Ursolic acid (UA), a naturally occurring pentacyclic triterpene, is a potent in-vitro anticancer agent, acting through control of growth, apoptosis and differentiation. As the mechanism of its proapoptotic effects on human hepatocellular carcinoma cells has not been extensively studied, we performed an in depth evaluation of the effects of UA on apoptosis in human HepG2 cells. UA was found to inhibit the proliferation of HepG2 cells in a concentration and time-dependent manner. After treatment, cells showed evidence of activation of apoptosis, including the presence of apoptotic bodies and DNA fragmentation. UA-induced apoptosis was accompanied by a significant decrease in bcl-2 and survivin expression, with the corresponding ratio of bax/bcl-2 increased. The treatment with UA also increased the protein level and enzymatic activity of caspase-3. Z-DEVD-fmk, a specific caspase-3 inhibitor, significantly inhibited both the cytotoxic effect and the DNA fragmentation induced by UA, demonstrating the requirement for caspase-3 activity in UA-induced apoptosis. Inactivation of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway was also involved, as inhibition of PI3K by LY294002 significantly increased UA-induced apoptosis. Kinetic experiments indicated that UA downregulated PI3K/p85 subunit (PI3K/p85) and phospho-Akt, before downregulating survivin. The further results also confirmed that LY294002 not only downregulated survivin alone, but considerably enhanced the repression of survivin combined with UA. UA therefore seemed to downregulate the expression of survivin by blocking PI3K/Akt. Taken together, the data suggest that the proapoptotic effect of UA on HepG2 cells is mediated by activation of caspase-3, and is highly correlated with inactivation of PI3K/Akt/survivin pathway.

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Background Germline mutations in PTEN are associated with the PTEN hamartoma tumor syndrome (PHTS), an umbrella term used to describe a spectrum of autosomal‐dominant disorders characterized by variable phenotypic manifestations associated with cell or tissue overgrowth. We report a boy who developed severe progressive abdominal distention due to a dramatic adipose mass from the age of 7 months and developed recurrent hypoinsulinemic hypoglycemia that led to seizures at the age of 4 years. Methods Trio‐based whole‐genome sequencing was performed by using blood DNA from the child and his parents. The possible pathogenic variants were verified by Sanger sequencing. Functional characterization of the identified variant was completed by western blot. Results The child inherited a single‐nucleotide deletion NM_000314.6:c.849delA (p.Glu284Argfs) in the tumor suppressor gene PTEN from his father. The paternal family members have a history of cancer. It is conceivable that PTEN loss‐of‐function induced the adipose tumor growth and hypoglycemia, although the proband did not meet the usual diagnosis criteria of Cowden syndrome or Bannayan–Riley–Ruvalcaba syndrome that are characterized by germline mutations of PTEN. Conclusion This case underlines the variability of phenotypes associated with PTEN germline mutations and provides useful information for diagnosis and genetic counseling of PTEN‐related diseases for pediatric patients.