E3 ubiquitin ligase isolated by differential display regulates cervical cancer growth in vitro and in vivo via microRNA-143

MiRNAs as Novel Adipokines: Obesity-Related Circulating MiRNAs Influence Chemosensitivity in Cancer Patients

Adipose tissue is an endocrine organ, capable of regulating distant physiological processes in other tissues via the release of adipokines into the bloodstream. Recently, circulating adipose-derived microRNAs (miRNAs) have been proposed as a novel class of adipokine, due to their capacity to regulate gene expression in tissues other than fat. Circulating levels of adipokines are known to be altered in obese individuals compared with typical weight individuals and are linked to poorer health outcomes. For example, obese individuals are known to be more prone to the development of some cancers, and less likely to achieve event-free survival following chemotherapy. The purpose of this review was twofold; first to identify circulating miRNAs which are reproducibly altered in obesity, and secondly to identify mechanisms by which these obesity-linked miRNAs might influence the sensitivity of tumors to treatment. We identified 8 candidate circulating miRNAs with altered levels in obese individuals (6 increased, 2 decreased). A second literature review was then performed to investigate if these candidates might have a role in mediating resistance to cancer treatment. All of the circulating miRNAs identified were capable of mediating responses to cancer treatment at the cellular level, and so this review provides novel insights which can be used by future studies which aim to improve obese patient outcomes.

MicroRNA‑143 increases cell apoptosis in myelodysplastic syndrome through the Fas/FasL pathway both in vitro and in vivo

Whilst the role of microRNA‑143 (miR‑143) in myelodysplastic syndrome (MDS) remains unclear, abnormally expressed microRNA‑143 has been detected in many types of cancer tissues. In this study, we describe a cohort study for the verification of miR‑143 expression, as well as the investigation of the molecular mechanisms of miR‑143 in MDS/acute myeloid leukaemia (AML). In a series of experiments, miR‑143 recombinant lentiviral vectors transformed into SKM‑1 cells were either overexpressed or knocked down, and the results illustrated that the overexpression of miR‑143 inhibited SKM‑1 cell growth, arrested the SKM‑1 cells in the G0/G1 phase, interfered with cell proliferation and induced cell apoptosis via the Fas/FasL pathway. Conversely, miR‑143 knockdown induced a decrease in the apoptosis and promoted the proliferation of SKM‑1 cells. Moreover, miR‑143 was shown to suppress MLLT3/AF9 expression by binding to its 3'‑UTR. Taken together, the findings of this study indicate that miR‑143 may be a critical regulator of MDS/AML cell carcinogenesis, acting as a potent antitumour molecular target for the diagnosis or treatment of cancers associated with the abnormal expression of MLLT3/AF9, hence facilitating the development of potential therapeutics against MDS/AML.

Novel Insights Into E3 Ubiquitin Ligase in Cancer Chemoresistance

Drug resistance can obstruct successful cancer chemotherapy. The ubiquitin-proteasome pathway has emerged as a crucial player that controls steady-state protein levels regulating multiple biological processes, such as cell cycle, cellular proliferation, apoptosis, and DNA damage response, which are involved in oncogenesis, cancer development, prognosis, and drug resistance. E3 ligases perform the final step in the ubiquitination cascade, and determine which protein becomes ubiquitylated by specifically binding the substrate protein. They are promising drug targets thanks to their ability to regulate protein stability and functions. Although patient survival has increased in recent years with the availability of novel agents, chemoresistance remains a major problem in cancer management. E3 ligases attract increasing attention with advances in chemoresistance knowledge. To explore the role of E3 ligase in cancer chemotherapy resistance and the underlying mechanism, we summarize the growing number of E3 ligases and their substrate proteins, which have emerged as crucial players in cancer chemoresistance and targeted therapies.