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1.
J Immunother Cancer ; 11(4)2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-37028818

RESUMEN

BACKGROUND: Immune responses against tumors are subject to negative feedback regulation. Immune checkpoint inhibitors (ICIs) blocking Programmed cell death protein 1 (PD-1), a receptor expressed on T cells, or its ligand PD-L1 have significantly improved the treatment of cancer, in particular malignant melanoma. Nevertheless, responses and durability are variables, suggesting that additional critical negative feedback mechanisms exist and need to be targeted to improve therapeutic efficacy. METHODS: We used different syngeneic melanoma mouse models and performed PD-1 blockade to identify novel mechanisms of negative immune regulation. Genetic gain-of-function and loss-of-function approaches as well as small molecule inhibitor applications were used for target validation in our melanoma models. We analyzed mouse melanoma tissues from treated and untreated mice by RNA-seq, immunofluorescence and flow cytometry to detect changes in pathway activities and immune cell composition of the tumor microenvironment. We analyzed tissue sections of patients with melanoma by immunohistochemistry as well as publicly available single-cell RNA-seq data and correlated target expression with clinical responses to ICIs. RESULTS: Here, we identified 11-beta-hydroxysteroid dehydrogenase-1 (HSD11B1), an enzyme that converts inert glucocorticoids into active forms in tissues, as negative feedback mechanism in response to T cell immunotherapies. Glucocorticoids are potent suppressors of immune responses. HSD11B1 was expressed in different cellular compartments of melanomas, most notably myeloid cells but also T cells and melanoma cells. Enforced expression of HSD11B1 in mouse melanomas limited the efficacy of PD-1 blockade, whereas small molecule HSD11B1 inhibitors improved responses in a CD8+ T cell-dependent manner. Mechanistically, HSD11B1 inhibition in combination with PD-1 blockade augmented the production of interferon-γ by T cells. Interferon pathway activation correlated with sensitivity to PD-1 blockade linked to anti-proliferative effects on melanoma cells. Furthermore, high levels of HSD11B1, predominantly expressed by tumor-associated macrophages, were associated with poor responses to ICI therapy in two independent cohorts of patients with advanced melanomas analyzed by different methods (scRNA-seq, immunohistochemistry). CONCLUSION: As HSD11B1 inhibitors are in the focus of drug development for metabolic diseases, our data suggest a drug repurposing strategy combining HSD11B1 inhibitors with ICIs to improve melanoma immunotherapy. Furthermore, our work also delineated potential caveats emphasizing the need for careful patient stratification.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1 , Glucocorticoides , Inmunoterapia , Melanoma , Animales , Ratones , Linfocitos T CD8-positivos , Glucocorticoides/uso terapéutico , Interferón gamma/metabolismo , Melanoma/tratamiento farmacológico , Melanoma/patología , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Microambiente Tumoral , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/antagonistas & inhibidores , Reposicionamiento de Medicamentos
2.
J Orthop Res ; 26(12): 1562-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18634020

RESUMEN

The G-protein Galphas is involved in the physiology and pathophysiology of bone. Especially, Galphas is a key regulator of interleukin-6, which is a potent promoter of aseptic loosening. We hypothesized that the common single nucleotide polymorphism GNAS1 T393C could also affect time to aseptic loosening. Caucasian patients were genotyped for the GNAS1 T393C polymorphism. Time and median time to aseptic loosening were analyzed for dependency on GNAS1 genotypes. Time and median time were not significantly associated with genotypes. Additional analysis corrected for gender revealed, that the TT genotype was associated with significantly longer time (p = 0.048) as well as median time (p = 0.022) to aseptic loosening in female patients. In contrast to the findings in females, male TT genotype carriers had significantly shorter time (p = 0.018) and median time (p = 0.023) to aseptic loosening. Compared with TT genotype carriers heterozygous patients had a 6.25-fold lower risk with a hazard ratio of 0.160 (p = 0.016) and male patients carrying the CC genotype had an 11-fold lower risk with a hazard ratio of 0.088 (p = 0.006) in multivariate analysis. The present study suggests a significant gender-dependent role of the T393C polymorphism in aseptic loosening. The apparently contradictory results in women and men and the finding that the GNAS1 T393C genotype is an independent factor for time to aseptic loosening in male patients assigned this polymorphism as an interesting target for further investigations in bone diseases.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Prótesis de Cadera , Polimorfismo de Nucleótido Simple/genética , Falla de Prótesis , Caracteres Sexuales , Anciano , Anciano de 80 o más Años , Cromograninas , Femenino , Genotipo , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante
3.
Clin Cancer Res ; 13(19): 5790-7, 2007 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-17908970

RESUMEN

PURPOSE: Expression of the antiapoptotic and antiproliferative protein Bcl-2 has been repeatedly shown to be associated with better clinical outcome in breast cancer. We recently showed a novel regulatory (-938C>A) single-nucleotide polymorphism (SNP) in the inhibitory P2 BCL2 gene promoter generating significantly different BCL2 promoter activities. EXPERIMENTAL DESIGN: Paraffin-embedded neoplastic and nonneoplastic tissues from 274 patients (161 still alive after a follow-up period of at least 80 months) with primary unilateral invasive breast carcinoma were investigated. Bcl-2 expression of tumor cells was shown by immunohistochemistry; nonneoplastic tissues were used for genotyping. Both the Bcl-2 expression and the (-938C>A) genotypes were correlated with the patients' survival. RESULTS: Kaplan-Meier curves revealed a significant association of the AA genotype with increased survival (P = 0.030) in lymph node-negative breast cancer patients, whereas no genotype effect could be observed in lymph node-positive cases. Ten-year survival rates were 88.6% for the AA genotype, 78.4% for the AC genotype, and 65.8% for the CC genotype. Multivariable Cox regression identified the BCL2 (-938CC) genotype as an independent prognostic factor for cancer-related death in lymph node-negative breast carcinoma patients (hazard ratio, 3.59; P = 0.032). Immunohistochemical Bcl-2 expression was significantly associated with the clinical outcome of lymph node-positive but not of lymph node-negative breast cancer patients. In lymph node-negative cases, the (-938C>A) SNP was both significantly related with the immunohistochemically determined level of Bcl-2 expression (P = 0.044) and the survival of patients with Bcl-2-expressing carcinomas (P = 0.006). CONCLUSIONS: These results suggest the (-938C>A) polymorphism as a survival prognosticator as well as indicator of a high-risk group within patients with lymph node-negative breast cancer.


Asunto(s)
Genotipo , Ganglios Linfáticos/patología , Polimorfismo Genético , Proteínas Proto-Oncogénicas c-bcl-2/genética , Adulto , Anciano , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Invasividad Neoplásica , Polimorfismo de Nucleótido Simple , Riesgo , Factores de Tiempo , Resultado del Tratamiento
4.
Blood ; 109(1): 290-7, 2007 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-16960146

RESUMEN

Bcl-2 plays a key role in the regulation of apoptosis. We investigated the role of a novel regulatory single-nucleotide polymorphism (-938C>A) in the inhibitory P2 BCL2 promoter in B-cell chronic lymphocytic leukemia (B-CLL). The -938C allele displayed significantly increased BCL2 promoter activity and binding of nuclear proteins compared with the A allele. Concomitantly, Bcl-2 protein expression in B cells from CLL patients carrying the -938 AA genotype was significantly increased compared with CC genotypes. Genotype distribution between 123 CLL patients (42 AA, 55 AC, 26 CC) and 120 genotyped healthy controls (36 AA, 63 AC, 21 CC) was not significantly different, suggesting that genotypes of this polymorphism do not increase the susceptibility for B-CLL. However, median time from first diagnosis to initiation of chemotherapy and median overall survival were significantly shorter in patients with -938AA genotype (38 and 199 months, respectively) compared with AC/CC genotypes (120 and 321 months, respectively; P = .008 and P = .003, respectively). Multivariable Cox regression identified the BCL2-938AA genotype as an independent prognostic factor for the time to first treatment (hazard ratio [HR] 1.9; P = .034) together with disease stage at diagnosis (HR 2.5; P = .004) and ZAP-70 status (HR 3.0; P = .001). The BCL2-938AA genotype is associated with increased Bcl-2 expression and a novel unfavorable genetic marker in patients with B-CLL.


Asunto(s)
Biomarcadores de Tumor/genética , Genes bcl-2 , Leucemia Linfocítica Crónica de Células B/genética , Proteínas de Neoplasias/genética , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/genética , Anciano , Alelos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Línea Celular , Aberraciones Cromosómicas , Cromosomas Humanos/genética , Cromosomas Humanos/ultraestructura , Progresión de la Enfermedad , Femenino , Genotipo , Humanos , Estimación de Kaplan-Meier , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Análisis de Supervivencia , Transcripción Genética , Transfección , Proteína Tirosina Quinasa ZAP-70/análisis
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