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1.
Cancers (Basel) ; 16(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38791882

RESUMO

Results from the phase III Keynote-024 clinical trial established pembrolizumab monotherapy as the first-line standard of care for patients with metastatic NSCLC who have PD-L1 expression ≥ 50%, EGFR, and ALK wild-type tumors. However, given the differences between patients treated in routine clinical practice and those treated in a clinical trial, real-world data are needed to confirm the treatment benefit in standard practice. Given the lack of data on large cohorts of patients with long follow-ups, we designed an observational retrospective study of patients with metastatic NSCLC who were treated with pembrolizumab, starting from its reimbursement eligibility until December 2020. The primary endpoints were PFS and OS, determined using the Kaplan-Meier method. Response and safety were also evaluated. We followed 880 patients (median follow-up: 35.1 months) until February 2022. Median PFS and OS were 8.6 months (95% CI: 7.6-10.0) and 25.5 months (95% CI: 21.8-31.6), respectively. We also found that ECOG PS, PD-L1 expression, and habitual smoking were prognostic factors for PFS, while age, sex, ECOG PS, habitual smoking and histology had an impact on OS. Multivariable analysis confirms the prognostic role of PD-L1 for PFS and of ECOG for both PFS and OS. 39.9% of patients reported an adverse event, but only 6.3% of patients discontinued therapy due to toxicity. Our results suggest a long-term benefit of pembrolizumab in the first-line setting, as well as a safety profile consistent with the results of Keynote-024. Many collected variables appear to influence clinical outcome, but results from these exploratory unadjusted analyses should be interpreted with caution.

2.
Int J Mol Sci ; 25(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38612864

RESUMO

Flavonoids exhibit various bioactivities including anti-oxidant, anti-tumor, anti-inflammatory, and anti-viral properties. Methylated flavonoids are particularly significant due to their enhanced oral bioavailability, improved intestinal absorption, and greater stability. The heterologous production of plant flavonoids in bacterial factories involves the need for enough biosynthetic precursors to allow for high production levels. These biosynthetic precursors are malonyl-CoA and l-tyrosine. In this work, to enhance flavonoid biosynthesis in Streptomyces albidoflavus, we conducted a transcriptomics study for the identification of candidate genes involved in l-tyrosine catabolism. The hypothesis was that the bacterial metabolic machinery would detect an excess of this amino acid if supplemented with the conventional culture medium and would activate the genes involved in its catabolism towards energy production. Then, by inactivating those overexpressed genes (under an excess of l-tyrosine), it would be possible to increase the intracellular pools of this precursor amino acid and eventually the final flavonoid titers in this bacterial factory. The RNAseq data analysis in the S. albidoflavus wild-type strain highlighted the hppD gene encoding 4-hydroxyphenylpyruvate dioxygenase as a promising target for knock-out, exhibiting a 23.2-fold change (FC) in expression upon l-tyrosine supplementation in comparison to control cultivation conditions. The subsequent knock-out of the hppD gene in S. albidoflavus resulted in a 1.66-fold increase in the naringenin titer, indicating enhanced flavonoid biosynthesis. Leveraging the improved strain of S. albidoflavus, we successfully synthesized the methylated flavanones hesperetin, homoeriodictyol, and homohesperetin, achieving titers of 2.52 mg/L, 1.34 mg/L, and 0.43 mg/L, respectively. In addition, the dimethoxy flavanone homohesperetin was produced as a byproduct of the endogenous metabolism of S. albidoflavus. To our knowledge, this is the first time that hppD deletion was utilized as a strategy to augment the biosynthesis of flavonoids. Furthermore, this is the first report where hesperetin and homoeriodictyol have been synthesized from l-tyrosine as a precursor. Therefore, transcriptomics is, in this case, a successful approach for the identification of catabolism reactions affecting key precursors during flavonoid biosynthesis, allowing the generation of enhanced production strains.


Assuntos
Anormalidades Craniofaciais , Flavonas , Flavonoides , Perfilação da Expressão Gênica , Hesperidina , Streptomyces , Aminoácidos , Tirosina
3.
Front Oncol ; 11: 686308, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34820323

RESUMO

BACKGROUND: Cutaneous squamous cell carcinoma (CSCC) is the second most common skin cancer whose incidence is growing parallel to the lengthening of the average lifespan. Cemiplimab, an antiPD-1 monoclonal antibody, is the first approved immunotherapy for patients with locally advanced CSCC (laCSCC) or metastatic CSCC (mCSCC) thanks to phase I and II studies showing high antitumor activity and good tolerability. Nevertheless, at present, very few data are available regarding cemiplimab in real-life experience and in frail, elderly, and immunosuppressed patients as well as regarding biomarkers able to predict response so as to guide therapeutic choices. PATIENTS AND METHODS: We built a retroprospective cohort study including 30 non-selected patients with laCSCC (25) and mCSCC (five) treated with cemiplimab from August 2019 to November 2020. Clinical outcomes, toxicity profile, and correlations with disease, patients, and peripheral blood parameters are explored. RESULTS: The median age was 81 years (range, 36-95), with 24 males and five patients having an immunosuppressive condition, while the frailty prevalence was 83% based on index derived from age, Eastern Cooperative Oncology Group performance status, and Charlson Comorbidity Index. We reported 23 responses (76.7%) with nine complete responses (30%). A statistically significant higher response rate was observed in head and neck primary tumors and in patients with hemoglobin level >12 g/dl. No difference was observed with respect to frailty, median age, sex, and body mass index. The baseline low neuthophil/lymphocyte ratio and low platelet/lymphocyte ratio resulted to be also correlated with a better response. Moreover, lymphocyte, neutrophil, and monocyte behaviors had an opposite trend in responders and non-responders. An overall response was reported in four of five immunosuppressed patients. Seventeen patients (57.6%) have an ongoing response and are still alive. Six responders had interrupted treatment (two for toxicity and four for personal choice) but maintained their response. The treatment was well tolerated by the majority of patients. The most common adverse events were fatigue in seven patients (23.3%) and skin toxicity in 10 patients (33.3%), including pruritus in six patients, rash in three patients, and bullous erythema in one patient. CONCLUSIONS: In our real-life experience, cemiplimab showed a high antitumor activity with acceptable safety profile similar to those in trials with selected patients. Moreover, its antitumor activity resulted to be not impaired in very elderly patients and in those with immunocompromised status.

4.
Int J Mol Sci ; 22(4)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671327

RESUMO

Peripheral neurologic complications are frequent adverse events during oncologic treatments and often lead to dose reduction, administration delays with time elongation of the therapeutic plan and, not least, worsening of patients' quality of life. Experience skills are required to recognize symptoms and clinical evidences and the collaboration between different health professionals, in particular oncologists and hospital pharmacists, grants a correct management of this undesirable occurrence. Some classes of drugs (platinates, vinca alkaloids, taxanes) typically develop this kind of side effect, but the genesis of chemotherapy-induced peripheral neuropathy is not linked to a single mechanism. This paper aims from one side at summarizing and explaining all the scattering mechanisms of chemotherapy-induced peripheral neuropathy through a detailed literature revision, on the other side at finding new approaches to possible treatments, in order to facilitate the collaboration between oncologists, hematologists and hospital pharmacists.


Assuntos
Antineoplásicos/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/patologia , Humanos , Inibidores de Proteínas Quinases/efeitos adversos
5.
Appl Microbiol Biotechnol ; 105(2): 551-568, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33394149

RESUMO

Streptomyces is one of the most versatile genera for biotechnological applications, widely employed as platform in the production of drugs. Although streptomycetes have a complex life cycle and metabolism that would need multidisciplinary approaches, review papers have generally reported only studies on single aspects like the isolation of new strains and metabolites, morphology investigations, and genetic or metabolic studies. Besides, even if streptomycetes are extensively used in industry, very few review papers have focused their attention on the technical aspects of biotechnological processes of drug production and bioconversion and on the key parameters that have to be set up. This mini-review extensively illustrates the most innovative developments and progresses in biotechnological production and bioconversion processes of antibiotics, immunosuppressant, anticancer, steroidal drugs, and anthelmintic agents by streptomycetes, focusing on the process development aspects, describing the different approaches and technologies used in order to improve the production yields. The influence of nutrients and oxygen on streptomycetes metabolism, new fed-batch fermentation strategies, innovative precursor supplementation approaches, and specific bioreactor design as well as biotechnological strategies coupled with metabolic engineering and genetic tools for strain improvement is described. The use of whole, free, and immobilized cells on unusual supports was also reported for bioconversion processes of drugs. The most outstanding thirty investigations published in the last 8 years are here reported while future trends and perspectives of biotechnological research in the field have been illustrated. KEY POINTS: • Updated Streptomyces biotechnological processes for drug production are reported. • Innovative approaches for Streptomyces-based biotransformation of drugs are reviewed. • News about fermentation and genome systems to enhance secondary metabolite production.


Assuntos
Actinomycetales , Preparações Farmacêuticas , Streptomyces , Biotecnologia , Engenharia Metabólica , Streptomyces/genética
6.
Front Oncol ; 10: 583781, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33381454

RESUMO

Recent advances in tumor immunotherapy have made it possible to efficiently unleash immune effectors, reacting against neoplastic cells. Although these approaches primarily aim to eradicate malignancy, immune-related adverse events (irAEs) often influence patients' prognosis, constituting a new spectrum of side effects. Taking into account the typical microenvironment and the intricate equilibrium between the anti-tumor response and the immune cells, the thymoma constitutes a unicum in the immune-oncology field. We report a fatal immune-mediated adverse events' storm in a thymoma patient treated with Pembrolizumab, leading to hepatotoxicity accompanied by lymphocytosis, thrombocytopenia, and thyroid dysfunction, unveiling a novel potential pathophysiological effect of immunotherapy. The clinical proficiency of the immune checkpoint inhibitors in thymoma patients warrants timely prevention and management of off-target consequences in order to optimize this promising therapeutic option. This case report describes a unique consequence of irAEs, emerging as a red flag warranting a multidisciplinary approach.

7.
Molecules ; 25(21)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114231

RESUMO

16α-Hydroxyprednisolone, an anti-inflammatory drug, could be potentially obtained from hydrocortisone bioconversion by combining a 1,2-dehydrogenation reaction performed by Arthrobacter simplexATCC31652 with a 16α-hydroxylation reaction by Streptomyces roseochromogenes ATCC13400. In this study we tested, for the first time, potential approaches to couple the two reactions using similar pH and temperature conditions for hydrocortisone bioconversion by the two strains. The A. simplex capability to 1,2-dehydrogenate the 16α-hydroxyhydrocortisone, the product of S. roseochromogenes transformation of hydrocortisone, and vice versa the capability of S. roseochromogenes to 16α-hydroxylate the prednisolone were assessed. Bioconversions were studied in shake flasks and strain morphology changes were observed by SEM. Whole cell experiments were set up to perform the two reactions in a sequential mode in alternate order or contemporarily at diverse temperature conditions. A. simplex catalyzed either the dehydrogenation of hydrocortisone into prednisolone efficiently or of 16α-hydroxyhydrocortisone into 16α-hydroxyprednisolone in 24 h (up to 93.9%). Surprisingly S. roseochromogenes partially converted prednisolone back to hydrocortisone. A 68.8% maximum of 16α-hydroxyprednisolone was obtained in 120-h bioconversion by coupling whole cells of the two strains at pH 6.0 and 26 °C. High bioconversion of hydrocortisone into 16α-hydroxyprednisolone was obtained for the first time by coupling A. simplex and S. roseochromogenes.


Assuntos
Arthrobacter/metabolismo , Biotecnologia/métodos , Hidrocortisona/metabolismo , Prednisolona/metabolismo , Biotransformação
8.
Appl Microbiol Biotechnol ; 103(16): 6771-6782, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31222385

RESUMO

Heparin and chondroitin sulfate are used as anti-thrombic and anti-osteoarthritis drugs, respectively, but their pharmacological actions depend on their structural characteristics such as their sulfation grade and their molecular weight. In the last years, new fermentation-based biotechnological approaches have tried to obtain heparin and chondroitin sulfate starting from the heparosan and chondroitin-like capsular polysaccharides produced by Escherichia coli K5 and K4. The study of the microbial capsular polysaccharide molecular weight is critical to obtain nature-like or structural tailor cut glycosaminoglycan homologues. However, so far, it has been scarcely investigated. In this paper, for the first time, a new protocol was set up to determine the molecular weights of the capsular polysaccharides of three wild-type and three engineered E. coli K5 and K4 strains. The protocol includes a small-scale downstream train to purify the intact polysaccharides, directly from the fermentation broth supernatants, by using ultrafiltration membranes and anion exchange chromatography, and it couples size exclusion chromatography analyses with triple detector array. In the purification high recovery (> 85.0%) and the removal of the main contaminant, the lipopolysaccharide, were obtained. The averaged molecular weights of the wild-type capsular polysaccharides ranged from 51.3 to 90.9 kDa, while the engineered strains produced polysaccharides with higher molecular weights, ranging from 68.4 to 130.6 kDa, but with similar polydispersity values between 1.1 and 1.5.


Assuntos
Condroitina/química , Dissacarídeos/química , Escherichia coli/química , Engenharia Metabólica , Polissacarídeos Bacterianos/química , Condroitina/metabolismo , Cromatografia em Gel , Meios de Cultura/química , Dissacarídeos/metabolismo , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Peso Molecular , Polissacarídeos Bacterianos/metabolismo , Ultrafiltração
9.
Cancers (Basel) ; 11(2)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682873

RESUMO

Liver metastases (LM) are often consequences of colo-rectal cancer (CRC)and the majority of patients have unresectable LM. Oxaliplatin-based intravenous chemotherapy represents the gold standard treatment for CRC. Intravenous oxaliplatin has several side effects i.e., nephrologic, hematologic and neurological toxicity. Moreover, hepatic arterial infusion (HAI) of antitumor drugs deeply modifies the treatment of LMCRC due to the knowledge that LM are perfused by the hepatic artery network, whereas healthy tissue is perfused by the portal vein. Therefore, oxaliplatin-based HAI becomes an interesting possibility to treat LMCRC. The aim of this review is to shed light on the important impact of the oxaliplatin-based chemotherapy from a non-conventional clinical point of view, considering that, being universally accepted its antitumor effect if administered intravenously, fragmentary information are known about its clinical applications and benefits deriving from intra-arterial administration in loco-regional chemotherapy.

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