Compared with healthy controls, GP73 in patients with liver disease was significantly increased. With the progression of liver disease, GP73 showed a significantly increasing trend. These results suggest that GP73 might be used as a serum marker for the diagnosis of liver diseases and for monitoring disease progression.

The dysregulated ERK and RB pathways often coexist in melanoma cells. The K-type human endogenous retrovirus (HERV-K) is implicated in melanomagenesis. Some of the phenotypes that are modified by HERV-K (e.g., changes in cell shape, melanin production, and anchorage-dependent growth) overlap with those that are regulated by ERK and RB pathways. As ERK signaling can regulate retroviruses, we hypothesized that HERV-K expression is controlled by ERK-RB pathways. We found that the levels of HERV-K GAG and EVE correlated with the activation of ERK and loss of p16INK4A and that inhibition of MEK or CDK4, especially in combination, reduced HERV-K EVE in melanoma cells.

Amplification of the EGFR gene and its truncation mutant EGFRvIII are hallmarks of glioblastoma. Although co-expression of EGFR and EGFRvIII confers a growth advantage, how EGFR and EGFRvIII influence the tumor microenvironment remains incompletely understood. Here we show that EGFR and EGFRvIII cooperate to induce macrophage infiltration via upregulation of the chemokine CCL2. EGFRvIII was significantly enriched in glioblastoma patient samples with high CCL2, and knockout of CCL2 in tumors co-expressing EGFR and EGFRvIII led to decreased infiltration of macrophages. KRAS was a critical signaling intermediate for EGFR and EGFRvIII-induced expression of CCL2. Our results illustrate how EGFR and EGFRvIII direct the microenvironment in glioblastoma.

Introduction and Hypothesis:Nuclear atypia with features of multi nuclei have been detected in human melanoma specimens. We found that the K type human endogenous retroviral element (HERV K) is expressed in such cells. Since cellular syncytia can form when cells are infected with retroviruses, we hypothesized that HERV K expressed in melanoma cells may contribute to the formation of multinuclear atypia cells in melanoma.Experiments and Results:We specifically inhibited HERV K expression using RNA interference (RNAi) and monoclonal antibodies and observed dramatic reduction of intercellular fusion of cultured melanoma cells. Importantly, we identified loss of heterozygosity (LOH)of D19S433 in a cell clone that survived and proliferated after cell fusion.Conclusion:Our results support the notion that proteins encoded by HERV K can mediate intercellular fusion of melanoma cells, which may generate multinuclear cells and drive the evolution of genetic changes that provide growth and survival advantages.