Clinicopathological significance of core 2 beta 1,6-N-acetylglucosaminyltransferase messenger RNA expressed in the pulmonary adenocarcinoma determined by in situ hybridization

Cell surface carbohydrates of epithelial cells play important roles in tumo r progression, Previously, we have shown that expression of core 2 branched O-glycans in colorectal cancer is closely correlated with the vessel invas ion and depth of invasion (K. Shimodaira ef al., Cancer Res., 57: 5201-5206 , 1997), To test whether this is also the case in human lung cancer, we hav e examined the expression pattern of core 2 beta1,6-N-acetylglucosaminyltra nsferase (C2GnT) mRNA responsible for the biosynthesis of core 2 branched O -glycans in 41 cases of lung canter. Using in situ hybridization, C2GnT mRN A was detected in 73.2% of the lung cancer cells, irrespective of the histo pathological type; whereas in normal lung tissues, its expression was restr icted to the basal cells of bronchial mucosa, These results indicate that t he expression level of C2GnT mRNA was significantly enhanced in association with malignant transformation. Statistical analysis between the C2GnT mRNA expressed in pulmonary adenocarcinoma and clinicopathologic al variables r evealed that the expression of C2GnT was correlated with vessel invasion an d lymph node metastasis with significant difference (P < 0.05), but express ion of sialyl Le(X), which is frequently expressed in the adenocarcinoma. w as not significantly correlated with lymph node metastasis. These results i ndicate that C2GnT mRNA detected by in situ hybridization reflects the mali gnant potentials of pulmonary adenocarcinoma, because lymph node metastasis is the must affecting factor to the patients' prognosis.