Quinone oxidoreductase 1 is overexpressed in gastric cancer and associated with outcome of adjuvant chemotherapy and survival.

Background: Quinine oxidoreductase 1 (NQO1) plays a vital role in protecting normal cells against oxidative damage and electrophilic attack. It is highly expressed in many solid tumors, suggesting a role in cancer development and progression. However, the role of NQO1 in gastric cancer and its effect on cancer development and prognosis have not been fully investigated.

Luteolin sensitizes two oxaliplatin-resistant colorectal cancer cell lines to chemotherapeutic drugs via inhibition of the Nrf2 pathway.

Oxaliplatin is a first-line therapy for colorectal cancer, but cancer cell resistance to the drug compromises its efficacy. To explore mechanisms of drug resistance, we treated colorectal cancer cells (HCT116 and SW620) long-term with oxaliplatin and established stable oxaliplatin-resistant lines (HCT116-OX and SW620-OX). Compared with parental cell lines, IC50s for various chemotherapeutic agents (oxaliplatin, cisplatin and doxorubicin) were increased in oxaliplatin-resistant cell lines and this was accompanied by activation of nuclear factor erythroid-2 p45-related factor 2 (Nrf2) and NADPH quinone oxidoreductase 1 (NQO1).

[Nrf2 as a chemoprevention target in gastrointestinal carcinoma].

Gastrointestinal tract carcinoma is one of the leading causes of cancer-related death in China. Chemoprevention has been considered as a potential approach to control this type of disease. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a redox-sensitive transcription factor that protects cells from oxidative/electrophilic stresses by activating the expression of a battery of cytoprotective genes through the antioxidant response element (ARE).

[Research progress on MKP-1 in tumor drug resistance].

The main obstacle for chemotherapy is tumor drug resistance. Studying the mechanisms of drug resistance and reversing drug resistance is the key to improve the effectiveness of chemotherapy. It has been reported that MKP-1 plays an important role in tumor drug resistance.

[Anti-proliferation and chemo-sensitization effects of apigenin on human lung cancer cells].

Objective: To investigate the antitumor effect of apigenin on human lung cancer cells.

Methods: The anti-proliferation and sensitization effects of apigenin on human lung cancer cells was accessed by counting cells after Trypan blue staining and MTS assay.

Results: (1) Apigenin significantly suppressed the proliferation of four types of human lung cancer cells (A549:P=0.

[Study on the optical properties of semiconductor nanocrystalline powder using photoacoustic technology].

The optical properties of semiconductor nanocrystalline powder were studied by using photoacoustic spectroscopy technique. The band gap and the optical absorption coefficient of semiconductor nanocrystalline powder of TiO2, ZnO and Al-doped ZnO were measured by normalized photoacoustic spectroscopy technique. The results show that the optical properties of semiconductor nanocrystalline powder relate to particle size and particle shape.

[Effect of Luteolin and its combination with chemotherapeutic drugs on cytotoxicity of cancer cells].

Objective: To investigate the effect of Luteolin alone or combination with chemotherapentic drugs on the cytoxicity of cancer cells.

Methods: Cultured A549, Hela, MCF-7, AGS, MGC-803, Caco2 and HepG2 cells were treated with Luteolin or the combination of Luteolin with other chemotherapeutic agents (Bexarotene, Cisplatin and Bleomycin). Cell viability was measured by MTS assay and IC(50) was calculated.

[Effect of DRB/alpha-Amanitin on localization of Nrf2 in A549 cells].

Objective: To investigate the effects of transcriptional inhibitors 5, 6-dichloro-1-b-D-ribofuranosylbenzimidazole (DRB) and alpha-Amanitin on the localization of Nrf2 in the nucleus.

Methods: A549 cells were treated with DRB (50 mg/L) or alpha-Amanitin (2.5 mg/L)for 1 h and 6 h in serum-free medium, respectively.

[Effect of tBHQ and sulforaphane on Nrf2-ARE signaling pathway of Caco2 cells].

Objective: To investigate the effect of tBHQ and sulforaphane on the protein expression in Nrf2-ARE signaling pathway of Caco2 cells.

Methods: Human colorectal carcinoma Caco2 cells were treated with 20 micromol/L tBHQ and 5 micromol/L sulforaphane (SFN) respectively. Real time PCR, Western blotting and immunoflourescence staining (IF) were performed to measure the target gene expression.

[Nrf2 down-regulated cell line H460-N5 with Keap1 over-expression increased sensitivity to anti-cancer drugs].

Objective: To maked a Nrf2 down-regulated cell line by over-expressing Keap1 in H460 cells to study the role of Nrf2 in drug resistance.

Methods: Transfecting H460 cells with mKeap1-pEGFP and screenig for Keap1 expressing clones by Western blotting with antibodies against Nrf2, HO-1, NQO1 and AKR1C. The cell line with Keap1 over-expression was further confirmed by real-time PCR.