c‐erbb growth‐factor‐receptor proteins in ovarian tumours

Immunohistochemical expression of EGF‐R, c‐erbB‐2 and c‐erbB‐3, members of the type‐l family of receptor tyrosine kinases, were investigated in 67 primary ovarian‐tumour samples (46 malignant, 8 borderline and 13 benign), and related to tumour clinicopathological features. The incidence of all 3 receptor proteins was highest in overtly malignant tumours. No significant correlations were observed between either EGF‐R or c‐erbB‐3 and clinical parameters such as tumour stage, differentiation or extent of debulking surgery, but c‐erbB‐2 was significantly associated with several indicators of prognosis, including early stage and good/moderate differentiation in optimally debulked tumours. Multiple expression of c‐erbB receptor proteins was also significantly higher in malignant tumours compared with borderline and benign tumours. Early‐stage tumours were also more likely to express multiple c‐erbB‐receptor proteins than were late‐stage tumours. Co‐expression of EGF‐R with c‐erbB‐2, and c‐erbB‐2 with c‐erbB‐3 was significantly greater in malignant tumours than in borderline or benign tumours, and within the malignant tumour group, positive associations were observed between EGF‐R and c‐erbB‐3, also between c‐erbB‐2 and c‐erbB‐3. Because of the evidence of increased expression of individual c‐erbB proteins as well as multiple expression of this family of growth‐factor receptors in malignant ovarian tumours, we hypothesize that stimulation by the appropriate ligands may confer a selective advantage to cells expressing more than one receptor. Increased expression of c‐erbB growth‐factor receptors in malignancy may mediate increased propensity for tumour development. © 1995 Wiley‐Liss, Inc.