Targeting polyIC to EGFR over-expressing cells using a dsRNA binding protein domain tethered to EGF

Comparative Transcriptomic Analyses Revealed the Effects of Poly (I:C) on the Liver and Spleen of Argyrosomus japonicus

Poly (I:C) can work as an immunostimulant and a viral vaccine; however, its functional mechanism in aquatic animals needs to be further investigated. In this study, comparative transcriptomic analyses were performed to investigate the effects of poly (I:C) on Argyrosomus japonicus at 12 h and 48 h postinjection. A total of 194 and 294 differentially expressed genes were obtained in the liver and spleen, respectively. At 12 h, poly (I:C) injection could significantly influence the function of the metabolism-related pathways and immune-related pathways in the liver through the upregulation of the genes GST, LPIN, FOXO1, CYP24A1, ECM1, and SGK1, and the downregulation of the genes IL-1β, CXC19, TNFAIP3, and IRF1. At 48 h, poly (I:C) could enhance the liver energy metabolism by upregulating the genes TXNRD and ECM1, while it also induced some injury in the cells with the downregulation of the genes HBA and CYP24A1. In the spleen, poly (I:C) could regulate the fish immunity and inflammatory response by upregulating the genes DDIT4, C3, EFNA, and MNK, and by downregulating the genes ABCA1, SORT1, TNF, TLR2, IL8, and MHCII at 12 h, and at 48 h, the poly (I:C) had a similar influence as that in the liver. Intersection analyses demonstrated that CYP24A1 and ECM1 were the main functional genes that contributed to the health of the liver. Ten and four genes participated in maintaining the health of the two tissues after 12 h and 48 h, respectively. In summary, our results provided a new insight into ploy (I:C) application in A. japonicus, and it also helped us to better understand the fish response mechanism to the viral vaccine injection.

Protein purification strategies must consider downstream applications and individual biological characteristics

BACKGROUND

Proteins are used as reagents in a broad range of scientific fields. The reliability and reproducibility of experimental data will largely depend on the quality of the (recombinant) proteins and, consequently, these should undergo thorough structural and functional controls. Depending on the downstream application and the biochemical characteristics of the protein, different sets of specific features will need to be checked.

RESULTS

A number of examples, representative of recurrent issues and previously published strategies, has been reported that illustrate real cases of recombinant protein production in which careful strategy design at the start of the project combined with quality controls throughout the production process was imperative to obtain high-quality samples compatible with the planned downstream applications. Some proteins possess intrinsic properties (e.g., prone to aggregation, rich in cysteines, or a high affinity for nucleic acids) that require certain precautions during the expression and purification process. For other proteins, the downstream application might demand specific conditions, such as for proteins intended for animal use that need to be endotoxin-free.

CONCLUSIONS

This review has been designed to act as a practical reference list for researchers who wish to produce and evaluate recombinant proteins with certain specific requirements or that need particular care for their preparation and storage.

Hsa_circ_0076305 induces migration-proliferation dichotomy in gastric cancer

Recent studies have demonstrated that circular RNAs (circRNAs) play an important role in the development of gastric cancer (GC). The present study aimed to investigate the role of hsa_circ_0076305 (circPGC) in GC. The levels of circRNAs and mRNAs in AGS cell lines were detected via reverse transcription-quantitative PCR, and western blotting was performed to detect protein expression levels. Functional studies were explored by CCK8 assay and cell migration assay. Functional studies have indicated that circPGC orchestrates two cellular processes; it inhibits proliferation, and promotes migration and invasion in the GC AGS cell line, a phenomenon called ‘migration-proliferation dichotomy’, as well as epithelial-to-mesenchymal transition in AGS cells. In addition, circPGC degrades the extracellular matrix and basement membrane through matrix metallopeptidase (MMP)9 and MMP14, providing a microenvironment that facilitates cell migration. The results also demonstrated that circPGC expression is lower in clinical patients with later stages of GC, which is associated with poor prognosis. Taken together, these results suggest that circPGC exhibits migration-proliferation dichotomy during GC development, invasion and migration.

My journey from tyrosine phosphorylation inhibitors to targeted immune therapy as strategies to combat cancer

Since the 1980s there has been a drive toward personalized targeted therapy for cancer. "Targeted cancer therapy" originally focused on inhibiting essential tumor survival factors, primarily protein tyrosine kinases. The complexity and rapid mutability of tumors, however, enable them to develop resistance to tyrosine kinase inhibitors (TKIs), even when these are multitargeted or applied in combination. This has led to the development of targeted cancer immunotherapy, to enhance immune surveillance against the tumor. In this paper, we provide a personal view of the development of targeted therapy, from TKIs to targeted immunotherapy.

Epidermal growth factor receptor: Structure-function informing the design of anticancer therapeutics

Research on the epidermal growth factor (EGF) family and the family of receptors (EGFR) has progressed rapidly in recent times. New crystal structures of the ectodomains with different ligands, the activation of the kinase domain through oligomerisation and the use of fluorescence techniques have revealed profound conformational changes on ligand binding. The control of cell signaling from the EGFR-family is complex, with heterodimerisation, ligand affinity and signaling cross-talk influencing cellular outcomes. Analysis of tissue homeostasis indicates that the control of pro-ligand processing is likely to be as important as receptor activation events. Several members of the EGFR-family are overexpressed and/or mutated in cancer cells. The perturbation of EGFR-family signaling drives the malignant phenotype of many cancers and both inhibitors and antagonists of signaling from these receptors have already produced therapeutic benefits for patients. The design of affibodies, antibodies, small molecule inhibitors and even immunotherapeutic drugs targeting the EGFR-family has yielded promising new approaches to improving outcomes for cancer patients. In this review, we describe recent discoveries which have increased our understanding of the structure and dynamics of signaling from the EGFR-family, the roles of ligand processing and receptor cross-talk. We discuss the relevance of these studies to the development of strategies for designing more effective targeted treatments for cancer patients.

PSMA-homing dsRNA chimeric protein vector kills prostate cancer cells and activates anti-tumor bystander responses

The treatment of metastatic androgen-resistant prostate cancer remains a challenge. We describe a protein vector that selectively delivers synthetic dsRNA, polyinosinic/polycytidylic acid (polyIC), to prostate tumors by targeting prostate specific membrane antigen (PSMA), which is overexpressed on the surface of prostate cancer cells.

The chimeric protein is built from the double stranded RNA (dsRNA) binding domain of PKR tethered to a single chain anti-PSMA antibody. When complexed with polyIC, the chimera demonstrates selective and efficient killing of prostate cancer cells. The treatment causes the targeted cancer cells to undergo apoptosis and to secrete toxic cytokines. In a bystander effect, these cytokines kill neighboring cancer cells that do not necessarily overexpress PSMA, and activate immune cells that enhance the killing effect. The strong effects of the targeted polyIC are demonstrated on both 2D cell cultures and 3D tumor spheroids.