Project description:MicroRNA-34a (miR-34a) plays an essential role against tumorigenesis and progression of cancer metastasis. Here, we analyzed the expression, targets and functional effects of miR-34a on epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs), such as TWIST1, SLUG and ZEB1/2, and an EMT-inducing protein NOTCH1 in breast cancer (BC) cell migration and invasion and its correlation with tumorigenesis and clinical outcomes. Expression of miR-34a is downregulated in human metastatic breast cancers (MBC) compared to normal breast tissues and is negatively correlated with clinicopathological features of MBC patients. Ectopic expression of miR-34a in MBC cell-line BT-549 significantly inhibits cell migration and invasion, but exhibits no clear effect on BC cell growth. We found that miR-34a is able to inactivate EMT signaling pathway with mediatory of NOTCH1, TWIST1, and ZEB1 upon 3'-UTR activity in MBC cell lines, but has no inhibitory effects on SLUG and ZEB2. Furthermore, we investigated the synergistic effects of Thymoquinone (TQ) and miR-34a together on the expression of EMT-associated proteins. Results showed that co-delivery of miR-34a and TQ is able to inactivate EMT signaling pathway by directly targeting TWIST1 and ZEB1 in BT-549 cell line, indicating that they might be a promising therapeutic combination against breast cancer metastasis. Epigenetic inactivation of the EMT-TFs/miR-34a pathway can potentially alter the equilibrium of these regulations, facilitating EMT and metastasis in BC. Altogether, our findings suggest that miR-34a alone could serve as a potential therapeutic agent for MBC, and together with TQ, their therapeutic potential is synergistically enhanced.
Project description:Cell migration and invasion are highly regulated processes involved in both physiological and pathological conditions. Here we show that autophagy modulation regulates the migration and invasion capabilities of glioblastoma (GBM) cells. We observed that during autophagy occurrence, obtained by nutrient deprivation or by pharmacological inhibition of the mTOR complexes, GBM migration and chemokine-mediated invasion were both impaired. We also observed that SNAIL and SLUG, two master regulators of the epithelial-mesenchymal transition (EMT process), were down-regulated upon autophagy stimulation and, as a consequence, we found a transcriptional and translational up-regulation of N- and R-cadherins. Conversely, in BECLIN 1-silenced GBM cells, an increased migration capability and an up-regulation of SNAIL and SLUG was observed, with a resulting decrease in N- and R-cadherin mRNAs. ATG5 and ATG7 down-regulation also resulted in an increased migration and invasion of GBM cells combined to an up-regulation of the two EMT regulators. Finally, experiments performed in primary GBM cells from patients largely confirmed the results obtained in established cell cultures. Overall, our results indicate that autophagy modulation triggers a molecular switch from a mesenchymal phenotype to an epithelial-like one in GBM cellular models. Since the aggressiveness and lethality of GBM is defined by local invasion and resistance to chemotherapy, we believe that our evidence provides a further rationale for including autophagy/mTOR-based targets in the current therapeutical regimen of GBM patients.
Project description:BackgroundStudying the mechanism of action of LncRNAs in lung adenocarcinoma (LUAD) is of great importance for an in-depth understanding of the molecular mechanism of lung adeno carcinogenesis and development.ObjectiveThe aim is to identify a long non-coding RNA LINC01117 that is specifically and highly expressed in LUAD cells and to investigate its biological functions and molecular mechanisms in LUAD cells, providing a new potential target for targeting LUAD therapy.MethodsThis study used publicly available data downloaded from The Cancer Genome Atlas (TCGA) database. Construction of siRNA and overexpression plasmid-packed lentiviral constructs were used to knock down and increase the expression of LINC01117 in LUAD cells. The effect of LINC01117 on LUAD cell migration and invasion was verified by scratch assays and Transwell assays. Western blot assays were performed to verify the effect of knocking down LINC01117 expression on key proteins of the EMT process. The effect of overexpression and knockdown LINC01117 expression on key proteins of the EMT process and the nuclear and cytoplasmic distribution of YAP1, a key effector molecule of the Hippo pathway, was verified by Western blot assays.ResultsLINC01117 expression was upregulated in LUAD tissues and cell lines. Clinical correlation and prognostic analyses showed that LINC01117 was associated with poorer clinical features (staging and N classification) and poorer prognosis and could be analyzed as an independent prognostic factor. Cell migration and invasion were significantly inhibited in the knockdown group compared to the control group; in contrast, cell migration and invasion were promoted in the overexpression group. Overexpression of LINC01117 resulted in down-regulation of E-cadherin expression and increased expression levels of N-cadherin, vimentin, ZEB1, snail and slug; in contrast, knockdown of LINC01117 appeared to have the opposite effect. Furthermore, knockdown of LINC01117 increased the enrichment of YAP1 protein in the cytoplasm and reduced its level in the nucleus; overexpression of LINC01117 produced the opposite intracellular distribution results.ConclusionsLINC01117 was highly expressed in LUAD, and knockdown of LINC01117 significantly inhibited the migration and invasion of LUAD cells, while overexpression of LINC01117 significantly promoted the migration and invasion of LUAD cells, and affected the EMT process, and was able to alter the distribution of YAP1 in the nucleus and cytoplasm. This suggests that LINC01117 may regulate the activity of the Hippo pathway by altering the nuclear and cytoplasmic distribution of YAP1, which in turn induces the EMT process in lung adenocarcinoma cells and thus exerts a pro-cancer effect. It suggests that LINC01117 may play a key role in the occurrence and development of LUAD.
Project description:Hepatocellular carcinoma is the seventh most common type of cancer in the world, with limited treatment options. A promising strategy to treat cancer is to associate chemotherapeutics and plant bioactive compounds. Here, we examined whether diallyl disulfide (DADS; 50-200 μM) and sorafenib (SORA; 8 μM), either alone or in combination, were toxic to hepatocellular carcinoma cells (HepG2) in vitro. We assessed whether DADS and/or SORA induced cell death (LIVE/DEAD assay and autophagy) and cell cycle changes (flow cytometry), altered expression of key genes and proteins (RT-qPCR and Western blot), and modulated tumorigenesis signatures, such as proliferation (clonogenic assay), migration (wound healing), and invasion (inserts). The DADS + SORA combination elicited autophagic cell death by upregulating LC3 and NRF2 expression and downregulating FOS and TNF expression; induced the accumulation of cells in the G1 phase which thereby upregulated the CHEK2 expression; and inhibited invasion by downregulating the MMP2 expression. Predictive analysis indicated the participation of the MAPK pathway in the reported results. The DADS + SORA combination suppressed both cell invasion and clonogenic survival, which indicated that it dampened tumor growth, proliferation, invasion, and metastatic potential. Therefore, the DADS + SORA combination is a promising therapy to develop new clinical protocols.
Project description:Esophageal cancer (EC) is a complex gastrointestinal malignancy and its global incidence rate ranks 7th among all cancer types. Due to its aggressive nature and the potential for early metastasis, the survival rates of patients with EC are poor. Dihydroartemisinin (DHA) is the primary active derivative of artemisinin, and, as well as its use as an anti-malarial, DHA has also exhibited antitumor activity in various cancer models, such as cholangiocarcinoma, head and neck carcinoma, and hepatocellular carcinoma cells. However, the molecular mechanisms underlying the antitumor effect of DHA in the treatment of EC remains poorly understood. The results of the present study demonstrated that DHA significantly inhibited the migration of TE-1 and Eca-109 EC cells in a dose-dependent manner by activating autophagy. DHA treatment also significantly reversed epithelial-mesenchymal transition (EMT) by downregulating the EMT-associated markers, N-cadherin and vimentin, and upregulating the expression of E-cadherin. Mechanistically, DHA treatment decreased Akt phosphorylation and inhibited the Akt/mTOR signaling pathway, leading to the activation of autophagy. The levels of the autophagy-associated proteins were suppressed and DHA-mediated inhibition of migration in EC cells was reversed when an active form of Akt was overexpressed. In conclusion, the present study demonstrated the potential value of DHA in the treatment of EC, and revealed the underlying mechanism by which FDHA inhibits cellular migration.
Project description:OBJECTIVE:To investigate the effect of Aurora kinase B (AURKB) silencing-induced autophagy on apoptosis of osteosarcoma 143B cells and the underlying molecular mechanisms. METHODS:Human osteosarcoma 143B cells were transfected with Lv/shAURKB or the negative control vector Lv/shScrambled followed by treatment with chloroquine (CQ) for 24 h. Western blotting was performed to detect the protein expression levels of AURKB, P62, LC3, cleaved caspase-3, Bcl-2, and P-ULK1Ser555. Transmission electron microscopy and LC3 dual-label fluorescence method were used to trace the autophagosomes in 143B cells to assess cell autophagy, and the cell apoptosis was detected using flow cytometry and TUNEL assay. Co-immunoprecipitation assay was used to detect the interaction between AURKB and ULK1. RESULTS:The ratio of autophagy-related proteins LC3 II/I and the number of autophagosomes were significantly increased in 143B cells after transfection with Lv/shAURKB (P < 0.05), which significantly increased the expression of cleaved caspase-3 and reduced the expression of Bcl-2 (P < 0.05). Combined treatment of the cells with Lv/shAURKB and the autophagy inhibitor chloroquine obviously restored the expressions of caspase-3 and Bcl-2 (P < 0.05). Transfection with Lv/shAURKB significantly increased the apoptosis rate of 143B cells (P < 0.05), and this effect was significantly antagonized by combined treatment with chloroquine (P < 0.05). AURKB silencing strongly activated the phosphorylation of the autophagy-initiating protein ULK1Ser555 in 143B cells (P < 0.05). The results of co-immunoprecipitation assay confirmed when AURKB was immunoprecipitated, ULK1 also precipitated. CONCLUSIONS:Silencing AURKB can induce autophagy by activating ULK1Ser555 phosphorylation to promote apoptosis in 143B cells.
Project description:Despite advances in therapeutic approaches, the five-year survival rate for head and neck squamous cell carcinoma (HNSCC) patients is still less than fifty percent. Research has indicated that the consumption of Allium vegetables or processed garlic containing diallyl trisulfide (DATS) can lower the risk of multiple types of cancer. Nevertheless, the effectiveness and underlying mechanisms of DATS against HNSCC have not been thoroughly explored until the current study. In this research, it was found that DATS notably curtailed the growth and viability of HNSCC cells. Additionally, DATS triggered a significant G2/M cell cycle arrest in these cells, accumulating cyclin B1, Cip1/p21, and Ser-10 phospho-histone H3-this was indicative of mitotic arrest attenuated by NAC pretreatment, suggesting the role of reactive oxygen species (ROS) induction. The production of ROS induced by DATS led to DNA damage and apoptosis, a process associated with elevated levels of cleaved caspase-3 and cleaved PARP, along with reduced XIAP. When HNSCC cells were exposed to pharmacological concentrations of DATS, it resulted in the suppression of cancer stem cell (CSC) populations, as indicated by a decrease in the CD133high/CD44high cell fraction, reduced aldehyde dehydrogenase 1 (ALDH1) activity, inhibited spheroid formation and downregulated SOX2 and Oct4 expression. Furthermore, the administration of DATS to tumor xenografts demonstrated its in vivo capacity to hinder CSCs. Further, DATS treatment inhibited the growth of UMSCC-22B head and neck cancer tumor xenograft in immunocompromised mice. Overall, DATS inhibited cell proliferation; induced cell cycle mitotic arrest and apoptosis involving DNA damage through ROS generation; reduced the CSC fraction and spheroid formation; and downregulated SOX2 and Oct4 expression. More importantly, DATS inhibited HNSCC tumor growth and CSC fraction in vivo. Thus, DATS could be a potential anticancer agent that can be used against head and neck cancer.
Project description:Vascular cell adhesion molecular 1 (VCAM1), an important member of the immunoglobulin superfamily, is related to the development of malignant tumors, such as breast cancer, melanoma, and renal clear cell carcinoma. However, the molecular role and mechanism of VCAM1 in the regulation of the progression of colorectal cancer (CRC) has rarely been studied. The results of IHC and RT-PCR analyses proved that VCAM1 was upregulated in human CRC tissues compared with matched adjacent normal intestinal epithelial tissues. Moreover, analysis of data from the TCGA and Gene Expression Omnibus (GEO) databases revealed that a higher level of VCAM1 was strongly correlated with poor differentiation, metastasis, and short survival in CRC patients. Furthermore, VCAM1 significantly influenced the invasion and metastasis of CRC cells in vitro and in vivo and activated the EMT program, by which cancer cells adhere to the endothelium and cross the vessel wall by forming pseudopodia and invadopodia. The current findings demonstrate that VCAM1 promotes tumor progression in CRC.
Project description:Potato late blight, caused by Phytophthora infestans, leads to a significant reduction in the yield and value of potato. Biocontrol displays great potential in the suppression of plant diseases. Diallyl trisulfide (DATS) is a well-known natural compound for biocontrol, although there is little information about it against potato late blight. In this study, DATS was found to be able to inhibit the hyphae growth of P. infestans, reduce its pathogenicity on detached potato leaves and tubers, and induce the overall resistance of potato tubers. DATS significantly increases catalase (CAT) activity of potato tubers, and it does not affect the levels of peroxidase (POD), superoxide dismutase (SOD), and malondialdehyde (MDA). The transcriptome datasets show that totals of 607 and 60 significantly differentially expressed genes (DEGs) and miRNAs (DEMs) are detected. Twenty-one negatively regulated miRNA-mRNA interaction pairs are observed in the co-expression regulatory network, which are mainly enriched in metabolic pathways, biosynthesis of secondary metabolites, and starch and sucrose metabolism based on the KEGG pathway. Our observations provide new insight into the role of DATS in biocontrol of potato late blight.
Project description:The multiterritory perforator flap is one of the widest flap patterns used to repair tissue defects. However, flap necrosis of the distal part is still a challenging issue for plastic surgeons. Diallyl trisulfide (DATS) is an efficient ingredient extracted from garlic, exerting many important effects on different diseases. Our experiment aims to reveal whether DATS has a beneficial effect on the survival of perforator flaps and to explore its mechanism of action. The results showed that DATS enhanced angiogenesis and autophagy and reduced cell apoptosis and oxidative stress, thereby improving the survival rate of skin flaps. After co-administration with autophagy inhibitor 3-methyladenine (3MA), perforator flap survival was further improved. Mechanistically, we showed that PI3K/Akt and AMPK-HIF-1α signaling pathways in flap were activated under DATS treatment. All in all, DATS promoted the survival of multiterritory perforator flaps via the synergistic regulation of PI3K/Akt and AMPK-HIF-1α signaling pathways, and inhibition of DATS-induced autophagy further improves flap survival.