A comparison of stage of presentation for pancreatic and colorectal cancer in Pennsylvania 2000-2005.

BACKGROUND: The goal of this study was to examine how rurality, socioeconomic status (SES) and access to medical care are related to the stage at presentation of patients with colorectal (CRC) and pancreatic cancer (PC) in Pennsylvania. MATERIALS AND METHODS: Incident CRC and PC cases were identified from the Pennsylvania Department of Health. Demographic, SES, and access variables were collected at the county level. RESULTS: Increased urbanization, younger age, and male gender were shown to be significantly related to later stage at diagnosis for PC. Age and education level were significant predictors of the rate of PC, while age, education level, insurance status, rurality, and the ratio of oncologists to primary care physicians were significant predictors of the rate of CRC. CONCLUSION: Based on county-level data, urban residence, younger age, and male gender were shown to be predictors of later stage at diagnosis for PC. These findings should help guide further research into factors that may be important predictors of later stage of diagnosis.

Functional significance of the GAG trinucleotide-repeat polymorphism in the gene for the catalytic subunit of gamma-glutamylcysteine ligase.

Gamma-glutamylcysteine ligase (GCL) is the rate-limiting enzyme in glutathione (GSH) synthesis. A GAG-repeat polymorphism in the 5' UTR of the gene coding for the catalytic subunit of GCL (GCLC) has been associated with altered GSH levels in vitro. Thus, we hypothesized that this polymorphism is associated with altered GCL activity and blood GSH levels in vivo. A total of 256 healthy United States black and white adults were genotyped for the GAG polymorphism and blood GSH levels were measured. In a subset of 107 individuals, blood GCL activity was determined. Five alleles with 4, 7, 8, 9, and 10 GAG repeats were observed. The most prevalent genotype was 7/9 (40%) followed by 7/7 (32%) and 9/9 (11%). GSH levels were 15% lower in 9/9 individuals than 7/9 individuals (P=0.05). GCL activity was 21% lower in 9/9 individuals than 7/7 individuals (P=0.04). A decreasing trend of GCL activity was observed in the order of 7/7>7/9>9/9 (P=0.04). These findings show that 9/9 individuals have lower blood GSH levels, which is likely due to a decrease in GCL activity. Such individuals might be more susceptible to oxidative stress-related diseases than individuals with other genotypes.