Chi-Chung Wang

Curcumin inhibits lung cancer cell invasion and metastasis through the tumor suppressor HLJ1.

Curcumin (diferuloylmethane) is an active component of the spice turmeric and has a diversity of antitumor activities. In this study, we found that curcumin can inhibit cancer cell invasion and metastasis through activation of the tumor suppressor DnaJ-like heat shock protein 40 (HLJ1). Human lung adenocarcinoma cells (CL1-5) treated with curcumin (1-20 mumol/L) showed a concentration-dependent reduction in cell migration, invasion, and metastatic ability, and this was associated with increased HLJ1 expression. Knockdown of HLJ1 expression by siRNA was able to reverse the curcumin-induced anti-invasive and antimetastasis effects in vitro and in vivo. The HLJ1 promoter and enhancer in a luciferase reporter assay revealed that curcumin transcriptionally up-regulates HLJ1 expression through an activator protein (AP-1) site within the HLJ1 enhancer. JunD, one of the AP-1 components, was significantly up-regulated by curcumin (1-20 mumol/L) in a concentration- and time-dependent manner. Knockdown of JunD expression could partially reduce the curcumin-induced HLJ1 activation and diminish the anti-invasive effect of curcumin, indicating that JunD would seem to be involved in curcumin-induced HLJ1 expression. Curcumin was able to induce c-Jun NH(2)-kinase (JNK) phosphorylation, whereas the JNK inhibitor (SP-600125) could attenuate curcumin-induced JunD and HLJ1 expression. Activation of HLJ1 by curcumin further leads to up-regulation of E-cadherin and a suppression of cancer cell invasion. Our results show that curcumin induces HLJ1, through activation of the JNK/JunD pathway, and inhibits lung cancer cell invasion and metastasis by modulating E-cadherin expression. This is a novel mechanism and supports the application of curcumin in anti-cancer metastasis therapy.

Dimethyl sulfoxide promotes the multiple functions of the tumor suppressor HLJ1 through activator protein-1 activation in NSCLC cells.

Background Dimethyl sulfoxide (DMSO) is an amphipathic molecule that displays a diversity of antitumor activities. Previous studies have demonstrated that DMSO can modulate AP-1 activity and lead to cell cycle arrest at the G1 phase. HLJ1 is a newly identified tumor and invasion suppressor that inhibits tumorigenesis and cancer metastasis. Its transcriptional activity is regulated by the transcription factor AP-1. However, the effects of DMSO on HLJ1 are still unknown. In the present study, we investigate the antitumor effects of DMSO through HLJ1 induction and demonstrate the mechanisms involved. Methods and Findings Low-HLJ1-expressing highly invasive CL1–5 lung adenocarcinoma cells were treated with various concentrations of DMSO. We found that DMSO can significantly inhibit cancer cell invasion, migration, proliferation, and colony formation capabilities through upregulation of HLJ1 in a concentration-dependent manner, whereas ethanol has no effect. In addition, the HLJ1 promoter and enhancer reporter assay revealed that DMSO transcriptionally upregulates HLJ1 expression through an AP-1 site within the HLJ1 enhancer. The AP-1 subfamily members JunD and JunB were significantly upregulated by DMSO in a concentration-dependent manner. Furthermore, pretreatment with DMSO led to a significant increase in the percentage of UV-induced apoptotic cells. Conclusions Our results suggest that DMSO may be an important stimulator of the tumor suppressor protein HLJ1 through AP-1 activation in highly invasive lung adenocarcinoma cells. Targeted induction of HLJ1 represents a promising approach for cancer therapy, which also implied that DMSO may serve as a potential lead compound or coordinated ligand for the development of novel anticancer drugs.

The HLJ1-targeting drug screening identified Chinese herb andrographolide that can suppress 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.

Tumour suppressor HLJ1: A potential diagnostic, preventive and therapeutic target in non-small cell lung cancer.

Lung cancer is the leading cause of cancer-related mortality throughout the world. Non-small cell lung cancer (NSCLC) accounts for 85% of all diagnosed lung cancers. Despite considerable progress in the diagnosis and treatment of the disease, the overall 5-year survival rate of NSCLC patients remains lower than 15%. The most common causes of death in lung cancer patients are treatment failure and metastasis. Therefore, developing novel strategies that target both tumour growth and metastasis is an important and urgent mission for the next generation of anticancer therapy research. Heat shock proteins (HSPs), which are involved in the fundamental defence mechanism for maintaining cellular viability, are markedly activated during environmental or pathogenic stress. HSPs facilitate rapid cell division, metastasis, and the evasion of apoptosis in cancer development. These proteins are essential players in the development of cancer and are prime therapeutic targets. In this review, we focus on the current understanding of the molecular mechanisms responsible for HLJ1s role in lung cancer carcinogenesis and progression. HLJ1, a member of the human HSP 40 family, has been characterised as a tumour suppressor. Research studies have also reported that HLJ1 shows promising dual anticancer effects, inhibiting both tumour growth and metastasis in NSCLC. The accumulated evidence suggests that HLJ1 is a potential biomarker and treatment target for NSCLC.

Abstract 1431: Id4 inhibits cancer metastasis through EMT regulation in lung cancer

Lung cancer is the leading cause of cancer related deaths worldwide. Delayed diagnosis and early metastasis are the major unsolved obstacles for most physicians in treating lung cancer patients. Thus, identifying novel metastatic genes and their action mechanisms involved in lung cancer progression and metastasis may provide new insights into the pathogenesis and management of lung cancer treatment. In a previous genome-wide gene expression profiling analysis using an invasion cancer cell lines model, we identified a panel of 589 genes whose expression was correlated with cell invasiveness. And Inhibitor of DNA binding 4 (Id4) was one of these candidates. In this study, we demonstrate that the expression of Id4 was inversely associated with cell invasiveness in different lung cancer cell lines. Through manipulating the expression of Id4, we found that the expression of Id4 not only attenuate cell migration and invasion in vitro, but also affect the regulation of Epithelial-mesenchymal transition (EMT), a critical step for cancer metastasis. Additionally, we demonstrated that the expression Id4 was inversely correlated with lung cancer metastasis in vitro and in vivo and the reason Id4 affects metastasis probably is the regulation of EMT procession. Our data showed that Id4 could regulate EMT pathway by controlling the expression of Slug, a well-known EMT regulator, and recovering promoter activity of E-cadherin. Collectively, Id4 is a tumor suppressor in lung cancer, it can down-regulate EMT by reversing E-cadherin expression that represses by Slug. How to translate this research result for clinical application and develop potential therapeutic strategy for lung cancer treatment is our work in the future. Citation Format: Szu-Hua Pan, Yuan Ling Hsu, Pei-Fang Hung, Chia-Jen Wang, Chi-Chung Wang. Id4 inhibits cancer metastasis through EMT regulation in lung cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1431. doi:10.1158/1538-7445.AM2015-1431

Abstract 4183: Overexpression of PTPN2 promotes lung cancer cell proliferation through ERK activation

Lung cancer is the most common cause of cancer deaths in the world, and the incidence is increasing each year. Protein tyrosine phosphatases (PTPs) and their associated signaling pathways are crucial for the regulation of numerous cell functions including growth, motility, mitogenesis and metabolism. PTPN2, also known as TCPTP, is an intracellular protein tyrosine phosphatase, which is ubiquitously expressed. There are two splice variants of TCPTP in human cells, TC45 and TC48, which vary at their C-terminal ends. The TC48 isoform is present in the endoplasmic reticulum and also in the nuclear membrane. However, its role and function on human non-small cell lung cancers remain unknown. In this study, we induced ectopic expression of PTPN2 (TC48) in CL1-0 and H1299 cells to investigate its effect on cell migration, invasion, and colony formation. The interacting proteins of PTPN2 are identified by yeast two-hybrid assay. The results showed that PTPN2 inhibited lung cancer cell proliferation, anchorage-dependent and -independent growth, but not migration and invasion. Yeast two-hybrid assay revealed that PTPN2 interacted with CD74 (major histocompatibility complex class II invariant chain) and PRDX6 (Peroxiredoxin 6) which could promote cell proliferation in previous studies. We also found that overexpression of PTPN2 increased the phosphorylation of ERK. Moreover, activation of ERK was enhanced by co-expression of PTPN2 and CD74 or PRDX6. Taken together, we speculated that PTPN2 might modulate ERK activity through interaction with CD74 and PRDX6 and further promoted lung cancer cell proliferation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4183. doi:1538-7445.AM2012-4183

Abstract 4320: Overexpression of Homeobox A5 decreases the invasive and migration capabilities of lung cancer cells

Homeobox genes are a family of regulatory genes containing a common homeobox and act as transcription factors. Many cancers exhibit unusual alteration and expression in homeobox genes, including leukemia, colon, skin, prostate, breast, and ovary cancers. Recent studies indicated that homeobox A5 (HOXA5) may behave as a tumor suppressor gene in breast cells. However, the real roles of HOXA5 in lung cancer remains to be further clarified. In this study, we investigated the effect of HOXA5 on the invasive ability of more invasive CL1-5 cells transfected with HOXA5 constitutively expressed system. The results revealed that the excessive expression of HOXA5 can inhibit tumor cell invasion and migration capabilities. In addition, the HOXA5 specific siRNA could restore these effects. The results of metastatic analysis in SCID mice also demonstrated that HOXA5-overexpressed transfectants could decrease in vivo tumor nodule numbers. Furthermore, the HOXA5 mRNA expression was measured by real time RT-PCR in NSCLC surgical specimens and correlated with the patients’ clinical outcome. The HOXA5 downstream genes and HOXA5-regulated pathways were identified by using Affymetrix microarray and CRSD bioinformatics platform built in-house. Our studies herein provide a new insight into how HOXA5 may contribute to tumor metastasis inhibition in lung cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4320. doi:1538-7445.AM2012-4320

Abstract 2188: Effect of the protein complex formation of a novel tumor suppressor HLJ1 and nuclear protein p54nrb on human lung adenocarcinoma cell migration and invasion

Lung cancer is the most common cause of cancer deaths in the world, and the incidence is increasing each year. In the previous studies, we have identified and characterized a novel tumor/invasion suppressor gene HLJ1 (human liver DnaJ-like protein, also called DNAJB4) in a lung cancer cell line model with different invasion capability. However, the suppressive mechanism of HLJ1 is unclear. Therefore, the objective of this study is to investigate and characterize the proteins interacting with HLJ1. To obtain the novel HLJ1-binding protein, the differentially cultured density of tumor cell is employed to mimic metastatic characteristics in vitro. We identified two proteins, p54nrb and PSF, that can interact with HLJ1 in high cell culture density by immunoprecipitation assay and MALDI-TOF analysis. The complex of HLJ1 and p54nrb was confirmed in vitro and in vivo by co-immunoprecipitation, GST pull-down and mammalian two-hybrid assay. In addition, the results of GST pull-down assay indicated that p54nrb can interact with HLJ1 through HTH motif. We also found that the expressions of both HLJ1 and p54nrb are increased in A549, CL1-0, CL1-5 and CL1-5F4 cancer cell lines while are culturing in high cell density. The results of immunofluorescent staining and cytosolic/nuclear protein fraction revealed that p54nrb is mainly located in the nucleus. Furthermore, we found that over-expression of p54nrb protein in the highly invasive lung cancer cell line, CL1-5, can reduce cancer cell proliferation, colony formation, invasion and migration. On the other hand, p54nrb was decreased when most cells are in DNA synthesis phase. Once over-expression of p54nrb in CL1-5 cell line, the cell cycle would arrest in G1 phase to reduce cancer cell proliferation. Investigating the action mechanism of HLJ1-p54nrb interaction is important, it may not only provide a new insight to understand the pathway of metastasis and growth regulation but also be as the new target molecule for anti-cancer therapy in the future. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2188. doi:10.1158/1538-7445.AM2011-2188

Abstract 2360: Dimethyl sulfoxide induces upregulation of tumor suppressor HLJ1 through activator protein-1 activation in human lung adenocarcinoma CL1-5 cells

Dimethyl sulfoxide (DMSO) is an amphipathic molecule and has a diversity of antitumor activities. Previous studies demonstrated that DMSO could modulate AP-1 activity and lead to cell cycle arrest at G1 phase. HLJ1 is a newly identified tumor and invasion suppressor that inhibits tumorigenesis and cancer metastasis. Its transcriptional activity is also regulated by transcription factor AP-1. However, the effect of DMSO on HLJ1 is still unknown. In this study, low-HLJ1 expressing highly invasive CL1-5 lung adenocarcinoma cells were subjected to DMSO treatment. We found that DMSO can significantly inhibit cancer cell invasion and migration capabilities through up-regulation of HLJ1 in a concentration-dependent manner. In addition, knockdown of HLJ1 expression by siRNA was able to block the effects of DMSO-induction. The HLJ1 promoter and enhancer reporter assay revealed that DMSO transcriptionally upregulates HLJ1 expression through an AP-1 site within the HLJ1 enhancer. Furthermore, AP-1 subfamily members, JunD and JunB, were significantly upregulated by DMSO in a concentration-dependent manner. In conclusion, our results suggest that DMSO could be an important stimulator of the tumor suppressor protein, HLJ1, through AP-1 activation in highly invasive lung adenocarcinoma CL1-5 cells. Our findings provide some important information for further investigations to develop new drugs such as DMSO-derived analogues which may inhibit cancer invasion and progression by targeting HLJ1. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2360. doi:10.1158/1538-7445.AM2011-2360