Silencing STAT3 with short hairpin RNA enhances radiosensitivity of human laryngeal squamous cell carcinoma xenografts in vivo

Li,Xiaoming; Wang,Hairu; Lu,Xiuying; Di,Bin

doi:10.3892/etm.2010.156

Silencing STAT3 with short hairpin RNA enhances radiosensitivity of human laryngeal squamous cell carcinoma xenografts in vivo

Authors:
- Xiaoming Li
- Hairu Wang
- Xiuying Lu
- Bin Di
View Affiliations

Affiliations: Department of Otolaryngology-Head and Neck Surgery, Bethune International Peace Hospital, Shijiazhuang, Hebei 050082, P.R. China, The Pepole's Hospital of Haikou, Haikou, Hainan 570208, P.R. China
Published online on: September 29, 2010 https://doi.org/10.3892/etm.2010.156
Pages: 947-953

Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )

Metrics: Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )

Cited By (CrossRef): 0 citations Loading Articles...

Abstract

Short hairpin RNA (shRNA) targeting signal transducer and activator of transcription 3 (STAT3) potentiate the radiosensitivity of human laryngeal squamous carcinoma cells in vitro. In the present study, we investigated the inhibitory effect of STAT3 shRNA plus radiotherapy on nude mouse laryngeal squamous cell carcinoma xenografts. The xenotransplanted tumors were treated with STAT3 shRNA, with or without radiation, following a planned scheme. The inhibition rate for tumor growth was calculated and the tumor growth curve was plotted. In addition, the expression of p-STAT3, B cell lymphoma 2 (Bcl-2), p53, vascular endothelial growth factor (VEGF) protein and intratumoral microvessel density (MVD) was determined by immunohistochemistry. Flow cytometry was used to detect the rate of cell apoptosis. The results revealed that STAT3 shRNA transfection plus radiotherapy significantly minimized tumor volume and increased the rate of tumor inhibition. p-STAT3 protein expression and intratumoral MVD were observed to be down-regulated, whereas apoptosis was increased. There was a positive correlation between the expression of p-STAT3 and Bcl-2, and also between the expression of p53 and VEGF, and MVD. These findings indicate that STAT3 shRNA potentiate the radiosensitivity of laryngeal carcinoma xenografts in vivo by regulating downstream signaling proteins in the STAT3 pathway.

View Figures

View References

1.	Rhee JG, Li D, O’Malley BW Jr and Suntharalingam M: Combination radiation and adenovirus-mediated P16(INK4A) gene therapy in a murine model for head and neck cancer. ORL J Otorhinolaryngol Relat Spec. 65:144–154. 2003. View Article : Google Scholar : PubMed/NCBI
2.	Rhee JG, Li D, Suntharalingam M, Guo C, O’Malley BW Jr and Carney JP: Radiosensitization of head/neck squamous cell carcinoma by adenovirus-mediated expression of the Nbs1 protein. Int J Radiat Oncol Biol Phys. 67:273–278. 2007. View Article : Google Scholar : PubMed/NCBI
3.	Takeda K, Noguchi K, Shi W, et al: Targeted disruption of the mouse Stat3 gene leads to early embryonic lethality. Proc Natl Acad Sci USA. 94:3801–3804. 1997. View Article : Google Scholar : PubMed/NCBI
4.	Fukada T, Ohtani T, Yoshida Y, et al: STAT3 orchestrates contradictory signals in cytokine-induced G1 to S cell-cycle transition. EMBO J. 17:6670–6677. 1998. View Article : Google Scholar : PubMed/NCBI
5.	Catlett-Falcone R, Landowski TH, Oshiro MM, et al: Constitutive activation of Stat3 signaling confers resistance to apoptosis in human U266 myeloma cells. Immunity. 10:105–115. 1999. View Article : Google Scholar : PubMed/NCBI
6.	Bromberg JF: Activation of STAT proteins and growth control. Bioessays. 23:161–169. 2001. View Article : Google Scholar : PubMed/NCBI
7.	Niu G, Wright KL, Ma Y, et al: Role of Stat3 in regulating p53 expression and function. Mol Cell Biol. 25:7432–7440. 2005. View Article : Google Scholar : PubMed/NCBI
8.	Odajima J, Matsumura I, Sonoyama J, et al: Full oncogenic activities of v-Src are mediated by multiple signaling pathways. Ras as an essential mediator for cell survival. J Biol Chem. 275:24096–24105. 2000.PubMed/NCBI
9.	Ning ZQ, Li J, McGuinness M and Arceci RJ: STAT3 activation is required for Asp(816) mutant c-Kit induced tumorigenicity. Oncogene. 20:4528–4536. 2001. View Article : Google Scholar
10.	Bowman T, Broome MA, Sinibaldi D, et al: Stat3-mediated Myc expression is required for Src transformation and PDGF-induced mitogenesis. Proc Natl Acad Sci USA. 98:7319–7324. 2001. View Article : Google Scholar : PubMed/NCBI
11.	Sinibaldi D, Wharton W, Turkson J, Bowman T, Pledger WJ and Jove R: Induction of p21WAF1/CIP1 and cyclin D1 expression by the Src oncoprotein in mouse fibroblasts: role of activated STAT3 signaling. Oncogene. 19:5419–5427. 2000. View Article : Google Scholar : PubMed/NCBI
12.	Karni R, Jove R and Levitzki A: Inhibition of pp60c-Src reduces Bcl-XL expression and reverses the transformed phenotype of cells overexpressing EGF and HER-2 receptors. Oncogene. 18:4654–4662. 1999. View Article : Google Scholar : PubMed/NCBI
13.	Aoki Y, Feldman GM and Tosato G: Inhibition of STAT3 signaling induces apoptosis and decreases survivin expression in primary effusion lymphoma. Blood. 101:1535–1542. 2003. View Article : Google Scholar : PubMed/NCBI
14.	Gritsko T, Williams A, Turkson J, et al: Persistent activation of stat3 signaling induces survivin gene expression and confers resistance to apoptosis in human breast cancer cells. Clin Cancer Res. 12:11–19. 2006. View Article : Google Scholar : PubMed/NCBI
15.	Epling-Burnette PK, Liu JH, Catlett-Falcone R, et al: Inhibition of STAT3 signaling leads to apoptosis of leukemic large granular lymphocytes and decreased Mcl-1 expression. J Clin Invest. 107:351–362. 2001. View Article : Google Scholar : PubMed/NCBI
16.	Wei D, Le X, Zheng L, et al: Stat3 activation regulates the expression of vascular endothelial growth factor and human pancreatic cancer angiogenesis and metastasis. Oncogene. 22:319–329. 2003. View Article : Google Scholar : PubMed/NCBI
17.	Li X, Wang H, Lu X and Di B: STAT3 blockade with shRNA enhances radiosensitivity in Hep-2 human laryngeal squamous carcinoma cells. Oncol Rep. 23:345–353. 2010.PubMed/NCBI
18.	Bissery MC, Guenard D, Gueritte-Voegelein F and Lavelle F: Experimental antitumor activity of taxotere (RP 56976, NSC 628503), a taxol analogue. Cancer Res. 51:4845–4852. 1991.PubMed/NCBI
19.	Crisby M, Nordin-Fredriksson G, Shah PK, Yano J, Zhu J and Nilsson J: Pravastatin treatment increases collagen content and decreases lipid content, inflammation, metalloproteinases, and cell death in human carotid plaques: implications for plaque stabilization. Circulation. 103:926–933. 2001. View Article : Google Scholar
20.	Weidner N, Semple JP, Welch WR and Folkman J: Tumor angio-genesis and metastasis – correlation in invasive breast carcinoma. N Engl J Med. 324:1–8. 1991.
21.	Turkson J and Jove R: STAT proteins: novel molecular targets for cancer drug discovery. Oncogene. 19:6613–6626. 2000. View Article : Google Scholar : PubMed/NCBI
22.	Bharti AC, Shishodia S, Reuben JM, et al: Nuclear factor-kappaB and STAT3 are constitutively active in CD138+ cells derived from multiple myeloma patients, and suppression of these transcription factors leads to apoptosis. Blood. 103:3175–3184. 2004.
23.	Greten FR, Weber CK, Greten TF, et al: Stat3 and NF-kappaB activation prevents apoptosis in pancreatic carcinogenesis. Gastroenterology. 123:2052–2063. 2002. View Article : Google Scholar : PubMed/NCBI
24.	Real PJ, Sierra A, De Juan A, Segovia JC, Lopez-Vega JM and Fernandez-Luna JL: Resistance to chemotherapy via Stat3-dependent overexpression of Bcl-2 in metastatic breast cancer cells. Oncogene. 21:7611–7618. 2002. View Article : Google Scholar : PubMed/NCBI
25.	Otero DC, Poli V, David M and Rickert RC: Cutting edge: inherent and acquired resistance to radiation-induced apoptosis in B cells: a pivotal role for STAT3. J Immunol. 177:6593–6597. 2006. View Article : Google Scholar
26.	Calvin DP, Nam S, Buettner R, Sekharam M, Torres-Roca J and Jove R: Inhibition of STAT3 activity with STAT3 antisense oligonucleotide (STAT3-ASO) enhances radiation induced apoptosis in DU145 prostate cancer cells. Int J Radiat Oncol Biol Phys. 57:S2972003. View Article : Google Scholar
27.	Zhang YC, Taylor MM, Samson WK and Phillips MI: Antisense inhibition: oligonucleotides, ribozymes, and siRNAs. Methods Mol Med. 106:11–34. 2005.PubMed/NCBI
28.	Amin HM, McDonnell TJ, Ma Y, et al: Selective inhibition of STAT3 induces apoptosis and G(1) cell cycle arrest in ALK-positive anaplastic large cell lymphoma. Oncogene. 23:5426–5434. 2004. View Article : Google Scholar : PubMed/NCBI
29.	Niu G, Wright KL, Huang M, et al: Constitutive Stat3 activity up-regulates VEGF expression and tumor angiogenesis. Oncogene. 21:2000–2008. 2002. View Article : Google Scholar : PubMed/NCBI