Study On HER2, TOP2A And Chromosome 17 In Breast Cancer

Purpose:To investigate the relationship between TOP2A protein expression and TOP2A gene abnormal,the relationship amang protein expression and genes of HER2 TOP2A and polysome 17, the relationship between HER2,TOP2A,polysome 17 and clinical parameters.Methods:We analyzed paraffin sections from 60 patients with invasive dula cancer.IHC determined that 1/3 of the patients had HER2 protein expression (0/1+) (2+) (3+) respectively. IHC determined protein expression state of HER2 and TOP2A, while FISH ditermined HER 2 gene status,TOP2A gene status and chromosome 17 status.Results:The score of (0/1+) in IHC identified 95.5%(21of 22cases)of the cases with HER2 non-amplification and 4.5%(1of 22 cases)of the cases with HER2 amplification; the score of (3+) in IHC identified 94.7%(18of 19cases)of the cases with HER2 amplification and 5.3%(lof 19 cases)of the cases with HER2 non-amplification.The concordance of IHC analysis for HER2 protein and FISH analysis for HER2 gene was well (Kappa=0.902, P< 0.05). Normal in chromosome 17 were detected in 42 patients:21.4%(9 of 42 cases) was HER2 protein (3+),78.6%(33 of 42 cases) was HER2 protein (0/1+)and(2+). polysomy 17 were detected in 18 patients:55.6%(9 of 42 cases) was HER2 protein (3+),78.6%(33 of 42 cases) was HER2 protein (0/1+)and(2+).HER2 protein (3+) was more in polysomy 17. Normal in chromosome 17 were detected in 42 patients:47.6%(20 of 42 cases) was HER2 gene amplifition, polysomy 17 were detected in 18 patients:66.7%(12 of 18 cases) was HER2 gene amplification. No statistically significant correlation was found between the two groups. TOP2A protein expression negative were detected in 16 patients:6.3%(1 of 16 cases) was TOP2A gene deletion,87.5%(14 of 16 cases) was TOP2A gene normal,6.3%(1 of 16 cases) was TOP2A gene amplification; TOP2A protein expression positive were detected in 44 patients:0 was TOP2A gene deletion,81.8%(36of 44 cases) was TOP2A gene normal,18.2%(8 of 44 cases) was TOP2A gene amplification; there was no statistically significant correlation between the TOP2A protein expression negative and positive. (x2= 3.909, P=0.142, P>0.05)。Normal in chromosome 17 were detected in 42 patients:69.0% (29 of 42 cases) was TOP2A protein expression positive;polysomy 17 were detected in 18 patients:83.3%(15 of 18 cases) was TOP2A protein expression negative. No statistically significant correlation was found between the two groups. (x 2= 1.315, P>0.05). Normal in chromosome 17 were detected in 42 patients:0 was TOP2A gene deletion,85.7%(36 of 42 cases) was TOP2A gene normal,14.3%(6 of 42 cases) was TOP2A gene amplification; polysomy 17 were detected in 18 patients:5.6% was TOP2A gene deletion,77.8%(14of 18 cases) was TOP2A gene normal,16.7%(3 of 18 cases) was TOP2A gene amplification; there was no statistically significant correlation between the chromosome 17 normal and polysome17. (x2=2.476, P>0.05).21.9% of the HER2 gene amplification samples were found in the group with TOP2A gene amplification,one case (3.1%) showed deletion of TOP2A gene.7.1% of the HER2 gene non-amplificantion samples were found in the group with TOP2A gene amplification, there was no statistically significant correlation between the chromosome 17 normal and polysomel7. (x2=2.476, P>0.05).84.4% of the HER2 gene amplification samples were found in the group with TOP2A protien positive,60.7% of the HER2 gene non-amplificantion samples were found in the group with TOP2A protien positive, there was statistically significant correlation between the chromosome 17 normal and polysome17. (x 2=2.476, P>0.05). HER2 protein and gene positive were faound to be associated with lympy node involvement and prog-esterone/estrogen receptor negativity. TOP2A protein positive were faound to be associated with prog-esterone receptor negativity.Conclusion:1, For HER2 protein (0/1+) and (3+) by IHC, IHC can estimate HER2 protein state, for HER2 protein (2+), FISH must to estimate HER2 gene state.2, There was relation between ploysome 17 and HER2 protein expression.3, There was no relation among TOP2A protein expression TOP2A gene abnormal and ploysome 17.4, there was relation between HER2 gene amplification and TOP2A protein,promping HER2 gene amplification patients should choose anthracycline-based chemotherapy.