Venanzi, F. M. | Search bioRxiv

bioRxiv2019

p62-DNA-encoding plasmid reverts tumor grade, changes tumor stroma, and enhances anticancer immunity

Previously, we reported that the administration of a p62/SQSTM1-encoding plasmid demonstrates high safety and clinical benefits for human cancer patients, having also suppressed tumor growth and metastasis in dogs and mouse models. Here we investigated the mechanistic aspects of these effects. In mammary tumors bearing-dogs, p62 plasmid i.m. injections reduced tumor volumes, and reverted tumor grade to less aggressive lesions in 5 out of 6 animals, with one carcinoma switching to benign adenoma. The treatment increased levels of alpha-SMA in stroma cells and collagen 3 in the extracellular matrix, both of which correlate with a good clinical prognosis. p62 treatment also increased the abundance of intratumoral T-cell. To test the role of adaptive immunity, we compared protective effects of the plasmid against B16 melanoma in wild type C57BL/6J mice and in the corresponding SCID strain lacking lymphocytes. The plasmid was only protective in the wild type strain. Also, p62 plasmid amplified anti-tumor effect of adoptive T-cell transfer from tumor-bearing animals to animals challenged with the same tumors. We conclude that the plasmid acts indirectly via re-modeling of the tumor microenvironment, making it more favorable for increased anti-cancer immunity. Thus, the p62-encoding plasmid might be a new adjuvant for cancer treatments.

cancer biology↗

bioRxiv2018

Computational Discovery of Evolutionary Conserved Enterovirus 71 RNA Secondary Structures

Viral RNAs store information in their sequence and structure. Little, however is known about the contribution of RNA structure to viral replication and evolution. We previously described RNA ISRAEU to computationally identify structured regions in viral RNA based on evolutionary conservation of predicted structures. Here, we apply RNA GUESS (Generator of Uniformly Evolved Secondary Structures) to better understand enterovirus 71, a highly pathogenic human picornavirus. RNA GUESS identified previously known evolutionarily conserved picornavirus RNA structures, and uniquely predicted RNA structures with significant structural conservation despite the lack of an obvious sequence conservation. One structure consists of a stretch of obligatorily unpaired nucleotides that can potentially interact with RNA-binding proteins and siRNAs. Another, forms a potential RNA switch that can form two alternative structures while the third and fourth constitute hairpin-like structures. These findings provide a launching point for physical and genetic studies regarding the function and structures of these RNA elements.

bioinformatics↗