Search

Recently, antibody-based therapeutic agents are becoming most leading biologics for treating many diseases, especially for cancer. However, large-scale application of antibody drugs is still hampered by high cost and complex technical process. Endogenous expression of proteins or antibodies can be achieved by applying in vitro transcription (IVT) technique to produce mRNA and then deliver into body, which supplies opportunity to avoid many disadvantages in antibody production as well as clinical applications. Here, we designed the IVT-mRNA encoding the Pembrolizumab, as a commercial anti-PD-1 monoclonal antibody (mAb). The in vitro functional properties and in vivo antitumor activities of the Pembrolizumab expressed from mRNA were both assessed. Maximized expression level of the Pembrolizumab from IVT-mRNA was achieved via optimizing the usage of signal peptide and molar ratio of heavy/light chain. Then the mRNA was further formulated by lipid nanoparticle (LNP), which enable efficient in vivo delivery and protect mRNA from degradation. Intravenously delivered the single dose of mRNA-LNPs in mice resulted in duration of serum Pembrolizumab level over 25 μg/mL more than 35 days. Pharmacokinetic study exhibited significantly enhanced drug exposure of mRNA-encoded mAbs compared with direct injection of Pembrolizumab at same dose. Chronic treatment of the tumor-bearing mice with LNP-encapsulated Pembrolizumab mRNA effectively downregulated the growth of intestinal tumors and improved the animal survival. In brief, our present research demonstrated that the application of LNP-encapsulated IVT-mRNA can change the human body into a protein drug manufacturing site to express full-size mAbs for treating cancer and hold potential to be a novel alternative to protein-based therapies.

Aims: To evaluate anti-tumour effects and mechanism of novel BF-30 derivative via cell-based assays and melanoma-bearing model mice. Main methods: BF-30 derivatives were designed by fusing heptapeptide-palmitic tags to native BF-30 via a protease-cleavable linker and prepared by F-moc solid-phase synthesis. Albumin binding affinity test and in vitro control-released assay were performed to screen these BF-30 derivatives and explore the mechanism of anti-tumour effects. The selected BF-30 derivative was further subjected to the preclinical efficacy study and chronic evaluation of anti-tumour effects melanoma-bearing model mice. Key findings: Twenty-one BF-30 derivatives, termed LBF-1 to LBF-21, were obtained with high purity and accurate molecular weight. Surface plasmon resonance (SPR) measurements, plasma stability test and in vitro control-released assay all showed that LBF-14 exerted better druggability compared with the others. Moreover, LBF-14 was proved to inhibit the proliferation of B16F10 melanoma cell by disrupting the cytoplasmic membrane and binding to genomic DNA to prevent transcription. Furthermore, half-life of intact LBF-14 and released BF-30 in rhesus monkeys were approximately 120.9 h and 136.4 h, respectively, after a single subcutaneous injection of 0.9 mg/kg LBF-14. In addition, chronic treatment of LBF-14 significantly suppressed melanoma growth and improved the survival rate of B16F10-bearing mice with the observed inhibition of 63.5% for 0.3mg/kg and 91.5% for 0.9 mg/kg. Furthermore, results of H&E staining prove that chronic treatment of LBF-30 effectively suppressed metastasis and invasion of B16F10 cells. Significance: LBF-14 holds potential to be developed as a promising once-weekly candidate for the treatment of malignant melanoma.

Objectives: This study investigated plasma exosomal miRNA-139-3p as a blood-based biomarker for the early diagnosis and metastasis monitoring of colorectal cancer (CRC). Patients and Methods: Exosome-rich fractions were isolated from the plasma of 80 CRC patients, and 23 controls using a kit method. We then used real-time polymerase chain reaction (RT-qPCR) to detect miR-139-3p levels in all subjects to evaluate expression levels and the predictive value of plasma exosomal miR-139-3p in CRC. We also collected clinicopathological data to explore correlations between abnormal miR-139-3p expression and clinicopathological parameters. Results: When compared with healthy controls, exosomal miR-139-3p expression levels in CRC patients were significantly down-regulated. Furthermore, these expression levels were lower in metastatic colorectal cancer (mCRC) and submucosal patients. Receiver operating characteristic (ROC) curve analysis showed that exosomal miR-139-3p levels were differentiated between CRC patients and healthy controls, as well as between non-metastatic and metastatic patients. Conclusion: Our findings show that decreased exosomal miR-139-3p expression levels in CRC patient plasma may act as a novel biomarker for the early diagnosis and metastasis monitoring in CRC.