Targeting the interaction of ß-catenin and TCF/LEF transcription factors to inhibit oncogenic Wnt signaling.

The Wnt/ß-catenin signaling pathway is crucially involved in embryonic development, stem cell maintenance and tissue renewal. Hyperactivation of this pathway is associated with the development and progression of various types of cancers. The transcriptional coactivator ß-catenin represents a pivotal component of the pathway and its interaction with transcription factors of the TCF/LEF family is central to pathway activation. Inhibition of this crucial protein-protein interaction via direct targeting of ß-catenin is considered a promising strategy for the inactivation of oncogenic Wnt signaling. This review summarizes advances in the development of Wnt antagonists that have been shown to directly bind ß-catenin.

Prospective pilot trial of calcipotriene as a novel topical treatment for acute skin graft versus host disease.

Skin graft versus host disease (GVHD) can affect quality of life in hematopoietic stem cell transplant recipients. Therapeutic options for steroid-refractory GVHD are limited. We report the first prospective pilot study evaluating the topical vitamin D3 analog Calcipotriene (DOVONEX 0.005% cream) for acute skin GVHD in children, with associated analyses of target organ chemokine CXCL10 changes in response to therapy. We observed that Calcipotriene applications were safe and well tolerated. There were no symptom progression nor new symptoms requiring GVHD therapy escalation during study period. The most consistent response observed by study subjects was resolution of pruritus in eight patients and significant improvement in pruritus in two study subjects. Nine of ten patients had improvement or resolution of skin rash. In addition, we documented reduction of CXCL10 levels in the skin of seven subjects with GVHD after Calcipotriene course using non-invasive D-Squame® disc application to the skin for chemokine analysis. Our pilot study shows promising observation that topical Calcipotriene could be a novel therapeutic option for acute skin GVHD, especially in patients presenting with pruritus and should be studied in larger prospective studies.

NUPR1, a new target in liver cancer: implication in controlling cell growth, migration, invasion and sorafenib resistance.

Sorafenib, an oral multikinase inhibitor, is the only approved agent for the treatment of advanced hepatocellular carcinoma (HCC). However, its benefits are modest, and as its mechanisms of action remain elusive, a better understanding of its anticancer effects is needed. Based on our previous study results, we investigated here the implication of the nuclear protein 1 (NUPR1) in HCC and its role in sorafenib treatment. NUPR1 is a stress-inducible protein that is overexpressed in various malignancies, but its role in HCC is not yet fully understood. We found that NUPR1 expression was significantly higher in primary human HCC samples than in the normal liver. Knockdown of NUPR1 significantly increased cell sensitivity to sorafenib and inhibited the cell growth, migration and invasion of HCC cells, both in vitro and in vivo. Moreover, NUPR1 silencing influenced the expression of RELB and IER3 genes. Unsurprisingly, RELB and IER3 knockdown also inhibited HCC cell viability, growth and migration. Using gene expression profiling of HCC cells following stable NUPR1 knockdown, we found that genes functionally involved in cell death and survival, cellular response to therapies, lipid metabolism, cell growth and proliferation, molecular transport and cellular movement were mostly suppressed. Network analysis of dynamic gene expression identified NF-κB and ERK as downregulated gene nodes, and several HCC-related oncogenes were also suppressed. We identified Runt-related transcription factor 2 (RUNX2) gene as a NUPR1-regulated gene and demonstrated that RUNX2 gene silencing inhibits HCC cell viability, growth, migration and increased cell sensitivity to sorafenib. We propose that the NUPR1/RELB/IER3/RUNX2 pathway has a pivotal role in hepatocarcinogenesis. The identification of the NUPR1/RELB/IER3/RUNX2 pathway as a potential therapeutic target may contribute to the development of new treatment strategies for HCC management.