[The relationship between cyanotoxin (microcystin, MC) in pond-ditch water and primary liver cancer in China].
OBJECTIVE
To explore the relationship between primary liver cancer (PLC) and MC in drinking pond-ditch water.


METHODS
Epidemiological and ecological assays, Meta-analysis and risk assessment were used in this study. Cyanotoxin (Microcystin, MC) in the water of different sources was detected by ELISA. The F344 and HBVx transgenic mice were used to confirm the promotion effect on PLC and the synthetically carcinogenic effect of HBV, aflatoxin and MC.


RESULTS
Using Meta-analysis the results of six case-control studies showed that the pooled odds ratio (OR) was 2.46 (95% CI 1.69-2.59), population attributable rick (PAR) was 30.39% (95% CI, 23.30%-37.47%), heterogeneity test P > 0.05. Eutrophication led to cyanobacterial bloom in the pond-ditch water. Cyanotoxin released from dead cyanobacteria was hepatotactic tumor promoter. In HBVx transgenic rats, hepatocellular carcinoma was induced by the joint administration of aflatoxin B1 and cyanotoxin. Epidemiological study showed that the recombined index of HBsAg, aflatoxin-albumin adducts and drinking of pond-ditch water correlated with PLC mortalities in 13 townships.


CONCLUSIONS
Microcystin in the pond-ditch water is a hepatotactic toxin which can induce hepatitis and promote development of hepatocellular carcinoma. The combined effect of microcystin, HBV and aflatoxin may be responsible for the endemicity of PLC.
Yu
S
S
Institute of Preventive Medicine, Fudan University, Shanghai 200032, China.
Zhao
N
N
Zi
X
X
D016604:Aflatoxin B1 / Q000633:toxicity; D000818:Animals; D030801:Animals, Genetically Modified; D006528:Carcinoma, Hepatocellular / Q000139:chemically induced / Q000473:pathology; D002648:Child; D002681:China; D005618:Fresh Water / Q000737:chemistry*; D005982:Glutathione Transferase / Q000187:drug effects / Q000378:metabolism; D006498:Hepatectomy; D006801:Humans; D008099:Liver / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D008113:Liver Neoplasms / Q000139:chemically induced / Q000473:pathology*; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced / Q000473:pathology; D008297:Male; D052998:Microcystins; D010456:Peptides, Cyclic / Q000009:adverse effects / Q000032:analysis*; D051381:Rats; D011916:Rats, Inbred F344; D015534:Trans-Activators / Q000235:genetics / Q000502:physiology; D054334:Viral Regulatory and Accessory Proteins
D052998:Microcystins; D010456:Peptides, Cyclic; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; C078588:microcystin; D016604:Aflatoxin B1; D005982:Glutathione Transferase