• 5/7/2006
  • Samuel J. Hooper et al.
  • Journal of Clinical Microbiology, May 2006, p. 1719-1725, Vol. 44, No. 5

Despite increasing interest in the possible relationships between bacteria and the different stages of cancer development, the association of bacteria with cancer of the oral cavity has yet to be adequately examined. With that in mind, the primary objective of this study was to identify any bacterial species within oral squamous cell carcinoma tissue using a standard microbiological culture approach.

At the time of surgery, a 1-cm3 portion of tissue was harvested from deep within the tumor mass using a fresh blade for each cut. Whenever possible, “superficial” portions from the mucosa overlying the tumor and nontumorous control specimens from at least 5 cm away from the primary tumor site were also obtained.

Surface contamination was eliminated by immersion in Betadine and washing with phosphate-buffered saline. Each specimen was aseptically macerated and cultured on nonselective media under both aerobic and anaerobic conditions. Isolates were identified by 16S rRNA gene sequencing.

Twenty deep-tissue specimens, 19 with corresponding superficial tissues and 12 with control tissues, were successfully processed. A diversity of bacterial taxa were isolated and identified, including several putatively novel species. Most isolates were found to be saccharolytic and acid-tolerant species. Notably, some species were isolated only from either the tumorous or nontumorous tissue type, indicating a degree of restriction.

Successful surface decontamination of the specimens indicates that the bacteria detected were from within the tissue. A diversity of bacterial groups have been isolated from within oral squamous cell carcinoma tissue. The significance of these bacteria within the tumor warrants further study.

Authors:
Samuel J. Hooper,1 St John Crean,2 Michael A. O. Lewis,1 David A. Spratt,3 William G. Wade,4 and Melanie J. Wilson1

Authors’ affiliations:
Department of Oral Surgery, Medicine & Pathology, Cardiff University, Cardiff CF14 4XY, United Kingdom,1 North Glamorgan NHS Trust, Prince Charles Hospital, Merthyr Tydfil CF47 9DT, United Kingdom,2 Division of Microbial Diseases, Eastman Dental Institute, UCL, 256 Gray’s Inn Rd., London WC1X 8LD, United Kingdom,3 King’s College London Dental Institute at Guy’s, King’s College and St. Thomas’ Hospitals, Infection Research Group, London SE1 9RT, United Kingdom4