RESUMO
Tubulin associated unit has been extensively studied in neurodegenerative diseases including Alzheimer's disease (AD), whereby its hyperphosphorylation and accumulation contributes to disease pathogenesis. Tau is abundantly expressed in the central nervous system but is also present in non-neuronal tissues and in tumours including sex hormone responsive cancers such as breast and prostate. Curiously, hormonal effects on tau also exist in an AD context from numerous studies on menopause, hormone replacement therapy, and androgen deprivation therapy. Despite sharing some risk factors, most importantly advancing age, there are numerous reports from population studies of, currently poorly explained inverse associations between cancer and Alzheimer's disease. We previously reviewed important components of the phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) signalling pathway and their differential modulation in relation to the two diseases. Similarly, receptor tyrosine kinases, estrogen receptor and androgen receptor have all been implicated in the pathogenesis of both cancer and AD. In this review, we focus on tau and its effects in hormone responsive cancer in terms of development, progression, and treatment and in relation to sex hormones and PI3K/Akt signalling molecules including IRS-1, PTEN, Pin1, and p53.
Assuntos
Doença de Alzheimer , Hormônios Esteroides Gonadais , Transdução de Sinais , Proteínas tau , Humanos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/tratamento farmacológico , Proteínas tau/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Transdução de Sinais/efeitos dos fármacos , Feminino , Masculino , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Fosfatidilinositol 3-Quinases/metabolismoRESUMO
Bladder cancer is the tenth most common cancer and is a significant burden on health care services worldwide, as it is one of the most costly cancers to treat per patient. This expense is due to the extensive treatment and follow-ups that occur with costly and invasive procedures. Improvement in both treatment options and the quality of life these interventions offer has not progressed at the rates of other cancers, and new alternatives are desperately needed to ease the burden. A more modern approach needs to be taken, with urinary biomarkers being a positive step in making treatments more patient-friendly, but there is still a long way to go to make these widely available and of a comparable standard to the current treatment options. New targets to hit the major signalling pathways that are upregulated in bladder cancer, such as the PI3K/AkT/mTOR pathway, are urgently needed, with only one drug approved so far, Erdafitinib. Immune checkpoint inhibitors also hold promise, with both PD-1 and CDLA-4 antibody therapies approved for use. They effectively block ligand/receptor binding to block the immune checkpoint used by tumour cells. Other avenues must be explored, including drug repurposing and novel biomarkers, which have revolutionised this area in other cancers.
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Qualidade de Vida , Neoplasias da Bexiga Urinária , Humanos , Fosfatidilinositol 3-Quinases , Cistectomia/métodos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Biomarcadores , Invasividade Neoplásica/patologiaRESUMO
BACKGROUND: Prostate cancer (PrCa) is the second most prevalent malignancy in men worldwide. Observational studies have linked the use of low-density lipoprotein cholesterol (LDL-c) lowering therapies with reduced risk of PrCa, which may potentially be attributable to confounding factors. In this study, we performed a drug target Mendelian randomisation (MR) analysis to evaluate the association of genetically proxied inhibition of LDL-c-lowering drug targets on risk of PrCa. METHODS AND FINDINGS: Single-nucleotide polymorphisms (SNPs) associated with LDL-c (P < 5 × 10-8) from the Global Lipids Genetics Consortium genome-wide association study (GWAS) (N = 1,320,016) and located in and around the HMGCR, NPC1L1, and PCSK9 genes were used to proxy the therapeutic inhibition of these targets. Summary-level data regarding the risk of total, advanced, and early-onset PrCa were obtained from the PRACTICAL consortium. Validation analyses were performed using genetic instruments from an LDL-c GWAS conducted on male UK Biobank participants of European ancestry (N = 201,678), as well as instruments selected based on liver-derived gene expression and circulation plasma levels of targets. We also investigated whether putative mediators may play a role in findings for traits previously implicated in PrCa risk (i.e., lipoprotein a (Lp(a)), body mass index (BMI), and testosterone). Applying two-sample MR using the inverse-variance weighted approach provided strong evidence supporting an effect of genetically proxied inhibition of PCSK9 (equivalent to a standard deviation (SD) reduction in LDL-c) on lower risk of total PrCa (odds ratio (OR) = 0.85, 95% confidence interval (CI) = 0.76 to 0.96, P = 9.15 × 10-3) and early-onset PrCa (OR = 0.70, 95% CI = 0.52 to 0.95, P = 0.023). Genetically proxied HMGCR inhibition provided a similar central effect estimate on PrCa risk, although with a wider 95% CI (OR = 0.83, 95% CI = 0.62 to 1.13, P = 0.244), whereas genetically proxied NPC1L1 inhibition had an effect on higher PrCa risk with a 95% CI that likewise included the null (OR = 1.34, 95% CI = 0.87 to 2.04, P = 0.180). Analyses using male-stratified instruments provided consistent results. Secondary MR analyses supported a genetically proxied effect of liver-specific PCSK9 expression (OR = 0.90 per SD reduction in PCSK9 expression, 95% CI = 0.86 to 0.95, P = 5.50 × 10-5) and circulating plasma levels of PCSK9 (OR = 0.93 per SD reduction in PCSK9 protein levels, 95% CI = 0.87 to 0.997, P = 0.04) on PrCa risk. Colocalization analyses identified strong evidence (posterior probability (PPA) = 81.3%) of a shared genetic variant (rs553741) between liver-derived PCSK9 expression and PrCa risk, whereas weak evidence was found for HMGCR (PPA = 0.33%) and NPC1L1 expression (PPA = 0.38%). Moreover, genetically proxied PCSK9 inhibition was strongly associated with Lp(a) levels (Beta = -0.08, 95% CI = -0.12 to -0.05, P = 1.00 × 10-5), but not BMI or testosterone, indicating a possible role for Lp(a) in the biological mechanism underlying the association between PCSK9 and PrCa. Notably, we emphasise that our estimates are based on a lifelong exposure that makes direct comparisons with trial results challenging. CONCLUSIONS: Our study supports a strong association between genetically proxied inhibition of PCSK9 and a lower risk of total and early-onset PrCa, potentially through an alternative mechanism other than the on-target effect on LDL-c. Further evidence from clinical studies is needed to confirm this finding as well as the putative mediatory role of Lp(a).
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Pró-Proteína Convertase 9 , Neoplasias da Próstata , Humanos , Masculino , Pró-Proteína Convertase 9/genética , Estudo de Associação Genômica Ampla , LDL-Colesterol , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/genética , Testosterona , Análise da Randomização MendelianaRESUMO
The insulin-like growth factor axis is a multifaceted, complex system that comprises two ligands, IGF-I and IGF-II, receptors (IGF-1R, IGF-IIR, insulin receptor isoforms IR-A and B, and hybrid receptors) six high affinity IGF-binding proteins (IGFBPs 1-6), and IGFBP proteases [...].
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Fator de Crescimento Insulin-Like II , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Ligação Proteica , Proteína 6 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismoRESUMO
Insulin receptor substrate-2 (IRS-2), a substrate of the insulin-like growth factor (IGF)-I receptor, is highly expressed in the prostate cancer cell line, PC3. We recently demonstrated that extracellular signal-regulated kinase (Erk1/2), a kinase downstream of IGF signaling, is activated in PC3 cells under serum starvation, and this activation can be inhibited by IRS-2 knockdown. Here, we observed that adding an IGF-I-neutralizing antibody to the culture medium inhibited the activation of Erk1/2. Suppression of Erk1/2 in IRS-2 knockdown cells was restored by the addition of a PC3 serum-free conditioned medium. In contrast, the IRS-2-silenced PC3 conditioned medium could not restore Erk1/2 activation, suggesting that IRS-2 promotes the secretion of proteins that activate the IGF signaling pathway. Furthermore, gelatin zymography analysis of the conditioned medium showed that matrix metalloproteinase-9 (MMP-9) was secreted extracellularly in an IRS-2 dependent manner when PC3 was cultured under serum starvation conditions. Moreover, MMP-9 knockdown suppressed Erk1/2 activation, DNA synthesis, and migratory activity. The IRS-2 levels were positively correlated with Gleason grade in human prostate cancer tissues. These data suggest that highly expressed IRS-2 activates IGF signaling by enabling the secretion of MMP-9, which is associated with hyperproliferation and malignancy of prostate cancer cell line, PC3.
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Carcinoma , Neoplasias da Próstata , Humanos , Masculino , Carcinoma/metabolismo , Linhagem Celular , Meios de Cultivo Condicionados/metabolismo , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Células PC-3 , Fosfoproteínas/metabolismo , Fosforilação , Próstata/patologia , Neoplasias da Próstata/metabolismoRESUMO
AIMS/HYPOTHESIS: Podocyte loss or injury is one of the earliest features observed in the pathogenesis of diabetic kidney disease (DKD), which is the leading cause of end-stage renal failure worldwide. Dysfunction in the IGF axis, including in IGF binding proteins (IGFBPs), is associated with DKD, particularly in the early stages of disease progression. The aim of this study was to investigate the potential roles of IGFBPs in the development of type 2 DKD, focusing on podocytes. METHODS: IGFBP expression was analysed in the Pima DKD cohort, alongside data from the Nephroseq database, and in ex vivo human glomeruli. Conditionally immortalised human podocytes and glomerular endothelial cells were studied in vitro, where IGFBP-1 expression was analysed using quantitative PCR and ELISAs. Cell responses to IGFBPs were investigated using migration, cell survival and adhesion assays; electrical cell-substrate impedance sensing; western blotting; and high-content automated imaging. RESULTS: Data from the Pima DKD cohort and from the Nephroseq database demonstrated a significant reduction in glomerular IGFBP-1 in the early stages of human type 2 DKD. In the glomerulus, IGFBP-1 was predominantly expressed in podocytes and controlled by phosphoinositide 3-kinase (PI3K)-forkhead box O1 (FoxO1) activity. In vitro, IGFBP-1 signalled to podocytes via ß1-integrins, resulting in increased phosphorylation of focal-adhesion kinase (FAK), increasing podocyte motility, adhesion, electrical resistance across the adhesive cell layer and cell viability. CONCLUSIONS/INTERPRETATION: This work identifies a novel role for IGFBP-1 in the regulation of podocyte function and that the glomerular expression of IGFBP-1 is reduced in the early stages of type 2 DKD, via reduced FoxO1 activity. Thus, we hypothesise that strategies to maintain glomerular IGFBP-1 levels may be beneficial in maintaining podocyte function early in DKD.
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Diabetes Mellitus Tipo 2/patologia , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Glomérulos Renais/metabolismo , Podócitos/metabolismo , Biópsia , Células Cultivadas , Estudos de Coortes , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Integrina beta1/metabolismo , Rim/metabolismo , Rim/patologia , Glomérulos Renais/patologia , Podócitos/patologia , Transdução de Sinais/genéticaRESUMO
There is considerable evidence of a positive association between the incidence of type 2 diabetes mellitus (T2DM) and obesity with bladder cancer (BCa), with the link between T2DM and obesity having already been established. There also appear to be potential associations between Pleckstrin homology domain containing S1 (PLEKHS1) and the Insulin-like Growth Factor (IGF) axis. Seven literature searches were carried out to investigate the backgrounds of these potential links. PLEKHS1 is a candidate biomarker in BCa, with mutations that are easily detectable in urine and increased expression seemingly associated with worse disease states. PLEKHS1 has also been implicated as a potential mediator for the onset of T2DM in people with obesity. The substantial evidence of the involvement of IGF in BCa, the role of the IGF axis in obesity and T2DM, and the global prevalence of T2DM and obesity suggest there is scope for investigating the links between these components. Preliminary findings on the relationship between PLEKHS1 and the IGF axis signal possible associations with BCa progression. This indicates that PLEKHS1 plays a role in the pathogenesis of BCa that may be mediated by members of the IGF axis. Further detailed research is needed to establish the relationship between PLEKHS1 and the IGF axis in BCa and determine how these phenomena overlap with T2DM and obesity.
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Diabetes Mellitus Tipo 2/complicações , Obesidade/complicações , Neoplasias da Bexiga Urinária/etiologia , Animais , Biomarcadores Tumorais/genética , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Obesidade/epidemiologia , Obesidade/genética , Fatores de Risco , Transdução de Sinais/genética , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/genéticaRESUMO
Hyperglycaemia is a common metabolic alteration associated with breast cancer risk and progression. We have previously reported that BRCA1 restrains metabolic activity and proliferative response to IGF-I anabolic actions in breast cancer cells cultured in high glucose. Here, we evaluated the impact of normal physiological glucose on these tumour suppressive roles of BRCA1. Human breast cancer cells cultured in normal physiological and high glucose were treated with IGF-I (0-500 ng/mL). Cellular responses were evaluated using immunoblotting, co-immunoprecipitation, and cell viability assay. As we previously reported, IGF-I induced ACCA dephosphorylation by reducing the association between BRCA1 and phosphorylated ACCA in high glucose, and upregulated FASN abundance downstream of ACCA. However, these effects were not observed in normal glucose. Normal physiological glucose conditions completely blocked IGF-I-induced ACCA dephosphorylation and FASN upregulation. Co-immunoprecipitation studies showed that normal physiological glucose blocked ACCA dephosphorylation by increasing the association between BRCA1 and phosphorylated ACCA. Compared to high glucose, the proliferative response of breast cancer cells to IGF-I was reduced in normal glucose, whereas no difference was observed in normal mammary epithelial cells. Considering these results collectively, we conclude that normal physiological glucose promotes the novel function of BRCA1 as a metabolic restraint of IGF-I actions. These data suggest that maintaining normal glucose levels may improve BRCA1 function in breast cancer and slow down cancer progression.
Assuntos
Proteína BRCA1/metabolismo , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Glucose/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Lipogênese/efeitos dos fármacos , Meios de Cultura/farmacologia , Ácido Graxo Sintase Tipo I/metabolismo , Feminino , Glucose/metabolismo , Humanos , Células MCF-7 , Fosforilação/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismoRESUMO
BACKGROUND: Diets that restrict energy or macronutrient intake (e.g. fasting/ketogenic diets (KDs)) may selectively protect non-tumour cells during cancer treatment. Previous reviews have focused on a subset of dietary restrictions (DR) or have not performed systematic searches. We conducted a systematic scoping review of DR at the time of cancer treatment. METHODS: MEDLINE, Embase, CINAHL, AMED and Web of Science databases were searched for studies of adults undergoing DR alongside treatment for cancer. Search results were screened against inclusion/exclusion criteria. Data from included studies were extracted by two independent reviewers. Results were summarised narratively. RESULTS: Twenty-three independent studies (34 articles), with small sample sizes, met the inclusion criteria. Four categories were identified: KDs (10 studies), fasting (4 studies), protein restriction (5 studies) and combined interventions (4 studies). Diets were tolerated well, however adherence was variable, particularly for KDs. Biomarker analysis in KDs and fasting resulted in the expected increase in ketones or reduction in insulin-like growth factors, respectively, however they did not reduce glucose. CONCLUSIONS: Future research with adequately powered studies is required to test the effects of each DR intervention on treatment toxicities and outcomes. Further research into improving adherence to DR may improve the feasibility of larger trials.
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Dieta Cetogênica , Dieta com Restrição de Proteínas , Jejum , Neoplasias/dietoterapia , Neoplasias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Neoplasias/metabolismo , Adulto JovemRESUMO
The IGF system has an important role in growth and development. IGF-II is a recognized fetal growth promoter. However, its physiological postnatal role remains uncertain, although it is maintained in the circulation at a substantially high level throughout life. IGF-II has been strongly linked to obesity in genetic studies, and more recent evidence suggests a metabolic role. We examined fat depot differences in IGF-II's action on differentiation and metabolism. We speculate a specific effect on visceral adipocytes in relation to the differential distribution of insulin receptors between visceral and subcutaneous fat depots. We used a previously established adipocyte, cell culture system of matched pairs of visceral and subcutaneous fat biopsies from 20 normal weight children undergoing routine surgery for nonmalignant, nonseptic conditions. Preadipocytes were differentiated for 14 days in the presence or absence of IGF-II. Oil Red O staining, Western blotting, and reverse transcription polymerase chain reaction techniques were employed to assess levels of adipogenesis markers and levels of the insulin receptor and insulin receptor isoforms. Our data indicate that IGF-II promotes preadipocyte differentiation in subcutaneous preadipocytes but showed a protective, opposing effect restricting visceral preadipocyte differentiation, confirmed by reductions in the differentiation markers peroxisome proliferator-activated receptor gamma and adiponectin and in triglyceride staining. Additionally, IGF-II reduced mRNA expression of the insulin receptor in adipocytes and downregulated insulin receptor isoform A and glucose transporter 4 abundance and corresponding glucose uptake in visceral adipocytes. In conclusion, IGF-II is a regulator of preadipocyte differentiation and metabolism by acting as a differential modulator of fat accumulation favoring less visceral fat deposition in children.
Assuntos
Adipócitos/metabolismo , Adipogenia/fisiologia , Fator de Crescimento Insulin-Like II/metabolismo , Gordura Intra-Abdominal/metabolismo , Células Cultivadas , Criança , Pré-Escolar , Feminino , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Humanos , Lactente , Recém-Nascido , Masculino , Receptor de Insulina/metabolismoRESUMO
PURPOSE: To establish whether the association between milk intake and prostate cancer operates via the insulin-like growth factor (IGF) pathway (including IGF-I, IGF-II, IGFBP-1, IGFBP-2, and IGFBP-3). METHODS: Systematic review, collating data from all relevant studies examining associations of milk with IGF, and those examining associations of IGF with prostate cancer risk and progression. Data were extracted from experimental and observational studies conducted in either humans or animals, and analyzed using meta-analysis where possible, with summary data presented otherwise. RESULTS: One hundred and seventy-two studies met the inclusion criteria: 31 examining the milk-IGF relationship; 132 examining the IGF-prostate cancer relationship in humans; and 10 animal studies examining the IGF-prostate cancer relationship. There was moderate evidence that circulating IGF-I and IGFBP-3 increase with milk (and dairy protein) intake (an estimated standardized effect size of 0.10 SD increase in IGF-I and 0.05 SD in IGFBP-3 per 1 SD increase in milk intake). There was moderate evidence that prostate cancer risk increased with IGF-I (Random effects meta-analysis OR per SD increase in IGF-I 1.09; 95% CI 1.03, 1.16; n = 51 studies) and decreased with IGFBP-3 (OR 0.90; 0.83, 0.98; n = 39 studies), but not with other growth factors. The IGFBP-3 -202A/C single nucleotide polymorphism was positively associated with prostate cancer (pooled OR for A/C vs. AA = 1.22; 95% CI 0.84, 1.79; OR for C/C vs. AA = 1.51; 1.03, 2.21, n = 8 studies). No strong associations were observed for IGF-II, IGFBP-1 or IGFBP-2 with either milk intake or prostate cancer risk. There was little consistency within the data extracted from the small number of animal studies. There was additional evidence to suggest that the suppression of IGF-II can reduce tumor size, and contradictory evidence with regards to the effect of IGFBP-3 suppression on tumor progression. CONCLUSION: IGF-I is a potential mechanism underlying the observed associations between milk intake and prostate cancer risk.
Assuntos
Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Leite/efeitos adversos , Neoplasias da Próstata/metabolismo , Animais , Progressão da Doença , Humanos , Masculino , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia , RiscoRESUMO
The age-related epithelial cancers of the breast, colorectum and prostate are the most prevalent and are increasing in our aging populations. Epithelial cells turnover rapidly and mutations naturally accumulate throughout life. Most epithelial cancers arise from this normal mutation rate. All elderly individuals will harbour many cells with the requisite mutations and most will develop occult neoplastic lesions. Although essential for initiation, these mutations are not sufficient for the progression of cancer to a life-threatening disease. This progression appears to be dependent on context: the tissue ecosystem within individuals and lifestyle exposures across populations of individuals. Together, this implies that the seeds may be plentiful but they only germinate in the right soil. The incidence of these cancers is much lower in Eastern countries but is increasing with Westernisation and increases more acutely in migrants to the West. A Western lifestyle is strongly associated with perturbed metabolism, as evidenced by the epidemics of obesity and diabetes: this may also provide the setting enabling the progression of epithelial cancers. Epidemiology has indicated that metabolic biomarkers are prospectively associated with cancer incidence and prognosis. Furthermore, within cancer research, there has been a rediscovery that a switch in cell metabolism is critical for cancer progression but this is set within the metabolic status of the host. The seed may only germinate if the soil is fertile. This perspective brings together the different avenues of investigation implicating the role that metabolism may play within the context of post-genomic concepts of cancer.
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Neoplasias Epiteliais e Glandulares/etiologia , Animais , Biomarcadores , Carcinógenos , Comorbidade , Progressão da Doença , Meio Ambiente , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Genômica , Humanos , Estilo de Vida , Mutação , Metástase Neoplásica , Neoplasias Epiteliais e Glandulares/epidemiologia , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de SinaisRESUMO
Breast cancer progression is associated with loss of estrogen receptor (ER-α), often due to epigenetic silencing. IGFBP genes have consistently been identified among the most common to be aberrantly methylated in tumours. To understand the impact of losing IGFBP-3 tumour expression via DNA methylation, we treated four breast cancer cell lines (MCF-7, T47D, Hs578T and MDA-MB-231) with a DNA methyltransferase inhibitor, 5-Aza-2'-deoxycytidine (AZA) to determine IGFBP-3's role in the effects of AZA on total cell number and survival relative to changes in the ER. AZA induced cell growth inhibition, death and a reduction in the formation of colonies, despite increasing ER-α expression in ER-negative cells but reducing ER-α in ER-positive cells. Regardless of the differential effects on the ER-α, AZA consistently increased the abundance of IGFBP-3 and negating this increase in IGFBP-3 with siRNA reduced the AZA-induced growth inhibition and induction of cell death and virtually negated the AZA-induced inhibition of colony formation. With ER-α positive cells AZA increased the abundance of the tumour suppressor gene, p53 and induced demethylation of the IGFBP-3 promoter, whereas with ER negative cells, AZA epigenetically increased the transcription factor AP2-α, which when silenced prevented the increase in IGFBP-3. IGFBP-3 plays an important role in the anti-tumorigenic effects of AZA on breast cancer cells.
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Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/análogos & derivados , Neoplasias da Mama/metabolismo , Transformação Celular Neoplásica/efeitos dos fármacos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Azacitidina/farmacologia , Neoplasias da Mama/patologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Metilação de DNA , Decitabina , Epigênese Genética , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Inativação Gênica , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Células MCF-7 , RNA Interferente Pequeno , Fator de Transcrição AP-2/metabolismo , Proteína Supressora de Tumor p53/metabolismoRESUMO
Brain tumours reduce life expectancy for an average of 20 years per patient, the highest of any cancer. A third of brain tumour patients visit their GP at least five times before diagnosis and many of those are diagnosed late through emergency departments. A possible solution to this challenge is to utilise a "liquid biopsy" blood test designed for circulating tumour cells (CTCs). Such a test could be applied at a primary healthcare centre, contributing to informed decision making for diagnostic imaging referrals. Furthermore, it could also be applied at secondary health care centres for the ongoing monitoring of disease recurrence. There is increased interest in CTC enrichment methods as a potential approach for faster diagnosis and monitoring of disease progression. The aim of this review to compare four CTC enrichment methods - OncoQuick®, Screen Cell®, pluriBead® and Cell Search® - with the objective of identifying a suitable method for application in the clinical setting for the isolation of CTCs from glioblastomas.
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The role if insulin-like growth factor binding protein-2 (IGFBP-2) in mediating chemoresistance in breast cancer cells has been demonstrated, but the mechanism of action is unclear. This study aimed to further investigate the role of IGFBP-2 in the DNA damage response induced by etoposide in MCF-7, T47D (ER+ve), and MDA-MB-231 (ER-ve) breast cancer cell lines. In the presence or absence of etoposide, IGFBP-2 was silenced using siRNA in the ER-positive cell lines, or exogenous IGFBP-2 was added to the ER-negative MDA-MB-231 cells. Cell number and death were assessed using trypan blue dye exclusion assay, changes in abundance of proteins were monitored using Western blotting of whole cell lysates, and localization and abundance were determined using immunofluorescence and cell fractionation. Results from ER-positive cell lines demonstrated that upon exposure to etoposide, loss of IGFBP-2 enhanced cell death, and this was associated with a reduction in P-DNA-PKcs and an increase in γH2AX. Conversely, with ER-negative cells, the addition of IGFBP-2 in the presence of etoposide resulted in cell survival, an increase in P-DNA-PKcs, and a reduction in γH2AX. In summary, IGFBP-2 is a survival factor for breast cancer cells that is associated with enhancement of the DNA repair mechanism.
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There have been over 100 cases of Rapid-onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) syndrome reported, but there is currently no curative treatment for children with this condition. We aimed to better characterise adipose cells from a child with ROHHAD syndrome. We isolated pre-adipocytes from a 4 year-old female patient with ROHHAD syndrome and assessed proliferation rate of these cells. We evaluated levels of DLP-Pref-1(pre-adipocyte marker) using western blotting, and concentrations of interleukin-6(IL-6) using ELISA. We performed next-generation sequencing (NGS) and bioinformatic analyses on these cells compared to tissue from an age/sex-matched control. The two most up-/down-regulated genes were validated using QPCR. We successfully isolated pre-adipocytes from a fat biopsy, by confirming the presence of Pref-1 and differentiated them to mature adipocytes. Interleukin 6, (Il-6) levels were 5.6-fold higher in ROHHAD cells compared to a control age/sex-matched biopsy. NGS revealed 25,703 differentially expressed genes (DEGs) from ROHHAD cells vs. control of which 2,237 genes were significantly altered. The 20 most significantly up/down-regulated genes were selected for discussion. This paper describes the first transcriptomic analysis of adipose cells from a child with ROHHAD vs. normal control adipose tissue as a first step in identifying targetable pathways/mechanisms underlying this condition with novel therapeutic interventions.
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BACKGROUND: The overall survival of IDH-wildtype glioblastoma patients is poor despite best available treatments. There is an urgent need for new biomarkers to inform more precise disease stratification. Previous studies have identified insulin-like growth factor binding protein-2 (IGFBP-2) as a potential biomarker for glioblastoma diagnosis and therapeutic targeting. Other studies have indicated links between the insulin-like growth factor (IGF) axis and tumorigenic functions of a molecular chaperone glucose related protein of 78 kDa (GRP78). We aimed to interrogate the oncogenic effects of IGFBP-2 and GRP78 in our glioma stem cell (GSC) lines and clinical cohort. METHODS: Immunoblotting, reverse transcription quantitative real-time PCR were used to quantify protein and mRNA levels derived from GSCs and non-malignant neural stem cells (NSCs). Microarray analysis was used to compare the differences in IGFBP-2 (IGFBP-2) and GRP78 (HSPA5) transcript expression between NSCs, GSCs and adult human cortex samples. Immunohistochemistry was used to quantify IGFBP-2 and GRP78 expression in IDH-wildtype glioblastoma tissue sections (n = 92) and clinical implications assessed using survival analysis. Finally, the relationship between IGFBP-2 and GRP78 was further explored molecularly using coimmunoprecipitation. RESULTS: Here, we demonstrate that IGFBP-2 and HSPA5 mRNA is overexpressed in GSCs and NSCs in comparison to non-malignant brain tissue. We also determined a relationship in which G144 and G26 GSCs expressed higher IGFBP-2 protein and mRNA than GRP78, and this was reversed in mRNA isolated from adult human cortex samples. Clinical cohort analysis revealed that Glioblastomas with high IGFBP-2 protein expression paired with low GRP78 protein expression were significantly associated with a much shorter survival time (Median = 4 months, p = 0.019) compared with 12-14 months for any other combination of high/low protein expression. CONCLUSIONS: Inverse levels of IGFBP-2 and GRP78 may be adverse clinical prognostic markers in IDH-wildtype glioblastoma. Further interrogation of the mechanistic link between IGFBP-2 and GRP78 may be important for rationalisation of their potential as biomarkers and therapeutic targets.
Assuntos
Glioblastoma , Adulto , Humanos , Biomarcadores , Chaperona BiP do Retículo Endoplasmático , Glioblastoma/patologia , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fator de Crescimento Insulin-Like I/metabolismo , Prognóstico , RNA Mensageiro/genéticaRESUMO
AIMS: To examine associations between the transcription factors CCCTC-binding factor (CTCF) and forkhead box protein A1 (FOXA1) and the androgen receptor (AR) and their association with components of the insulin-like growth factor (IGF)-pathway in a cohort of men with localized prostate cancer. METHODS: Using prostate tissue samples collected during the Prostate cancer: Evidence of Exercise and Nutrition Trial (PrEvENT) trial (N = 70 to 92, depending on section availability), we assessed the abundance of CTCF, FOXA1, AR, IGFIR, p-mTOR, PTEN and IGFBP-2 proteins using a modified version of the Allred scoring system. Validation studies were performed using large, publicly available datasets (TCGA) (N = 489). RESULTS: We identified a strong correlation between CTCF and AR staining with benign prostate tissue. CTCF also strongly associated with the IGFIR, with PTEN and with phospho-mTOR. FOXA1 was also correlated with staining for the IGF-IR, with IGFBP-2 and with staining for activated phosphor-mTOR. The staining for the IGF-IR was strongly correlated with the AR. CONCLUSION: Our findings emphasise the close and complex links between the endocrine controls, well known to play an important role in prostate cancer, and the transcription factors implicated by the recent genetic evidence.
Assuntos
Neoplasias da Próstata , Somatomedinas , Masculino , Humanos , Androgênios , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fator de Ligação a CCCTC/genética , Linhagem Celular Tumoral , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Somatomedinas/genética , Somatomedinas/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismoRESUMO
BACKGROUND: Polycystic ovary syndrome (PCOS) affects 10-12% of women of reproductive age. The prevalence of infertility in women with PCOS is high at between 70 and 80%. Treatment initially includes recommendations to follow preconception guidelines, such as lifestyle changes, folic acid therapy and halting the consumption of tobacco and alcohol. Management with pharmacological agents and surgical procedures have been incorporated into treatment regimens to improve fertility. Of these, metformin, an insulin sensitizer used as oral hypoglycemic agent, is gaining popularity. OBJECTIVES: The aim of this study was to perform a meta-analysis of randomized controlled trials (RCTs) to evaluate the role of metformin in improving the reproduction outcomes for non-obese, infertile women with polycystic ovary syndrome. SEARCH METHODS: In June 2019, we searched PubMed (from inception to present), Ovid Medline, Ovid EMBASE, Scopus, and the Cochrane library without date or language restrictions for relevant RCTs. Search was then updated in April 2020. Bibliographies of included studies were also searched for eligible studies. SELECTION CRITERIA: RCTs that compared the effectiveness of metformin with other modalities in treating infertility in non-obese women with PCOS were included. The eligible outcomes for inclusion were pregnancy rate, miscarriage rate, live birth rate, ovarian hyperstimulation (OHSS) and multiple pregnancy. DATA COLLECTION AND ANALYSIS: Data extraction and study quality assessment were performed independently by two reviewers, and any disagreements resolved by consensus or by arbitration by a third reviewer. Where two or more studies reported on the same outcome a meta-analysis was conducted using Cochrane RevMan 5. RESULTS: We found 21 RCTs which were eligible for inclusion in our systematic review, including 2638 patients with PCOS. Our meta-analysis showed that the use of metformin in non-obese women with PCOS is associated with slight increase in clinical pregnancy rate compared to placebo (47.7% vs. 42.9%) (Pooled risk ratio = 1.08 [0.82, 1.42], 95% CI, p = 0.60). It also showed that metformin is comparable to clomiphene citrate (CC) when the outcome is clinical pregnancy rate and the risk of multiple pregnancies tended to be lower (Pooled risk ratio = 0.36 [0.07, 1.92], 95% CI, p = 0.23, 3 studies). However, metformin had a higher risk of miscarriage rate (Pooled risk ratio = 2.41 [0.39, 14.86], 95% CI, p = 0.72). Furthermore, this analysis suggested that adding metformin to CC treatment decreases miscarriage risk by two folds compared to metformin alone (Pooled risk ratio = 2.67 [1.32, 5.39], 95% CI, p = 0.006) and showed no difference compared to CC alone. In comparison to letrozole, combination of metformin and CC is associated with lower clinical pregnancy rate (Pooled risk ratio = 0.52 [0.14, 1.91] 95% CI, p = 0.33) and multiple pregnancies (Pooled risk ratio = 0.45 [0.06, 3.19] 95% CI, p = 0.42). CONCLUSION: Although this study illustrated that metformin may be better than placebo for some pregnancy outcomes, stronger, more definitive evidence from sufficiently powered trials are required before considering metformin for treating non-obese infertile women with PCOS within the current recommended guidelines.
Assuntos
Infertilidade Feminina , Metformina , Síndrome do Ovário Policístico , Clomifeno/uso terapêutico , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Infertilidade Feminina/complicações , Infertilidade Feminina/etiologia , Nascido Vivo/epidemiologia , Metformina/uso terapêutico , Indução da Ovulação/métodos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/tratamento farmacológico , Gravidez , Taxa de GravidezRESUMO
BACKGROUND: Evidence from observational studies have shown that moderate intensity physical activity can reduce risk of progression and cancer-specific mortality in participants with prostate cancer. Epidemiological studies have also shown participants taking metformin to have a reduced risk of prostate cancer. However, data from randomised controlled trials supporting the use of these interventions are limited. The Prostate cancer-Exercise and Metformin Trial examines that feasibility of randomising participants diagnosed with localised or locally advanced prostate cancer to interventions that modify physical activity and blood glucose levels. The primary outcomes are randomisation rates and adherence to the interventions over 6 months. The secondary outcomes include intervention tolerability and retention rates, measures of insulin-like growth factor I, prostate-specific antigen, physical activity, symptom-reporting, and quality of life. METHODS: Participants are randomised in a 2 × 2 factorial design to both a physical activity (brisk walking or control) and a pharmacological (metformin or control) intervention. Participants perform the interventions for 6 months with final measures collected at 12 months follow-up. DISCUSSION: Our trial will determine whether participants diagnosed with localised or locally advanced prostate cancer, who are scheduled for radical treatments or being monitored for signs of cancer progression, can be randomised to a 6 months physical activity and metformin intervention. The findings from our trial will inform a larger trial powered to examine the clinical benefits of these interventions. TRIAL REGISTRATION: Prostate Cancer Exercise and Metformin Trial (Pre-EMpT) is registered on the ISRCTN registry, reference number ISRCTN13543667 . Date of registration 2nd August 2018-retrospectively registered. First participant was recruited on 11th September 2018.