mirna

Breast cancer is a complex disease and one of the main causes of cancer-related mortality in women worldwide. In case of approximately 15% of all breast cancers, three markers i.e. estrogen receptors (ER), progesterone receptors (PR) and human epidermal growth factor receptors-2 (HER2) are not expressed, and is commonly termed as triple-negative breast cancer (TNBC). Particularly, TNBC is associated with a higher percentage of breast cancer related mortality, which is often aggressive and most frequently found with a BRCA1 mutation or increased basal marker expression. However, due to the limitations of chemotherapy and radiation based treatment; the current challenge is to establish a new strategy of diagnosis and treatment of TNBC. The deregulation of a number of microRNAs (miRNAs) in breast cancer has been widely reported. Therefore, this review is directed towards enhancing our understanding of the involvement of various miRNAs in the pathology of TNBC, their upregulations and downregulations and the effects on various factors. From recent studies a number of miRNAs are found to be related with TNBC, which have great potential to be used as a biomarker to determine the disease prognosis and predict the fate of disease. Again miRNA can be targeted to be applied as a therapeutic to provide a great benefit to the patients of TNBC by finding a new, safe, and effective treatment strategy.

Biomarkers have been used in the diagnosis of disease and other conditions for many decades. There are diverse ranges of analytical targets, including metabolites, nucleic acids and proteins were used as a biomarker. Clinical diagnoses already rely heavily on these for patient disease classification, management, and informing treatment and care pathways. For that there is always a need of rapid and point of care test. However, until fairly recently, studies of biomarker efficacy in a clinical setting were mainly limited to single or dual use, and the landscape was complex, confused, and often inconsistent. Few candidates emerged from this somewhat clouded picture: C-reactive protein, procalcitonin (PCT) for sepsis, ADA for mycobacterium tuberculosis and a Circulating miRNAs serve as molecular markers for diverse physiological and pathological conditions.

Colon cancer (CC) screening is important for diagnosing early stage for malignancy and therefore potentially reduces mortality from this disease because the cancer could be cured at the early disease stage. Early detection is needed if accurate and cost effective diagnostic methods are available. Mortality from colon cancer is theoretically preventable through screening. The Current screening method, the immunological fecal occult blood test, FOBTi, lacks sensitivity and requires dietary restriction, which impedes compliance. Moreover colonoscopy is invasive and costly, which decreases compliance, and in certain cases could lead to mortality. Compared to the FOBT test, a noninvasive sensitive screen that does not require dietary restriction would be more convenient. Colonoscopy screening is recommended for colorectal cancer (CRC). Although it is a reliable screening method, colonoscopy is an invasive test, often accompanied by abdominal pain, has potential complications and has high cost, which have hampered its application worldwide. A screening approach that uses the relatively stable and nondegradable microRNA molecules when extracted from either the noninvasive human stool, or the semi-invasive blood samples by available commercial kits and manipulated thereafter, would be more preferable than a transcriptomic messenger (m)RNA-, a mutation DNA-, an epigenetic-or a proteomic-based test. That approach utilizes reverse transcriptase (RT), followed by a modified quantitative real-time polymerase chain reaction (qPCR). To compensate for exosomal miRNAs that would not be measured, a parallel test could be performed on stool or plasma’s total RNAs, and corrections for exosomal loss are made to obtain accurate results. Ultimately, a chip would be developed to facilitate diagnosis, as has been carried out for the quantification of genetically modified organisms (GMOs) in foods. The gold standard to which the miRNA test is compared to is colonoscopy. If laboratory performance criteria are met, a miRNA test in human stool or blood samples based on high throughput automated technologies and quantitative expression measurements currently employed in the diagnostic clinical laboratory, would eventually be advanced to the clinical setting, making a noticeable impact on the prevention of colon cancer.

Through the development of new analysis technologies, many issues regarding the approach to tumoral diseases have been elucidated. With analytical assays developed in the last years, various omics technologies have evolved in such a manner that the characteristics of tumor cells and products can be evaluated (assessed) in the bloodstream of cancer patients at different times. Ovarian Cancer (OC) is one of the most difficult to diagnose umors, with low survival rates due to the high heterogeneity of these diseases that are distinct in terms of etiology and molecular characteristics, but which simply share an anatomical appearance. Recent findings have indicated that several types of ovarian cancer classified into different histotypes are in fact derived from non-ovarian issues and share few molecular similarities. Within this context, ovarian cancer screening and diagnosis can be made through the evaluation of circulating tumor cells in peripheral blood using liquid biopsy technologies. Advances in the study of various molecules analyzed by liquid biopsy have shown that elucidation of intratumoural and intertumoural heterogeneity and spatial and temporal tumor evolution could be traced by serial blood tests rather than by histopathological analyses of tissue samples from a primary tumor. Therefore, evaluation of some molecules such as circulating tumor cells (CTC), circulating tumor DNA (ctDNA), circulating cell-free RNA (non-coding and mRNA, extracellular vesicles), tumor-educated platelets or different miRNAs using liquid biopsy could lead to improvement of patient management.