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1.
Mol Microbiol ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193389

RESUMO

Trypanosoma cruzi, the etiological agent of Chagas disease is a protozoan parasite that infects phagocytic and non-phagocytic mammalian cells. At early stages of infection, trypomastigotes, the infective forms of this parasite, localize in a vesicular compartment called the T. cruzi parasitophorous vacuole until the exit of parasites to the host cell cytoplasm where continue their infective cycle. Rab proteins participate in the membrane traffic's molecular machinery, functioning as central regulators of vesicle recognition and transport. In previous work, we demonstrated that endocytic Rabs are key factors of the T. cruzi infection process in non-phagocytic cells, regulating the formation and the maturation of the vacuole. In this work, we identified and characterized other molecular components of the vesicular transport pathways and their participation in the T. cruzi infection. We found that Rab9a and Rab32, two regulators of the endocytic and autophagic pathways, were actively recruited to the T. cruzi vacuoles and favored the late stages of the infective process. The recruitment was specific and dependent on T. cruzi protein synthesis. Interestingly, Rab32 association depends on the presence of Rab9a in the vacuolar membrane, while the inhibition of the cysteine-protease cruzipain, a T. cruzi virulence factor, significantly decreases both Rab9a and Rab32 association with the vacuole. In summary, this work showed for the first time that specific molecules produced and secreted by the parasite can subvert intracellular components of host cells to benefit the infection. These new data shed light on the complex map of interactions between T. cruzi and the host cell and introduce concepts that can be useful in finding new forms of intervention against this parasite in the future.

2.
Am J Hematol ; 98(4): 645-657, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36606708

RESUMO

Advances in molecular profiling of newly diagnosed diffuse large B-cell lymphoma (DLBCL) have recently refine genetic subgroups. Genetic subgroups remain undetermined at the time of relapse or refractory (RR) disease. This study aims to decipher genetic subgroups and search for prognostic molecular biomarkers in patients with RR-DLBCL. From 2015 to 2021, targeted next-generation sequencing analyses of germline-matched tumor samples and fresh tissue from RR-DLBCL patients were performed. Unsupervised clustering of somatic mutations was performed and correlations with patient outcome were sought. A number of 120 patients with RR-DLBCL were included in LNH-EP1 study and a molecular tumor landscape was successfully analyzed in 87% of patients (104/120 tumor samples). The median age was 67.5 years (range 27.4-87.4), median number of previous treatments was 2 (range 1-9). The most frequently mutated genes were TP53 (n = 53 mutations; 42% of samples), CREBBP (n = 39; 32%), BCL2 (n = 86; 31%), KMT2D (n = 39; 28%) and PIM1 (n = 54; 22%). Unsupervised clustering separated three genetic subgroups entitled BST (enriched in BCL2, SOCS1, and TNFRSF14 mutations); TKS (enriched in TP53, KMT2D, and STAT6 mutations); and PCM (enriched in PIM1, CD79B, and MYD88 mutations). Median overall survival (OS) was 11.0 (95% confidence interval [CI]: 8.1-12.6) months. OS was not significantly different between the three genetic subgroups. GNA13 mutant was significantly associated with an increased risk of death (hazard ratio: 6.6 [95% CI: 2.1-20.6]; p = .0011) and shorter OS (p = .0340). At the time of relapse or refractory disease, three genetic subgroups of DLBCL patients were delineated, which could help advance precision molecular medicine programs.


Assuntos
Linfoma Difuso de Grandes Células B , Recidiva Local de Neoplasia , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Prognóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Mutação , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas Proto-Oncogênicas c-bcl-2/genética , Biomarcadores
3.
Cancer ; 128(17): 3185-3195, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35737639

RESUMO

BACKGROUND: CC-90011 is an oral, potent, selective, reversible inhibitor of lysine-specific demethylase 1 (LSD1) that was well tolerated, with encouraging activity in patients who had advanced solid tumors or relapsed/refractory marginal zone lymphoma. The authors present long-term safety and efficacy and novel pharmacodynamic and pharmacokinetic data from the first-in-human study of CC-90011. METHODS: CC-90011-ST-001 (ClincalTrials.gov identifier NCT02875223; Eudract number 2015-005243-13) is a phase 1, multicenter study in which patients received CC-90011 once per week in 28-day cycles. The objectives were to determine the safety, maximum tolerated dose, and/or recommended phase 2 dose (primary) and to evaluate preliminary efficacy and pharmacokinetics (secondary). RESULTS: Sixty-nine patients were enrolled, including 50 in the dose-escalation arm and 19 in the dose-expansion arm. Thrombocytopenia was the most common treatment-related adverse event and was successfully managed with dose modifications. Clinical activity with prolonged, durable responses were observed, particularly in patients who had neuroendocrine neoplasms. In the dose-escalation arm, one patient with relapsed/refractory marginal zone lymphoma achieved a complete response (ongoing in cycle 58). In the dose-expansion arm, three patients with neuroendocrine neoplasms had stable disease after nine or more cycles, including one patient who was in cycle 46 of ongoing treatment. CC-90011 decreased levels of secreted neuroendocrine peptides chromogranin A, progastrin-releasing peptide, and RNA expression of the blood pharmacodynamic marker monocyte-to-macrophage differentiation-associated. CONCLUSIONS: The safety profile of CC-90011 suggested that its reversible mechanism of action may provide an advantage over other irreversible LSD1 inhibitors. The favorable tolerability profile, clinical activity, durable responses, and once-per-week dosing support further exploration of CC-90011 as monotherapy and in combination with other treatments for patients with advanced solid tumors and other malignancies.


Assuntos
Linfoma de Zona Marginal Tipo Células B , Neoplasias , Histona Desmetilases , Humanos , Dose Máxima Tolerável , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Compostos Orgânicos
4.
Oncologist ; 27(7): 536-e553, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35325211

RESUMO

BACKGROUND: Patients with KRAS-mutant cancers have limited treatment options. Here we present a phase I study of JNJ-74699157, an oral, selective, covalent inhibitor of the KRAS G12C isoform, in patients with advanced cancer harboring the KRAS G12C mutation. METHODS: Eligible patients (aged ≥18 years) who had previously received or were ineligible for standard treatment received JNJ-74699157 once daily on a 21-day cycle. Dose escalation was guided by a modified continual reassessment method. RESULTS: Ten patients (100 mg: 9 and 200 mg: 1) were enrolled. Tumor types included non-small cell lung cancer (n = 5), colorectal cancer (n = 4), and carcinoma of unknown primary site (n = 1). The median age was 65 (range: 36-74) years and median treatment duration was 2.91 (range: 0.5-7.5) months. Dose-limiting toxicities of grades 3-4 increased blood creatinine phosphokinase (CPK) were observed in 100 mg and 200 mg dose levels. The most common adverse event was increased blood CPK (6 patients). No significant clinical benefit was observed; the best response was stable disease in 4 patients (40%). CONCLUSION: Based on dose-limiting skeletal muscle toxicities and the lack of efficacy at the 100 mg dose, further enrollment was stopped. The safety profile of JNJ-74699157 was not considered favorable for further clinical development. CLINICALTRIALS.GOV IDENTIFIER: NCT04006301.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética
5.
Br J Cancer ; 123(8): 1235-1243, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32741971

RESUMO

BACKGROUND: This is the first-in-human study of novel anti-angiopoietin-2 (Ang-2) monoclonal antibody LY3127804 as monotherapy and in combination with ramucirumab in advanced solid tumours. METHODS: Patients received intravenous LY3127804 monotherapy (4, 8, 12, 16, 20 and 27 mg/kg) in part A; LY3127804 (8, 12, 16, 20 and 27 mg/kg) with 8 mg/kg ramucirumab in part B; and LY3127804 (20 mg/kg) with 12 mg/kg ramucirumab in part C. Treatments were administered every 2 weeks (Q2W) during 28-day cycles. Dose-escalation was based on cycle 1 dose-limiting toxicities (DLTs). RESULTS: Sixty-two patients were treated in part A (n = 20), part B (n = 35) and part C (n = 7). Constipation, diarrhoea and fatigue were the most common treatment-emergent adverse events (TEAEs) in part A; hypertension and peripheral oedema were the most frequent TEAE in parts B and C. No DLT was observed and maximum tolerated dose for LY3127804 was not reached. Four patients achieved partial response with combination therapy (clear cell endometrial carcinoma, cervix squamous cell carcinoma, carcinoma of unknown primary and gastroesophageal junction carcinoma), 29 achieved stable disease, and 24 had progressive disease. CONCLUSIONS: LY3127804 monotherapy and its combination with ramucirumab are well tolerated. LY3127804 20 mg/kg was the recommended Phase 2 dose.


Assuntos
Angiopoietina-2/antagonistas & inibidores , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ramucirumab
6.
Cell Mol Life Sci ; 76(7): 1397-1417, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30673822

RESUMO

Mitochondrial dysfunction represents an important cellular stressor and when intense and persistent cells must unleash an adaptive response to prevent their extinction. Furthermore, mitochondria can induce nuclear transcriptional changes and DNA methylation can modulate cellular responses to stress. We hypothesized that mitochondrial dysfunction could trigger an epigenetically mediated adaptive response through a distinct DNA methylation patterning. We studied cellular stress responses (i.e., apoptosis and autophagy) in mitochondrial dysfunction models. In addition, we explored nuclear DNA methylation in response to this stressor and its relevance in cell survival. Experiments in cultured human myoblasts revealed that intense mitochondrial dysfunction triggered a methylation-dependent pro-survival response. Assays done on mitochondrial disease patient tissues showed increased autophagy and enhanced DNA methylation of tumor suppressor genes and pathways involved in cell survival regulation. In conclusion, mitochondrial dysfunction leads to a "pro-survival" adaptive state that seems to be triggered by the differential methylation of nuclear genes.


Assuntos
Núcleo Celular/genética , Epigênese Genética , Mitocôndrias/metabolismo , Adolescente , Autofagia/efeitos dos fármacos , Estudos de Casos e Controles , Núcleo Celular/metabolismo , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Criança , Pré-Escolar , Metilação de DNA , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/patologia , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Rotenona/farmacologia
7.
Br J Cancer ; 119(8): 937-939, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30327567

RESUMO

BACKGROUND: Reliable evaluation of treatment benefit in early phase clinical trials is necessary. The time to progression ratio (TTPr), which compares successive TTP in a single patient, is a powerful criteria for determining targeted or immune therapies efficacy. METHODS: We evaluated 205 TTPr in a large cohort of 177 advanced cancer patients enrolled in at least two Phase 1/1b trials (out of 2827 phase 1/1b-treated patients) at Gustave Roussy. RESULTS: This first wide description of TTPr showed that, under the hypothesis of overall absence of treatment line effect, the median TTPr was 0.7 and that 25% of patients presented a TTPr above the conventional efficacy threshold of 1.3. CONCLUSIONS: A higher median TTPr and a larger proportion of patients above the 1.3 threshold should therefore be achieved to conclude to drug efficacy. New guidelines for TTPr interpretation and calibration are proposed, which warrant independent prospective validation.


Assuntos
Antineoplásicos/uso terapêutico , Ensaios Clínicos Fase I como Assunto/métodos , Progressão da Doença , Neoplasias/tratamento farmacológico , Resultado do Tratamento , Humanos
8.
Cell Microbiol ; 19(6)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27992096

RESUMO

Trypanosoma cruzi, the etiologic agent of Chagas disease, is an obligate intracellular parasite that exploits different host vesicular pathways to invade the target cells. Vesicular and target soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are key proteins of the intracellular membrane fusion machinery. During the early times of T. cruzi infection, several vesicles are attracted to the parasite contact sites in the plasma membrane. Fusion of these vesicles promotes the formation of the parasitic vacuole and parasite entry. In this work, we study the requirement and the nature of SNAREs involved in the fusion events that take place during T. cruzi infection. Our results show that inhibition of N-ethylmaleimide-sensitive factor protein, a protein required for SNARE complex disassembly, impairs T. cruzi infection. Both TI-VAMP/VAMP7 and cellubrevin/VAMP3, two v-SNAREs of the endocytic and exocytic pathways, are specifically recruited to the parasitophorous vacuole membrane in a synchronized manner but, although VAMP3 is acquired earlier than VAMP7, impairment of VAMP3 by tetanus neurotoxin fails to reduce T. cruzi infection. In contrast, reduction of VAMP7 activity by expression of VAMP7's longin domain, depletion by small interfering RNA or knockout, significantly decreases T. cruzi infection susceptibility as a result of a minor acquisition of lysosomal components to the parasitic vacuole. In addition, overexpression of the VAMP7 partner Vti1b increases the infection, whereas expression of a KIF5 kinesin mutant reduces VAMP7 recruitment to vacuole and, concomitantly, T. cruzi infection. Altogether, these data support a key role of TI-VAMP/VAMP7 in the fusion events that culminate in the T. cruzi parasitophorous vacuole development.


Assuntos
Membrana Celular/metabolismo , Fusão de Membrana/genética , Trypanosoma cruzi/metabolismo , Vacúolos/parasitologia , Proteína 3 Associada à Membrana da Vesícula/genética , Animais , Células CHO , Linhagem Celular , Doença de Chagas/parasitologia , Chlorocebus aethiops , Cricetulus , Células HeLa , Humanos , Cinesinas/genética , Cinesinas/metabolismo , Fusão de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Interferência de RNA , RNA Interferente Pequeno/genética , Trypanosoma cruzi/genética , Células Vero
9.
Breast J ; 24(4): 473-479, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29286192

RESUMO

The combination of Pegylated Liposomal Doxorubicin (PLD) plus Gemcitabine (GEM) has been previously investigated in the treatment of metastatic breast cancer (MBC). PLD is a doxorubicin formulation with prolonged circulation time and better tissue distribution. GEM is a nucleoside analog with nonoverlapping toxicity compared to PLD. The aim of our study was to assess efficacy, toxicity, and long-term outcome of this combination. Patients with heavily treated MBC were retrospectively analyzed. Chemotherapy consisted of PLD 25 mg/m2 and GEM 800 mg/m2 day 1, on a three-week schedule. Cardiac function was evaluated baseline and during treatment. Radiological response was graded according to RECIST criteria v1.1. Toxicity was scored according to CTCAE v4.0. Progression-free survival (PFS) and overall survival (OS) were evaluated. From 2001 to 2014, 122 pts were included. Median age was 55 (range: 28-84). Median previous treatment schedules in the metastatic scenario were 3 (range: 1-15). Most patients received prior anthracyclines (85%). Median number of metastatic sites was 2 (range: 1-7). Median number of cycles delivered was 5 (range: 1-36). Overall response rate was 31% (5% complete responses; 26% partial responses). Stable and progressive diseases were observed in 32% and 26% of patients. Grade ≥3 neutropenia was observed in 29 patients (24%). Grade ≥3 hand-foot syndrome was detected in 17 patients (14%), mostly since cycle 3 (88%). Median cumulative PLD dose was 125 mg/m2 . At a median follow-up of 101 months, median PFS and OS were 7 and 22 months, respectively. PLD-GEM combination achieves remarkable long-term outcomes with an acceptable toxicity profile in patients with MBC.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Desoxicitidina/análogos & derivados , Doxorrubicina/análogos & derivados , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Mama/mortalidade , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Estudos Prospectivos , Estudos Retrospectivos , Gencitabina
10.
Br J Cancer ; 115(6): 655-63, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27537382

RESUMO

BACKGROUND: The degree of histopathological response after neoadjuvant therapy in locally advanced gastric cancer (GC) is a key determinant of patients' long-term outcome. We aimed to assess the pattern of histopathological regression after two neoadjuvant approaches and its impact on survival times. METHODS: Regression grade of the primary tumour (Becker criteria) and the degree of nodal response by a 4-point scale (grades A-D) were assessed. Grade A-true negative lymph nodes (LNs); grade B and C-infiltrated LNs with any or little evidence of nodal response; and grade D-complete pathological response in a previously infiltrated LN. A favourable pathological response was defined as Becker Ia-b and grade D. RESULTS: From 2004 to 2014, 80 patients with GC (cT3-4/N+ by CT-scan/EUS) were treated with either preoperative chemotherapy (ChT, n=34) or chemoradiation (CRT, n=46). Patients in the CRT group had a higher likelihood of achieving a Becker Ia-b response (58 vs 32%, P=0.001), a grade D nodal regression (30 vs 6%, P=0.009) and a favourable pathological response (23 vs 3%; P=0.019). Patients with a grade D nodal response had a longer 5-year PFS and OS compared with those with a grade B or C response. Patients with a baseline negative LN status had similar outcomes irrespective of the preoperative therapy received (5-year OS; ChT vs CRT, 58 vs 51%, P=0.92). CONCLUSIONS: Preoperative chemoradiation increases the likelihood of achieving favourable histopathological features that correlate with a 5-year OS>70% in GC patients.


Assuntos
Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Terapia Neoadjuvante/métodos , Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Neoplasias Gástricas/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Adenocarcinoma/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Astenia/induzido quimicamente , Capecitabina/administração & dosagem , Intervalo Livre de Doença , Docetaxel , Feminino , Fluoruracila/administração & dosagem , Gastrectomia , Gastroenteropatias/induzido quimicamente , Doenças Hematológicas/induzido quimicamente , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Paclitaxel/administração & dosagem , Radioterapia Conformacional/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/terapia , Taxoides/administração & dosagem , Resultado do Tratamento
11.
Am J Obstet Gynecol ; 213(1): 51.e1-51.e8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25659466

RESUMO

OBJECTIVE: Chromosome 3q gain has been consistently observed in cervical intraepithelial neoplasia grades 2 and 3 (CIN 2,3) and squamous cell carcinomas of the cervix. There are a number of potential clinical uses of testing for 3q gain in liquid cytology specimens, including the identification of subsets of women with atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion cytology who are at greatest risk of having CIN 2,3 and would thus benefit most from immediate colposcopy. The objective of this study was to establish the sensitivity and specificity of 3q gain for discriminating between CIN 2,3 and normal. STUDY DESIGN: Residual cytology specimens were collected from 199 women. Liquid-based cytology (LBC) was used for the selection of subjects, with women with high-grade squamous intraepithelial lesion or high-grade squamous intraepithelial lesion who had colposcopy and adjudicated biopsy-confirmed CIN 2,3 forming the disease-positive group (n = 28) and women doubly negative for both cytology and high-risk human papillomavirus (hrHPV) testing forming the disease-negative group (n = 171). A single slide was prepared from each residual LBC specimen and analyzed for 3q gain by fluorescent in situ hybridization, using a probe specific for the 3q26 region and a control probe for the chromosome 7 centromere. Two approaches were compared for the determination of 3q gain. The first was based on the analysis of an entire cervical cytology slide for the presence of rare cells with a high copy number (>4 copies) for the 3q locus. The second approach was based on the analysis of 400 cells to determine the percentage with 3 or more copies of the 3q locus. RESULTS: Using the approach based on the detection of rare cells with a high copy number (>4 copies) for the 3q locus, 26 of the specimens from women with CIN 2,3 and none of the 171 specimens from women who were both hrHPV and cytology negative was positive for 3q gain. This translates to a sensitivity of 92.9% (95% confidence interval [CI], 76.5-98.9%), a specificity of 100% (95% CI, 97.8-100%), a positive predictive value of 100% (95% CI, 86.7-100%), and a negative predictive value of 98.8% (95% CI, 95.9-99.8), for distinguishing CIN 2,3 from normal. CONCLUSION: These data support the potential clinical use of 3q gain for the evaluation of women in a number of clinical situations, including women with atypical squamous cells of undetermined significance, low-grade squamous intraepithelial lesion, and those who are hrHPV positive.


Assuntos
Cromossomos Humanos Par 3/genética , Lesões Pré-Cancerosas/genética , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Algoritmos , Células Escamosas Atípicas do Colo do Útero , Sondas de DNA , Feminino , Dosagem de Genes , Humanos , Hibridização in Situ Fluorescente , Sensibilidade e Especificidade , Lesões Intraepiteliais Escamosas Cervicais/genética
12.
FEBS Lett ; 598(1): 140-166, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101809

RESUMO

Intracellular infections as well as changes in the cell nutritional environment are main events that trigger cellular stress responses. One crucial cell response to stress conditions is autophagy. During the last 30 years, several scenarios involving autophagy induction or inhibition over the course of an intracellular invasion by pathogens have been uncovered. In this review, we will present how this knowledge was gained by studying different microorganisms. We intend to discuss how the cell, via autophagy, tries to repel these attacks with the objective of destroying the intruder, but also how some pathogens have developed strategies to subvert this. These two fates can be compared with a Tango, a dance originated in Buenos Aires, Argentina, in which the partner dancers are in close connection. One of them is the leader, embracing and involving the partner, but the follower may respond escaping from the leader. This joint dance is indeed highly synchronized and controlled, perfectly reflecting the interaction between autophagy and microorganism.


Assuntos
Dança , Imunidade Inata , Autofagia
13.
Clin Transl Sci ; 17(2): e13736, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38362837

RESUMO

SAR439459, a 'second-generation' human anti-transforming growth factor-beta (TGFß) monoclonal antibody, inhibits all TGFß isoforms and improves the antitumor activity of anti-programmed cell death protein-1 therapeutics. This study reports the pharmacodynamics (PD) and biomarker results from phase I/Ib first-in-human study of SAR439459 ± cemiplimab in patients with advanced solid tumors (NCT03192345). In dose-escalation phase (Part 1), SAR439459 was administered intravenously at increasing doses either every 2 weeks (Q2W) or every 3 weeks (Q3W) with cemiplimab IV at 3 mg/kg Q2W or 350 mg Q3W, respectively, in patients with advanced solid tumors. In dose-expansion phase (Part 2), patients with melanoma received SAR439459 IV Q3W at preliminary recommended phase II dose (pRP2D) of 22.5/7.5 mg/kg or at 22.5 mg/kg with cemiplimab 350 mg IV Q3W. Tumor biopsy and peripheral blood samples were collected for exploratory biomarker analyses to assess target engagement and PD, and results were correlated with patients' clinical parameters. SAR439459 ± cemiplimab showed decreased plasma and tissue TGFß, downregulation of TGFß-pathway activation signature, modulation of peripheral natural killer (NK) and T cell expansion, proliferation, and increased secretion of CXCL10. Conversion of tumor tissue samples from 'immune-excluded' to 'immune-infiltrated' phenotype in a representative patient with melanoma SAR439459 22.5 mg/kg with cemiplimab was observed. In paired tumor and plasma, active and total TGFß1 was more consistently elevated followed by TGFß2, whereas TGFß3 was only measurable (lower limit of quantitation ≥2.68 pg/mg) in tumors. SAR439459 ± cemiplimab showed expected peripheral PD effects and TGFß alteration. However, further studies are needed to identify biomarkers of response.


Assuntos
Anticorpos Monoclonais Humanizados , Antineoplásicos , Melanoma , Humanos , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Biomarcadores , Melanoma/tratamento farmacológico , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fatores de Crescimento Transformadores/uso terapêutico
14.
Autophagy Rep ; 2(1)2023.
Artigo em Inglês | MEDLINE | ID: mdl-37064813

RESUMO

Pathogenic protists are a group of organisms responsible for causing a variety of human diseases including malaria, sleeping sickness, Chagas disease, leishmaniasis, and toxoplasmosis, among others. These diseases, which affect more than one billion people globally, mainly the poorest populations, are characterized by severe chronic stages and the lack of effective antiparasitic treatment. Parasitic protists display complex life-cycles and go through different cellular transformations in order to adapt to the different hosts they live in. Autophagy, a highly conserved cellular degradation process, has emerged as a key mechanism required for these differentiation processes, as well as other functions that are crucial to parasite fitness. In contrast to yeasts and mammals, protist autophagy is characterized by a modest number of conserved autophagy-related proteins (ATGs) that, even though, can drive the autophagosome formation and degradation. In addition, during their intracellular cycle, the interaction of these pathogens with the host autophagy system plays a crucial role resulting in a beneficial or harmful effect that is important for the outcome of the infection. In this review, we summarize the current state of knowledge on autophagy and other related mechanisms in pathogenic protists and their hosts. We sought to emphasize when, how, and why this process takes place, and the effects it may have on the parasitic cycle. A better understanding of the significance of autophagy for the protist life-cycle will potentially be helpful to design novel anti-parasitic strategies.

15.
JCO Precis Oncol ; 7: e2200583, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36862966

RESUMO

PURPOSE: High-risk clonal hematopoiesis (CH) is frequently incidentally found in patients with solid tumors undergoing plasma cell-free DNA sequencing. Here, we aimed to determine if the incidental detection of high-risk CH by liquid biopsy may reveal occult hematologic malignancies in patients with solid tumors. MATERIALS AND METHODS: Adult patients with advanced solid cancers enrolled in the Gustave Roussy Cancer Profiling study (ClinicalTrials.gov identifier: NCT04932525) underwent at least one liquid biopsy (FoundationOne Liquid CDx). Molecular reports were discussed within the Gustave Roussy Molecular Tumor Board (MTB). Potential CH alterations were observed, and patients referred to hematology consultation in the case of pathogenic mutations in JAK2, MPL, or MYD88, irrespective of the variant allele frequency (VAF), or in DNMT3A, TET2, ASXL1, IDH1, IDH2, SF3B1, or U2AF1 with VAF ≥ 10%, while also considering patient cancer-related prognosis. TP53 mutations were discussed case-by-case. RESULTS: Between March and October 2021, 1,416 patients were included. One hundred ten patients (7.7%) carried at least one high-risk CH mutation: DNMT3A (n = 32), JAK2 (n = 28), TET2 (n = 19), ASXL1 (n = 18), SF3B1 (n = 5), IDH1 (n = 4), IDH2 (n = 3), MPL (n = 3), and U2AF1 (n = 2). The MTB advised for hematologic consultation in 45 patients. Overall, 9 patients of 18 actually addressed had confirmed hematologic malignancies that were occult in six patients: two patients had myelodysplastic syndrome, two essential thrombocythemia, one a marginal lymphoma, and one a Waldenström macroglobulinemia. The other three patients were already followed up in hematology. CONCLUSION: The incidental findings of high-risk CH through liquid biopsy may trigger diagnostic hematologic tests and reveal an occult hematologic malignancy. Patients should have a multidisciplinary case-by-case evaluation.


Assuntos
DNA Tumoral Circulante , Neoplasias Hematológicas , Hematologia , Neoplasias Primárias Desconhecidas , Adulto , Humanos , DNA Tumoral Circulante/genética , Fator de Processamento U2AF , Neoplasias Hematológicas/genética , Fatores de Transcrição , Biópsia Líquida
16.
IUBMB Life ; 64(5): 387-96, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22454195

RESUMO

The protozoan parasite Trypanosoma cruzi has a complex biological cycle that involves vertebrate and invertebrate hosts. In mammals, the infective trypomastigote form of this parasite can invade several cell types by exploiting phagocytic-like or nonphagocytic mechanisms depending on the class of cell involved. Morphological studies showed that when trypomastigotes contact macrophages, they induce the formation of plasma membrane protrusions that differ from the canonical phagocytosis that occurs in the case of noninfective epimastigotes. In contrast, when trypomastigotes infect epithelial or muscle cells, the cell surface is minimally modified, suggesting the induction of a different class of process. Lysosomal-dependent or -independent T. cruzi invasion of host cells are two different models that describe the molecular and cellular events activated during parasite entry into nonphagocytic cells. In this context, we have previously shown that induction of autophagy in host cells before infection favors T. cruzi invasion. Furthermore, we demonstrate that autophagosomes and the autophagosomal protein LC3 are recruited to the T. cruzi entry sites and that the newly formed T. cruzi parasitophorous vacuole has characteristics of an autophagolysosome. This review summarizes the current knowledge of the molecular and cellular mechanisms of T. cruzi invasion in nonphagocytic cells. Based on our findings, we propose a new model in which T. cruzi takes advantage of the upregulation of autophagy during starvation to increase its successful colonization of host cells.


Assuntos
Doença de Chagas/parasitologia , Interações Hospedeiro-Parasita , Trypanosoma cruzi/fisiologia , Animais , Autofagia , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/fisiologia , Humanos , Lisossomos/parasitologia , Modelos Biológicos , Fagocitose , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/fisiologia
17.
Front Cell Infect Microbiol ; 12: 919096, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36004334

RESUMO

Chagas disease, caused by the parasite Trypanosoma cruzi, is an infectious illness endemic to Latin America and still lacks an effective treatment for the chronic stage. In a previous study in our laboratory, we established the protective role of host autophagy in vivo during T. cruzi infection in mice and proposed this process as one of the mechanisms involved in the innate immune response against this parasite. In the search for an autophagy inducer that increases the anti-T. cruzi response in the host, we found ursolic acid (UA), a natural pentacyclic triterpene with many biological actions including autophagy induction. The aim of this work was to study the effect of UA on T. cruzi infection in vitro in the late infection stage, when the nests of intracellular parasites are forming, in both macrophages and cardiac cells. To test this effect, the cells were infected with T. cruzi for 24 h and then treated with UA (5-10 µM). The data showed that UA significantly decreased the number of amastigotes found in infected cells in comparison with non-treated cells. UA also induced the autophagy response in both macrophages and cardiac cells under the studied conditions, and the inhibition of this pathway during UA treatment restored the level of infection. Interestingly, LC3 protein, the main marker of autophagy, was recruited around amastigotes and the acidic probe LysoTracker localized with them, two key features of xenophagy. A direct cytotoxic effect of UA was also found on trypomastigotes of T. cruzi, whereas epimastigotes and amastigotes displayed more resistance to this drug at the studied concentrations. Taken together, these data showed that this natural compound reduces T. cruzi infection in the later stages by promoting parasite damage through the induction of autophagy. This action, in addition to the effect of this compound on trypomastigotes, points to UA as an interesting lead for Chagas disease treatment in the future.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Animais , Autofagia , Macrófagos/metabolismo , Camundongos , Triterpenos , Trypanosoma cruzi/metabolismo , Ácido Ursólico
18.
Curr Res Microb Sci ; 3: 100152, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909611

RESUMO

Trypanosoma cruzi, the etiologic agent of Chagas disease (CD) presents a wide genetic and phenotypic diversity that is classified into seven lineages or discrete typing units (DTU: TcI to TcVI and Tcbat). Although isolates and strains that belong to a particular group can share some attributes, such as geographic distribution, others like growth rate, cell tropism, and response to treatment can be highly variable. In addition, studies that test new trypanocidal drugs are frequently conducted on T. cruzi strains maintained for a long time in axenic culture, resulting in changes in parasite virulence and other important features. This work aimed to isolate and characterize a new T. cruzi strain from a chronic Chagas disease patient. The behavior of this isolate was studied by using standard in vitro assays and in vivo mice infection tests and compared with the T. cruzi Y strain (TcY), broadly used in research laboratories worldwide. Data showed that TcM behaves as a slow-growing strain in vitro that develops chronic infections in mice and displays high tropism to muscular tissues, in accordance with its clinical performance. In contrast, the Y strain behaved as an acute strain that can infect different types of cells and tissues. Interestingly, TcM, which belongs to DTU TcV, is more susceptible to benznidazole than TcY, a TcII strain considered moderately resistant to this drug. These differential properties contribute to the characterization of a TcV strain, one of the main lineages in the southern countries of South America, and open the possibility to introduce changes that improve the management of Chagas patients in the future.

19.
Cancers (Basel) ; 14(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36291861

RESUMO

Immunotherapy with immune checkpoint blockers (ICB) represents a valid therapeutic option in older patients for several solid cancer types. However, most of the data concerning efficacy and adverse events of ICB available are derived from younger and fitter patients. Reliable biomarkers are needed to better select the population that will benefit from ICB especially in older patients who may be at a higher risk of developing immune-related adverse events (irAEs) with a greater impact on their quality of life. The Lung Immune Prognostic Index (LIPI) is a score that combines pretreatment dNLR (neutrophils/[leukocytes − neutrophils]) and lactate dehydrogenase (LDH) and is correlated with outcomes in patients treated with ICB in non-small-cell lung cancer. We aimed to assess the impact of LIPI in ICB outcomes in a dedicated cohort of older patients. The primary objective was to study the prognostic role of LIPI score in patients aged 70 years or above in a real-life population treated with anti-programmed death-(ligand)1 (anti PD-(L)1). dNLR and LDH were collected in a prospective cohort of patients aged 70 years or above treated with PD-(L)1 inhibitors with metastatic disease between June 2014 and October 2017 at Gustave Roussy. LIPI categorizes the population into three different prognostic groups: good (dNLR ≤ 3 and LDH ≤ ULN­upper normal limit), intermediate (dNLR > 3 or LDH > ULN), and poor (dNLR > 3 and LDH > ULN). Anti PD-(L)1 benefit was analyzed according to overall survival (OS), progression free survival (PFS), and overall response rate (ORR) using RECIST v1.1. criteria. In the 191 older patients treated, most of them (95%) were ICB-naïve, and 160 (84%) had an ECOG performance status of 0−1 with a median age at ICB treatment of 77 (range, 70−93). The most common tumor types were melanoma (66%) and non-small-cell lung cancer (15%). The median follow-up duration was 18.8 months (95% CI 14.7−24.2). LIPI classified the population into three different groups: 38 (23%) patients had a good LIPI score, 84 (51%) had an intermediate LIPI score, and 43 (26%) had a poor LIPI score. The median OS was 20.7 months [95% CI, 12.6−not reached] compared to 11.2 months [95% CI, 8.41−22.2] and 4.7 months [95% CI, 2.2−11.3] in patients with a good, intermediate, and poor LIPI score, respectively (p = 0.0003). The median PFS was 9.2 months [95% CI, 6.2−18.1] in the good LIPI group, 7.2 months [95% CI, 5.4−13] in the intermediate LIPI group, and 3.9 months [95% CI, 2.3−8.2] in the poor LIPI group (p = 0.09). The rate of early death (OS < 3 months) was 37% in the poor LIPI group compared to 5% in the good LIPI group (<0.001). Poor LIPI score was associated with a poorer outcome in older patients treated with anti PD-(L)1. LIPI is a simple and accessible worldwide tool that can serve as a prognostic factor and can be useful for stratification benefit from ICB.

20.
Artigo em Inglês | MEDLINE | ID: mdl-36041820

RESUMO

OBJECTIVE: Phase I clinical trials usually include patients with advanced disease who have failed standard therapies and should benefit from early palliative care. We try to assess whether PALLIA 10, a score developed in France to help identify patients who might benefit from a palliative care referral, could be used in a phase I department trial. METHODS: We assessed PALLIA 10 score and other prognostic factors in patients enrolled in phase I trials at Gustave Roussy Cancer Center prospectively during two periods of time (cohort 1 (C1) and 2 (C2)). A double-blind assessment of the PALLIA 10 score was done in C2 by a palliative care specialist and a nurse. RESULTS: From 1 July 2018 to 1 November 2018 (C1) and from 1 December 2020 to 16 April 2021 (C2), 86 patients were assessed in C1 and 302 in C2. Median PALLIA 10 was very low in both cohorts (median 1, range 1-5 in C1 and 1-8 in C2). On C1 and C2, 12% and 5% of patients had a dedicated palliative consultation. In C2, assessment of PALLIA 10 score was significantly different between palliative care physician (median 5, range 3-8), phase I physician (median 1, range 1-6) and phase I nurse (median 3, range 1-8) (p<0.001). CONCLUSION: Median PALLIA 10 score was low when assessed by the phase I physician, which suggests the need for a better tool and appropriate clinician's education to implement early palliative care in clinical practice and trials.

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