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1.
J Breast Imaging ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912622

RESUMO

BACKGROUND: High mammographic density increases breast cancer risk and reduces mammographic sensitivity. We reviewed evidence on accuracy of supplemental MRI for women with dense breasts at average or increased risk. METHODS: PubMed and Embase were searched 1995-2022. Articles were included if women received breast MRI following 2D or tomosynthesis mammography. Risk of bias was assessed using QUADAS-2. Analysis used independent studies from the articles. Fixed-effect meta-analytic summaries were estimated for predefined groups (PROSPERO: 230277). RESULTS: Eighteen primary research articles (24 studies) were identified in women aged 19-87 years. Breast density was heterogeneously or extremely dense (BI-RADS C/D) in 15/18 articles and extremely dense (BI-RADS D) in 3/18 articles. Twelve of 18 articles reported on increased-risk populations. Following 21 440 negative mammographic examinations, 288/320 cancers were detected by MRI. Substantial variation was observed between studies in MRI cancer detection rate, partly associated with prevalent vs incident MRI exams (prevalent: 16.6/1000 exams, 12 studies; incident: 6.8/1000 exams, 7 studies). MRI had high sensitivity for mammographically occult cancer (20 studies with at least 1-year follow-up). In 5/18 articles with sufficient data to estimate relative MRI detection rate, approximately 2 in 3 cancers were detected by MRI (66.3%, 95% CI, 56.3%-75.5%) but not mammography. Positive predictive value was higher for more recent studies. Risk of bias was low in most studies. CONCLUSION: Supplemental breast MRI following negative mammography in women with dense breasts has breast cancer detection rates of ~16.6/1000 at prevalent and ~6.8/1000 at incident MRI exams, considering both high and average risk settings.

2.
Eur J Pharm Biopharm ; 201: 114348, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38844097

RESUMO

Nitric oxide (NO) / ß-Lapachone (Lap) combined therapy by causing oxidative stress is an effective tumor therapy strategy. Herein, a dual-responsive lipid nanoparticles (LNPs) LSNO for NO / Lap co-delivery were constructed from the zinc-coordinated lipid (DSNO(Zn)) and the hydrophobic drug Lap in the presence of helper lipids (DOPE and DSPE-PEG2000). The zinc-coordinated structure in LSNO might elevate the Zn2+ content in tumor cells, contributing to antioxidant imbalance. The fluorescent assays proved the light-triggered NO release and fluorescent self-reporting abilities of LSNO. In addition, the LNPs had good drug release behavior under high concentration of GSH, indicating the NO / drug co-delivery capacity. In vitro antitumor assays showed that the NO / Lap combination treatment group could induce more significant tumor cell growth inhibition and cell apoptosis than individual NO or Lap treatment. The following mechanism studies revealed that NO / Lap combination treatment led to distinct oxidative stress by producing reactive oxygen species (ROS) and peroxynitrite anion (ONOO-). On the other hand, the intracellular redox balance could be further disrupted by Lap-induced NADPH consumption and Zn2+ / NO-induced reductase activities downregulation, thus promoting the degree of cell damage. Besides, it was also found that NO and Lap could directly damage nuclear DNA and induce mitochondrial dysfunction, thereby leading to caspase-3 activation and tumor cell death. These results proved that LSNO could serve as a promising multifunctional tumor therapy platform.


Assuntos
Nanopartículas , Naftoquinonas , Óxido Nítrico , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio , Naftoquinonas/administração & dosagem , Naftoquinonas/farmacologia , Naftoquinonas/química , Óxido Nítrico/metabolismo , Óxido Nítrico/administração & dosagem , Humanos , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Zinco/química , Zinco/administração & dosagem , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Lipídeos/química , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia
3.
Photodiagnosis Photodyn Ther ; 48: 104237, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38871017

RESUMO

PURPOSE: To report the use of anterior segment optical coherence tomography (AS-OCT) for superficial keratectomy (SK) in anterior corneal opacity. METHODS: The characteristics of 43 eyes (39 patients) with various lesions responsible for anterior corneal opacity were included in this retrospective non-comparative study. AS-OCT was performed on all eyes before surgery. The thickness of corneal opacity and the underlying healthy stroma were measured. SK was performed on each individual. RESULTS: Four types of anterior corneal opacity were evaluated, including corneal degeneration (26/43), Reis-Bücklers corneal dystrophy (8/43), alkali burn (1/43) and corneal tumors (8/43). Based on AS-OCT images, all eyes showed abnormal hyper-reflective signals in the superficial cornea to less than one-third of the normal corneal thickness in the deepest corneal opacity. All 43 eyes underwent an SK procedure. In addition, 1 eye with alkali burns and 7 eyes with corneal tumors were combined with amniotic membrane transplantation. All eyes restored transparency without significant complications. CONCLUSION: AS-OCT is a valuable method for objective preoperative and noninvasive assessments of anterior corneal opacities and is useful for guiding SK.

4.
FASEB J ; 38(10): e23705, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38805171

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with a notoriously dismal prognosis. As a competitive inhibitor of DNA synthesis, gemcitabine is the cornerstone drug for treating PDAC at all stages. The therapeutic effect of gemcitabine, however, is often hindered by drug resistance, and the underlying mechanisms remain largely unknown. It is unclear whether their response to chemotherapeutics is regulated by endocrine regulators, despite the association between PDAC risk and endocrine deregulation. Here, we show that prolactin receptor (PRLR) synergizes with gemcitabine in both in vitro and in vivo treatment of PDAC. Interestingly, PRLR promotes the expression of miR-4763-3p and miR-3663-5p, two novel miRNAs whose functions are unknown. Furthermore, the analysis of transcriptome sequencing data of tumors from lactating mouse models enriches the PPP pathway, a multifunctional metabolic pathway. In addition to providing energy, the PPP pathway mainly provides a variety of raw materials for anabolism. We demonstrate that two key enzymes of the pentose phosphate pathway (PPP), G6PD and TKT, are directly targeted by miR-4763-3p and miR-3663-5p. Notably, miR-4763-3p and miR-3663-5p diminish the nucleotide synthesis of the PPP pathway, thereby increasing gemcitabine sensitivity. As a result, PRLR harnesses these two miRNAs to suppress PPP and nucleotide synthesis, subsequently elevating the gemcitabine sensitivity of PDAC cells. Also, PDAC tissues and tumors from LSL-KrasG12D/+, LSL-Trp53R172H/+, and PDX1-cre (KPC) mice exhibit downregulation of PRLR. Bisulfite sequencing of PDAC tissues revealed that PRLR downregulation is due to epigenetic methylation. In this study, we show for the first time that the endocrine receptor PRLR improves the effects of gemcitabine by boosting two new miRNAs that block the PPP pathway and nucleotide synthesis by inhibiting two essential enzymes concurrently. The PRLR-miRNAs-PPP axis may serve as a possible therapeutic target to supplement chemotherapy advantages in PDAC.


Assuntos
Carcinoma Ductal Pancreático , Desoxicitidina , Gencitabina , Glucosefosfato Desidrogenase , MicroRNAs , Neoplasias Pancreáticas , Receptores da Prolactina , Animais , Feminino , Humanos , Camundongos , Antimetabólitos Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucosefosfato Desidrogenase/metabolismo , Glucosefosfato Desidrogenase/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Receptores da Prolactina/metabolismo , Receptores da Prolactina/genética , Camundongos Nus
5.
Cancer Immunol Immunother ; 73(6): 115, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38693304

RESUMO

In the malignant progression of tumors, there is deposition and cross-linking of collagen, as well as an increase in hyaluronic acid content, which can lead to an increase in extracellular matrix stiffness. Recent research evidence have shown that the extracellular matrix plays an important role in angiogenesis, cell proliferation, migration, immunosuppression, apoptosis, metabolism, and resistance to chemotherapeutic by the alterations toward both secretion and degradation. The clinical importance of tumor-associated macrophage is increasingly recognized, and macrophage polarization plays a central role in a series of tumor immune processes through internal signal cascade, thus regulating tumor progression. Immunotherapy has gradually become a reliable potential treatment strategy for conventional chemotherapy resistance and advanced cancer patients, but the presence of immune exclusion has become a major obstacle to treatment effectiveness, and the reasons for their resistance to these approaches remain uncertain. Currently, there is a lack of exact mechanism on the regulation of extracellular matrix stiffness and tumor-associated macrophage polarization on immune exclusion. An in-depth understanding of the relationship between extracellular matrix stiffness, tumor-associated macrophage polarization, and immune exclusion will help reveal new therapeutic targets and guide the development of clinical treatment methods for advanced cancer patients. This review summarized the different pathways and potential molecular mechanisms of extracellular matrix stiffness and tumor-associated macrophage polarization involved in immune exclusion and provided available strategies to address immune exclusion.


Assuntos
Matriz Extracelular , Neoplasias , Macrófagos Associados a Tumor , Humanos , Matriz Extracelular/metabolismo , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/metabolismo , Neoplasias/terapia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Animais , Microambiente Tumoral/imunologia , Imunoterapia/métodos , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo
7.
World J Surg ; 48(1): 48-58, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38686802

RESUMO

BACKGROUND: Major abdominal surgery is associated with a high rate of post-operative complications with increased risk of adverse surgical outcomes due to the presence of frailty. This study aims to evaluate the effectiveness of the multimodal Recovery of Surgery in the Elderly (ROSE) prehabilitation program with supervised exercise in mitigating postoperative functional decline when compared to standard care. METHOD: The ROSE program enrolled ambulant patients who were 65 years and above, had a Clinical Frailty Scale score of 4 or more and were planned for major abdominal surgery. Participation in supervised exercise sessions before surgery were compared with standard physiotherapy advice. The primary outcome was 6-min walk test (6MWT) distance assessed at baseline, after prehabilitation and 30 days follow-up after surgery. Secondary outcomes included physical performance, length of hospital stay and postoperative morbidity. RESULTS: Data from 74 eligible patients, 37 in each group, were included. Median age was 78 years old. Forty-two patients (22 in Prehab group and 20 in control group) with complete 6MWT follow-up data at 30 days follow-up were analysed for outcomes. Most patients underwent laparoscopic surgery (63.5%) and almost all of the surgeries were for abdominal malignancies (97.3%). The Prehab group had an increase in 6MWT distance at the 30-day follow up, from a baseline mean (SD) of 277.4 (125) m to 287.6 (143.5) m (p = 0.415). The 6MWT distance in the control group decreased from a baseline mean (SD) of 281.7 (100.5) m to 260.1 (78.6) m at the 30-day follow up (p = 0.086). After adjusting for baseline 6MWT distance and frailty score, the Prehab group had significantly higher 6MWT distance at 30-day follow-up than control (difference in adjusted means 41.7 m, 95% confidence interval 8.7-74.8 m, p = 0.015). There were no significant between-group differences in the secondary outcomes. CONCLUSION: A multimodal prehabilitation program with supervised exercise within a short time frame can improve preoperative functional capacity and maintain baseline functional capacity in frail older adults undergoing major abdominal surgery.


Assuntos
Complicações Pós-Operatórias , Exercício Pré-Operatório , Humanos , Idoso , Feminino , Masculino , Idoso de 80 Anos ou mais , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Idoso Fragilizado , Abdome/cirurgia , Resultado do Tratamento , Recuperação de Função Fisiológica , Terapia por Exercício/métodos , Fragilidade , Estudos Prospectivos
8.
Healthcare (Basel) ; 12(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38610227

RESUMO

Despite curative treatment and discharge from acute hospital settings, breast cancer patients often have cancer- and treatment-related morbidity which impairs them from returning to work. Hence, the role of community-based return to work rehabilitation programs is important to help these patients transition back to work. This was a retrospective cohort study involving patients with breast cancer conducted at a community-based cancer rehabilitation center. Patients were involved in an interdisciplinary vocational rehabilitation program involving physiatrists, occupational therapists, physiotherapists and social workers. We recruited 63 patients for this study cohort, with 46 (73.0%) patients ≤ 60 years old. After undergoing the rehabilitation program, there were 37 (58.7%) participants who successfully returned to work. These participants returned to work at either within 6 months (27.0%), 12 months (29.7%) or 24 months (43.2%) after enrollment into the program, with a majority enrolling in white collar jobs. Multivariate regression analysis revealed that significant negative factors for return to work were advanced stage of cancer (p = 0.004), along with clinically significant fatigue, measured on the Brief Fatigue Inventory (p < 0.001). However, perceived work ability (p = 0.020) was found to be a positive factor.

9.
Eur Respir J ; 63(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38636970

RESUMO

BACKGROUND: Up to 50% of those attending for low-dose computed tomography screening for lung cancer continue to smoke and co-delivery of smoking cessation services alongside screening may maximise clinical benefit. Here we present data from an opt-out co-located smoking cessation service delivered alongside the Yorkshire Lung Screening Trial (YLST). METHODS: Eligible YLST participants were offered an immediate consultation with a smoking cessation practitioner (SCP) at their screening visit with ongoing smoking cessation support over subsequent weeks. RESULTS: Of 2150 eligible participants, 1905 (89%) accepted the offer of an SCP consultation during their initial visit, with 1609 (75%) receiving ongoing smoking cessation support over subsequent weeks. Uptake of ongoing support was not associated with age, ethnicity, deprivation or educational level in multivariable analyses, although men were less likely to engage (adjusted OR (ORadj) 0.71, 95% CI 0.56-0.89). Uptake was higher in those with higher nicotine dependency, motivation to stop smoking and self-efficacy for quitting. Overall, 323 participants self-reported quitting at 4 weeks (15.0% of the eligible population); 266 were validated by exhaled carbon monoxide (12.4%). Multivariable analyses of eligible smokers suggested 4-week quitting was more likely in men (ORadj 1.43, 95% CI 1.11-1.84), those with higher motivation to quit and previous quit attempts, while those with a stronger smoking habit in terms of cigarettes per day were less likely to quit. CONCLUSIONS: There was high uptake for co-located opt-out smoking cessation support across a wide range of participant demographics. Protected funding for integrated smoking cessation services should be considered to maximise programme equity and benefit.


Assuntos
Abandono do Hábito de Fumar , Tabagismo , Masculino , Humanos , Abandono do Hábito de Fumar/métodos , Serviços de Saúde Comunitária , Pulmão , Tomografia
10.
Acta Pharmacol Sin ; 45(6): 1160-1174, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38438581

RESUMO

Nicotinic acetylcholine receptors (nAChRs) regulate pain pathways with various outcomes depending on receptor subtypes, neuron types, and locations. But it remains unknown whether α4ß2 nAChRs abundantly expressed in the substantia nigra pars reticulata (SNr) have potential to mitigate hyperalgesia in pain states. We observed that injection of nAChR antagonists into the SNr reduced pain thresholds in naïve mice, whereas injection of nAChR agonists into the SNr relieved hyperalgesia in mice, subjected to capsaicin injection into the lower hind leg, spinal nerve injury, chronic constriction injury, or chronic nicotine exposure. The analgesic effects of nAChR agonists were mimicked by optogenetic stimulation of cholinergic inputs from the pedunculopontine nucleus (PPN) to the SNr, but attenuated upon downregulation of α4 nAChRs on SNr GABAergic neurons and injection of dihydro-ß-erythroidine into the SNr. Chronic nicotine-induced hyperalgesia depended on α4 nAChRs in SNr GABAergic neurons and was associated with the reduction of ACh release in the SNr. Either activation of α4 nAChRs in the SNr or optogenetic stimulation of the PPN-SNr cholinergic projection mitigated chronic nicotine-induced hyperalgesia. Interestingly, mechanical stimulation-induced ACh release was significantly attenuated in mice subjected to either capsaicin injection into the lower hind leg or SNI. These results suggest that α4 nAChRs on GABAergic neurons mediate a cholinergic analgesic circuit in the SNr, and these receptors may be effective therapeutic targets to relieve hyperalgesia in acute and chronic pain, and chronic nicotine exposure.


Assuntos
Neurônios GABAérgicos , Hiperalgesia , Camundongos Endogâmicos C57BL , Receptores Nicotínicos , Animais , Receptores Nicotínicos/metabolismo , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/fisiologia , Masculino , Hiperalgesia/metabolismo , Hiperalgesia/tratamento farmacológico , Camundongos , Parte Reticular da Substância Negra/metabolismo , Parte Reticular da Substância Negra/efeitos dos fármacos , Nicotina/farmacologia , Analgésicos/farmacologia , Agonistas Nicotínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Capsaicina/farmacologia , Acetilcolina/metabolismo , Optogenética , Limiar da Dor/efeitos dos fármacos
11.
Oncogenesis ; 13(1): 10, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424455

RESUMO

Endocrine receptors play an essential role in tumor metabolic reprogramming and represent a promising therapeutic avenue in pancreatic ductal adenocarcinoma (PDAC). PDAC is characterized by a nutrient-deprived microenvironment. To meet their ascendant energy demands, cancer cells can internalize extracellular proteins via macropinocytosis. However, the roles of endocrine receptors in macropinocytosis are not clear. In this study, we found that progesterone receptor (PGR), a steroid-responsive nuclear receptor, is highly expressed in PDAC tissues obtained from both patients and transgenic LSL-KrasG12D/+; LSL-Trp53R172H/+; PDX1-cre (KPC) mice. Moreover, PGR knockdown restrained PDAC cell survival and tumor growth both in vitro and in vivo. Genetic and pharmacological PGR inhibition resulted in a marked attenuation of macropinocytosis in PDAC cells and subcutaneous tumor models, indicating the involvement of this receptor in macropinocytosis regulation. Mechanistically, PGR upregulated CDC42, a critical regulator in macropinocytosis, through PGR-mediated transcriptional activation. These data deepen the understanding of how the endocrine system influences tumor progression via a non-classical pathway and provide a novel therapeutic option for patients with PDAC.

12.
Br J Radiol ; 97(1154): 469-476, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308037

RESUMO

OBJECTIVES: To evaluate radiation doses for all low-dose CT scans performed during the first year of a lung screening trial. METHODS: For all lung screening scans that were performed using a CT protocol that delivered image quality meeting the RSNA QIBA criteria, radiation dose metrics, participant height, weight, gender, and age were recorded. Values of volume CT dose index (CTDIvol) and dose length product (DLP) were evaluated as a function of weight in order to assess the performance of the scan protocol across the participant cohort. Calculated effective doses were used to establish the additional lifetime attributable cancer risks arising from trial scans. RESULTS: Median values of CTDIvol, DLP, and effective dose (IQR) from the 3521 scans were 1.1 mGy (0.70), 42.4 mGycm (24.9), and 1.15 mSv (0.67), whilst for 60-80kg participants the values were 1.0 mGy (0.30), 35.8 mGycm (11.4), and 0.97 mSv (0.31). A statistically significant correlation between CTDIvol and weight was identified for males (r = 0.9123, P < .001) and females (r = 0.9052, P < .001), however, the effect of gender on CTDIvol was not statistically significant (P = .2328) despite notable differences existing at the extremes of the weight range. The additional lifetime attributable cancer risks from a single scan were in the range 0.001%-0.006%. CONCLUSIONS: Low radiation doses can be achieved across a typical lung screening cohort using scan protocols that have been shown to deliver high levels of image quality. The observed dose levels may be considered as typical values for lung screening scans on similar types of scanners for an equivalent participant cohort. ADVANCES IN KNOWLEDGE: Presentation of typical radiation dose levels for CT lung screening examinations in a large UK trial. Effective radiation doses can be of the order of 1 mSv for standard sized participants. Lifetime attributable cancer risks resulting from a single low-dose CT scan did not exceed 0.006%.


Assuntos
Neoplasias Pulmonares , Pulmão , Feminino , Humanos , Masculino , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Doses de Radiação , Tórax , Tomografia Computadorizada por Raios X/métodos , Ensaios Clínicos como Assunto
13.
Research (Wash D C) ; 7: 0300, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38314086

RESUMO

Ferroptosis, a nonapoptotic form of cell death, is an emerging potential therapeutic target for various diseases, including cancer. However, the role of ferroptosis in pancreatic cancer remains poorly understood. Pancreatic ductal adenocarcinoma (PDAC) is characterized by a poor prognosis and chemotherapy resistance, attributed to its high Kirsten rats arcomaviral oncogene homolog mutation rate and severe nutritional deficits resulting from a dense stroma. Several studies have linked rat sarcoma (RAS) mutations to ferroptosis, suggesting that inducing ferroptosis may be an effective strategy against oncogenic RAS-bearing tumors. We investigated the role of Family With Sequence Similarity 60 Member A (FAM60A) in this study, a protein closely associated with a poor prognosis and highly expressed in PDAC and tumor tissue from KrasG12D/+;Trp53R172H/+; Pdx1-Cre mice, in regulating ferroptosis, tumor growth, and gemcitabine sensitivity in vitro and in vivo. Our results demonstrate that FAM60A regulates 3 essential metabolic enzymes, ACSL1/4 and GPX4, to protect PDAC cells from ferroptosis. Furthermore, we found that YY1 transcriptionally regulates FAM60A expression by promoting its transcription, and the Hippo-YY1 pathway is restricted in the low-amino-acid milieu in the context of nutrient deprivation, leading to downstream suppression of peroxisome proliferator-activated receptor and ACSL1/4 and activation of GPX4 pathways. Importantly, FAM60A knockdown sensitized PDAC cells to gemcitabine treatment. A new understanding of FAM60A transcriptional regulation pattern in PDAC and its dual function in ferroptosis reliever and chemotherapy resistance is provided by our study. Targeting FAM60A may therefore offer a promising therapeutic approach for PDAC by simultaneously addressing 2 major features of the disease (high RAS mutation rate and tumor microenvironment nutrient deficiency) and preventing tumor cell metabolic adaptation.

14.
Angew Chem Int Ed Engl ; 63(12): e202318784, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38291557

RESUMO

Plitidepsin (or dehydrodidemnin B), an approved anticancer drug, belongs to the didemnin family of cyclic depsipeptides, which are found in limited quantities in marine tunicate extracts. Herein, we introduce a new approach that integrates microbial and chemical synthesis to generate plitidepsin and its analogues. We screened a Tistrella strain library to identify a potent didemnin B producer, and then introduced a second copy of the didemnin biosynthetic gene cluster into its genome, resulting in a didemnin B titer of approximately 75 mg/L. Next, we developed two straightforward chemical strategies to convert didemnin B into plitidepsin, one of which involved a one-step synthetic route giving over 90 % overall yield. Furthermore, we synthesized 13 new didemnin derivatives and three didemnin probes, enabling research into structure-activity relationships and interactions between didemnin and proteins. Our study highlights the synergistic potential of biosynthesis and chemical synthesis in overcoming the challenge of producing complex natural products sustainably and at scale.


Assuntos
Antineoplásicos , Depsipeptídeos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/metabolismo , Depsipeptídeos/farmacologia , Antineoplásicos/farmacologia , Relação Estrutura-Atividade
15.
Reprod Sci ; 31(7): 1868-1880, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38263477

RESUMO

Ovarian cancer (OV) is a highly aggressive malignancy with poor prognosis due to recurrence and drug resistance. Therefore, it is imperative to investigate the key molecular mechanisms underlying OV progression in order to develop promising diagnostic and therapeutic interventions. Although the importance of hematological and neurological expressed 1 (HN1) protein in hemopoietic cell and neurological development has been well-established, its function in cancer, particularly in OV, remains uncertain. In this study, we compared the expression of HN1 in ovarian cancers and para-tumor tissues and predicted potential related signaling pathways through enrichment analysis. In order to confirm the role of HN1 in vitro and vivo, we carried out a variety of experiments including bioinformation analysis, colony formation, flow cytometry analysis, and subcutaneous tumor models. The results demonstrated that HN1 was upregulated in OV and was negatively associated with clinical prognosis. Moreover, we observed that HN1 enhances cell proliferation, migration, and drug resistance, while suppressing apoptosis in OV cells. Notably, we discovered that HN1 functions as a novel regulator of mTOR pathways. Our findings suggest that HN1-mediated mTOR regulation facilitates OV advancement and targeting HN1 could provide a promising therapeutic approach for clinical OV treatment.


Assuntos
Proliferação de Células , Neoplasias Ovarianas , Transdução de Sinais , Serina-Treonina Quinases TOR , Feminino , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Humanos , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Animais , Progressão da Doença , Movimento Celular , Fucosiltransferases/metabolismo , Fucosiltransferases/genética , Apoptose/fisiologia , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Camundongos , Camundongos Nus
16.
Int Dent J ; 74(2): 246-252, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37666687

RESUMO

OBJECTIVES: The objective of this randomised controlled trial was to compare the periodontal healing at the distal of the adjacent second molar after coronectomy or surgical removal and the surgical morbidities of the 2 techniques. METHODS: This is a pilot study of a split-mouth randomised clinical trial comparing the periodontal healing of the adjacent second molar after coronectomy or total removal of lower third molars, which was registered with the University of Hong Kong Clinical Trial Centre as HKUCTR-2948 on 21 February 2020. Cone beam computed tomography (CBCT) scans were taken preoperatively and at 6 months postoperatively. Changes in the bone level from the cemento-enamel junction, periodontal probing depth (PPD), and clinical attachment level (CAL) at the distal of the adjacent second molar were compared. Surgical morbidities in terms of pain, infection, neurologic deficit, root exposure, and need for second surgery for removal were assessed. RESULTS: Forty patients (22 male, 18 female) with mean age of 26.7 years were evaluated at 6 months postoperatively. Both coronectomy and total removal groups demonstrated statistically significant reduction in PPD and CAL. There was an alveolar bone gain of 1.28 ± 0.88 mm in the coronectomy group and 1.13 ± 0.73mm in the control group, which was statistically significant (P < .001 for both groups). CONCLUSIONS: Early findings show the periodontal healing at the adjacent second molar of coronectomy was as good as that of total removal of lower third molar. There were no differences in terms of surgical morbidities between both groups.


Assuntos
Dente Serotino , Dente Impactado , Humanos , Masculino , Feminino , Adulto , Dente Serotino/diagnóstico por imagem , Dente Serotino/cirurgia , Projetos Piloto , Extração Dentária , Mandíbula/cirurgia , Dente Molar/cirurgia , Dente Impactado/cirurgia
17.
Ann Am Thorac Soc ; 21(3): 393-401, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37962906

RESUMO

Rationale: The relationship between symptoms, measured using a validated disease-specific questionnaire, and longitudinal exacerbation risk has not been demonstrated in bronchiectasis. Objectives: The aim of this study is to investigate whether baseline symptoms, assessed using the Quality-of-Life Bronchiectasis Respiratory Symptom Scale (QoL-B-RSS) and its individual component scores, could predict future exacerbation risk in patients with bronchiectasis. Methods: The study included 436 adults with bronchiectasis from three tertiary hospitals. Symptoms were measured using the QoL-B-RSS, with scores ranging from 0 to 100, where lower scores indicated more severe symptoms. We examined whether symptoms as continuous measures were associated with the risk of exacerbation over 12 months. The analysis was also repeated for individual components of the QoL-B-RSS score. Results: The baseline QoL-B-RSS score was associated with an increased risk of exacerbations (rate ratio, 1.25 for each 10-point decrease; 95% confidence interval [CI], 1.15-1.35; P < 0.001), hospitalizations (rate ratio, 1.24; 95% CI, 1.05-1.43; P = 0.02), and reduced time to the first exacerbation (hazard ratio, 1.12; 95% CI, 1.03-1.21; P = 0.01) over 12 months, even after adjusting for relevant confounders, including exacerbation history. The QoL-B-RSS score was comparable to exacerbation history in its association with future frequent exacerbations (defined as three or more exacerbations per year) and hospitalization (area under the curve, 0.86 vs. 0.84; P = 0.46; and area under the curve, 0.81 vs. 0.83; P = 0.41, respectively). Moreover, patients with more severe symptoms in the majority of individual components of the QoL-B-RSS were more likely to experience exacerbations. Conclusions: Symptoms can serve as useful indicators for identifying patients at increased risk of exacerbation in bronchiectasis. Beyond relying solely on exacerbation history, a comprehensive assessment of symptoms could facilitate timely and cost-effective implementation of interventions for exacerbation prevention.


Assuntos
Bronquiectasia , Qualidade de Vida , Adulto , Humanos , Estudos Prospectivos , Bronquiectasia/complicações , Hospitalização , Centros de Atenção Terciária
18.
Adv Sci (Weinh) ; 11(4): e2306044, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38032137

RESUMO

The assembly line biosynthesis of the powerful anticancer-antiviral didemnin cyclic peptides is proposed to follow a prodrug release mechanism in Tristella bacteria. This strategy commences with the formation of N-terminal prodrug scaffolds and culminates in their cleavage during the cellular export of the mature products. In this study, a comprehensive exploration of the genetic and biochemical aspects of the enzymes responsible for both the assembly and cleavage of the acylated peptide prodrug scaffolds is provided. This process involves the assembly of N-acyl-polyglutamine moieties orchestrated by the nonribosomal peptide synthetase DidA and the cleavage of these components at the post-assembly stage by DidK, a transmembrane CAAX hydrolase homolog. The findings not only shed light on the complex prodrug mechanism that underlies the synthesis and secretion of didemnin compounds but also offer novel insights into the expanded role of CAAX hydrolases in microbes. Furthermore, this knowledge can be leveraged for the strategic design of genome mining approaches aimed at discovering new bioactive natural products that employ similar prodrug biochemical strategies.


Assuntos
Depsipeptídeos , Pró-Fármacos , Peptídeo Hidrolases , Endopeptidases , Pró-Fármacos/farmacologia
19.
World J Gastroenterol ; 29(44): 5919-5934, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38111505

RESUMO

BACKGROUND: The role of Tousled-like kinase 1 (TLK1) in in gastric cancer (GC) remains unclear. AIM: To investigate the expression, biological function, and underlying mechanisms of TLK1 in GC. METHODS: We measured TLK1 protein expression levels and localized TLK1 in GC cells and tissues by western blot and immunofluorescence, respectively. We transfected various GC cells with lentiviruses to create TLK1 overexpression and knockdown lines and established the functional roles of TLK1 through in vitro colony formation, 5-ethynyl-2`-deoxyuridine, and Transwell assays as well as flow cytometry. We applied bioinformatics to elucidate the signaling pathways associated with TLK1. We performed in vivo validation of TLK1 functions by inducing subcutaneous xenograft tumors in nude mice. RESULTS: TLK1 was significantly upregulated in GC cells and tissues compared to their normal counterparts and was localized mainly to the nucleus. TLK1 knockdown significantly decreased colony formation, proliferation, invasion, and migration but increased apoptosis in GC cells. TLK1 overexpression had the opposite effects. Bioinformatics revealed, and subsequent experiments verified, that the tumor growth factor-beta signaling pathway was implicated in TLK1-mediated GC progression. The in vivo assays confirmed that TLK1 promotes tumorigenesis in GC. CONCLUSION: The findings of the present study indicated that TLK1 plays a crucial role in GC progression and is, therefore, promising as a therapeutic target against this disease.


Assuntos
Neoplasias Gástricas , Animais , Camundongos , Humanos , Neoplasias Gástricas/patologia , Camundongos Nus , Transdução de Sinais , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proliferação de Células , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Movimento Celular , Proteínas Serina-Treonina Quinases/metabolismo
20.
J Pain Res ; 16: 2713-2728, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37577159

RESUMO

Background: The pain-fatigue-sleep disturbance symptom cluster is commonly experienced by breast cancer patients, and a variety of nonpharmacological interventions are used to treat this symptom cluster. Objective: To compare the efficacy of nonpharmacological interventions in improving the symptoms of the pain-fatigue-sleep disturbance symptom cluster in breast cancer patients. Methods: A comprehensive literature search was conducted in the PubMed, EMBASE, Cochrane Library, CINAHL, CNKI, and Wanfang databases to identify randomized controlled studies from database inception to May 2022. Two reviewers independently performed data retrieval and risk of bias assessments. The consistency model was used to conduct network meta-analyses (NMA) based on the frequentist framework to assess the interventions, which were ranked by the surface under the cumulative ranking curve (SUCRA). Finally, the CINeMA application was used to evaluate the results of the NMA and the evidence of quality. The results Twenty-three eligible studies assessing 14 interventions were included. According to SUCRA values, among the management effects of the three symptoms, the effect of progressive muscle relaxation (PMR) ranked first, followed by mindfulness-based stress reduction (MBSR). The overall evidence quality of our study ranges from very low to moderate. Conclusion: PMR and MBSR were effective interventions for the pain-fatigue-sleep disturbance symptom cluster in breast cancer patients. Clinical recommendations prioritize PMR for symptom management, followed by MBSR. However, this should be interpreted cautiously, as the confidence in the evidence was not high.

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