ARNTL inhibits the malignant behaviors of oral cancer by regulating autophagy in an AKT/mTOR pathway-dependent manner

IGF2BP3-regulated circPLEKHH2 promotes autophagy via AKT/mTOR signaling pathway to suppress lung adenocarcinoma progression

Lung adenocarcinoma (LUAD) is the most common malignant tumor in the lung. Circular RNAs (circRNAs) play critical roles in cancer progression. However, the functions and mechanisms of circPLEKHH2 in regulating cancer progression and autophagy in LUAD are largely unknown. Our research team identified circPLEKHH2 (annotated as hsa_circ_0120106) which is significantly down-regulated in LUAD via RNA-seq in 14 pairs of LUAD tissues. The expression level of circPLEKHH2 in patient tissue has potential diagnostic value to distinguish LUAD tissue from normal lung tissue. Functionally, circPLEKHH2 promoted autophagy and inhibited LUAD cell prolifera-tion, invasion, migration, and tumor growth. Mechanistically, we identified that circPLEKHH2 promoted autophagy via the AKT/mTOR signaling pathway, and the mTOR inhibitor rapamycin can reverse the oncogenic effects of circPLEKHH2 silencing. IGF2BP3 can bind to circPLEKHH2 to inhibit its expression. These results revealed that as a tumor suppressor, IGF2BP3-regulated circPLEKHH2 promotes autophagy through the AKT/mTOR signaling pathway to inhibit the occurrence and progression of LUAD. Therefore, circPLEKHH2 could be a potential therapeutic target for LUAD.

ATG9B-4 accelerates the proliferation and migration of liver cancer cells in an ARNTL-CDK5 pathway-dependent manner: A case-control study

Lnc ATG9B-4 aggravated the progression of liver cancer by up-regulating cyclin-dependent-kinase 5 (CDK5). It could be inferred that ATG9B-4 indirectly regulates the expression of CDK5 via lncRNA-mediated negative regulation of target genes. Therefore, the specific molecular mechanism by which ATG9B-4 regulates the malignant characteristics of liver cancer cells still needs further study. The differentially expressed genes were identified by mRNA sequencing in liver cancer cells transfected with or without ATG9B-4. Liver cancer cells were transfected with ATG9B-4, ARNTL, or si-CDK5. The expression of aryl basic helix-loop-helix ARNT like 1 (BMAL1, also known as ARNTL), CDK5, and ATG9B-4 was analyzed by real-time quantitative PCR and western blotting. The proliferation and invasion of the transfected cells were respectively analyzed by cell counting kit-8 and wound healing assays, respectively. The ARNTL expression was down-regulated in the liver cancer tissues and liver cancer cells transfected with ATG9B-4. Low ARNTL expression indicated poor overall survival in patients with liver cancer. The optical density of cells transfected with ATG9B-4 and ARNTL was significantly lower than that of cells transfected with ATG9B-4. The wound areas of cells transfected with ATG9B-4 and ARNTL were markedly wider than those of cells transfected with ATG9B-4. The expression of CDK5 was down-regulated in cells transfected with ARNTL. CDK5 knockdown partially attenuated the ATG9B-4-induced increase in proliferation and migration in liver cancer cells. ATG9B-4 deteriorated the proliferation and migration of liver cancer cells in an ARNTL-CDK5 pathway-dependent manner.

Identification and validation of autophagy-related genes influenced by paris polyphylla in tongue cancer using network pharmacology

BACKGROUND

Tongue squamous cell carcinoma (TSCC) represents the most prevalent form of head and neck squamous cell carcinomas, comprising approximately one-third of all oral cancers. Paris polyphylla(PP) exhibit promising anti-tumor properties, yet their underlying mechanisms remain elusive. This study offers novel insights into the molecular mechanisms underlying TSCC treatment with PP and establishes a theoretical basis for their clinical application.

METHODS

Employing transcriptomics and network pharmacology methodologies, we identified autophagy-related key genes associated with the effects of PP. These genes were subjected to KEGG and GO enrichment analyses to determine their related functions. In vitro, CAL-27 cells were treated with 10, 30, and 60 μg/ml of PP for 24 h to assess tumor cell proliferation, apoptosis, and autophagy-related markers.

KEY FINDINGS

Molecular docking of MAPK3 and PSEN1 with PP revealed stable hydrogen bond interactions, indicating the therapeutic potential of these saponins in TSCC through the autophagy pathway. In vitro experiments demonstrated significant inhibition of proliferative activity in tongue squamous carcinoma CAL-27 cells and promotion of tumor cell apoptosis by PP. Western blot analysis confirmed alterations in the expression of autophagy markers P62, LC3B, and Beclin1 following treatment, suggesting activation of the autophagy pathway.

CONCLUSIONS

Our results suggest that PP inhibits tumor cells through the autophagy pathway, in which MAPK3 and PSEN1 play a role as potential functional molecules.

The interplay between the PI3K/AKT pathway and circadian clock in physiologic and cancer-related pathologic conditions

The circadian clock is responsible for the regulation of different cellular processes, and its disturbance has been linked to the development of different diseases, such as cancer. The main molecular mechanism for this issue has been linked to the crosstalk between core clock regulators and intracellular pathways responsible for cell survival. The PI3K/AKT signalling pathway is one of the most known intracellular pathways in the case of cancer initiation and progression. This pathway regulates different aspects of cell survival including proliferation, apoptosis, metabolism, and response to environmental stimuli. Accumulating evidence indicates that there is a link between the PI3K/AKT pathway activity and circadian rhythm in physiologic and cancer-related pathogenesis. Different classes of PI3Ks and AKT isoforms are involved in regulating circadian clock components in a transcriptional and functional manner. Reversely, core clock components induce a rhythmic fashion in PI3K and AKT activity in physiologic and pathogenic conditions. The aim of this review is to re-examine the interplay between this pathway and circadian clock components in normal condition and cancer pathogenesis, which provides a better understanding of how circadian rhythms may be involved in cancer progression.

Akt/mTOR Pathway Agonist SC79 Inhibits Autophagy and Apoptosis of Oligodendrocyte Precursor Cells Associated with Neonatal White Matter Dysplasia

White matter dysplasia (WMD) in preterm infants due to intrauterine inflammation is caused by excessive apoptosis of oligodendrocyte precursor cells (OPCs). In recent years, studies have found that excessive autophagy and apoptosis are highly interconnected and important in infection and inflammatory diseases in general. Therefore, in this study, we aimed to confirm whether regulation of autophagy by using the Akt phosphorylation agonist SC79 can inhibit abnormal apoptosis of OPCs and promote myelin maturation and white matter development in neonatal rats with WMD. We investigated the effect of inflammation on oligodendrocyte development in P0 neonatal rats by intracerebellar injection of LPS, and collected brain tissue at P2 and P5. Immunohistochemical and immunofluorescence staining were used to evaluate white matter damage, while immunofluorescence staining, terminal deoxynucleotidyl transferase dUTP nick end labeling analysis (TUNEL), and western blotting were used to evaluate autophagy and apoptosis. First, we observed that white matter development was arrested and white matter fiber maturation was impaired in LPS-inflicted pups compared with those in the sham-operated group. Second, treatment with SC79 reduced the levels of LC3II, caspase 3, caspase 9, and Bax/Bcl-2 and increased the levels of p62, p-Akt, and p-mTOR in the brain tissue of neonatal rats. Finally, SC79 treatment inhibited OPC apoptosis by increasing the binding of Beclin 1 to Bcl-2, which promoted OPC differentiation and maturation. However, the opposite results were observed after rapamycin administration. Taken together, our results suggest that SC79 can inhibit the abnormal apoptosis of OPCs caused by excessive autophagy through the Akt/mTOR pathway and that SC79 is a potential therapeutic agent for WMD in preterm infants.