ABSTRACT
ObjectiveTo explore the inhibitory effect of water extract of Broussonetiae Fructus on hepatocellular carcinoma （HCC） induced by diethyl nitrosamine （DEN） in mice based on homologous phosphatase and tensin homolog/phosphatidylinositol 3-kinase/protein kinase B （PTEN/PI3K/Akt） signaling pathway. MethodThe primary HCC mouse model was constructed by intraperitoneal injection of DEN solution， and the HCC mice were randomly divided into model group， sorafenib group （0.01 g·kg-1·d-1）， low-dose Broussonetiae Fructus water extract group （0.9 g·kg-1·d-1）， medium-dose Broussonetiae Fructus water extract group （1.8 g·kg-1·d-1）， and high-dose Broussonetiae Fructus water extract group （3.6 g·kg-1·d-1）， with 10 mice in each group. Another 10 C57BL/6 mice were selected as a control group and intraperitoneally injected with an equal volume of normal saline. Mice were treated with different concentrations of Broussonetiae Fructus water extract when liver cancer-like white nodules appeared. sorafenib group was treated with sorafenib. The control group and model group were intraperitoneally injected with normal saline. The activities of alkaline phosphatase （ALP）， aspartate aminotransferase （AST）， alanine aminotransferase （ALT）， and γ-glutamyl transferase （γ-GT） in the serum of mice were detected by the biochemical analyzer. The expression levels of alpha-fetoprotein （AFP） and carcinoembryonic antigen （CEA） were detected by enzyme-linked immunosorbent assay （ELISA）. The degree of hepatocyte canceration and hepatocyte injury were observed by Hematoxylin-eosin （HE） and Masson staining. The proliferation of HCC cells was observed by immunohistochemical staining. The apoptosis of HCC cells in mice was observed by erminal-deoxynucleotidyl transferase mediated nick end labelling （TUNEL） staining. The expression levels of PTEN， PI3K， Akt， and p-Akt proteins related to the PTEN/PI3K/Akt signaling pathway were detected by Western blot. ResultCompared with the control group， the activities of ALP， AST， ALT， and γ-GT， as well as the expression levels of AFP and CEA in the model group were significantly increased （P<0.01）. Carcinogenesis and inflammatory cell infiltration were obvious in liver tissue of mice， and a large number of blue collagen fiber hyperplasia was found. The number of Ki67 positive cells was significantly increased （P<0.01）， and the expression level of PTEN protein was significantly decreased， while PI3K and p-Akt protein expression was increased （P<0.01）. Compared with the model group， the activities of ALP， AST， ALT， and γ-GT， as well as the expression levels of AFP and CEA in the medium-dose and high-dose Broussonetiae Fructus water extract groups were significantly decreased （P<0.05， P<0.01）. The degree of carcinogenesis and inflammatory cell infiltration in liver tissue were reduced， and the collagen fiber hyperplasia was significantly reduced. The number of Ki67 positive cells was significantly decreased， and the number of TUNEL positive apoptotic cells was significantly increased （P<0.05， P<0.01）. PTEN protein expression was increased， while p-Akt protein expression was significantly decreased （P<0.05， P<0.01）. ConclusionThe water extract of Broussonetiae Fructus has a significant inhibitory effect on DEN-induced primary HCC in mice， and its mechanism may be related to the regulation of key protein expressions in the PTEN/PI3K/Akt signaling pathway.