MicroRNAs (miRNAs) are short (~22 nucleotides) non-coding RNAs that are often intricately integrated into the regulatory networks of various cellular processes and govern the cell fate decision making events associated with oncogenesis by regulating the gene expression through post-transcriptional modifications. miRNAs repress the target genes by either degrading the target mRNA or by inhibiting the process of translation. However, mathematical and computational modeling of miRNA-mediated target gene regulation in various cellular network motifs suggests that miRNAs play a much more complex role in cellular decision-making events. In this review, we give an overview of the quantitative insights obtained from such kind of mathematical modeling of miRNA mediated gene regulation by highlighting the various factors associated with miRNA regulation that are pivotal in diversifying the cell fate decisions related to oncogenesis. Intriguingly, recent experiments suggest that miRNAs can even upregulate the translation of the target protein under certain circumstances, which may lead to more complexities in miRNA-mediated gene regulations. We discussed possible avenues to explore such unusual biological observations related to miRNA’s that can be modeled to get a detailed understanding of the influence of miRNAs in the context of oncogenesis.