Project description:Cyclins and cyclin-dependent kinases (CDKs) are hyperactivated in numerous human tumors. To identify means of interfering with cyclins/CDKs, we performed nine genome-wide screens for human microRNAs (miRNAs) directly regulating cell-cycle proteins. We uncovered a distinct class of miRNAs that target nearly all cyclins/CDKs, which are very effective in inhibiting cancer cell proliferation. By profiling the response of over 120 human cancer cell lines, we derived an expression-based algorithm that can predict the response of tumors to cell-cycle-targeting miRNAs. Using systemic administration of nanoparticle-formulated miRNAs, we inhibited tumor progression in seven mouse xenograft models, including three treatment-refractory patient-derived tumors, without affecting normal tissues. Our results highlight the utility of using cell-cycle-targeting miRNAs for treatment of refractory cancer types.
Project description:Cyclins and cyclin-dependent kinases (CDKs) are hyperactivated in nearly all human tumor types. To identify new approaches for interfering with cyclins/CDKs, we systematically searched for microRNAs (miRNAs) regulating these proteins. We uncovered a group of miRNAs that target nearly all cyclins and CDKs, and demonstrated that these miRNAs are very effective in shutting off cancer cell expansion. By profiling the response of over 120 human cancer cell lines representing 12 tumor types to these cell-cycle-targeting miRNAs, we identified miRNAs particularly effective against triple-negative breast cancers and KRAS-mutated cancers. We also derived expression-based algorithm that predicts response of primary tumors to cell-cycle-targeting miRNAs. Using systemic administration of nanoparticle-formulated miRNAs, we halted tumor progression in seven mouse xenograft models, including three highly aggressive and treatment-refractory patient-derived tumors, without affecting normal tissues. Our results highlight the utility of using cell-cycle-targeting miRNAs for treatment of refractory cancer types.
Project description:Cyclins and cyclin-dependent kinases (CDKs) are hyperactivated in nearly all human tumor types. To identify new approaches for interfering with cyclins/CDKs, we systematically searched for microRNAs (miRNAs) regulating these proteins. We uncovered a group of miRNAs that target nearly all cyclins and CDKs, and demonstrated that these miRNAs are very effective in shutting off cancer cell expansion. By profiling the response of over 120 human cancer cell lines representing 12 tumor types to these cell-cycle-targeting miRNAs, we identified miRNAs particularly effective against triple-negative breast cancers and KRAS-mutated cancers. We also derived expression-based algorithm that predicts response of primary tumors to cell-cycle-targeting miRNAs. Using systemic administration of nanoparticle-formulated miRNAs, we halted tumor progression in seven mouse xenograft models, including three highly aggressive and treatment-refractory patient-derived tumors, without affecting normal tissues. Our results highlight the utility of using cell-cycle-targeting miRNAs for treatment of refractory cancer types.
Project description:MicroRNAs (miRNAs) are evolutionarily conserved, small, regulatory RNAs that negatively regulate gene expression. Extensive research in the last decade has implicated miRNAs as master regulators of cellular processes with essential role in cancer initiation, progression, and metastasis, making them promising therapeutic tools for cancer management. In this article, we will briefly review the structure, biogenesis, functions, and mechanism of action of these miRNAs, followed by a detailed analysis of the therapeutic potential of these miRNAs. We will focus on the strategies presently used for miRNA therapy; discuss their use and drawbacks; and the challenges and future directions for the development of miRNA-based therapy for human cancers.
Project description:MicroRNAs (miRNAs) have been known to affect various biological processes by repressing expression of specific genes. Here we describe an essential function of the miR-34/449 family during differentiation of epithelial cells. We found that miR-34/449 suppresses the cell-cycle machinery in vivo and promotes cell-cycle exit, thereby allowing epithelial cell differentiation. Constitutive ablation of all six members of this miRNA family causes derepression of multiple cell cycle-promoting proteins, thereby preventing epithelial cells from exiting the cell cycle and entering a quiescent state. As a result, formation of motile multicilia is strongly inhibited in several tissues such as the respiratory epithelium and the fallopian tube. Consequently, mice lacking miR-34/449 display infertility as well as severe chronic airway disease leading to postnatal death. These results demonstrate that miRNA-mediated repression of the cell cycle is required to allow epithelial cell differentiation.
Project description:MicroRNAs (miRNAs) are small noncoding RNAs that can function as either powerful tumor promoters or suppressors in numerous types of cancer. The ability of miRs to target multiple genes and biological signaling pathways has created intense interest in their potential clinical utility as predictive and diagnostic biomarkers, and as innovative therapeutic agents. Recently, accumulating preclinical studies have illustrated the feasibility of slowing tumor progression by either overexpressing tumor suppressive miRNAs, or by neutralizing the activities of oncogenic miRNAs in cell- and animal-based models of cancer. Here we highlight prominent miRNAs that may represent potential therapeutic targets in human malignancies, as well as review current technologies available for inactivating or restoring miRNA activity in clinical settings.