title: Small interfering RNA targeting epidermal growth factor receptor enhances chemosensitivity to cisplatin, 5-fluorouracil and docetaxel in head and neck squamous cell carcinoma.
abstract: Overexpression of epidermal growth factor receptor (EGFR) has been found in various epithelial malignancies, including head and neck squamous cell carcinoma (HNSCC), and is associated with increased tumor growth, metastasis, resistance to chemotherapeutic agents and poor prognosis. As such, EGFR is a potential target for antitumor therapy and several EGFR inhibitors have been investigated in preclinical or clinical settings. In the present study, we used small interfering RNA (siRNA) to downregulate EGFR expression while evaluating the effect of EGFR siRNA on cell proliferation, and the combined effects with cisplatin, 5-fluorouracil (5-FU) and docetaxel in HNSCC. Furthermore, HNSCC xenografts were treated with EGFR siRNA alone or in combination with cisplatin, and tumor growth was examined. EGFR expression, proliferation, angiogenesis and apoptosis index were evaluated by immunohistochemistry. The results showed that EGFR siRNA efficiently downregulated EGFR expression and inhibited cell growth of HNSCC. Treatment with EGFR siRNA in combination with cisplatin, 5-FU and docetaxel enhanced chemosensitivity with a significant increase in apoptosis. EGFR siRNA delivered by atelocollagen enhanced the antitumor effect of cisplatin in the HNSCC xenograft model. These cumulative results suggest that EGFR siRNA combined with cisplatin, 5-FU and docetaxel may be a feasible strategy to enhance the effects of chemotherapy in patients with HNSCC.
authors.affiliation: Department of Oral and Maxillofacial Surgery, National Defense Medical College, Namiki, Tokorozawa, Saitama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nozawa
authors.forename: Takushi
authors.initials: T
authors.lastname: Tadakuma
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ono
authors.forename: Masaki
authors.initials: M
authors.lastname: Sato
authors.forename: Sadayuki
authors.initials: S
authors.lastname: Hiroi
authors.forename: Kazuma
authors.initials: K
authors.lastname: Masumoto
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Sato
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols; D001483:Base Sequence; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000628:therapy; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000627:therapeutic use; D003131:Combined Modality Therapy; D000077143:Docetaxel; D019008:Drug Resistance, Neoplasm / Q000187:drug effects* / Q000235:genetics; D066246:ErbB Receptors / Q000037:antagonists & inhibitors* / Q000235:genetics; D005472:Fluorouracil / Q000627:therapeutic use; D006258:Head and Neck Neoplasms / Q000188:drug therapy* / Q000628:therapy; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D008969:Molecular Sequence Data; D034741:RNA, Small Interfering / Q000235:genetics / Q000627:therapeutic use*; D043823:Taxoids / Q000627:therapeutic use; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; D034741:RNA, Small Interfering; D043823:Taxoids; D000077143:Docetaxel; D066246:ErbB Receptors; D002945:Cisplatin; D005472:Fluorouracil