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3.
bioRxiv ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37131786

RESUMO

Malignant astrocytomas are aggressive glioma tumors characterized by extensive hypoxia-induced, mito-chondria-dependent changes such as altered respiration, increased chymotrypsin-like (CT-L) proteasome activity, decreased apoptosis, drug resistance, stemness and increased invasiveness. Mitochondrial Lon Peptidase I (LonP1) overexpression and increased CT-L proteasome inhibitors activity are the biomarkers of aggressive high grade glioma phenotype, poor prognosis and found to be associated with recurrence and poor patient survival, and drugs targeting either LonP1 or the CT-L activity have anti-glioma activity in pre-clinical models. We here for the first time introduced and evaluated a novel small molecule, BT317, derived from coumarinic compound 4 (CC4) using structure-activity modeling which we found to inhibit both LonP1 and CT-L proteasome activity. Using gain-of-function and loss-of-function genetic models, we dis-covered that BT317 is more effective than the individual LonP1 or CT-L inhibition in increasing reactive oxy-gen species (ROS) generation and inducing apoptosis in high-grade astrocytoma lines. In vitro, BT317 had activity as a single agent but, more importantly, enhanced synergy with the standard of care commonly used chemotherapeutic temozolomide (TMZ). In orthotopic xenograft, patient derived glioma models, BT317 was able to cross the blood-brain barrier, to show selective activity at the tumor site and to demonstrate therapeutic efficacy both as a single agent and in combination with TMZ. BT317 defines an emerging class of dual LonP1, and CT-L proteasome inhibitors exhibited promising anti-tumor activity and could be a promising candidate for clinical translation in the space of malignant astrocytoma therapeutics.

4.
Int J Dermatol ; 63(4): 467-473, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38036942

RESUMO

BACKGROUND: Full-body skin examination (FSE) is a vital practice in the diagnosis of cutaneous malignancy. Precisely how FSE should be conducted with respect to concealed site inclusion remains poorly elucidated. OBJECTIVE: To establish the approach of Australian dermatologists to concealed site examination (CSE). METHODS: A cross-sectional study was performed consisting of an online self-administered 11-question survey delivered to fellows of the Australasian College of Dermatologists. RESULTS: There were 237 respondents. Anogenitalia was the least often examined concealed site (4.6%), and 59.9, 32.9, and 14.3% reported always examining the scalp, breasts, and oral mucosa, respectively. Patient concern was the most frequently cited factor prompting examination, while many cited low incidence of pathology and limited chaperone availability as the main barriers to routine examination of these sites. CONCLUSION: Most Australian dermatologists do not routinely examine breasts, oral mucosal, or anogenital sites as part of an FSE. Emphasis should be made on identifying individual patient risk factors and education regarding self-examination of sensitive sites. A consensus approach to the conduct of the FSE, including concealed sites, is needed to better delineate clinician responsibilities and address medicolegal implications.


Assuntos
Dermatologistas , Neoplasias Cutâneas , Humanos , Estudos Transversais , Austrália , Neoplasias Cutâneas/patologia , Inquéritos e Questionários
5.
Exp Dermatol ; 33(1): e14978, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37971204

RESUMO

Patients with advanced cutaneous squamous cell carcinoma (cSCC) who are not eligible for or who fail to respond to anti-PD1 immunotherapy have few treatment options. Epidermal growth factor receptor (EGFR) inhibitors have been investigated as a therapeutic option for advanced cSCC; however, data are limited to small single-arm trials or retrospective studies. A systematic review and meta-analysis was conducted to PRISMA guidelines (CRD42023394300). Studies reporting on outcomes of EGFR inhibition in advanced cSCC were identified. Objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and adverse event (AE) rate were pooled using a random effects model and the inverse variance method. Twelve studies (six prospective, six retrospective) were identified, representing 324 patients. Pooled ORR was 26% (95% confidence interval [CI] 18-36), median PFS was 4.8 months (95% CI 3.9-6.6) and median OS was 11.7 months (95% CI 9.2-14.1). Any grade AEs occurred in 93% of patients (95% CI 85-97) while grade 3 and higher AEs occurred in 30% (95% CI 14-54). These results were similar between anti-EGFR monoclonal antibodies (MAbs) and tyrosine kinase inhibitors (TKIs). EGFR inhibitors can be considered in patients with advanced cSCC who are contraindicated for or progress on first-line anti-PD1 immunotherapy. Future studies should evaluate their activity and safety following anti-PD1, identify predictive biomarkers for their efficacy and explore combination approaches.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos Retrospectivos , Estudos Prospectivos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/induzido quimicamente , Inibidores de Proteínas Quinases/efeitos adversos , Antineoplásicos/efeitos adversos , Receptores ErbB
6.
Br J Dermatol ; 189(6): 656-663, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37603832

RESUMO

Resident memory T cells (T-RMs) remain in epithelial barrier tissues after antigen exposure and the initial effector phase. These T-RMs provide effective antimicrobial and anticancer immunity; however, pathogenic T-RMs have been shown to mediate various chronic inflammatory disorders in a variety of tissue types. In the skin, T-RMs are referred to as resident cutaneous memory T cells (cT-RMs). Understanding the mechanisms leading to the development and establishment of these cT-RMs populations may allow for targeted treatments that provide durable responses in chronic immune-mediated skin diseases, even after cessation. In this review, we summarize the evidence on cT-RMs as drivers of chronic inflammatory dermatoses, including psoriasis, vitiligo, atopic dermatitis, cutaneous lupus erythematosus and alopecia areata, among others. Data from in vitro, animal model and ex vivo human studies are presented, with a focus on the potential for cT-RMs to trigger acute disease flares, as well as recurrent disease, by establishing an immune 'memory' in the skin. Furthermore, the available data on the potential for existing and novel treatments to affect the development or survival of cT-RMs in the skin are synthesized. The data suggest a dynamic and rapidly growing area in the field of dermatology; however, we also discuss areas in need of greater research to allow for optimal treatment selection for long-term disease control.


Assuntos
Psoríase , Vitiligo , Animais , Humanos , Células T de Memória , Pele , Psoríase/tratamento farmacológico , Administração Cutânea , Doença Crônica
8.
J Hum Nutr Diet ; 36(5): 2099-2107, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37489541

RESUMO

BACKGROUND: Chimeric antigen receptor T (CAR-T) cell therapy is a novel therapy demonstrating durable remissions in patients with refractory or relapsing non-Hodgkin's B-cell lymphoma. Maintaining a patient's nutritional status has been demonstrated to improve outcomes in cancer treatment. However, no studies have investigated how CAR-T therapy affects nutritional status, nor compared its impact with other cancer treatments for this patient group. The primary aim of the present study was to investigate the effect of CAR-T therapy on the prevalence of nutrition impact symptoms (NIS) and nutritional status within 30 days post-treatment of patients with lymphoma compared to a conditioning regimen for autologous haematopoetic stem cell transplant (carmustine/BCNU, Etoposide, cytarabine/Ara-C, Melphalan [BEAM] auto-haematopoetic stem cell transplant [HSCT]). METHODS: Clinical notes of patients with lymphoma who underwent either CAR-T therapy or BEAM auto-HSCT between 2018 and 2021 were reviewed. Data extracted included body weight measurements and NIS, including decreased appetite, nausea, vomiting, diarrhoea, constipation, mucositis, cytokine release syndrome (CRS) and neurotoxicity at baseline and 30 ± 7 days post-treatment. RESULTS: In total, 129 adults with lymphoma (n = 88 CAR-T vs. n = 41 BEAM) were included. Nutritional status was assessed in both groups at baseline prior to treatment. Mean absolute weight change was significantly different between groups (3.05 kg in CAR-T, -5.9 kg in BEAM, p ≤ 0.001). This was also significant when weight loss was categorised into percentage weight loss (p = 0.01). CAR-T patients experienced a significantly lower prevalence of decreased appetite (52.3% vs. 97.6%) nausea (25% vs. 78%,) vomiting (10.2% vs. 53.7%), diarrhoea (43.2% vs. 96.7%) and mucositis (5.7% vs. 75.6%) combined across all levels of severity compared to BEAM chemotherapy (all p ≤ 0.01). CRS and neurotoxicity, which are specific side effects of CAR-T therapy, were moderately positively associated with weight loss. CONCLUSIONS: Weight loss, percentage weight loss and NIS were significantly reduced in CAR-T compared to BEAM treatment. However, patients who experienced neurotoxicity during treatment did have significant weight loss.


Assuntos
Linfoma , Mucosite , Receptores de Antígenos Quiméricos , Adulto , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carmustina/efeitos adversos , Citarabina/efeitos adversos , Linfoma/tratamento farmacológico , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Náusea/induzido quimicamente , Náusea/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Receptores de Antígenos Quiméricos/uso terapêutico , Vômito/induzido quimicamente , Vômito/tratamento farmacológico , Redução de Peso , Imunoterapia Adotiva/efeitos adversos , Antígenos CD19/imunologia , Antígenos CD19/uso terapêutico
9.
bioRxiv ; 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37131765

RESUMO

Malignant astroctyoma and glioblastoma are diffuse CNS tumors that have markedly similar features, including microvascular proliferation and necrosis, and the latter presents higher grade and poorer survival. The Isocitrate dehydrogenase 1/2 (IDH) mutation further predicts improved survival and is present in oligodendroglioma and astrocytoma. The latter are more prevalent in younger populations with a median age of 37 years at diagnosis as compared to glioblastoma with a median age of 641,2. These tumors frequently have co-occurring ATRX and/or TP53 mutations (Brat et al., 2021). The IDH mutation is known to cause dysregulation of the hypoxia response broadly in CNS tumors and subsequent reduction in both tumor growth and treatment resistance. The frequency of tumor recurrence is high for diffuse CNS tumors. Understanding the mechanism and potential molecular targets enhancing treatment resistance and local invasion in IDH mutant diffuse glioma is necessary for developing new treatment strategies for better tumor control and improving overall survival. Recent evidence highlights the importance of local foci in IDH mutant glioma with an accelerated stress response as responsible for recurrence in these tumors. Here, we demonstrate that LonP1 drives NRF2 and subsequent proneural mesenchymal transition interdependent with the IDH mutation in response to stress and other tumor microenvironment cues. Our findings provide further evidence that targeting LonP1 may be a crucial strategy for improving the standard-of-care treatment in IDH mutant diffuse astrocytoma.

10.
Melanoma Res ; 33(4): 316-325, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37199712

RESUMO

Metastatic uveal melanoma (mUM) has historically been associated with short survival and limited effective treatments. Immune checkpoint inhibitors (ICIs) have been trialed in mUM; however, robust conclusions regarding their efficacy are difficult to draw given small study sizes and heterogeneous patient populations. Five databases were searched using a combination of 'ICI' and 'mUM' headings, and data on patient demographics, objective response rate (ORR), overall survival (OS) and progression-free survival (PFS) were extracted. Pooled ORR was calculated using a random effects model and the inverse variance method. Available Kaplan-Meier OS and PFS curves were used to construct summary OS and PFS plots, from which median values were derived. Pooled ORR was 9.2% overall (95% CI 7.2-11.8) [4.1% for anti-CTLA4 (95% CI 2.1-7.7), 7.1% for anti-PD(L)1 (95% CI 4.5-10.9) and 13.5% for anti-CTLA4 plus anti-PD1 (95% CI 10.0-18.0)]. Median OS was 11.5 months overall (95% CI 9.5-13.8) [8.0 months for anti-CTLA4 (95% CI 5.5-9.9), 11.7 months for anti-PD(L)1 (95% CI 9.0-14.0) and 16.0 months for ipilimumab plus anti-PD1 (95% CI 11.5-17.7) ( P < 0.001)]. Median PFS was 3.0 months overall (95% CI 2.9-3.1). ICIs have limited efficacy in mUM and a recommendation for their use must consider the balance of benefit and risk for individual patients if no other options are available. Further biomarker profiling studies may be helpful in assessing which patients will benefit from ICIs, in particular the addition of ipilimumab to anti-PD1 therapy.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/patologia , Ipilimumab/farmacologia , Ipilimumab/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico
11.
Curr Oncol Rep ; 25(6): 609-621, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36988735

RESUMO

PURPOSE OF REVIEW: In the preceding decade, the management of metastatic cutaneous melanoma has been revolutionised with the development of highly effective therapies including immune checkpoint inhibitors (specifically CTLA-4 and PD-1 inhibitors) and targeted therapies (BRAF and MEK inhibitors). The role of chemotherapy in the contemporary management of melanoma is undefined. RECENT FINDINGS: Extended analyses highlight substantially improved 5-year survival rates of approximately 50% in patients with metastatic melanoma treated with first-line therapies. However, most patients will progress on these first-line treatments. Sequencing of chemotherapy following failure of targeted and immunotherapies is associated with low objective response rates and short progression-free survival, and thus, meaningful benefits to patients are minimal. Chemotherapy has limited utility in the contemporary management of cutaneous melanoma (with a few exceptions, discussed herein) and should not be the standard treatment sequence following failure of first-line therapies. Instead, enrolment onto clinical trials should be standard-of-care in these patients.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/patologia , Neoplasias Cutâneas/patologia , Terapia de Alvo Molecular , Imunoterapia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/uso terapêutico , Melanoma Maligno Cutâneo
12.
Int J Rheum Dis ; 26(6): 1167-1171, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36798005

RESUMO

INTRODUCTION: Rheumatoid arthritis (RA) may predispose patients to opportunistic infections-either from innate immune dysregulation, or as a result of immunosuppressant use to treat the RA. Particularly concerning opportunistic infections are those caused by non-tuberculous mycobacterial (NTM) organisms, the incidence of which has been increasing in epidemiological studies. Despite this, guidelines on the management of patients with RA who develop NTM infections are scarce, particularly with respect to immunosuppressant regimen modulation and duration of antibiotic therapy. CASE REPORT: Herein, we present a case of disseminated Mycobacterium chelonae infection, manifesting as arthralgia and cutaneous nodules. DISCUSSION: In addition, a review of the literature was conducted to Preferred Reporting Items for Systemic Reviews and Meta-Analyses guidelines to identify similar cases in the literature-revealing that all RA-associated M. Chelonae infections occurred in immunosuppressed patients (the majority with corticosteroids or tumor necrosis factor inhibitors), and considerable heterogeneity in management approaches. Further research regarding risk factors, preventative approaches and best management of such NTM infections in vulnerable patients with RA is required in order to establish consensus guidelines and consistency.


Assuntos
Artrite Reumatoide , Infecções por Mycobacterium não Tuberculosas , Mycobacterium chelonae , Infecções Oportunistas , Humanos , Artrite Reumatoide/complicações , Infecções por Mycobacterium não Tuberculosas/complicações , Infecções por Mycobacterium não Tuberculosas/microbiologia , Imunossupressores/efeitos adversos
15.
J Am Acad Dermatol ; 87(3): 605-613, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34715287

RESUMO

V-raf murine sarcoma viral oncogene homolog B1 (BRAF) inhibitors have emerged as a promising targeted therapy for malignancies with BRAF mutations, particularly metastatic melanoma. However, granulomatous reactions (GRs), including sarcoidosis and sarcoid-like reactions, have been reported as a consequence of BRAF inhibition. It is important to adequately characterize these GRs, including cutaneous manifestations and systemic involvement, in order to guide investigations and management. A literature review was conducted to characterize the spectrum of GRs associated with BRAF inhibitors, identifying 55 reactions affecting 51 patients, with 37 reactions limited to cutaneous involvement. Further, a possible correlation with cancer response, mechanisms of granuloma formation, and a proposed workup and management approach for these GRs are presented.


Assuntos
Melanoma , Neoplasias Cutâneas , Animais , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Camundongos , Mutação , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética
16.
Biochem J ; 458(3): 513-23, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24428730

RESUMO

Plasmodium parasites possess two endosymbiotic organelles: a mitochondrion and a relict plastid called the apicoplast. To accommodate the translational requirements of these organelles in addition to its cytosolic translation apparatus, the parasite must maintain a supply of charged tRNA molecules in each of these compartments. In the present study we investigate how the parasite manages these translational requirements for charged tRNACys with only a single gene for CysRS (cysteinyl-tRNA synthetase). We demonstrate that the single PfCysRS (Plasmodium falciparum CysRS) transcript is alternatively spliced, and, using a combination of endogenous and heterologous tagging experiments in both P. falciparum and Toxoplasma gondii, we show that CysRS isoforms traffic to the cytosol and apicoplast. PfCysRS can recognize and charge the eukaryotic tRNACys encoded by the Plasmodium nucleus as well as the bacterial-type tRNA encoded by the apicoplast genome, albeit with a preference for the eukaryotic type cytosolic tRNA. The results of the present study indicate that apicomplexan parasites have lost their original plastidic cysteinyl-tRNA synthetase, and have replaced it with a dual-targeted eukaryotic type CysRS that recognizes plastid and nuclear tRNACys. Inhibitors of the Plasmodium dual-targeted CysRS would potentially offer a therapy capable of the desirable immediate effects on parasite growth as well as the irreversibility of inhibitors that disrupt apicoplast inheritance.


Assuntos
Aminoacil-tRNA Sintetases/metabolismo , Citosol/metabolismo , Plasmodium falciparum/enzimologia , Processamento Alternativo , Aminoacil-tRNA Sintetases/genética , Apicoplastos/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , Mutação , Plasmodium falciparum/genética , Transporte Proteico , Temperatura , Toxoplasma/genética
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