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1.
Cancers (Basel) ; 15(13)2023 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-37444578

RESUMO

Various cancer cell-associated intrinsic and extrinsic inputs act on YAP/TAZ proteins to mediate the hyperactivation of the TEAD transcription factor-based transcriptome. This YAP/TAZ-TEAD activity can override the growth-limiting Hippo tumor-suppressor pathway that maintains normal tissue homeostasis. Herein, we provide an integrated summary of the contrasting roles of YAP/TAZ during normal tissue homeostasis versus tumor initiation and progression. In addition to upstream factors that regulate YAP/TAZ in the TME, critical insights on the emerging functions of YAP/TAZ in immune suppression and abnormal vasculature development during tumorigenesis are illustrated. Lastly, we discuss the current methods that intervene with the YAP/TAZ-TEAD oncogenic signaling pathway and the emerging applications of combination therapies, gut microbiota, and epigenetic plasticity that could potentiate the efficacy of chemo/immunotherapy as improved cancer therapeutic strategies.

3.
Cancers (Basel) ; 13(14)2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34298809

RESUMO

Cancer immunotherapy harnesses the immune system by targeting tumor cells that express antigens recognized by immune system cells, thus leading to tumor rejection. These tumor-associated antigens include tumor-specific shared antigens, differentiation antigens, protein products of mutated genes and rearrangements unique to tumor cells, overexpressed tissue-specific antigens, and exogenous viral proteins. However, the development of effective therapeutic approaches has proven difficult, mainly because these tumor antigens are shielded, and cells primarily express self-derived antigens. Despite innovative and notable advances in immunotherapy, challenges associated with variable patient response rates and efficacy on select tumors minimize the overall effectiveness of immunotherapy. Variations observed in response rates to immunotherapy are due to multiple factors, including adaptative resistance, competency, and a diversity of individual immune systems, including cancer stem cells in the tumor microenvironment, composition of the gut microbiota, and broad limitations of current immunotherapeutic approaches. New approaches are positioned to improve the immune response and increase the efficacy of immunotherapies, highlighting the challenges that the current global COVID-19 pandemic places on the present state of immunotherapy.

4.
Oncotarget ; 12(15): 1470-1489, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34316328

RESUMO

OBJECTIVE: Aberrations in the PI3K/AKT/mTOR survival pathway in many cancers are the most common genomic abnormalities. The phytochemical and bioactive agent sulforaphane (SFN) has nutrigenomic potential in activating the expression of several cellular protective genes via the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). Nrf2 is primarily related to mechanisms of endogenous cellular defense and survival. The efficacy of SFN in combination with acetazolamide (AZ) was investigated in reducing typical H727 and atypical H720 BC survival, migration potential, and apoptosis in vitro and in vivo preclinical xenograft tissues. MATERIALS AND METHODS: Microscopic imaging, immunocytochemistry, wound healing assay, caspase-cleaved cytokeratin 18 (M30, CCK18) CytoDeath ELISA assay, immunofluorescence labeling assays for apoptosis, hypoxia, Western Blotting, Tunnel assay, measurement of 5-HT secretion by carbon fiber amperometry assay, quantitative methylation-specific PCR (qMSP), morphologic changes, cell viability, apoptosis activity and the expression levels of phospho-Akt1, Akt1, HIF-1α, PI3K, p21, CAIX, 5-HT, phospho-mTOR, and mTOR in xenografts derived from typical H727 and atypical H720 BC cell lines. RESULTS: Combining AZ+SFN reduced tumor cell survival compared to each agent alone, both in vitro and in vivo xenograft tissues. AZ+SFN targeted multiple pathways involved in cell cycle, serotonin secretion, survival, and growth pathways, highlighting its therapeutic approach. Both H727 and H720 cells were associated with induction of apoptosis, upregulation of the p21 cell cycle inhibitor, and downregulation of the PI3K/Akt/mTOR pathway, suggesting that the PI3K/Akt/mTOR pathway is a primary target of the AZ+SFN combination therapy. CONCLUSIONS: Combining SFN+AZ significantly inhibits the PI3K/Akt/mTOR pathway and significantly reducing 5-HT secretion in carcinoid syndrome.

5.
Cancers (Basel) ; 13(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205080

RESUMO

Therapeutic targeting of stem cells needs to be strategically developed to control tumor growth and prevent metastatic burden successfully. Breast cancer presents a unique clinical problem because of the variety of cellular subtypes present, including cancer stem cells (CSCs). The development of 3D stem-like properties of human breast tumor spheroids in stem cell factor conditioned media was investigated in orthotopic xenografts for enhanced tumorgenicity in the athymic nude rat model. MCF-7, ZR-75-1, and MDA-MB-231 breast cancer cell lines were cultured in serum-free, stem cell factor-supplemented medium under non-adherent conditions and passaged to generate 3rd generation spheroids. The spheroids were co-cultured with fetal lung fibroblast (FLF) cells before orthotopic heterotransplantation into the mammary fat pads of athymic nude rats. Excised xenografts were assessed histologically by H&E staining and immunohistochemistry for breast cancer marker (ERB1), proliferation marker (Ki67), mitotic marker (pHH3), hypoxia marker (HIF-2α), CSC markers (CD47, CD44, CD24, and CD133), and vascularization markers (CD31, CD34). Breast cancer cells cultured in stem cell factor supplemented medium generated 3D spheroids exhibited increased stem-like characteristics. The 3D stem-like spheroids co-cultured with FLF as supporting stroma reproducibly and efficiently established orthotopic breast cancer xenografts in the athymic nude rat.

6.
Ann Allergy Asthma Immunol ; 125(6): 639-645, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32927048

RESUMO

OBJECTIVE: To review birth cohorts with an exposomal approach and their key outcomes and challenges. Exposome encompasses all human environmental exposures from conception onward. The impact of environmental exposures is greatest in critical stages of life, including fetal and early childhood. Birth cohorts provide a good study setting to assess exposome in the sensitive periods of life. Here, we review birth cohorts with an exposomal approach and their key outcomes and challenges. DATA SOURCES: MEDLINE was searched for birth cohorts that have used an exposomal approach. STUDY SELECTIONS: Relevant studies in English language were selected and reviewed. RESULTS: The outcomes of birth cohorts with an exposomal approach improve our understanding of the association between environmental exposures and childhood diseases. For example, results from The Canadian Healthy Infant Longitudinal Development Study suggest an association between first trimester exposure to traffic-related air pollution and increased risk of allergic sensitization at 12 months of age (P = .6). In a smaller Canadian birth cohort study, it was found that regular use of air fresheners (adjusted P = .04) and presence of mold in the residence (adjusted P < .001) were associated with early childhood wheezing and cough. The application of emerging molecular omics technologies and new analytical tools has facilitated the comprehensive assessment of exposome in birth cohorts. CONCLUSION: Birth cohort studies with an exposomal approach improve our understanding of the origin of childhood diseases by examining a complex network of environmental exposures during pregnancy and years beyond birth. International collaboration is required to develop large birth cohorts for better and more extensive assessment of exposome with standardized protocols and new statistical frameworks.


Assuntos
Expossoma , Doenças do Recém-Nascido/epidemiologia , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Poluição do Ar/efeitos adversos , Poluição do Ar em Ambientes Fechados , Canadá/epidemiologia , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Parto , Gravidez
7.
BMC Cancer ; 19(1): 864, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31470802

RESUMO

BACKGROUND: Bronchial carcinoids are neuroendocrine tumors that present as typical (TC) and atypical (AC) variants, the latter being more aggressive, invasive and metastatic. Studies of tumor initiating cell (TIC) biology in bronchial carcinoids has been hindered by the lack of appropriate in-vitro and xenograft models representing the bronchial carcinoid phenotype and behavior. METHODS: Bronchial carcinoid cell lines (H727, TC and H720, AC) were cultured in serum-free growth factor supplemented medium to form 3D spheroids and serially passaged up to the 3rd generation permitting expansion of the TIC population as verified by expression of stemness markers, clonogenicity in-vitro and tumorigenicity in both subcutaneous and orthotopic (lung) models. Acetazolamide (AZ), sulforaphane (SFN) and the AZ + SFN combination were evaluated for targeting TIC in bronchial carcinoids. RESULTS: Data demonstrate that bronchial carcinoid cell line 3rd generation spheroid cells show increased drug resistance, clonogenicity, and tumorigenic potential compared with the parental cells, suggesting selection and expansion of a TIC fraction. Gene expression and immunolabeling studies demonstrated that the TIC expressed stemness factors Oct-4, Sox-2 and Nanog. In a lung orthotopic model bronchial carcinoid, cell line derived spheroids, and patient tumor derived 3rd generation spheroids when supported by a stroma, showed robust tumor formation. SFN and especially the AZ + SFN combination were effective in inhibiting tumor cell growth, spheroid formation and in reducing tumor formation in immunocompromised mice. CONCLUSIONS: Human bronchial carcinoid tumor cells serially passaged as spheroids contain a higher fraction of TIC exhibiting a stemness phenotype. This TIC population can be effectively targeted by the combination of AZ + SFN. Our work portends clinical relevance and supports the therapeutic use of the novel AZ+ SFN combination that may target the TIC population of bronchial carcinoids.


Assuntos
Acetazolamida/administração & dosagem , Anticarcinógenos/administração & dosagem , Neoplasias Brônquicas/tratamento farmacológico , Tumor Carcinoide/tratamento farmacológico , Isotiocianatos/administração & dosagem , Células-Tronco Neoplásicas/efeitos dos fármacos , Acetazolamida/farmacologia , Animais , Anticarcinógenos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Brônquicas/genética , Neoplasias Brônquicas/metabolismo , Tumor Carcinoide/genética , Tumor Carcinoide/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Isotiocianatos/farmacologia , Camundongos , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Esferoides Celulares/citologia , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Sulfóxidos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Cell Commun Signal ; 12(1): 91-101, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28735362

RESUMO

Cancer is a multi-stage process resulting from aberrant signaling pathways driving uncontrolled proliferation of transformed cells. The development and progression of cancer from a premalignant lesion towards a metastatic tumor requires accumulation of mutations in many regulatory genes of the cell. Different chemopreventative approaches have been sought to interfere with initiation and control malignant progression. Here we present research on dietary compounds with evidence of cancer prevention activity that highlights the potential beneficial effect of a diet rich in cruciferous vegetables. The Brassica family of cruciferous vegetables such as broccoli is a rich source of glucosinolates, which are metabolized to isothiocyanate compounds. Amongst a number of related variants of isothiocyanates, sulforaphane (SFN) has surfaced as a particularly potent chemopreventive agent based on its ability to target multiple mechanisms within the cell to control carcinogenesis. Anti-inflammatory, pro-apoptotic and modulation of histones are some of the more important and known mechanisms by which SFN exerts chemoprevention. The effect of SFN on cancer stem cells is another area of interest that has been explored in recent years and may contribute to its chemopreventive properties. In this paper, we briefly review structure, pharmacology and preclinical studies highlighting chemopreventive effects of SFN.

10.
Oncotarget ; 8(23): 38022-38043, 2017 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-28410237

RESUMO

Combination therapy, a treatment modality that combines two or more therapeutic agents, is a cornerstone of cancer therapy. The amalgamation of anti-cancer drugs enhances efficacy compared to the mono-therapy approach because it targets key pathways in a characteristically synergistic or an additive manner. This approach potentially reduces drug resistance, while simultaneously providing therapeutic anti-cancer benefits, such as reducing tumour growth and metastatic potential, arresting mitotically active cells, reducing cancer stem cell populations, and inducing apoptosis. The 5-year survival rates for most metastatic cancers are still quite low, and the process of developing a new anti-cancer drug is costly and extremely time-consuming. Therefore, new strategies that target the survival pathways that provide efficient and effective results at an affordable cost are being considered. One such approach incorporates repurposing therapeutic agents initially used for the treatment of different diseases other than cancer. This approach is effective primarily when the FDA-approved agent targets similar pathways found in cancer. Because one of the drugs used in combination therapy is already FDA-approved, overall costs of combination therapy research are reduced. This increases cost efficiency of therapy, thereby benefiting the "medically underserved". In addition, an approach that combines repurposed pharmaceutical agents with other therapeutics has shown promising results in mitigating tumour burden. In this systematic review, we discuss important pathways commonly targeted in cancer therapy. Furthermore, we also review important repurposed or primary anti-cancer agents that have gained popularity in clinical trials and research since 2012.


Assuntos
Antineoplásicos/uso terapêutico , Inibidores da Anidrase Carbônica/uso terapêutico , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Humanos , Neoplasias/mortalidade , Neoplasias/patologia , Taxa de Sobrevida
11.
BMC Cancer ; 17(1): 156, 2017 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-28235409

RESUMO

BACKGROUND: Neuroblastoma (NB), a tumor of the primitive neural crest, despite aggressive treatment portends a poor long-term survival for patients with advanced high stage NB. New treatment strategies are required. METHODS: We investigated coordinated targeting of essential homeostatic regulatory factors involved in cancer progression, histone deacetylases (HDACs) and carbonic anhydrases (CAs). RESULTS: We evaluated the antitumor potential of the HDAC inhibitor (HDACi), pyridylmethyl-N-{4-[(2-aminophenyl)-carbamoyl]-benzyl}-carbamate (MS-275) in combination with a pan CA inhibitor, acetazolamide (AZ) on NB SH-SY5Y, SK-N-SH and SK-N-BE(2) cells. The key observation was that the combination AZ + MS-275 significantly inhibited growth, induced cell cycle arrest and apoptosis, and reduced migration capacity of NB cell line SH-SY5Y. In addition, this combination significantly inhibited tumor growth in vivo, in a pre-clinical xenograft model. Evidence was obtained for a marked reduction in tumorigenicity and in the expression of mitotic, proliferative, HIF-1α and CAIX. NB xenografts of SH-SY5Y showed a significant increase in apoptosis. CONCLUSION: MS-275 alone at nanomolar concentrations significantly reduced the putative cancer stem cell (CSC) fraction of NB cell lines, SH-SY5Y and SK-N-BE(2), in reference to NT2/D1, a teratocarcinoma cell line, exhibiting a strong stem cell like phenotype in vitro. Whereas stemness genes (OCT4, SOX2 and Nanog) were found to be significantly downregulated after MS-275 treatment, this was further enhanced by AZ co-treatment. The significant reduction in initial tumorigenicity and subsequent abrogation upon serial xenografting suggests potential elimination of the NB CSC fraction. The significant potentiation of MS-275 by AZ is a promising therapeutic approach and one amenable for administration to patients given their current clinical utility.


Assuntos
Acetazolamida/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Neuroblastoma/tratamento farmacológico , Piridinas/farmacologia , Acetazolamida/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Inibidores da Anidrase Carbônica/farmacologia , Inibidores da Anidrase Carbônica/uso terapêutico , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Camundongos , Piridinas/uso terapêutico , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Plast Reconstr Aesthet Surg ; 68(5): 673-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25687889

RESUMO

PURPOSE: Infections following implant-based breast reconstruction can lead to devastating consequences. There is currently no consensus on the need for post-operative antibiotics in preventing immediate infection. This study compared two different methods of infection prevention in this group of patients. METHOD: A retrospective matched cohort study was performed on consecutive women undergoing implant-based breast reconstruction at University Health Network, Toronto (November 2008-December 2012). All patients received a single pre-operative intravenous antibiotic dose. Group A received minimal interventions and Group B underwent maximal prophylactic measures. Patient (age, smoking, diabetes, co-morbidities), oncologic and procedural variables (timing and laterality) were collected. Univariate and multivariate logistic regression were performed to compare outcomes between the two groups. RESULTS: Two hundred and eight patients underwent 647 implant procedures. After matching the two treatment groups by BMI, 94 patients in each treatment group yielding a total of 605 implant procedures were selected for analysis. The two groups were comparable in terms of patient and disease variables. Post-operative wound infection was similar in Group A (n = 11, 12%) compared with Group B (n = 9, 10%; p = 0.8). Univariate analysis revealed only pre-operative radiotherapy to be associated with the development of infection (0.004). Controlling for the effect of radiotherapy, multivariate analysis demonstrated that there was no statistically significant difference between the two methods for infection prevention. CONCLUSIONS: Our findings suggest that a single pre-operative dose of intravenous antibiotics is equally as effective as continued antibiotic prophylaxis in preventing immediate infection in patients undergoing implant-based breast reconstructions.


Assuntos
Antibacterianos/administração & dosagem , Antibioticoprofilaxia/métodos , Implante Mamário/métodos , Celulite (Flegmão)/prevenção & controle , Infecção da Ferida Cirúrgica/prevenção & controle , Implante Mamário/efeitos adversos , Celulite (Flegmão)/epidemiologia , Celulite (Flegmão)/etiologia , Estudos de Coortes , Comorbidade , Diabetes Mellitus/epidemiologia , Esquema de Medicação , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Mamoplastia/efeitos adversos , Mamoplastia/métodos , Pessoa de Meia-Idade , Análise Multivariada , Cuidados Pós-Operatórios , Estudos Retrospectivos , Fumar/epidemiologia , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia
13.
Plast Surg (Oakv) ; 22(1): 39-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25152646

RESUMO

Several surgical techniques have been described for auricular reconstruction. Autologous reconstruction using costal cartilage is the most widely accepted technique of microtia repair. However, other techniques have certain indications and should be discussed with patients and families when planning for an auricular reconstruction. In the present review, the authors discuss the main surgical techniques for auricular reconstruction including autologous costal cartilage graft, Medpor (Stryker, USA) implant and prosthetic reconstruction. To further elaborate on the advantages and disadvantages of each technique, the authors invited leaders in this field, Dr Nagata, Dr Park, Dr Reinisch and Dr Wilkes, to comment on their own technique and provide examples of their methods.


Plusieurs techniques chirurgicales de reconstruction auriculaire ont déjà été décrites. La reconstruction autologue à l'aide de cartilage costal est la technique la plus acceptée pour la réparation des microties. Cependant, d'autres techniques sont parfois indiquées et devraient être proposées aux patients et à leur famille au moment de planifier une reconstruction auriculaire. Dans la présente analyse, les auteurs traitent des principales techniques chirurgicales de reconstruction auriculaire, y compris la greffe de cartilage costal autologue, l'implant Medpor (Stryker, États-Unis) et la reconstruction prosthétique. Pour traiter des avantages et inconvénients de chaque technique, les auteurs ont invité les docteurs Nagata, Park, Reinish et Wilkes, chefs de file dans ce domaine, à commenter leur propre technique et à donner des exemples de leurs méthodes.

14.
J Plast Reconstr Aesthet Surg ; 66(5): 726-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22981385

RESUMO

A number of tendon transfers have been described for opponensplasty. Transfer of the palmaris longus (PL) tendon with a palmar fascial extension was initially described by Camitz. This technique has mostly been combined with carpal tunnel release in patients with long standing median neuropathy with atrophy of the thenar muscles. However, the Camitz transfer has not been previously described in the setting of pediatric median nerve injury. We report 4 cases of Camitz transfer in pediatric patients with median nerve injuries. Four children (all female; age range 3-15 yrs) underwent PL tendon transfer following median nerve injury. The causes of injury included trauma, iatrogenic injury, and neuritis of the brachial plexus. The Camitz procedure was performed at the time of median nerve decompression and/or reconstruction. All patients had excellent early return of function. Transfer of the palmaris longus tendon reliably restores palmar abduction, with minimal to no additional morbidity, in carefully selected pediatric patients with median nerve injury undergoing release of the carpal tunnel.


Assuntos
Síndrome do Túnel Carpal/cirurgia , Traumatismos do Antebraço/complicações , Nervo Mediano/cirurgia , Músculo Esquelético/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Transferência Tendinosa/métodos , Síndrome do Túnel Carpal/etiologia , Criança , Feminino , Traumatismos do Antebraço/cirurgia , Humanos , Nervo Mediano/lesões
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