Pyrz M.,University of Aarhus |
Wang B.,Picobella LLC |
Wabl M.,University of California at San Francisco |
Pedersen F.S.,University of Aarhus
Molecular Cancer | Year: 2010
Background: Insertional mutagenesis screens in the mouse are an acknowledged approach to identify genes involved in the pathogenesis of cancer. The potential of these screens to identify genes causally involved in tumorigenesis is not only limited to the murine host, but many of these genes have also been proven to be involved in the oncogenic process in man.Results: Through an insertional mutagenesis screen applying murine leukemia viruses in mouse, we found that Cd74 was targeted by proviral insertion in tumors of B-cell origin. This locus encodes a protein playing crucial roles in antigen presentation and B-cell homeostasis, and its deregulation is often associated with cancer in man. The distribution of insertions within the Cd74 locus prompted the identification of an alternative transcript initiated in intron 1 of Cd74 encoding an N-terminally truncated Cd74 isoform in tissues from un-infected mice, and transcriptional activation assays revealed a positive effect on the novel intronic promoter by a formerly described intronic enhancer in the Cd74 locus. Furthermore, we show that the new Cd74 isoform is IFNγ inducible and that its expression is differentially regulated from the canonical Cd74 isoform at the transcriptional level.Conclusions: We here identify Cd74 as a common insertion site in murine B-lymphomas and describe a novel IFNγ-inducible murine Cd74 isoform differentially regulated from the canonical isoform and expressed under the control of an intronic promoter. The distribution and orientation of proviral insertion sites within the Cd74 locus underscores the causal involvement of the isoforms in the murine B-lymphomagenic process. © 2010 Pyrz et al; licensee BioMed Central Ltd.
Lum A.M.,Picobella LLC |
Wang B.B.,Picobella LLC |
Beck-Engeser G.B.,University of California at San Francisco |
Li L.,Picobella LLC |
And 2 more authors.
BMC Cancer | Year: 2010
Background: GPR110 is an orphan G protein-coupled receptor--a receptor without a known ligand, a known signaling pathway, or a known function. Despite the lack of information, one can assume that orphan receptors have important biological roles. In a retroviral insertion mutagenesis screen in the mouse, we identified GPR110 as an oncogene. This prompted us to study the potential isoforms that can be gleaned from known GPR110 transcripts, and the expression of these isoforms in normal and transformed human tissues.Methods: Various epitope-tagged isoforms of GPR110 were expressed in cell lines and assayed by western blotting to determine cleavage, surface localization, and secretion patterns. GPR110 transcript and protein levels were measured in lung and prostate cancer cell lines and clinical samples, respectively, by quantitative PCR and immunohistochemistry.Results: We found four potential splice variants of GPR110. Of these variants, we confirmed three as being expressed as proteins on the cell surface. Isoform 1 is the canonical form, with a molecular mass of about 100 kD. Isoforms 2 and 3 are truncated products of isoform 1, and are 25 and 23 kD, respectively. These truncated isoforms lack the seven-span transmembrane domain characteristic of GPR proteins and thus are not likely to be membrane anchored; indeed, isoform 2 can be secreted. Compared with the median gene expression of ~200 selected genes, GPR110 expression was low in most tissues. However, it had higher than average gene expression in normal kidney tissue and in prostate tissues originating from older donors. Although identified as an oncogene in murine T lymphomas, GPR110 is greatly overexpressed in human lung and prostate cancers. As detected by immunohistochemistry, GPR110 was overexpressed in 20 of 27 (74%) lung adenocarcinoma tissue cores and in 17 of 29 (59%) prostate adenocarcinoma tissue cores. Additionally, staining with a GPR110 antibody enabled us to differentiate between benign prostate hyperplasia and potential incipient malignancy.Conclusion: Our work suggests a role for GPR110 in tumor physiology and supports it as a potential therapeutic candidate and disease marker for both lung and prostate cancer. © 2010 Lum et al; licensee BioMed Central Ltd.
Picobella Llc | Date: 2013-01-21
Methods for detecting and treating prostate and lung cancer are disclosed In practicing the method, a subject sample is assayed for GPR110 protein or its RNA transcript, and the GPR110 or transcript level observed is used in determining whether the subject has an elevated GPR110 level associated with prostate or lung cancer. Patients with such elevated levels may be treated, in accordance with the invention, with a variety of GPR110 related immunotherapy agents.