Expression of C-KIT and HER-2 tyrosine kinase receptors in poor-prognosis breast cancer.
BACKGROUND
This study investigated the expression of C-KIT and HER-2 receptors and their correlation with histopathological markers of cell proliferation, differentiation and apoptosis in poor-prognosis breast cancer.


METHODS
Formalin-embedded histopathological samples from forty patients with progressive metastatic breast cancer were reanalyzed to determine HER-2 expression by immunohistochemistry (ICH) and chromogenic in situ hybridization (CISH). C-KIT receptor expression, p53, Bcl-2 and Ki-67 were determined by immunohistochemistry.


RESULTS
The mean p53 score was 18.03 (SD 30.69), that of Bcl-2 was 38.13 (39.25) and Ki-67 was 5.8 (SD 9.23), respectively. HER-2 expression was positive in 35% of patients by ICH and in 25% by CISH. C-KIT receptor staining was positive in 82% of the patients. A significant association was observed between HER-2-positive score in ICH and poorly-differentiated histology (p=0.03), negative Er/Pr status (p=0.04) and Bcl-2 expression (p=0.003). With CISH-determined HER-2, the corresponding p values were 0.07, 0.053, and 0.002, respectively. No correlation was found between HER-2 or C-KIT expression (p=0.456).


CONCLUSIONS
CISH and ICH determination of HER-2 correlate similarly to hormone receptor status and Bcl-2 expression in breast cancer. C-KIT expression was commonly present and did not correlate to other prognosticators in poor-prognosis breast cancer.
Palmu
S
S
Department of Oncology, University of Turku, Finland.
Söderström
K O
KO
Quazi
K
K
Isola
J
J
Salminen
E
E
D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000502:physiology; D001943:Breast Neoplasms / Q000201:enzymology* / Q000473:pathology; D002454:Cell Differentiation / Q000502:physiology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis*
D019009:Proto-Oncogene Proteins c-kit; D018719:Erb-b2 Receptor Tyrosine Kinases