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1.
Cell ; 180(5): 895-914.e27, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-32142680

RESUMEN

A safe and controlled manipulation of endocytosis in vivo may have disruptive therapeutic potential. Here, we demonstrate that the anti-emetic/anti-psychotic prochlorperazine can be repurposed to reversibly inhibit the in vivo endocytosis of membrane proteins targeted by therapeutic monoclonal antibodies, as directly demonstrated by our human tumor ex vivo assay. Temporary endocytosis inhibition results in enhanced target availability and improved efficiency of natural killer cell-mediated antibody-dependent cellular cytotoxicity (ADCC), a mediator of clinical responses induced by IgG1 antibodies, demonstrated here for cetuximab, trastuzumab, and avelumab. Extensive analysis of downstream signaling pathways ruled out on-target toxicities. By overcoming the heterogeneity of drug target availability that frequently characterizes poorly responsive or resistant tumors, clinical application of reversible endocytosis inhibition may considerably improve the clinical benefit of ADCC-mediating therapeutic antibodies.


Asunto(s)
Citotoxicidad Celular Dependiente de Anticuerpos/efectos de los fármacos , Resistencia a Antineoplásicos/inmunología , Neoplasias/tratamiento farmacológico , Proclorperazina/farmacología , Animales , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales Humanizados/farmacología , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Presentación de Antígeno/efectos de los fármacos , Biopsia , Cetuximab/farmacología , Sistemas de Liberación de Medicamentos/métodos , Resistencia a Antineoplásicos/genética , Endocitosis/efectos de los fármacos , Endocitosis/inmunología , Xenoinjertos , Humanos , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Células MCF-7 , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Ratones , Neoplasias/genética , Neoplasias/inmunología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Trastuzumab/farmacología
2.
PLoS Pathog ; 18(1): e1010166, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35007292

RESUMEN

A hallmark of Listeria (L.) monocytogenes pathogenesis is bacterial escape from maturing entry vacuoles, which is required for rapid bacterial replication in the host cell cytoplasm and cell-to-cell spread. The bacterial transcriptional activator PrfA controls expression of key virulence factors that enable exploitation of this intracellular niche. The transcriptional activity of PrfA within infected host cells is controlled by allosteric coactivation. Inhibitory occupation of the coactivator site has been shown to impair PrfA functions, but consequences of PrfA inhibition for L. monocytogenes infection and pathogenesis are unknown. Here we report the crystal structure of PrfA with a small molecule inhibitor occupying the coactivator site at 2.0 Å resolution. Using molecular imaging and infection studies in macrophages, we demonstrate that PrfA inhibition prevents the vacuolar escape of L. monocytogenes and enables extensive bacterial replication inside spacious vacuoles. In contrast to previously described spacious Listeria-containing vacuoles, which have been implicated in supporting chronic infection, PrfA inhibition facilitated progressive clearance of intracellular L. monocytogenes from spacious vacuoles through lysosomal degradation. Thus, inhibitory occupation of the PrfA coactivator site facilitates formation of a transient intravacuolar L. monocytogenes replication niche that licenses macrophages to effectively eliminate intracellular bacteria. Our findings encourage further exploration of PrfA as a potential target for antimicrobials and highlight that intra-vacuolar residence of L. monocytogenes in macrophages is not inevitably tied to bacterial persistence.


Asunto(s)
Listeria monocytogenes/patogenicidad , Listeriosis/microbiología , Macrófagos/microbiología , Vacuolas/microbiología , Virulencia/fisiología , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL
3.
Curr Treat Options Oncol ; 25(3): 275-283, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38270799

RESUMEN

OPINION STATEMENT: Monoclonal antibody (mAb) therapy is now considered a main component of cancer therapy in Australia. Although traditionally thought of as pure signalling inhibitors, a large proponent of these medications function through antibody-dependent cell-mediated cytotoxicity (ADCC). Currently, most protocols and institutional guidelines for ADCC-mediated mAbs promote the use of corticosteroids as premedication: this is implemented to reduce infusion-related reactions (IRRs) and antiemesis prophylaxis and combat concurrently administered chemotherapy-related syndromes. Concerningly, the inhibitory effects of ADCC by corticosteroids are well documented; henceforth, it is possible the current standard of care is misaligned to the literature surrounding ADCC. Subsequently, clinicians' decisions to act in contrast to this literature may be reducing the efficacy of mAbs. The literature suggests that the redundant use of corticosteroids should be cautioned against when used in conjunction with ADCC-mediated mAbs-this is due to the consequent reduction in anti-tumour activity. Owing to the fact IRRs typically occur upon initial infusion, the authors advocate for individual clinicians and institutional protocols to considering augmenting their practice to corticosteroid premedication at the first dose only, unless clinically indicated. Additionally, product information (PI) and consumer medicine information (CMI) documents distributed by Australian and international regulatory agencies should consider disclosing the risk of concurrent steroids with these medications. Moreover, the authors suggest considering alternative medications for the management of side effects.


Asunto(s)
Anticuerpos Monoclonales , Esteroides , Humanos , Línea Celular Tumoral , Australia , Anticuerpos Monoclonales/efectos adversos , Premedicación , Corticoesteroides
4.
Nanomedicine ; 56: 102733, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38199450

RESUMEN

Anti-cancer monoclonal antibodies often fail to provide therapeutic benefit in receptor-positive patients due to rapid endocytosis of antibody-bound cell surface receptors. High dose co-administration of prochlorperazine (PCZ) inhibits endocytosis and sensitises tumours to mAbs by inhibiting dynamin II but can also introduce neurological side effects. We examined the potential to use PEGylated liposomal formulations of PCZ (LPCZ) to retain the anti-cancer effects of PCZ, but limit brain uptake. Uncharged liposomes showed complete drug encapsulation and pH-dependent drug release, but cationic liposomes showed limited drug encapsulation and lacked pH-dependent drug release. Uncharged LPCZ showed comparable inhibition of EGFR internalisation to free PCZ in KJD cells. After IV administration to rats, LPCZ reduced the plasma clearance and brain uptake of PCZ compared to IV PCZ. The results suggest that LPCZ may offer some benefit over PCZ as an adjunct therapy in cancer patients receiving mAb treatment.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Ratas , Animales , Proclorperazina/efectos adversos , Dinamina II/metabolismo , Liposomas/uso terapéutico , Neoplasias/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales/metabolismo , Encéfalo/metabolismo , Polietilenglicoles/uso terapéutico
5.
Hum Mol Genet ; 30(24): 2393-2401, 2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34274969

RESUMEN

Lung cancer is the commonest cause of cancer deaths worldwide. Although strongly associated with smoking, predisposition to lung cancer is also heritable, with multiple common risk variants identified. Rarely, dominantly inherited non-small-cell lung cancer (NSCLC) has been reported due to somatic mutations in EGFR/ErbB1 and ERBB2. Germline exome sequencing was performed in a multi-generation family with autosomal dominant NSCLC, including an affected child. Tumour samples were also sequenced. Full-length wild-type (wtErbB3) and mutant ERBB3 (mutErbB3) constructs were transfected into HeLa cells. Protein expression, stability, and subcellular localization were assessed, and cellular proliferation, pAkt/Akt and pERK levels determined. A novel germline variant in ERBB3 (c.1946 T > G: p.Iso649Arg), coding for receptor tyrosine-protein kinase erbB-3 (ErbB3), was identified, with appropriate segregation. There was no loss-of-heterozygosity in tumour samples. Both wtErbB3 and mutErbB3 were stably expressed. MutErbB3-transfected cells demonstrated an increased ratio of the 80 kDa form (which enhances proliferation) compared with the full-length (180 kDa) form. MutErbB3 and wtErbB3 had similar punctate cytoplasmic localization pre- and post-epidermal growth factor stimulation; however, epidermal growth factor receptor (EGFR) levels decreased faster post-stimulation in mutErbB3-transfected cells, suggesting more rapid processing of the mutErbB3/EGFR heterodimer. Cellular proliferation was increased in mutErbB3-transfected cells compared with wtErbB3 transfection. MutErbB3-transfected cells also showed decreased pAkt/tAkt ratios and increased pERK/tERK 30 min post-stimulation compared with wtErbB3 transfection, demonstrating altered signalling pathway activation. Cumulatively, these results support this mutation as tumorogenic. This is the first reported family with a germline ERBB3 mutation causing heritable NSCLC, furthering understanding of the ErbB family pathway in oncogenesis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinogénesis/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Niño , Células Germinativas/metabolismo , Mutación de Línea Germinal , Células HeLa , Humanos , Neoplasias Pulmonares/genética , Receptor ErbB-2/genética , Receptor ErbB-3/genética
6.
Mol Pharm ; 20(9): 4468-4477, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37548597

RESUMEN

Dynamin II (dynII) plays a significant role in the internalization pathways of endocytic cells, by allowing membrane invaginations to "bud off". An important class of dynII inhibitors that are used clinically are phenothiazines, such as prochlorperazine (PCZ). PCZ is an antipsychotic drug but is also currently in clinical trials at higher concentrations as an adjuvant in cancer patients that increases the efficacy of monoclonal antibodies at high intravenous doses. It is unknown, however, whether high-dose dynII inhibitors have the potential to alter the pharmacokinetics of co-administered chemotherapeutic nanomedicines that are largely cleared via the mononuclear phagocyte system. This work therefore sought to investigate the impact of clinically relevant concentrations of phenothiazines, PCZ and thioridazine, on in vitro liposome endocytosis and in vivo liposome pharmacokinetics after PCZ infusion in rats. The uptake of fluorescently labeled PEGylated liposomes into differentiated and undifferentiated THP-1 and RAW246.7 cells, and primary human peripheral white blood cells, was investigated via flow cytometry after co-incubation with dynII inhibitors. The IV pharmacokinetics of PEGylated liposomes were also investigated in rats after a 20 min infusion with PCZ. Phenothiazines and dyngo4a reduced the uptake of PEGylated liposomes by THP-1 and RAW264.7 cells in a concentration-dependent manner in vitro. However, dynII inhibitors did not alter the mean uptake of liposomes by human peripheral white blood cells, but endocytic white cells from some donors exhibited sensitivity to phenothiazine exposure. When a clinically relevant dose of PCZ was co-administered with PEGylated liposomal doxorubicin (Caelyx/Doxil) in rats, the pharmacokinetics and biodistribution of liposomes were unaltered. These data suggest that while clinically relevant doses of dynII inhibitors can inhibit the uptake of liposomes by endocytic cells in vitro, they are unlikely to significantly affect the pharmacokinetics of long-circulating, co-administered liposomes.


Asunto(s)
Dinamina II , Liposomas , Ratas , Humanos , Animales , Distribución Tisular , Doxorrubicina , Polietilenglicoles , Fenotiazinas , Proclorperazina
7.
Cells Tissues Organs ; 211(4): 506-526, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34380144

RESUMEN

Corneal blindness accounts for 5.1% of visual deficiency and is the fourth leading cause of blindness globally. An additional 1.5-2 million people develop corneal blindness each year, including many children born with or who later develop corneal infections. Over 90% of corneal blind people globally live in low- and middle-income regions (LMIRs), where corneal ulcers are approximately 10-fold higher compared to high-income countries. While corneal transplantation is an effective option for patients in high-income countries, there is a considerable global shortage of corneal graft tissue and limited corneal transplant programs in many LMIRs. In situ tissue regeneration aims to restore diseases or damaged tissues by inducing organ regeneration. This can be achieved in the cornea using biomaterials based on extracellular matrix (ECM) components like collagen, hyaluronic acid, and silk. Solid corneal implants based on recombinant human collagen type III were successfully implanted into patients resulting in regeneration of the corneal epithelium, stroma, and sub-basal nerve plexus. As ECM crosslinking and manufacturing methods improve, the focus of biomaterial development has shifted to injectable, in situ gelling formulations. Collagen, collagen-mimetic, and gelatin-based in situ gelling formulas have shown the ability to repair corneal wounds, surgical incisions, and perforations in in-vivo models. Biomaterial approaches may not be sufficient to treat inflammatory conditions, so other cell-free therapies such as treatment with tolerogenic exosomes and extracellular vesicles may improve treatment outcomes. Overall, many of the technologies described here show promise as future medical devices or combination products with cell or drug-based therapies. In situ tissue regeneration, particularly with liquid formulas, offers the ability to triage and treat corneal injuries and disease with a single regenerative solution, providing alternatives to organ transplantation and improving patient outcomes.


Asunto(s)
Córnea , Trasplante de Córnea , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/uso terapéutico , Ceguera , Niño , Colágeno/farmacología , Córnea/fisiología , Humanos
8.
Int J Cancer ; 146(8): 2305-2314, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-31950498

RESUMEN

Now is an exciting era of development in immunotherapy checkpoint inhibitors and their effect on the treatment of NPC. While the general prognosis of R/M disease is poor, immunotherapy offers some promise in a malignancy associated with EBV and characterized by a peritumoural immune infiltrate. Our study aims to review past and on-going clinical trials of monoclonal antibody therapies against the checkpoint inhibitors (e.g. PD1 and CTLA-4), in R/M NPC. All randomized and nonrandomized controlled trials involving immune checkpoint inhibitor interventions for treatment of NPC were included in the study. We utilized a validated "risk of bias" tool to assess study quality. Four separate Phase I-II trials report the potential of PD1 inhibitor treatment for patients with NPC. Within the observed groups, camrelizumab combined with chemotherapy achieved an objective response in 91% of patients as first-line treatment for metastatic NPC (PFS 68% at 1-year) but this was associated with a high rate of grade >3 adverse events (87%; CTCAE version 4.03). The remaining three studies focused on recurrent NPC disease in patients who had received at least one line of prior chemotherapy. Within this group, camrelizumab monotherapy achieved an objective response in 34% of patients (PFS 27% at 1-year; range across all three studies 20.5-34%). No NPC trial has yet reported on specific outcomes for non-PD1 checkpoint inhibitors but 11 on-going studies include alternative targets (e.g. PD-L1/CTLA-4) as combination or monotherapy treatments. In considering checkpoint immunotherapies for NPC, initial results show promise for anti-PD1 interventions. Further phase I-III trials are in progress to clarify clinical outcomes, fully determine safety profiles, and optimize drug combinations and administration schedules.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Antígeno CTLA-4/antagonistas & inhibidores , Carcinoma Nasofaríngeo/tratamiento farmacológico , Neoplasias Nasofaríngeas/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Antígeno B7-H1/inmunología , Antígeno CTLA-4/inmunología , Quimioradioterapia , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Humanos , Carcinoma Nasofaríngeo/inmunología , Neoplasias Nasofaríngeas/inmunología , Nivolumab/administración & dosificación , Nivolumab/uso terapéutico , Receptor de Muerte Celular Programada 1/inmunología
9.
Br J Clin Pharmacol ; 86(9): 1711-1725, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32372470

RESUMEN

The discovery of immune checkpoints and their role in modulating immune response have revolutionised cancer treatment in recent years. The immune checkpoints, cytotoxic T-lymphocyte-associated protein 4, programmed cell death protein 1 and its ligand, programmed cell death-ligand 1, have been extensively studied. Currently 7 monoclonal antibodies targeting these immune checkpoints are approved for treatment of various cancers. Inhibiting immune checkpoints has shown some success in clinic, however, a proportion of patients do not benefit from this treatment. Several other inhibitory molecules, in addition to lymphocyte-associated protein 4 and programmed cell death protein 1, are known to be involved in regulating immune response. To further improve patient outcomes, studies have examined targeting these inhibitory molecules through combination therapies. This review discusses the current landscape of combination therapies of checkpoint inhibitors.


Asunto(s)
Antineoplásicos Inmunológicos , Neoplasias , Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Terapia Combinada , Humanos , Inmunoterapia , Neoplasias/tratamiento farmacológico
10.
Pharm Res ; 37(11): 224, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33078255

RESUMEN

PURPOSE: The aim of this work was to identify whether biochemical and physiological sources of mAb pharmacokinetic sex-effects could be identified in the rat model where target-mediated disposition is avoided. METHODS: Plasma and lymphatic pharmacokinetics of the humanised anti-EGFR antibody cetuximab, along with potential physiological and biochemical drivers of pharmacokinetic sex differences, were examined in male and female rats. Cetuximab was used as a model mAb since plasma clearance is slower in female patients. RESULTS: When plasma concentrations were normalised to dose, female rats displayed slower plasma clearance than males, but no significant differences were observed in liver and spleen biodistribution. Sex differences in apparent plasma clearance, however, were abolished after normalisation to body weight, surface area or fat-free mass. Significant sex differences were observed in plasma testosterone, endogenous IgG and fat free mass, but did not correlate with apparent clearance. Females did, however, show two-fold higher lymphatic exposure compared to males. CONCLUSIONS: These data suggested that mAbs more efficiently access lymph in females, but this does not affect plasma pharmacokinetics or biodistribution. Further, the data suggest that sex differences observed in humans could be a function of antigen density.


Asunto(s)
Antineoplásicos Inmunológicos/farmacocinética , Cetuximab/farmacocinética , Sistema Linfático/metabolismo , Administración Intravenosa , Animales , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/sangre , Cetuximab/administración & dosificación , Cetuximab/sangre , Femenino , Masculino , Tasa de Depuración Metabólica , Ratas Sprague-Dawley , Factores Sexuales , Distribución Tisular
11.
Curr Treat Options Oncol ; 21(1): 9, 2020 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-32016630

RESUMEN

OPINION STATEMENT: Recent studies have evidenced the potential of combining anti-EGFR therapies with anti-PD-1/PD-L1 checkpoint therapies. Both anti-EGFR and anti-PD-1/PD-L1 have been separately tested in the treatment of cutaneous SCC (cSCC). Here, we review recent data on EGFR in the context of cancer progression, as a prognostic and as a therapeutic target in cSCC. Anti-EGFR/checkpoint immunotherapy and other combination therapy approaches are discussed. With the advent of immunotherapy, EGFR is still a valid cSCC target.


Asunto(s)
Biomarcadores de Tumor , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/metabolismo , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/metabolismo , Antineoplásicos Inmunológicos/farmacología , Antineoplásicos Inmunológicos/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Ensayos Clínicos como Asunto , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Proteínas de Punto de Control Inmunitario/genética , Proteínas de Punto de Control Inmunitario/metabolismo , Inmunoterapia , Terapia Molecular Dirigida , Pronóstico , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Resultado del Tratamiento
12.
Traffic ; 16(6): 635-54, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25693808

RESUMEN

Chlorpromazine is a phenothiazine-derived antipsychotic drug (APD) that inhibits clathrin-mediated endocytosis (CME) in cells by an unknown mechanism. We examined whether its action and that of other APDs might be mediated by the GTPase activity of dynamin. Eight of eight phenothiazine-derived APDs inhibited dynamin I (dynI) in the 2-12 µm range, the most potent being trifluoperazine (IC50 2.6 ± 0.7 µm). They also inhibited dynamin II (dynII) at similar concentrations. Typical and atypical APDs not based on the phenothiazine scaffold were 8- to 10-fold less potent (haloperidol and clozapine) or were inactive (droperidol, olanzapine and risperidone). Kinetic analysis showed that phenothiazine-derived APDs were lipid competitive, while haloperidol was uncompetitive with lipid. Accordingly, phenothiazine-derived APDs inhibited dynI GTPase activity stimulated by lipids but not by various SH3 domains. All dynamin-active APDs also inhibited transferrin (Tfn) CME in cells at related potencies. Structure-activity relationships (SAR) revealed dynamin inhibition to be conferred by a substituent group containing a terminal tertiary amino group at the N2 position. Chlorpromazine was previously proposed to target AP-2 recruitment in the formation of clathrin-coated vesicles (CCV). However, neither chlorpromazine nor thioridazine affected AP-2 interaction with amphiphysin or clathrin. Super-resolution microscopy revealed that chlorpromazine blocks neither clathrin recruitment by AP-2, nor AP-2 recruitment, showing that CME inhibition occurs downstream of CCV formation. Overall, potent dynamin inhibition is a shared characteristic of phenothiazine-derived APDs, but not other typical or atypical APDs, and the data indicate that dynamin is their likely in-cell target in endocytosis.


Asunto(s)
Antipsicóticos/farmacología , Clatrina/metabolismo , Dinaminas/metabolismo , Endocitosis/efectos de los fármacos , Fenotiazinas/farmacología , Línea Celular Tumoral , Vesículas Cubiertas por Clatrina/metabolismo , Humanos , Transferrina/metabolismo
13.
Int J Cancer ; 138(2): 281-92, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25612559

RESUMEN

Patients receiving immunosuppression to prevent organ transplant rejection are at a greatly increased risk of developing nonmelanoma skin cancer. In recent years a correlation has been identified between the class of immunosuppressant that these patients receive and their subsequent cancer risk; in particular, patients switched from calcineurin inhibitors to mammalian target of rapamycin (mTOR) inhibitors not only displayed a dramatic reduction in new tumor formation but also in some cases a regression of their existing lesions. Studies of cancer models in mice and cell lines in the laboratory have attributed these discrepancies in cancer risk to the ability of immunosuppressants such as mTOR inhibitors to elicit direct anticancer effects, including suppressing angiogenesis and increasing autophagy-mediated DNA repair. Recent evidence from the immunological literature however, suggests a significant alternative contribution of mTOR inhibitors; namely the promotion of memory T-cell function. Recent advances in understanding memory T-cell establishment and the demonstration of their critical role in long-term immunity make it timely to review the available evidence as to whether the improved nonmelanoma skin cancer outcome shown by patients switched to mTOR inhibitor treatment regimens may be associated with the retainment of memory T-cell function.


Asunto(s)
Huésped Inmunocomprometido/inmunología , Inmunosupresores/efectos adversos , Trasplante de Órganos/efectos adversos , Neoplasias Cutáneas/inmunología , Linfocitos T/efectos de los fármacos , Animales , Humanos , Factores de Riesgo , Linfocitos T/inmunología , Receptores de Trasplantes
14.
Cancer Cell Int ; 16: 24, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27034617

RESUMEN

BACKGROUND: Understanding the cause of therapeutic resistance and identifying new biomarkers in breast cancer to predict therapeutic responses will help optimise patient care. Calcium (Ca(2+))-signalling is important in a variety of processes associated with tumour progression, including breast cancer cell migration and proliferation. Ca(2+)-signalling is also linked to the acquisition of multidrug resistance. This study aimed to assess the expression level of proteins involved in Ca(2+)-signalling in an in vitro model of trastuzumab-resistance and to assess the ability of identified targets to reverse resistance and/or act as potential biomarkers for prognosis or therapy outcome. METHODS: Expression levels of a panel of Ca(2+)-pumps, channels and channel regulators were assessed using RT-qPCR in resistant and sensitive age-matched SKBR3 breast cancer cells, established through continuous culture in the absence or presence of trastuzumab. The role of Cav3.2 in the acquisition of trastuzumab-resistance was assessed through pharmacological inhibition and induced overexpression. Levels of Cav3.2 were assessed in a panel of non-malignant and malignant breast cell lines using RT-qPCR and in patient samples representing different molecular subtypes (PAM50 cohort). Patient survival was also assessed in samples stratified by Cav3.2 expression (METABRIC and KM-Plotter cohort). RESULTS: Increased mRNA of Cav3.2 was a feature of both acquired and intrinsic trastuzumab-resistant SKBR3 cells. However, pharmacological inhibition of Cav3.2 did not restore trastuzumab-sensitivity nor did Cav3.2 overexpression induce the expression of markers associated with resistance, suggesting that Cav3.2 is not a driver of trastuzumab-resistance. Cav3.2 levels were significantly higher in luminal A, luminal B and HER2-enriched subtypes compared to the basal subtype. High levels of Cav3.2 were associated with poor outcome in patients with oestrogen receptor positive (ER+) breast cancers, whereas Cav3.2 levels were correlated positively with patient survival after chemotherapy in patients with HER2-positive breast cancers. CONCLUSION: Our study identified elevated levels of Cav3.2 in trastuzumab-resistant SKBR3 cell lines. Although not a regulator of trastuzumab-resistance in HER2-positive breast cancer cells, Cav3.2 may be a potential differential biomarker for survival and treatment response in specific breast cancer subtypes. These studies add to the complex and diverse role of Ca(2+)-signalling in breast cancer progression and treatment.

15.
Curr Opin Crit Care ; 22(4): 303-7, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27258666

RESUMEN

PURPOSE OF REVIEW: The purpose of this review is to highlight emerging techniques used to determine body composition early in ICU stay, their prediction of poor outcome, and what is required before they can be more widely used. RECENT FINDINGS: Opportunistic use of imaging techniques to assess muscle mass shows promise with regard to predicting patient outcomes; however, some of these techniques are expensive. Mid-arm muscle circumference and physical assessments of muscle wasting and subcutaneous fat loss using the subjective global assessment (SGA) are simple cheap tools that can be undertaken at the ICU patient bedside. Furthermore, each of these simple measures is a better predictor of patient outcome than BMI. SUMMARY: Mid-arm muscle circumference, SGA fat loss, and SGA muscle wasting have each been found to be better predictors of poor outcome than BMI in ICU patients.Mid-arm muscle circumference, SGA fat loss, and SGA muscle wasting may be able to identify patients who are most likely to benefit from enhanced nutrition support.We need further research incorporating the use of these simple measures to evaluate their ability to accurately identify patients most likely to benefit from enhanced nutritional support.


Asunto(s)
Enfermedad Crítica/terapia , Evaluación Nutricional , Estado Nutricional , Evaluación del Resultado de la Atención al Paciente , Examen Físico/instrumentación , Composición Corporal , Índice de Masa Corporal , Humanos , Desnutrición
16.
Dermatology ; 228(3): 207-10, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24686315

RESUMEN

BACKGROUND: The variability in susceptibility to onychomycosis for individuals exposed to the same environmental risk factors raises the possibility that there may be individuals with a genetic predisposition to dermatophyte infection. OBJECTIVE: To determine whether there are genetic mutations or genotypes which contribute to onychomycosis. METHODS: The PubMed database was searched for examples of immune deficiencies resulting in dermatophyte infections. RESULTS: There are mutations in the innate immune receptors Dectin-1 and its adaptor protein CARD9 which result in familial mucocutaneous infections. There are also specific human leukocyte antigen genotypes that are more common in individuals and families with a high prevalence of onychomycosis. In addition, some patients have been reported with insufficient levels of CD4+CD25+ regulatory T cells. These deficits impair a full innate and adaptive immune response and may result in chronic or recurrent infections. CONCLUSIONS: There are documented mutations and genotypes that contribute to familial and individual susceptibility to onychomycosis.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD/genética , Predisposición Genética a la Enfermedad/epidemiología , Lectinas Tipo C/genética , Mutación , Onicomicosis/genética , Inmunidad Adaptativa , Bases de Datos Factuales , Femenino , Genotipo , Humanos , Inmunidad Innata/fisiología , Incidencia , Masculino , Onicomicosis/epidemiología , Onicomicosis/inmunología , Pronóstico
17.
Australas J Dermatol ; 55(1): 24-34, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23425099

RESUMEN

Squamous cell carcinoma (SCC) of the skin is an increasingly common diagnosis worldwide. Together with precursor lesions, SCC carry a significant morbidity, particularly in regions with high solar UV radiation levels. Advanced lesions are locally or sometimes widely metastatic and may be resistant to treatment. Drugs targeting the epidermal growth factor receptor (EGFR) are currently the only significant non-surgical option for advanced SCC beyond radiotherapy and conventional chemotherapy. The role of the EGFR in skin cancer is described and the outcomes of targeted anti-EGFR therapy published to date are summarised. The future of anti-EGFR targeted therapies in the treatment of skin cancer is discussed. Targeted molecular therapies are becoming increasingly widespread and an understanding of the evidence for their use as well as their side effect profile is important in order to offer patients informed and current advice.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Receptores ErbB/antagonistas & inhibidores , Neoplasias Cutáneas/tratamiento farmacológico , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Carcinoma de Células Escamosas/química , Cetuximab , Clorhidrato de Erlotinib , Gefitinib , Humanos , Terapia Molecular Dirigida , Panitumumab , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Quinazolinas/uso terapéutico , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas/química
18.
Skin Therapy Lett ; 19(1): 1-4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24570290

RESUMEN

Efinaconazole is an emerging antifungal therapy for the topical treatment of onychomycosis. Efinaconazole is an inhibitor of sterol 14α-demethylase and is more effective in vitro than terbinafine, itraconazole, ciclopirox and amorolfine against dermatophytes, yeasts and non-dermatophyte molds. Phase II studies indicate that efinaconazole 10% nail solution is more effective than either the 5% strength or 10% solution with semi-occlusion. In duplicate Phase III clinical trials, complete cure rates of 17.8% and 15.2% were demonstrated. The mean mycological cure rate for efinaconazole is similar to the oral antifungal itraconazole and exceeds the efficacy of topical ciclopirox. Efinaconazole showed minimal localized adverse events, which ceased upon stopping treatment. Overall, efinaconazole 10% nail solution is an effective topical monotherapy for distal and lateral subungual onychomycosis (<65% nail involvement, excluding the matrix) that shows further potential use as an adjunct to oral and device-based therapies.


Asunto(s)
Antifúngicos/uso terapéutico , Onicomicosis/tratamiento farmacológico , Triazoles/uso terapéutico , Ensayos Clínicos como Asunto , Humanos , Pruebas de Sensibilidad Microbiana , Triazoles/efectos adversos , Triazoles/farmacología
19.
Aust J Prim Health ; 20(3): 285-90, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23711080

RESUMEN

Few epidemiological studies of middle ear disease have been conducted in Aboriginal and Torres Strait Islander populations, yet the disease is common and causes hearing impairment and poorer educational outcomes. The objective of this study is to identify factors associated with abnormal middle ear appearance, a proxy for middle ear disease. Aboriginal and Torres Strait Islander children aged 0-14 years receiving a Child Health Check (CHC) at an urban Indigenous Health Service, Brisbane, Australia were recruited from 2007 to 2010. Mixed-effects models were used to explore associations of 10 recognised risk factors with abnormal middle ear appearance at the time of the CHC. Ethical approval and community support for the project were obtained. Four hundred and fifty-three children were included and 54% were male. Participants were Aboriginal (92%), Torres Strait Islander (2%) or both (6%). Abnormal middle ear appearance was observed in 26 (6%) children and was significantly associated with previous ear infection (odds ratio (OR), 8.8; 95% confidence interval (CI), 3.2-24.0) and households with eight or more people (OR, 3.8; 95% CI, 1.1-14.1) in the imputed multivariable mixed-effects model. No significant associations were found for the other recognised risk factors investigated. Overcrowding should continue to be a core focus for communities and policy makers in reducing middle ear disease and its consequences in Aboriginal and Torres Strait Islander peoples.


Asunto(s)
Enfermedades del Oído/epidemiología , Composición Familiar , Servicios de Salud del Indígena/estadística & datos numéricos , Nativos de Hawái y Otras Islas del Pacífico/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Adolescente , Distribución por Edad , Australia/epidemiología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Oportunidad Relativa , Factores de Riesgo , Distribución por Sexo
20.
EBioMedicine ; 104: 105176, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38810560

RESUMEN

BACKGROUND: Natural killer (NK) cells are important innate immunity players and have unique abilities to recognize and eliminate cancer cells, particularly in settings of antibody-opsonization and antibody-dependant cellular cytotoxicity (ADCC). However, NK cell-based responses in bladder cancers to therapeutic antibodies are typically immunosuppressed, and these immunosuppressive mechanisms are largely unknown. METHODS: Single cell RNA sequencing (scRNA-seq) and high-dimensional flow cytometry were used to investigate the phenotype of tumour-infiltrating NK cells in patients with bladder cancer. Further, in vitro, and in vivo models of this disease were used to validate these findings. FINDINGS: NK cells within bladder tumours displayed reduced expression of FcγRIIIa/CD16, the critical Fc receptor involved in ADCC-mediated cytotoxicity, on both transcriptional and protein levels. Transcriptional signatures of transforming growth factor (TGF)-ß-signalling, a pleiotropic cytokine known for its immunosuppressive and tissue residency-inducing effects, were upregulated in tumour-infiltrating NK cells. TGF-ß mediated CD16 downregulation on NK cells, was further validated in vitro, which was accompanied by a transition into a tissue residency phenotype. This CD16 downregulation was also abrogated by TGF-ßR signalling inhibition, which could also restore the ADCC ability of NK cells subject to TGF-ß effects. In a humanized mouse model of bladder cancer, mice treated with a TGF-ß inhibitor exhibited increased ADCC activity compared to mice treated only with antibodies. INTERPRETATION: This study highlights how TGF-ß-rich bladder cancers inhibit NK cell-mediated ADCC by downregulating CD16. TGF-ß inhibition represents new avenues to reverse immunosuppression and enhance the tumoricidal capacity of NK cells in bladder cancer. FUNDING: The Guimaraes Laboratory is funded by a US Department of Defense-Breast Cancer Research Program-Breakthrough Award Level 1 (#BC200025), a grant (#2019485) awarded through the Medical Research Future Fund (MRFF, with the support of the Queensland Children's Hospital Foundation, Microba Life Sciences, Richie's Rainbow Foundation, Translational Research Institute (TRI) and UQ), and a grant (#RSS_2023_085) funded by a Metro South Health Research Support Scheme. J.K.M.W. is funded by a UQ Research Training Program PhD Scholarship and N.O. is funded by a NHMRC Postgraduate Scholarship (#2021932).


Asunto(s)
Células Asesinas Naturales , Receptores de IgG , Transducción de Señal , Factor de Crecimiento Transformador beta , Neoplasias de la Vejiga Urinaria , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Neoplasias de la Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/metabolismo , Humanos , Animales , Ratones , Factor de Crecimiento Transformador beta/metabolismo , Receptores de IgG/metabolismo , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Proteínas Ligadas a GPI/metabolismo , Proteínas Ligadas a GPI/genética , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Análisis de la Célula Individual , Femenino
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