MUC1 is a highly glycosylated glycoprotein that is often overexpressed in adenocarcinomas. MUC1 has molecular diversity because of a variable number of tandem repeats (from 25-125 repeats) in the extracellular domain of its core protein. MUC1 plays an important role in facilitating invasion and metastasis of malignant cells, and it also inhibits anti-cancer immune activity against malignant cells. We hypothesize that MUC1 allele length polymorphism (variable number of tandem repeats) is associated with development of lung adenocarcinoma. We evaluated MUC1 gene polymorphism using Southern blot analysis of peripheral blood from patients with non-small cell lung cancer (n=56), patients with benign respiratory disease (n=52), and healthy volunteers (n=52). We found that large MUC1 allele length was significantly associated with lung adenocarcinoma but not with squamous cell carcinoma of the lung. Adenocarcinoma patients with a homozygous large MUC1 genotype had a worse prognosis than patients with a heterozygous (large + small) MUC1 genotype or a homozygous small MUC1 genotype. These results suggest that the large MUC1 allele is associated with susceptibility to lung adenocarcinoma and poor prognosis.
To investigate the association between glutathione-related enzymes and carboplatin (CBDCA) dose, we examined gene expression levels for both subunits of gamma-glutamylcysteine synthetase (heavy; gamma-GCSh, light; gamma-GCS1) in peripheral mononuclear cells (PMN) of lung cancer patients before and after CBDCA administration.PMN and plasma samples were obtained from 10 advanced non-small lung cancer patients before and after CBDCA administration. We analyzed the gene expression levels by reverse transcription-polymerase chain reaction.Gamma-GCSh expression levels in PMN increased within 24 hours after CBDCA administration, whereas gamma-GCS1 expression levels did not. However, the actual area under the concentration curve (AUC) of CBDCA did not correlate with gamma-GCSh expression at 24 hours or the increased ratio of gamma-GCSh expression in PMN.Expression of gamma-GCSh is induced by CBDCA, however, CBDCA AUC is not a determinant for the increased expression levels of gamma-GCSh in PMN.