Elevated expression of APE1/Ref-1 and its regulation on IL-6 and IL-8 in bone marrow stromal cells of multiple myeloma.

A number of growth factors secreted by bone marrow stromal cells (BMSCs), including interleukin-6 and -8 (IL-6/8), are important for the initiation and progression of multiple myeloma (MM). However, the mechanisms that regulate the production of IL-6/8 by BMSC have not yet been well characterized. Human dual functional protein apurinic/apyrimidinic endonuclease-1/redox factor-1 (APE1/Ref-1) is essential for cell survival and proliferation.

Microarray analysis of DNA damage repair gene expression profiles in cervical cancer cells radioresistant to 252Cf neutron and X-rays.

Background: The aim of the study was to obtain stable radioresistant sub-lines from the human cervical cancer cell line HeLa by prolonged exposure to 252Cf neutron and X-rays. Radioresistance mechanisms were investigated in the resulting cells using microarray analysis of DNA damage repair genes.

Methods: HeLa cells were treated with fractionated 252Cf neutron and X-rays, with a cumulative dose of 75 Gy each, over 8 months, yielding the sub-lines HeLaNR and HeLaXR.

Targeting truncated APE1 in mitochondria enhances cell survival after oxidative stress.

The high steady-state level of mitochondrial DNA (mtDNA) oxidative lesions is assumed to be the result of high susceptibility to DNA damage attack and limited DNA repair capacity in mitochondria. As a key enzyme of base excision repair (BER), human apurinic/apyrimidinic endonuclease (APE1) is often scarce in mitochondria, and mitochondria-targeted APE1 with robust repair activity represents a promising therapeutic candidate. In this study, overexpression vectors of mitochondria-targeted truncated APE1 (mtAPE1) and that of full-length APE1 (flAPE1) were constructed and transfected to human umbilical vein endothelial cells to test their protective effects after hydrogen peroxide-induced oxidative stress.