Phase II evaluation of cisplatin and WR2721 for refractory metastatic breast cancer

Prospective Evaluation of a Circulating Tumor Cell Sensitivity Profile to Predict Response to Cisplatin Chemotherapy in Metastatic Breast Cancer Patients

Background

Cisplatin (cDDP) has regained interest for metastatic breast cancer (MBC) patients, given the platinum sensitivity in subtypes and better manageable toxicity. Here, the primary aim was to determine whether molecular characteristics of circulating tumor cells (CTCs) could identify patients responding to cDDP and to describe the outcomes to cDDP monotherapy in a large group of MBC patients pretreated with anthracycline- and taxane-based treatments.

Methods

Based on cell line data, a CTC-cDDP-sensitivity profile was generated. Applying an A’Herns single-stage phase II design, further investigation was considered worthwhile if 5/10 patients with a favorable profile responded to cDDP. Patients received 70mg/m² cDDP every three weeks, CTCs were enumerated and the CTC-cDDP-sensitivity profile was determined. In total, 65 heavily pretreated MBC patients (77% received ≥2 lines of previous chemotherapy for MBC) were eligible for the per-protocol analysis. Primary endpoint was response rate, secondary endpoints included best observed response, progression-free survival (PFS) and overall survival (OS).

Results

The best observed response during cDDP therapy was a partial response in 7% and stable disease in 56% of the patients. None of the patients with a favorable CTC-cDDP-sensitivity profile had a response. The median baseline CTC count was 8 (range 0-3254). Patients with <5 CTCs had a better PFS and OS than patients with ≥5 CTCs (median PFS 4.5 months (95%CI 2.38-6.62) vs. 2.1 months [(95%CI 1.34-2.80)(p=0.009)] and median OS 13.1 months (95%CI 9.89-16.33) vs. 5.6 months [(95%CI 3.60-7.64)(p=0.003)]. No other factors than CTC count were associated with outcome to cDDP therapy, including triple-negative breast cancer versus ER-positive tumors.

Conclusions

The CTC-cDDP-sensitivity profile was unable to select patients responding to cDDP monotherapy. In an unselected group of heavily pretreated MBC patients, cDDP yields outcomes comparable to other chemotherapeutic regimens for heavily pretreated MBC patients. CTC count was the only factor associated with outcome in these patients.

Clinical Trial Registration

(https://www.trialregister.nl/trial/3885, identifier NTR4046)

Protective Effect of Nanoceria on Cisplatin-Induced Nephrotoxicity by Amelioration of Oxidative Stress and Pro-inflammatory Mechanisms

Cisplatin (CP) is one of the most important anticancer compounds with its therapeutic usefulness in diverse types of solid cancer. However, its use is limited due to nephrotoxicity induced by it. Oxidative stress is an effective participant which contributes actively to pathogenesis of CP-induced nephrotoxicity. Nanoparticle form of a rare earth metal cerium, also known as nanoceria (NC), has come up as a potential antioxidant and anti-inflammatory agent. In the present study, administration of CP in Swiss mice resulted in reduction of body weight, increased oxidative stress and pro-inflammatory cytokine levels including IL-6 and TNF-α along with alteration in normal histological architecture of kidney. On the contrary, NC (0.2 and 2 mg/kg i.p.) ameliorated nephrotoxicity of CP which was evident by reduction in levels of renal injury markers in plasma, i.e., creatinine and blood urea nitrogen. NC ameliorated oxidative stress by showing a reduction in levels of malondialdehyde and increased levels of endogenous antioxidants reduced glutathione and catalase. Further, NC treatment also reduced the levels of pro-inflammatory cytokines. Furthermore, protective effect of NC was also corroborated by histopathological studies wherein, kidneys from CP group showed altered tissue structure after acute as well as chronic exposure of CP while the tissues from treated groups showed absence of alterations in kidney histology. The results from present study suggested that oxidative stress and pro-inflammatory cytokines play a central role in pathogenesis of CP-induced nephrotoxicity and NC provides protection from CP-induced nephrotoxicity due to its antioxidant and anti-inflammatory properties.

Platinum-based compounds for the treatment of metastatic breast cancer

The role of platinum-based compounds (PBCs) in the treatment of metastatic breast cancer (MBC) has been extensively studied. As single agents, high response rates have been observed in first-line therapy, while results in pretreated patients were discouraging. Regimens containing cisplatin/carboplatin together with taxanes showed the highest efficacy and safety as both first-line and second-line therapy. When administered with vinorelbine, the combination was also active and well tolerated in anthracycline- and taxane-pretreated patients. Combining PBCs with etoposide or nucleoside analogues showed moderate activity, yet high toxicity in the case of etoposide. The overall results for the combination with anthracyclines were disappointing. Addition of trastuzumab to PBC combinations showed remarkable activity and good tolerability in patients with HER2/neu overexpression. The use of cisplatin or carboplatin alongside novel targeted therapeutics for patients with triple-negative MBC seems promising and is being further evaluated. The use of PBCs against MBC requires careful patient selection and combination with the right chemotherapeutic agent.

Phase II study of a gemcitabine and cisplatin combination regimen in taxane resistant metastatic breast cancer

PURPOSE

To determine the safety and efficacy of gemcitabine and cisplatin in patients with taxane resistant metastatic breast cancer.

PATIENTS AND METHODS

Thirty-three taxane resistant metastatic breast cancer patients were treated with gemcitabine 1,250 mg/m2 IV infusion over 30 min on days 1 and 8, and with cisplatin 75 mg/m2 by IV infusion over 1 h on day 1 in 21 day cycles.

RESULTS

Of the 30 evaluable patients, there were 9 (30%) partial responses and no complete response, an overall objective response rate of 30%. Median time to progression and median survival duration for all study subjects were 7 (95% CI 5.1-8.9 months) and 15 months (95% CI 10.5-19.5 months), respectively. Toxicities included grade 3 and 4 leucopenia in 10 (30%), thrombocytopenia in 6 (18%), anemia in 2 (6%) and oral mucositis in 2 (6%). No grade 3 or 4 peripheral neuropathy, renal dysfunction, hepatic dysfunction, or nausea/vomiting was observed, and no treatment-related deaths occurred.

CONCLUSION

The described gemcitabine plus cisplatin combination was found to be an active and tolerable salvage regimen in patients with taxane resistant metastatic breast cancer.

Agents ameliorating or augmenting the nephrotoxicity of cisplatin and other platinum compounds: a review of some recent research

Cisplatin (cis-diamminedichloroplatinum (II)) is an effective agent against various solid tumours. Despite its effectiveness, the dose of cisplatin that can be administered is limited by its nephrotoxicity. Hundreds of platinum compounds (e.g. carboplatin, oxaliplatin, nedaplatin and the liposomal form lipoplatin) have been tested over the last two decades in order to improve the effectiveness and to lessen the toxicity of cisplatin. Several agents have been tested to see whether they could ameliorate or augment the nephrotoxicity of platinum drugs. This review summarizes these studies and the possible mechanisms of actions of these agents. The agents that have been shown to ameliorate experimental cisplatin nephrotoxicity include antioxidants (e.g. melatonin, vitamin E, selenium, and many others), modulators of nitric oxide (e.g. zinc histidine complex), agents interfering with metabolic pathways of cisplatin (e.g. procaine HCL), diuretics (e.g. furosemide and mannitol), and cytoprotective and antiapoptotic agents (e.g. amifostine and erythropoietin). Only few of these agents have been tested in humans. Those agents that have been shown to augment cisplatin nephrotoxicity include nitric oxide synthase inhibitors, spironolactone, gemcitabine and others. Combining these agents with cisplatin should be avoided.

Severe neurotoxicity, ototoxicity and nephrotoxicity following high-dose cisplatin and amifostine

Cisplatin in higher doses have been used routinely in the treatment of childhood tumours including neuroblastoma and germ cell tumors. Amifostine, a broad-spectrum cytoprotector of normal tissues, has been approved by U.S. Food and Drug Administration for use in patients receiving cisplatin. Such administration of amifostine has been reported to reduce cisplatin-related toxicities in some studies, but not all. The authors report a case of severe toxicity with cisplatin in a girl with epithelial cell carcinoma of the ovary despite the use of amifostine.

Otoproteção da amifostina aos efeitos ototóxicos da cisplatina: estudo em cobaias albinas por emissões otoacústicas produtos de distorção e microscopia eletrônica de varredura

A Cisplatina é uma potente droga antineoplásica, largamente utilizada para o tratamento do câncer, tanto em adultos quanto em crianças. Dentre seus efeitos colaterais, a ototoxicidade se apresenta como um dos mais importantes e leva à perda auditiva irreversível, bilateral, para as altas freqüências (4KHz -8KHz). Estudos têm tentado identificar drogas que, associadas à cisplatina, possam atuar como otoprotetores. Sabe-se que o mecanismo da ototoxicidade pela cisplatina está relacionado a alterações nos mecanismos antioxidantes das células ciliadas, principalmente as células ciliadas externas da cóclea. A amifostina tem conhecida ação antioxidante, com conhecido efeito otoprotetor aos efeitos lesivos da radioterapia. OBJETIVO: Nossa proposta foi avaliar através de emissões otoacústicas, por produtos de distorção (EOAPD) e por microscopia eletrônica de varredura (MEV), a existência de possível efeito otoprotetor da amifostina no tratamento com cisplatina. FORMA DE ESTUDO: Experimental. MATERIAL E MÉTODO: O estudo foi realizado em cobaias albinas, que foram divididas em três grupos: Grupo 1: 6 animais -12 orelhas - cisplatina 8,0 mg/Kg/dia (via intraperitoneal) por três dias; Grupo 2: 6 animais - 12 orelhas - amifostina 100 mg/Kg/ dia (via intraperitoneal) e 90 minutos após, cisplatina 8,0 mg/Kg/dia (via intraperitoneal) por três dias; Grupo 3: 03 animais - 06 orelhas - amifostina 100 mg/Kg/dia (via intraperitoneal) por três dias. RESULTADO: Encontramos EOAPD presentes e células ciliadas externas presentes, sem lesão anatômica a MEV, nos grupos 2 e 3. Concluímos que a amifostina, por sua ação antioxidante, atua como otoprotetor a ototoxicidade pela cisplatina. No entanto, seu uso não é recomendável nos casos de tumores potencialmente curáveis, por não se saber exatamente a influência da cisplatina na eficácia da quimioterapia.

Radioprotection by plant products: present status and future prospects

The development of radioprotective agents has been the subject of intense research in view of their potential for use within a radiation environment, such as space exploration, radiotherapy and even nuclear war. However, no ideal, safe synthetic radioprotectors are available to date, so the search for alternative sources, including plants, has been on going for several decades. In Ayurveda, the traditional Indian system of medicine, several plants have been used to treat free radical-mediated ailments and, therefore, it is logical to expect that such plants may also render some protection against radiation damage. A systematic screening approach can provide leads to identifying potential new candidate drugs from plant sources, for mitigation of radiation injury. This article reviews some of the most promising plants, and their bioactive principles, that are widely used in traditional systems of medicine, and which have rendered significant radioprotection in both in vitro and in vivo model systems. Plants and their constituents with pharmacological activities that may be relevant to amelioration of radiation-mediated damage, including antiemetic, antiinflammatory, antioxidant, cell proliferative, wound healing and haemopoietic stimulatories are also discussed.

Amifostine otoprotection to cisplatin ototoxicity: a guinea pig study using otoacoustic emission distortion products (DPOEA) and scanning electron microscopy

Cisplatin is an antineoplastic drug for cancer treatment in children and adults. The side effects of cisplatin ototoxicity are significant: irreversible bilateral hearing damage to high frequencies (4 kHz - 8 kHz). Reports recognize some drugs that are associated with cisplatin to obtain an otoprotector effect. The ototoxicity mechanisms of cisplatin are related to injury of hair cell oxidation mechanism, especially of outer hair cells. Aim: Using otoacoustic emissions distortion products (DPOEA) and scanning electron microscopy we intended to verify the action of amifostine, a radioprotective drug that has well known antioxidant characteristics and otoprotector effects to cisplatin injury. Study design: Experimental. Material and Method: We used an experimental guinea pig model. The study was performed as follows: group 1: 6 animals, 12 ears, cisplatin 8.0 mg/Kg/day (IP), 3 days. Group 2: 6 animals, 12 ears, amifostine 100 mg/Kg/day (IP) and after 90 minutes, cisplatin 8.0 mg/Kg/day (IP), 3 days and group 3: 3 animals, 6 ears, amifostine 100 mg/Kg/day (IP), 3 days. Results: DPOEA were present before and after treatment in groups 2 and 3. The normal cilium architecture of outer hair cells was supported in all cochlear turns in groups 2 and 3. We concluded that amifostine has a potential otoprotector effect against cisplatin ototoxicity and could be used in clinical trials.

High-Dose Cisplatin With Amifostine: Ototoxicity and Pharmacokinetics

OBJECTIVES/HYPOTHESIS

Ototoxicity is a common side effect of high-dose cisplatin treatment. Thiol-containing chemoprotectors ameliorate cisplatin ototoxicity under experimental conditions. The trial was initiated to test the efficacy of amifostine protection in high-dose cisplatin treatment (125-150 mg/m) for metastatic malignant melanoma, to correlate the ototoxic outcome with cisplatin pharmacokinetics, and to evaluate the importance of using a selective analytical method for the quantification of cisplatin.

STUDY DESIGN

Prospective study of 15 patients with stage IV malignant melanoma.

METHODS

Clinical follow-up of therapeutic response, pure-tone audiometry, and analysis of cisplatin and its monohydrated complex in blood ultrafiltrate by liquid chromatography with postcolumn derivatization were performed. Ultrafiltered blood platinum was analyzed by inductively coupled plasma mass spectrometry.

RESULTS

Ototoxicity and gastrointestinal toxicity were the most prominent side effects. Three patients ultimately required hearing aids. All patients had audiometric changes at one or more frequencies after the second treatment course, and all but one patient reported auditory symptoms. No correlation was found between hearing loss and blood cisplatin pharmacokinetics. Platinum levels determined by inductively coupled plasma mass spectrometry were higher than total platinum levels calculated from cisplatin and monohydrated complex concentrations obtained by liquid chromatography analysis.

CONCLUSION

Ototoxicity was unacceptable despite amifostine treatment. Cisplatin pharmacokinetics during the first treatment course were not predictive of hearing loss. Amifostine caused a lowering of dose-normalized area under the concentration-time curve for cisplatin and monohydrated complex. Use of the unselective inductively coupled plasma mass spectrometry analysis leads to an overestimation of active drug. Selective analysis of cisplatin is especially important when evaluating cisplatin pharmacokinetics during chemoprotector treatment.

Platinum-based chemotherapy in metastatic breast cancer: current status

Cisplatin and carboplatin are active in previously untreated patients with metastatic breast cancer (MBC) with mean response rates (RRs) of 50 and 32%, respectively. In pretreated patients the RR to cisplatin/carboplatin monotherapy declines markedly to <10%. Cisplatin and carboplatin have been combined with many other cytotoxics. In first-line setting high activity has been observed in combination with taxanes or vinorelbine (RRs consistently approximately 60%). It appears that these newer combinations are superior to older regimens with etoposide (RRs 30 to 50%) or 5-fluorouracil (RRs 40 to 60%). Cisplatin-/carboplatin-based regimens with infusional 5-FU and epirubicin/paclitaxel/vinorelbine achieve high RRs of around 60 to 80%. However these regimens are difficult to administer in all patients because they require central venous access for continuous 5-FU infusion. In pretreated MBC the combinations of cisplatin-taxane/vinorelbine/gemcitabine or carboplatin-docetaxel/vinorelbine yield RRs of 40 to 50%, which are higher than those achieved with platinum-etoposide/5-FU. In locally advanced disease cisplatin-based regimens achieve very high RRs (>80%). This would suggest that in chemotherapy-naïve patients platinum-based therapy might have an important role to play. Additionally the synergy demonstrated between platinum compounds, taxanes and herceptin, in preclinical and clinical studies is of immense importance and the results of the two ongoing Breast Cancer International Research Group randomized phase III studies are eagerly awaited. These studies may help clarify the role of platinum compounds in the treatment of metastatic and possibly early breast cancer.

Detailed gene copy number and RNA expression analysis of the 17q12-23 region in primary breast cancers

Chromosome region 17q12-23 commonly shows an increase in DNA copy number in breast cancers, suggesting that several oncogenes are located at this site. We performed a high-resolution expression array and comparative genomic hybridization analysis of genes mapped to the entire 17q12-23 region, to identify novel candidate oncogenes. We identified 24 genes that showed significant overexpression in breast cancers with gain of 17q12-23, compared to cancers without gain. These genes included previously identified oncogenes, together with several novel candidate oncogenes. FISH analysis using specific gene probes hybridized to tissue arrays confirmed the underlying amplification of overexpressed genes. This high-resolution analysis of the 17q12-23 region indicates that several established and novel candidate oncogenes, including a Wnt-signaling pathway member, are amplified and overexpressed within individual primary breast cancer samples. We were also able to confirm the presence of two apparently separate and reciprocally amplified groups of genes within this region. Investigation of these genes and their functional interactions will facilitate our understanding of breast oncogenesis and optimal management of this disease.

Influence of different radioprotective compounds on radiotolerance and cell cycle distribution of human progenitor cells of granulocytopoiesis in vitro

Ficoll-separated mononuclear cells (MNC) of cryopreserved human bone marrow were incubated with isotoxic doses of diltiazem, N-acetylcysteine (NAC), glycopolysaccharide extract of spirulina platensis (SPE), tempol, thiopental, WR2721 and WR1065. After irradiation with a single dose of 0.73 Gy, survival of granulocyte/macrophage colony-forming cells (GM-CFC) was determined at d 10-14, using an agar culture system. Diltiazem, NAC, tempol and WR1065 significantly improved radiotolerance with protection factors (PF) between 1.21 and 1.36 (n = 5, P < 0.05) at 0.73 Gy (PF-0.73 Gy). The survival curves of diltiazem (D0 = 0.88 Gy, n = 1.00), NAC (D0 = 0.92 Gy, n = 1.10), tempol (D0 = 0.99 Gy, n = 1.10), WR1065 (D0 = 0.89 Gy, n = 1.16) and control (D0 = 0.78 Gy, n = 1.00) over 0.36-2.91 Gy showed a significant radioprotective effect for D0 only for tempol (P = 0.018) and for the extrapolation number 'n' only in the case of NAC (P = 0.023). Cell cycle analysis of the CD34+ cell subpopulation (control-0 h: G1 = 82.7%, S = 13.7%, G2/M = 3.6%) revealed that all compounds with a significant PF-0.73 Gy also caused a significant increase in CD34+ cells in S phase up to 48 h. Within the first 24 h, only NAC (26.7 +/- 4.1%), tempol (14.3 +/- 1.0%) and possibly WR1065 (15.5 +/- 1.6%) had higher fractions of CD34+ S-phase cells compared with controls. This observation and the improvement of GM-CFC cloning efficiency indicated that only NAC was able to recruit progenitor cells in the cell cycle, whereas tempol and WR1065 possibly inhibited cell cycle progression by S and G2/M arrest. Of the radioprotectors tested, NAC, tempol and WR1065 may be suitable to support, alone or combined with cytokine therapy, accelerated haematopoietic recovery after irradiation.

Amifostine in clinical oncology: current use and future applications

Amifostine (Ethyol), an inorganic thiophosphate, is a selective broad-spectrum cytoprotector of normal tissues that provides cytoprotection against ionizing radiation and chemotherapeutic agents, thus preserving the efficacy of radiotherapy and chemotherapy. This review summarizes the preclinical data and clinical experience with amifostine, and provides insight into future clinical directions. Amifostine, an inactive pro-drug, is transformed to an active thiol after dephosphorylation by alkaline phosphatase found in the normal endothelium. The absence of alkaline phosphatase in the tumoral endothelium and stromal components, and the hypovascularity and acidity of the tumor environment, may explain its cytoprotective selectivity. The cytoprotective mechanism of amifostine is complicated, involving free radical scavenging, DNA protection and repair acceleration, and induction of cellular hypoxia. Intravenous administration of amifostine 740-900 mg/m(2) before chemotherapy and 250-350 mg/m(2) before each radiotherapy fraction are widely used regimens. The US Food and Drug Administration has approved the use of amifostine as a cytoprotector for cisplatin chemotherapy and for radiation-induced xerostomia. Ongoing trials are being conducted to determine the efficacy of amifostine in reducing radiation-induced mucositis and other toxicities. Novel schedules and routes of administration are under investigation, and may further simplify the use of amifostine and considerably broaden its applications.

A Phase II trial of cisplatin plus WR-2721 (amifostine) for metastatic breast carcinoma: an Eastern Cooperative Oncology Group Study (E8188)

BACKGROUND

Cisplatin has minimal antitumor activity when used as second- or third-line treatment of metastatic breast carcinoma. Older reports suggest an objective response rate of 8% when 60-120 mg/m2 of cisplatin is administered every 3-4 weeks. Although a dose-response effect has been observed with cisplatin, the dose-limiting toxicities associated with cisplatin (e.g., nephrotoxicity, ototoxicity, and neurotoxicity) have limited its use as a treatment for breast carcinoma. WR-2721 or amifostine initially was developed to protect military personnel in the event of nuclear war. Amifostine subsequently was shown to protect normal tissues from the toxic effects of alkylating agents and cisplatin without decreasing the antitumor effect of the chemotherapy. Early trials of cisplatin and amifostine also suggested that the incidence and severity of cisplatin-induced nephrotoxicity, ototoxicity, and neuropathy were reduced.

METHODS

A Phase II study of the combination of cisplatin plus amifostine was conducted in patients with progressive metastatic breast carcinoma who had received one, but not more than one, chemotherapy regimen for metastatic disease. Patients received amifostine, 910 mg/m2 intravenously over 15 minutes. After completion of the amifostine infusion, cisplatin 120 mg/m2 was administered over 30 minutes. Intravenous hydration and mannitol was administered before and after cisplatin. Treatment was administered every 3 weeks until disease progression.

RESULTS

Forty-four patients were enrolled in the study of which 7 (16%) were ineligible. A median of 2 cycles of therapy was administered to the 37 eligible patients. Six partial responses were observed for an overall response rate of 16%. Most patients (57%) stopped treatment because of disease progression. Neurologic toxicity was reported in 52% of patients. Seven different life-threatening toxicities were observed in patients while receiving treatment.

CONCLUSIONS

The combination of cisplatin and amifostine in this study resulted in an overall response rate of 16%. Neither a tumor-protective effect nor reduced toxicity to normal tissues was observed with the addition of amifostine to cisplatin in this trial.

Platinum compounds in the treatment of advanced breast cancer

Interest in platinum compounds for the treatment of breast cancer has been reawakened because of preclinical studies indicating synergy of platinum salts with the monoclonal antibody trastuzumab in human breast cancer cell lines that overexpress HER2/neu. Cisplatin, carboplatin, and iproplatin are not very active as single agents in patients with previously treated metastatic breast cancer (MBC). The activity of oxaliplatin has not been adequately tested in refractory MBC. On the other hand, cisplatin is very active as first-line chemotherapy, with response rates (RR) of 50%; carboplatin appears to be moderately active in patients without prior chemotherapy (RR around 30%). The clinical effectiveness of the other platinum compounds (iproplatin, oxaliplatin, and others) has not yet been fully tested as first-line chemotherapy. Platinum compounds have been extensively tested in combination with other antitumoral agents. Cisplatin combinations have been employed as neoadjuvant chemotherapy in women with locally advanced breast cancer. These combinations are very active, although the precise contribution of cisplatin to the overall activity is not known. Combinations with cisplatin have been investigated, essentially, as salvage therapy for patients with previously treated MBC. The combinations of cisplatin with older pharmacological agents (5-fluorouracil, etoposide) have moderate activity, while the combinations of cisplatin with the newer agents (vinorelbine, paclitaxel, docetaxel, gemcitabine) appear to be more active. The combinations of carboplatin with the classical agents (5-fluorouracil, etoposide) are poorly active in previously treated MBC; however, the combination of carboplatin with the taxanes (docetaxel, paclitaxel) is more active. Of greatest interest is the synergy between the platinum derivatives and the monoclonal antibody trastuzumab demonstrated in vitro in breast cancer cell lines overexpressing HER2/neu. Currently, several combinations of platinum compounds (either cisplatin or carboplatin) with docetaxel and trastuzumab are under clinical testing in patients with MBC who overexpress HER2/neu. The preliminary results are very promising, and these combinations will soon be tested in the adjuvant setting. Cisplatin, carboplatin, and perhaps, oxaliplatin appear to have some antitumor activity in MBC and can be combined safely with other agents that are active in this disease. However, the precise role that platinum compounds play in the treatment of breast cancer remains to be defined.