CORRELATION BETWEEN HEAT SHOCK PROTEIN 27 EXPRESSION WITH ESTROGEN RECEPTOR STATUS IN INDONESIAN BREAST CANCER CASES

Introduction: Breast cancer is the second most common cancer in Indonesian women and the most common cancer in women worldwide. Estrogen receptors are one of the most prominent determinants of progressivity and prognosis in breast cancer. Meanwhile, the expression of heat shock proteins, including the downstream estrogen target Hsp27, are shown to be related with antiapoptotic and drug-resistant properties in cancer cells.This study aims to confirm whether Hsp27 overexpression is indeed correlated with estrogen receptor expression, and whether the correlation is statistically significant. Methods: This study was conducted on archived paraffin blocks of breast cancer tissue, dated from January to December 2015, and is a descriptive study complemented by statistical analysis. Results: The expression of estrogen receptors are found to be present in 63.33% of samples. Meanwhile, hsp27 expression scoring is equally divided, with 6.5 as the median score in a range of 0-13. Estrogen receptor expression and hsp27 expression are more prominent in patients aged older than 50 years old, as shown in cross-tabulation data. Spearman Rank Correlation test determines that the Hsp27 score is significantly correlated with staining intensity (p = 0.4209) and stained area (p = 0.044186) of estrogen receptor immunohistochemical status. Similarly, Wilcoxon Rank Sum statistics determines that there exists a statistically significant correlation between Hsp27 score and estrogen receptor positivity (p = 0.0369). Conclusion: The correlation between the expression of Hsp27 and estrogen receptor status is positive and statistically significant. Estrogen receptor positivity and high Hsp27 score are both more prominent in older aged patients.