Validation of an AAS method for the determination of platinum in biological fluids from patients receiving the oral platinum derivative JM216

The combination of an innovative dry powder for inhalation and a standard cisplatin-based chemotherapy in view of therapeutic intensification against lung tumours

Cisplatin is one of the most commonly used chemotherapy in lung cancer despite its high nephrotoxicity leading to an administration only every 3-4 weeks. This study is the first report of a preclinical investigation of therapeutic intensification combining a cisplatin dry powder for inhalation (CIS-DPI) with an intravenous (iv) cisplatin-based treatment. CIS-DPI with 50% cisplatin content (CIS-DPI-50) was developed using lipid excipients through scalable processes (high-speed and high-pressure homogenization and spray-drying). CIS-DPI-50 showed good aerodynamic performance (fine particle fraction of ~ 55% and a mass median aerodynamic particle size of ~ 2 µm) and a seven-fold increase and decrease in C_max in the lungs and in plasma, respectively, in comparison with an iv cisplatin solution (CIS-iv) in healthy mice. Finally, the addition of CIS-DPI-50 to the standard cisplatin/paclitaxel iv doublet increased the response rate (67% vs 50%), decreased the tumour growth and prolonged the median survival (31 vs 21 days), compared to the iv doublet in the M109 lung carcinoma model tending to demonstrate a therapeutic intensification of cisplatin.

GSTM1, GSTT1 and GSTP1 Ile105Val polymorphisms in outcomes of head and neck squamous cell carcinoma patients treated with cisplatin chemoradiation

Cisplatin (CDDP) combined with radiotherapy (RT) is employed in head and neck squamous cell carcinoma (HNSCC) with variable toxicities and clinical response. Glutathione S-transferases (GSTs) participate in CDDP excretion from cells, and genes encoding GSTs, GSTM1, GSTT1and GSTP1, are polymorphic in humans. This prospective study aimed to evaluate the roles of GSTM1, GSTT1, and GSTP1 Ile105Val polymorphisms in outcomes of HNSCC patients treated with CDDP chemoradiation. Ninety patients were genotyped by multiplex PCR. Urinary CDDP measurements were performed by HPLC. Treatment side effects and response were analysed by conventional criteria. Patients with GSTT1 genes showed 7.23- and 5.37-fold higher likelihood of presenting vomiting and ototoxicity, lower glomerular filtration rate (GFR), and lower elimination of CDDP in urine relative to patients with deleted genes. Patients harbouring the GSTP1 IleVal or ValVal genotypes showed 4.28-fold higher likelihood of presenting grade 2 or 3 vomiting and lower GFR with treatment than those harbouring the IleIle genotype. In multivariate Cox analysis, patients with the GSTP1 105ValVal genotype had 3.87 more chance of presenting disease progression than those with the IleIle or IleVal genotype (p < 0.01). Our findings provide preliminary evidence that inherited abnormalities in CDDP metabolism, related to GSTT1 and GSTP1 Ile105Val polymorphisms, alter outcomes of HNSCC patients treated with CDDP and RT.

Adverse drug reactions and kinetics of cisplatin excretion in urine of patients undergoing cisplatin chemotherapy and radiotherapy for head and neck cancer: a prospective study

Background

Cisplatin is a high-potency anticancer agent; however, it causes significant adverse drug reactions (ADRs). Potential pharmacokinetic markers must be studied to predict or prevent cisplatin-induced ADRs and achieve better prognosis. This study was designed to investigate the relationship between ADRs and kinetics of cisplatin excretion in the urine of patients undergoing high-dose cisplatin chemotherapy and radiotherapy for head and neck cancer.

Methods

Outpatients with head and neck cancer received a first cycle of high-dose cisplatin chemotherapy (80–100 mg/m²) concurrent to radiotherapy. ADRs (haematological, renal, and gastrointestinal reactions) were classified based on severity by National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE, version 4, grade 0–4). The kinetics of cisplatin excretion in urine was evaluated by high-performance liquid chromatography over three time periods: 0–12, 12–24, and 24–48 h after the administration of cisplatin. Spearman Correlation test and regression analysis were performed to assess the relationship between ADRs and cisplatin excretion in the urine.

Results

In total, 59 patients with a mean age of 55.6 ± 9.4 years were analysed; most patients were male (86.4%), white (79.7%), and with pharyngeal tumours in advanced stages (66.1%). The most frequently observed ADRs were anaemia (81.4%), lymphopenia (78%), and nausea (64.4%); mostly grades 1 and 2 of toxicity. The mean cisplatin excretion was 70.3 ± 64.4, 7.3 ± 6.3, and 5 ± 4 μg/mg creatinine at 0–12, 12–24, and 24–48 h, respectively. Statistical analysis showed that the amount of cisplatin excreted did not influence the severity of ADRs.

Conclusions

The most frequent ADRs were anaemia, lymphopenia, and nausea. Grades 1 and 2 were the severities for most ADRs. The period over which the highest cisplatin excretion observed was 0–12 h after chemotherapy, and cisplatin excretion could not predict toxicity.

Graphical abstract

Comparison of different sample preparation methods for platinum determination in cultured cells by graphite furnace atomic absorption spectrometry

BACKGROUND

Platinum-based agents are widely used in chemotherapy against solid tumors and insufficient intracellular drug accumulation is one of the leading causes of platinum resistance which is associated with poor survival of tumor patients. Thus, the detection of intracellular platinum is pivotal for studies aiming to overcome platinum resistance. In the present study, we aimed to establish a reliable graphite furnace atomic absorption spectrometry (GFAAS)-based assay to quantify the intracellular platinum content for cultured cells.

METHODS

Several most commonly applied cell preparation methods, including 0.2% HNO3, 0.2% Triton X-100, concentrated nitric acid, RIPA combined with concentrated nitric acid and hydroxide, followed by GFAAS for platinum detection were compared in ovarian, cervical and liver cancer cell lines to obtain the optimal one, and parameters regarding linearity, accuracy, precision and sensitivity were evaluated. Influence of other metals on platinum detection and the storage conditions of samples were also determined.

RESULTS

The treatment of cells with 0.2% HNO3 was superior to other approaches with fewer platinum loss and better repeatability. The recovery rate and precision of this method were 97.3%-103.0% and 1.4%-3.8%, respectively. The average recoveries in the presence of other metals were 95.1%-103.1%. The detection limit was 13.23 ug/L. The recovery rate of platinum remained acceptable even in cell samples stored in -20 °C or -80 °C for two months.

DISCUSSION

After comparison, we found that 0.2% HNO3 was optimal for intracellular platinum quantification based on GFAAS, which presented values compatible with that of inductively-coupled plasma mass-spectrometry (ICP-MS), and this is partially attributed to the simplicity of this method. Moreover, the assay was proved to be accurate, sensitive, cost-effective and suitable for the research of platinum-based antitumor therapy.

ET AAS evaluation of the stability and pH-sensitivity of, pH-sensitive stealth liposomes containing cisplatin in mouse plasma

In this work, stability and the pH-sensitivity of pH-sensitive stealth liposomes containing cisplatin exposed to plasma medium and their subsequent responses to pH modifications were evaluated. A method to determine platin in mouse plasma by electrothermal atomic absorption spectroscopy (ET AAS) was developed and validated. At first, a comparative study of sample preparation treatments with basic, acidic, and acidic added with Triton X-100 as a modifier was done. The best treatment was obtained with HCl 3% (v/v). The ET AAS method with acid treatment presented linearity at a range of 10-160 ng Pt/mL. The limits of detection (LOD) was 3.1 ng/mL Pt for acid treatment, while the limit quantification (LOQ) was 10 ng/mL Pt. The acid treatment presented good repeatability (VC<15.0%) and recovery close to 100%. This treatment was chosen for subsequent studies due to its best value of repeatability, recovery, LOD and lowest cost. pH-sensitive stealth liposomes, containing cisplatin, demonstrated low stability and poor response to pH variation after plasma incubation. These findings suggest that further studies are needed to improve liposome formulation i.e., to reduce its size.

Determination of ruthenium originating from the investigational anti-cancer drug NAMI-A in human plasma ultrafiltrate, plasma, and urine by inductively coupled plasma mass spectrometry

We present a highly sensitive, rapid method for the determination of ruthenium originating from the investigational anti-cancer drug NAMI-A in human plasma ultrafiltrate, plasma, and urine. The method is based on the quantification of ruthenium by inductively coupled plasma mass spectrometry and allows quantification of 30 ng L(-1) ruthenium in plasma ultrafiltrate and urine, and 75 ng L(-1) ruthenium in human plasma, in 150 microL of matrix. The sample pretreatment procedure is straightforward and only involves dilution with appropriate diluents. The performance of the method, in terms of accuracy and precision, fulfilled the most recent FDA guidelines for bioanalytical method validation. Validated ranges of quantification were 30.0 to 1 x 10(4) ng L(-1) for ruthenium in plasma ultrafiltrate and urine and 75.0 to 1 x 10(4) ng L(-1) for ruthenium in plasma. The applicability of the method and its superiority to atomic-absorption spectrometry were demonstrated in two patients who were treated with intravenous NAMI-A in a phase I trial. The assay is now successfully used to support pharmacokinetic studies in cancer patients treated with NAMI-A.

Determination of trace platinum by supramolecular catalytic kinetic spectrofluorimetry of β–cyclodextrin–platinum–KBrO3–salicylaldehyde furfuralhydrazone

A supramolecular catalytic kinetic spectrofluorimetric method was developed for the determination of platinum(IV) and the possible mechanism of catalytic reaction was discussed. The method was based on the fluorescence-enhancing reaction of salicylaldehyde furfuralhydrazone (SAFH) with potassium bromate, which was catalysed by platinum(IV) in a water-ethanol medium. beta-Cyclodextrin (beta-CD) obviously sensitized the determination at pH 5.20 and 25 degrees C. Under optimum conditions, the beta-CD-platinum-KBrO3-SAFH supramolecular kinetic catalytic reaction system had excitation and emission maxima at 372 and 461 nm, respectively. The linear range of this method was 0.60-180 ng ml-1 with a relative standard deviation of 1.2%, and the detection limit was 0.18 ng ml-1. Investigation of the mechanism and the effects of interferences is presented. The proposed method was applied successfully to determine trace platinum(IV) in the chemotherapeutic drug cisplatin and serum from patients with satisfactory results.

Determination of oxaliplatin in human plasma and plasma ultrafiltrate by graphite-furnace atomic-absorption spectrometry

A method for sensitive determination of the anti-cancer agent oxaliplatin in human plasma and human plasma ultrafiltrate (pUF) is presented. The method is based on the quantification of platinum by graphite-furnace atomic-absorption spectrometry, with Zeeman correction and an atomisation temperature of 2,700 degrees C. Sample pretreatment involves dilution of the samples with a solution containing 0.15 mol L(-1) NaCl and 0.20 mol L(-1) HCl in water. Validation was performed in accordance with the most recent FDA guidelines for bioanalytical method validation. All results were within requirements. The validated ranges of quantification were 0.10-400 micromol L(-1) for human pUF and 0.50-400 micromol L(-1) for plasma. The assay is now successfully used to support pharmacokinetic studies of cancer patients treated with oxaliplatin.