Age and seasonal variation and establishment of reference intervals for water-soluble vitamins determined by liquid chromatography tandem mass spectrometry.

OBJECTIVES: We aimed to establish reference intervals for water-soluble vitamins determined by liquid chromatography tandem mass spectrometry to improve the diagnosis of vitamin deficiency and outcomes of associated conditions. METHODS: In this retrospective analysis of 24 810 specimens, we aimed to examine sex-, age-, and season-related variations in vitamin levels in different groups, set reference-value intervals for vitamin levels, and evaluate these reference values against those recommended by manufacturers. RESULTS: Levels of vitamins B3, B5, B6, B7, and B12 were higher, and those of vitamins B2, B9, and C were lower, in men than in women. There were seasonal variations in levels of vitamins B1, B3, B5, B6, B9, B12, and C. Levels of vitamins B1, B2, B3, B5, B6, B7, B9, and C differed across age groups; vitamin B1 displayed significant differences between ages 0 to 14 years and adults compared with reference change values. The lower limits of vitamins B1 (ages 15-100 y), B2, B3, B7, and C were lower, and that of vitamin B5 was higher, than the recommended reference values. Finally, the upper limits of vitamins B1, B3, B5, B6, and B7 were lower than the recommended values. CONCLUSIONS: For values obtained using liquid chromatography tandem mass spectrometry, the lower limits of reference intervals for vitamins B1 (ages 15-100 y), B2, B3, B7, and C should be lowered, that of vitamin B5 should be raised, and the upper limits of reference intervals for vitamins B1, B3, B5, B6, and B7 should be lowered.

Cancer stem cells and hypoxia-inducible factors (Review).

Cancer stem cells (CSCs), also known as tumor-initiating cells, are a subpopulation of tumor cells that exhibit properties similar to those of normal stem cells. Oxygen is an important regulator of cellular metabolism; hypoxia-inducible factors (HIFs) mediate metabolic switches in cells in hypoxic environments. Hypoxia clearly has the potential to exert a significant effect on the maintenance and evolution of CSCs. Both HIF­1α and HIF­2α may contribute to the regulation of cellular adaptation to hypoxia and resistance to cancer therapies. This review provides an overview of the roles of HIFs in CSCs. HIF­1α and HIF­2α have significant prognostic and predictive value in the clinic and the concept of personalized medicine should be applied in designing clinical trials for HIF inhibitors.

The tumor promoting roles of HSP60 and HIF2α in gastric cancer cells.

The roles of HSP60 and HIF2α in diagnosis, prognosis, and prevention and treatment of various human cancers have been detected. However, the combined roles of HSP60 and HIF2α on the prognosis of patients with gastric cancer remain unclear. In this work, we confirmed that the levels of HSP60 and HIF2α messenger RNA (mRNA) and protein were higher in gastric cancer tissues than that in matched normal tissues by using real-time PCR and Western blot. Furthermore, we confirmed that inhibition of HSP60 or HIF2α could induce apoptosis and inhibit cell mobility. Co-immunoprecipitation (co-IP) was performed to determine the interaction between HSP60 and HIF2α. Lastly, we confirmed that knockdown of HSP60 or HIF2α induced apoptosis in gastric cancer cells is negatively related to the MEK/ERK signaling in vitro. In summary, HSP60 or HIF2α protein expression may be a predictive marker for the prognosis of the patients with gastric cancer. Targeting HSP60 and HIF2α could be a future strategy to improve survival of gastric patients with poor prognosis.

DBD-F induces apoptosis in gastric cancer-derived cells through suppressing HIF2α expression.

PURPOSE: Gastric cancer is the third leading cause of cancer-related death in China. Accumulating evidence indicates that HIF2α may affect the aggressiveness of gastric cancer. It has also been found that HIF2α C-terminal PAS domains can form complexes with inactive benzoxadiazole antagonists. Here, the anti-tumor effect of 4-(N,Ndimethylaminosulphonyl)-7-fluoro-1,2,3-benzoxadiazole (DBD-F) on human gastric cancer cells was examined using both in vitro and in vivo assays. METHODS AND RESULTS: We found that DBD-F can induce apoptosis and inhibit the mobility of MKN28 and MKN45 gastric cancer-derived cells in vitro. We also found that DBD-F can suppress tumor growth in established gastric cancer-derived xenograft models in vivo. Finally, we found that DBD-F can inhibit HIF2α expression in gastric cancer-derived cells. CONCLUSIONS: From our findings we conclude that DBD-F (i) is cytotoxic to gastric cancer-derived cells and (ii) can induce apoptosis in these cells via the MEK/ERK signaling pathway. In addition, our findings strongly indicate that DBD-F can inhibit HIF2α expression by affecting the phosphorylation status of MEK/ERK in gastric cancer-derived cells.

HIF2α is associated with poor prognosis and affects the expression levels of survivin and cyclin D1 in gastric carcinoma.

Hypoxia-inducible factor-2α (HIF2α) is a major determinant factor of invasion and metastasis in various tumors. It has been reported that HIF2α is overexpressed in many tumors, including gastric cancer. However, the roles of HIF2α in the progression of gastric cancer are still not clear. In this study, we first examined the levels of HIF2α in gastric cancer by using immunohistochemistry, western blot and real-time PCR analysis. The results showed that HIF2α was highly expressed in gastric cancers compared to non-neoplastic mucosa and significantly correlated with histologic grade, TNM stages and peritoneal dissemination. MTT and colony formation assay revealed HIF2α overexpression induced high proliferation in BGC823 cells and HIF2α knockdown significantly inhibited proliferation in SGC7901 cells. Furthermore, we demonstrated that HIF2α could promote migration and invasion in gastric cancer cells. The results of western blot and RT-PCR analysis indicated that Survivin, Cyclin D1, MMP2 and MMP9 are upregulated with HIF2α overexpression. Finally, similar roles of HIF2α also in vivo were demonstrated. Taken together, the present study suggested that HIF-2α was involved in proliferation, metastasis and invasion of gastric cancer cells, with the induction of Survivin, Cyclin D1, MMP2 and MMP9 expression.