An evaluation of the effect of vincristine added to cyclophosphamide, 5-fluorouracil, methotrexate, and prednisone in advanced breast cancer

Drug Combination in Cancer Treatment-From Cocktails to Conjugated Combinations

It is well recognized today that anticancer drugs often are most effective when used in combination. However, the establishment of chemotherapy as key modality in clinical oncology began with sporadic discoveries of chemicals that showed antiproliferative properties and which as a first attempt were used as single agents. In this review we describe the development of chemotherapy from its origins as a single drug treatment with cytotoxic agents to polydrug therapy that includes targeted drugs. We discuss the limitations of the first chemotherapeutic drugs as a motivation for the establishment of combined drug treatment as standard practice in spite of concerns about frequent severe, dose limiting toxicities. Next, we introduce the development of targeted treatment as a concept for advancement within the broader field of small-molecule drug combination therapy in cancer and its accelerating progress that was boosted by recent scientific and technological progresses. Finally, we describe an alternative strategy of drug combinations using drug-conjugates for selective delivery of cytotoxic drugs to tumor cells that potentiates future improvement of drug combinations in cancer treatment. Overall, in this review we outline the development of chemotherapy from a pharmacological perspective, from its early stages to modern concepts of using targeted therapies for combinational treatment.

β-Elemene Enhances the Chemotherapeutic Effect of 5-Fluorouracil in Triple-Negative Breast Cancer via PI3K/AKT, RAF-MEK-ErK, and NF-κB Signaling Pathways

Background

The most common chemotherapeutic drug for triple-negative breast cancer (TNBC) treatment is 5-fluorouracil (5-FU), but its therapeutic index is low due to its toxicity. β-Elemene (ELE) possesses antitumor activity against different cancers, but it has never been used in combination with 5-FU to improve its chemotherapeutic effect against TNBC.

Materials and Methods

We treated MDA-MB-231 and BT549 cells of TNBC with ELE alone, 5-FU alone, or their combination to investigate their treatment effects on cell viability, proliferation, migration, invasion, and colony formation. We verified the molecular mechanisms of our results through confocal immunofluorescence, immunohistochemistry, and Western blot analysis in vitro and in vivo.

Results

Our result revealed that ELE enhanced the 5-FU effect against cell viability, proliferation, migration, invasion, and colony formation through different mechanisms in MDA-MB-231 and BT549 cell lines. In molecular mechanisms, ELE and 5-FU in combination enhances apoptosis in both cell lines through Bl-2 family protein and caspase cascade modulation, thereby inhibiting NF-kB pathway through IKKβ, IKKα, and p65 downregulation in the cytoplasm and p50 and p65 downregulation in the nucleus. ELE and 5-FU in combination regulated the PI3K/AKT pathway through p-AKT, P-85, p110r, p-PDK1, and p110a protein and RAF-MEK-ERK pathway inhibition through the p-c-raf and p-ERK downregulation. The PI3K inhibitor LY294002 or RAF-MEK-ERK inhibitor U0126 in combination with ELE and 5-FU decreased cell viability in both cell lines significantly, thereby showing the involvement of these pathways in cell apoptosis. In mouse xenograft model, ELE and 5-FU in combination inhibited the tumor growth and modulated its molecular markers.

Conclusion

The conclusion obtained, considering that the results suggest that the combination may be important specifically in the treatment of TNBC.

Addition of drug/s to a chemotherapy regimen for metastatic breast cancer

BACKGROUND

The addition of a chemotherapy drug or drugs to an established regimen is one method used to increase the dose and intensity of treatment for metastatic breast cancer.

OBJECTIVES

To assess the effects of adding one or more chemotherapy drugs to an established regimen in women with metastatic breast cancer.

SEARCH STRATEGY

We searched the Cochrane Breast Cancer Group's Specialised Register (to August 2009) using the codes for "advanced breast cancer" and "chemotherapy". This review is an update of the original Cochrane Review (Issue 3, 2006).

SELECTION CRITERIA

Randomised trials with a first line regimen of at least two chemotherapy drugs compared to the same regimen plus the addition of one or more chemotherapy drugs in women with metastatic breast cancer.

DATA COLLECTION AND ANALYSIS

Two authors extracted data independently from published trials. We derived hazard ratios (HR) from time-to-event outcomes where possible, and used a fixed-effect model for meta-analysis. We analysed response rates as dichotomous variables and extracted toxicity data where available.

MAIN RESULTS

We identified 17 trials reporting on 22 treatment comparisons (2674 patients randomised). Fifteen trials (20 treatment comparisons) reported results for tumour response and 11 trials (14 treatment comparisons) published time-to-event data for overall survival. There were 1532 deaths in 2116 women randomised to trials of the addition of a drug to the regimen and control (the regimen alone). There was no detectable difference in overall survival between these patients, with an overall HR of 0.96 (95% confidence interval (CI) 0.87 to 1.07, P = 0.47) and no significant heterogeneity. We found no difference in time to progression between these regimens, with an overall HR of 0.93 (95% CI 0.81 to 1.07, P = 0.31) and no significant heterogeneity. Addition of a drug to the regimen was favourably associated with overall tumour response rates (odds ratio 1.21, 95% CI 1.01 to 1.44, P = 0.04) although we observed significant heterogeneity for this outcome across the trials. Where measured, acute toxicities such as alopecia, nausea and vomiting and leucopenia were more common with the addition of a drug.

AUTHORS' CONCLUSIONS

The addition of one or more drugs to the regimen shows a statistically significant advantage for tumour response in women with metastatic breast cancer but the results suggest no difference in survival time or time to progression. The positive effect on tumour response was also associated with increased toxicity.

Addition of drug/s to a chemotherapy regimen for metastatic breast cancer

BACKGROUND

The addition of a chemotherapy drug or drugs to an established regimen is one method used to increase the dose and intensity of treatment for metastatic breast cancer.

OBJECTIVES

To identify and review the randomised trial evidence in the first line management of women with metastatic breast cancer that evaluates the addition of one or more chemotherapy drugs to an established regimen.

SEARCH STRATEGY

We searched the specialised register maintained by the Editorial Base of the Cochrane Breast Cancer Group on 3rd August 2004 (updated search on 2nd August 2005) using the codes for "advanced breast cancer" and "chemotherapy". Details of the search strategy applied by the Group to create the register, and the procedure used to code references, are described in the Group's module on the Cochrane Library.

SELECTION CRITERIA

Randomised trials that evaluated a first line regimen of at least two chemotherapy drugs, and compared it to that same regimen plus the addition of one or more chemotherapy drugs in women with metastatic breast cancer.

DATA COLLECTION AND ANALYSIS

We collected data from published trials and assessed studies for eligibility and quality. Two reviewers extracted data independently. We derived hazard ratios (HR) from time-to-event outcomes where possible, and a fixed effect model was used for meta-analysis. We analysed response rates as dichotomous variables and extracted toxicity data where available.

MAIN RESULTS

We identified 17 trials reporting on 22 treatment comparisons (2674 patients randomised). Fifteen trials (20 treatment comparisons) reported results for tumour response and 11 trials (14 treatment comparisons) published time-to-event data for overall survival. There were 1532 deaths in 2116 women randomised to trials of the addition of a drug to the regimen and control (the regimen alone). There was no detectable difference in overall survival between these patients, with an overall HR of 0.96 (95% CI 0.87 to 1.07, P = 0.47) and no statistically significant heterogeneity. We found no difference in time to progression between these regimens, with an overall HR of 0.93 (95% CI 0.81 to 1.07, P = 0.31) and no statistically significant heterogeneity. Addition of a drug to the regimen was favourably associated with overall tumour response rates (OR 1.21, 95% CI 1.01 to 1.44, P = 0.04) although we observed statistically significant heterogeneity for this outcome across the trials. Where measured, acute toxicities such as alopecia, nausea and vomiting and leukopenia were more common with the addition of a drug.

AUTHORS' CONCLUSIONS

The addition of one or more drugs to the regimen shows a statistically significant advantage for tumour response in women with metastatic breast cancer but the results suggest no difference in survival time or time to progression. The positive effect on tumour response observed with addition of a drug to the regimen was also associated with increased toxicity.

The role of the liposomal anthracyclines and other systemic therapies in the management of advanced breast cancer

For patients whose breast cancers are not responsive to endocrine therapy, there are a large number of cytotoxic drugs that will induce a response. In spite of the introduction of new, very active drugs such as the taxanes, vinorelbine, capecitabine, gemcitabine, and trastuzumab, the anthracyclines are still as active as any--and more active than most--drugs used to treat breast cancer. Their inclusion in combinations to treat early and advanced disease prolongs survival. However, they cause nausea, vomiting, alopecia, myelosuppression, mucositis, and cardiomyopathies. There is no evidence that increasing the dose of conventional anthracyclines or any other of the cytotoxics beyond standard doses will improve outcomes. Schedule may be more important than dose in determining the benefit of cytotoxics used to treat breast cancer. Weekly schedules and continuous infusions of 5-fluorouracil and doxorubicin may have some advantages over more intermittent schedules. Liposomal formations of doxorubicin reduce toxicity, including cardiotoxicity; theoretically they should also be more effective because of better targeting of tumor over normal tissues. Both pegylated liposomal doxorubicin (Doxil/Caelyx [PLD]) and liposomal doxorubicin (Myocet [NPLD]) appeared to be as effective as conventional doxorubicin and much less toxic in multiple phase II and phase III studies. PLD has been evaluated in combinations with cyclophosphamide, the taxanes, vinorelbine, gemcitabine, and trastuzumab, and NPLD has been evaluated in combination with cyclophosphamide and trastuzumab. Both liposomal anthracyclines are less cardiotoxic than conventional doxorubicin. The optimal dose of PLD is lower than that of conventional doxorubicin or NPLD. Patients treated with PLD have almost no alopecia, nausea, or vomiting, but its use is associated with stomatitis and hand-foot syndrome, which can be avoided or minimized with the use of proper dose-schedules. In contrast, the optimal dose-schedule of NPLD is nearly identical to that of conventional doxorubicin. The toxicity profile of NPLD is similar to that of conventional doxorubicin, but toxicities are less severe and NPLD is better tolerated than conventional doxorubicin at higher doses.

The clinical pharmacology and use of antimicrotubule agents in cancer chemotherapeutics

Although there has been a rapid expansion of the number of classes of compounds with antineoplastic activity, few have played a more vital role in the curative and palliative treatment of cancers than the antimicrotubule agents. Although the vinca alkaloids have been the only subclass of antimicrotubule agents that have had broad experimental and clinical applications in oncologic therapeutics over the last several decades, the taxanes, led by the prototypic agent taxol, are emerging as another very active class of antimicrotubule agents. After briefly reviewing the mechanisms of antineoplastic action and resistance, this article comprehensively reviews the clinical pharmacology, therapeutic applications, and clinical toxicities of selected antimicrotubule agents.

A comparison of continuation versus late intensification followed by discontinuation of chemotherapy in advanced breast cancer. A prospective randomized trial of the Italian Oncology Group for Clinical Research (G.O.I.R.C.)

One hundred ninety-eight postmenopausal women with metastatic breast carcinoma were entered in this study. After six induction cycles with cyclophosphamide, methotrexate and 5-fluorouracil (CMF), patients with at least stable disease were randomized to the "continuation arm" (continuation of CMF until progression) (A, 49 evaluable patients) or to the "intensification-discontinuation arm" (addition of adriamycin and vincristine to two of the three drugs of CMF for six more cycles; i.e., CMAV, CFAV, MFAV, twice; discontinuation of chemotherapy; radiotherapy to pre-study sites of disease in patients prospectively considered as candidates to receive this treatment) (B, 46 evaluable patients). After randomization, escalation of response category occurred in five patients on A (10%) and in five on B (11%). Time to progression was transiently delayed in arm B within 6 months after randomization. There were no significant differences in the overall time to progression, duration of response or survival. On arm B, after discontinuation of chemotherapy, median time to relapse was 22 weeks. This time was significantly longer in patients who were candidates for radiation therapy (36 weeks, P = 0.005), or with a disease-free interval greater than 1 year (32 weeks, P = 0.004) or who achieved complete remission (60 weeks, P = 0.0001). On arm B, three patients (7%) are still alive in complete remission in excess of three, five and six years following discontinuation of therapy. This study indicates that late intensification of chemotherapy followed by discontinuation of treatment may maintain palliation, and allow a long treatment-free period in responding patients with advanced breast carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)