RESUMO
BACKGROUND: Tumor-associated macrophages (TAMs) constitute a major portion of the leukocyte infiltrate found in breast cancer (BC). BC cells may reprogram TAMs in a pro-angiogenic and immunosuppressive sense. We previously showed that high expression of the ID4 protein in triple-negative BC cells leads to the induction of a proangiogenic program in TAMs also through the downregulation of miR-107. Here, we investigated the expression and function of the ID4 protein in TAMs. METHODS: Human macrophages obtained from peripheral blood-derived monocytes (PBDM) and mouse RAW264.7 cells were used as macrophage experimental systems. ID4-correlated mRNAs of the TCGA and E-GEOD-18295 datasets were analyzed. RESULTS: We observed that BC cells determine a paracrine induction of ID4 expression and activation of the ID4 promoter in neighboring macrophages. Interestingly, ID4 expression is higher in macrophages associated with invasive tumor cells compared to general TAMs, and ID4-correlated mRNAs are involved in various pathways that were previously reported as relevant for TAM functions. Selective depletion of ID4 expression in macrophages enabled validation of the ability of ID4 to control the expression of YAP1 and of its downstream targets CTGF and CYR61. CONCLUSION: Collectively, our results show that activation of ID4 expression in TAMs is observed as a consequence of BC cell paracrine activity and could participate in macrophage reprogramming in BC.
Assuntos
Neoplasias da Mama/genética , Fator de Crescimento do Tecido Conjuntivo/genética , Proteína Rica em Cisteína 61/genética , Proteínas Inibidoras de Diferenciação/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Comunicação Parácrina/genética , Fatores de Transcrição/genética , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Proteínas de Sinalização YAPRESUMO
BACKGROUND: As crucial regulators of the immune response against pathogens, macrophages have been extensively shown also to be important players in several diseases, including cancer. Specifically, breast cancer macrophages tightly control the angiogenic switch and progression to malignancy. ID4, a member of the ID (inhibitors of differentiation) family of proteins, is associated with a stem-like phenotype and poor prognosis in basal-like breast cancer. Moreover, ID4 favours angiogenesis by enhancing the expression of pro-angiogenic cytokines interleukin-8, CXCL1 and vascular endothelial growth factor. In the present study, we investigated whether ID4 protein exerts its pro-angiogenic function while also modulating the activity of tumour-associated macrophages in breast cancer. METHODS: We performed IHC analysis of ID4 protein and macrophage marker CD68 in a triple-negative breast cancer series. Next, we used cell migration assays to evaluate the effect of ID4 expression modulation in breast cancer cells on the motility of co-cultured macrophages. The analysis of breast cancer gene expression data repositories allowed us to evaluate the ability of ID4 to predict survival in subsets of tumours showing high or low macrophage infiltration. By culturing macrophages in conditioned media obtained from breast cancer cells in which ID4 expression was modulated by overexpression or depletion, we identified changes in the expression of ID4-dependent angiogenesis-related transcripts and microRNAs (miRNAs, miRs) in macrophages by RT-qPCR. RESULTS: We determined that ID4 and macrophage marker CD68 protein expression were significantly associated in a series of triple-negative breast tumours. Interestingly, ID4 messenger RNA (mRNA) levels robustly predicted survival, specifically in the subset of tumours showing high macrophage infiltration. In vitro and in vivo migration assays demonstrated that expression of ID4 in breast cancer cells stimulates macrophage motility. At the molecular level, ID4 protein expression in breast cancer cells controls, through paracrine signalling, the activation of an angiogenic programme in macrophages. This programme includes both the increase of angiogenesis-related mRNAs and the decrease of members of the anti-angiogenic miR-15b/107 group. Intriguingly, these miRNAs control the expression of the cytokine granulin, whose enhanced expression in macrophages confers increased angiogenic potential. CONCLUSIONS: These results uncover a key role for ID4 in dictating the behaviour of tumour-associated macrophages in breast cancer.
Assuntos
Neoplasias da Mama/genética , Proteínas Inibidoras de Diferenciação/genética , Neovascularização Patológica/genética , Neoplasias de Mama Triplo Negativas/genética , Antígenos CD/genética , Antígenos de Diferenciação Mielomonocítica/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Reprogramação Celular/genética , Citocinas/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Interleucina-8/genética , Macrófagos/patologia , MicroRNAs/genética , Neovascularização Patológica/patologia , Neoplasias de Mama Triplo Negativas/patologia , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
The abundant, nuclear-retained, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been associated with a poorly differentiated and aggressive phenotype of mammary carcinomas. This long non-coding RNA (lncRNA) localizes to nuclear speckles, where it interacts with a subset of splicing factors and modulates their activity. In this study, we demonstrate that oncogenic splicing factor SRSF1 bridges MALAT1 to mutant p53 and ID4 proteins in breast cancer cells. Mutant p53 and ID4 delocalize MALAT1 from nuclear speckles and favor its association with chromatin. This enables aberrant recruitment of MALAT1 on VEGFA pre-mRNA and modulation of VEGFA isoforms expression. Interestingly, VEGFA-dependent expression signatures associate with ID4 expression specifically in basal-like breast cancers carrying TP53 mutations. Our results highlight a key role for MALAT1 in control of VEGFA isoforms expression in breast cancer cells expressing gain-of-function mutant p53 and ID4 proteins.
Assuntos
Neoplasias da Mama/fisiopatologia , Proteínas Inibidoras de Diferenciação/metabolismo , RNA Longo não Codificante/genética , Proteína Supressora de Tumor p53/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Neoplasias da Mama/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Inibidoras de Diferenciação/genética , Mutação , Neovascularização Patológica , Isoformas de Proteínas/metabolismo , Splicing de RNA , Fatores de Processamento de Serina-Arginina/genética , Proteína Supressora de Tumor p53/genética , Fator A de Crescimento do Endotélio Vascular/biossínteseRESUMO
Telaprevir is a direct acting antiviral agent, used with pegylated interferon and ribavirin for the management of chronic hepatitis C virus (HCV) genotype 1 infection, in patients not responding to therapy with pegylated interferon and ribavirin only. Although 75% of patients achieve a sustained virological response after treatment with telaprevir, adverse drug-drug interactions and undesirable events often occur. Therefore, telaprevir monitoring is pivotal to improve the management of HCV infection. Here, the first High-Performance Liquid Chromatography-Ultraviolet (HPLC-UV) method to quantify telaprevir in human plasma of HCV-genotype 1-infected patients is reported. The volume of the plasma sample was 700 µL. This method involved automated solid-phase extraction with Oasis HLB Cartridge 1 cc (divinylbenzene and N-vinylpyrrolidone). The extracted samples were reconstituted with 150 µL of 60/40 water/acetonitrile. Thirty microliters of these samples was injected into a HPLC-UV system, and the analytes were eluted on a X Terra(®) RP18 column (250 mm × 4.6 mm i.d.) with a particle size of 5 µm. The mobile phase (ammonium acetate buffer, 150 mM, pH 8.0, and methanol:acetonitrile 50:50) was delivered at 1.0 mL/min with linear gradient elution. The total run time for a single analysis was 16 min; telaprevir was detected by UV at 276 and 286 nm. The calibration curve was linear from 312.5 to 20,000 ng/mL (r(2) > 0.996). The absolute recovery of telaprevir ranged between 89 and 93% at concentrations of quality control samples of 800, 4,000, 8,000, and 16,000 ng/mL. Both precision and accuracy were always <15%. The HPLC-UV method reported here: (i) has been validated, (ii) is currently applied to monitor telaprevir in plasma of HCV-infected patients, and (iii) appears useful in a routine laboratory. ,
