Downregulation of CD9 protein expression is associated with aggressive behavior of oral squamous cell carcinoma

Buim, Marcilei Eliza Cavicchioli; Lourenço, Silvia Vanessa; Carvalho, Kátia Candido; Cardim, Roberta; Pereira, Cláudia; Carvalho, André Lopes; Fregnani, José Humberto; Soares, Fernando Augusto

doi:10.1016/j.oraloncology.2009.11.009

« Previous Next »Oral Oncology
Volume 46, Issue 3 , Pages 166-171, March 2010

Downregulation of CD9 protein expression is associated with aggressive behavior of oral squamous cell carcinoma☆

Marcilei Eliza Cavicchioli Buim
- Department of Anatomical Pathology, Hospital A.C. Camargo, São Paulo, Brazil
- Corresponding author. Address: Department of Anatomical Pathology, Hospital A.C. Camargo, 109 Professor Antônio Prudente St., Zip Code 01509-900, São Paulo, Brazil. Tel./fax: +55 11 21895185.
Silvia Vanessa Lourenço
- Department of General Pathology, Dental School, University of São Paulo, Brazil
Kátia Candido Carvalho
- Department of Anatomical Pathology, Hospital A.C. Camargo, São Paulo, Brazil
Roberta Cardim
- Department of Head and Neck Surgery, Hospital A.C. Camargo, São Paulo, Brazil
Cláudia Pereira
- Department of Head and Neck Surgery, Hospital A.C. Camargo, São Paulo, Brazil
André Lopes Carvalho
- Department of Head and Neck Surgery, Barretos Cancer Hospital, São Paulo, Brazil
José Humberto Fregnani
- Department of Gynecological Oncology, Barretos Cancer Hospital, São Paulo, Brazil
Fernando Augusto Soares
- Department of Anatomical Pathology, Hospital A.C. Camargo, São Paulo, Brazil
- Department of General Pathology, Dental School, University of São Paulo, Brazil

Received 25 September 2009; received in revised form 19 November 2009; accepted 20 November 2009. published online 11 January 2010.

Summary

Squamous cell carcinoma of the oral cavity (OSCC) is a malignancy characterized by a high degree of local aggression and metastasis to cervical lymph nodes. Tetraspanins are proteins with functional roles in a wide array of cellular processes and are reported to be associated with tumor progression. The present study investigated the expression of the CD9, CD37, CD63, CD81 and CD82 tetraspanins in OSCC using immunohistochemistry (IHC) and quantitative Real Time-PCR (qRT-PCR). Tissue microarray (TMA) analysis of samples from 179 cases of OSCC and 10 normal samples oral mucosa were evaluated immunomorphologically. We analyzed CD9 and CD82 expression by qRT-PCR in 66 OSCC cases and 4 normal samples of oral mucosa. Expression of CD63, CD37 and CD81 was not detected in the samples studied. CD82 was downregulated or negative in 127 of 179 (80%) specimens; no correlation was observed between CD82 expression, clinicopathological parameters, disease-free survival and 5-year overall survival. CD9 expression was downregulated or negative in 75 of 129 (42%) OSCC samples. Loss of CD9 expression in OSCC samples correlated with the incidence of lymph node metastasis (p=0.017). Disease-free survival and the 5-year overall survival of patients with downregulated or negative CD9 expression were significantly lower than in patients with positive CD9 expression (p=0.010 and p=0.071, respectively). No correlation was found between CD9 or CD82 expression and clinicopathological parameters by qRT-PCR. Our results suggest that the downregulation or lack of expression of the CD9 protein might indicate a more aggressive of OSCC.