Carcinogenic potential of tobacco tar-resistant Staphylococcus aureus in buccal cavity.
OBJECTIVE
The effects of cigarette smoking on the association between inflammation and cancer were studied, since some bacteria induce the production of tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine and endogenous tumor promoter, in cells.


METHODS
Bacteria from a gargled solution from the buccal cavity of 20 individuals were cultured in the presence of 4 mg/ml cigarette-smoke condensates. Although cigarette-smoke condensates inhibited growth of Staphylococcus aureus strongly and that of Staphylococcus warneri weakly, tobacco tar-resistant S. aureus and S. warneri were obtained.


RESULTS
One tobacco tar-resistant S. aureus strain (Sa-TA10) induced expression of the TNF-alpha gene in both Bhas 42 cells (v-Ha-ras transfected BALB/3T3 cells) and human lung cancer cell line H226B, while one tobacco tar-resistant S. warneri (Sw-TA75) did not induce it significantly. Moreover, Sa-TA10 induced formation of transformed foci and soft-agar colony in Bhas 42 cells in cooperation with the v-Ha-ras gene. The results suggested that Sa-TA10 has carcinogenic potential, whereas Sw-TA75 does not.


CONCLUSIONS
These data suggest that tobacco tar-resistant S. aureus, with carcinogenic potential, is present in the buccal cavity of some individuals, and that cigarette smoking simultaneously inhibits growth of most of the bacteria and selects carcinogenic bacteria.
Fujiki
H
H
Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima Japan. hfujiki@ph.bunri-u.ac.jp
Takeuchi
H
H
Nishitani
N
N
Yamanaka
H
H
Suzuki
K
K
Kurusu
M
M
Suganuma
M
M
D016475:3T3 Cells / Q000473:pathology; D000328:Adult; D000818:Animals; D002273:Carcinogens / Q000009:adverse effects*; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D002478:Cells, Cultured; D024881:Drug Resistance, Bacterial; D015870:Gene Expression; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009061:Mouth Mucosa / Q000382:microbiology*; D012333:RNA, Messenger / Q000378:metabolism; D013211:Staphylococcus aureus / Q000187:drug effects / Q000254:growth & development* / Q000302:isolation & purification; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
D002273:Carcinogens; D012333:RNA, Messenger; D014028:Tobacco Smoke Pollution; D014409:Tumor Necrosis Factor-alpha