Project description:The MYB-NFIB gene is a driver-mutation in the majority of adenoid cystic carcinomas (ACCs) and believed to control a large number of genes involved in tumorigenesis. This experiment investigates the effects on gene expression after siRNA knock-down of MYB-NFIB and/or inhibition of IGF1R/INSR signaling in ACC cells.
Project description:MYB activation is proposed to underlie development of adenoid cystic cancer (ACC), an aggressive salivary gland tumor with no effective systemic treatments. To discover druggable targets for ACC, we performed global mRNA/miRNA analyses of 12 ACC with matched normal tissues, and compared these data with 14 mucoepidermoid carcinomas (MEC) and 11 salivary adenocarcinomas (ADC). We detected a unique ACC gene signature of 1160 mRNAs and 22 miRNAs. MYB was the top-scoring gene (18-fold induction), however we observed the same signature in ACC without detectable MYB gene rearrangements. We also found 4 ACC tumors (1 among our 12 cases and 3 from public databases) with negligible MYB expression that retained the same ACC mRNA signature including over-expression of extracellular matrix (ECM) genes. Integration of this signature with somatic mutational analyses suggests that NOTCH1 and RUNX1 participate with MYB to activate ECM elements including the VCAN/HAPLN1 complex. We observed that forced MYB-NFIB expression in human salivary gland cells alters cell morphology and cell adhesion in vitro and depletion of VCAN blocked tumor cell growth of a short-term ACC tumor culture. In summary, we identified a unique ACC signature with parallel MYB-dependent and independent biomarkers and identified VCAN/HAPLN1 complexes as a potential target.
Project description:MYB activation is proposed to underlie development of adenoid cystic cancer (ACC), an aggressive salivary gland tumor with no effective systemic treatments. To discover druggable targets for ACC, we performed global mRNA/miRNA analyses of 12 ACC with matched normal tissues, and compared these data with 14 mucoepidermoid carcinomas (MEC) and 11 salivary adenocarcinomas (ADC). We detected a unique ACC gene signature of 1160 mRNAs and 22 miRNAs. MYB was the top-scoring gene (18-fold induction), however we observed the same signature in ACC without detectable MYB gene rearrangements. We also found 4 ACC tumors (1 among our 12 cases and 3 from public databases) with negligible MYB expression that retained the same ACC mRNA signature including over-expression of extracellular matrix (ECM) genes. Integration of this signature with somatic mutational analyses suggests that NOTCH1 and RUNX1 participate with MYB to activate ECM elements including the VCAN/HAPLN1 complex. We observed that forced MYB-NFIB expression in human salivary gland cells alters cell morphology and cell adhesion in vitro and depletion of VCAN blocked tumor cell growth of a short-term ACC tumor culture. In summary, we identified a unique ACC signature with parallel MYB-dependent and independent biomarkers and identified VCAN/HAPLN1 complexes as a potential target.
Project description:MYB activation is proposed to underlie development of adenoid cystic cancer (ACC), an aggressive salivary gland tumor with no effective systemic treatments. To discover druggable targets for ACC, we performed global mRNA/miRNA analyses of 12 ACC with matched normal tissues, and compared these data with 14 mucoepidermoid carcinomas (MEC) and 11 salivary adenocarcinomas (ADC). We detected a unique ACC gene signature of 1160 mRNAs and 22 miRNAs. MYB was the top-scoring gene (18-fold induction), however we observed the same signature in ACC without detectable MYB gene rearrangements. We also found 4 ACC tumors (1 among our 12 cases and 3 from public databases) with negligible MYB expression that retained the same ACC mRNA signature including over-expression of extracellular matrix (ECM) genes. Integration of this signature with somatic mutational analyses suggests that NOTCH1 and RUNX1 participate with MYB to activate ECM elements including the VCAN/HAPLN1 complex. We observed that forced MYB-NFIB expression in human salivary gland cells alters cell morphology and cell adhesion in vitro and depletion of VCAN blocked tumor cell growth of a short-term ACC tumor culture. In summary, we identified a unique ACC signature with parallel MYB-dependent and independent biomarkers and identified VCAN/HAPLN1 complexes as a potential target.
Project description:Adenoid cystic carcinoma (ACC) is one of the most common malignancies that arise in the salivary glands, with an incidence of 4.5 per 1,000,000. It can also arise in glandular tissue closely related to salivary glands in the lacrimal gland, nasal passages and tracheobronchial tree, as well as in glands of the breast and vulva. At all of these sites, it is characterized by a distinctive histology of basaloid epithelial cells arranged in cribriform or tubular patterns, usually demonstrating abundant hyaline extracellular matrix secretion and some degree of myoepithelial differentiation. ACC is generally a slow-growing tumor characterized by a protracted clinical course, usually well over 5 years in duration, marked by regional recurrence, distant metastasis and/or spread along peripheral nerves. A recurrent chromosomal translocation, t(6;9)(q23;p21), has been identified in ACC, and recently it has been discovered that in a majority of ACC the MYB gene on chromosome 6 is fused to the 3’ terminus of the NFIB gene on chromosome 9, creating a fusion gene product resulting in increased MYB-related transcriptional activation. Recently it has been determined that most cell lines with attribution of ACC derivation are either contaminants of other cell lines or do not have the characteristic MYB-NFIB translocation. Also, there are no animal models of this histologically and genetically defined tumor type. To address the paucity of experimental and pre-clinical models systems of ACC, we have for several years been establishing xenograft tumor lines from clinical samples of ACC. We describe our experience with these models and their characterization here. Analysis of 12 xenografts of human adenoid cystic carcinoma (ACC) along with 10 samples of ACC directly from humans. Note, that 12 of these samples are paired primary ACC & xenograft ACC from the same individual (6 pairs in total).
Project description:Commonalities and dissimilarities between the IGF1R and INSR pathways Insulin and insulin-like growth factor-1 (IGF1), acting respectively via the insulin (INSR) and IGF1 (IGF1R) receptors, play key developmental and metabolic roles throughout life. In addition, both signaling pathways fulfill important roles in cancer initiation and progression. The inherent complexity of the INSR/IGF1R pathways, along with the well documented cross-talk between insulin-like ligands and receptors, translated into a disappointingly slow pace in the development of INSR/IGF1R-directed therapies in oncology. The present study was aimed at identifying mechanistic differences between INSR and IGF1R using a recently developed bioinformatics tool, the Biological Network Simulator (BioNSi). This application allows to import and merge multiple pathways and interaction information from the KEGG database into a single network representation. The BioNsi network simulation tool allowed us to exploit the availability of gene expression data derived from breast cancer cell lines with specific disruptions of the INSR or IGF1R genes in order to investigate potential differences in protein expression that might be linked to biological attributes of the specific receptor networks. Modeling-generated information was corroborated by experimental and biological assays. Our simulation analysis identified a number of commonalities and, most importantly, dissimilarities between the IGF1R and INSR pathways that were experimentally validated and that might help explain the basis for the biological differences between these networks.
Project description:Adenoid cystic carcinoma (ACC) is one of the most common malignancies that arise in the salivary glands, with an incidence of 4.5 per 1,000,000. It can also arise in glandular tissue closely related to salivary glands in the lacrimal gland, nasal passages and tracheobronchial tree, as well as in glands of the breast and vulva. At all of these sites, it is characterized by a distinctive histology of basaloid epithelial cells arranged in cribriform or tubular patterns, usually demonstrating abundant hyaline extracellular matrix secretion and some degree of myoepithelial differentiation. ACC is generally a slow-growing tumor characterized by a protracted clinical course, usually well over 5 years in duration, marked by regional recurrence, distant metastasis and/or spread along peripheral nerves. A recurrent chromosomal translocation, t(6;9)(q23;p21), has been identified in ACC, and recently it has been discovered that in a majority of ACC the MYB gene on chromosome 6 is fused to the 3’ terminus of the NFIB gene on chromosome 9, creating a fusion gene product resulting in increased MYB-related transcriptional activation. Recently it has been determined that most cell lines with attribution of ACC derivation are either contaminants of other cell lines or do not have the characteristic MYB-NFIB translocation. Also, there are no animal models of this histologically and genetically defined tumor type. To address the paucity of experimental and pre-clinical models systems of ACC, we have for several years been establishing xenograft tumor lines from clinical samples of ACC. We describe our experience with these models and their characterization here.
Project description:Salivary gland adenoid cystic carcinoma (ACC) is a rare malignancy with limited treatment options. The development of novel therapies is hindered by a lack of preclinical models. We have generated several ACC patient-derived xenograft (PDX) lines that retain the physical and genetic properties of the original tumours, including the presence of the common MYB/MYBL1-NFIB translocation. Using these PDXs, we have developed the conditions for the generation of 2D and 3D ACC models that retain MYB expression and can be used for drug studies. Using these models, we show in vitro and in vivo sensitivity of ACC cells to the bromodomain degrader, dBET6. Molecular studies show a decrease in BRD4 and MYB protein levels and target gene expression with treatment. The most prominent effect of dBET6 on tumours in vivo was a change in the relative composition of ACC cell types expressing either myoepithelial or ductal markers. We show that dBET6 inhibits the progenitor function of ACC cells, particularly in the myoepithelial marker-expressing population, revealing a cell-type-specific sensitivity. These studies reveal a novel mechanistic impact of bromodomain inhibitors on tumours and highlight the need to impact both cell-type populations for more effective treatments in ACC patients.
Project description:Resistance to insulin and insulin-like growth factor 1 (IGF1) in pancreatic β-cells causes overt diabetes in mice; thus, therapies that sensitize β-cells to insulin may protect patients with diabetes against β-cell failure. Here we identify an inhibitor of insulin receptor (INSR) and IGF1 receptor (IGF1R) signalling in mouse β-cells, which we name the insulin inhibitory receptor (inceptor; encoded by the gene Iir). Inceptor contains an extracellular cysteine-rich domain with similarities to INSR and IGF1R4, and a mannose 6-phosphate domain that is also found in the IGF2 receptor (IGF2R)5. Knockout mice that lack inceptor (Iir-/-) exhibit signs of hyperinsulinaemia and hypoglycaemia, and die within a few hours of birth. Molecular and cellular analyses of embryonic and postnatal pancreases from Iir-/- mice showed an increase in the activation of INSR–IGF1R in Iir-/- pancreatic tissue, resulting in an increase in the proliferation and mass of β-cells. Similarly, inducible β-cell-specific Iir-/- knockout in adult mice and in ex vivo islets led to an increase in the activation of INSR–IGF1R and increased proliferation of β-cells, resulting in improved glucose tolerance in vivo. Mechanistically, inceptor interacts with INSR–IGF1R to facilitate clathrin-mediated endocytosis for receptor desensitization. Blocking this physical interaction using monoclonal antibodies against the extracellular domain of inceptor resulted in the retention of inceptor and INSR at the plasma membrane to sustain the activation of INSR–IGF1R in β-cells. Together, our findings show that inceptor shields insulinproducing β-cells from constitutive pathway activation, and identify inceptor as a potential molecular target for INSR–IGF1R sensitization and diabetes therapy.
Project description:<p>Adenoid cystic carcinoma (ACC) typically emanate from the major and minor salivary glands of the head and neck. ACCs have high rates of perineural invasion, locoregional recurrence, and distant metastasis. Here we report sequencing of 60 tumor/normal pairs and find substantial mutational diversity. On pathway analysis, a significant percentage of mutations involved chromatin remodeling, DNA damage, protein kinase A signaling, and FGF/IGF/PI3K signaling. Whole genome sequencing and FISH confirmed the MYB-NFIB translocation as the main structural variant in ACC. Evaluation of potential driver mutations KDM6A and PIK3CA reveal that specific, observed alterations impart functional consequences. Collectively, our data delineate the ACC mutational landscape and establish a molecular foundation for investigating new therapies for this disease.</p>