Pharmacokinetics study of calf thymus DNA in rats and beagle dogs with 3H-labeling and tracing method

Liquid biopsy on the horizon in immunotherapy of non-small cell lung cancer: current status, challenges, and perspectives

Non-small cell lung cancer (NSCLC) is one of the most threatening malignancies to human health and life. In most cases, patients with NSCLC are already at an advanced stage when they are diagnosed. In recent years, lung cancer has made great progress in precision therapy, but the efficacy of immunotherapy is unstable, and its response rate varies from patient to patient. Several biomarkers have been proposed to predict the outcomes of immunotherapy, such as programmed cell death-ligand 1 (PD-L1) expression and tumor mutational burden (TMB). Nevertheless, the detection assays are invasive and demanding on tumor tissue. To effectively predict the outcomes of immunotherapy, novel biomarkers are needed to improve the performance of conventional biomarkers. Liquid biopsy is to capture and detect circulating tumor cells (CTCs), circulating tumor DNA (ctDNA) and exosomes in body fluids, such as blood, saliva, urine, pleural fluid and cerebrospinal fluid as samples from patients, so as to make analysis and diagnosis of cancer and other diseases. The application of liquid biopsy provides a new possible solution, as it has several advantages such as non-invasive, real-time dynamic monitoring, and overcoming tumor heterogeneity. Liquid biopsy has shown predictive value in immunotherapy, significantly improving the precision treatment of lung cancer patients. Herein, we review the application of liquid biopsy in predicting the outcomes of immunotherapy in NSCLC patients, and discuss the challenges and future directions in this field.

Pharmacokinetic study of Strongylocentrotus nudus egg polysaccharide in rats and beagles using a 3H-labeling method

Strongylocentrotus nudus egg polysaccharide (SEP) extracted from sea urchins has potential anticancer activity. However, little is known about its pharmacokinetic properties. To investigate the pharmacokinetics of SEP, it was radiolabeled with tritium. Furthermore, a sensitive, selective, and rapid liquid scintillation counter (LSC) method for quantifying ³H-SEP in biological matrix was validated. The lower quantification limit of the method was 4 Bq. The relative standard deviations (RSDs) of the intra- and inter-day precision were <3.0% and <3.9%, respectively. ³H-SEP was successfully applied to investigate the pharmacokinetics of SEP after intravenous administration of 20, 40, and 80 mg/kg (40 μCi/kg) in rats and 5, 10, and 20 mg/kg (6 μCi/kg) in beagles. The AUC_(0-t) of SEP at three different doses was 487.81 ± 39.99 mg/L*h, 1,003.10 ± 95.94 mg/L*h, and 2,188.84 ± 137.73 mg/L*h in rats and 144.12 ± 3.78 mg/L*h, 322.62 ± 28.03 mg/L*h, and 754.17 ± 37.79 mg/L*h in beagles. The terminal elimination half-life (t_1/2) of SEP was longer in beagles (204.29 ± 139.34 h) than in rats (35.48 ± 6.04 h). The concentration of SEP in plasma declined rapidly in both rats and beagles. All the study results provide detailed pharmacokinetic profiles of SEP in two kinds of animals, which will be helpful for further development.

Development and Pharmacokinetics Study of Antifungal Peptide Nanoliposomes by Liquid Chromatography-tandem Mass Spectrometry

Background:

The therapeutic ability and application of antifungal peptide (APs) are limited by their physico-chemical and biological properties, the nano-liposomal encapsulation would improve the in vivo circulation and stability. </P><P> Objective: To develop a long-circulating liposomal delivery systems encapsulated APs-CGA-N12 with PEGylated lipids and cholesterol, and investigated through in vivo pharmacokinetics.

Methods:

The liposomes were prepared and characterized, a rapid and simple liquid chromatographytandem mass spectrometry (LC-MS/MS) assay was developed for the determination of antifungal peptide in vivo, the pharmacokinetic characteristics of APs liposomes were evaluated in rats.

Results:

Liposomes had a large, unilamellar structure, particle size and Zeta potential ranged from 160 to 185 nm and -0.55 to 1.1 mV, respectively. The results indicated that the plasma concentration of peptides in reference solutions rapidly declined after intravenous administration, whereas the liposomeencapsulated ones showed slower elimination. The AUC(0-∞) was increased by 3.0-fold in liposomes in comparison with standard solution (20 mg·kg-1), the half-life (T1/2) was 1.6- and 1.5-fold higher compared to the reference groups of 20 and 40 mg·kg-1, respectively.

Conclusion:

Therefore, it could be concluded that liposomal encapsulation effectively improved the bioavailability and pharmacokinetic property of antifungal peptides.