatic SCCs, was 1.8 times more than basal cell carcinoma (BCC), a reversal of the typical BCC:SCC ratio. The most common SOMs were prostate (6.4%) and breast (4.5%). SHM included seven acute myeloid leukaemia (AML) and five myelodysplasia (MDS) of which eight (four AML, four MDS) were therapy-related. Any SPM occurred in 32.1% of 53 Monoclonal B-lymphocytosis (MBL) patients. Age-adjusted standardised rates of SPM (per 100,000) for CLL, MBL and the general Australian population were 2648, 1855 and 486.9, respectively. SPMs are a major health burden with 44.9% of CLL patients with having at least one SPM, and apart from SC, associated with significantly reduced overall survival. Dramatic improvements in CLL treatment and survival have occurred with immunochemotherapy and targeted therapies, but mitigating SPM burden will be important to sustain further progress.

17.
EJHaem ; 2(1): 81-93, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35846080

RESUMO

Despite advances in therapy, a significant proportion of patients with chronic lymphocytic leukemia (CLL) relapse with drug resistant disease. Novel treatment approaches are required, particularly for high risk disease. The imipridones represent a new class of cancer therapy that has been investigated in pre-clinical and clinical trials against a range of different cancers. We investigated the effects of the imipridone, ONC-212, against CLL cells cultured under conditions that mimic aspects of the tumour microenvironment and a TP53ko CLL cell line (OSU-CLL-TP53ko). ONC-212 induced dose-dependent apoptosis, cell cycle arrest and reduced the migration of CLL cells in vitro, including cells from patients with TP53 lesions and OSU-CLL-TP53ko cells. The effects of ONC-212 were associated with protein changes consistent with activation of the mitochondrial protease, CIpP, and the integrated stress response. We also observed inhibition of pathways downstream of the B-cell receptor (BCR) (AKT and MAPK-ERK1/2) and a pro-apoptotic shift in the balance of proteins of the BCL2 family of proteins (BCL2, MCL1, BCLxL, BAX and NOXA). In conclusion, the study suggests ONC-212 may represent an effective treatment for high risk CLL disease by inhibiting multiple facets of the BCR signaling pathway and the pro-survival effects of the BCL2-family proteins.

18.
Blood Adv ; 4(20): 5093-5106, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33085757

RESUMO

The B-cell receptor signaling pathway and dysregulation of the Bcl-2 family of proteins play crucial roles in the pathogenesis of chronic lymphocytic leukemia (CLL). Despite significant advances in the treatment of the disease, relapse and drug resistance are not uncommon. In the current study, we investigated the dual PI3/PIM kinase inhibitor IBL-202 in combination with venetoclax as a treatment option for CLL using both primary CLL cells and TP53-deficient OSU-CLL cells generated using the CRISPR-Cas9 system. IBL-202 and venetoclax were highly synergistic against primary CLL cells cocultured with CD40L fibroblasts (combination index [CI], 0.4, at a fractional effect of 0.9) and TP53-knockout (KO) OSU-CLL cells (CI, 0.5, at a fractional effect of 0.9). Synergy between the drugs was consistent, with a significant (P < .05) reduction in the 50% inhibitory concentration for both drugs. IBL-202 and venetoclax in combination induced cell-cycle arrest and slowed the proliferation of both wild-type and TP53-KO cell lines. The drug combination inhibited AKT phosphorylation, reduced expression of Bcl-xL and NF-κB, and increased the Noxa/Mcl-1 ratio. Downregulation of CXCR4 was consistent with inhibition of the SDF-1α-induced migratory capacity of CLL cells. Synergy between IBL-202 and venetoclax against primary CLL cells cultured under conditions that mimic the tumor microenvironment suggests this drug combination may be effective against CLL cells within the lymph nodes and bone marrow. Furthermore, the efficacy of the combination against the TP53-KO OSU-CLL cell line suggests the combination may be a highly effective treatment strategy for high-risk CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Sulfonamidas/farmacologia , Microambiente Tumoral
19.
Cancer Drug Resist ; 3(3): 532-549, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-35582439

RESUMO

The treatment of chronic lymphocytic leukaemia has been revolutionised in recent years, first by the introduction of chemoimmunotherapy regimens and subsequently by the development of drugs, including ibrutinib, idelalisib and venetoclax, that target components of the B-cell receptor signalling pathway or B-cell lymphoma 2 family of proteins. Despite high initial response rates in patients treated with chemoimmunotherapy or targeted agents, a significant proportion of patients relapse with progressive and refractory disease. In a subset of these patients, drug resistance has been associated with specific genetic lesions or activation of alternate pro-survival pathways. However, the mechanisms that confer drug resistance in the remainder of the patients with refractory disease have yet to be fully elucidated. In this review, we discuss our current understanding of the mechanics of drug resistance in chronic lymphocytic leukaemia and describe how this knowledge may aid in rationalising future treatment strategies to prevent the development of refractory or aggressive transformation of the disease.

20.
Leuk Lymphoma ; 61(8): 1810-1822, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32249639

RESUMO

Fatty acid synthesis is crucial in supporting the survival and proliferation of multiple forms of cancer. The high metabolic demands of fatty acid synthesis are regulated by the AMP-activated kinase and activity of the fatty acid synthase enzyme. In this study, the roles of these enzymes in diffuse large B-cell lymphoma (DLBCL) were investigated by genetic knock-down and pharmacological activation of AMP-activated kinase by metformin, and selective inhibition of fatty acid synthase using the novel drug Fasnall. We observed distinct heterogeneity and adaptive plasticity of lipid metabolism in a panel of DLBCL cell lines and demonstrate the therapeutic potential of inhibiting fatty acid synthesis in a subset of DLBCL cells. The translational relevance of these in vitro data is supported by the strong correlation between AMP-activated protein kinase expression in primary DLBCL samples and disease relapse. Inhibition of fatty acid synthase with Fasnall may represent a therapeutic option for DLBCL that preferentially subverts to de novo fatty acid synthesis.


Assuntos
Linfoma Difuso de Grandes Células B , Preparações Farmacêuticas , Monofosfato de Adenosina , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Ácido Graxo Sintases/genética , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Proteínas Quinases
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