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Garcia-Mouronte E, Berna-Rico E, de Nicolas-Ruanes B, Azcarraga-Llobet C, Alonso-Martinez de Salinas L, Bea-Ardebol S. Imiquimod as Local Immunotherapy in the Management of Premalignant Cutaneous Conditions and Skin Cancer. Int J Mol Sci 2023; 24:10835. [PMID: 37446011 DOI: 10.3390/ijms241310835] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/24/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
Cutaneous cancers are, by far, the most common malignant neoplasms of the human being. Due to the great array of clinical conditions, their worldwide increasing incidence and the steady ageing of the population, non-invasive treatments modalities that show a good clinical response, a proper benefit-risk ratio and cosmetic results are becoming increasingly important in the clinical setting. Imiquimod is a topically applied immunomodulator which is often used in the management of several premalignant and malignant cutaneous disorders. This article is a review of the current literature on its mechanism of action, pharmacokinetics, and therapeutical effects.
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Affiliation(s)
| | - Emilio Berna-Rico
- Dermatology Department, Hospital Universitario Ramon y Cajal, 28034 Madrid, Spain
| | | | | | | | - Sonia Bea-Ardebol
- Dermatology Department, Hospital Universitario Ramon y Cajal, 28034 Madrid, Spain
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Zheng H, Zou Z, Wu X, Xu Y, Zhu J, Zhou Q, Han R, Song Y, Cheng H. HPV11E7 inhibits IMQ-induced chemokine and colony-stimulating factor production in keratinocytes. Gene 2020; 760:145003. [PMID: 32739587 DOI: 10.1016/j.gene.2020.145003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/05/2020] [Accepted: 07/25/2020] [Indexed: 10/23/2022]
Abstract
Imiquimod (IMQ) is approved as a first-line treatment for genital warts caused by human papillomavirus (HPV) infection. However, the recurrence rate is very high. HPV E7 protein plays a critical role in HPV immune escape. However, the role of HPV11 E7 protein in genital warts recurrence during IMQ treatment is not clear. Here, we found that the expression profile of NHEK cells was obviously changed after IMQ treatment, and a large number of genes encoding cytokines and genes involved in cytokine-mediated signaling pathways and cellular metabolic signaling pathways were up- or downregulated. HPV11E7 overexpression inhibited the IMQ-induced production of of multiple chemokines and colony-stimulating factors in NHEK cells. Furthermore, we found that HPV11E7 could impair the activation of mitogen-activated protein kinase (MAPK) signaling pathway. Therefore, our results suggested that HPV11 E7 diminishes the production of chemokines, colony-stimulating factors and other cytokines via inhibition of the MAPK signaling pathway, which suppresses the therapeutic effect of IMQ and promotes the recurrence of diseases, such as condyloma acuminatum.
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Affiliation(s)
- Huimin Zheng
- Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, PR China; Department of Dermatology, Lin Hai First People's Hospital, Taizhou 317000, Zhejiang, PR China
| | - Ziqi Zou
- Institute of Immunology, Zhejiang University School of Medicine, Hangzhou 310058, PR China
| | - Xia Wu
- Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, PR China
| | - Yaohan Xu
- Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, PR China
| | - Jiang Zhu
- Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, PR China
| | - Qiang Zhou
- Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, PR China
| | - Rui Han
- Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, PR China
| | - Yinjing Song
- Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, PR China.
| | - Hao Cheng
- Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, PR China.
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Chuang KC, Chang CR, Chang SH, Huang SW, Chuang SM, Li ZY, Wang ST, Kao JK, Chen YJ, Shieh JJ. Imiquimod-induced ROS production disrupts the balance of mitochondrial dynamics and increases mitophagy in skin cancer cells. J Dermatol Sci 2020; 98:152-162. [PMID: 32376151 DOI: 10.1016/j.jdermsci.2020.03.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 03/10/2020] [Accepted: 03/31/2020] [Indexed: 01/22/2023]
Abstract
BACKGROUND Mitochondrial homeostasis is a highly dynamic process involving continuous fission and fusion cycles and mitophagy to maintain mitochondrial functionality. Imiquimod (IMQ), a Toll-like receptor (TLR) 7 ligand, is used to treat various skin malignancies. IMQ also induces apoptotic and autophagic cell death in various cancers through a TLR7-independent pathway. OBJECTIVE To investigate whether IMQ-induced ROS production is involved in mitochondrial dysfunction, mitochondrial fragmentation and mitophagy in skin cancer cells. METHODS BCC/KMC-1, B16F10 and A375 skin cancer cells, AGS gastric cancer cells and primary human keratinocytes were treated with 50 μg/mL IMQ. After 4 h, ROS were detected by CM-H2DCFDA, DHE, and MitoSOX Red staining. After 24 h, cell viability and the mitochondrial membrane potential were evaluated by a CCK-8 assay and JC-1 staining, respectively. Oxygen consumption was assessed with an Oroboros instrument. Mitochondrial morphology and mitophagy were evaluated by MitoTracker and LysoTracker staining. Mitochondrial dynamics markers, including MFN-1, DRP-1 and OPA1, and mitophagy markers, including LC3, S65-phosphorylated ubiquitin, PINK1 and TOM20, were detected by immunoblotting. RESULTS IMQ not only induced severe ROS production but also resulted in increased mitochondrial membrane potential loss, mitochondrial fission and mitophagy and decreased oxygen consumption in skin cancer cells compared with normal keratinocytes. Pretreatment with the antioxidant NAC reduced IMQ-induced ROS production and attenuated IMQ-induced mitochondrial fission and mitophagy in skin cancer cells. CONCLUSIONS IMQ-induced ROS might be associated with mitochondrial dysfunction, mitochondrial fission and mitophagy in cancer cells. Alleviating IMQ-induced ROS production would reduce mitochondrial fission-to-fusion skewing and further reduce IMQ-induced mitophagy.
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Affiliation(s)
- Kai-Cheng Chuang
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Chuang-Rung Chang
- Institute of Biotechnology, National Tsing Hua University, Hsin Chu, Taiwan
| | - Shu-Hao Chang
- Institute of Clinical Medicine, National Yang Ming University, Taipei, Taiwan
| | - Shi-Wei Huang
- Center for Cell Therapy and Translation Research, China Medical University Hospital, Taichung, Taiwan
| | - Show-Mei Chuang
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Zheng-Yi Li
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Sin-Ting Wang
- Division of Translational Research and Center of Excellence for Cancer Research, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Jun-Kai Kao
- Department of Pediatrics, Children's Hospital, Changhua Christian Hospital, Changhua, Taiwan; School of Medicine, Kaohsiung Medical University, Kaohsiung City, Taiwan
| | - Yi-Ju Chen
- Department of Dermatology, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Jeng-Jer Shieh
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan; Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan; Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, Taiwan.
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Imiquimod-induced autophagy is regulated by ER stress-mediated PKR activation in cancer cells. J Dermatol Sci 2017; 87:138-148. [DOI: 10.1016/j.jdermsci.2017.04.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 03/30/2017] [Accepted: 04/25/2017] [Indexed: 12/17/2022]
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The Immunomodulatory Small Molecule Imiquimod Induces Apoptosis in Devil Facial Tumour Cell Lines. PLoS One 2016; 11:e0168068. [PMID: 27936237 PMCID: PMC5148113 DOI: 10.1371/journal.pone.0168068] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 11/28/2016] [Indexed: 12/13/2022] Open
Abstract
The survival of the Tasmanian devil (Sarcophilus harrisii) is threatened by devil facial tumour disease (DFTD). This transmissible cancer is usually fatal, and no successful treatments have been developed. In human studies, the small immunomodulatory molecule imiquimod is a successful immunotherapy, activating anti-tumour immunity via stimulation of toll-like receptor-7 (TLR7) signaling pathways. In addition, imiquimod is a potent inducer of apoptosis in human tumour cell lines via TLR7 independent mechanisms. Here we investigate the potential of imiquimod as a DFTD therapy through analysis of treated DFTD cell lines and Tasmanian devil fibroblasts. WST-8 proliferation assays and annexin V apoptosis assays were performed to monitor apoptosis, and changes to the expression of pro- and anti-apoptotic genes were analysed using qRT-PCR. Our results show that DFTD cell lines, but not Tasmanian devil fibroblasts, are sensitive to imiquimod-induced apoptosis in a time and concentration dependent manner. Induction of apoptosis was accompanied by down-regulation of the anti-apoptotic BCL2 and BCLXL genes, and up-regulation of the pro-apoptotic BIM gene. Continuous imiquimod treatment was required for these effects to occur. These results demonstrate that imiquimod can deregulate DFTD cell growth and survival in direct and targeted manner. In vivo, this may increase DFTD vulnerability to imiquimod-induced TLR7-mediated immune responses. Our findings have improved the current knowledge of imiquimod action in tumour cells for application to both DFTD and human cancer therapy.
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Almomen A, Jarboe EA, Dodson MK, Peterson CM, Owen SC, Janát-Amsbury MM. Imiquimod Induces Apoptosis in Human Endometrial Cancer Cells In vitro and Prevents Tumor Progression In vivo. Pharm Res 2016; 33:2209-17. [PMID: 27245465 PMCID: PMC4967407 DOI: 10.1007/s11095-016-1957-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/25/2016] [Indexed: 01/10/2023]
Abstract
PURPOSE The increasing incidence of endometrial cancer (EC), in younger age at diagnosis, calls for new tissue-sparing treatment options. This work aims to evaluate the potential of imiquimod (IQ) in the treatment of low-grade EC. METHODS Effects of IQ on the viabilities of Ishikawa and HEC-1A cells were evaluated using MTT assay. The ability of IQ to induce apoptosis was evaluated by testing changes in caspase 3/7 levels and expression of cleaved caspase-3, using luminescence assay and western blot. Apoptosis was confirmed by flow cytometry and the expression of cleaved PARP. Western blot was used to evaluate the effect of IQ on expression levels of Bcl-2, Bcl-xL, and BAX. Finally, the in vivo efficacy of IQ was tested in an EC mouse model. RESULTS There was a decrease in EC cell viability following IQ treatment as well as increased caspase 3/7 activities, cleaved caspase-3 expression, and Annexin-V/ 7AAD positive cell population. Western blot results showed the ability of IQ in cleaving PARP, decreasing Bcl-2 and Bcl-xL expressions, but not affecting BAX expression. In vivo study demonstrated IQ's ability to inhibit EC tumor growth and progression without significant toxicity. CONCLUSIONS IQ induces apoptosis in low-grade EC cells in vitro, probably through its direct effect on Bcl-2 family protein expression. In, vivo, IQ attenuates EC tumor growth and progression, without an obvious toxicity. Our study provides the first building block for the potential role of IQ in the non-surgical management of low-grades EC and encouraging further investigations.
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Affiliation(s)
- Aliyah Almomen
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, University of Utah, Salt Lake City, UT, 84132, USA
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT, 84112, USA
| | - Elke A Jarboe
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, University of Utah, Salt Lake City, UT, 84132, USA
- Department of Pathology, University of Utah, Salt Lake City, UT, 84112, USA
| | - Mark K Dodson
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, University of Utah, Salt Lake City, UT, 84132, USA
| | - C Matthew Peterson
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, University of Utah, Salt Lake City, UT, 84132, USA
| | - Shawn C Owen
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT, 84112, USA
| | - Margit M Janát-Amsbury
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, University of Utah, Salt Lake City, UT, 84132, USA.
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT, 84112, USA.
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Huang SW, Chang SH, Mu SW, Jiang HY, Wang ST, Kao JK, Huang JL, Wu CY, Chen YJ, Shieh JJ. Imiquimod activates p53-dependent apoptosis in a human basal cell carcinoma cell line. J Dermatol Sci 2016; 81:182-91. [DOI: 10.1016/j.jdermsci.2015.12.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 12/09/2015] [Accepted: 12/28/2015] [Indexed: 12/11/2022]
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Piaserico S, Michelotto A, Frigo AC, Alaibac M. TLR7 Gln11Leu single nucleotide polymorphism and response to treatment with imiquimod in patients with basal cell carcinoma: a pilot study. Pharmacogenomics 2015; 16:1913-7. [DOI: 10.2217/pgs.15.132] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Aim: The Toll-like receptor 7 (TLR7) agonist, imiquimod, offers a topical and noninvasive therapeutic method for the clinical treatment of superficial basal cell carcinoma (BCC). In this study we explored the relationship between the functional X-linked TLR7 rs179008/Gln11Leu polymorphism and the response to imiquimod in patients with BCC. Patients & methods: Thirty-four BCC patients treated with imiquimod were included in the study. SNP genotyping of the TLR7 promoter polymorphism was performed by TaqMan allelic discrimination assay. Results: In the group of female nonresponders to imiquimod a higher frequency of the altered genotype compared with responders was observed. Similarly, in the group of male nonresponders to imiquimod both patients with the mutated genotype were nonresponders. Conclusion: The results of this study show that patients carrying at least one T allele of the TLR7 promoter polymorphism are associated with an increased probability to be resistant to imiquimod therapy.
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Affiliation(s)
- Stefano Piaserico
- Unit of Dermatology, University of Padua, Via Battisti 206, 35100 Padua, Italy
| | - Anna Michelotto
- Unit of Dermatology, University of Padua, Via Battisti 206, 35100 Padua, Italy
| | - Anna C Frigo
- Laboratory of Public Health, University of Padua, Via Loredan 18, 35100 Padua, Italy
| | - Mauro Alaibac
- Unit of Dermatology, University of Padua, Via Battisti 206, 35100 Padua, Italy
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Wang ST, Huang SW, Kao JK, Liang SM, Chen YJ, Chen YY, Wu CY, Shieh JJ. Imiquimod-induced AMPK activation causes translation attenuation and apoptosis but not autophagy. J Dermatol Sci 2015; 78:108-16. [PMID: 25766763 DOI: 10.1016/j.jdermsci.2015.02.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 02/11/2015] [Accepted: 02/17/2015] [Indexed: 12/25/2022]
Abstract
BACKGROUND AMP-activated protein kinase (AMPK), a principal intracellular energy sensor, plays a crucial role in cell growth, proliferation, apoptosis and autophagy. Imiquimod (IMQ) directly exhibits anti-tumor activity through the induction of apoptosis and autophagic cell death. OBJECTIVE To evaluate the role of AMPK in IMQ-induced apoptosis and autophagy. METHODS The phosphorylation of AMPK and its substrates was detected by immunoblotting. ATP contents were analyzed by an ATP bioluminescence assay. The upstream signaling for AMPK activation was dissected by examination of TLR7/8 expression, over-expression of TLR7/8, the addition of AMPK kinase inhibitors, and the genetic silencing of Myd88 and LKB1. The role of AMPK activation in IMQ-induced autophagy and apoptosis was assessed by inhibiting AMPK, genetically silencing AMPK and over-expressing AMPK dominant-negative mutants. Autophagy and apoptosis were evaluated by a DNA content assay, immunoblotting, EGFP-LC3 puncta detection and acridine orange staining. RESULTS IMQ could activate AMPK and autophagy in cancer cells not expressing TLR7/8. IMQ caused ATP depletion and induced LKB1-mediated AMPK activation. The down-regulation of AMPK activity via pharmacological inhibition and genetic silencing resulted in reduced IMQ-induced apoptosis but did not influence autophagy, and this rescue effect was associated with the retention of translation factor activity and anti-apoptotic Bcl-2 family member Mcl-1 protein expression levels. CONCLUSION IMQ induces AMPK activation independent of TLR7/8 expression, resulting in translation inhibition and subsequent apoptosis through ATP depletion and LKB1 signaling, in skin tumor cells.
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Affiliation(s)
- Sin-Ting Wang
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Shi-Wei Huang
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Jun-Kai Kao
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan; Department of Pediatrics, Children's Hospital, Changhua Christian Hospital, Changhua, Taiwan
| | - Shu-Mei Liang
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
| | - Yi-Ju Chen
- Department of Dermatology, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Yu-Yu Chen
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Chun-Ying Wu
- Division of Gastroenterology and Hepatology, Taichung Veterans General Hospital, Taichung, Taiwan.
| | - Jeng-Jer Shieh
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan; Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan; Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, Taiwan.
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Huang SW, Kao JK, Wu CY, Wang ST, Lee HC, Liang SM, Chen YJ, Shieh JJ. Targeting aerobic glycolysis and HIF-1alpha expression enhance imiquimod-induced apoptosis in cancer cells. Oncotarget 2015; 5:1363-81. [PMID: 24658058 PMCID: PMC4012728 DOI: 10.18632/oncotarget.1734] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Tumor cells rely on aerobic glycolysis to maintain unconstrained cell growth and proliferation. Imiquimod (IMQ), a synthetic Toll-like receptor (TLR) 7/8 ligand, exerts anti-tumor effects directly by inducing cell death in cancer cells and/or indirectly by activating cellular immune responses against tumor cells. However, whether IMQ modulates glucose metabolism pathways remains unclear. In this study, we demonstrated that IMQ can enhance aerobic glycolysis by up-regulating HIF-1α expression at the transcriptional and translational levels via ROS mediated STAT3- and Akt-dependent pathways, independent of TLR7/8 signaling. The genetic silencing of HIF-1α not only repressed IMQ-induced aerobic glycolysis but also sensitized cells to IMQ-induced apoptosis due to faster ATP and Mcl-1 depletion. Moreover, the glucose analog 2-DG and the Hsp90 inhibitor 17-AAG, which destabilizes the HIF-1α protein, synergized with IMQ to induce tumor cell apoptosis in vitro and significantly inhibited tumor growth in vivo. Thus, we hypothesize that the IMQ-induced up-regulation of HIF-1α and aerobic glycolysis is a protective response to the metabolic stress generated by IMQ treatment, and thus, co-treatment with inhibitors of HIF-1α and/or glycolysis may be a useful therapeutic strategy to enhance the anti-tumor effects of IMQ in clinical settings.
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Affiliation(s)
- Shi-Wei Huang
- Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan
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Yu X, Wang Y, Zhao W, Zhou H, Yang W, Guan X. Toll-like receptor 7 promotes the apoptosis of THP-1-derived macrophages through the CHOP-dependent pathway. Int J Mol Med 2014; 34:886-93. [PMID: 24994112 DOI: 10.3892/ijmm.2014.1833] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 06/25/2014] [Indexed: 11/06/2022] Open
Abstract
Macrophage apoptosis is a prominent characteristic of advanced atherosclerotic plaques and leads to plaque destabilization. Certain studies have confirmed that influenza virus A (IVA) infection is related to acute myocardial infarction (AMI). However, it remains unknown as to whether this phenomenon is associated with Toll-like receptor (TLR)7, since single-stranded RNA (ssRNA) of IVA is a natural ligand of TLR7. Thus, in the present study, THP-1‑derived macrophages were infected with IVA or treated with imiquimod (IMQ) in the presence or absence of pre-treatment with oxidized low-density lipoprotein (oxLDL). The macrophages were pre-treated with oxLDL (5 µg/ml) for 24 h to mimic high lipid conditions. Cell viability and apoptosis were detected by 3-(4,5-dimethylthiazol-2-y-1)‑2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and flow cytometry, respectively. Our results revealed that TLR7 played an important role in macrophage apoptosis and cytokine secretion. Both IVA infection and IMQ treatment increased TLR7 expression, as well as the secretion of pro-inflammatory cytokines [interleukin (IL)-6, monocyte chemotactic protein (MCP)-1] and apoptosis. However, this increase in cytokine secretion occurred independently of cell apoptosis. oxLDL had potential synergistic pro-apoptotic effects combined with TLR7 activation. To determine whether endoplasmic reticulum (ER) stress plays a role in cell apoptosis, the mRNA and protein expression of known markers of ER stress [glucose-regulated protein (GRP)78 and C/EBP homologous protein (CHOP)] was detected by reverse transcription PCR (RT-PCR), quantitative reverse transcription PCR (qRT-PCR) and western blot analysis. Our results revealed that apoptosis aggravated ER stress, as shown by the overexpression of the pro-apoptotic sensor, CHOP. In conclusion, our study demonstrates the converging role of oxLDL pre-treatment, IVA infection and IMQ in ER stress-induced cell apoptosis.
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Affiliation(s)
- Xiaochen Yu
- Department of Laboratory Diagnostics, First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Yang Wang
- Department of Laboratory Diagnostics, First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Wenhui Zhao
- Department of Laboratory Diagnostics, First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Haizhou Zhou
- Department of Laboratory Diagnostics, First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Wei Yang
- Department of Laboratory Diagnostics, First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Xiuru Guan
- Department of Laboratory Diagnostics, First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
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Henriques L, Palumbo M, Guay MP, Bahoric B, Basik M, Kavan P, Batist G. Imiquimod in the treatment of breast cancer skin metastasis. J Clin Oncol 2014; 32:e22-5. [PMID: 24419128 DOI: 10.1200/jco.2012.46.4883] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- Lisa Henriques
- Faculté de Medicine de l'Université de Montréal, Montreal, Quebec, Canada
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Nie JS, Zhang HM, Zhao J, Liu HJ, Niu Q. Involvement of mitochondrial pathway in benzo[a]pyrene-induced neuron apoptosis. Hum Exp Toxicol 2013; 33:240-50. [DOI: 10.1177/0960327113493301] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Benzo[a]pyrene (B[a]P), a well-known carcinogen, is widespread in the environment. Although the neurotoxic effect of B[a]P has not drawn much attention, toxic effects of B[a]P on learning and memory have been reported. Since it is well known that neuronal apoptosis plays a major role in impairment of learning and memory triggered by many stimuli, an effort has been made to examine whether the B[a]P-induced neurotoxicity occurs through mitochondria-mediated apoptosis. Cultured newborn rat cerebral neurons were used to clarify the apoptosis induced by B[a]P in the study. After incubating with different doses of B[a]P in presence of S9 for 40 h, the apoptotic rates of B[a]P-treated neurons increased in a dose-dependent manner. Further analysis showed that B[a]P-induced apoptosis was accompanied by loss of mitochondrial membrane potential, release of cytochrome c from mitochondria to the cytosol, downregulation of antiapoptotic protein B-cell lymphoma-2 (Bcl-2) levels with concurrent upregulation in proapoptotic Bcl-2-associated X protein (Bax) levels, and increase in the levels and activities of caspases-9 and -3. However, there was no difference in the activity of caspase-8 between B[a]P-exposed neurons and controls. Collectively, these results showed that B[a]P upregulates Bax and downregulates Bcl-2 expression in cultured cerebral neurons, which leads to mitochondrial release of cytochrome c, caspase-3 activation and neuronal apoptotic death.
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Affiliation(s)
- J-S Nie
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, China
| | - H-M Zhang
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, China
| | - J Zhao
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, China
| | - H-J Liu
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, China
| | - Q Niu
- Department of Occupational Health, School of Public Health, Shanxi Medical University, Taiyuan, China
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Han JH, Park SY, Kim JB, Cho SD, Kim B, Kim BY, Kang MJ, Kim DJ, Park JH, Park JH. TLR7 expression is decreased during tumour progression in transgenic adenocarcinoma of mouse prostate mice and its activation inhibits growth of prostate cancer cells. Am J Reprod Immunol 2013; 70:317-26. [PMID: 23790156 DOI: 10.1111/aji.12146] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 06/04/2013] [Indexed: 02/06/2023] Open
Abstract
PROBLEM Although various Toll-like receptors (TLRs) have been associated with immune response and tumorigenesis in the prostate cells, little is known about the role of TLR7. Accordingly, we examined the expression of TLR7 during tumour progression of TRMAP (transgenic mouse model for prostate cancer) mice and its role on cell growth. METHOD OF STUDY Toll-like receptor7 expression was examined by RT-polymerase chain reaction (PCR), Western blot, and immunohistochemistry. Cell growth was examined by MTT assay. Colony formation was investigated by crystal violet staining. RESULTS Strong expression of TLR7 was detected in the normal prostate epithelia of Wild-type (WT) mice, but not in TLR7-deficient mice. In contrast, TLR7 expression was weak in transgenic adenocarcinoma of mouse prostate (TRAMP)-C2 cells, as compared with murine bone marrow-derived macrophages (BMDMs). Moreover, TLR7 mRNA was markedly expressed in RWPE-1 cells (non-cancerous prostate epithelial cells), but not in PC3 and DU145 (prostate cancer cells). Immunohistochemically, TLR7 expression gradually decreased in TRAMP mice depending on the pathologic grade of the prostate cells. TLR7 agonists increased both the gene and protein expression of TLR7 and promoted production of proinflammatory cytokines/chemokines and IFN-β gene expression in prostate cancer cell lines. Moreover, loxoribine inhibited the growth and colony formation of TRAMP-C2 cells dependent of TLR7. CONCLUSION These findings suggest that TLR7 may participate in tumour suppression in the prostate cells.
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Affiliation(s)
- Ju-Hee Han
- Laboratory Animal Medicine, College of Veterinary Medicine, Seoul University, Seoul, Korea
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Subamolide B Isolated from Medicinal Plant Cinnamomum subavenium Induces Cytotoxicity in Human Cutaneous Squamous Cell Carcinoma Cells through Mitochondrial and CHOP-Dependent Cell Death Pathways. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:630415. [PMID: 23573140 PMCID: PMC3610371 DOI: 10.1155/2013/630415] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 02/05/2013] [Indexed: 11/25/2022]
Abstract
Subamolide B is a butanolide isolated from Cinnamomum subavenium, a medicinal plant traditionally used to treat various ailments including carcinomatous swelling. We herein reported for the first time that subamolide B potently induced cytotoxicity against diverse human skin cancer cell lines while sparing nonmalignant cells. Mechanistic studies on human cutaneous squamous cell carcinoma (SCC) cell line SCC12 highlighted the involvement of apoptosis in subamolide B-induced cytotoxicity, as evidenced by the activation of caspases-8, -9, -4, and -3, the increase in annexin V-positive population, and the partial restoration of cell viability by cotreatment with the pan-caspase inhibitor z-VAD-fmk. Additionally, subamolide B evoked cell death pathways mediated by FasL/Fas, mitochondria, and endoplasmic reticulum (ER) stress, as supported by subamolide B-induced FasL upregulation, BCL-2 suppression/cytosolic release of cytochrome c, and UPR activation/CHOP upregulation, respectively. Noteworthy, ectopic expression of c-FLIPL or dominant-negative mutant of FADD failed to impair subamolide B-induced cytotoxicity, whereas BCL-2 overexpression or CHOP depletion greatly rescued subamolide B-stimulated cells. Collectively, these results underscored the central role of mitochondrial and CHOP-mediated cell death pathways in subamolide B-induced cytotoxicity. Our findings further implicate the potential of subamolide B for cutaneous SCC therapy or as a lead compound for developing novel chemotherapeutic agents.
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