Search

Opisthorchis felineus (Trematoda) is widespread in the Russian Federation, especially in Siberia, and other countries of Europe. Infestation of endemic area population with O. felineus reaches 80%. On animal models of the infection of closely related Opisthorchis viverrini combined with the nitrosamines' intake it has been shown that the parasite induces cholangiocarcinoma. However carcinogenic potential of O. felineus is still poorly studied. The present study is aimed to investigate the role of O. felineus in cholangiocarcinoma carcinogenesis in hamster treated additionally by dimethylnitrosamine (DMN). Golden hamsters were divided into 4 groups (15 specimens in the control group and 20 for other groups): (I) untreated control, (II) 12.5 ppm DMN solution intake, (III) infected with 50 metacercariae of O. felineus and (IV) infected with 50 metacercariae of O. felineus and 12.5 ppm DMN solution intake. According to the histological data, in the. O. felineus-infested group significant hyperplastic and dysplastic biliary changes were found considered as a precancerogenic state. Such pathological changes of bile ducts were more severe in group treated with both factors, with cholangiocarcinoma being found out at 18th week in all the animals of this group. These results demonstrate that O. felineus could play promoting role in two-step model in cholangiocarcinoma carcinogenesis and may be used to define the O.felineus group in the International Agency for Research on Cancer classification of agents, mixtures and exposures (IARC categories).

Light, electron microscopy, polymerase chain reaction (PCR), and immunohistochemistry were used to reveal the proliferative, alterative processes of hepatic parenchymal cells, P 53, K-ras, B-raf, c-Kit, p 16, APC, immunoreactive proteins Ki-67, cytokeratins 9, 14, 20, EMA, c-erb B-2, CD-117, mutated p 53 and bcl-2 genes. P53, K-ras, B-raf, c-Kit, and p 16 gene mutations were detected in the liver of animals with experimental superinvasive opisthorchiasis (SO) and cholangiocellular carcinoma (CCC). Mutations of these genes were found in the plasma samples taken from SO patients. The CCC tissue from SO patients displayed expression of the following genes: p 53 (100.0%), p 53+B-raf (50.0%), K-ras+c-Kit (33.3%), K-ras+B-rafat more than 5 cm from the tumor in 2 cases. Following 2 years, target therapy (canglait, megamin, immunomodulators) leveled mutations in 91.25% of the patients with SO.

A case of hepatobiliary liver cystadenoma in a 45-year-old female is reported. The tumour looked like a multifocal cyst 18x12x8 cm in size with yellowish content. Inner surface was represented by a column epithelium with nuclei located in the basal part of the cells. Immunohistochemically expression of cytokeratin 19 (similar to the epithelium of bile ducts) was revealed.

Histochemical examinations of 28 cancers of Vater's papilla detected argirophilic cells in 7 (25%) and argentaffinic cells in 3 (10.8%) tumors. Neoplastic endocrine cells occurred most frequently in structures of the highly differentiated papillary and tubular adenocarcinoma. The analysis of the qualitative composition of mucus produced by these tumors showed the likelihood of detection of endocrine cells in cancer of Vater's papilla to increase with higher secretion of acid mucopolysaccharides and to decrease with a higher portion of sulphomucines in them. The occurrence of impregnated endocrine cells and non-sulphated acid mucopolysaccharides in cancers of Vater's papilla appears to indicate the differentiation of the tumor tissue in the direction of the intestinal epithelium. The regular participation of argentaffinic and argirophilic cells in the development of intestinal tumors, in particular, cancer of Vater's papilla is in favour of the entodermal origin of endocrine cells of the gastrointestinal tract.