Smac/DIABLO regulates the apoptosis of hypertrophic scar fibroblasts

Liu,Bao-Heng; Chen,Liang; Li,Shi-Rong; Wang,Zhen-Xiang; Cheng,Wen-Guang

doi:10.3892/ijmm.2013.1442

Smac/DIABLO regulates the apoptosis of hypertrophic scar fibroblasts

Authors:
- Bao-Heng Liu
- Liang Chen
- Shi-Rong Li
- Zhen-Xiang Wang
- Wen-Guang Cheng
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Affiliations: Department of Plastic and Reconstructive Surgery, Southwest Hospital, The Third Military Medical University, Chongqing 400038, P.R. China
Published online on: July 15, 2013 https://doi.org/10.3892/ijmm.2013.1442
Pages: 615-622

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Abstract

In abnormal skin wound healing, hypertrophic scars (HS) are characterized by excessive fibroblast hypercellularity and an overproduction of collagen, leading to atypical extracellular matrix (ECM) remodeling. Although the exact mechanisms of HS remain unclear, decreased HS fibroblast (HSFB) apoptosis and increased proliferation are evident in the development of HS. In this study, the contribution of the second mitochondria-derived activator of caspases/direct inhibitor of apoptosis protein (IAP)-binding protein with a low isoelectric point (pI) (Smac/DIABLO), an apoptosis-promoting protein released from the mitochondria, was investigated in human normal skin and HSFB cultures. The expression of Smac/DIABLO is usually decreased in many malignant tumors compared with normal tissues. Immunohistochemical analysis of skin tissues and the western blot analyses of fibroblasts revealed that the expression of Smac/DIABLO was lower in HS tissues compared with normal skin tissues. Of note, adenovirus-mediated Smac/DIABLO overexpression in the cultured HSFBs significantly reduced cell proliferation, as detected by the cell counting kit-8, and increased caspase-3 and -9 activity, as detected by spectrofluorimetry. In addition, it increased apoptosis, as detected by fluorescence-activated cell sorting (FACS). Furthermore, we found that the silencing of Smac with siRNA in the HSFBs induced a noticeable decrease in caspase-3 and -9 activity, leading to a significant reduction in apoptosis. In addition, the mRNA expression of type I and III pro-collagen detected in the HSFBs was significantly increased following the silencing of Smac with siRNA and was inhibited following Smac/DIABLO overexpression, as shown by real-time RT-PCR. In conclusion, Smac/DIABLO decreases the proliferation and increases the apoptosis of HSFBs. To our knowledge, the data from our study suggest for the first time that Smac/DIABLO is a novel therapeutic target for HS.

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1	O’Leary R, Wood EJ and Guillou PJ: Pathological scarring: strategic interventions. Eur J Surg. 168:523–534. 2002.
2	van der Veer WM, Bloemen MC, Ulrich MM, et al: Potential cellular and molecular causes of hypertrophic scar formation. Burns. 35:15–29. 2009.PubMed/NCBI
3	De Felice B, Garbi C, Santoriello M, et al: Differential apoptosis markers in human keloids and hypertrophic scars fibroblasts. Mol Cell Biochem. 327:191–201. 2009.PubMed/NCBI
4	Greenhalgh DG: The role of apoptosis in wound healing. Int J Biochem Cell Biol. 30:1019–1030. 1998. View Article : Google Scholar : PubMed/NCBI
5	Desmouliere A, Badid C, Bochaton-Piallat ML and Gabbiani G: Apoptosis during wound healing, fibrocontractive diseases and vascular wall injury. Int J Biochem Cell Biol. 29:19–30. 1997. View Article : Google Scholar : PubMed/NCBI
6	Linge C, Richardson J, Vigor C, et al: Hypertrophic scar cells fail to undergo a form of apoptosis specific to contractile collagen-the role of tissue transglutaminase. J Invest Dermatol. 125:72–82. 2005. View Article : Google Scholar : PubMed/NCBI
7	Akasaka Y, Fujita K, Ishikawa Y, et al: Detection of apoptosis in keloids and a comparative study on apoptosis between keloids, hypertrophic scars, normal healed flat scars, and dermatofibroma. Wound Repair Regen. 9:501–506. 2001. View Article : Google Scholar : PubMed/NCBI
8	Tanaka A, Hatoko M, Tada H, et al: Expression of p53 family in scars. J Dermatol Sci. 34:17–24. 2004. View Article : Google Scholar : PubMed/NCBI
9	Aarabi S, Bhatt KA, Shi Y, et al: Mechanical load initiates hypertrophic scar formation through decreased cellular apoptosis. FASEB J. 21:3250–3261. 2007. View Article : Google Scholar : PubMed/NCBI
10	Du C, Fang M, Yucheng Li, et al: Smac, a mitochondrial protein that promotes cytochrome c-dependent caspase activation by eliminating IAP inhibition. Cell. 102:33–42. 2000. View Article : Google Scholar : PubMed/NCBI
11	Verhagen AM, Ekert PG, Pakusch M, et al: Identification of DIABLO, a mammalian protein that promotes apoptosis by binding to and antagonizing IAP proteins. Cell. 102:43–53. 2000. View Article : Google Scholar : PubMed/NCBI
12	Mao HL, Liu PS, Zheng JF, et al: Transfection of Smac/DIABLO sensitizes drug-resistant tumor cells to TRAIL or paclitaxel-induced apoptosis in vitro. Pharmacol Res. 56:483–492. 2007. View Article : Google Scholar : PubMed/NCBI
13	Kempkensteffen C, Hinz S, Christoph F, et al: Expression levels of the mitochondrial IAP antagonists Smac/DIABLO and Omi/HtrA2 in clear-cell renal cell carcinomas and their prognostic value. J Cancer Res Clin Oncol. 134:543–550. 2008. View Article : Google Scholar : PubMed/NCBI
14	Mizutani Y, Nakanishi H, Yamamoto K, et al: Downregulation of Smac/DIABLO expression in renal cell carcinoma and its prognostic significance. J Clin Oncol. 23:448–454. 2005. View Article : Google Scholar : PubMed/NCBI
15	Sekimura A, Konishi A, Mizuno K, et al: Expression of Smac/DIABLO is a novel prognostic marker in lung cancer. Oncol Rep. 11:797–802. 2004.PubMed/NCBI
16	Kempkensteffen C, Jager T, Bub J, et al: The equilibrium of XIAP and Smac/DIABLO expression is gradually deranged during the development and progression of testicular germ cell tumours. Int J Androl. 30:476–483. 2007. View Article : Google Scholar : PubMed/NCBI
17	Bao ST, Gui SQ and Lin MS: Relationship between expression of Smac and Survivin and apoptosis of primary hepatocellular carcinoma. Hepatobiliary Pancreat Dis Int. 5:580–583. 2006.PubMed/NCBI
18	Martinez-Ruiz G, Maldonado V, Ceballos-Cancino G, et al: Role of Smac/DIABLO in cancer progression. J Exp Clin Cancer Res. 27:482008. View Article : Google Scholar : PubMed/NCBI
19	Sun Z, Li s, Cao C, et al: shRNA targeting SFRP2 promotes the apoptosis of hypertrophic scar fibroblast. Mol Cell Biochem. 352:25–33. 2011. View Article : Google Scholar : PubMed/NCBI
20	Guo L, Chen L, Bi S, et al: PTEN inhibits proliferation and functions of hypertrophic scar fibroblasts. Mol Cell Biochem. 361:161–168. 2012. View Article : Google Scholar : PubMed/NCBI
21	Cao C, Li S, Dai X, et al: Genistein inhibits proliferation and functions of hypertrophic scar fibroblasts. Burns. 35:89–97. 2009. View Article : Google Scholar : PubMed/NCBI
22	Mahdavian Delavary B, van der Veer WM, van Egmond M, et al: Macrophages in skin injury and repair. Immunobiology. 216:753–762. 2011.PubMed/NCBI
23	Honardoust D, Ding J, Varkey M, et al: Deep dermal fibroblasts refractory to migration and decorin-induced apoptosis contribute to hypertrophic scarring. J Burn Care Res. 33:668–677. 2012. View Article : Google Scholar : PubMed/NCBI
24	Akasaka Y, Ono I, Kamiya T, et al: The mechanisms underlying fibroblast apoptosis regulated by growth factors during wound healing. J Pathol. 221:285–299. 2010. View Article : Google Scholar : PubMed/NCBI
25	Jiang L, Zhang E, Yang Y, et al: Effectiveness of apoptotic factors expressed on the wounds of patients with stage III pressure ulcers. J Wound Ostomy Continence Nurs. 39:391–396. 2012. View Article : Google Scholar : PubMed/NCBI
26	Jia L, Patwari Y, Kelsey SM, et al: Role of Smac in human leukaemic cell apoptosis and proliferation. Oncogene. 22:1589–1599. 2003. View Article : Google Scholar : PubMed/NCBI
27	Chen DJ and Huerta S: Smac mimetics as new cancer therapeutics. Anticancer Drugs. 20:646–658. 2009. View Article : Google Scholar : PubMed/NCBI
28	Chai J, Du C, Wu JW, et al: Structural and biochemical basis of apoptotic activation by Smac/DIABLO. Nature. 406:855–862. 2000. View Article : Google Scholar : PubMed/NCBI
29	Wu G, Chai J, Suber TL, et al: Structural basis of IAP recognition by Smac/DIABLO. Nature. 408:1008–1012. 2000. View Article : Google Scholar : PubMed/NCBI
30	Gao Z, Tian Y, Wang J, et al: A dimeric Smac/diablo peptide directly relieves caspase-3 inhibition by XIAP. Dynamic and cooperative regulation of XIAP by Smac/Diablo. J Biol Chem. 282:30718–30727. 2007. View Article : Google Scholar : PubMed/NCBI
31	Clark JA, Cheng JC and Leung KS: Mechanical properties of normal skin and hypertrophic scar. Burns. 22:443–446. 1996. View Article : Google Scholar : PubMed/NCBI
32	Oliveira GV, Hawkins HK, Chinkes D, et al: Hypertrophic vs. non hypertrophic scars compared by immunohistochemistry and laser confocal microscopy: type I and III collagens. Int Wound J. 6:445–452. 2009. View Article : Google Scholar : PubMed/NCBI
33	Akita S, Akino K, Tanaka K, et al: A basic fibroblast growth factor improves lower extremity wound healing with a porcine-derived skin substitute. J Trauma. 64:809–815. 2008. View Article : Google Scholar : PubMed/NCBI
34	Cho JW, Kang MC and Lee KS: TGF-β1-treated ADSCs-CM promotes expression of type I collagen and MMP-1, migration of human skin fibroblasts, and wound healing in vitro and in vivo. Int J Mol Med. 26:901–906. 2010.
35	Yan G, Sun H, Wang F, et al: Topical application of hPDGF-A-modified porcine BMSC and keratinocytes loaded on acellular HAM promotes the healing of combined radiation-wound skin injury in minipigs. Int J Radiat Biol. 87:591–600. 2011. View Article : Google Scholar : PubMed/NCBI
36	Weshahy AH and Abdel Hay R: Intralesional cryosurgery and intralesional steroid injection: a good combination therapy for treatment of keloids and hypertrophic scars. Dermatol Ther. 25:273–276. 2012. View Article : Google Scholar : PubMed/NCBI
37	Hayashi T, Furukawa H, Oyama A, et al: A new uniform protocol of combined corticosteroid injections and ointment application reduces recurrence rates after surgical keloid/hypertrophic scar excision. Dermatol Surg. 38:893–897. 2012. View Article : Google Scholar
38	Wu JG, Ma L, Zhang SY, et al: Essential oil from rhizomes of Ligusticum chuanxiong induces apoptosis in hypertrophic scar fibroblasts. Pharm Biol. 49:86–93. 2010.
39	Morin C, Roumegous A, Carpentier G, et al: Modulation of inflammation by Cicaderma ointment accelerates skin wound healing. J Pharmacol Exp Ther. 343:115–124. 2012. View Article : Google Scholar : PubMed/NCBI