Sulforaphane suppresses carcinogenesis of colorectal cancer through the ERK/Nrf2­UDP glucuronosyltransferase 1A metabolic axis activation.

The long pre­cancerous state of colorectal cancer (CRC) provides an opportunity to prevent the occurrence and development of CRC. The detoxification of CRC food­borne carcinogenic heterocyclic amines is highly dependent on UDP glucuronosyltransferase 1A (UGT1A)­mediated glucuronidation. Sulforaphane (SFN), a phytochemical, possesses antioxidant, anti­inflammatory and anticarcinogenic effects on the prevention of CRC. Previous studies revealed that SFN upregulates the expression of UGT1A. The aim of the present study was to investigate the regulatory mechanism of SFN­induced UGT1A upregulation and provide novel understanding on the basic research and chemoprevention of CRC. In the present study, the viability and proliferation of CRC cells (HT­29 and SW480) treated with SFN were assessed by MTT, colony formation and EdU assays. Flow cytometry was used to detect the cell cycle arrest and apoptosis of cells treated with different concentrations of SFN. The motility of cells was determined by wound healing and Transwell assays. Nuclear factor, erythroid 2 like 2 (Nrf2) short hairpin RNA (shRNA) and negative control shRNA lentiviruses were used for cell transfection. Reverse transcription­quantitative polymerase chain reaction and western blotting were employed to verify the role of Nrf2 in SFN­induced UGT1A. HT­29 and SW480 cells were divided into a control, an SFN and a PD98059 [an extracellular signal­regulated kinase (ERK) inhibitor] + SFN group. Western blotting detected the protein levels of Nrf2 and UGT1A. Intracellular levels of reactive oxygen species (ROS) were detected using a reactive oxygen assay kit. The results revealed that SFN inhibits cell proliferation and colony formation, promotes apoptosis, and reduces the migratory ability of CRC cells. The phosphorylation of ERK induced by SFN promoted Nrf2 accumulation. Furthermore, a significant increase in the levels of UGT1A was observed, which coincided with SFN­induced upregulation of Nrf2 levels in nuclear fractions. Pretreatment with PD58059 reversed the SFN­induced subcellular translocation of Nrf2 and the expression of UGT1A. In addition, SFN­induced high levels of ROS in CRC cells may be associated with the ERK signaling pathway. Collectively, these results indicated that SFN inhibited the proliferation of CRC cells and upregulated the expression of UGT1A in CRC cells via the ERK/Nrf2 signaling pathway.

Sulforaphane-induced epigenetic regulation of Nrf2 expression by DNA methyltransferase in human Caco-2 cells.

The present study aimed to investigate the mechanism underlying sulforaphane-mediated epigenetic regulation of nuclear factor-erythroid derived 2-like 2 (Nrf2) expression in human colon cancer. Proteins were extracted from normal Caco-2 cells using sulforaphane and 5-aza-2'-deoxycytidine (5-Aza) combined with trichostatin A (TSA). The mRNA and protein expression levels and activity of DNA methyltransferase 1 (DNMT1) were determined. Methylation-specific polymerase chain reaction and bisulfite genomic sequencing were also used to measure the methylation levels of CpG sites in the Nrf2 promoter region. Nrf2 expression was measured using reverse transcription-quantitative PCR and western blot analysis. The results demonstrated that sulforaphane did not affect DNMT1 mRNA expression levels. DNMT1 protein expression was inhibited by sulforaphane and 5-Aza co-treatment with TSA. Nrf2 promoter methylation decreased significantly in the sulforaphane group compared with the control group. Nrf2 promoter methylation level in the 5-Aza+TSA group was the lowest among all groups. Nrf2 mRNA levels exhibited significant differences between the sulforaphane-treated and control groups, as well as between the 5-Aza+TSA and control groups, and the sulforaphane-treated and 5-Aza+TSA groups. Nrf2 protein expression was also inhibited by sulforaphane, as well as 5-Aza co-treatment with TSA. The results revealed that sulforaphane may promote demethylation of the Nrf2 promoter region to increase activation of Nrf2, which induces chemoprevention of colon cancer.

Screening and application of nutritional support in elderly hospitalized patients of a tertiary care hospital in China.

BACKGROUND: Malnutrition is very common in elderly patients admitted to the hospital. The aim of our study is to assess the nutritional status of elderly patients and the use of nutritional support in a tertiary care hospital in China and to analyze the impacts of nutritional status and nutritional support on clinical outcomes. METHODS: Statistical analysis was performed on a sample of 745 elderly patients in the geriatric medicine department of Qilu Hospital of Shandong University from March 2012 to March 2015. The Nutrition Risk Screening 2002 (NRS 2002) and Mini Nutritional Assessment-short forms (MNA-SF) were utilized for the nutritional risk screening at admission. Personal information, anthropometric measurements, laboratory tests, nutritional support and clinical outcomes were recorded. Comparisons were carried out to analyze impacts on clinical outcomes and prognosis based on incidence rate of nutritional risk, nutritional support rate, and different methods of support. RESULTS: NRS 2002 and MNA-SF were utilized to screen for nutritional risk at admission. The results of this screening were 39.81% and 44.10%, respectively. Based on the results of the MNA-SF, 33.38% of elderly patients were at risk of malnutrition and 5.5% were malnourished. The incidence of nutritional risk in the departments of Gastroenterology, Hematology, and Respiratory were 51.72%, 46.88%, 43.33%, respectively, higher than in other departments. Patients with nutritional risk were more likely to have a longer hospital stay compared to those without (P < 0.05). The nutritional support rate of patients overall was 16.49%, and the ratio of Parenteral nutrition (PN):Enteral nutrition (EN) was 5.13:1. Patients at nutritional risk had an in-hospital support rate of 29.63% and 28.57%, respectively, identified via screening by NRS 2002 and MNA-SF. Nutritional support rate of patients without nutritional risk was 7.8%(35/449) and 6.96%(29/417), respectively. Patients in the departments of Gastroenterology and Hematology had higher rates of nutritional support than patients in other departments. In addition, results showed that in patients with nutritional risk and malnutrition, nutritional support decreased the length of hospital stay (P<0.05). The patients that received nutritional support also had a lower incidence of infectious complications than the patients without nutritional support (NRS 2002 was 6.82%:18.18% and MNA-SF was 9.57%:20.23%)(P<0.05). CONCLUSIONS: Undernourishment and nutritional risk in elderly patients at hospital admission is a common occurrence. In the current study, the nutritional risk rate in the Gastroenterology department was higher than in other departments. Patients with normal nutritional status were still receiving nutritional support. Overall, there is a need to better apply nutritional support in the clinical treatment of elderly patients. In elderly patients with nutritional risk and malnutrition, nutritional support reduced the length of hospital stay and the incidence of infectious complications.