1,721,058 research outputs found
Breast cancer metastasis: a microRNA story
No full textMicroRNAs (miRNAs) are small noncoding RNAs with regulatory functions, which play an important role in breast cancer. Several studies have shown that miRNAs can act either as tumor suppressors or as oncogenes, and that measurement of miRNA expression in malignancies may have diagnostic and prognostic implications. This article highlights a series of three recent studies that prove the involvement of miRNAs in breast cancer metastases. The first proves that miR-10b indirectly activates the pro-metastatic gene RHOC by suppressing HOXD10, thus leading to tumor invasion and metastasis. The second proves that miR-373 and miR-520c can also promote tumor invasion and metastasis, at least in part by regulating the gene CD44. The third identifies miR-335, miR-206, and miR-126 as suppressors of breast cancer metastasis. Loss of miR-335 leads to the activation of SOX4 and TNC (encoding tenascin C), which are responsible for the acquisition of metastatic properties. Altogether, these remarkable findings are important for our understanding of malignant transformation in the breast and may have implications for the management of patients with advanced breast cancer. The use of miRNAs as anticancer therapeutic agents is promising, and such fine molecular studies certainly help in bringing miRNAs closer to clinical practice
Chromosomal rearrangements and microRNAs: A new cancer link with clinical implications
No full textThere is widespread aberrant expression of mature and/or precursor microRNAs in cancer cells, as microRNAs are deregulated consequent to chromosomal alterations and other genomic abnormalities. The identification of such abnormalities has a clear diagnostic and prognostic significance, and there are ever increasing examples of links between certain human cancers and modifications at microRNA loci
microRNAs and cancer – new paradigms in molecular oncology
No full textThe “classic” view of molecular oncology indicates that cancer is a genetic disease involving tumor suppressor and oncogenic proteins. However, in the recent years, it has been demonstrated that small regulatory non-coding RNAs (ncRNAs) named microRNAs (miRNAs) are involved in human tumorigenesis, thus revealing a new layer in the molecular architecture of human cancer. Gene expression studies revealed that hundreds of miRNAs are deregulated in cancer cells and functional studies clarified that miRNAs are involved in all the molecular and biological processes that drive tumorigenesis. Here, we summarize the recent advances in miRNA involvement in human cancer and illustrate the benefits of using these knowledge for medical practice. New diagnostic classifiers based on miRNAs will soon be available for medical practitioners and, even more importantly, miRNAs may become novel anti-cancer tools
miRNAs, cancer, and stem cell division
No full textMicroRNAs (miRNAs) are known to regulate the expression of genes involved in the control of development, proliferation, apoptosis, and the stress response. As a cluster of recent Nature papers now show, altered expression of specific miRNA genes contributes to the initiation and progression of cancer
Involvement of MicroRNAs in Human Cancer: Discovery and Expression Profiling
No full textThe expression of microRNAs (miRNAs) is deregulated in human cancer, with some miRNAs consistently up- or down-regulated in more than one type of neoplasm. The demonstration that aberrantly expressed miRNAs can affect the function of known oncogenes and tumor suppressor genes established molecular links with pathways implicated in malignant transformation. Cell cycle progression, loss of differentiation, increased survival, invasion, and metastasis were shown to be all under the influence of miRNAs, thereby implicating that miRNAs can themselves act as oncogenes or tumor suppressor genes. Besides increasing our knowledge on the molecular basis of cancer, accumulating evidences indicate that miRNA expression profiling has the potential of being translated into clinical applications. Analysis of cancer tissues revealed that miRNAs could be molecular markers useful for cancer classification, prognostic stratification, and drug-response prediction. MiRNAs also emerged as circulating markers, which may become valuable for early diagnosis and follow-up investigations. If we consider that studies on miRNAs in cancer therapy have already produced important results, in just few years, miRNAs have had a great impact in all cancer areas. Whether this will translate into important clinical applications is still too early to say
Principles of MicroRNA Involvement in Breast Cancer
No full textEditorial on the role of microRNAs in breast cancer
Genetic chaos and antichaos in human cancers
No full textCancer is considered the genetic disease with the most complex pathogenetic mechanism. Contrary to normal human tissues, which function in a highly ordered and uniform manner, tumor tissues were considered to develop chaos. Here we propose that analysis of human neoplasia according to the concepts of chaos and antichaos allowed to distinguish two main types of cancers: the hematopoietic cancers, characterized by the orderly antichaos and solid cancers governed by a disordered complex of genetic and molecular events characteristic of a chaotic pattern. Genetic chaos and antichaos have generated rules that can be applied to the diagnosis and therapy of human tumors
MicroRNA e cancro
No full textI microRNA (miRNA o miR) sono piccoli RNA di circa 20-22 nucleotidi che regolano a livello post-trascrizionale l’espressione di numerosi RNA messaggeri con cui presentano complementarietà di sequenza. Nell’uomo, sono stati riconosciuti oltre 300 miRNA, che svolgono importanti funzioni fisiologiche. La deregolazione dell’espressione dei miRNA è stata dimostrata in cellule neoplastiche. Il coinvolgimento dei miRNA nella tumorigenesi umana è supportata dalla scoperta del loro ruolo nella regolazione di oncogeni e dalla scoperta di specifici profili di espressione associati a caratteristiche di significato prognostico. Lo studio dei miRNA ha così aperto nuove prospettive nella comprensione dello sviluppo delle cellule cancerose, permettendo di meglio comprendere la patogenesi tumorale, di migliorare le prospettive prognostiche e di aprire nuove possibilità terapeutiche
Regulation of microRNA expression: the hypoxic component
No full textmicroRNAs are involved in a wide variety of normal and pathological cellular processes, including tumorigenic transformation. Despite significant progress made towards understanding their mechanisms of action, much less is known about the regulation of expression of specific microRNAs. Recent reports have established a link between hypoxia, a key feature of the tumor microenvironment, and a group of microRNAs. Select members of this group seem to affect apoptotic signaling in a hypoxic environment and are also predicted to target genes of critical importance for tumor biology. Interestingly, most hypoxia-induced microRNAs are also overexpressed in human cancers, suggesting a role in tumorigenesis. We hereby discuss the known and predicted regulators of microRNA expression and approaches for expanding this fledgling research area
- …
