Abstract: [Abstract] Objective  To investigate the relationship between the expression of P53 and the prognosis and plati? num-based chemosensitivity in triple negative breast cancer (TNBC). Methods  A total of 291 fresh breast cancer samples were collected . The collagen gel droplet embedded culture drug sensitivity tests (DC-DST) were used to measure the different chemosensitivities of usual chemotheray drugs including docetaxel, epirubicin, pirarubicin navelbine and cisplatin in cultured primary cells in vitro. The expression of P53 was tested by immunohistochemistry. The relationship between P53 expression and clinicopathological characteristics and prognosis was analyzed. The full clinical and follow-up data and biological indicator results in 153 patients with TNBC were retrospectively collected.The Cox regression analysis was used to detect the factors affecting tumor-free survival in patients. Results  There were 43 TNBC patients in 291 patients with primary breast cancer. There was a higher rate of P53 expression (62.79% ，27/43) in patients with TNBC than that of patients with non-TNBC (30.65%，76/248). The positive expression of P53 was higher in patients with grade Ⅲ breast cancer (66.04%) than that in patients with gradeⅠ(23.73%) and gradeⅡ(30.17%) breast cancer. The expression of P53 was an independent factor influencing tumor-free survival in patients with TNBC. There was a significantly lower 5-year tumor-free survival rate in patients with the positive expression of P53 than that of patients with negative expression of P53 (69.70% vs 89.40%, P= 0.001). The positive rate of P53 expression was significantly lower in patients with TNBC who were sensitive to cisplatin than that in patients with drug-resistance (P =0.018). Conclusion  The positive expression of P53 suggests a poor prognosis in TNBC patients. The expression of P53 is negatively correlated with the chemosensitivity of platinum-based chemotherapy.

Key words: breast neoplasms, tumor suppressor protein p53, platinum compounds, prognosis, survival analysis, chemosensitivity