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1.
BMC Cancer ; 23(Suppl 1): 1254, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054467

RESUMO

BACKGROUND: Advanced head and neck squamous cell carcinoma (HNSCC) has a poor prognosis, and new treatment options are needed. Combining immunotherapies with differing mechanisms of action may enhance clinical benefits compared with single-agent immunotherapy. Epacadostat, an indoleamine 2,3 dioxygenase 1 inhibitor, plus pembrolizumab, a PD-1 inhibitor, showed promising activity in advanced HNSCC in the phase 1/2 KEYNOTE-037/ECHO-202 trial. METHODS: KEYNOTE-669/ECHO-304 is a randomized, open-label, phase 3 study evaluating the efficacy and safety of pembrolizumab plus epacadostat, pembrolizumab monotherapy, and the EXTREME regimen (cetuximab with a platinum [carboplatin or cisplatin] and 5-fluorouracil) in recurrent/metastatic (R/M) HNSCC. Participants had no prior systemic therapy for R/M HNSCC and were randomly assigned (2:1:2) to pembrolizumab 200 mg intravenously every 3 weeks plus epacadostat 100 mg orally twice daily, pembrolizumab monotherapy, or EXTREME. The primary endpoint was objective response rate (ORR; investigator assessment). Secondary endpoints were safety and tolerability. Change in serum kynurenine was an exploratory endpoint. Study enrollment was discontinued early as a strategic decision on May 2, 2018, and response assessment was discontinued after first on-study imaging assessment at week 9. Data cut-off was January 17, 2019. RESULTS: Between December 1, 2017, and May 2, 2018, 89 patients were randomly allocated to pembrolizumab plus epacadostat (n = 35), pembrolizumab monotherapy (n = 19), or EXTREME (n = 35). ORR (95% CI) was 31% (17%-49%) for pembrolizumab plus epacadostat, 21% (6%-46%) for pembrolizumab monotherapy, and 34% (19%-52%) for EXTREME. Treatment-related adverse events (TRAEs) occurred in 82% (n = 28) of patients receiving pembrolizumab plus epacadostat, 63% (n = 12) receiving pembrolizumab monotherapy, and 100% (n = 34) receiving EXTREME. Grade 3-4 TRAEs occurred in 24% (n = 8) of patients receiving pembrolizumab plus epacadostat, 16% (n = 3) receiving pembrolizumab monotherapy, and 82% (n = 28) receiving EXTREME. No deaths occurred due to AEs. Pembrolizumab plus epacadostat treatment reduced kynurenine levels but not to that of healthy subjects. CONCLUSIONS: Pembrolizumab plus epacadostat and pembrolizumab monotherapy provided a similar response rate to EXTREME and demonstrated a manageable safety profile in patients with R/M HNSCC. TRIAL REGISTRATION: NCT03358472. Date of trial registration: November 30, 2017.


Assuntos
Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Masculino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Idoso , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Adulto , Sulfonamidas/uso terapêutico , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Oximas
5.
J Endocrinol Invest ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451399

RESUMO

PURPOSE: Peritoneal metastases (PM) of neuroendocrine neoplasm (NEN) origin are identified with increasing frequency and exert a significant effect on quality of life and clinical status of the patients. The aim of this study was to identify the characteristics and the prognostic significance of PM in patients with NENs. METHODS: A retrospective analysis of the data of patients from two tertiary referral centers was performed. We defined a control group of age- and gender-matched NEN patients with comparable stage IV disease but no PM. RESULTS: We analysed 70 patients (41 females) with PM. Small intestine was the most common primary NEN site (87.1%). PM prevalence was 10.3%. Forty-four patients presented with synchronous PM, whereas 26 developed metachronous PM. The majority of patients had other concomitant metastases (50 hepatic, 6 lung and 12 bone metastases). Twelve patients developed intestinal obstruction. After PM diagnosis, 76% of patients received treatment with somatostatin analogues while six patients (8.6%) were treated with peptide receptor radionuclide therapy (PRRT). The median progression-free survival (PFS) in the PRRT-treated group was 15 months (95% CI 2-28). Median overall survival (OS) in the PM group was 142 months [95% CI 71-213] while it was not reached in the control group. CONCLUSION: Peritoneal metastases show low prevalence among NEN patients and are most likely to develop in patients with small intestinal NENs and advanced metastatic disease. The presence of PM does seem to be associated with a negative prognostic impact on OS of NEN patients and their identification and prompt treatment is of major importance.

6.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38547398

RESUMO

The hypervirulent lineages of Klebsiella pneumoniae (HvKp) cause invasive infections such as Klebsiella-liver abscess. Invasive infection often occurs after initial colonization of the host gastrointestinal tract by HvKp. Over 80% of HvKp isolates belong to the clonal group 23 sublineage I that has acquired genomic islands (GIs) GIE492 and ICEKp10. Our analysis of 12 361 K. pneumoniae genomes revealed that GIs GIE492 and ICEKp10 are co-associated with the CG23-I and CG10118 HvKp lineages. GIE492 and ICEKp10 enable HvKp to make a functional bacteriocin microcin E492 (mccE492) and the genotoxin colibactin, respectively. We discovered that GIE492 and ICEKp10 play cooperative roles and enhance gastrointestinal colonization by HvKp. Colibactin is the primary driver of this effect, modifying gut microbiome diversity. Our in vitro assays demonstrate that colibactin and mccE492 kill or inhibit a range of Gram-negative Klebsiella species and Escherichia coli strains, including Gram-positive bacteria, sometimes cooperatively. Moreover, mccE492 and colibactin kill human anaerobic gut commensals that are similar to the taxa found altered by colibactin in the mouse intestines. Our findings suggest that GIs GIE492 and ICEKp10 enable HvKp to kill several commensal bacterial taxa during interspecies interactions in the gut. Thus, acquisition of GIE492 and ICEKp10 could enable better carriage in host populations and explain the dominance of the CG23-I HvKp lineage.


Assuntos
Ilhas Genômicas , Klebsiella pneumoniae , Peptídeos , Policetídeos , Animais , Camundongos , Humanos , Virulência , Klebsiella pneumoniae/genética , Fatores de Virulência/genética , Antibacterianos/farmacologia
7.
Invest New Drugs ; 42(1): 145-159, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38324085

RESUMO

C-X-C motif chemokine receptor 2 (CXCR2) has a role in tumor progression, lineage plasticity, and reduction of immune checkpoint inhibitor efficacy. Preclinical evidence suggests potential benefit of CXCR2 inhibition in multiple solid tumors. In this phase 2 study (NCT03473925), adults with previously treated advanced or metastatic castration-resistant prostate cancer (CRPC), microsatellite-stable colorectal cancer (MSS CRC), or non-small-cell lung cancer (NSCLC) were randomized 1:1 to the CXCR2 antagonist navarixin 30 or 100 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks up to 35 cycles. Primary endpoints were investigator-assessed objective response rate (RECIST v1.1) and safety. Of 105 patients (CRPC, n=40; MSS CRC, n=40; NSCLC, n=25), 3 had a partial response (2 CRPC, 1 MSS CRC) for ORRs of 5%, 2.5%, and 0%, respectively. Median progression-free survival was 1.8-2.4 months without evidence of a dose-response relationship, and the study was closed at a prespecified interim analysis for lack of efficacy. Dose-limiting toxicities occurred in 2/48 patients (4%) receiving navarixin 30 mg and 3/48 (6%) receiving navarixin 100 mg; events included grade 4 neutropenia and grade 3 transaminase elevation, hepatitis, and pneumonitis. Treatment-related adverse events occurred in 70/105 patients (67%) and led to treatment discontinuation in 7/105 (7%). Maximal reductions from baseline in absolute neutrophil count were 44.5%-48.2% (cycle 1) and 37.5%-44.2% (cycle 2) and occurred within 6-12 hours postdose in both groups. Navarixin plus pembrolizumab did not demonstrate sufficient efficacy in this study. Safety and tolerability of the combination were manageable. (Trial registration: ClinicalTrials.gov , NCT03473925).


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neoplasias de Próstata Resistentes à Castração , Masculino , Adulto , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Anticorpos Monoclonais Humanizados/efeitos adversos , Fatores Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
8.
Cell Biosci ; 14(1): 19, 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38311785

RESUMO

BACKGROUND: The tumour microenvironment (TME) consists of tumour-supportive immune cells, endothelial cells, and fibroblasts. PhenoCycler, a high-plex single cell spatial biology imaging platform, is used to characterize the complexity of the TME. Researchers worldwide harvest and bank tissues from mouse models which are employed to model a plethora of human disease. With the explosion of interest in spatial biology, these panoplies of archival tissues provide a valuable resource to answer new questions. Here, we describe our protocols for developing tunable PhenoCycler multiplexed imaging panels and describe our open-source data analysis pipeline. Using these protocols, we used PhenoCycler to spatially resolve the TME of 8 routinely employed pre-clinical models of lymphoma, breast cancer, and melanoma preserved as FFPE. RESULTS: Our data reveal distinct TMEs in the different cancer models that were imaged and show that cell-cell contacts differ depending on the tumour type examined. For instance, we found that the immune infiltration in a murine model of melanoma is altered in cellular organization in melanomas that become resistant to αPD-1 therapy, with depletions in a number of cell-cell interactions. CONCLUSIONS: This work presents a valuable resource study seamlessly adaptable to any field of research involving murine models. The methodology described allows researchers to address newly formed hypotheses using archival materials, bypassing the new to perform new mouse studies.

9.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1559722

RESUMO

La membrana amniótica (MA), ubicada en el lado interno de la placenta fetal, ha sido objeto de múltiples investigaciones para intentar dilucidar su papel embriológico y su potencial celular terapéutico. Actualmente las limitaciones del estudio en fetos humanos hacen que parte de su funcionamiento sea una incógnita, sin embargo algunos estudios clínicos y básicos nos dan luz sobre su papel en la médica moderna. Se realizó una revisión bibliográfica de la literatura desde 1960 hasta 2022, empleando bases de datos como PubMed, SciELO y Scopus, siendo incluidos un total de 50 artículos y dos textos de embriología. El objetivo de esta revisión narrativa fue sintetizar la información sobre la angiogénesis y su importancia clínica. La información recopilada permitió evidenciar que las propiedades de curación de la piel del feto se deben a factores intrínsecos del feto, y a que las células epiteliales amnióticas humanas poseen una diferenciación similar a las células madre embrionarias, con la capacidad de diferenciación similar al de las células mesenquimales, resaltando su importancia clínica por sus características regenerativas. En conclusión, el desarrollo embrionario humano sigue siendo relativamente inexplicable, pero su conocimiento ha permitido grandes avances, que podrían ser útiles en terapias de regeneración, reparación de tejidos y órganos lesionados.


The amniotic membrane, located on the inner side of the fetal placenta, has been the subject of multiple investigations to try to elucidate its embryological role and its therapeutic cellular potential. Currently, the limitations of the study in human fetuses mean that part of its functioning is unknown, however, some clinical and basic studies shed light on its role in modern medicine. A bibliographic review of the literature was carried out from 1960 to 2022, using databases such as PubMed, SciELO and Scopus, including a total of 50 articles and two embryology texts. The objective of this narrative review was to synthesize information on angiogenesis and its clinical importance. The information collected made it possible to show that the healing properties of the fetal skin are due to intrinsic factors of the fetus, and that human amniotic epithelial cells have a differentiation similar to embryonic stem cells, with the differentiation capacity similar to that of mesenchymal cells, highlighting their clinical importance due to their regenerative characteristics. In conclusion, human embryonic development remains relatively inexplicable, but its knowledge has allowed great advances, which could be useful in regeneration therapies, repair of injured tissues and organs.

11.
Nat Med ; 30(1): 271-278, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38052910

RESUMO

KRAS G12C mutation is prevalent in ~4% of colorectal cancer (CRC) and is associated with poor prognosis. Divarasib, a KRAS G12C inhibitor, has shown modest activity as a single agent in KRAS G12C-positive CRC at 400 mg. Epidermal growth factor receptor has been recognized as a major upstream activator of RAS-MAPK signaling, a proposed key mechanism of resistance to KRAS G12C inhibition in CRC. Here, we report on divarasib plus cetuximab (epidermal growth factor receptor inhibitor) in patients with KRAS G12C-positive CRC (n = 29) from arm C of an ongoing phase 1b trial. The primary objective was to evaluate safety. Secondary objectives included preliminary antitumor activity. The safety profile of this combination was consistent with those of single-agent divarasib and cetuximab. Treatment-related adverse events led to divarasib dose reductions in four patients (13.8%); there were no treatment withdrawals. The objective response rate was 62.5% (95% confidence interval: 40.6%, 81.2%) in KRAS G12C inhibitor-naive patients (n = 24). The median duration of response was 6.9 months. The median progression-free survival was 8.1 months (95% confidence interval: 5.5, 12.3). As an exploratory objective, we observed a decline in KRAS G12C variant allele frequency associated with response and identified acquired genomic alterations at disease progression that may be associated with resistance. The manageable safety profile and encouraging antitumor activity of divarasib plus cetuximab support the further investigation of this combination in KRAS G12C-positive CRC.ClinicalTrials.gov identifier: NCT04449874.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Cetuximab/efeitos adversos , Cetuximab/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Receptores ErbB/genética , Intervalo Livre de Progressão , Mutação/genética
12.
Curr Oncol ; 30(9): 7852-7859, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37754485

RESUMO

Camu camu (CC) is a prebiotic that selectively stimulates growth and activity of beneficial gut microbiota. Work in murine models demonstrated that castalagin, the active compound in CC, preferentially binds to beneficial gut microbiome bacteria, promoting a stronger CD8+T cell anti-cancer response. We present two patients with metastatic melanoma whose cancer progressed on immune checkpoint inhibitors (ICIs) and developed clinically significant immune-related adverse events (irAEs). They were rechallenged with ICIs in combination with CC. The first patient is a 71-year-old woman with metastatic melanoma, whose ICI treatment was complicated by immune-related pneumonitis and colitis. Upon progression on maintenance nivolumab, CC was added to nivolumab, leading to a near complete response (CR). The second patient is a 90-year-old man with recurrent unresectable melanoma, treated with nivolumab, complicated by immune-related rash and diabetes. He developed new subcutaneous calf lesions and a metastatic popliteal lymph node. CC was added to nivolumab. One month later, the patient experienced a CR. Both patients have been on nivolumab and CC with durable responses for more than a year, with minimal irAEs. These two cases suggest that CC may modulate the microbiome, synergizing with ICIs to produce deep, durable responses with minimal irAEs.


Assuntos
Antineoplásicos Imunológicos , Melanoma , Masculino , Feminino , Humanos , Animais , Camundongos , Idoso , Idoso de 80 Anos ou mais , Nivolumabe/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Recidiva Local de Neoplasia , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma Maligno Cutâneo
13.
J Clin Invest ; 133(20)2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37616051

RESUMO

Melanomas reprogram their metabolism to rapidly adapt to therapy-induced stress conditions, allowing them to persist and ultimately develop resistance. We report that a subpopulation of melanoma cells tolerate MAPK pathway inhibitors (MAPKis) through a concerted metabolic reprogramming mediated by peroxisomes and UDP-glucose ceramide glycosyltransferase (UGCG). Compromising peroxisome biogenesis, by repressing PEX3 expression, potentiated the proapoptotic effects of MAPKis via an induction of ceramides, an effect limited by UGCG-mediated ceramide metabolism. Cotargeting PEX3 and UGCG selectively eliminated a subset of metabolically active, drug-tolerant CD36+ melanoma persister cells, thereby sensitizing melanoma to MAPKis and delaying resistance. Increased levels of peroxisomal genes and UGCG were found in patient-derived MAPKi-relapsed melanomas, and simultaneously inhibiting PEX3 and UGCG restored MAPKi sensitivity in multiple models of therapy resistance. Finally, combination therapy consisting of a newly identified inhibitor of the PEX3-PEX19 interaction, a UGCG inhibitor, and MAPKis demonstrated potent antitumor activity in preclinical melanoma models, thus representing a promising approach for melanoma treatment.


Assuntos
Melanoma , Peroxissomos , Humanos , Peroxissomos/metabolismo , Metabolismo dos Lipídeos , Melanoma/genética , Ceramidas/farmacologia , Ceramidas/metabolismo
14.
N Engl J Med ; 389(8): 710-721, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37611121

RESUMO

BACKGROUND: Divarasib (GDC-6036) is a covalent KRAS G12C inhibitor that was designed to have high potency and selectivity. METHODS: In a phase 1 study, we evaluated divarasib administered orally once daily (at doses ranging from 50 to 400 mg) in patients who had advanced or metastatic solid tumors that harbor a KRAS G12C mutation. The primary objective was an assessment of safety; pharmacokinetics, investigator-evaluated antitumor activity, and biomarkers of response and resistance were also assessed. RESULTS: A total of 137 patients (60 with non-small-cell lung cancer [NSCLC], 55 with colorectal cancer, and 22 with other solid tumors) received divarasib. No dose-limiting toxic effects or treatment-related deaths were reported. Treatment-related adverse events occurred in 127 patients (93%); grade 3 events occurred in 15 patients (11%) and a grade 4 event in 1 patient (1%). Treatment-related adverse events resulted in a dose reduction in 19 patients (14%) and discontinuation of treatment in 4 patients (3%). Among patients with NSCLC, a confirmed response was observed in 53.4% of patients (95% confidence interval [CI], 39.9 to 66.7), and the median progression-free survival was 13.1 months (95% CI, 8.8 to could not be estimated). Among patients with colorectal cancer, a confirmed response was observed in 29.1% of patients (95% CI, 17.6 to 42.9), and the median progression-free survival was 5.6 months (95% CI, 4.1 to 8.2). Responses were also observed in patients with other solid tumors. Serial assessment of circulating tumor DNA showed declines in KRAS G12C variant allele frequency associated with response and identified genomic alterations that may confer resistance to divarasib. CONCLUSIONS: Treatment with divarasib resulted in durable clinical responses across KRAS G12C-positive tumors, with mostly low-grade adverse events. (Funded by Genentech; ClinicalTrials.gov number, NCT04449874.).


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Colorretais , Inibidores Enzimáticos , Neoplasias Pulmonares , Humanos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Administração Oral , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/uso terapêutico
15.
Cancers (Basel) ; 15(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37568569

RESUMO

BACKGROUND: The incidence of cutaneous melanoma (CM) is increasing at an alarming rate in Canada and elsewhere around the world. Significant regional differences in CM incidence have been identified in Atlantic provinces. The goal of this study is to compare ultraviolet exposure, sun protective behaviours, level of worry and baseline CM knowledge in provinces with a high versus low incidence of CM as well, as between various demographic groups. METHODS: A cross-sectional survey study was conducted in Atlantic provinces between July 2020 and August 2022. All participants aged ≥ 16 years with a completed survey were eligible. Survey responses were summarized using frequency counts, percentages, and means. Two-sided Z-tests for equality of proportions and logistic regression models were used to compare the survey results between geographic and demographic groups. RESULTS: In total, 7861 participants were included (28.0% men; mean age 61.3 years; response rate 28%). Our results (gender- and age-adjusted odds ratio, 95% confidence interval) show that high-incidence provinces for CM (Prince Edward Island and Nova Scotia) had significantly more sunburns (OR 2.00, 1.72-2.31), total sun exposure (OR 2.05, 1.68-2.50), recreational sun exposure (OR 1.95, 1.61-2.35) and tans (OR 1.77, 1.53-2.05) than individuals in low-incidence provinces (Newfoundland and Labrador). However, individuals in high-incidence provinces displayed more protective behaviors: there were less tanning bed users (OR 0.82, 0.71-0.95), they checked their skin more frequently for new moles (OR 1.26, 1.06-1.51) and practiced more sun protection overall. Additional analyses are presented based on education, income, sexual orientation and gender. DISCUSSION: These findings suggest that future efforts aimed at reducing the CM burden in Atlantic Canada should be tailored for target geographic and/or demographic groups. LIMITATIONS: the study participants are not representative of the population in Atlantic Canada due to recruitment strategies.

16.
mBio ; 14(4): e0129723, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37530523

RESUMO

Hypervirulent Klebsiella pneumoniae causes liver abscess and potentially devastating metastatic complications. The majority of Klebsiella-induced liver abscess are caused by the CG23-I sublineage of hypervirulent Klebsiella pneumoniae. This and some other lineages possess a >200-kb virulence plasmid. We discovered a novel protein IroP nestled in the virulence plasmid-encoded salmochelin operon that cross-regulates and suppresses the promoter activity of chromosomal type 3 fimbriae (T3F) gene transcription. IroP is itself repressed by iron through the ferric uptake regulator. Iron-rich conditions increase T3F and suppress capsule mucoviscosity, leading to biofilm formation and cell adhesion. Conversely, iron-poor conditions cause a transcriptional switch to hypermucoid capsule production and T3F repression. The likely acquisition of iroP on mobile genetic elements and successful adaptive integration into the genetic circuitry of a major lineage of hypervirulent K. pneumoniae reveal a powerful example of plasmid chromosomal cross talk that confers an evolutionary advantage. Our discovery also addresses the conundrum of how the hypermucoid capsule that impedes adhesion could be regulated to facilitate biofilm formation and colonization. The acquired ability of the bacteria to alternate between a state favoring dissemination and one that favors colonization in response to iron availability through transcriptional regulation offers novel insights into the evolutionary success of this pathogen. IMPORTANCE Hypervirulent Klebsiella pneumoniae contributes to the majority of monomicrobial-induced liver abscess infections that can lead to several other metastatic complications. The large virulence plasmid is highly stable in major lineages, suggesting that it provides survival benefits. We discovered a protein IroP encoded on the virulence plasmid that suppresses expression of the type 3 fimbriae. IroP itself is regulated by iron, and we showed that iron regulates hypermucoid capsule production while inversely regulating type 3 fimbriae expression through IroP. The acquisition and integration of this inverse transcriptional switch between fimbriae and capsule mucoviscosity shows an evolved sophisticated plasmid-chromosomal cross talk that changes the behavior of hypervirulent K. pneumoniae in response to a key nutrient that could contribute to the evolutionary success of this pathogen.

17.
Nat Med ; 29(8): 2121-2132, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37414899

RESUMO

Fecal microbiota transplantation (FMT) represents a potential strategy to overcome resistance to immune checkpoint inhibitors in patients with refractory melanoma; however, the role of FMT in first-line treatment settings has not been evaluated. We conducted a multicenter phase I trial combining healthy donor FMT with the PD-1 inhibitors nivolumab or pembrolizumab in 20 previously untreated patients with advanced melanoma. The primary end point was safety. No grade 3 adverse events were reported from FMT alone. Five patients (25%) experienced grade 3 immune-related adverse events from combination therapy. Key secondary end points were objective response rate, changes in gut microbiome composition and systemic immune and metabolomics analyses. The objective response rate was 65% (13 of 20), including four (20%) complete responses. Longitudinal microbiome profiling revealed that all patients engrafted strains from their respective donors; however, the acquired similarity between donor and patient microbiomes only increased over time in responders. Responders experienced an enrichment of immunogenic and a loss of deleterious bacteria following FMT. Avatar mouse models confirmed the role of healthy donor feces in increasing anti-PD-1 efficacy. Our results show that FMT from healthy donors is safe in the first-line setting and warrants further investigation in combination with immune checkpoint inhibitors. ClinicalTrials.gov identifier NCT03772899 .


Assuntos
Transplante de Microbiota Fecal , Melanoma , Animais , Camundongos , Transplante de Microbiota Fecal/métodos , Inibidores de Checkpoint Imunológico , Fezes/microbiologia , Melanoma/terapia , Imunoterapia , Resultado do Tratamento
18.
Mol Cancer Ther ; 22(2): 192-204, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36722142

RESUMO

Aberrant cell-cycle progression is characteristic of melanoma, and CDK4/6 inhibitors, such as palbociclib, are currently being tested for efficacy in this disease. Despite the promising nature of CDK4/6 inhibitors, their use as single agents in melanoma has shown limited clinical benefit. Herein, we discovered that treatment of tumor cells with palbociclib induces the phosphorylation of the mRNA translation initiation factor eIF4E. When phosphorylated, eIF4E specifically engenders the translation of mRNAs that code for proteins involved in cell survival. We hypothesized that cancer cells treated with palbociclib use upregulated phosphorylated eIF4E (phospho-eIF4E) to escape the antitumor benefits of this drug. Indeed, we found that pharmacologic or genetic disruption of MNK1/2 activity, the only known kinases for eIF4E, enhanced the ability of palbociclib to decrease clonogenic outgrowth. Moreover, a quantitative proteomics analysis of melanoma cells treated with combined MNK1/2 and CDK4/6 inhibitors showed downregulation of proteins with critical roles in cell-cycle progression and mitosis, including AURKB, TPX2, and survivin. We also observed that palbociclib-resistant breast cancer cells have higher basal levels of phospho-eIF4E, and that treatment with MNK1/2 inhibitors sensitized these palbociclib-resistant cells to CDK4/6 inhibition. In vivo we demonstrate that the combination of MNK1/2 and CDK4/6 inhibition significantly increases the overall survival of mice compared with either monotherapy. Overall, our data support MNK1/2 inhibitors as promising drugs to potentiate the antineoplastic effects of palbociclib and overcome therapy-resistant disease.


Assuntos
Neoplasias da Mama , Melanoma , Inibidores de Proteínas Quinases , Animais , Camundongos , Fator de Iniciação 4E em Eucariotos , Melanoma/tratamento farmacológico , Piperazinas/farmacologia , Piridinas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Antineoplásicos/farmacologia
19.
Elife ; 122023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36718985

RESUMO

Background: The COVID-19 pandemic has disrupted cancer care, raising concerns regarding the impact of wait time, or 'lag time', on clinical outcomes. We aimed to contextualize pandemic-related lag times by mapping pre-pandemic evidence from systematic reviews and/or meta-analyses on the association between lag time to cancer diagnosis and treatment with mortality- and morbidity-related outcomes. Methods: We systematically searched MEDLINE, EMBASE, Web of Science, and Cochrane Library of Systematic Reviews for reviews published prior to the pandemic (1 January 2010-31 December 2019). We extracted data on methodological characteristics, lag time interval start and endpoints, qualitative findings from systematic reviews, and pooled risk estimates of mortality- (i.e., overall survival) and morbidity- (i.e., local regional control) related outcomes from meta-analyses. We categorized lag times according to milestones across the cancer care continuum and summarized outcomes by cancer site and lag time interval. Results: We identified 9032 records through database searches, of which 29 were eligible. We classified 33 unique types of lag time intervals across 10 cancer sites, of which breast, colorectal, head and neck, and ovarian cancers were investigated most. Two systematic reviews investigating lag time to diagnosis reported different findings regarding survival outcomes among paediatric patients with Ewing's sarcomas or central nervous system tumours. Comparable risk estimates of mortality were found for lag time intervals from surgery to adjuvant chemotherapy for breast, colorectal, and ovarian cancers. Risk estimates of pathologic complete response indicated an optimal time window of 7-8 weeks for neoadjuvant chemotherapy completion prior to surgery for rectal cancers. In comparing methods across meta-analyses on the same cancer sites, lag times, and outcomes, we identified critical variations in lag time research design. Conclusions: Our review highlighted measured associations between lag time and cancer-related outcomes and identified the need for a standardized methodological approach in areas such as lag time definitions and accounting for the waiting-time paradox. Prioritization of lag time research is integral for revised cancer care guidelines under pandemic contingency and assessing the pandemic's long-term effect on patients with cancer. Funding: The present work was supported by the Canadian Institutes of Health Research (CIHR-COVID-19 Rapid Research Funding opportunity, VR5-172666 grant to Eduardo L. Franco). Parker Tope, Eliya Farah, and Rami Ali each received an MSc. stipend from the Gerald Bronfman Department of Oncology, McGill University.


Assuntos
COVID-19 , Neoplasias Colorretais , Neoplasias Ovarianas , Humanos , Criança , Feminino , COVID-19/diagnóstico , COVID-19/terapia , Pandemias , Canadá , Revisões Sistemáticas como Assunto , Teste para COVID-19
20.
J Immunother Cancer ; 10(11)2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36328377

RESUMO

BACKGROUND: The role and sequencing of combination immuno-oncology (IO) therapy following progression on or after first-line IO therapy has not been well-established. The Fast Real-time Assessment of Combination Therapies in Immuno-ONcology (FRACTION) program is an open-label, phase 2 platform trial designed to evaluate multiple IO combinations in patients with advanced renal cell carcinoma (aRCC) who progressed during or after prior IO therapy. Here, we describe the results for patients treated with nivolumab plus ipilimumab. For enrollment in track 2 (reported here), patients with histologically confirmed clear cell aRCC, Karnofsky performance status ≥70%, and life expectancy ≥3 months who had previously progressed after IO (anti-programmed death 1 (PD-1), anti-programmed death-ligand 1 (PD-L1), or anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4)) therapy were eligible. Previous treatment with anti-CTLA-4 therapy plus anti-PD-1/PD-L1 therapy precluded eligibility for enrollment in the nivolumab plus ipilimumab arm. Patients were treated with nivolumab 3 mg/kg plus ipilimumab 1 mg/kg every 3 weeks for four doses, followed by nivolumab 480 mg every 4 weeks for up to 2 years or until progression, toxicity, or protocol-specified discontinuation. The primary outcome measures were objective response rate (ORR), duration of response (DOR), and progression-free survival (PFS) rate at 24 weeks. Secondary outcomes were safety and tolerability up to 2 years. Overall survival (OS) was a tertiary/exploratory endpoint. Overall, 46 patients were included with a median follow-up of 33.8 months. The ORR was 17.4% (95% CI, 7.8 to 31.4) with eight (17.4%) patients achieving partial response. Stable disease was achieved in 19 (41.3%) patients, while 14 (30.4%) had progressive disease. Median DOR (range) was 16.4 (2.1+ to 27.0+) months. The PFS rate at 24 weeks was 43.2%, and median OS was 23.8 (95% CI, 13.2 to not reached) months. Grade 3-4 immune-mediated adverse events were reported in seven (15.2%) patients. No treatment-related deaths were reported. Patients with aRCC treated with nivolumab plus ipilimumab may derive durable clinical benefit after progression on previous IO therapies, including heavily pretreated patients, with a manageable safety profile that was consistent with previously published safety outcomes. These outcomes contribute to the knowledge of optimal sequencing of IO therapies for patients with aRCC with high unmet needs. TRIAL REGISTRATION NUMBER: NCT02996110.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Antígeno B7-H1/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Ipilimumab/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Nivolumabe/uso terapêutico , Imunoterapia , Resultado do Tratamento
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