HGNC Approved Gene Symbol: GPC5
Cytogenetic location: 13q31.3 Genomic coordinates (GRCh38): 13:91,398,621-92,867,237 (from NCBI)
Veugelers et al. (1997) identified a novel EST database sequence with homology to members of the glypican family (see GPC1, 600395). They sequenced the clone and completed the 5-prime end of the cDNA using RACE PCR. The cDNA sequence of GPC5 predicts a 572-amino acid polypeptide with 21% identity to GPC1 and 40% identity to GPC3 (300037). Northern blot analysis revealed that the gene is expressed as a 3-kb message in brain and several other human tissues. Veugelers et al. (1997) found that GPC-transfectant cells expressed heparin sulfate proteoglycan core proteins that were not present in control cells.
Among the chromosomal regions showing recurrent amplification in comparative genomic hybridization (CGH) analyses of various types of lymphoma, 13q31-q32 is of particular interest because (1) gains of copy number are frequent in that region, e.g., in 8 (18%) of 45 cases of follicular lymphoma (Neat et al., 2001) and 4 (29%) of 14 cases of primary cutaneous B-cell lymphoma (Mao et al., 2002) and (2) genomic alterations within or around this region have also been implicated in other malignancies such as small and non-small cell lung cancers and squamous cell carcinoma of the head and neck (Knuutila et al., 1998). Yu et al. (2003) attempted to define by fluorescence in situ hybridization a common region at 13q31-q32 in which to explore genes that might be targets for the amplification events. Although the commonly amplified region they defined was relatively large (approximately 4 Mb), only 1 true gene, GPC5, was found there. GPC5 was overexpressed in lymphoma cell lines that had shown amplification, in comparison with those that had not. These findings suggested that GPC5 is a likely target for amplification, and that overexpression of this gene may contribute to development and/or progression of lymphomas and other tumors. That only 1 'true gene' was found in the region of amplification may reflect the well-known relative sparsity of genes on chromosome 13, as indicated by gene mapping studies in the 1980s, by EST and other transcript studies in the 1990s, and analyses of the 'complete' genome sequence in the early years of this century.
Veugelers et al. (1997) used fluorescence in situ hybridization to map the GPC5 gene to chromosome 13q32.
Knuutila, S., Bjorkqvist, A. M., Autio, K., Tarkkanen, M., Wolf, M., Monni, O., Szymanska, J., Larramendy, M. L., Tapper, J., Pere, H., El-Rifai, W., Hemmer, S., Wasenius, V. M., Vidgren, V., Zhu, Y. DNA copy number amplifications in human neoplasms: review of comparative genomic hybridization studies. Am. J. Path. 152: 1107-1123, 1998. [PubMed: 9588877]
Mao, X., Lillington, D., Child, F., Russell-Jones, R., Whittaker, S. Comparative genomic hybridization analysis of primary cutaneous B-cell lymphomas: identification of common genomic alteration in disease pathogenesis. Genes Chromosomes Cancer 35: 144-155, 2002. [PubMed: 12203778] [Full Text: https://doi.org/10.1002/gcc.10104]
Neat, M. J., Foot, N., Jenner, M., Goff, L., Ashcroft, K., Burford, D., Dunham, A., Norton, A., Lister, T. A., Fitzgibbon, J. Localisation of a novel region of recurrent amplification in follicular lymphoma to an ~6.8 Mb region of 13q32-33. Genes Chromosomes Cancer 32: 236-243, 2001. [PubMed: 11579463] [Full Text: https://doi.org/10.1002/gcc.1187]
Veugelers, M., Vermeesch, J., Reekmans, G., Steinfeld, R., Marynen, P., David, G. Characterization of glypican-5 and chromosomal localization of human GPC5, a new member of the glypican gene family. Genomics 40: 24-30, 1997. [PubMed: 9070915] [Full Text: https://doi.org/10.1006/geno.1996.4518]
Yu, W., Inoue, J., Imoto, I., Matsuo, Y., Karpas, A., Inazawa, J. GPC5 is a possible target for the 13q31-q32 amplification detected in lymphoma cell lines. J. Hum. Genet. 48: 331-335, 2003. [PubMed: 12721791] [Full Text: https://doi.org/10.1007/s10038-003-0026-2]