engleski

Loss of imprinting of IGF2 and H19, loss of heterozygosity of IGF2R and CTCF, and Helicobacter pylori infection in laryngeal squamous cell carcinoma

Imprinting analyses of IGF2 and H19, loss of heterozygosity (LOH) analyses of IGF2R and CTCF and Helicobacter pylori detection were performed on 35 human laryngeal squamous cell carcinomas (LSCC). Forty-six percent of the tumors were heterozygous for IGF2 and 54% were informative for the H19 gene. Biallelic expression of IGF2 was observed in 33% (5/15) of the tumors and in 27% (4/15) of adjacent non-tumorous laryngeal tissues. H19 loss of imprinting (LOI) was observed in 24% (4/17) of the tumors. For IGF2R and CTCF, 71% (25/35) and 50% (17/34) of samples were heterozygous and LOH was detected in 12% (3/25) and 6% (1/17) of the tumors, respectively. H. pylori was found in 26% (9/35) of these tumors. Among these, four were informative for the imprinting analysis. The presence of H. pylori had no effect on IGF2/H19 imprinting. Only the H. pylori detection was further broadened with an additional 47 laryngeal tumors, resulting in a total final positivity close to 16% (13/82). This study represents the largest comprenhensive IGF2/H19 imprinting study done so far on well-defined samples of human laryngeal carcinomas and corresponding non-tumorous tissues. For the first time, the analyses of IGF2/H19 imprinting have been broadened with LOH analyses of IGF2R and CTCF as both these genes act as modulators of IGF2 and H19 activity. Although there were indications that H. pylori may be present in LSCS, we are the first to show its presence in LSCS by two direct techniques: Giemsa staining and nested-PCR.

Laryngeal squamous cell carcinoma ; IGF2 LOI ; H19 LOI ; IGF2R LOH ; CTCF LOH ; Helicobacter pylori

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