RESUMO
Signal transducers and activators of transcription 3 (STAT3) signaling is persistently activated and could contribute to tumorigenesis of medulloblastoma. Numerous studies have demonstrated that inhibition of the persistent STAT3 signaling pathway results in decreased proliferation and increased apoptosis in human cancer cells, indicating that STAT3 is a viable molecular target for cancer therapy. In this study, we investigated a novel non-peptide, cell-permeable small molecule, named LY5, to target STAT3 in medulloblastoma cells. LY5 inhibited persistent STAT3 phosphorylation and induced apoptosis in human medulloblastoma cell lines expressing constitutive STAT3 phosphorylation. The inhibition of STAT3 signaling by LY5 was confirmed by down-regulating the expression of the downstream targets of STAT3, including cyclin D1, bcl-XL, survivin, and micro-RNA-21. LY5 also inhibited the induction of STAT3 phosphorylation by interleukin-6 (IL-6), insulin-like growth factor (IGF)-1, IGF-2, and leukemia inhibitory factor in medulloblastoma cells, but did not inhibit STAT1 and STAT5 phosphorylation stimulated by interferon-γ (IFN-γ) and EGF, respectively. In addition, LY5 blocked the STAT3 nuclear localization induced by IL-6, but did not block STAT1 and STAT5 nuclear translocation mediated by IFN-γ and EGF, respectively. A combination of LY5 with cisplatin or x-ray radiation also showed more potent effects than single treatment alone in the inhibition of cell viability in human medulloblastoma cells. Furthermore, LY5 demonstrated a potent inhibitory activity on cell migration and angiogenesis. Taken together, these findings indicate LY5 inhibits persistent and inducible STAT3 phosphorylation and suggest that LY5 is a promising therapeutic drug candidate for medulloblastoma by inhibiting persistent STAT3 signaling.
Assuntos
Aminopiridinas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Fator de Transcrição STAT3/antagonistas & inibidores , Sulfonamidas/farmacologia , Transporte Ativo do Núcleo Celular , Aminopiridinas/síntese química , Aminopiridinas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Sobrevivência Celular , Cisplatino/farmacologia , Ciclina D/genética , Ciclina D/metabolismo , Citocinas/farmacologia , Regulação para Baixo , Células Endoteliais da Veia Umbilical Humana , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Meduloblastoma/metabolismo , MicroRNAs/genética , Fosforilação , Transdução de Sinais , Sulfonamidas/síntese química , Sulfonamidas/química , Survivina , Proteína bcl-X/genética , Proteína bcl-X/metabolismoRESUMO
UNLABELLED: c-Myc is a well-known oncogene frequently up-regulated in different malignancies, whereas liver-specific microRNA (miR)-122, a bona fide tumor suppressor, is down-regulated in hepatocellular cancer (HCC). Here we explored the underlying mechanism of reciprocal regulation of these two genes. Real-time reverse-transcription polymerase chain reaction (RT-PCR) and northern blot analysis demonstrated reduced expression of the primary, precursor, and mature miR-122 in c-MYC-induced HCCs compared to the benign livers, indicating transcriptional suppression of miR-122 upon MYC overexpression. Indeed, chromatin immunoprecipitation (ChIP) assay showed significantly reduced association of RNA polymerase II and histone H3K9Ac, markers of active chromatin, with the miR-122 promoter in tumors relative to the c-MYC-uninduced livers, indicating transcriptional repression of miR-122 in c-MYC-overexpressing tumors. The ChIP assay also demonstrated a significant increase in c-Myc association with the miR-122 promoter region that harbors a conserved noncanonical c-Myc binding site in tumors compared to the livers. Ectopic expression and knockdown studies showed that c-Myc indeed suppresses expression of primary and mature miR-122 in hepatic cells. Additionally, Hnf-3ß, a liver enriched transcription factor that activates miR-122 gene, was suppressed in c-MYC-induced tumors. Notably, miR-122 also repressed c-Myc transcription by targeting transcriptional activator E2f1 and coactivator Tfdp2, as evident from ectopic expression and knockdown studies and luciferase reporter assays in mouse and human hepatic cells. CONCLUSION: c-Myc represses miR-122 gene expression by associating with its promoter and by down-regulating Hnf-3ß expression, whereas miR-122 indirectly inhibits c-Myc transcription by targeting Tfdp2 and E2f1. In essence, these results suggest a double-negative feedback loop between a tumor suppressor (miR-122) and an oncogene (c-Myc).
Assuntos
Carcinoma Hepatocelular/fisiopatologia , Proteínas de Ligação a DNA/fisiologia , Fator de Transcrição E2F1/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Hepáticas/fisiopatologia , MicroRNAs/fisiologia , Proteínas Proto-Oncogênicas c-myc/fisiologia , Fatores de Transcrição/fisiologia , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Regulação para Baixo/genética , Regulação para Baixo/fisiologia , Fator de Transcrição E2F1/genética , Regulação Neoplásica da Expressão Gênica/genética , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-myc/genética , Fatores de Transcrição/genética , Regulação para Cima/genética , Regulação para Cima/fisiologiaRESUMO
BACKGROUND: Medulloblastoma is the most common type of pediatric brain tumor. Although numerous factors influence patient survival rates, more than 30% of all cases will ultimately be refractory to conventional therapies. Current standards of care are also associated with significant morbidities, giving impetus for the development of new treatments. We have previously shown that oncolytic measles virotherapy is effective against medulloblastoma, leading to significant prolongation of survival and even cures in mouse xenograft models of localized and metastatic disease. Because medulloblastomas are known to be highly vascularized tumors, we reasoned that the addition of angiogenesis inhibitors could further enhance the efficacy of oncolytic measles virotherapy. Toward this end, we have engineered an oncolytic measles virus that express a fusion protein of endostatin and angiostatin, two endogenous and potent inhibitors of angiogenesis. METHODS: Oncolytic measles viruses encoding human and mouse variants of a secretable endostatin/angiostatin fusion protein were designed and rescued according to established protocols. These viruses, known as MV-hE:A and MV-mE:A respectively, were then evaluated for their anti-angiogenic potential and efficacy against medulloblastoma cell lines and orthotopic mouse models of localized disease. RESULTS: Medulloblastoma cells infected by MV-E:A readily secrete endostatin and angiostatin prior to lysis. The inclusion of the endostatin/angiostatin gene did not negatively impact the measles virus' cytotoxicity against medulloblastoma cells or alter its growth kinetics. Conditioned media obtained from these infected cells was capable of inhibiting multiple angiogenic factors in vitro, significantly reducing endothelial cell tube formation, viability and migration compared to conditioned media derived from cells infected by a control measles virus. Mice that were given a single intratumoral injection of MV-E:A likewise showed reduced numbers of tumor-associated blood vessels and a trend for increased survival compared to mice treated with the control virus. CONCLUSIONS: These data suggest that oncolytic measles viruses encoding anti-angiogenic proteins may have therapeutic benefit against medulloblastoma and support ongoing efforts to target angiogenesis in medulloblastoma.
Assuntos
Inibidores da Angiogênese/uso terapêutico , Angiostatinas/antagonistas & inibidores , Endostatinas/antagonistas & inibidores , Vírus do Sarampo/fisiologia , Meduloblastoma/terapia , Terapia Viral Oncolítica/efeitos adversos , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Vírus do Sarampo/genética , Meduloblastoma/patologia , Camundongos , Neoplasias Experimentais , Vírus Oncolíticos/genética , Células Vero , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Cytokines are known as important regulators of the entire gamut of cancer from initiation, invasion and metastasis. This fact and plethora of gene polymorphism data prompted us to investigate cytokine gene polymorphisms in breast cancer (BC) patients. METHODS: Selected polymorphisms in the IL-1ß [-511 T>C (rs16944) and +3954 C>T (rs1143634)]; IL-6 [-174 G>C (rs1800795)]; IL-10 [-1082 A>G (rs1800896), -819 T>C (rs1800871) and -592 A>C (rs1800872)] genes were genotyped in 200 BC patients and 200 healthy volunteers in a case-control study using PCR-RFLP and direct DNA sequencing techniques. Peripheral cytokine levels were measured using ELISA. Allele and genotype data were analyzed for significance of differences between cases and controls using Chi-Square [χ(2)] test. Two sided P-values of less than 0.05 were considered to be statistically significant. RESULTS: Peripheral level of all three cytokines did not show any significant difference between cases and controls. Allele and genotype frequency of IL-1ß [-511 T>C (rs16944)] did not show any difference between cases and controls. On the other hand mutant allele and genotype at IL-1ß [+3954 C>T (rs1143634)] associated with increased risk of BC. This was also true for pre-menopausal cases and for mutant genotype in post-menopausal cases. Mutant allele and genotypes at IL-6 [-174 G>C (rs1800795)] appeared to be protective in nature such that controls had a higher frequency of both mutant alleles and genotypes. None of the three SNPs in IL-10 gene associated with risk of BC, except significant association of mutant allele and genotypes of -1082 A>G (rs1800896) polymorphism with postmenopausal BC. CONCLUSIONS: Mutant allele and genotype at IL-1ß [+3954 C>T (rs1143634)] site associated with increased BC risk, while mutant allele and genotypes at IL-6 [-174 G>C (rs1800795)] polymorphism appeared to be protective. Also, there was significant association of mutant allele and genotypes of IL-10 [-1082 A>G (rs1800896)] with postmenopausal BC. None of the other polymorphisms investigated appear to affect BC risk.
Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença/genética , Interleucina-10/genética , Interleucina-1beta/genética , Interleucina-6/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Neoplasias da Mama/sangue , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Frequência do Gene , Genótipo , Humanos , Interleucina-10/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores de Risco , Adulto JovemRESUMO
In this first report on the association of an IL-10 promoter polymorphism with type 2 diabetes mellitus in a North Indian population, the -592A/C SNP (rs1800872) was genotyped by PCR-RFLP and the IL-10 level measured using ELISA. Although no significant difference was observed in the genotypic frequencies (P = 0.657), diabetes patients carried a significantly higher number of A alleles at the -592 position, 25.6% (P < 0.001, odds ratio 0.887, 95% CI 0.670-1.184). Significant correlations were detected in postprandial glucose levels of CC-genotype patients and controls (P = 0.025), age and waist-hip ratio of CA patients and controls (P ≤ 0.001), and fasting glucose (P = 0.045) and low-density lipoprotein (P = 0.049) in all patients and controls. The serum IL-10 level was significantly higher in patients than in controls (P = 0.033). The polymorphism was significantly associated with disease incidence and its biochemical manifestations.
Assuntos
Diabetes Mellitus Tipo 2/genética , Interleucina-10/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , População Branca/genética , Adulto , Sequência de Bases , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/sangue , Feminino , Genótipo , Humanos , Índia , Interleucina-10/sangue , Masculino , Pessoa de Meia-Idade , Dados de Sequência MolecularRESUMO
Rhabdomyosarcoma (RMS) is an aggressive pediatric tumor with a poor prognosis for metastasis and recurrent disease. Large-scale sequencing endeavors demonstrate that Rhabdomyosarcomas have a dearth of precisely targetable driver mutations. However, IGF-2 signaling is known to be grossly altered in RMS. The insulin receptor (IR) exists in two alternatively spliced isoforms, IR-A and IR-B. The IGF-2 signaling molecule binds both its innate IGF-1 receptor as well as the insulin receptor variant A (IR-A) with high affinity. Mitogenic and proliferative signaling via the canonical IGF-2 pathway is, therefore, augmented by IR-A. This study shows that RMS patients express increased IR-A levels compared to control tissues that predominantly express the IR-B isoform. We also found that Hif-1α is significantly increased in RMS tumors, portraying their hypoxic phenotype. Concordantly, the alternative splicing of IR adapts to produce more IR-A in response to hypoxic stress. Upon examining the pre-mRNA structure of the gene, we identified a potential hypoxia-responsive element, which is also the binding site for the RNA-binding protein CUG-BP1 (CELF1). We designed Splice Switching Oligonucleotides (SSO) against this binding site to decrease IR-A levels in RMS cell lines and, consequently, rescue the IR-B expression levels. SSO treatment resulted in a significant reduction in cell proliferation, migration, and angiogenesis. Our data shows promising insight into how impeding the IGF-2 pathway by reducing IR-A expression mitigates tumor growth. It is evident that Rhabdomyosarcomas use IR alternative splicing as yet another survival strategy that can be exploited as a therapeutic intervention in conjunction with already established anti-IGF-1 receptor therapies.
RESUMO
TNF-α and -ß, the multi-functional pro-inflammatory cytokines, are known to play important roles in both tumor progression and destruction based on their concentrations. Growth factors and various stimuli such as cytokines regulate proliferation of the breast epithelial cells. Therefore, the polymorphisms in the genes encoding these signaling molecules could affect the risk of breast cancer. We have investigated selected genetic polymorphisms in TNF-α promoter (rs1800629, -308 G>A and rs361525, -238 G>A) and TNF-ß intron 1 (rs909253, +252 A>G) in ethnically two different case-control groups from India. The study included 200 cases and 200 controls from an Indo-European (North Indian) group, and 265 cases and 237 controls from a Dravidian (South Indian) group. Genotyping of a total of 902 individuals was done by direct DNA sequencing. None of the polymorphisms showed significant association with breast cancer in the Indo-European group; however, all the three polymorphisms showed strong association with breast cancer in the Dravidian group. Further, sub-group analysis in the Indo-European group showed no significant difference between pre-menopausal cases and controls or between post-menopausal cases and controls at any of the loci analyzed. However, all the polymorphisms in the Dravidian group were significantly associated with pre-menopausal but not with post-menopausal breast cancer. In conclusion, TNF-α and -ß polymorphisms are strongly associated with breast cancer in the Dravidian but not in the Indo-European group.
Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/genética , Variação Genética , Linfotoxina-alfa/genética , Polimorfismo Genético , Fator de Necrose Tumoral alfa/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/metabolismo , Estudos de Casos e Controles , Etnicidade , Feminino , Genótipo , Humanos , Índia , Menopausa , Pessoa de Meia-Idade , RiscoRESUMO
BACKGROUND & OBJECTIVES: The greater tendency to diabetes in Indians may be due to genetic factors in addition to environment and diet. CD36, a class B scavenger cell surface receptor mediates internalization of oxidized low density lipoprotein (Ox-LDL) leading to the formation of macrophage foam cells. CD36 deficiency is related to phenotypic expression of the metabolic syndrome, frequently associated with atherosclerotic cardiovascular diseases resulting in raised levels of glucose thereby contributing to type 2 diabetes (T2DM). Therefore, the association of human CD36 gene mutation to T2DM needs investigation. We undertook this study to investigate CD36 gene status in north Indian subjects by screening for the deletion of exons 3, 4 and 5 and certain polymorphisms. METHODS: Clinical characteristics were compared between 300 T2DM patients and 100 healthy controls. Deletion analysis was carried out for exons 3, 4 and 5 of CD36 gene in 300 T2DM patients using PCR and agarose gel electrophoresis. Genotype analysis for two polymorphisms 478C>T and delAC in exons 4 and 5 respectively was carried out using PCR-RFLP method. RESULTS: Biochemical parameters such as fasting and post-prandial glucose levels, total cholesterol, LDL-cholesterol and blood pressure were slightly raised in the T2DM patients when compared with controls with lowered HDL-cholesterol. No exonic deletion was observed in the 300 patients and 100 controls screened. All individuals were found to be homozygous (CC and -/-) for the two polymorphisms studied. INTERPRETATION & CONCLUSIONS: Although no exonic deletion was found in T2DM patients, our study suggests that all 15 exons need to be screened for mutations which lead to CD36 deficiency. Genotyping studies of the two SNPs in the CD36 gene confirmed the absence of exons 4 and 5 deletion. This is perhaps the first report from India suggesting that CD36 is one of the several important genes that need to be explored in relation to T2DM.
Assuntos
Antígenos CD36/genética , Diabetes Mellitus Tipo 2/genética , Adulto , Glicemia/análise , Pressão Sanguínea , LDL-Colesterol/sangue , Éxons , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Deleção de SequênciaRESUMO
A small library of novel benzocoumarin derivatives based on naturally occurring neo-tanshinlactone scaffold was constructed and their antiproliferative activities against breast cancer cells MCF-7 and MDA-MB-231 were evaluated. A number of derivatives showed good anti-breast cancer activity, in some cases higher to that of the reference compound tamoxifen. In particular, benzocoumarins Bc-5, Bc-8 and Bc-9 strongly inhibited the proliferation of MCF-7 cancer cell line with the IC(50) values of 3.8, 7.9 and 6.5 µM, respectively. The compounds were capable of inducing nuclear fragmentation, cell cycle arrest and caspase dependent apoptosis in MCF-7 cell lines. In addition, these derivatives were devoid of cytotoxic effect against normal osteoblast cells. These synthetic benzocoumarins hold promises for developing safer alternative to the existing anti-breast cancer agents.
Assuntos
Antineoplásicos/síntese química , Neoplasias da Mama/tratamento farmacológico , Cumarínicos/química , Cumarínicos/farmacologia , Furanos/química , Pironas/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Bibliotecas de Moléculas PequenasRESUMO
A series of new benzoxazepine derivatives substituted with different alkoxy and aryloxy group were synthesized comprising synthetic steps of Mitsunobu reaction, lithium aluminum hydride (LAH) reduction, followed by debenzylation and finally intramolecular Mitsunobu cyclization. The new benzoxazepines specifically inhibited growth of breast cancer cell lines, MCF-7 and MDA-MB-231, but lack cytotoxicity to normal HEK-293 cells. The cell growth inhibition induced by the active compounds was due to cell cycle arrest at G(0)/G(1) phase. The active compound could cause significant reduction in tumor volume of MCF-7 xenograft tumor in nude mice model and their activity was comparable to that of tamoxifen citrate at 16mgkg(-1) dose at 30days of treatment. The identified most active compounds of the series have specific advantages as anti-cancer agent in breast cancer than tamoxifen.
Assuntos
Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Oxazepinas/química , Compostos de Alumínio/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Ciclização , Feminino , Fase G1 , Humanos , Compostos de Lítio/química , Camundongos , Camundongos Nus , Oxazepinas/síntese química , Oxazepinas/uso terapêutico , Fase de Repouso do Ciclo Celular , Relação Estrutura-Atividade , Tamoxifeno/uso terapêutico , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Interleukins and cytokines are important regulator of the aetio-pathogenesis of the majority of cancers. Mechanistic role of IL-1RN and IL-4, particularly in breast carcinogenesis, is well documented. However, the role of polymorphisms of IL-1RN and IL-4 combinations associated with risk of breast cancer is not reported. The IL-1RN and IL-4 gene polymorphisms were genotyped with VNTR-PCR in 100 patients (benign tumor n = 32 and breast cancer n = 68) and 200 normal healthy control subjects with normal mammogram. Genotype distribution and allelic frequencies between patients and controls were compared and odds ratios (OR) with 95% confidence intervals (CI) were calculated using SPSS software (version 12.0). There were no significant differences in the genotype distributions of both IL-1RN and IL-4 polymorphisms between cases and controls. Similarly, subgroup analysis showed that there is no significant association for pre- and postmenopausal women. However, BB genotype of IL-1RN significantly differs among benign and malignant stages of breast cancer. IL-1RN and IL-4 polymorphisms alone or in combination are not associated with risk of breast cancer in Indian patients. The association of IL-1RN with malignant stages may indicate its possible role in progression of breast cancer. Further studies in other population are needed to confirm our findings and to elucidate the role of IL-1RN in progression of breast cancer.
Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Interleucina-1/genética , Interleucina-4/genética , Polimorfismo Genético , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Índia , Pessoa de Meia-Idade , Pós-Menopausa/genética , Pré-Menopausa/genética , Fatores de RiscoRESUMO
A series of 3,4,6-triaryl-2-pyranones, new class of anti-breast cancer agents, have been synthesized as a structural variants of cyclic triphenylethylenes by replacing the fused benzene ring with pendant phenyl ring to mimic the phenolic A ring of estradiol. Nine of these newly synthesized pyranones exhibited significant anti-proliferative activity in both ER+ve and ER-ve breast cancer cell lines. Four active non-cytotoxic compounds 5c, 5d, 5g and 5h showed specific and selective cytotoxicity and two compounds 5d and 5h induced significant DNA fragmentation in both MCF-7 and MDA-MB-231 cell lines. Based on RBA studies, the molecules probably act in an ER-independent mechanism. The involved pathway was observed as caspase-dependant apoptosis in MCF-7 cells. However, the particular caspases involved and the possible cellular target through which this series of compounds mediate cell death are not known.
Assuntos
Antineoplásicos/farmacologia , Pironas/química , Pironas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Modelos Moleculares , Estrutura Molecular , Piperidinas/química , Pirrolidinas/químicaRESUMO
BACKGROUND: The vitamin D receptor (VDR) gene is a candidate gene for susceptibility to several diseases. Studies on association between VDR polymorphisms and risk of type 2 diabetes (T2DM) in different ethnic populations are yet inconclusive. AIMS: This study was conducted to evaluate association between VDR polymorphisms and genetic susceptibility to T2DM in the north Indian population. SETTINGS AND DESIGN: One hundred clinically diagnosed T2DM patients and 160 healthy controls from the north Indian population were recruited for genetic association study. MATERIALS AND METHODS: Genomic DNA was extracted from blood and genotyped for the single nucleotide polymorphism SNPs of FokI (T/C) [rs2228570], BsmI (A/G) [rs1544410] and TaqI (C/T) [rs731236] by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis. STATISTICAL ANALYSIS USED: Genotype distribution and allelic frequencies were compared between patients and controls. Mean values and odds ratios (ORs) with 95% confidence interval (CI) were calculated using SPSS software (version 15.0). RESULTS: The genotype distribution, allele and haplotype frequencies of VDR polymorphism did not differ significantly between patients and controls. Mean age and waist-hip ratio of patients were found to be associated with VDR polymorphism. Combination studies showed FFBbtt increased the risk of T2DM in north Indians. CONCLUSIONS: Our data suggest that VDR gene polymorphism in combination of genotypes is associated with the risk of T2DM and thus requires further studies as a probable genetic risk marker for T2DM.
Assuntos
Diabetes Mellitus Tipo 2/genética , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Índia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de RestriçãoRESUMO
BACKGROUND: Inflammation is a key event closely associated with the pathophysiology of type 2 diabetes mellitus (T2DM). Association of genetic polymorphisms of inflammatory cytokines with T2DM is largely unknown. Our objective was to investigate the relationship of polymorphism of IL-1RN and IL-4, two important biomarkers of inflammation, with the risk of T2DM. SETTING AND DESIGN: We recruited 120 clinically diagnosed T2DM patients and 150 normal healthy controls for this study in order to evaluate the nature of polymorphisms of IL-1RN and IL-4. MATERIALS AND METHODS: Genomic DNA was isolated from the blood of all subjects, and the variable number of tandem repeat (VNTR) polymorphisms of IL-1RN and IL-4 genes was identified by polymerase chain reaction. STATISTICAL ANALYSIS USED: Genotype distribution and allelic frequencies were compared between patients and control group. Means, as well as odds ratios (ORs) with 95% confidence intervals (CI), were calculated using SPSS software (version 11.5). RESULTS: Our study revealed that distribution of both IL-4 and IL-1RN (VNTR) gene polymorphisms were significantly associated with T2DM subjects. We, however, failed to find any association of gene-gene (IL-4 and IL-1RN) interaction with T2DM. CONCLUSIONS: Both IL-4 and IL-1RN (VNTR) gene polymorphisms were significantly associated with T2DM subjects. This may suggest that the genetic polymorphisms of IL-4 and IL-1RN genes could serve as susceptibility indicators for T2DM in the Indian population, but the actual mechanism of these associations will require more elaborate investigations. Lack of association of gene-gene (IL-4 and IL-1RN) interaction with T2DM may indicate the independent nature of influence of both these genes on the risk of T2DM.
Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-4/genética , Polimorfismo Genético , Alelos , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Marcadores Genéticos , Genótipo , Humanos , Índia/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da PolimeraseRESUMO
Interleukins-6 (IL-6)/GP130 signaling pathway represents a promising target for cancer therapy due to its critical role in survival and progression of multiple types of cancer. We have identified Bazedoxifene, a Food and Drug Administration (FDA)-approved drug used for the prevention of postmenopausal osteoporosis, with novel function as inhibitor of IL-6/GP130 interaction. In this study, we investigate the effect of Bazedoxifene in rhabdomyosarcoma and evaluate whether inhibiting IL-6/GP130 signaling is an effective therapeutic strategy for rhabdomyosarcoma. The inhibitory effect of Bazedoxifene was assessed in rhabdomyosarcoma cell lines in vitro and RH30 xenograft model was used to further examine the suppressive efficacy of Bazedoxifene on tumor growth in vivo. Rhabdomyosarcoma cells showed their sensitivity to GP130 inhibition using gene knockdown or neutralized antibody, suggesting IL-6/GP130 as therapeutic target in rhabdomyosarcoma cells. Bazedoxifene decreased the signal transducer and activator of transcription3 (STAT3) phosphorylation, blocked STAT3 DNA binding, and down-regulated the expression of STAT3 downstream genes. Bazedoxifene also induced cell apoptosis, reduced cell viability, and inhibited colony formation in rhabdomyosarcoma cells. The inhibition of colony formation, STAT3 phosphorylation, or cell viability following Bazedoxifene treatment was partially reversed by addition of excess IL-6 or overexpression of constitutive STAT3, respectively, supporting Bazedoxifene acted through IL-6/GP130 signaling. In addition, Bazedoxifene repressed cell invasion and angiogenesis in vitro. Furthermore, oral administration of Bazedoxifene significantly suppressed tumor growth and expression of STAT3 phosphorylation in nude mice bearing established human rhabdomyosarcoma xenograft. Taken together, these findings validate IL-6/GP130 signaling as therapeutic target in rhabdomyosarcoma and provide first evidence that Bazedoxifene may serve as a novel promising drug targeting IL-6/GP130 for treatment of rhabdomyosarcoma.
Assuntos
Receptor gp130 de Citocina/metabolismo , Indóis/farmacologia , Interleucina-6/metabolismo , Rabdomiossarcoma/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rabdomiossarcoma/metabolismo , Rabdomiossarcoma/patologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Leiomyosarcoma (LMS) is a malignant soft tissue sarcoma (STS) with a dismal prognosis following metastatic disease. Chemotherapeutic intervention has demonstrated to have modest clinical efficacy with no curative potential in LMS patients. Previously, we demonstrated pan-HDAC inhibition to have a superior effect in various complex karyotypic sarcomas. In this study, our goal is to evaluate the therapeutic efficacy of mocetinostat alone and in combination with gemcitabine in LMS. Human leiomyosarcoma (LMS) cell lines were used for in vitro and in vivo studies. Compounds tested included the class I HDAC inhibitor, mocetinostat, and nucleoside analog, gemcitabine. MTS and clonogenic assays were used to evaluate the effect of mocetinostat on LMS cell growth. Cleaved caspase 3/7 analysis was used to determine the effects of mocetinostat on apoptosis. Compusyn software was used to determine in vitro synergy studies for the combination of mocetinostat plus gemcitabine. A LMS xenograft model in SCID mice was used to test the impact of mocetinostat alone, gemcitabine alone and the combination of mocetinostat plus gemcitabine. Mocetinostat abrogated LMS cell growth and clonogenic potential, and enhanced apoptosis in LMS cell lines. The combination of mocetinostat plus gemcitabine exhibited a synergistic effect in LMS cells in vitro. Similarly, mocetinostat combined with gemcitabine resulted in superior anti-LMS effects in vivo. Mocetinostat reduced the expression of gemcitabine-resistance markers RRM1, RRM2, and increased the expression of gemcitabine-sensitivity marker, hENT1, in LMS cells. LMS are aggressive, metastatic tumors with poor prognosis where effective therapeutic interventions are wanting. Our studies demonstrate the potential utility of mocetinostat combined with gemcitabine for the treatment of LMS.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leiomiossarcoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Benzamidas/administração & dosagem , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Sinergismo Farmacológico , Humanos , Leiomiossarcoma/patologia , Pirimidinas/administração & dosagem , GencitabinaRESUMO
Although activation of the STAT3 pathway has been associated with tumor progression in a wide variety of cancer types (including ovarian cancer), the precise mechanism of invasion and metastasis due to STAT3 are not fully delineated in ovarian cancer. We found that pSTAT3 Tyr705 is constitutively activated in patient ascites and ascites-derived ovarian cancer cells (ADOCCs), and the range of STAT3 expression could be very high to low. In vivo transplantation of ADOCCs with high pSTAT3 expression into the ovarian bursa of mice resulted in a large primary tumor and widespread peritoneal metastases. In contrast, ADOCCs with low STAT3 expression or ADOCCs with STAT3 expression knockdown, led to reduced tumor growth and an absence of metastases in vivo. Cytokines derived from the ADOCC culture medium activate the interleukin (IL)-6/STAT pathway in the STAT3 knockout (KO) cells, compensating for the absence of inherent STAT3 in the cells. Treatment with HO-3867 (a novel STAT3 inhibitor at 100 p.p.m. in an orthotopic murine model) significantly suppressed ovarian tumor growth, angiogenesis and metastasis by targeting STAT3 and its downstream proteins. HO-3867 was found to have cytotoxic effects in ex vivo cultures of freshly collected human ovarian cancers, including those resistant to platinum-based chemotherapy. Our results show that STAT3 is necessary for ovarian tumor progression/metastasis and highlight the potential for targeting STAT3 by HO-3867 as a therapeutic strategy for ovarian cancer.
Assuntos
Ascite/patologia , Neoplasias Ovarianas/patologia , Fator de Transcrição STAT3/metabolismo , Regulação para Cima , Animais , Ascite/metabolismo , Movimento Celular , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , Humanos , Camundongos , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Piperidonas/administração & dosagem , Piperidonas/farmacologia , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Cytokines are known to be important mediators during renal graft outcome. The present study was therefore, conducted to determine the impact of IL-1beta and its receptor antagonist polymorphism on allograft outcome. We evaluated single nucleotide polymorphism (SNPs) in interleukin-1 gene cluster, IL-1beta (promoter region -511 and exon-5 +3954) and IL-1Ra (86-bp VNTR) in 136 renal transplant recipients and 150 normal healthy controls by polymerase chain restriction based (PCR-RFLP) analysis. Recipients were HLA matched and clinically characterized including delayed graft function (DGF), rejection episode (RE) and stable graft function (SGF). Haplotypes and linkage disequilibrium (LD) were determined using SNPAnalyzer software. Significant difference was observed for the frequency distribution of the three sites of IL-1 gene among patients and controls (p<0.001, 0.022 and <0.001 respectively). When RE and DGF were compared to SGF, only IL-1Ra showed significant differences among RE and SGF (p=0.014) and DGF and SGF (p=0.020). The presence of 1/2 genotype showed 18 folds risk in RE and 10 folds in DGF (OR=18.000 and OR=10.667 respectively). The majority of recipients with SGF had 1-4 HLA mismatch whereas RE had 5-8 mismatches. Risk for rejection increased >6 folds (OR=6.571; p<0.01) for 5-8 mismatches. Haplotypes constructed with the combination of three polymorphisms in IL-1 gene cluster showed significant difference between RE and SGF group. LD value for IL-1beta (promoter region) and IL-1Ra and IL-1beta promoter and exon-5 gene in the control group indicated strong association among the variants (D'=0.37, p<0.0001 and D'=0.29, p=0.002). Our study demonstrate that genetically determined low production of IL-1Ra may be a risk factor for RE and DGF and that IL-1beta/IL-1Ra haplotype influences the impact of allograft outcome. These findings may significantly abet in better perception of the survival of the graft.
Assuntos
Função Retardada do Enxerto/genética , Rejeição de Enxerto/genética , Sobrevivência de Enxerto/genética , Interleucina-1/genética , Transplante de Rim , Polimorfismo Genético , Sialoglicoproteínas/genética , Adolescente , Adulto , Feminino , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Haplótipos , Teste de Histocompatibilidade , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites/genéticaRESUMO
UNLABELLED: Epithelioid sarcoma is a rare neoplasm uniquely comprised of cells exhibiting both mesenchymal and epithelial features. Having propensity for local and distant recurrence, it poses a diagnostic dilemma secondary to pathologic complexity. Patients have dismal prognosis due to lack of effective therapy. HDAC inhibitors (HDACi) exhibit marked antitumor effects in various malignancies. The studies here demonstrate that pan-HDAC inhibitors constitute novel therapeutics versus epithelioid sarcoma. Human ES cells (VAESBJ, HS-ES, Epi-544) were studied in preclinical models to evaluate HDACi effects. Immunoblot and RT-PCR were used to evaluate expression of acetylated tubulin, histones H3/H4, EZH2 upon HDACi. MTS and clonogenic assays were used to assess the impact of HDACi on cell growth. Cell culture assays were used to evaluate the impact of HDACi and EZH2-specific siRNA inhibition on cell-cycle progression and survival. Unbiased gene array analysis was used to identify the impact of HDACi on epithelioid sarcoma gene expression. Xenografts were used to evaluate epithelioid sarcoma tumor growth in response to HDACi. HDAC inhibition increased target protein acetylation and abrogated cell growth and colony formation in epithelioid sarcoma cells. HDACi induced G(2) cell-cycle arrest and marked apoptosis, and reduced tumor growth in xenograft models. HDACi induced widespread gene expression changes, and EZH2 was significantly downregulated. EZH2 knockdown resulted in abrogated cell growth in vitro. IMPLICATIONS: The current study suggests a clinical role for HDACi in human epithelioid sarcoma, which, when combined with EZH2 inhibitors, could serve as a novel therapeutic strategy for epithelioid sarcoma patients. Future investigations targeting specific HDAC isoforms along with EZH2 may potentially maximizing treatment efficacy.
Assuntos
Antineoplásicos/administração & dosagem , Epigênese Genética/efeitos dos fármacos , Inibidores de Histona Desacetilases/administração & dosagem , Sarcoma/tratamento farmacológico , Sarcoma/genética , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histonas/genética , Histonas/metabolismo , Humanos , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND AND PURPOSE: Formation of kidney stones is still not understood but is hypothesized to be associated with the vitamin D receptor gene (VDR). In order to assess the eventual role of VDR start-codon FokI polymorphism in stone formation, we evaluated the association between calcium stone disease and this polymorphism in a North Indian population. PATIENTS AND METHODS: A control group comprised of 166 healthy individuals (age range 22-58 years) and a group of 138 patients with calcium oxalate stones (age range 21-72 years) were examined. The polymorphism was detected using polymerase chain reaction-based restriction analysis. An unexcisable length of 265 bp (CC) and two fragments of 169 bp and 96 bp (TT) were obtained by FokI restriction digestion. RESULTS: There was a statistically significant difference between the control and patient groups (X2 test, P<0.001) for the genotype of the VDR FokI start-codon polymorphism. The odds ratio (with 95% CI) for the C allele in those at risk of stone disease was 1.654 (1.041, 2.628). The VDR frequency distribution was also statistically significant (P<0.001) in case of male sex. The frequency distribution for this genetic polymorphism was not statistically different in normocalciuric and hypercalciuric stone patients (P=0.355). CONCLUSION: The VDR FokI polymorphism may be a good candidate for a marker for calcium oxalate-stone disease. These findings may contribute a small piece to the understanding of the pathogenesis of urinary calculi.