[A study on primary liver cancer in tree shrews induced by human hepatitis B virus and aflatoxin B1]

Among 41 tree shrews exposed to aflatoxin B1(AFB1), 17 were experimental infected by human hepatitis B virus (HHBV) and 24 were uninfected. After 158 weeks, 9 cases (52.94%) of primary liver cancer (PLC) were found out of the 17 tree shrews infected by HHBV and only 3 cases (12.5%) developed PLC in the 24 uninfected animals. Significant difference of PLC incidence was seen between the HHBV-infected and uninfected groups (P less than 0.05). Moreover, 1/9 of the tree shrews that had been infected by HHBV but without exposure to AFB1 developed PLC at the 83rd week. No PLC was found in 6 tree shrews that had neither been infected with HHBV nor been exposed to AFB1. These results demonstrate the possible etiologic relationship between HHBV infection and PLC, and the synergistic effects of HHBV and AFB1 during PLC development.