MicroRNA-155 targets MAP3K10 and regulates osteosarcoma cell growth

Research Progress of Exosome-Loaded miRNA in Osteosarcoma

Currently, although the improvement of surgical techniques and the development of chemotherapy drugs have brought a certain degree of development to the treatment of osteosarcoma, the treatment of osteosarcoma has many shortcomings, and its treatment is limited. MiRNAs and exosomes can be used as diagnostic tools, and they play an important role in the occurrence and chemotherapy resistance of osteosarcoma. Therefore, providing a new method for the treatment of osteosarcoma is the key to solving this problem. To systematically summarize the research status of exoskeleton drug-loaded miRNA in osteosarcoma, we identified and evaluated 208 studies and found that exosome-carrying miRNA can be used as an index for the diagnosis and prognosis of osteosarcoma and share a certain relationship with chemosensitivity. In addition, exosomes can also be used as a carrier of genetic drugs able to regulate the progression of osteosarcoma. Based on the above findings, we propose suggestions for the future development of this field, aiming to bring new ideas for the early diagnosis and treatment of osteosarcoma.

Knockdown of circ-RAD23B inhibits non-small cell lung cancer progression via the miR-142-3p/MAP4K3 axis

Background

The development of non‐small cell lung cancer (NSCLC) is associated with the deregulation of circRNAs. The objective of this study was to investigate the effects of circ‐RAD23B in NSCLC.

Methods

Circ‐RAD23B expression, miR‐142‐3p and MAP4K3 was detected by qPCR. Cell proliferation was investigated by CCK‐8 assay and colony formation assay. Cell migration and invasion were assessed by transwell assay. Angiogenesis ability was assessed by tube formation assay. Cell cycle distribution and cell apoptosis were monitored by flow cytometry. The predicted binding relationship between miR‐142‐3p and circ‐RAD23B or MAP4K3 was verified by dual‐luciferase reporter assay. The protein level of MAP4K3 was detected by western blot. Animal models were established to determine the role of circ‐RAD23B in vivo.

Results

Circ‐RAD23B was shown to be upregulated in NSCLC tissues and cells. Knockdown of circ‐RAD23B inhibited proliferation, migration, invasion, angiogenesis and promoted cell cycle arrest and apoptosis in NSCLC cells, and circ‐RAD23B knockdown also impeded tumor growth in vivo. Circ‐RAD23B acted as miR‐142‐3p sponge to inhibit miR‐142‐3p expression and thus enrich the expression of MAP4K3, a target of miR‐142‐3p. Rescue experiments presented that miR‐142‐3p inhibition reversed the effects of circ‐RAD23B knockdown, and MAP4K3 overexpression abolished the effects of miR‐142‐3p restoration. In addition, we found that circ‐RAD23B knockdown led to decreased phosphorylation expression of ERK1/2, JNK and p38, three key groups of the MAPK signaling pathway.

Conclusions

Circ‐RAD23B knockdown inhibited NSCLC development by regulating the miR‐142‐3p/MAP4K3 axis, which might be associated with the inactivation of the MAPK signaling pathway.

miRNA signatures in childhood sarcomas and their clinical implications

Progresses in multimodal treatments have significantly improved the outcomes for childhood cancer. Nonetheless, for about one-third of patients with Ewing sarcoma, rhabdomyosarcoma, or osteosarcoma steady remission has remained intangible. Thus, new biomarkers to improve early diagnosis and the development of precision-targeted medicine remain imperative. Over the last decade, remarkable progress has been made in the basic understanding of miRNAs function and in interpreting the contribution of their dysregulation to cancer development and progression. On this basis, this review focuses on what has been learned about the pivotal roles of miRNAs in the regulation of key genes implicated in childhood sarcomas.

Expression and Role of MicroRNA-663b in Childhood Acute Lymphocytic Leukemia and its Mechanism

Recent studies have shown that microRNAs (miRNAs) play a key role in various malignant tumors. MiR-663b has been found to have important roles in several cancers, however, the role of miR-663b in T cell acute lymphocytic leukemia (T-ALL) remains unclear. Therefore, we speculated that miR-663b might also play a crucial role in the development and process of T-ALL. In the present study, we found that miR-663b was up-regulated in the blood of children with T-ALL and T-ALL cell lines. TargetScan and dual luciferase reporter assay results showed that CD99 was a direct target of miR-663b. In order to further study the biological function of miR-663b in the development of T-ALL and to clarify its potential molecular mechanism, we detected the changes in proliferation, apoptosis, migration, and invasion of T-ALL cell line Jurkat before and after miR-663b inhibitor transfection. We found that miR-663b inhibitor inhibited Jurkat cell proliferation and induced apoptosis. In addition, miR-663b inhibitor repressed Jurkat cell migration and invasion. All these effects of miR-663b inhibitor on Jurkat cells were eliminated by CD99-silencing. These results have provided a new theoretical basis and strategy for the diagnosis and treatment of T-ALL.

miR‑9 depletion suppresses the proliferation of osteosarcoma cells by targeting p16

Osteosarcoma (OS) is a common primary malignancy in adolescents and children. MicroRNAs (miRNAs or miRs) can regulate the progression of OS. Herein, we explored the target genes and effects of miR-9 in OS. Cell growth, colony formation and cell cycle were respectively examined using a cell counting kit-8 (CCK-8), crystal violet staining and flow cytometry. The target gene of miR-9 was predicted according to the MicroRNA.org website. Luciferase activity was examined using a dual luciferase reporter gene assay kit. The corresponding factors levels were analyzed by carrying out reverse transcription-quantitative PCR (RT-qPCR) and western blot analysis. A mouse model of OS was also established and the volume and weight of the tumors of the mice with OS were measured. The levels of p16 in the mice with OS were detected by immunohistochemistry (IHC). The data revealed a high expression of miR-9 and a low expression of p16 in the OS tissue. p16 was found to be the target gene for miR-9 in OS. miR-9 depletion decreased the proliferation and colony formation of Saos-2 cells by arresting the cells at the G1 phase, accompanied by the downregulation of cyclin A, cyclin D1 and c-Myc expression levels. Moreover, miR-9 depletion inhibited the phosphorylation of p38, c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK). In vivo, miR-9 depletion decreased the tumor volume and weight and increased p16 expression in the mouse tumor tissues. Nevertheless, p16 silencing reversed the suppressive effects of miR-9 inhibitors on OS cells. On the whole, the findings of this study substantiate that miR-9 depletion suppresses cell proliferation by targeting p16 in OS and by mediating the activation of the ERK/p38/JNK pathway.