Colorectal cancer (CRC) is the third most common cancer and a leading cause of cancer-related death worldwide. About 1.8 million new cases were reported in 2018.Accordingly, there is an urgent need for development of effective strategies to lower the mortality and morbidity originated from this malignancy. MicroRNAs (miRNAs) play key roles in several cellular events. They have attracted a great deal of attention in the etiology of a variety of disorders including cancer and might be considered as disease biomarkers or treatment targets. Initiation and development of CRC is a multistep process that is caused by loss of function (LOF) or gain of function (GOF) in genes of different signaling pathways. Particular miRNAs conduct oncogenic impacts by suppressing their target transcripts and simulate the effects of LOF or GOF, whereas there may be no sign of common genetic or epigenetic modifications. On the contrary, some miRNAs serve as tumor suppressor and help to maintain normal functioning and cellular homeostasis. Hence, highlighting the function of each individual miRNA in CRC tumorigenesis could assign it as a therapeutic target or molecular marker for further investigations. In the present review, we have tried to compile the latest information regarding the dysregulated miRNAs in CRC and their function in different disease stages and signaling pathways involved.

Background: Non-small-cell lung cancer (NSCLC) is currently the leading cause of mortality cancer. Introducing noninvasive approaches to diagnose NSCLC, especially at an early phase, might improve the disease's prognosis. Long noncoding RNAs (lncRNAs), which are important regulators of the expression genes inside the cells, have been linked to a range of biological processes, such as cancer progression and metastasis, including NSCLC. The present work aims to determine the potential involvement of SIK-1-LNC and SIK-1 in NSCLC pathogenesis and the possible use of these molecules as novel biomarkers or therapeutic targets. Methods: In this work, the expression levels of SIK-1-LNC and SIK-1 in 50 pairs of NSCLC tumor and tumor marginal tissues were evaluated. So, after total RNA extraction and complementary DNA synthesis, the SIK-1-LNC and SIK-1 expression levels were evaluated by realtime PCR. In the study groups, clinical and pathological characteristics of the NSCLC patients were also examined. Results: Our findings showed that tumor samples had much lower levels of SIK-1 and SIK-1-LNC expression than tumor margin samples. SIK-1-LNC expression was correlated with SIK-1 levels in NSCLC samples. Interestingly, both stage and lymph node metastasis features of the tumor were associated significantly with SIK-1 and SIK-1-LNC expression levels. A ROC curve analysis indicated a biomarker index of 0.69 and 0.74 for SIK-1 and SIK-1-LNC, respectively. Conclusion: Collectively, our study emphasized the role of SIK-1-LNC and SIK-1 downregulation in NSCLC oncogenesis. Additionally, SIK-1 and SIK-1-LNC, particularly the latter, have shown remarkable potential to be utilized as new NSCLC biomarkers and therapeutic targets.