Akt3 activation by R-Ras in an endothelial cell enforces quiescence and barrier stability of neighboring endothelial cells via Jagged1

Communication between adjacent endothelial cells is important for the homeostasis of blood vessels. We show that quiescent endothelial cells use Jagged1 to instruct neighboring endothelial cells to assume a quiescent phenotype and secure the endothelial barrier. This phenotype enforcement by neighboring cells is operated by R-Ras through activation of Akt3, which results in upregulation of a Notch ligand Jagged1 and consequential upregulation of Notch target genes, such as UNC5B, and VE-cadherin accumulation in the neighboring cells. These signaling events lead to the stable interaction between neighboring endothelial cells to continue to fortify juxtacrine signaling via Jagged1-Notch. This mode of intercellular signaling provides a positive feedback regulation of endothelial cell-cell interactions and cellular quiescence required for the stabilization of the endothelium.

The antagonistic effect of FTO on METTL14 promotes AKT3 m6A demethylation and the progression of esophageal cancer

BACKGROUND

As the most abundant modification in eukaryotic messenger RNAs (mRNAs), N6-methyladenosine (m6A) plays vital roles in many biological processes.

METHODS

Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and transcriptomic RNA sequencing (RNA-seq) were used to screen for m6A targets in esophageal cancer cells and patients. The role of m6A RNA methylase in esophageal cancer was also analyzed using bioinformatics. In vitro and in vivo experiments were used to analyze gene expression and function. CCK-8, colony formation, cell apoptosis and immunofluorescence staining assays were performed to evaluate the proliferation, migration and invasion of esophageal cancer cells, respectively. Western blot analysis, RNA stability, RIP and luciferase reporter assays were performed to elucidate the underlying mechanism involved.

RESULTS

We found that the m6A demethylase FTO was significantly upregulated in esophageal cancer cell lines and patient tissues. In vivo and in vitro assays demonstrated that FTO was involved in the proliferation and apoptosis of esophageal cancer cells. Moreover, we found that the m6A methyltransferase METTL14 negatively regulates FTO function in esophageal cancer progression. FTO alone is not related to the prognosis of esophageal cancer, and its function is antagonized by METTL14. By using transcriptome-wide m6A-seq and RNA-seq assays, we revealed that AKT3 is a downstream target of FTO and acts in concert to regulate the tumorigenesis and metastasis of esophageal cancer. Taken together, these findings provide insight into m6A-mediated tumorigenesis in esophageal cancer and could lead to the design of new therapeutic strategies.

Megalencephaly secondary to a novel germline missense variant p.Asp322Tyr in AKT3 associated with growth hormone deficiency and central hypothyroidism: A case report

Germline gain of function variations in the AKT3 gene cause brain overgrowth syndrome with megalencephaly and diffuse bilateral cortical malformations. Here we report a child with megalencephaly, who is a carrier of a novel heterozygous missense variant in the AKT3 gene NM_005465.7:c.964G>T,p.Asp322Tyr. The phenotype of this patient is associated with pituitary deficiencies diagnosed at 2 years of age: growth hormone (GH) deficiency responsible for growth delay and central hypothyroidism. After 6 months of GH treatment, intracranial hypertension was noted, confirmed by the observation of papilledema and increased intracranial pressure, requiring the initiation of acetazolamide treatment and the discontinuation of GH treatment. This is the second reported patient described with megalencephaly and AKT3 gene variant associated with GH deficiency . Other endocrine disorders have also been reported in few cases with hypothyroidism and hypoglycemia. Pituitary deficiency may be a part of the of megalencephaly phenotype secondary to germline variant in the AKT3 gene. Special attention should be paid to growth in these patients and search for endocrine deficiency is necessary in case of growth retardation or hypoglycemia.

RUNX1 targeting AKT3 promotes alveolar hypercoagulation and fibrinolytic inhibition in LPS induced ARDS

BACKGROUND

Alveolar hypercoagulation and fibrinolytic inhibition are mainly responsible for massive alveolar fibrin deposition, which are closely related with refractory hypoxemia in acute respiratory distress syndrome (ARDS). Our previous study testified runt-related transcription factor (RUNX1) participated in the regulation of this pathophysiology in this syndrome, but the mechanism is unknown. We speculate that screening the downstream genes associated with RUNX1 will presumably help uncover the mechanism of RUNX1.

METHODS

Genes associated with RUNX1 were screened by CHIP-seq, among which the target gene was verified by Dual Luciferase experiment. Then the efficacy of the target gene on alveolar hypercoagulation and fibrinolytic inhibition in LPS-induced ARDS was explored in vivo as well as in vitro. Finally, whether the regulatory effects of RUNX1 on alveolar hypercoagulation and fibrinolytic in ARDS would be related with the screened target gene was also sufficiently explored.

RESULTS

Among these screened genes, AKT3 was verified to be the direct target gene of RUNX1. Results showed that AKT3 was highly expressed either in lung tissues of LPS-induced rat ARDS or in LPS-treated alveolar epithelia cell type II (AECII). Tissue factor (TF) and plasminogen activator inhibitor 1 (PAI-1) were increasingly expressed both in lung tissues of ARDS and in LPS-induced AECII, which were all significantly attenuated by down-regulation of AKT3. Inhibition of AKT3 gene obviously ameliorated the LPS-induced lung injury as well as the collagen I expression in ARDS. RUNX1 overexpression not only promoted the expressions of TF, PAI-1, but also boosted AKT3 expression in vitro. More importantly, the efficacy of RUNX1 on TF, PAI-1 were all effectively reversed by down-regulation of AKT3 gene.

CONCLUSION

AKT3 is an important target gene of RUNX1, through which RUNX1 exerted its regulatory role on alveolar hypercoagulation and fibrinolytic inhibition in LPS-induced ARDS. RUNX1/ATK3 signaling axis is expected to be a new target for the exploration of ARDS genesis and treatment.

The somatic p.T81dup variant in AKT3 gene underlies a mild cerebral phenotype and expands the spectrum including capillary malformation and lateralized overgrowth

Heterozygous germline or somatic variants in AKT3 gene can cause isolated malformations of cortical development (MCDs) such as focal cortical dysplasia, megalencephaly (MEG), Hemimegalencephaly (HME), dysplastic megalencephaly, and syndromic forms like megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome, and megalencephaly-capillary malformation syndrome. This report describes a new case of HME and capillary malformation caused by a somatic AKT3 variant that differs from the common p.E17K variant described in literature. The patient's skin biopsy from the angiomatous region revealed an heterozygous likely pathogenic variant AKT3:c.241_243dup, p.(T81dup) that may affect the binding domain and downstream pathways. Compared to previously reported cases with a common E17K mosaic variant, the phenotype is milder and patients showed segmental overgrowth, an uncommon characteristic in AKT3 variant cases. These findings suggest that the severity of the disease may be influenced not only by the level of mosaicism but also by the type of variant. This report expands the phenotypic spectrum associated with AKT3 variants and highlights the importance of genomic analysis in patients with capillary malformation and MCDs.

NXNL2 Promotes Colon Cancer Proliferation and Metastasis by Regulating AKT Pathway

This study aimed to explore the role of nucleoredoxin-like 2 (NXNL2) in colon cancer (CC). The GEPIA and UALCAN databases were analyzed to explore genes involved in the prognosis of CC patients. DLD1 cells were treated with the DNA methylation inhibitor 5-azacitidine to validate the above findings. The methyltransferase DNMT (DNA methylation) was further knocked down by shRNA, then the expression of NXNL2 was assessed by qPCR. The role of NXNL2 on cell proliferation and metastasis was examined using corresponding assays. NXNL2 was found to exhibit the greatest impact on the prognosis of CC patients. High NXNL2 correlated with poor survival outcomes of CC. The expression of NXNL2 was regulated by DNA methylation. NXNL2 promoted CC cell proliferation and metastasis. Also, NXNL2 promoted the AKT pathway activity. In conclusion, NXNL2 could affect the cancer cell proliferation and metastasis, and has a poor survival prognosis in CC.

The transcription factor TBP promotes hepatocellular carcinoma progression by activating AKT3

The present work was performed to clarify the role of TATA-binding protein (TBP) in hepatocellular carcinoma (HCC). TBP expression in adjacent liver tissues and HCC tissue sample was detected by immunohistochemistry and qRT-PCR. With CCK-8, BrdU, flow cytometry, and transwell assays, the malignancy of cancer cell lines were evaluated. The binding sites of TBP and AKT serine/threonine kinase 3 (Akt3) promoter region were predicted by PROMO database, and the binding relationship between TBP and AKT3 promoter was verified with dual luciferase reporter gene assay and ChIP-qPCR assay. The effect of TBP on AKT3 expression was examined by immunoblotting. The signaling pathways associated with AKT3 were predicted by gene set enrichment analysis (GSEA) with LinkedOmics database. It was revealed that, TBP expression in HCC tissues and cell lines was up-regulated, which was associated with the short survival time of patients. Up-regulation of TBP promoted the viability and aggressiveness of HCC cells, while knockdown of TBP had opposite effects. TBP could bind with AKT3 promoter region, and TBP overexpression promoted the expression of AKT3, while its knockdown worked oppositely. Additionally, TBP/AKT3 axis modulated mTOR expression in HCC cells. In conclusion, TBP promotes the transcription of AKT3, thus accelerating the malignant progression of HCC.

The Multifunctional Nature of the MicroRNA/AKT3 Regulatory Axis in Human Cancers

Serine/threonine kinase (AKT) signaling regulates diverse cellular processes and is one of the most important aberrant cell survival mechanisms associated with tumorigenesis, metastasis, and chemoresistance. Targeting AKT has become an effective therapeutic strategy for the treatment of many cancers. AKT3 (PKBγ), the least studied isoform of the AKT family, has emerged as a major contributor to malignancy. AKT3 is frequently overexpressed in human cancers, and many regulatory oncogenic or tumor suppressor small non-coding RNAs (ncRNAs), including microRNAs (miRNAs), have recently been identified to be involved in regulating AKT3 expression. Therefore, a better understanding of regulatory miRNA/AKT3 networks may reveal novel biomarkers for the diagnosis of patients with cancer and may provide invaluable information for developing more effective therapeutic strategies. The aim of this review was to summarize current research progress in the isoform-specific functions of AKT3 in human cancers and the roles of dysregulated miRNA/AKT3 in specific types of human cancers.

CircLRRFIP1 promotes the proliferation and differentiation of chicken skeletal muscle satellite cells by sponging the miR-15 family via activating AKT3-mTOR/p70S6K signaling pathway

Skeletal muscle is important for animal meat production, regulating movements, and maintaining homeostasis. Circular RNAs (circRNAs) have been founded to play vital role in myogenesis. However, the effects of the numerous circRNAs on growth and development of the skeletal muscle are yet to be uncovered. Herein, we identified circLRRFIP1, which is a novel circular RNA that is preferentially expressed in the skeletal muscle. To study the role of circLRRFIP1 in the skeletal muscle, the skeletal muscle satellite cells (SMSCs) was used to silenced or overexpressed circLRRFIP1. The results obtained in this study showed that circLRRFIP1 play a positive role in the proliferation and differentiation of SMSCs. The SMSCs were generated with stable knockdown and overexpression of circLRRFIP1, and the results showed that circLRRFIP1 exerts a stimulatory effect on the proliferation and differentiation of SMSCs. We further generated SMSCs with stable knockdown and overexpression of circLRRFIP1, and the results revealed that circLRRFIP1 exerts a stimulatory effect on the proliferation and differentiation of SMSCs. Mechanistically, circLRRFIP1 targets the myogenic inhibitory factor-miR-15 family to release the suppression of the miR-15 family to AKT3. The knockdown of AKT inhibits SMSC differentiation through the mTOR/p70S6K pathway. Taken together, the results obtained in this present study revealed the important role and the regulatory mechanisms of circLRRFIP1 in the development of chicken skeletal muscle. Therefore, this study provides an attractive target for molecular breeding to enhance meat production in the chicken industry.

Downregulation of circ_0024028 inhibits IL-22-induced keratinocyte proliferation and migration by miR-486-3p/AKT3 axis

Circular RNA (circRNA) has been confirmed to participate in psoriasis process, but the role of circ_0024028 in psoriasis development is still unclear. Interleukin 22 (IL-22)-induced keratinocytes (HaCaT) were used to construct psoriasis cell models in vitro. The expression of circ_0024028, microRNA (miR)-486-3p and AKT serine/threonine kinase 3 (AKT3) was analyzed by quantitative real-time PCR. Cell function was assessed by cell counting kit 8 assay, EdU assay, transwell assay, and wound healing assay. Protein expression was examined using western blot analysis. RNA interaction was confirmed by dual-luciferase reporter assay and RIP assay. Exosomes were isolated from cell culture medium using ultracentrifugation and examined by transmission electron microscopy and nanoparticle tracking analysis. Circ_0024028 was highly expressed in psoriasis lesions and IL-22-induced HaCaT cells, and its silencing could inhibit IL-22-induced HaCaT cell proliferation and migration. MiR-486-3p could be sponged by circ_0024028, and its inhibitor restored the functions of circ_0024028 knockdown on IL-22-induced HaCaT cell proliferation and migration. AKT3 was targeted by miR-486-3p, and its overexpression reversed the inhibitory effect of miR-486-3p on IL-22-induced HaCaT cell proliferation and migration. AKT3 expression was positively regulated by circ_0024028, and circ_0024028/miR-486-3p/AKT3 axis could regulate the activity of AKT/mTOR pathway. Additionally, exosomes mediated the transfer of circ_0024028 in cells. Circ_0024028 might be a potential target for psoriasis treatment, which knockdown repressed IL-22-induced keratinocytes proliferation and migration through miR-486-3p/AKT3 pathway.

Overexpression of miR-181a regulates the Warburg effect in triple-negative breast cancer

OBJECTIVE

Triple-negative breast cancer (TNBC) is highly aggressive and leads to a poor prognosis. microRNA-181a (miR-181a) exhibits strong antineoplastic effects in many types of cancer. In this study, we examine the responses of human miR-181a-transfected TNBC cells and explore the mechanisms underlying the observed effects.

METHODS

A series of cellular assays were conducted using cells from the MDA-MB-231 TNBC line to assess the impact of miR-181a overexpression. The extracellular acidification rate, lactate production and glucose uptake were evaluated as a measure of aerobic glycolysis (i.e. the Warburg effect). The expressions of glycolysis-related gene were analyzed.

RESULTS

Viability, migration and survival of miR-181a-transfected MDA-MB-231 cells were all significantly reduced. miR-181a inhibited glycolysis in TNBC cells by reducing the rates of glucose uptake and lactate production and a substantial downregulation of factors known to contribute to the Warburg effect, including the serine/threonine kinase, AKT3, hypoxia-inducible factor-1α (HIF-1α) and progesterone receptor membrane component 1 (PGRMC1).

CONCLUSION

Our results demonstrate that miR-181a may regulate glycolysis in MDA-MB-231 TNBC cells, potentially via interference with components of the AKT3-HIF-1α and PGRMC1 pathways. These results suggest that miR-181a might be developed as a therapeutic agent for use in antineoplastic regimens directed at TNBC and PGRMC1-overexpressing breast cancers.

Mosaic pathogenic variants in AKT3 cause capillary malformation and undergrowth

Capillary malformations are slow-flow vascular malformations that affect the microcirculation including capillaries and post capillary venules and can be associated with growth differences. Specifically, the association of capillary malformations with undergrowth is a vastly understudied vascular syndrome with few reports of genetic causes including PIK3CA, GNAQ, and GNA11. Recently, a somatic pathogenic variant in AKT3 was identified in one child with a cutaneous vascular syndrome similar to cutis marmorata telangiectatica congenita, undergrowth, and no neurodevelopmental features. Here, we present a male patient with a capillary malformation and undergrowth due to a somatic pathogenic variant in AKT3 to confirm this association. It is essential to consider that mosaic pathogenic variants in AKT3 can cause a wide spectrum of disease. There is a need for future studies focusing on capillary malformations with undergrowth to understand the underlying mechanism.

MiR-181a-5p inhibits uveal melanoma development by targeting GNAQ and AKT3

Uveal melanoma (UM) is the most common primary intraocular malignant tumor type in adults. Even after the treatment of the ocular tumor, the prognosis of patients with metastasis remains poor. Hence, an urgent unmet need exists to identify novel approaches to treat advanced UM. Previous studies have revealed G subunit alpha Q and alpha 11 (GNAQ/11) mutations in more than 85% of patients with UM, thus indicating the importance of GNAQ and downstream signaling pathways in UM occurrence. Here, we demonstrate that microRNA (miR)-181a-5p, a small non-coding RNA, effectively inhibited the viability, proliferation, and colony formation but induced apoptosis of UM cells. Furthermore, silencing GNAQ or AKT3 mimicked the anti-UM effects of miR-181a-5p, whereas overexpression of GNAQ or AKT3 rescued the anti-UM effects induced by miR-181a-5p. In addition, miR-181a-5p had a stronger effect in decreasing the viability of GNAQ mutant than GNAQ wild-type cells. Moreover, miR-181a-5p suppressed the total expression and phosphorylation of members of the ERK and PI3K/AKT/mTOR signaling pathways. Importantly, miR-181a-5p potently inhibited the growth of UM xenografts in nude mice. MiR-181a-5p also decreased the expression of Ki67, GNAQ, and AKT3, and induced the expression of cleaved-caspase3 in UM tumors. These results suggest that miR-181a-5p inhibits UM development by targeting GNAQ and AKT3.

MiR-338-3p Is a Biomarker in Neonatal Acute Respiratory Distress Syndrome (ARDS) and Has Roles in the Inflammatory Response of ARDS Cell Models

To investigate the association between serum miR-338-3p levels and neonatal acute respiratory distress syndrome (ARDS) and its mechanism. The relative miR-338-3p expression in serum was detected by quantitative real-time RT-PCR. Interleukin-1beta (IL-1β), IL-6, and tumor necrosis factor-alpha (TNF-α) levels were detected by ELISAs. A receiver operating characteristic (ROC) curve analysis of serum miR-338-3p evaluated the diagnosis of miR-338-3p in neonatal ARDS. Pearson's correlation analysis evaluated the correlation between serum miR-338-3p and neonatal ARDS clinical factors. Flow cytometry evaluated apoptosis, and a CCK-8 assay assessed cell viability. A luciferase assay evaluated the miR-338-3p/AKT3 relationship. The miR- 338-3p expression was decreased in neonatal ARDS patients and in lipopolysaccharide (LPS)-treated cells. The ROC curve showed the accuracy of miR-338-3p for evaluating neonatal ARDS patients. The correlation analysis demonstrated that miR-338-3p was related to PRISM-III, PaO2/FiO2, oxygenation index, IL-1β, IL-6, and TNF-α in neonatal ARDS patients. MiR-338-3p overexpression inhibited the secretion of inflammatory components, stifled cell apoptosis, and LPS-induced advanced cell viability. The double-luciferase reporter gene experiment confirmed that miR-338-3p negatively regulates AKT3 mRNA expression. Serum miR-338-3p levels were related to the diagnosis and severity of neonatal ARDS, which may be attributed to its regulatory effect on inflammatory response in ARDS.

The ClinGen Brain Malformation Variant Curation Expert Panel: Rules for somatic variants in AKT3, MTOR, PIK3CA, and PIK3R2

PURPOSE

Postzygotic (somatic) variants in the mTOR pathway genes cause a spectrum of distinct developmental abnormalities. Accurate classification of somatic variants in this group of disorders is crucial for affected individuals and their families.

METHODS

The ClinGen Brain Malformation Variant Curation Expert Panel was formed to curate somatic variants associated with developmental brain malformations. We selected the genes AKT3, MTOR, PIK3CA, and PIK3R2 as the first set of genes to provide additional specifications to the 2015 American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) sequence variant interpretation guidelines, which currently focus solely on germline variants.

RESULTS

A total of 24 of the original 28 ACMG/AMP criteria required modification. Several modifications used could be applied to other genes and disorders in which somatic variants play a role: 1) using variant allele fraction differences as evidence that somatic mutagenesis occurred as a proxy for de novo variation, 2) incorporating both somatic and germline evidence, and 3) delineating phenotype on the basis of variable tissue expression.

CONCLUSION

We have established a framework for rigorous interpretation of somatic mosaic variants, addressing issues unique to somatic variants that will be applicable to many genes and conditions.

MiR-22-3p and miR-29a-3p synergistically inhibit hepatic stellate cell activation by targeting AKT3

Hepatic fibrosis (HF) is a worldwide health problem for which there is no medically effective drug treatment at present, and which is characterized by activation of hepatic stellate cells (HSCs) and excessive extracellular matrix (ECM) deposition. The HF model in cholestatic rats by ligating the common bile duct was induced and the differentially expressed miRNAs in the liver tissues were analyzed by microarray, which showed that miR-22-3p and miR-29a-3p were significantly downregulated in bile-duct ligation (BDL) rat liver compared with the sham control. The synergistic anti-HF activity and molecular mechanism of miR-22-3p and miR-29a-3p by targeting AKT serine/threonine kinase 3 (AKT3) in HSCs were explored. The expression levels of miR-22-3p and miR-29a-3p were downregulated in activated LX-2 and human primary normal hepatic fibroblasts (NFs), whereas AKT3 was found to be upregulated in BDL rat liver and activated LX-2 cells. The proliferation, colony-forming, and migration ability of LX-2 were inhibited synergistically by miR-22-3p and miR-29a-3p. In addition, cellular senescence was induced and the expressions of the LX-2 fibrosis markers COL1A1 and α-SMA were inhibited by miR-22-3p and miR-29a-3p synergistically. Subsequently, these two miRNAs binding to the 3'UTR of AKT3 mRNA was predicted and evidenced by the luciferase reporter assay. Furthermore, the proliferation, migration, colony-forming ability, and the expression levels of COL1A1 and α-SMA were promoted and cellular senescence was inhibited by AKT3 in LX-2 cells. Thus, miR-22-3p/miR-29a-3p/AKT3 regulates the activation of HSCs, providing a new avenue in the study and treatment of HF.

LncRNA PVT1 is a novel mediator promoting the angiogenesis response associated with collateral artery formation

AIMS

Angiogenesis plays a key role in coronary collateral circulation (CCC), the compensatory formation of new blood vessels during chronic total coronary occlusion. This study aimed to determine whether plasmacytoma variant translocation 1 (PVT1), a long non-coding (lnc) RNA involved in tumor angiogenesis, plays a role in regulating angiogenesis during chronic coronary ischemia.

MAIN METHODS

Patients with coronary artery disease, and ≥90% stenosis, were examined and divided into "Good" and "Poor" CCC groups based on Rentrop Cohen classification. RNA samples were obtained from all patients, as well as from oxygen and glucose-deprived (OGD) HUVECs. PVT1, miR-15b-5p and AKT3 levels were measured with RT-qPCR or Western blot, while HUVEC migration and angiogenesis were detected by, respectively, wound-healing and tube formation assays. Luciferase reporter assay confirmed direct PVT1-miR-15b-5p binding.

KEY FINDINGS

Increased PVT1 was found in "Good CCC" patient plasma, along with being highly expressed among OGD HUVECs; PVT1 knockdown reduced HUVEC migration, tube formation, and pro-angiogenic factor expression. Conversely, OGD HUVECs had downregulated miR-15b-5p, and miR-15b-5p overexpression significantly depressed their angiogenic capabilities. These PVT1 knockdown- or miR-15b-5p overexpression-associated reductions in angiogenic effects were reversed by AKT3 overexpression. In vivo, neovascularization and functioning in both ischemic mice hind-limbs and infarcted myocardium injected with ADV-sh-PVT1 were reduced, which were ameliorated by concurrent antagomiR-15b-5p injections.

SIGNIFICANCE

Circulating PVT1 may serve as a useful biomarker to distinguish between good versus poor CCC, as it is involved in orchestrating angiogenesis via the miR-15b-5p-AKT3 axis; it thus has potential as a target for treating ischemic disease.

Circ_0011232 contributes to hepatocellular carcinoma progression through miR-503-5p/AKT3 axis

BACKGROUND

Hepatocellular carcinoma (HCC) is a type of primary liver cancer with high mortality. Circular RNAs (circRNAs) have been confirmed to be involved in the development of HCC, but the functions of circ_0011232 in HCC remain ill-defined.

METHODS

Quantitative real-time polymerase chain reaction, western blot assay, or immunohistochemistry assay was performed to determine the levels of circ_0011232, miR-503-5p, and AKT3. RNase R assay and actinomycin D assay were conducted to analyze the feature of circ_0011232. Cell Counting Kit-8 assay, 5-ethynyl-2'-deoxyuridine assay, colony formation assay, flow cytometry analysis, wound-healing assay, and transwell assay were conducted to evaluate HCC cell proliferation, colony formation, apoptosis, migration, and invasion. Dual-luciferase reporter assay was carried out to confirm the relationships among circ_0011232, miR-503-5p, and AKT3. The murine xenograft assay was conducted to verify the function of circ_0011232 in tumor growth in vivo.

RESULTS

Circ_0011232 and AKT3 were upregulated, while miR-503-5p was decreased in HCC tissues and cells. Circ_0011232 knockdown repressed HCC cell proliferation, colony formation, migration, and invasion, and promoted apoptosis in vitro and blocked tumor growth in vivo. MiR-503-5p was a target of circ_0011232. MiR-503-5p inhibition reversed the effects of circ_0011232 knockdown on HCC cell development. Moreover, AKT3 was confirmed to be a target of miR-503-5p, and AKT3 overexpression abolished the inhibitory effects on HCC cell progression caused by miR-503-5p.

CONCLUSION

Circ_0011232 facilitated HCC progression via miR-503-5p/AKT3 axis, which might provide a novel treatment strategy for HCC.

Genetic Deficiency of MicroRNA-15a/16-1 Confers Resistance to Neuropathological Damage and Cognitive Dysfunction in Experimental Vascular Cognitive Impairment and Dementia

Chronic cerebral hypoperfusion-derived brain damage contributes to the progression of vascular cognitive impairment and dementia (VCID). Cumulative evidence has shown that microRNAs (miRs) are emerging as novel therapeutic targets for CNS disorders. In this study, it is sought to determine the regulatory role of miR-15a/16-1 in VCID. It is found that miR-15a/16-1 knockout (KO) mice exhibit less cognitive and sensorimotor deficits following VCID. Genetic deficiency of miR-15a/16-1 in VCID mice also mitigate myelin degeneration, axonal injury, and neuronal loss. Mechanistically, miR-15a/16-1 binds to the 3'-UTR of AKT3 and IL-10RA. Genetic deletion of miR-15a/16-1 increases AKT3 and IL-10RA expression in VCID brains, and intranasal delivery of AKT3 and IL-10RA siRNA-loaded nanoparticles partially reduce brain protection and cognitive recovery in miR-15a/16-1 KO mice after VCID. In conclusion, the miR-15a/16-1-IL/10RA/AKT3 axis plays a critical role in regulating vascular brain damage and cognitive decline after VCID. Targeting miR-15a/16-1 is a novel therapeutic approach for the treatment of VCID.

Role of LINC01133 in Osteogenic Differentiation of Dental Pulp Stem Cells by Targeting miR-199b-5p

PURPOSE

Recently, increasing attention has been paid to the function of long non-coding RNAs (lncRNAs) in osteogenic differentiation (OD) of dental pulp stem cells (DPSCs). LINC01133 was reported to have a close relationship with tumorigenesis for multiple cancers, but no study has yet explored the role of LINC01133 in modulating OD of DPSCs.

MATERIALS AND METHODS

Alizarin red S (ARS) staining and alkaline phosphatase (ALP) staining were perfomed to assess the OD potential of DPSCs. Osteogenic markers including runt-related transcription factor 2 (RUNX2), osterix (OSX) and ALP expression levels in DPSCs were monitored by qRT-PCR and Western blot before and after cell transfection. Luciferase reporter gene assay detected the relationship between LINC01133 and miR-199b-5p.

RESULTS

The expression of LINC01133 was low, while miR-199b-5p was increasingly expressed during OD of DPSCs. Overexpression of LINC01133 in DPSCs resulted in decreased expression of RUNX2, OSX, ALP, DSPP and DMP1, whose expression was reversed in DPSCs after transfections of miR-199b-5p overexpression. Co-transfection of pcDNA3.1-LINC01133 and miR-199b-5p mimic led to elevated expression of RUNX2, OSX, ALP, DSPP and DMP1 compared with pcDNA3.1-LINC01133 transfection alone. LINC01133 served as a sponge of miR-199b-5p. AKT3 was verified as a downstream effector of miR-199b-5p in DPSCs.

CONCLUSION

LINC01133 inhibits the OD of DPSCs by upregulating AKT3 via sponging miR-199b-5p, which may act as a potential diagnostic biomarker for dentin regeneration in the dental pulp.

circHIPK3 regulates cell proliferation and migration by sponging microRNA-124 and regulating serine/threonine kinase 3 expression in esophageal squamous cell carcinoma

Circular RNAs (circRNAs) are a type of important non-coding RNAs that widely involve in the physiological and pathophysiological process. Recent research has established a link between circHIPK3 and the malignant activity of cancer cells. However, circHIPK3’ role in esophageal squamous cell carcinoma (ESCC) still needs more focus. To determine the prognostic value of circHIPK3 in patients with ESCC, the expression of circHIPK3 was quantified in 32 pairs of ESCC using real-time polymerase chain reaction (RT-qPCR). Then, the correlation between circHIPK3 expression and clinical characteristics of patients was also analyzed. The function of circHIPK3 in the development of ESCC was investigated using cell biology studies and bioinformatics. The results showed that the expression of circHIPK3 was considerably higher in tumor tissues from ESCC patients than that of adjacent tissues, which was associated with a poor prognosis. Additionally, silencing of circHIPK3 expression retarded esophageal cancer cell proliferation, migration and epithelial-mesenchymal transition (EMT) in vitro, as well as the growth in vivo. Mechanistically, we discovered that circHIPK3 behaved like a sponge, absorbing microRNA-124 (miR-124) and promoting serine/threonine kinase 3 (AKT3) expression. Our findings indicate that circHIPK3 acts as an oncogene in ESCC and that the circHIPK3-AKT3 axis may be a therapeutic target for patients with ESCC.

The genetic basis of neurocranial size and shape across varied lab mouse populations

Brain and skull tissues interact through molecular signalling and mechanical forces during head development, leading to a strong correlation between the neurocranium and the external brain surface. Therefore, when brain tissue is unavailable, neurocranial endocasts are often used to approximate brain size and shape. Evolutionary changes in brain morphology may have resulted in secondary changes to neurocranial morphology, but the developmental and genetic processes underlying this relationship are not well understood. Using automated phenotyping methods, we quantified the genetic basis of endocast variation across large genetically varied populations of laboratory mice in two ways: (1) to determine the contributions of various genetic factors to neurocranial form and (2) to help clarify whether a neurocranial variation is based on genetic variation that primarily impacts bone development or on genetic variation that primarily impacts brain development, leading to secondary changes in bone morphology. Our results indicate that endocast size is highly heritable and is primarily determined by additive genetic factors. In addition, a non-additive inbreeding effect led to founder strains with lower neurocranial size, but relatively large brains compared to skull size; suggesting stronger canalization of brain size and/or a general allometric effect. Within an outbred sample of mice, we identified a locus on mouse chromosome 1 that is significantly associated with variation in several positively correlated endocast size measures. Because the protein-coding genes at this locus have been previously associated with brain development and not with bone development, we propose that genetic variation at this locus leads primarily to variation in brain volume that secondarily leads to changes in neurocranial globularity. We identify a strain-specific missense mutation within Akt3 that is a strong causal candidate for this genetic effect. Whilst it is not appropriate to generalize our hypothesis for this single locus to all other loci that also contribute to the complex trait of neurocranial skull morphology, our results further reveal the genetic basis of neurocranial variation and highlight the importance of the mechanical influence of brain growth in determining skull morphology.

LncRNA MALAT1 promotes osteogenic differentiation through the miR-217/AKT3 axis: a possible strategy to alleviate osteoporosis

BACKGROUND

Accumulating evidence demonstrates that long non-coding RNAs (lncRNAs) are associated with the development of osteoporosis. This study aimed to investigate the effect of MALAT1 on osteogenic differentiation in osteoporosis.

METHODS

The MALAT1 levels were detected by Real-time Polymerase Chain Reaction (RT-qPCR). Moreover, the levels of osteogenic differentiation-related factors (Bmp4, Col1a1, and Spp1) were measured by RT-qPCR and western blot. Alkaline phosphatase (ALP) activity was detected using ALP staining assay.

RESULTS

The MALAT1 levels were downregulated in hindlimb unloading (HU) mice and simulated microgravity (MG) treated MC3T3-E1 cells. Moreover, MG treatment induced the downregulation of the expression of ALP, BMP4, Col1a1 and Spp1, while overexpression of MALAT1 abolished the downregulation. MG also inhibited ALP activity, while MALAT1 reversed the effect. Furthermore, miR-217 was identified as a target of MALAT1, and AKT3 was verified as a target of miR-217. Overexpression of miR-217 rescued the promotion of osteogenic differentiation induced by MALAT1 in MG treated cells. Knockdown of AKT3 abolished the facilitation of osteogenic differentiation induced by downregulation of miR-217.

CONCLUSION

MALAT1 promotes osteogenic differentiation through regulating miR-217/AKT3 axis, suggesting that MALAT1 is a potential target to alleviate osteoporosis.

LINC01207 promotes prostate cancer progression by sponging miR-1182 to upregulate AKT3

Prostate cancer (PC) is recognized as a common malignancy in male patients. Long non-coding RNA (lncRNA) has been implicated in the development of PC. Recently, long intergenic non-protein coding RNA 1207 (LINC01207) has been reported to regulate the carcinogenesis of multiple cancer types. However, its role in the progression of PC remains to be determined. The aim of the present study was to investigate the expression profile, clinicopathological implication and molecular mechanism of action of LINC01207 in the progression of PC. LINC01207 expression levels were compared between PC tumor and paired normal tissue samples from The Cancer Genome Atlas. The expression of LINC01207 was further analyzed in PC cell lines and a normal prostatic cell line. The role of LINC01207 in proliferation, migration and invasion of PC cells was examined using small interfering RNA-mediated silencing. Western blot analysis was used to investigate the changes in protein levels underlying the mechanism of action of LINC01207. The role of LINC01207 in tumorigenesis was evaluated in a xenograft model. LINC01207 was upregulated in PC tumor samples from TCGA data compared with paired normal tissue. LINC01207 expression was significantly increased in PC cells and tumor tissues compared with in normal prostate cells (RWPE1) and normal prostate tissues, respectively. Furthermore, LINC01207 silencing inhibited PC cell proliferation and colony formation and induced apoptosis. Mechanistic experiments showed that LINC01207 promoted carcinogenesis by sponging miR-1182 to regulate the protein levels of AKT3 in PC cell lines. Thus, the findings of the present study indicated that LINC01207 might play a role in the tumorigenesis of PC and may serve as a therapeutic target for PC treatment.

AKT Isoforms Interplay in High-Grade Serous Ovarian Cancer Prognosis and Characterization

Simple Summary

New therapeutical strategies are needed to improve survival in high-grade serous ovarian cancer (HGSOC) patients. AKT inhibitors are promising agents able to act in synergy with PARP inhibitors and platinum-based therapies, but the subset of patients who could benefit from this approach is still unclear. We analyzed AKT isoforms expression in a retrospective cohort and we identified four AKT expression groups related to patients’ survival, tumor morphology and the BRCA status that could help in stratifying patients for future clinical trials.

Abstract

High-grade serous ovarian cancer (HGSOC) is among the deadliest gynecological malignancies. The acquired resistance to platinum-based therapies and the intrinsic heterogeneity of the disease contribute to the low survival rate. To improve patients’ outcomes, new combinatorial approaches able to target different tumor vulnerabilities and enhance the efficacy of the current therapies are required. AKT inhibitors are promising antineoplastic agents able to act in synergy with PARP inhibitors, but the spectrum of patients who can benefit from this combination is unclear, since the role of the three different isoforms of AKT is still unknown. Here, we study the expression of AKT isoforms on a retrospective cohort of archive tissue by RT-droplet digital PCR (ddPCR) analyzing their association with the clinicopathological features of patients. Based on AKT1/AKT2 and AKT1/AKT3 ratios, we define four AKT classes which were related to patients’ survival, tumor morphology and BRCA1 expression. Moreover, our results show that high AKT3 expression levels were frequently associated with tumors having classic features, a low number of mitoses and the presence of psammoma bodies. Overall, our study obtains new insights on AKT isoforms and their associations with the clinicopathological features of HGSOC patients. These evidences could help to better define the subsets of patients who can benefit from AKT and PARP inhibitors therapy in future clinical trials.

AKT Isoforms in the Immune Response in Cancer

AKT is a protein kinase that exists in three isoforms: AKT1, AKT2, and AKT3. Though similar in structure, these isoforms display different effects. AKT is activated downstream of PI3K, and together, this signaling pathway helps regulate cellular processes including cell growth, proliferation, metabolism, survival, and apoptosis. Disruption in these pathways has been associated with disorders including cardiovascular diseases, developmental disorders, inflammatory responses, autoimmune diseases, neurologic disorders, type 2 diabetes, and several cancers. In cancer, deregulation in the PI3K/AKT pathway can be manifested as tumorigenesis, pathological angiogenesis, and metastasis. Increased activity has been correlated with tumor progression and resistance to cancer treatments. Recent studies have suggested that inhibition of the PI3K/AKT pathway plays a significant role in the development, expansion, and proliferation of cells of the immune system. Additionally, AKT has been found to play an important role in differentiating regulatory T cells, activating B cells, and augmenting tumor immunosurveillance. This emphasizes AKT as a potential target for inhibition in cancer therapy. This chapter reviews AKT structure and regulation, its different isoforms, its role in immune cells, and its modulation in oncotherapy.

Regulation of COL1A2, AKT3 genes, and related signaling pathway in the pathology of congenital talipes equinovarus

Congenital talipes equinovarus (CTEV) is one of the most common congenital limb defects in children, which is a multifactorial and complex disease that associates with many unknown genetic, social-demographic, and environmental risk factors. Emerging evidence proved that gene expression or mutation might play an important role in the occurrence and development of CTEV. However, the underlying reasons and involved mechanisms are still not clear. Herein, to probe the potential genes and related signaling pathways involved in CTEV, we first identified the differentially expressed genes (DEGs) by mRNA sequencing in pediatric patients with CTEV compared with normal children. The gene of COL1A2 was upregulated, and AKT3 was downregulated at the transcriptional level. Western blot and quantitative polymerase chain reaction (qRT-PCR) results also showed that the expression of COL1A2 in CTEV was enhanced, and the AKT3 was decreased. Furthermore, the COL1A2 Knock-in (+COL1A2) and AKT3 Knock-out (-AKT3) transgenic mice were used to verify the effects of these two genes in the CTEV, and the results of which showed that both COL1A2 and AKT3 were closely related to the CTEV. We also investigated the effect of the PI3K-AKT3 signaling pathway in CTEV by measuring the relative expression of several key genes using Western blot and qRT-PCR. In line with the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis data, the PI3K-AKT3 signaling pathway might play a potentially important role in the regulation of pathological changes of CTEV. This study will provide new ideas for the mechanism investigation and prenatal diagnosis of CTEV.

Hypomethylation-driven AKT Serine/Threonine Kinase 3 promotes testicular germ cell tumors proliferation and negatively correlates to immune infiltration

AKT Serine/Threonine Kinase 3 (AKT3) has been reported to play an important role in different tumors. However, its clinical value, biological function, and molecular mechanism in testicular germ cell tumors (TGCT) remains unclear. In the current study, we applied the Gene Set Cancer Analysis (GSCA), UCSC XENA, Gene Expression Omnibus (GEO), the Human Protein Atlas (HPA), LinkedOmics, DiseaseMeth version 2.0, TISIDB, and other databases for TGCT data mining. Then, we investigated AKT3’s mechanism of action and clinical survival significance via bioinformatics followed by in vitro experiments. We found that AKT3 was upregulated and had frequent copy number amplifications in TGCT, which were associated with poor survival outcomes of patients. On the other hand, mutations that led to AKT3 loss-of-function were correlated to a better prognosis in patients. Moreover, AKT3 silencing significantly inhibited the proliferation, DNA synthesis and colony formation of NCCIT cells (a TGCT cell line). AKT3 might participate in TGCT progression through multiple signaling pathways, such as ErbB, oxidative phosphorylation, and affecting tumor immune infiltration. Also, the upregulation of AKT3 mRNA expression might be driven by the hypomethylation of its promoter region. Overall, AKT3 is a potential TGCT oncogene and can be further used as a therapeutic target.

AGTR1 Inhibits the Progression of Lung Adenocarcinoma

Purpose

The occurrence and development of lung adenocarcinoma (LUAD) are related to many factors. Multiple researches showed that the renin-angiotensin system (RAS) plays an important role in lung cancer. This research mainly focuses on angiotensin II receptor 1 (AT1R) encoding gene AGTR1, an important part of the RAS.

Methods

We comprehensively evaluated the expression of AGTR1 in pan-cancer based on RNA sequencing data obtained from The Cancer Genome Atlas (TCGA). We explored the correlation of AGTR1 with clinicopathological features, prognosis and tumor microenvironment in LUAD. We also explored the mechanism through enrichment analysis and verified it with cell lines and tissue samples.

Results

We found that AGTR1 was less expressed in most tumors and related to prognosis based on the TCGA database. To further explore its mechanism, we mainly focused on LUAD. Combined with the verification results in the GEO database, AGTR1 was associated with a better prognosis in LUAD. High expression of AGTR1 was associated with less lymph node metastasis (P=0.007) and MET mutation (P=0.019). High expression of AGTR1 was related to the anti-tumor immune microenvironment with high infiltration of B cells, myeloid dendritic cells, monocytes, and low infiltration of myeloid-derived suppressor cells (all P<0.05). Enrichment analysis and in vitro verification results showed that AGTR1 was likely to play a role in LUAD through the PI3K/AKT3 pathway. Finally, we verified the above results through tissue samples and the construction of AGTR1 overexpressing cells.

Conclusion

AGTR1 inhibits the progression of lung adenocarcinoma through the PI3K/AKT3 pathway.

N6-methyladenosine-modified long non-coding RNA AGAP2-AS1 promotes psoriasis pathogenesis via miR-424-5p/AKT3 axis

BACKGROUND

Psoriasis is a chronic, complicated, and recurrent inflammatory skin disease. However, the precise molecular mechanisms remain largely elusive and the present treatment is unsatisfactory.

OBJECTIVE

This study aimed to unravel the functions of long noncoding RNA (lncRNA) AGAP2-AS1 and its biological mechanism in psoriasis pathogenesis, hinting for the new therapeutic targets in psoriasis.

METHODS

The expression of AGAP2-AS1 in the skin tissue of psoriasis patients and healthy controls were detected by qRT-PCR and RNAscope®. Cell Counting Kit‑8 (CCK8) and clone formation assays were utilized to assess proliferation. Methylated RNA immunoprecipitation (MeRIP) was performed to detect the N⁶-methyladenosine (m⁶A) modification. RNA immunoprecipitation (RIP) was used to detect the interaction of AGAP2-AS1 with YTH domain family 2(YTHDF2). The relationships among AGAP2-AS1, miR-424-5p and AKT3 were examined by dual-luciferase reporter assay and RIP assay.

RESULTS

We found that AGAP2-AS1 level was upregulated in the skin tissue of psoriasis patients than that of healthy controls and AGAP2-AS1 could promote proliferation and inhibit apoptosis of keratinocytes. Methyltransferase like 3(METTL3)-mediated m6A modification suppressed the expression of AGAP2-AS1 via YTHDF2-dependent AGAP2-AS1 stability. Thus, downregulation of METTL3 resulted in the upregulation of AGAP2-AS1 in psoriasis. AGAP2-AS1 functioned as a competitive endogenous RNA by sponging miR-424-5p to upregulate AKT3, activate AKT/mTOR pathway, as well as promote cell proliferation in keratinocytes.

CONCLUSION

AGAP2-AS1 is upregulated in the skin tissue of psoriasis patients and m⁶A methylation was involved in its upregulation. AGAP2-AS1 promotes keratinocyte proliferation through miR-424-5p/AKT/mTOR axis and may be a promising target for psoriasis therapy.

NR2F1-AS1/miR-190a/PHLDB2 Induces the Epithelial-Mesenchymal Transformation Process in Gastric Cancer by Promoting Phosphorylation of AKT3

The median survival time of patients with advanced gastric cancer (GC) who received radiotherapy and chemotherapy was <1 year. Epithelial–mesenchymal transformation (EMT) gives GC cells the ability to invade, which is an essential biological mechanism in the progression of GC. The long non-coding RNA (lncRNA)-based competitive endogenous RNA (ceRNA) system has been shown to play a key role in the GC-related EMT process. Although the AKT pathway is essential for EMT in GC, the relationship between AKT3 subtypes and EMT in GC is unclear. Here, we evaluated the underlying mechanism of ceRNA involving NR2F1-AS1/miR-190a/PHLDB2 in inducing EMT by promoting the expression and phosphorylation of AKT3. The results of bioinformatics analysis showed that the expression of NR2F1-AS1/miR-190a/PHLDB2 in GC was positively associated with the pathological features, staging, poor prognosis, and EMT process. We performed cell transfection, qRT-PCR, western blot, cell viability assay, TUNEL assay, Transwell assay, cell morphology observation, and double luciferase assay to confirm the regulation of NR2F1-AS1/miR-190a/PHLDB2 and its effect on EMT transformation. Finally, GSEA and GO/KEGG enrichment analysis identified that PI3K/AKT pathway was positively correlated to NR2F1-AS1/miR-190a/PHLDB2 expression. AKT3 knockout cells were co-transfected with PHLDB2-OE, and the findings revealed that AKT3 expression and phosphorylation were essential for the PHLDB2-mediated EMT process. Thus, our results showed that NR2F1-AS1/miR-190a/PHLDB2 promoted the phosphorylation of AKT3 to induce EMT in GC cells. This study provides a comprehensive understanding of the underlying mechanism involved in the EMT process as well as the identification of new EMT markers.

The variation in promoter sequences of the Akt3 gene between cow and buffalo revealed different responses against mastitis

Background

Serine/threonine kinase 3 (AKT3) is a protein-coding gene that is associated with several cattle immune diseases including different tumors and cancers. The objective of this study was to investigate the differences in structures and functions of AKT3 of cow and buffalo cattle.

Methods

The sequence differences of gene-coding sequence (CDS) and core promoter region of AKT3 in cow and buffalo were analyzed by using bioinformatics tools and PCR sequencing. Also, the functional analysis of promoter regulating gene expression by RT-PCR was performed using 500 Holstein cows and buffalos. And, evaluation of AKT3 inflammatory response to the lipopolysaccharide (LPS)-induced mastitis was performed between both species.

Results

The results revealed the variation in 6 exons out of 13 exons of the two species of CDS. Also, 4 different regions in 3-kb promoters of the AKT3 gene were significantly different between cow and buffalo species, in which cow’s AKT3 promoter sequence region was started from − 371 to − 1247, while in buffalo, the sequence was started from − 371 to − 969 of the promoter crucial region. Thus, the promoter was overexpressed in cows compared to buffaloes. As a result, significant differences (P < 0.05) between the two species in the AKT3 gene expression level related to the LPS stimulation in their mammary epithelial cell line.

Conclusions

This study emphasized the great importance of the structural differences of AKT3 between the animal species on their different responses against immune diseases like mastitis.

Circ_0016760 accelerates non-small-cell lung cancer progression through miR-646/AKT3 signaling in vivo and in vitro

BACKGROUND

Currently, the prognosis of non-small-cell lung cancer (NSCLC) patients remains dismal due to recurrence and metastasis. The purpose of our study was to explore the role of circular RNA_0016760 (circ_0016760) in NSCLC progression and its associated mechanism.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was implemented to measure the expression of circ_0016760, microRNA-646 (miR-646) and AK strain thymoma serine/threonine kinase 3 (AKT3). The protein level of AKT3 was examined by Western blot assay. Cell Counting Kit 8 assay, transwell assays, and flow cytometry were conducted to analyze cell proliferation, metastasis, and apoptosis. Dual-luciferase reporter assay was used to confirm the interactions that were predicted by bioinformatics software (Circular RNA Interactome and TargetScan). A xenograft tumor model was built to investigate the role of circ_0016760 in vivo.

RESULTS

Circ_0016760 and AKT3 were highly expressed in NSCLC tissue specimens and cell lines. Circ_0016760 interference suppressed cell proliferation, migration, and invasion and promoted the apoptosis of NSCLC cells. Circ_0016760 interacted with miR-646 and negatively regulated its expression. MiR-646 silencing partly counteracted circ_0016760 knockdown-mediated influences in NSCLC cells. MiR-646 bound to the AKT3 3' untranslated region in NSCLC cells, and miR-646 overexpression-induced effects in NSCLC cells were partly overturned by the addition of AKT3 overexpression plasmid. Circ_0016760 silencing reduced the expression of AKT3 through enhancing miR-646 expression. Circ_0016760 knockdown suppressed NSCLC tumor growth in vivo.

CONCLUSION

Circ_0016760 played an oncogenic role to promote the proliferation, migration, and invasion and restrained the apoptosis of NSCLC cells via miR-646/AKT3 signaling.

CircNRIP1 Encapsulated by Bone Marrow Mesenchymal Stem Cell-Derived Extracellular Vesicles Aggravates Osteosarcoma by Modulating the miR-532-3p/AKT3/PI3K/AKT Axis

Emerging evidence indicates that extracellular vesicle (EV)-encapsulated circRNAs have the potential diagnostic and prognostic values for malignancies. However, the role of circNRIP1 in osteosarcoma remains unclear. We herein investigated the therapeutic potential of circNRIP1 delivered by bone marrow mesenchymal stem cell–derived EVs (BMSC-EVs) in osteosarcoma. The expression of circNRIP1 was examined in the clinical tissue samples of osteosarcoma patients, after which the downstream genes of circNRIP1 were bioinformatically predicted. Gain- and loss-of function assays were then performed in osteosarcoma cells with manipulation of circNRIP1 and miR-532-3p expression. EVs isolated from BMSCs were characterized and co-cultured with osteosarcoma cells to examine their effects on cell phenotypes, as reflected by CCK-8 and Transwell assays. Further, a mouse model of tumor xenografts was established for in vivo substantiation. circNRIP1 was upregulated in osteosarcoma tissues and cells. Overexpression of circNRIP1 promoted the proliferative, migratory, and invasive potential of osteosarcoma cells. Co-culture data showed that BMSC-EVs could transfer circNRIP1 into osteosarcoma cells where it competitively bound to miR-532-3p and weakened miR-532-3p’s binding ability to AKT3. By this mechanism, the PI3K/AKT signaling pathway was activated and the malignant characteristics of osteosarcoma cells were stimulated. In vivo experimental results unveiled that circNRIP1-overexpressing BMSC-EVs in nude mice resulted in enhanced tumor growth. In conclusion, the BMSC-EV-enclosed circNRIP1 revealed a new molecular mechanism in the pathogenesis of osteosarcoma, which might provide a novel therapeutic target for osteosarcoma.

CircWHSC1 regulates malignancy and glycolysis by the miR-212-5p/AKT3 pathway in triple-negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is the most aggressive malignant tumor in breast cancer (BC). Circular RNA circWHSC1 (circWHSC1) is connected with the progression of tumors. However, the role and regulatory mechanism of circWHSC1 in TNBC are unclear.

METHODS

The expression of circWHSC1, microRNA (miR)-212-5p, and protein kinase B-3 (AKT3) mRNA in BC tissues and/or cells was examined by quantitative real-time polymerase chain reaction (qRT-PCR). The viability, colony formation, migration, invasion, and apoptosis of TNBC cells were determined by cell counting kit-8 (CCK-8), colony formation, transwell, or flow cytometry assays. The levels of glucose consumption and lactate production were assessed with commercial kits. The levels of hexokinase II (HK2) and AKT3 protein were detected by western blotting. The role of circWHSC1 in vivo was verified by tumor xenograft assay. The relationship between miR-212-5p and circWHSC1 or AKT3 was verified via dual-luciferase reporter and RNA pull-down assays.

RESULTS

CircWHSC1 was upregulated in BC tissues and cells. Also, circWHSC1 could discriminate BC tissues and paracancerous normal tissues. TNBC patients with high circWHSC1 possessed a poor prognosis. CircWHSC1 silencing reduced TNBC cell growth in vivo and repressed proliferation, migration, invasion, glycolysis, and induced apoptosis of TNBC cells in vitro. CircWHSC1 regulated AKT3 expression by sponging miR-212-5p. Silencing of miR-212-5p overturned circWHSC1 knockdown-mediated impacts on malignancy and glycolysis of TNBC cells. AKT3 overexpression reversed the inhibitory effect of miR-212-5p mimic on malignancy and glycolysis of TNBC cells.

CONCLUSIONS

CircWHSC1 accelerated malignancy and glycolysis of TNBC cells by the miR-212-5p/AKT3 axis. The research provided a potential prognostic biomarker and therapeutic target for TNBC.

MicroRNA Expression Profiles in Autism Spectrum Disorder: Role for miR-181 in Immunomodulation

BACKGROUND

MicroRNAs (miRNAs) are important regulators of molecular pathways in psychiatric disease. Here, we examine differential miRNAs expression in lymphoblastoid cell lines (LCLs) derived from 10 individuals with autism spectrum disorder (ASD) and compare them to seven typically developing unrelated age- and gender-matched controls and 10 typically developing siblings. Small RNAseq analysis identified miRNAs, and selected miRNAs were validated using quantitative real-time polymerase reaction (qRT-PCR). KEGG analysis identified target pathways, and selected predicted mRNAs were validated using qRT-PCR.

RESULTS

Small RNAseq analysis identified that multiple miRNAs differentiated ASD from unrelated controls and ASD from typically developing siblings, with only one, hsa-miR-451a_R-1, being in common. Verification with qRT-PCR showed that miR-320a differentiated ASD from both sibling and unrelated controls and that several members of the miR-181 family differentiated ASD from unrelated controls. Differential expression of AKT2, AKT3, TNF α and CamKinase II predicted by KEGG analysis was verified by qRT-PCR. Expression of CamKinase II βwas found to be correlated with the severity of stereotyped behavior of the ASD participants.

CONCLUSIONS

This study provides insight into the mechanisms regulating molecular pathways in individuals with ASD and identifies differentiated regulated genes involved in both the central nervous system and the immune system.

CircMYC regulates the mitochondrial respiration and cell viability via miR-516a-5p/AKT3 axis in acute myeloid leukemia

OBJECTIVE

Acute myeloid leukemia (AML) is a hematological malignancy with an aberrant proliferation of immature myeloid cells. This study aimed at exploring the regulatory function of circMYC in AML progression.

METHODS

Expression levels of CircMYC, miR-516a-5p, AKT3 and apoptosis-related proteins were determined by RT-qPCR and western blot. Cell viability and proliferation were examined by CCK8 assay and EdU assay. Annexin V/PI staining was used to assess cell apoptosis. Mitochondrial respiration function was confirmed by oxygen consumption rate (OCR). The relationships among circMYC, miR-516a-5p and AKT3 were detected by dual-luciferase reporter (DLR) assay, RNA-pull down assay and RNA immunoprecipitation (RIP) assay, respectively.

RESULTS

CircMYC was positively correlated with poor prognosis in AML patients (all P<0.05). Knockdown of circMYC decreased cell viability and OCR but increased cell apoptosis rates (all P<0.05), and miR-516a-5p overexpression displayed the similar trend. Mechanistically, the oncogenic effects of circMYC were achieved by sponging miR-516a-5p and increasing AKT3.

CONCLUSION

Decreased expression of circMYC could suppress AML progression by regulating miR-516a-5p/AKT3, suggesting a new therapeutic target in AML treatment.

MiR-20b-5p modulates inflammation, apoptosis and angiogenesis in severe acute pancreatitis through autophagy by targeting AKT3

BACKGROUND

Severe acute pancreatitis (SAP) is a common acute abdominal disease with high morbidity and mortality. However, the mechanism underlying SAP is still unclear.

METHODS

Cerulean and LPS (Cer-LPS) was used to establish a rat model and an in vitro model of SAP. qRT-PCR, western blot and IHC were determined to analyse the expression of mRNA and proteins. IL-1β, TNF-α and IL-6 levels were measured applying ELISA. H&E staining was determined to observe the pathological changes. Apoptosis was tested by AV-PI staining using flow cytometry. CCK8 assay was taken to detect cell viability. Cell migration was assessed by transwell assay. Tube formation assay was conducted to evaluate angiogenesis. Luciferase assay was used to detect relationship of miR-20b-5p and AKT3.

RESULTS

MiR-20b-5p was lowly expressed in SAP models both in vivo and in vitro. Overexpression of miR-20b-5p restrained inflammation and apoptosis in Cer-LPS treated pancreatic acinar cells. Furthermore, miR-20b-5p promoted the angiogenesis of vascular endothelial cells, since the viability, migration and the capability of tube formation were increased by miR-20b-5p. Mechanically, miR-20b-5p directly targeted AKT3 to promote autophagy. Furthermore, miR-20b-5p could prevent the inflammation, apoptosis and enhance angiogenesis via enhancing autophagy, which was verified in vivo.

CONCLUSION

This study demonstrated miR-20b-5p attenuates SAP through directly targeting AKT3 to regulate autophagy, subsequently inhibit inflammation and apoptosis, and promote angiogenesis. Our findings suggested a novel target of miR-20b-5p for the therapy of SAP.

CircRNA WHSC1 promotes non-small cell lung cancer progression via sponging microRNA-296-3p and up-regulating expression of AKT serine/threonine kinase 3

Background

Lung cancer is the most commonly diagnosed cancer and leading cause of cancer death, with 80%–85% of non‐small cell lung cancer (NSCLC). Circular RNAs (circRNAs) have been shown to be promising early diagnostic and therapeutic molecular biomarkers for NSCLC. However, biological role and regulatory mechanism of circRNA WHSC1 (circWHSC1) in NSCLC are unknown. Therefore, we aim to explore the function and mechanism of circWHSC1 in NSCLC oncogenesis and progression.

Methods

qRT‐PCR was used for circWHSC1 level evaluation; Kaplan‐Meier was used for survival analysis; bioinformatics, dual‐luciferase activity, and RNA pull‐down were used for evaluating competing endogenous RNA (ceRNA) network; cell viability, colony formation, apoptosis, migration, and invasion were used for cell function analysis; function gain and loss with rescue experiments were used for exploring mechanism of circWHSC1 in NSCLC development.

Results

Significantly up‐regulated circWHSC1 and down‐regulated microRNA‐296‐3p (miR‐296‐3p) were identified in NSCLC tissues and cells. Up‐regulated circWHSC1 was associated with poor prognosis in NSCLC patients. MiR‐296‐3p was sponged by circWHSC1, and AKT serine/threonine kinase 3 (AKT3) was target of miR‐296‐3p; meanwhile, miR‐296‐3p over‐expression significantly down‐regulated AKT3 expression, and co‐transfecting anti‐miR‐296‐3p rescued circWHSC1 silence caused AKT3 down‐regulation. CircWHSC1 silence significantly inhibited colony formation, viability, invasion, and migration, while increased NSCLC cell apoptosis, which were partially rescued by anti‐miR‐296‐3p.

Conclusion

CircWHSC1 is an independent indicator of poor prognosis in NSCLC patients, and functions as a ceRNA of miR‐296‐3p to up‐regulate AKT3, consequently promotes NSCLC cell growth and metastasis. Targeting circWHSC1 might be a prospective strategy for diagnosis, therapeutics, and prognosis of NSCLC.

Long non‑coding RNA LINC01224 promotes cell proliferation and inhibits apoptosis by regulating AKT3 expression via targeting miR‑485‑5p in endometrial carcinoma

Endometrial carcinoma (EC) is the most common cancer in women worldwide, yet little is known about the underlying molecular basis of EC development. LINC01224, a novel long non-coding (lnc)RNA, was recently identified as an oncogene in various types of cancer. However, the function and underlying mechanism of LINC01224 in EC is still unclear. A total of 50 pairs of tumor and adjacent normal tissue from patients with EC, three EC cell lines and one human normal endometrial stromal cell (ESC) line were subjected to reverse transcription-quantitative PCR assay to evaluate the expression levels of LINC01224. Cell Counting Kit-8, colony formation and flow cytometry assays were used to assess cell proliferation and apoptosis. Western blotting was used to measure expression levels of apoptosis- and proliferation-associated proteins and AKT3 protein. A xenograft model of HEC1A cells was established to validate the in vivo function of LINC01224 in EC tumor growth. Starbase 3.0 database prediction and luciferase reporter and RNA pull-down assays were performed to verify the binding sites between LINC01224 and microRNA (miR)-485-5p and miR-485-5p and AKT3. LINC01224 expression was significantly upregulated in both EC tumor tissue and cell lines. The upregulation of LINC01224 was negatively associated with survival of patients with EC. Functionally, LINC01224 promoted proliferation and inhibited apoptosis of EC cells; LINC01224 directly bound to and downregulated miR-485-5p to elevate the expression levels of AKT3, thereby promoting EC progression. LINC01224 depletion in EC cells hindered tumor growth in a xenograft model. The tumor suppressing effect of LINC01224-knockdown on EC progression was partly rescued by treatment with miR-485-5p inhibitor. The present data demonstrated the expression levels, clinical relevance and functional mechanism of LINC01224 in EC. LINC01224 promoted EC development via sponging miR-485-5p to elevate AKT3 expression levels; this may provide a promising therapeutic target pathway for EC treatment.

Upregulation of circ_0000142 promotes multiple myeloma progression by adsorbing miR-610 and upregulating AKT3 expression

Circular RNAs (circRNAs) play an important regulatory role in a variety of malignancies. Nevertheless, the role of circ_0000142 in multiple myeloma (MM) and its regulatory mechanism remains largely unknown. Real-time polymerase chain reaction was employed to detect the expressions of circ_0000142 and miR-610 in MM tissues and cell lines. The expression of AKT3 and apoptosis-related proteins (Bcl-2, Bax) in MM cells was detected by western blot. The correlation between the expression level of circ_0000142 and the clinicopathological parameters of MM patients was analysed. Cell proliferation, apoptosis, migration and invasion were monitored by Cell Counting Kit 8 assay, flow cytometry analysis and Transwell assay, respectively. The dual-luciferase reporter gene assay and RNA immunoprecipitation assay were employed to verify the targeting relationship between circ_0000142 and miR-610. In this study, it was demonstrated that, circ_0000142 was highly expressed in MM patients, and its high expression level was significantly associated with increased International Staging System and Durie-Salmon stage. Overexpression of circ_0000142 enhanced MM cell proliferation, migration, invasion and suppressed cell apoptosis, while knocking down circ_0000142 had the opposite effects. Mechanistically, circ_0000142 functioned as a competitive endogenous RNA, directly targeting miR-610 and positively regulating AKT3 expression. In brief, circ_0000142 enhances the proliferation and metastasis of MM cells by modulating the miR-610/AKT3 axis.

LncRNA TP73-AS1 promotes oxidized low-density lipoprotein-induced apoptosis of endothelial cells in atherosclerosis by targeting the miR-654-3p/AKT3 axis

Background

Although lncRNA TP73-AS1 has been shown to play important roles in various human diseases, its function in atherosclerosis (AS) remains unclear.

Methods

Human aortic endothelial cells (HAECs) were treated with 50 μg/ml oxidized low-density lipoprotein (ox-LDL) to establish an atherosclerotic cell model. The expression of TP73-AS1, miR-654-3p and AKT3 was detected by qRT-PCR. Cell functions were evaluated CCK-8 assay and flow cytometry. The protein levels of apoptosis-related proteins were evaluated by western blot. The binding relationship among TP73-AS1, miR-654-3p and AKT3 was determined by bioinformatics analysis and luciferase reporter assay.

Results

TP73-AS1 was upregulated and miR-654-3p was downregulated in ox-LDL treated HAECs. TP73-AS1 silencing and miR-654-3p mimics decreased the viability and inhibited apoptosis of ox-LDL treated HAECs, decreased the expression levels of c-caspase-9, c-caspase-3 and Bax, and increased Bcl-2 expression. In addition, miR-654-3p inhibitor significantly reversed the inhibitory effects of si-TP73-AS1 on cell viability and apoptosis. TP73-AS1 could positively regulate AKT3 through directly sponging miR-654-3p.

Conclusion

TP73-AS1 promoted apoptosis of ox-LDL stimulated endothelial cells by targeting the miR-654-3p/AKT3 axis, suggesting that TP73-AS1 might be a potential target for AS treatment.

miR-150 and SRPK1 regulate AKT3 expression to participate in LPS-induced inflammatory response

miR-150 was found to target the 3'-untranslated regions of AKT3, and the AKT pathway was affected by SR protein kinase 1 (SRPK1). However, the expression and significance of miR-150, AKT3 and SRPK1 in acute lung injury (ALI) were not clear. Here, we found that the expression of miR-150 was significantly reduced, while the expression of AKT3 and SRPK1 were markedly increased in LPS-treated A549, THP-1 and RAW 264.7 cells. miR-150 significantly decreased levels of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α, reduced the expression of AKT3, but had no impact on SRPK1 expression compared with the control group in LPS-treated A549, THP-1 and RAW 264.7 cells. AKT3 silencing only reduced the production of pro-inflammatory cytokines and showed no effect on miR-150 and SRPK1 expression. Finally, we observed that miR-150 mimics and/or silencing of SRPK1 decreased the expression of AKT3 mRNA. Besides, over-expression of miR-150 or silencing of SRPK1 also reduced the expression of AKT3 protein, which exhibited the lowest level in the miR-150 mimics plus si-SRPK1 group. However, si-SRPK1 had no effect on miR-150 level. In conclusion, miR-150 and SRPK1 separately and cooperatively participate into inflammatory responses in ALI through regulating AKT3 pathway. Increased miR-150 and silenced SRPK1 may be a novel potential factor for preventing and treating more inflammatory lung diseases.

High glucose protects cardiomyocytes against ischaemia/reperfusion injury by suppressing myocardiocyte apoptosis via circHIPK3/miR-29b/AKT3 signalling

High glucose promoted expression of AKT3, a direct target gene of miR-29b, by regulating circHIPK3 that functioned as ceRNA to sponge and down-regulate miR-29b. As a potential target gene of miR-29b, AKT3 plays a crucial role in the pathogenesis of myocardial ischaemia/reperfusion (I/R) injury, and this study aimed to investigate the potential role of high glucose in the outcome of I/R injury. qPCR and luciferase assay were carried out to investigate the relationship between the expression of circHIPK3, miR-29b and ATK3 mRNA. Immunohistochemistry and TUNEL were performed to analyse the relationship between AKT3 expression and apoptosis of myocardiocytes in vivo. No obvious difference in myocardial functions was observed between I/R and control rats under hyperglycaemia (HG) and normal glucose (NG) conditions, except that the infarct size/area at risk (IS/AR) ratio and the amount of h-FABP expression were different under HG and NG conditions. The expression of circHIPK3 and ATK3 was significantly elevated in the rats preconditioned by NG, whereas the expression of miR-29a was remarkably decreased. Meanwhile, the apoptosis of myocardial tissue was reduced in the rats preconditioned by NG. Luciferase assay confirmed that miR-29a played a repressive role in the expression of circHIPK3 and ATK3. And subsequent study indicated that the over-expressed AKT3 could rescue the increased cell apoptosis rate induced by the knockdown of circHIPK3. In this study, we demonstrated that high glucose protects cardiomyocytes against I/R associated injury by suppressing apoptosis and high glucose promoted the expression of AKT3 by regulating the expression of circHIPK3/miR-29b.

CircRNA circTRAF3 promotes nasopharyngeal carcinoma metastasis through targeting miR-203a-3p/AKT3 axis

Distant metastasis is still the main cause of death in patients with nasopharyngeal carcinoma (NPC), and its mechanism is not fully understood. In this study, we studied the biological function and molecular mechanism of circular RNA circTRAF3 in NPC metastasis. We found that the increase in circTRAF3 is associated with the metastasis and survival of NPC patients. Knockdown of circTRAF3 could inhibit NPC cell proliferation and cell invasion, and induce apoptosis in vitro and in vivo. Further mechanism studies demonstrated that circTRAF3 eliminated the inhibitory effect of miR-203a-3p on AKT3 by adsorbing miR-203a-3p, and finally played the role of oncogene in NPC. Our findings reveal a new type of circRNA, circTRAF3, which acts as an oncogene in NPC and targets miR-203a-3p/AKT3 pathway. The circTRAF3/miR-203a-3p/AKT3 pathway may be a potential therapeutic target for metastatic NPC.

HNRNPA2B1 promotes multiple myeloma progression by increasing AKT3 expression via m6A-dependent stabilization of ILF3 mRNA

N6-methyladenosine (m6A) modification is the most prevalent modification in eukaryotic RNAs while accumulating studies suggest that m6A aberrant expression plays an important role in cancer. HNRNPA2B1 is a m6A reader which binds to nascent RNA and thus affects a perplexing array of RNA metabolism exquisitely. Despite unveiled facets that HNRNPA2B1 is deregulated in several tumors and facilitates tumor growth, a clear role of HNRNPA2B1 in multiple myeloma (MM) remains elusive. Herein, we analyzed the function and the regulatory mechanism of HNRNPA2B1 in MM. We found that HNRNPA2B1 was elevated in MM patients and negatively correlated with favorable prognosis. The depletion of HNRNPA2B1 in MM cells inhibited cell proliferation and induced apoptosis. On the contrary, the overexpression of HNRNPA2B1 promoted cell proliferation in vitro and in vivo. Mechanistic studies revealed that HNRNPA2B1 recognized the m6A sites of ILF3 and enhanced the stability of ILF3 mRNA transcripts, while AKT3 downregulation by siRNA abrogated the cellular proliferation induced by HNRNPA2B1 overexpression. Additionally, the expression of HNRNPA2B1, ILF3 and AKT3 was positively associated with each other in MM tissues tested by immunohistochemistry. In summary, our study highlights that HNRNPA2B1 potentially acts as a therapeutic target of MM through regulating AKT3 expression mediated by ILF3-dependent pattern.

LINC02163 promotes colorectal cancer progression via miR-511-3p/AKT3 axis

Long non-coding RNAs and microRNAs are functional regulators in tumour progression. Herein, we revealed the level LINC02163 was up-regulated in CRC tissues and cell lines, and the expression of LINC02163 negatively correlated with prognosis of CRC patients. Functional experiments demonstrated knockdown of LINC02163 significantly attenuated CRC cells proliferation and metastasis. Mechanism analysis showed miR-511-3p could bind LINC02163 and AKT3, and the expressional level of miR-511-3p negatively correlated with the abundance of LINC02163 and AKT3. Inhibition of LINC02163 suppressed cell proliferation, while transfection of miR-511-3p inhibitor or AKT3 in LINC02163-depletion cells restored cell growth and abolished the cell cycle arrest in G0/G1 phase. Therefore, it was indicated that LINC02163 exerted pro-tumour effect through miR-511-3p/AKT3 axis and was prognostic marker for colorectal cancer.

miR-485-3p regulated by MALAT1 inhibits osteosarcoma glycolysis and metastasis by directly suppressing c-MET and AKT3/mTOR signalling

AIMS

Osteosarcoma (OS) is an extremely malignant bone cancer with high incidence and rapid progression. This study aims to investigate the role and underlying mechanisms of MALAT1 and miR-485-3p in OS.

MATERIALS AND METHODS

qRT-PCR and Western blotting were utilized to measure the levels of miR-485-3p, MALAT1, c-MET, AKT3, p-mTOR, mTOR, glycolysis-related proteins or migration-related proteins. Colony formation and transwell assay were used to test the roles of miR-485-3p, MALAT1, c-MET and AKT3 in cancer cell proliferation, migration and invasion. Dual luciferase assay was used to validate the interactions of miR-485-3p/c-MET, miR-485-3p/AKT3, and MALAT1/miR-485-3p. Glucose uptake assay and measurement of lactate production were employed to determine the glycolysis process. Mouse tumour xenograft model was used to determine the effect of shMALAT1 and miR-485-3p mimics on tumour growth and metastasis in vivo.

KEY FINDINGS

miR-485-3p was decreased while c-MET, AKT3, and MALAT1 were increased in human OS tissues and cells. miR-485-3p bound directly to c-MET and AKT3 mRNAs and repressed OS cell glycolysis, proliferation, migration, and invasion through decreasing glycolysis-related proteins and migration-related proteins via inhibiting c-MET and AKT3/mTOR pathway. In addition, MALAT1 interacted with miR-485-3p and disinhibited c-MET and AKT3/mTOR signalling. Knockdown MALAT1 or overexpression of miR-485-3p restrained OS tumour growth and lung metastasis in vivo.

SIGNIFICANCE

miR-485-3p suppresses OS glycolysis, proliferation, and metastasis via inhibiting c-MET and AKT3/mTOR signalling and MALAT1 acts as a sponge of miR-485-3p. MALAT1 and miR-485-3p may be the key regulators in OS progression, and potential molecular targets for future OS therapy.

AKT3 Expression in Mesenchymal Colorectal Cancer Cells Drives Growth and Is Associated with Epithelial-Mesenchymal Transition

Simple Summary

Colorectal cancer can be subdivided into four distinct subtypes that are characterised by different clinical features and responses to therapies currently used in the clinic to treat this disease. One of those subtypes, called CMS4, is associated with a worse prognosis and poor response to therapies compared to other subtypes. We therefore set out to explore what proteins are differentially expressed and used in CMS4 to find potential new targets for therapy. We found that protein AKT3 is highly expressed in CMS4, and that active AKT3 inhibits a protein that stalls growth of cancer cells (p27^KIP1). We can target AKT3 with inhibitors which leads to strongly reduced growth of cancer cell lines that are categorised as CMS4. Furthermore, our data suggests that high AKT3 expression in tumour cells may be used to identify poor prognosis colorectal cancer patients. Future research should point out if high AKT3 expression can be used to select colorectal cancer patients that have a poor prognosis but that could benefit from AKT3-targeted treatment.

Abstract

Colorectal cancer (CRC) is a heterogeneous disease that can currently be subdivided into four distinct consensus molecular subtypes (CMS) based on gene expression profiling. The CMS4 subtype is marked by high expression of mesenchymal genes and is associated with a worse overall prognosis compared to other CMSs. Importantly, this subtype responds poorly to the standard therapies currently used to treat CRC. We set out to explore what regulatory signalling networks underlie the CMS4 phenotype of cancer cells, specifically, by analysing which kinases were more highly expressed in this subtype compared to others. We found AKT3 to be expressed in the cancer cell epithelium of CRC specimens, patient derived xenograft (PDX) models and in (primary) cell cultures representing CMS4. Importantly, chemical inhibition or knockout of this gene hampers outgrowth of this subtype, as AKT3 controls expression of the cell cycle regulator p27^KIP1. Furthermore, high AKT3 expression was associated with high expression of epithelial-mesenchymal transition (EMT) genes, and this observation could be expanded to cell lines representing other carcinoma types. More importantly, this association allowed for the identification of CRC patients with a high propensity to metastasise and an associated poor prognosis. High AKT3 expression in the tumour epithelial compartment may thus be used as a surrogate marker for EMT and may allow for a selection of CRC patients that could benefit from AKT3-targeted therapy.