Vinblastine, adriamycin, thiotepa, and halotestin (VATH): therapy for advanced breast cancer refractory to prior chemotherapy

Drug repurposing for breast cancer therapy: Old weapon for new battle

Despite tremendous resources being invested in prevention and treatment, breast cancer remains a leading cause of cancer deaths in women globally. The available treatment modalities are very costly and produces severe side effects. Drug repurposing that relate to new uses for old drugs has emerged as a novel approach for drug development. Repositioning of old, clinically approved, off patent non-cancer drugs with known targets, into newer indication is like using old weapons for new battle. The advances in genomics, proteomics and information computational biology has facilitated the process of drug repurposing. Repositioning approach not only fastens the process of drug development but also offers more effective, cheaper, safer drugs with lesser/known side effects. During the last decade, drugs such as alkylating agents, anthracyclins, antimetabolite, CDK4/6 inhibitor, aromatase inhibitor, mTOR inhibitor and mitotic inhibitors has been repositioned for breast cancer treatment. The repositioned drugs have been successfully used for the treatment of most aggressive triple negative breast cancer. The literature review suggest that serendipity plays a major role in the drug development. This article describes the comprehensive overview of the current scenario of drug repurposing for the breast cancer treatment. The strategies as well as several examples of repurposed drugs are provided. The challenges associated with drug repurposing are discussed.

Spontaneous dormancy of metastatic breast cancer cells in an all human liver microphysiologic system

Background:

Metastatic outgrowth in breast cancer can occur years after a seeming cure. Existing model systems of dormancy are limited as they do not recapitulate human metastatic dormancy without exogenous manipulations and are unable to query early events of micrometastases.

Methods:

Here, we describe a human ex vivo hepatic microphysiologic system. The system is established with fresh human hepatocytes and non-parenchymal cells (NPCs) creating a microenvironment into which breast cancer cells (MCF7 and MDA-MB-231) are added.

Results:

The hepatic tissue maintains function through 15 days as verified by liver-specific protein production and drug metabolism assays. The NPCs form an integral part of the hepatic niche, demonstrated within the system through their participation in differential signalling cascades and cancer cell outcomes. Breast cancer cells intercalate into the hepatic niche without interfering with hepatocyte function. Examination of cancer cells demonstrated that a significant subset enter a quiescent state of dormancy as shown by lack of cell cycling (EdU⁻ or Ki67⁻). The presence of NPCs altered the cancer cell fraction entering quiescence, and lead to differential cytokine profiles in the microenvironment effluent.

Conclusions:

These findings establish the liver microphysiologic system as a relevant model for the study of breast cancer metastases and entry into dormancy.

Phase III Study of Standard Combination Versus Rotating Regimen of Induction Chemotherapy in Patients With Hormone Insensitive Metastatic Breast Cancer

OBJECTIVE

The objective of this multicenter phase III trial was to study the impact on time to treatment failure (TTF) and survival of cyclophosphamide, Adriamycin, and 5-fluorouracil (CAF) versus CAF/thiotepa, Adriamycin, vinblastine, and Halotestin (TsAVbH), a partially noncross-resistant regimen used in a rotating schedule in the treatment of hormone insensitive metastatic breast cancer in accordance with the Goldie and Coldman hypothesis.

METHODS

Three hundred forty-three patients received 6 cycles of induction treatment with one of 2 regimens. Patients with estrogen receptor-negative tumors or those with estrogen receptor-positive or estrogen receptor-unknown tumors with demonstrated unresponsiveness to hormone treatment were eligible. Complete responders were randomized to either observation or maintenance therapy with cyclophosphamide, methotrexate, 5-fluorouracil, prednisone, tamoxifen, and Halotestin (CMF[P]TH). Patients with partial response or stable disease on completion of induction therapy were maintained on CMF plus Halotestin.

RESULTS

There were no differences in the primary end point of TTF (median 7.3 and 7.4 months, respectively). There was a significant difference in TTF and survival by duration of disease-free interval: a median of 8.8 and 21.2 months for those with a disease-free interval of > or =2 years versus 6 to 8 and 13.3 months for those with a disease-free interval <2 years (P = 0.016 and <0.001), respectively. Toxicity of the 2 treatment regimens was similar.

CONCLUSION

There were no differences observed in TTF, survival, and toxicities between the 2 treatment arms, both of which contained doxorubicin (Adriamycin) as the most active agent. The results of observation versus maintenance in complete responders were reported separately.

The use of mitoxantrone, 5-fluorouracil and high-dose leucovorin in the treatment of advanced breast cancer

BACKGROUND

Metastatic breast cancer remains an incurable disease; therefore, both the efficacy and the toxicity of palliative chemotherapy are important considerations. Mitoxantrone and 5-fluorouracil (5-FU) with high dose leucovorin are active drugs in the treatment of breast cancer, and both can be given with relatively few side effects. We evaluated the efficacy and toxicity of these agents in a combination regimen for the treatment of metastatic breast cancer.

PATIENTS AND METHODS

In a phase II study, we treated 35 women with metastatic breast cancer with the following regimen: mitoxantrone 12 mg/m2 i.v. day 1; leucovorin 300 mg i.v. over 1 hour followed by 5-FU 350 mg/m2 i.v. push on days 1, 2 and 3; courses repeated every 21 days. Responding patients received a total of 6-8 courses. Most patients were receiving second-line chemotherapy for metastatic breast cancer, but some were receiving first-line therapy following failure of adjuvant chemotherapy.

RESULTS

Twenty of 31 assessable patients (65%) had objective responses; in addition, 2 of 4 patients with bone-only metastases had sustained symptomatic responses. Toxicity was mild and the regimen was well tolerated. The activity of this drug combination has been verified in several other phase II studies.

CONCLUSIONS

The combination of mitoxantrone, 5-FU and high-dose leucovorin provides an attractive option for second-line chemotherapy of metastatic breast cancer. The efficacy of this combination in first-line therapy is currently being compared to cyclophosphamide, methotrexate and 5-FU (CMF) in a randomized trial.

Sequence-dependent growth-inhibitory effects of the in vitro combination of fluorouracil, cisplatin, and dipyridamole

The present study was designed to analyze the growth-inhibitory effects of the combination of fluorouracil (FUra), cisplatin (CDDP), and dipyridamole (DP). These toxic effects were assessed on the human breast-carcinoma cell line MCF-7 using the MTT (tetrazolium bromide) assay in 96-well culture dishes. Data were analyzed using the median-effect principle. The drug combinations tested included FUra concentrations ranging from 0.8 to 800 nmol/l, CDDP concentrations of 0.3-30 mumol/l, and DP concentrations of 2-200 mumol/l. A total of 189 different experimental conditions were tested, including different sequences of administration, with being DP applied before, simultaneously with, or after the two antitumor drugs. Synergistic cytotoxic interactions were found between FUra and CDDP, FUra and DP, and CDDP and DP as well as when the three drugs were combined. The sequence of exposure did not influence the growth-inhibitory activity of the combination FUra-CDDP but altered the effect of combinations of either FUra or CDDP with DP, since at lower concentrations the effect shifted from synergism to antagonism when DP was added simultaneously with CDDP and after the two antitumor drugs. However, the interaction was shown to be truly synergistic by median-effect analysis when the two antitumor drugs were simultaneously associated, with no change in the synergistic effect being observed for the three DP administration sequences.

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.

Comprehensive management of disseminated breast cancer

The management of patients with metastatic breast cancer is best achieved by the judicious use of local and systemic measures that palliate symptoms and improve overall quality of life. When two treatment approaches are known to be equally efficacious, the less toxic should be used. When disease is limited to one or two sites and the patient has an indolent form of the disease, the patient's symptoms are often best palliated with the use of surgery or radiotherapy alone. When multiple sites of disease are evident or the disease is progressing more rapidly, systemic therapy is preferred, and local therapies should be added when the patient is clearly refractory to systemic therapy or when the disease site is unlikely to be adequately palliated with systemic therapy. The use of any of these therapies, including chemotherapy, has a relatively small effect on the median survival of patients with metastatic breast cancer. However, improvements in quality of life are usually greatest with regimens inducing the highest response rates, even when these regimens are associated with greater toxicity. The characteristics of patients likely to respond to endocrine therapy are well defined; in these patients endocrine therapy should be used as the first form of systemic therapy. Among endocrine therapies, the least toxic is used first. The selection of patients for chemotherapy is largely a process of exclusion. When chemotherapy is used, there are a number of different strategies for sequencing chemotherapy that appear to be equally efficacious. In general, patients should be treated with standard doses of drug combinations for a period in excess of 3 months. When used inappropriately, especially in asymptomatic patients, these therapies may actually compromise the patient's quality of life. The use of surgery, radiation therapy, and systemic therapy should be integrated with various types of psychosupport services, especially peer support groups. Patients who want to try new forms of therapy should do so early in the course of the disease when these therapies are most likely to be effective and the patient has the least to lose if the therapy proves ineffective. This is especially true because the use of the most effective regimens at a time when the patient is asymptomatic may mean that the patient is resistant to most or all therapies of proven value when most in need of palliation.

Platinol (CDDP) and continuous intravenous infusion 5-fluorouracil in refractory stage IV breast cancer: a phase II study

Twenty-four patients with refractory Stage IV breast cancer were treated with platinol (100 mg/m2 i.v. Day 1) and 5-fluorouracil (1000 mg/m2 as a continuous infusion over 24 h daily for 5 days). Objective responses occurred in 12 of 24 patients (50%). The median duration of response was 4.9 months. Platinol and 5-fluorouracil in combination are active agents in patients with refractory breast cancer, and clinical trials are warranted in previously untreated patients.

Combination chemotherapy of advanced breast cancer. Comparison of dibromodulcitol, doxorubicin, vincristine, and fluoxymesterone to thiotepa, doxorubicin, vinblastine, and fluoxymesterone: an Eastern Cooperative Oncology Group Study

Two Adriamycin (doxorubicin)-based chemotherapy regimens were investigated in patients with carcinoma of the breast who had failed prior systemic therapy. The two chemotherapy programs, dibromodulcitol, Adriamycin, vincristine, and Halotestin (fluoxymesterone) (DAVH), and thiotepa, Adriamycin, vinblastine, and Halotestin (TAVH), were chosen for comparison on the basis of reported response rates of 40% to 50% with remission durations of 11 months in patients refractory to other cytotoxic chemotherapy. Cycles of DAVH were repeated every 4 weeks. Cycles of TAVH were repeated every 3 weeks. Of 184 patients evaluable for response, 32% of patients treated with DAVH and 38% of patients treated with TAVH had a complete response (CR) or partial response (PR). An additional 5% of patients had nonmeasurable improvement in osseous disease for an overall rate of response (CR + PR + improvement) of 40%. Patients who had previously received cytotoxic chemotherapy for metastatic disease or had early failure after adjuvant therapy had a lower response rate to DAVH, but not to TAVH than those who did not fail prior chemotherapy. Duration of response and survival were similar with the two treatments. There were seven treatment-related deaths, five among patients receiving DAVH and two among patients receiving TAVH. Patients receiving DAVH had significantly more thrombocytopenia and neurologic toxicity than those receiving TAVH. These treatments appear to be reasonable second-line regimens and are good candidates to be used in initial therapy of metastatic disease or adjuvant therapy studies that explore the use of alternating non-cross-resistant combinations with cyclophosphamide, methotrexate, and 5-fluorouracil.

Adriamycin, vinblastine and mitomycin C as second-line chemotherapy in advanced breast cancer

Thirty-six evaluable patients with metastatic measurable breast carcinoma previously treated with CMF or CMFVP were given second-line chemotherapy with Adriamycin, vinblastine, and mitomycin C (AVM), as follows: Adriamycin 20 mg/m2 and vinblastine 6 mg/m2 by i. v. push on days 1, 8, and 15, and mitomycin C 10 mg/m2 i. v. on day 1, every 6 weeks. Ten patients (28%) achieved partial remission (PR) lasting a median of 10 months, and eight patients (22%) experienced improvement of a lesser level than PR. An additional nine patients (25%) had disease stabilization; in the remaining nine patients (25%), persistent disease progression was observed. The median survival from the onset of AVM was 7 months for all patients; patients with PR survived a median of 13 months. Myelotoxicity was substantial and frequently interfered with the optimal administration of AVM, especially in patients with skeletal metastases; four patients were hospitalized with leukopenia and fever; all recovered promptly; one death was probably related to thrombocytopenia and CNS bleeding. Our results with AVM are similar to the average response rate published in the literature with the use of Adriamycin as a single agent in previously treated patients with advanced breast cancer.

Chemotherapy of breast cancer

Carcinoma of the breast will prove fatal to over 37,000 women in the United States in 1983, despite attempts at early diagnosis. Hormonal manipulation, known to provide effective palliation for many years, can now be effectively aimed at receptor positive women who have a 50-70% chance of responding. Newer agents, such as tamoxifen and aminoglutethimide offer the benefits of older treatments with less morbidity. Investigations of drugs acting at the level of the central nervous system are ongoing. Single agent chemotherapy is clearly effective in causing tumor regression, but effective combination chemotherapy provides more responses and a longer duration of response. The most effective combination regimens at present contain doxorubicin. Pharmacologic studies at the cellular level can be expected to provide more effective combinations. The most effective way to combine hormonal and chemotherapeutic treatments is not known. In receptor positive women without life-threatening disease, beginning with hormonal treatment may be effective in providing palliation at low toxic cost without jeopardizing overall survival. New efforts to cure clinically manifest metastatic breast cancer may eschew palliation as a prime goal. Techniques of synchronizing and of stimulating breast cancer to increase its susceptibility to cytotoxic drugs are under investigation. Immunotherapy is not established as a beneficial modality in the treatment of breast cancer, although levamisole has led to suggestive benefit in small controlled trials. The use of chemotherapy, and possibly of some hormonal treatments in appropriate patients, as an adjuvant to surgery prolongs disease-free survival. This approach, using established chemotherapeutic and hormonal agents when the metastatic disease is subclinical, is consonant with abundant evidence from experimental systems and other human cancers that are curable. Expectation of curing human breast cancer will likely require aggressive action at the time when the total body tumor burden is at a minimum.

5-Fluorouracil + Oncovin + Adriamycin + mitomycin C (FOAM): an effective program for breast cancer, even for disease refractory to previous chemotherapy. A Northern California Oncology Group (NCOG) Study

One hundred and thirty-one patients (118 evaluable) with disseminated breast cancer were treated with a combination of 5-fluorouracil + Oncovin + Adriamycin + mitomycin C (FOAM). The objective response rate for 82 evaluable patients whose disease was refractory to previous CMF or L-PAM chemotherapy was 35%; that for 36 evaluable patients who had not previously received chemotherapy, 56%. The hematologic toxicity of this therapy was generally mild and acceptable. It is believed that FOAM is an effective therapy for patients whose tumors are resistant to CMF.

Chemotherapy of breast cancer: current views and results

The paper critically reviews major accomplishments achieved with the use of chemotherapy in the treatment of various stages of breast cancer. In spite of innumerable clinical trials, there is no evidence that in advanced breast cancer the addition of more drugs, either in concomitant, sequential or alternating fashion, to known effective combinations, was able to significantly improve the incidence and the magnitude of objective response or its median duration or survival. The addition of endocrine therapy to chemotherapy has failed so far to improve the most important end-point, i.e. total survival. Second-line chemotherapy is only moderately effective for a fairly short period of time. Thus, in women with advanced breast cancer excessive tumor cell burden and permanent drug resistance remain the major obstacles to obtaining complete remission and long-term disease free survival. In the adjuvant setting, the initial trials with combination chemotherapy have achieved consistent results, particularly in women with minimal axillary node involvement. Unless a woman has undergone a surgical breast-saving procedure, postoperative radiotherapy does not appear to play an important therapeutic role, either with or without concomitant or sequential chemotherapy. Present results would suggest that in advanced breast cancer little progress can be expected in the near future. Therefore, medical oncologists should focus on the correct application of established drug regimens, using a sequential flow of hormonal manipulations and cytotoxic chemotherapy. In high-risk groups, full dose adjuvant polydrug therapy given for a relatively short period of time appears to be at present the only means able to significantly decrease the failure rate following local regional treatment. Present consistent achievements, which appear devoid of important delay morbidity (e.g. cancerogenesis, chronic organ damage) will require further clinical research to identify more effective and less toxic treatments.

Vincristine, adriamycin, and mitomycin (VAM) therapy for previously treated breast cancer. A preliminary report

Fifteen patients with metastatic breast cancer previously treated with chemotherapy were treated with a regimen consisting of vincristine, Adriamycin, and mitomycin. Eleven patients (73%) responded with three complete and eight partial responses. The median duration of response was eight months. While all four nonresponders died within five months, the median duration of survival of responders was 18 months. Toxicity was significant but tolerable. Thus, this preliminary report suggests that this regimen is active in advanced previously treated breast cancer, providing meaningful remissions with acceptable toxicity.

One-day VATH (vinblastine, Adriamycin, thiotepa, and Halotestin) therapy for advanced breast cancer refractory to chemotherapy

Twenty-nine postmenopausal patients with metastatic breast cancer refractory to conventional combination chemotherapy underwent treatment with a combination of vinblastine, Adriamycin, thiotepa, and Halotestin given once every 21 days. Thirteen patients (45%) responded with a greater than 50% regression of measurable tumor. Responses occurred in nine of 12 patients (75%) with visceral dominant disease and were recognized in four of 15 (27%) with osseous dominant disease (another 5 improved for a total improvement of 60%). The median duration of response was 11 months. The median survival times were 16 months for responders and eight months for those with progressive disease. Response rate was not affected by age, number of years after menopause, number of metastatic sites involved, or number of systemic treatment modalities previously used, but may have been adversely affected by late stage at original diagnosis, short time from diagnosis, poor response to primary chemotherapy, and dose modification. This combination of drugs is a convenient, tolerable, and effective regimen for treating breast cancer refractory to primary chemotherapy regimens currently in use.

Advanced breast cancer - additive hormonal therapy

Increased response rates with nonhormonal combination chemotherapy have led many oncologists to deprecate the use of hormonal therapy in the management of advanced breast cancer. The estrogen and progesterone receptor assay, on the one hand, has restimulated the enthusiasm for hormonal therapy when positive, but conversely when negative suggests that their use is precluded from further consideration. The author's thoughts on the continuing employment of additive hormonal therapy for almost all patients, either singly or in combination with other hormonal and nonhormonal drugs, with minimal restrictions imposed by hormonal assays or sites of disease will be presented. A short review of estrogen, androgens, progestins, Teslac, and corticosteroids will be offered. The ease of administration of hormones and the increase in recurrent disease survival in responders compared with nonhormonal therapy strongly indicate that additive hormonal therapy still has a major role in the management of the advanced breast cancer patient.