This study is a multicenter single-arm, phase II study primarily aimed at assessing the anti-tumor activity of pre-operative zoledronate measured through its effect on the Ki67 proliferative surrogate biomarker, in patients with TNBC classified according to the p53 expression (high vs low p53 expression). An high level of p53 is defined by IHC expression ≥30%, while a low level is defined by IHC expression <30%, as previously described. Patients with newly diagnosed, untreated, operable TNBC, intended to definitive breast surgery and suitable for pre-operative therapy will be registered using a centralized system and will receive a pre-operative, single administration of zoledronate (4mg i.v.), 7 days before definitive breast surgery . Ki67 levels will be assessed in core biopsy tumor samples collected at the time of diagnosis and after zoledronate treatment at the time of definitive surgery. Primary endpoint of the study is the proportion of responder patients, defined as those with at least 30% reduction in Ki67 at surgery with respect to core-biopsy analysis. The secondary objective of the study is to investigate the effect of zoledronate on critical genes/proteins related to p53 and mevalonate pathways, p53/PIN1 and YAP/TAZ, analyzed in the tumor tissue at the time of diagnosis (core biopsy) and at definitive surgery. The safety profile of zoledronate will be evaluated by the National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) scale, version 4.0 and by the occurrence of serious adverse reactions. The total number of patients required is forty. The overall duration of the project is expected to be 32 months, divided as follows: 30 months for accrual, followed by 2 months of follow-up after the recruitment of the last patient, aimed to collect data on zoledronate safety and tolerability. The primary analysis will be conducted on the PP population which will include all patients registered, who received the dose of study treatment and underwent definitive breast surgery, with no major violations of the eligibility criteria or during study conduction. Proportion of responder patients, defined as those with at least 30% reduction in Ki67 at surgery with respect to core-biopsy analysis, will be presented as point estimate and 95% confidence intervals (95% CIs) for each group. Logistic regression techniques will be used to compare groups in univariate and multivariate model adjusted for ECOG-PS, sex and pre- and postmenopausal status. The results of this project may eventually contribute to unveil novel anticancer mechanism of action of BPs and new therapeutic options for triple negative breast cancer.