Role of Cyanobacteria and cyanotoxins in liver cancer development
Oral Cyanobacteria and other bacterial taxa will be evaluated in oral DNA samples of HCC cases, CLD cases, and matched controls by Illumina MiSeq 16S rRNA. Serum cyanotoxins (microcystin/nodularin, cylindrospermopsin, and anabaenopeptin) will be measured by validated ELISA assays in HCC cases, CLD cases, and matched controls. Cyanotoxins will also be measured in urine and oral samples in subsets of cases and controls. Tumor gene expression will be evaluated by Nanostring and compared by serum cyanotoxin levels in a subset of HCC cases with paired tumor tissue and blood.
The statistical analysis will focus on the association of oral Cyanobacteria and cyanotoxins (microcystin/nodularin, cylindrospermopsin, and anabaenopeptin) with risk of HCC and CLD.
Comparisons will be made by HCC risk factors (hepatitis B and C, excess alcohol, smoking, obesity, type 2 diabetes, hyperlipidemia) as well as dietary, occupational, recreational, and residential history.
Comparisons will also be made by race/ethnicity including Asians, Pacific Islanders, Hispanics, Blacks, and Whites.
Specific Aim 1. To evaluate the association of oral Cyanobacteria with risk of chronic liver disease and hepatocellular carcinoma
Specific Aim 2. To evaluate the association of liver cyanotoxins with risk of chronic liver disease and hepatocellular carcinoma.
Specific Aim 2. To identify tumor gene expression signatures specific to Cyanobacteria and cyanotoxin exposure.
Brenda Hernandez (University of Hawaii)
Linda Wong (University of Hawaii)
Lynne Wilkens (University of Hawaii)
Katherine McGlynn (National Cancer Institute)