Paclitaxel, vinorelbine and 5-fluorouracil in breast cancer patients pretreated with adjuvant anthracyclines

Redefining the Incidence and Profile of Fluoropyrimidine-Associated Cardiotoxicity in Cancer Patients: A Systematic Review and Meta-Analysis

Aim: The cardiac toxicity that occurs during administration of anti-tumor agents has attracted increasing concern. Fluoropyrimidines have been used for more than half a century, but their cardiotoxicity has not been well clarified. In this study, we aimed to assess the incidence and profile of fluoropyrimidine-associated cardiotoxicity (FAC) comprehensively based on literature data. Methods: A systematic literature search was performed using PubMed, Embase, Medline, Web of Science, and Cochrane library databases and clinical trials on studies investigating FAC. The main outcome was a pooled incidence of FAC, and the secondary outcome was specific treatment-related cardiac AEs. Random or fixed effects modeling was used for pooled meta-analyses according to the heterogeneity assessment. PROSPERO registration number: (CRD42021282155). Results: A total of 211 studies involving 63,186 patients were included, covering 31 countries or regions in the world. The pooled incidence of FAC, by meta-analytic, was 5.04% for all grades and 1.5% for grade 3 or higher. A total of 0.29% of patients died due to severe cardiotoxicities. More than 38 cardiac AEs were identified, with cardiac ischemia (2.24%) and arrhythmia (1.85%) being the most frequent. We further performed the subgroup analyses and meta-regression to explore the source of heterogeneity, and compare the cardiotoxicity among different study-level characteristics, finding that the incidence of FAC varied significantly among different publication decades, country/regions, and genders. Patients with esophagus cancer had the highest risk of FAC (10.53%), while breast cancer patients had the lowest (3.66%). The treatment attribute, regimen, and dosage were significantly related to FAC. When compared with chemotherapeutic drugs or targeted agents, such a risk was remarkably increased (χ2 = 10.15, p < 0.01; χ2 = 10.77, p < 0.01). The continuous 5-FU infusion for 3–5 consecutive days with a high dosage produced the highest FAC incidence (7.3%) compared with other low-dose administration patterns. Conclusions: Our study provides comprehensive global data on the incidence and profile of FAC. Different cancer types and treatment appear to have varying cardiotoxicities. Combination therapy, high cumulative dose, addition of anthracyclines, and pre-existing heart disease potentially increase the risk of FAC.

New Uracil Analog with Exocyclic Methylidene Group Can Reverse Resistance to Taxol in MCF-7 Cancer Cells

Introduction

Taxol (Tx), a microtubule-stabilizing drug, has been widely used as a chemotherapeutic in several types of cancer. However, the development of resistance limited its application. One of the strategies used to prevent the emergence of drug resistance is combination treatment, involving at least two drugs. The aim of the current study was to assess if a new uracil analog, 3-p-bromophenyl-1-ethyl-5-methylidenedihydrouracil (U-359) can prevent the development of Tx resistance in breast cancer cells.

Methods

The cytotoxicity of the new drug was tested in MCF-7 (hormone receptor (ER, PR) positive cell-line) and MCF-10A cell lines using MTT method. For the detection of apoptosis and necrosis, the Wright and Giemsa staining was used. Gene expression was measured by real-time PCR, and changes in the protein levels were evaluated by ELISA and bioluminescent method.

Results

We investigated the effect of Tx and U-359 on cancer MCF-7 and normal MCF-10A cells alone and in combination. Tx co-administered with U-359 inhibited proliferation of MCF-7 cells to 7% while the level of ATPase drastically decreased to 14%, compared with effects produced by Tx alone. The apoptosis process was induced through the mitochondrial pathway. These effects were not seen in MCF-10A cells, showing the wide safety margin. The obtained results have shown that U-359 produced a synergistic effect with Tx probably by reducing Tx resistance in MCF-7 cells. To elucidate the possible mechanism of resistance, expression of tubulin III (TUBIII), responsible for microtubule stabilization and tau and Nlp proteins, responsible for microtubule dynamics, was assessed.

Conclusion

Combination of Tx with U-359 reduced overexpression of TUBIII and Nlp. Thus, U-359 may stand for a potential reversal agent for the treatment of MDR in cancer cells.

Co-Delivery of 5-Fluorouracil and Paclitaxel in Mitochondria-Targeted KLA-Modified Liposomes to Improve Triple-Negative Breast Cancer Treatment

In this research, KLA-modified liposomes co-loaded with 5-fluorouracil and paclitaxel (KLA-5-FU/PTX Lps) were developed, and their antitumor activity against triple-negative breast cancer (TNBC) was evaluated. KLA-5-FU/PTX Lps were prepared using the thin-film dispersion method, and their in vitro anticancer efficacy was assessed in human breast cancer cells (MDA-MB-231). An MDA-MB-231 tumor-bearing mouse model was also established to evaluate their antitumor efficacy in vivo. KLA-5-FU/PTX Lps showed enhanced cytotoxicity against MDA-MB-231 cells, improved drug delivery to mitochondria, and induced mitochondria-mediated apoptosis. The modified liposomes also showed favorable antitumor activity in vivo due to their strong ability to target tumors and mitochondria. The liposomes showed no obvious systemic toxicity. Our results suggest that KLA-5-FU/PTX Lps are a promising system with which to target the delivery of antitumor drugs to mitochondria as a treatment for TNBC.

Two Antagonistic Microtubule Targeting Drugs Act Synergistically to Kill Cancer Cells

Paclitaxel is a microtubule stabilizing agent and a successful drug for cancer chemotherapy inducing, however, adverse effects. To reduce the effective dose of paclitaxel, we searched for pharmaceutics which could potentiate its therapeutic effect. We screened a chemical library and selected Carba1, a carbazole, which exerts synergistic cytotoxic effects on tumor cells grown in vitro, when co-administrated with a low dose of paclitaxel. Carba1 targets the colchicine binding-site of tubulin and is a microtubule-destabilizing agent. Catastrophe induction by Carba1 promotes paclitaxel binding to microtubule ends, providing a mechanistic explanation of the observed synergy. The synergistic effect of Carba1 with paclitaxel on tumor cell viability was also observed in vivo in xenografted mice. Thus, a new mechanism favoring paclitaxel binding to dynamic microtubules can be transposed to in vivo mouse cancer treatments, paving the way for new therapeutic strategies combining low doses of microtubule targeting agents with opposite mechanisms of action.

Vinorelbine and fluorouracil plus leucovorin combination (ViFL) in patients with anthracycline and taxane-pretreated metastatic breast cancer: a phase II study

PURPOSE

This phase II study was designed in order to evaluate efficacy and safety of the combination of vinorelbine (VNB), fluorouracil (FU) and leucovorin (LV) in patients with metastatic breast carcinoma (MBC) previously treated with anthracyclines and taxanes.

METHODS

From 12/2003 to 12/2007, 51 women (median age 59) were treated. Performance status (PS) (ECOG) was 0-2 (median 0). The chemotherapy consisted of VNB 25 mg/sqm on day 1 added to FU and LV (following De Gramont schedule) on day 1 and 2. Treatment was repeated every 14 days. 518 cycles of CT were administered (median 12). Most common sites of metastatic spread were: bone, liver, lymph nodes, lung.

RESULTS

We recorded three cases of G4 neuthropenia and in one case it was febrile; no others G4 toxicities were seen. G3 toxicities were more common, especially neuthropenia (8 patients) asthenia (4) mucositis (2) and Hand-Foot Syndrome (2). Overall response rate was 27.5% (14 patients had a PR) and disease control rate was 76.5%; 12 patients experienced disease progression. Median time to progression (TTP) was 7.70 months and overall survival (OS) was 18.70 months.

CONCLUSIONS

Results demonstrate that the ViFL regimen has substantial activity in patients with MBC already treated with anthracyclines and taxanes. The combination may be considered a valid choice for the treatment of MBC. Better survival results were seen in patients with visceral metastases than bone involvement. The low response rate shows that the ViFL regimen is not suitable for the neoadjuvant setting.