Cancer Res 2007, 67: 2517–2525.PubMedCrossRef 20. Gosepath EM, Eckstein N, Hamacher A, Servan K, von Jonquieres G, Lage H, Györffy B, Royer HD, Kassack MU: Acquired cisplatin resistance in the head-neck cancer cell line Cal27 is associated with decreased selleck screening library DKK1 expression and can partially be reversed by overexpression of DKK1. Int J Cancer 2008, 123: 2013–2019.PubMedCrossRef 21. Mueller W, Lass U, Wellmann S, Kunitz F, von Deimling

A: Mutation analysis of DKK1 and in vivo evidence of predominant p53-independent DKK1 function in gliomas. Acta Neuropathol (Berl) 2005, 109: 314–320.CrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions YZ conceived of the study, and participated

in its design and coordination and helped to draft the manuscript. WL carried out the molecular genetic studies. QX participated in its design and coordination. YH participated in the conception and the design of the analysis. All authors read and approved the final manuscript”
“Background Hepatocellular carcinoma (HCC) is the fifth most frequent cancer and the third leading cause of cancer death worldwide, with over a half million SP600125 mw mortality every year [1]. HCC is also common in China. The recent report for annual incidence and mortality in China were 300,000 and 306,000 selleck chemicals llc cases [2, 3]. This disease is strongly associated with several risk factors, including chronic hepatitis B virus (HBV) and chronic hepatitis C virus (HCV) infection, and alcohol abuse [4]. HBV infection is a challenging Carnitine palmitoyltransferase II health issue in China, where about 93 million peoples are HBV carriers and 30 million have chronic B hepatitis [5]. Alcohol abuse is also on the rise in China and about 6.6% of males and 0.1% of females are diagnosed with alcohol dependence [6]. Many of

these patients develop liver diseases, such as alcoholic hepatitis and cirrhosis, which are prone to HCC. Hepatitis virus infection and alcohol abuse are associated with increased oxidative stress in liver cells, resulting in DNA changes including mitochondrial DNA (mtDNA) instability [7, 8]. The human mitochondrial genome is 16 kb in length and a closed-circular duplex molecule that contains 37 genes, including two ribosomal RNAs and complete set of 22 tRNAs [9]. mtDNA is believed to be more susceptible to DNA damage and acquires mutations at a higher rate than nuclear DNA because of high levels of reactive oxygen species (ROS), lack of protective histones, and limited capacity for DNA repair in mitochondria [10–12]. Thus, somatic mtDNA mutations occur in a wide variety of degenerative diseases and cancers [13, 14], and can be homoplasmic by clonal expansion [15, 16] or heteroplasmic in tumor tissues [17, 18].