The HLJ1-targeting drug screening identified Chinese herb andrographolide that cansuppress tumour growth and invasion in non-small-cell lung cancer

HLJ1 is a novel tumour suppressor and is a potential druggable target for non-small-cell lung cancer (NSCLC). In this report, using a promoter-containing enhancer region as the HLJ1-targeting drug-screening platform, we identified several herbal compounds from a Chinese herbal bank with the capacity to enhance HLJ1 promoter activity and suppress tumour growth and invasion of NSCLC. Among the herbal drugs identified, the andrographolide (from Andrographis paniculata [Burm. f.] Nees.) most significantly induced HLJ1 expression and suppressed tumorigenesis both in vitro and in vivo. The andrographolide upregulates HLJ1 via JunB activation, which modulates AP-2α binding at the MMP-2 promoter and represses the expression of MMP-2. In addition, silencing of HLJ1 partially reverses the inhibition of cancer-cell invasion by andrographolide. Microarray transcriptomic analysis was performed to comprehensively depict the andrographolide-regulated signalling pathways. We showed that andrographolide can affect 939 genes (analysis of variance, false discovery rate < 0.05) that are dominantly involved in the cell cycle, apoptosis and adhesion-related biological signalling, including mitogen-activated protein kinase, focal adhesion and tight junction pathways, indicating the diverse effects of andrographolide on anticancer invasion and proliferation. In conclusion, the HLJ1-targeting drug-screening platform is useful for screening of novel anticancer compounds. Using this platform, we identified andrographolide is a promising new anticancer agent that could suppress tumour growth and invasion in NSCLC

A Novel Function of YWHAZ/b-Catenin Axis in Promoting Epithelial–Mesenchymal Transition and Lung Cancer Metastasis

YWHAZ, also known as 14-3-3zeta, has been reportedly elevated in many human tumors, including non–small cell lung carcinoma (NSCLC) but little is known about its specific contribution to lung cancer malignancy. Through a combined array-based comparative genomic hybridization and expression microarray analysis, we identified YWHAZ as a potential metastasis enhancer in lung cancer. Ectopic expression of YWHAZ on low invasive cancer cells showed enhanced cell invasion, migration in vitro, and both the tumorigenic and metastatic potentials in vivo. Gene array analysis has indicated these changes associated with an elevation of pathways relevant to epithelial–mesenchymal transition (EMT), with an increase of cell protrusions and branchings. Conversely, knockdown of YWHAZ levels with siRNA or short hairpin RNA (shRNA) in invasive cancer cells led to a reversal of EMT. We observed that high levels of YWHAZ protein are capable of activating b-catenin–mediated transcription by facilitating the accumulation of b-catenin in cytosol and nucleus. Coimmunoprecipitation assays showed a decrease of ubiquitinated b-catenin in presence of the interaction between YWHAZ and b-catenin. This interaction resulted in disassociating b-catenin from the binding of b-TrCP leading to increase b-catenin stability. Using enforced expression of dominant-negative and -positive b-catenin mutants, we confirmed that S552 phosphorylation of b-catenin increases the b-catenin/YWHAZ complex formation, which is important in promoting cell invasiveness and the suppression of ubiquitnated b-catenin. This is the first demonstration showing YWHAZ through its complex with b-catenin in mediating lung cancer malignancy and b-catenin protein stability

Recombinant Lipidated HPV E7 Induces a Th-1-Biased Immune Response and Protective Immunity against Cervical Cancer in a Mouse Model

The E7 oncoprotein of human papillomavirus (HPV) is an ideal target for developing immunotherapeutic strategies against HPV-associated tumors. However, because protein-based immunogens alone are poor elicitors of the cytotoxic Tlymphocyte (CTL) responses, they have been difficult to exploit for therapeutic purposes. In this study, we report that a recombinant lipoprotein consisting of inactive E7 (E7m) biologically linked to a bacterial lipid moiety (rlipo-E7m) induces the maturation of mouse bone marrow-derived dendritic cells through toll-like receptor 2 (TLR2), skews the immune responses toward the Th1 responses and induces E7-specific CTL responses. We further studied the ability of rlipo-E7m to provide protection against a TC-1 tumor cell challenge in an animal model. Mice prophylactically immunized with two 10-mg doses of rlipo-E7m were found to be free of TC-1 tumor growth. Experiments in a therapeutic immunization model showed that the tumor volume in mice receiving a single dose of rlipo-E7m was less than 0.01 cm3 on day 40, whereas the tumor volume in mice treated with rE7m was 2.2861.21 cm3. The tumor volume of the entire control group was over 3 cm3. In addition, we demonstrated that the CD8+ T cells play a major role in anti-tumor immunity when administration of rlipo- E7m. These results demonstrate that rlipo-E7m could be a promising candidate for treating HPV-associated tumors

Spermine Attenuates the Action of the DNA Intercalator, Actinomycin D, on DNA Binding and the Inhibition of Transcription and DNA Replication

The anticancer activity of DNA intercalators is related to their ability to intercalate into the DNA duplex with high affinity, thereby interfering with DNA replication and transcription. Polyamines (spermine in particular) are almost exclusively bound to nucleic acids and are involved in many cellular processes that require nucleic acids. Until now, the effects of polyamines on DNA intercalator activities have remained unclear because intercalation is the most important mechanism employed by DNA-binding drugs. Herein, using actinomycin D (ACTD) as a model, we have attempted to elucidate the effects of spermine on the action of ACTD, including its DNA-binding ability, RNA and DNA polymerase interference, and its role in the transcription and replication inhibition of ACTD within cells. We found that spermine interfered with the binding and stabilization of ACTD to DNA. The presence of increasing concentrations of spermine enhanced the transcriptional and replication activities of RNA and DNA polymerases, respectively, in vitro treated with ActD. Moreover, a decrease in intracellular polyamine concentrations stimulated by methylglyoxal-bis(guanylhydrazone) (MGBG) enhanced the ACTDinduced inhibition of c-myc transcription and DNA replication in several cancer cell lines. The results indicated that spermine attenuates ACTD binding to DNA and its inhibition of transcription and DNA replication both in vitro and within cells. Finally, a synergistic antiproliferative effect of MGBG and ACTD was observed in a cell viability assay. Our findings will be of significant relevance to future developments in combination with cancer therapy by enhancing the anticancer activity of DNA interactors through polyamine depletion