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Sippy Kaur

Publications and source records attributed to Sippy Kaur.

4 recordsLinked to original sources
PubMed2006

Molecular karyotyping in sarcoma diagnostics and research.

Conventional cytogenetic and molecular genetic studies have both clinical and biological significance in sarcomas. However, the resolution of these methods does not always suffice to screening of novel, specific genetic changes, such as small deletions, amplifications, and fusion genes. Tumor-specific chromosomal translocations revealed by cytogenetic and molecular methods play a decisive role in the differential diagnosis of sarcomas. The novel molecular karyotyping techniques have proven to be powerful in the screening of clinically and biologically relevant molecular changes in human neoplasias. A variety of platforms for molecular karyotyping is available, e.g., arrayed cDNA clones or oligonucleotides that can be used in microarray-based comparative genomic hybridization (CGH) and gene expression analysis. We review here the clinically most relevant cytogenetic and molecular changes in sarcomas and describe latest microarray techniques for screening of clinically relevant gene copy number and expression changes.

Genetic Testing↗
PubMed2006

Gene copy number profiling of soft-tissue leiomyosarcomas by array-comparative genomic hybridization.

Leiomyosarcoma (LMS) is a rare malignant mesenchymal tumor of smooth muscle cells. Chromosomal aberrations in LMS have been studied, but the cytogenetic data that have been published so far are complex, limited, and incomplete. Here, we performed for the first time a high-resolution genome-wide array comparative genomic hybridization (CGH) analysis (aCGH) on a pool of 14 low- and high-grade LMS cases to obtain gene-level information about the amplified and deleted regions that may play a role in the development and progression of LMS. Our aCGH results indicated that 2,218 genes were involved in 25 altered chromosomal regions; 9 regions in low-grade LMS, 12 regions in high-grade LMS, and 4 minimal common regions shared by low- and high-grade LMS. The frequency of DNA copy number gains in high-grade LMS was threefold compared to low-grade LMS, whereas losses in low-grade LMS were almost twice as frequent as in high-grade LMS. Both low- and high-grade tumors shared two minimal common regions of gain (15q26 approximately qter and 17p13.1 approximately q11) and loss (6p12 approximately p21.3 and 13q14.3 approximately qter). Moreover, our findings indicated that low- and high-grade LMS and osteosarcoma share 12 genes located in the 17p amplicon. In conclusion, by using aCGH, we were able to define the precise location of the altered chromosomal areas and to identify putative tumor suppressor genes and oncogenes therein. The list of altered genes in the minimal common regions is available as at our web site (http://www.helsinki.fi/cmg/microarray_data).

Adult↗
PubMed2005

Gene amplifications in osteosarcoma-CGH microarray analysis.

Little is known about the genomic alterations underlying osteosarcoma. We performed a genomewide high-resolution gene copy number analysis of 22 osteosarcoma samples using comparative genomic hybridization on a cDNA microarray that contained cDNA clones of about 13,000 genes. Nineteen of the 22 cases had amplifications that on average spanned more than 1 Mb and contained more than 10 genes. Numerous regions of gain and loss were identified, and their boundaries were defined at high resolution. Novel amplicons were found at 14q11, 17q25, and 22q11-q13. Earlier-known large amplified regions were detected at 12q11-q15, 8q24, 6p12-p13, and 17p11-p13 in 8, 6, 5, and 4 of the 22 samples, respectively. Amplification of 12q was observed more frequently (36% of the cases) than previously reported. Previously known small amplicons at 1p34-p36, 1q21, 19q13, and 21q22 were seen in at least three cases. Our results implicate TOM1L2 and CYP27B1 as having roles as novel targets for the 17p and 12q amplicons, respectively. Details (www.helsinki.fi/cmg) of the amplified genes in each amplicon provide valuable raw data for further in silico studies.

Adolescent↗