Despite advances in diagnosis and therapy, cancer is still the leading cause of death worldwide. Beside the genetic and environmental factors, epigenetic factors also contribute to the etiology of cancer. More recently, a new class of small non-coding RNAs called MicroRNAs (miRs or miRNAs) has been linked to several human diseases, including cancer. MicroRNAs are involved in eukaryotic gene regulation, either by translational inhibition or exonucleolytic mRNA decay, targeted through imperfect complementarity between the MicroRNA and the 3′- un-translated region (3′-UTR) of the mRNA. Considering the potential of micro- RNAs in targeting many of human mRNA, these classes of 19-25 oligonucleotides are involved in almost every biological process, including cell cycle regulation, cell growth, apoptosis, cell differentiation and stress response. Growing evidence suggests that MicroRNAs have a vital role in cancer biology and recent studies have confirmed the oncogenic or tumour suppression role of MicroRNA in cancer cells. It have been shown that MicroRNA expression can itself be regulated both through oncogenes or tumour suppressors. There is a probability that MicroRNA expression can be regulated both in in vitro and in vivo by developing synthetic pre-MicroRNA molecules or antiMicroRNA antisense oligodeoxyribonucleotides which show a promising prospect of a possible use in curing cancer.

RNA processing is essential factor for synthesis of functional and structural proteins in eukaryote cells. In eukaryote organisms it will be initiated with transcription of DNA in nucleolus and terminated to mRNA translation in cytoplasm, finally mRNA degraded. Protein synthesis followed as different steps, includes 5' capping, poly adenylating, processing and transferring from nucleolus to cytoplasm that all processing control and regulate MicroRNA are small molecules that could be inhibit the translation or degrade the mRNA. Due to the main biological role of RNA in regulation of protein synthesis, it is obvious that fungal pathogenesis is highly related to RNA. Interfrence RNAs (iRNA) are small double strand RNA in fungi that produced by fungal genome or during translation process and play a key role in RNA silencing. Mycovirus is small double strand RNA that led to phenotypic variation in fungi and has a critical role in fungal pathogenesis. The recent studies demonstrated the role of RNA in fungal infection treatment. In this review because of key role of various type of fungal RNA we will discuss our current understanding of the fungal RNA pathways and their functions as well as how RNA can be used as a tool in fungal research especially for immunotherapy of fungal infection.

Although more than 98% of the human genome is transcribed, most of these transcripts are not translated into proteins. Rather, they are considered as non-coding RNAs.MicroRNAs (miRNAs) are very short non-coding RNAs approximately 22 nucleotides in length which regulate many key processes of cells such as growth, proliferation, differentiation, cell cycle, apoptosis (programmed cell death) and metabolism. On the other hand, it is known that these small regulatory molecules are involved in many human diseases such as different cancers and cardiovascular disorders. Therefore, discovery and functional characterization of novel miRNAs is a prominent achievement. Low abundance and spatiotemporal expression of these mediator molecules make their discovery difficult by conventional methods. Therefore, bioinformatics software have been designed for the prediction of stem-loop structures capable of producing miRNA precursors in the human genome. On the other hand, there are several bioinformatics tools for prediction of miRNA target genes. Prediction of miRNA target genes helps to characterize the function of a miRNA. In this paper, we have reviewed some of the common efficient bioinformatics tools and experimental approaches used for prediction and identification of the miRNA genes and their target genes.

Despite the recent progress in diagnostic and therapeutic methods, there is still a high rate of cancer-related deaths in the world. Late diagnosis and drug resistance can be considered as the main reasons for the high mortality rate among cancer patients. Lack of appropriate non-invasive diagnostic methods in cancer patients is associated with late diagnosis. Therefore, investigation of the molecular mechanisms of tumorigenesis is required to suggest the non-invasive diagnostic tumor markers. MicroRNAs (miRNAs) are the key regulators of cell proliferation, apoptosis, differentiation, and migration. Hence, miRNA deregulation can be involved in tumor progression. This study aimed to investigate the role of miR-30e during tumor progression. It has been shown that miR-30e mainly has a tumor suppressor role via the regulation of PI3K/AKT signaling, ubiquitin-proteasome system, transcription factors, autophagy, and epithelial-mesenchymal transition. This review can be a valuable step toward the suggestion of miR-30e as a therapeutic target and non-invasive diagnostic marker in cancer patients.