miRNAs are short, single-stranded, naturally occurring RNAs of 20-25 nucleotides in length. miRNAs are classified as ncRNAs (non-coding RNAs), which, unlike many other RNAs, have functions without being translated into proteins. Recent studies have shown that miRNAs play an important role in many biological processes, such as immune response, cell cycle regulation, metabolism, viral replication, stem cell differentiation, human development, and growth. and growth. It has been reported that in some cancers, miRNAs are not regulated properly, leading to cancerous growth, and in fact, miRNA expression and function are highly altered in many diseases, including cancer and fibrosis.
■What is miRNA?
PURMX Therapeutics believes that targeting pathways involved in human diseases with RNA-targeting oligonucleotides may be a novel and powerful therapeutic approach for many diseases, including cancer. This is based on new findings by Professor Hidetoshi Tahara and his laboratory at the Department of Cell and Molecular Biology, Faculty of Pharmaceutical Sciences, Hiroshima University, that miRNAs designed to target mRNA regulation of protein expression can act as gene regulators and control the expression of important genes.
■miRNA medicine
Based on this knowledge, PURMX Therapeutics has initiated the research and development of novel oligonucleotide therapeutics designed to replenish failing miRNAs in several cancers for which there are no effective treatments and where unmet medical needs remain. We are currently developing our first candidate, MIRX002, with a particular focus on malignant pleural mesothelioma and postoperative recurrent head and neck cancer, two cancers in which miRNAs are implicated in growth.
Technology
Platform
Our approach
PURMX is focusing its research and development efforts on miRNAs as a novel modality that can simultaneously suppress multiple pathways by which cancer grows.
Nucleic acid medicine is a modality that is not restricted by the structure of proteins, such as conventional small molecules and antibody drugs, and is attracting attention as a next-generation therapeutic drug with the potential to be applied to all genes.
The miRNA (MIRX002/miR-3140-3p) currently in clinical development by PURMX Therapeutics was discovered by phenotypic analysis of functional RNAs, including miRNAs, using a small RNA screening platform and cellular senescence as an indicator. This miRNA induces cell senescence and cell death in many cancer cells.
Hiroshima University and PURMX Therapeutics have many functional RNAs that can be used for screening. The small RNA screening platform also has the potential to identify other new functional RNAs through phenotypic analysis beyond cellular senescence/cell death that precedes the current study.
We identify miRNAs that exhibit novel actions against cancer. We are also analyzing miRNA phenotypes that function in many biological processes, such as immune response, cell cycle regulation, metabolism, viral replication, stem cell differentiation, human development, and growth, to discover miRNAs that may be new therapeutic candidates for various diseases.