The expression of the c-erbB-2 receptor protein in glandular salivary secretions.

BACKGROUND: As the maintenance medium of the oral cavity, saliva is secreted from exocrine glands that include the parotid, submandibular, sublingual, and minor salivary glands. Considering that saliva is a fluid suffused with protein, it is possible that the solubilized by-products of oncogenic expression may be present in saliva. Recent studies suggest the presence of solubilized extracellular domain portion of the c-erbB-2 protein in serum, nipple aspirates, and saliva. As a consequence, the purpose of this study was to determine the presence and concentration of c-erbB-2 in major salivary gland secretions. METHODS: Fifteen healthy women had serum, stimulated whole (SWS), parotid (SP), and submandibular/sublingual (SS) salivary secretions collected. The specimens were analyzed for c-erbB-2 using enzyme linked immunosorbent assays (ELISAs). Western blots using c-erbB-2 were also performed on these specimens. RESULTS: The ELISAs revealed the presence of c-erbB-2 in SWS (24.50 Units/ml), SP (19.66 Units/ml), SS (15.59 Units/ml) and serum (1472.15 Units/ml). Western blots confirmed the presence of these 185 kDa proteins. CONCLUSIONS: These results suggest that the protein, c-erbB-2, is present in relatively equal amounts in both SP and SS glandular secretions. Elevated glandular salivary c-erbB-2 concentrations could be useful as a preliminary, non-invasive test in clinical decision making when diagnosing salivary gland carcinomas. Additionally, this marker may have utility in distinguishing between oral lesions that are benign, pre-malignant and malignant in the oral cavity. Further research is required to determine if these findings have clinical utility.

The potential use of saliva to detect recurrence of disease in women with breast carcinoma.

BACKGROUND: Approximately 1 woman in every 10 will develop breast cancer in her lifetime. It has been shown that screening for breast cancer can reduce breast cancer mortality. The use of a saliva-based test could prove to be very useful in post-operative and/or adjunctive therapy management of breast cancer patients. METHODS: The following study was undertaken to establish the possible usefulness of the salivary protein product of the oncogene c-erbB-2 in following patients diagnosed with carcinoma of the breast. Included in this study were 25 patients with a mean age of 54 years with varying histological diagnoses and stages of carcinoma of the breast. ELISA assays for c-erbB-2 and CA 15-3 were performed on serum and stimulated whole saliva samples collected on all patients prior to any adjunct therapy or surgery and sequentially during therapy. RESULTS: The results of the GLM analyses using marker concentration as the dependent variable and treatment regimen and the serial assessments as independent variables yielded a significant overall model for both the serum (P < 0.007) and salivary (P < 0.017) c-erbB-2 markers. The model for serum c-erbB-2, however, exhibited a significant difference for treatment regimen (P < 0.001) with the chemotherapy and radiation treatment regimen being significantly different (P < 0.001) from the other treatment therapies. Time (serial assessments) was not significant. The model for the salivary c-erbB-2 marker was reversed. Treatment regimen was not significant for this model; however, time (serial assessments) was significant (P < 0.002). The serum and salivary CA 15-3 marker models yielded no significant results. Paired t-test analyses indicated that only the salivary c-erbB-2 concentrations exhibited a significant difference between the pre- and post-therapy values (t = 4.245, P < 0.0001). Additionally, salivary c-erbB-2 displayed greater percent reductions across all therapies as compared to the other markers. CONCLUSIONS: This preliminary study appears to indicate that c-erbB-2 protein expression in saliva may be a very useful diagnostic tool for measuring patient response to chemotherapy and/or surgical treatment of their disease.