Inhibition of PI3K/Akt/mTOR pathway by apigenin induces apoptosis and autophagy in hepatocellular carcinoma cells

Characterization of the antioxidative polysaccharides from Ziziphus jujube cv. Goutouzao and its tumor-inhibitory effects on human colorectal carcinoma LoVo cells via immunocyte activation

Colorectal cancer, the most common malignancy in Asian and west world, is listed as the fourth lethal neoplastic disease with increasing incidence worldwide. Recently, Ziziphus jujube were reported with hepatoprotective, antihypertensive, and hypoglycemic functions. The polysaccharides from Ziziphus jujube was considered as the main component for these bioactivities. In this study, polysaccharides from Ziziphus jujube cv. Goutouzao (GZSP) was comprehensively investigated, and characterized as a heteropolysaccharide with antioxidant activity. Besides, it can stimulate the viability of immune cells RAW 264.7, which in turn inhibited the proliferation of colorectal carcinoma cells (LoVo) by inducing apoptosis, arresting cell cycle in G0/G1, and increasing intracellular ROS, as demonstrated by Flow Cytometric analyses. The results suggest that, different from chemotherapeutic modalities, GZSP can exert antitumor effects by activating immune reaction, providing more evidence for the development of GZSP-based functional foods and anticancer drugs serving as human colon cancer prevention. PRACTICAL APPLICATIONS: Natural products from medicinal and edible plant are great sources of phytochemicals beneficial to human health, such as tea polyphenols, carotenoids, and phytosterols, etc. In this study, GZSP, the polysaccharides from a well-received fruit, Ziziphus jujube cv. Goutouzao, has been comprehensively investigated. The results show that GZSP fights against free radicals commonly found in human circulation, a property that enables it to be used as an antioxidant food additive with jujube flavor. More importantly, GZSP impedes neoplastic progression by activating immune response, as evidenced by the inhibition of colorectal carcinoma (LoVo) cells. Comparing with chemotherapies usually imposing cytotoxicity on normal tissues, natural product GZSP is able to exert the antiproliferative effects on carcinoma cells with minimal side-effects. Therefore, GZSP-based functional foods and anticancer drugs with the purpose of preventing human colon cancer formation are promising to be developed.

Recent Advances in Characterizing Natural Products that Regulate Autophagy

Autophagy, an intricate response to nutrient deprivation, pathogen infection, Endoplasmic Reticulum (ER)-stress and drugs, is crucial for the homeostatic maintenance in living cells. This highly regulated, multistep process has been involved in several diseases including cardiovascular and neurodegenerative diseases, especially in cancer. It can function as either a promoter or a suppressor in cancer, which underlines the potential utility as a therapeutic target. In recent years, increasing evidence has suggested that many natural products could modulate autophagy through diverse signaling pathways, either inducing or inhibiting. In this review, we briefly introduce autophagy and systematically describe several classes of natural products that implicated autophagy modulation. These compounds are of great interest for their potential activity against many types of cancer, such as ovarian, breast, cervical, pancreatic, and so on, hoping to provide valuable information for the development of cancer treatments based on autophagy.

Polyphenol-Mediated Autophagy in Cancer: Evidence of In Vitro and In Vivo Studies

One of the hallmarks of cellular transformation is the altered mechanism of cell death. There are three main types of cell death, characterized by different morphological and biochemical features, namely apoptosis (type I), autophagic cell death (type II) and necrosis (type III). Autophagy, or self-eating, is a tightly regulated process involved in stress responses, and it is a lysosomal degradation process. The role of autophagy in cancer is controversial and has been associated with both the induction and the inhibition of tumor growth. Autophagy can exert tumor suppression through the degradation of oncogenic proteins, suppression of inflammation, chronic tissue damage and ultimately by preventing mutations and genetic instability. On the other hand, tumor cells activate autophagy for survival in cellular stress conditions. Thus, autophagy modulation could represent a promising therapeutic strategy for cancer. Several studies have shown that polyphenols, natural compounds found in foods and beverages of plant origin, can efficiently modulate autophagy in several types of cancer. In this review, we summarize the current knowledge on the effects of polyphenols on autophagy, highlighting the conceptual benefits or drawbacks and subtle cell-specific effects of polyphenols for envisioning future therapies employing polyphenols as chemoadjuvants.

ERCC6L promotes the progression of hepatocellular carcinoma through activating PI3K/AKT and NF-κB signaling pathway

Background

Excision Repair Cross-Complementation group 6-like (ERCC6L) has been shown to exhibit carcinogenic effect in several malignant tumors. However, the function and molecular mechanism of the ERCC6L in hepatocellular carcinoma (HCC) have not been investigated extensively.

Methods

Immunohistochemistry analyses were used to detect ERCC6L expression in a HCC tissue microarray, and the Chi-square test was used to assess the correlation between ERCC6L expression and patients’ clinicopathological features. shRNA was used to down-regulation ERCC6L expression in HCC cell lines. MTT assay, plate clone formation assay, flow cytometry, caspase 3/7 activity and migration assays were performed to evaluate the impact of ERCC6L on HCC cells in vitro. Nude mice xenograft models were used to assess the role of ERCC6L in vivo. The regulatory of mechanism of PI3K/AKT pathway was evaluated by western blotting.

Results

ERCC6L was highly expressed in HCC tissue compared with tumor adjacent tissues in 90 paired samples. ERCC6L expression positively correlated with gender, tumor encapsulation, and pathological stage. Patients with low ERCC6L expression had significantly longer OS than those with high ERCC6L expression. Knockdown of ERCC6L expression significantly inhibited proliferation, invasion and metastasis in vitro and tumor growth in vivo, and it promoted cell cycle arrest and apoptosis. Mechanistic analyses revealed that PI3K/AKT and NF-κB signaling pathway were inhibited by silencing ERCC6L.

Conclusion

These results demonstrate that ERCC6L plays a critical role in HCC progression, and thereby might be a potential therapeutic target for HCC patients.

Dihydroartemisinin inhibits the migration of esophageal cancer cells by inducing autophagy

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.

Lidocaine promotes autophagy of SH-SY5Y cells through inhibiting PI3K/AKT/mTOR pathway by upregulating miR-145

Lidocaine is one of the most common local anesthetics (LA) used in clinical practice and it is neurotoxic. Recent studies suggested that LA, including lidocaine, could exert protective effect over neurotoxicity by promoting autophagy. However, the underlying mechanism was not sufficiently elucidated. This study aimed to explore the mechanism behind. Human neuroblastoma cell line SH-SY5Y was used throughout the whole study. The effect of lidocaine on viability, toxicity of SH-SY5Y cells were analyzed by MTT and lactate dehydrogenase (LDH) assays, respectively. The relative expression of miR-145 was assessed by quantitative reverse transcription-polymerase chain reaction. The impact which lidocaine brought on PI3K/AKT/mTOR pathway and autophagy-related proteins were examined by the western blot assay. LC3B was assessed by immunofluorescence staining. The interaction between miR-145 and AKT3 was conducted by the dual-luciferase reporting assay. Lidocaine inhibited viability of SH-SY5Y cells in a time and dose dependent manner and enhanced the release of LDH in SH-SY5Y cells. Furthermore, the expression of miR-145 and autophagy were enhanced by lidocaine. Transfection with miR-145 inhibitor inhibited the release of LDH and autophagy. miR-145 targeted AKT3 to inhibit PI3K/AKT/mTOR pathway. Finally, lidocaine inactivated PI3K/AKT/mTOR pathways via upregulation of miR-145, and it subsequently promoted autophagy of SH-SY5Y cells. However, silence of miR-145 could reverse the promotion of the autophagy of SH-SY5Y cells. Our results showed that lidocaine promoted autophagy of nerve cells via regulating miR-145 expression and further inactivation of PI3K/AKT/mTOR signaling pathway.

Paecilomyces cicadae-fermented Radix astragali activates podocyte autophagy by attenuating PI3K/AKT/mTOR pathways to protect against diabetic nephropathy in mice

Radix astragali, a medicinal material for tonifying Chinese Qi, has widely been used for the treatment of Kidney disease in China and East Asia, especially in reducing the apoptosis of glomerular podocytes. Paecilomyces Cicadidae is a medicinal and edible fungus. In recent years, the application of traditional Chinese medicine (TCM) in solid-state fermentation of edible and medicinal fungi has become a hot issue. Fermentation is a special method to change the properties of TCM. Therefore, the potential roles and molecular mechanisms on podocytes of solid-state fermentation products of Radix astragali and Paecilomyces cicadidae (RPF) in diabetic nephropathy (DN) were studied. In vivo, the effect of RPF and Radix astragali on DN in mice was evaluated by detecting the biochemical indexes of blood and urine, renal function and podocyte integrity. In vitro, the expression of podocyte marker protein, autophagy marker protein and PI3K/AKT/mTOR signaling pathway protein were detected by Western blotting using a high glucose-induced podocyte injury model. The results showed that RPF had a significant alleviative effect on DN mice. RPF can significantly reduce urine protein, serum creatinine, and blood nitrogen urea in DN mice. Morphological analysis showed that RPF could improve kidney structure of DN and reduce the apoptosis of podocytes, and the effect was better than Radix astragali. In vitro results indicated that RPF could enhance autophagy and protect podocytes by inhibiting the PI3K/AKT/mTOR signaling pathway. In summary, RPF has better effect on delaying the development of DN than Radix astragali. RPF enhances autophagy in podocytes and delays DN probably by inhibiting the PI3K/AKT/mTOR signaling pathway.

Targeting apoptosis and autophagy following spinal cord injury: Therapeutic approaches to polyphenols and candidate phytochemicals

Spinal cord injury (SCI) is a neurological disorder associated with the loss of sensory and motor function. Understanding the precise dysregulated signaling pathways, especially apoptosis and autophagy following SCI, is of vital importance in developing innovative therapeutic targets and treatments. The present study lies in the fact that it reveals the precise dysregulated signaling mediators of apoptotic and autophagic pathways following SCI and also examines the effects of polyphenols and other candidate phytochemicals. It provides new insights to develop new treatments for post-SCI complications. Accordingly, a comprehensive review was conducted using electronic databases including, Scopus, Web of Science, PubMed, and Medline, along with the authors' expertise in apoptosis and autophagy as well as their knowledge about the effects of polyphenols and other phytochemicals on SCI pathogenesis. The primary mechanical injury to spinal cord is followed by a secondary cascade of apoptosis and autophagy that play critical roles during SCI. In terms of pharmacological mechanisms, caspases, Bax/Bcl-2, TNF-α, and JAK/STAT in apoptosis along with LC3 and Beclin-1 in autophagy have shown a close interconnection with the inflammatory pathways mainly glutamatergic, PI3K/Akt/mTOR, ERK/MAPK, and other cross-linked mediators. Besides, apoptotic pathways have been shown to regulate autophagy mediators and vice versa. Prevailing evidence has highlighted the importance of modulating these signaling mediators/pathways by polyphenols and other candidate phytochemicals post-SCI. The present review provides dysregulated signaling mediators and therapeutic targets of apoptotic and autophagic pathways following SCI, focusing on the modulatory effects of polyphenols and other potential phytochemical candidates.

Long non-coding RNA HAGLROS regulates lipid metabolism reprogramming in intrahepatic cholangiocarcinoma via the mTOR signaling pathway

Alternation of long non-coding RNA (lncRNA) is implicated in intrahepatic cholangiocarcinoma (ICC) development. HAGLROS is a lncRNA with a length of 699 bp, which is involved in the progression of various cancers. But the mechanism of HAGLROS in ICC remains unknown. In this study, the sh-HAGLROS-1 or sh-HAGLROS-2 was transfected into QBC939 cells, and overexpressing HAGLROS vector was transfected into KMCH cells. HAGLROS expression in ICC tissues and cell lines was detected, and its association with ICC prognosis was further analyzed. Lipid accumulation and lipid-related indicators (TG, LDL-C, TC and HDLC) in QBC939 and KMCH cells were measured. ICC cell viability, invasion and migration were measured. Western blot analysis was used to detect levels of the mTOR axis-related proteins and autophagy-related proteins (LC3I, LC3II, Beclin and P62). The levels of serum lipids and SREBP1 positive expression in transplanted tumors of nude mice were detected. HAGLROS was highly expressed in ICC and negatively correlated with prognosis. QBC939 cells with knocking down HAGLROS exhibited reduced lipid-related protein levels, blocked ICC cellular processes, inactivated mTOR axis, and increased autophagy. QBC939 cells with overexpressing HAGLROS showed opposite trends. The lipid-related protein levels in serum of nude mice and SREBP1 positive expression in transplanted tumors were diminished. Taken together, sh-HAGLROS inactivated the mTOR axis and promoted autophagy, thereby improving lipid metabolism reprogramming in ICC. This study may offer novel ICC treatments.

Effect of Oleanolic Acid on Apoptosis and Autophagy of SMMC-7721 Hepatoma Cells

BACKGROUND Liver cancer is a common cancer with high morbidity and mortality. Due to the large toxic side effects of chemotherapeutic drugs and the overexpression of multidrug resistance genes in liver cancer, no effective chemotherapeutic drug has yet been found. Therefore, the search for a highly effective, low-toxic, and safe natural anticancer therapy is a hot issue. MATERIAL AND METHODS SMMC-7721 cells (a hepatocellular carcinoma cell line) were treated with different concentrations of oleanolic acid (OA) plus autophagy inhibitor 3-methyladenine (3-MA) (3-MA+OA) or chloroquine (CQ) plus OA (CQ+OA). We used MTT and Hoechst 33258 staining methods to determine the proliferation and apoptotic effect of OA on cells. Flow cytometry was used to detect apoptosis. Mitochondrial function was assessed by measuring mitochondrial membrane potential and adenosine triphosphate (ATP) concentration. To evaluate the ability of OA on apoptosis and autophagy mechanisms on SMMC 7721 cells, the related protein expression for apoptosis, autophagy, and the autophagic pathway were detected and analyzed by western blot. RESULTS OA can inhibit and induce apoptosis of SMMC-7721 in a dose-dependent manner. Compared with the control group, OA significantly reduced the intracellular mitochondrial membrane potential, and the intracellular ATP concentration was also significantly reduced. Moreover, OA reduced the expression of p-Akt and p-mTOR. The expression of p62 was decreased, and LC3-II and Beclin-1 protein expression levels increased. After inhibiting autophagy with 3-MA or CQ, compared with OA alone, cell mitochondrial membrane potential and ATP concentration were significantly reduced, cell p62 expression was reduced, and LC3-II expression was increased, apoptosis-related protein Bax protein was increased, and Bcl-2 protein was decreased, which suggested that 3-MA or CQ treatment increased OA-induced apoptosis of SMMC-7721 cells. This suggested that OA activated autophagy of SMMC-7721 cells in a protective autophagic manner. CONCLUSIONS The study findings suggest that OA combined with autophagy inhibitor 3-MA can better exert its anticancer effect.

Liraglutide ameliorates COCl2-induced oxidative stress and apoptosis in H9C2 cells via regulating cell autophagy

Protective effects of liraglutide on H9C2 cells cultured using CoCl₂ and its mechanism of action were investigated. Hypoxia model was established using CoCl₂-treated H9C2 cells. With liraglutide as the treatment factor, apoptosis, changes in nitric oxide (NO) and reactive oxygen species (ROS) activity, mitochondrial membrane potential and change in cell autophagy level were detected via Hoechst staining, enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR) and western blotting (WB), respectively. Liraglutide ameliorated the CoCl₂-induced decrease in H9C2 cell viability, the increases in cytotoxicity and percentage of apoptotic cells as well as oxidative stress in cells. Moreover, it stimulated the elevation of cell autophagy level. However, the protective effects of liraglutide on H9C2 cells were attenuated remarkably after adding the cell autophagy inhibitor. Liraglutide can ameliorate the CoCl₂-induced oxidative stress and apoptosis in H9C2 cells via regulating cell autophagy.

miR-155 Regulates the Proliferation of Glioma Cells Through PI3K/AKT Signaling

Objective: Micro-RNA plays a critical role in the pathological process of gliomas. Previous research showed that the level of miR-155 was significantly increased in many cancers, including gliomas. However, the mechanism of glioma is still unknown. Method: To investigate the regulatory function of miR-155 on glioma U87-MG cells and its effects on related signaling pathways. After transfection of miR-155 mimic and inhibitor, the level of miR-155 were applied to detect cell proliferation, apoptosis, senescence index, invasive ability and cell migration at different time points (0, 24, 24 h, respectively) by CCK8 assay, flow cytometry, β-galactosidase (β-gal) staining, transwell and scratch test, respectively. The effect of miR-155 on PI3K/AKT signal pathway was observed at meantime. Results: Compared with the control group, after miR-155 mimic transfection, U87-MG cell viability, cell migration rate and invasiveness were increased, while apoptosis and senescence were significantly decreased, which was the opposite on miR-155 inhibitor transfection. The phosphorylation levels of miR-155, PI3K, AKT, PI3K, and AKT in U87-MG cells intervened with miR-155 mimic also increased significantly, while the levels of PTEN, Caspase-3, Caspase-9 mRNA, and protein declined significantly, with statistically significant difference. Meanwhile, compared with the control group, miR-155 inhibitor group were on the contrary. Conclusion: The study indicated that miR-155 take charge a key function in regulating the proliferation, migration, and invasion of glioma U87-MG cells through PI3K/AKT signaling pathway, and has anti-glioma effects by inhibition of miR-155, which provided ideas for further clinical treatment of glioma patients.

Apigenin Prevents Acetaminophen-Induced Liver Injury by Activating the SIRT1 Pathway

Acetaminophen (APAP) overdose is the main cause of acute liver failure. Apigenin (API) is a natural dietary flavonol with high antioxidant capacity. Herein, we investigated protection by API against APAP-induced liver injury in mice, and explored the potential mechanism. Cell viability assays and mice were used to evaluate the effects of API against APAP-induced liver injury. Western blotting, immunofluorescence staining, RT-PCR, and Transmission Electron Microscope were carried out to determine the signalling pathways affected by API. Analysis of mouse serum levels of alanine/aspartate aminotransferase (ALT/AST), malondialdehyde (MDA), liver myeloperoxidase (MPO) activity, glutathione (GSH), and reactive oxygen species (ROS) revealed that API (80 mg/kg) owned protective effect on APAP-induced liver injury. Meanwhile, API ameliorated the decreased cell viability in L-02 cells incubated by APAP with a dose dependent. Furthermore, API promoted SIRT1 expression and deacetylated p53. Western blotting showed that API promoted APAP-induced autophagy, activated the NRF2 pathway, and inhibited the transcriptional activation of nuclear p65 in the presence of APAP. Furthermore, SIRT1 inhibitor EX-527 reduced protection by API against APAP-induced hepatotoxicity. Molecular docking results indicate potential interaction between API and SIRT1. API prevents APAP-induced liver injury by regulating the SIRT1-p53 axis, thereby promoting APAP-induced autophagy and ameliorating APAP-induced inflammatory responses and oxidative stress injury.

Apigenin Inhibits Histamine-Induced Cervical Cancer Tumor Growth by Regulating Estrogen Receptor Expression

Apigenin is a natural flavone with anti-inflammatory and antioxidant properties and antitumor abilities against several types of cancers. Previous studies have found that the antitumor effects of apigenin may be due to its similar chemical structure to 17β-estradiol (E2), a main kind of estrogen in women. However, the precise mechanism underlying the antitumor effects of apigenin in cervical cancer remains unknown. On the other hand, there is increasing evidence that describes a histamine role in cancer cell proliferation. In this study, we examined whether apigenin can attenuate the effects of histamine on tumors by regulating the expression level of estrogen receptors (ERs) to inhibit cervical cancer growth. Our in vitro data indicates that apigenin inhibited cell proliferation in a dose-dependent manner in human cervical cancer cells (HeLa), while histamine shows the opposite effects. After that, the xenograft model was established to explore the antitumor effects of apigenin in vivo, the results show that apigenin inhibited cervical tumor growth by reversing the abnormal ER signal in tumor tissue which was caused by histamine. We also demonstrate that apigenin inhibited cell proliferation via suppressing the PI3K/Akt/mTOR signaling pathway. Collectively, our results suggest that apigenin may inhibit tumor growth through the ER-mediated PI3K/Akt/mTOR pathway and that it can also attenuate the effects of histamine on tumors.

Reactive oxygen species generation and mitochondrial dysfunction for the initiation of apoptotic cell death in human hepatocellular carcinoma HepG2 cells by a cyclic dipeptide Cyclo(-Pro-Tyr)

Cyclic dipeptides are increasingly gaining importance as considering its significant biological and pharmacological activities. This study was aimed to investigate the anticancer activity of a dipeptide Cyclo(-Pro-Tyr) (DP) identified from marine sponge Callyspongia fistularis symbiont Bacillus pumilus AMK1 and the underlying apoptotic mechanisms in the liver cancer HepG2 cell lines. MTT assay was done to demonstrate the cytotoxic effect of DP in HepG2 cells and mouse Fibroblast McCoy cells. Initially, apoptosis inducing activity of DP was identified using propidium iodide (PI) and acridine orange/ethidium bromide (AO/EB) dual staining, then it was confirmed by DNA fragmentation assay and western blotting analysis of apoptosis related markers Bax, Bcl-2, cytochrome c, caspase-3 and cleaved poly (ADP-ribose) polymerase (PARP). Rhodamine 123 staining was performed to observe DP effects on the mitochondrial membrane potential (MMP) and DCFH-DA (Dichloro-dihydro-fluorescein diacetate) staining was done to measure the intracellular reactive oxygen species (ROS) levels. The MTT results revealed that DP initiated dose-dependent cytotoxicity in HepG2 cells, but no significant toxicity in mouse Fibroblast McCoy cells treated with DP at the specified concentrations. DP induced apoptosis, which is confirmed by the appearance of apoptotic bodies with PI and AO/EB dual staining, and DNA fragmentation. DP significantly elevated the Bax/Bcl-2 ratio, disrupted the mitochondrial membrane potential (MMP), enhanced cytochrome c release from mitochondria, increased caspase-3 activation, the cleavage of PARP and increased intracellular reactive oxygen species (ROS) levels. Besides this, DP successfully inhibited the phosphorylation of PI3K, AKT and increased PTEN expression. These results suggested DP might have anti-cancer effect by initiating apoptosis through mitochondrial dysfunction and downregulating PI3K/Akt signaling pathway in HepG2 cells with no toxicity effect on normal fibroblast cells. Therefore, DP may be developed as a potential alternative therapeutic agent for treating hepatocellular carcinoma.

Neuroprotection by Walnut-Derived Peptides through Autophagy Promotion via Akt/mTOR Signaling Pathway against Oxidative Stress in PC12 Cells

Natural-derived peptides are effective substances in attenuating oxidative stress. However, their specific mechanisms have not been fully elucidated, especially in peptide-mediated autophagy. In the present study, TWLPLPR, YVLLPSPK, and KVPPLLY, novel peptides from Juglans mandshurica Maxim, prevented reactive oxygen species (ROS) production, elevated glutathione peroxidase (GSH-Px) activity and adenosine 5'-triphosphate (ATP) levels, and ameliorated apoptosis in Aβ_25-35 (at a concentration of 50 μM for 24 h)-induced PC12 cells (P < 0.01). Both western blot and immunofluorescence analysis illustrated that the peptides regulated Akt/mTOR signaling through p-Akt (Ser473) and p-mTOR (S2481) and promoted autophagy by increasing the levels of LC3-II/LC3-I and Beclin-1 while lowering p62 expression (P < 0.01). The autophagy inhibitor (3-methyladenine, 3-MA) and inducer (rapamycin, RAPA) were combined used to confirm the contribution of peptide-regulated autophagy in antioxidative effects. Moreover, the peptides increased the levels of LAMP1, LAMP2, and Cathepsin D (P < 0.05) and promoted the fusion with lysosomes to form autolysosomes, accelerating ROS removal. These data suggested that walnut-derived peptides regulated oxidative stress by promoting autophagy in the Aβ_25-35-induced PC12 cells.

Whole Transcriptomic Analysis of Apigenin on TNFα Immuno-activated MDA-MB-231 Breast Cancer Cells

BACKGROUND

Triple-negative breast cancer is categorized by a lack of hormone receptors, inefficacy of anti-estrogen or aromatase inhibitor chemotherapies and greater mortality rates in African American populations. Advanced-stage breast tumors have a high concentration of tumor necrosis factor-α (TNFα) throughout the tumor/stroma milieu, prompting sustained release of diverse chemokines (i.e. C-C motif chemokine ligand 2 (CCL2)/CCL5). These potent chemokines can subsequently direct mass infiltration of leukocyte sub-populations to lodge within the tumor, triggering a loss of tumor immune surveillance and subsequent rapid tumor growth. Previously, we demonstrated that in the MDA-MB-231 TNBC cell line, TNFα evoked a rise in immune signaling proteins: CCL2, granulocyte macrophage colony-stimulating factor, interleukin (IL)1α, IL6 and inhibitor of nuclear factor kappa-B kinase subunit epsilon (IKBKε) all of which were attenuated by apigenin, a dietary flavonoid found in chamomile and parsley.

MATERIALS AND METHODS

The present work elucidates changes evoked by TNFα in the presence or absence of apigenin by examining the entire transcriptome for mRNA and long intergenic non-coding RNA with Affymetrix Hugene-2.1_ST human microarrays. Differential gene-expression analysis was conducted on 48,226 genes.

RESULTS

TNFα caused up-regulation of 75 genes and down-regulation of 10. Of these, apigenin effectively down-regulated 35 of the 75 genes which were up-regulated by TNFα. These findings confirm our previous work, specifically for the TNFα-evoked spike in IL1A vs. untreated controls [+21-fold change (FC), p<0.0001] being attenuated by apigenin in the presence of TNFa (-15 FC vs. TNFα, p<0.0001). Similar trends were seen for apigenin-mediated down-regulation of TNFα-up-regulated transcripts: IKBKE (TNFα: 4.55 FC vs. control, p<0.001; and TNFα plus apigenin: -4.92 FC, p<0.001), CCL2 (2.19 FC, p<0.002; and -2.12 FC, p<0.003), IL6 (3.25 FC, p<0.020; and -2.85 FC, p<0.043) and CSF2 (TNFα +6.04 FC, p<0.001; and -2.36 FC, p<0.007). In addition, these data further establish more than a 65% reduction by apigenin for the following transcripts which were also up-regulated by TNFα: cathepsin S (CTSS), complement C3 (C3), laminin subunit gamma 2 (LAMC2), (TLR2), toll-like receptor 2 G protein-coupled receptor class C group 5 member B (GPRC5B), contactin-associated protein 1 (CNTNAP1), claudin 1 (CLDN1), nuclear factor of activated T-cells 2 (NFATC2), C-X-C motif chemokine ligand 10 (CXCL10), CXCL11, interleukin 1 receptor-associated kinase 3 (IRAK3), nuclear receptor subfamily 3 group C member 2 (NR3C2), interleukin 32 (IL32), IL24, slit guidance ligand 2 (SLIT2), transmembrane protein 132A (TMEM132A), TMEM171, signal transducing adaptor family member 2 (STAP2), mixed lineage kinase domain-like pseudokinase (MLKL), kinase insert domain receptor (KDR), BMP-binding endothelial regulator (BMPER), and kelch-like family member 36 (KLHL36).

CONCLUSION

There is a possible therapeutic role for apigenin in down-regulating diverse genes associated with tumorigenic leukocyte sub-population infiltration by triple-negative breast cancer. The data have been deposited into the Gene Expression Omnibus for public analysis at https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE120550.

Targeting PI3K/Akt/mTOR signaling pathway by polyphenols: Implication for cancer therapy

Cancer is one of the biggest challenges facing medicine and its cure is regarded to be the Holy Grail of medicine. Therapy in cancer is consisted as various artificial cytotoxic agents and radiotherapy, and recently immunotherapy. Recently much attention has been directed to the use of natural occurring agents in cancer therapy. One of the main group of agents utilized in this regard is polyphenols which are found abundantly in berries, fruits and vegetables. Polyphenols show to exert direct and indirect effects in progression of cancer, angiogenesis, proliferation and enhancing resistance to treatment. One of the cellular pathways commonly affected by polyphenols is PI3K/Akt/mTOR pathway, which has far ranging effects on multiple key aspects of cellular growth, metabolism and death. In this review article, evidence regarding the biology of polyphenols in cancer via PI3K/Akt/mTOR pathway is discussed and their application on cancer pathophysiology in various types of human malignancies is shown.

Autophagy: A Potential Therapeutic Target of Polyphenols in Hepatocellular Carcinoma

Autophagy is a conserved biological phenomenon that maintains cellular homeostasis through the clearing of damaged cellular components under cellular stress and offers the cell building blocks for cellular survival. Aberrations in autophagy subsidize to various human pathologies, such as dementia, cardiovascular diseases, leishmaniosis, influenza, hepatic diseases, and cancer, including hepatocellular carcinoma (HCC). HCC is the fifth common mortal type of liver cancer globally, with an inhomogeneous topographical distribution and highest incidence tripled in men than women. Existing treatment procedures with liver cancer patients result in variable success rates and poor prognosis due to their drug resistance and toxicity. One of the pathophysiological mechanisms that are targeted during the development of anti-liver cancer drugs is autophagy. Generally, overactivated autophagy may lead to a non-apoptotic form of programmed cell death (PCD) or autophagic cell death or type II PCD. Emerging evidence suggests that manipulation of autophagy could induce type II PCD in cancer cells, acting as a potential tumor suppressor. Hence, altering autophagic signaling offers new hope for the development of novel drugs for the therapy of resistant cancer cells. Natural polyphenolic compounds, including flavonoids and non-flavonoids, execute their anticarcinogenic mechanism through upregulating tumor suppressors and autophagy by modulating canonical (Beclin-1-dependent) and non-canonical (Beclin-1-independent) signaling pathways. Additionally, there is evidence signifying that plant polyphenols target angiogenesis and metastasis in HCC via interference with multiple intracellular signals and decrease the risk against HCC. The current review offers a comprehensive understanding of how natural polyphenolic compounds exhibit their anti-HCC effects through regulation of autophagy, the non-apoptotic mode of cell death.

Lupenone Protects Neuroblastoma SH-SY5y Cells Against Methamphetamine-Induced Apoptotic Cell Death via PI3K/Akt/mTOR Signaling Pathway

Methamphetamine (METH) is an addictive psychostimulant showing neurotoxicity through neuronal apoptosis and the neuro-inflammatory pathway. Lupenone, a lupane triterpenoid, is an isolated compound exhibiting anti-oxidative, anti-inflammation, and anti-diabetic activities. However, whether lupenone plays a protective role against apoptosis induced by METH in SH-SY5y neuroblastoma cells remains unknown. In the present study, we elucidated that lupenone had no toxicity to SH-SY5y cells at different concentrations. On the other hand, we found that the treatment of SH-SY5y cells with an optimal concentration of lupenone could lead to protection against cell death induced by METH. AnnexinV/PI apoptosis analysis revealed a dramatically reduced level of the apoptotic cell population in lupenon and METH treated SH-SY5y cells. Moreover, diminished expression of anti-apoptotic proteins, including Bcl-2, Caspase3, Caspase7, and Caspase8 in METH-exposed SH-SY5y cells, was significantly recovered by treatment with lupenone. This protection in the expression of anti-apoptotic proteins was due to an increased phosphorylation level of PI3K/Akt in METH-treated SH-SY5y cells pre-incubated with lupenone. These findings suggest that lupenone can protect SH-SY5y cells against METH-induced neuronal apoptosis through the PI3K/Akt pathway.

B7-H4 facilitates proliferation and metastasis of colorectal carcinoma cell through PI3K/Akt/mTOR signaling pathway

B7-H4 is over-expressed in various tumors and may affect many aspects of cancer biology. Our previous studies have reported that the over-expressed B7-H4 in serum or tumor tissue of colorectal carcinoma (CRC) patients was closely related to CRC progression. However, B7-H4 in cell biological characteristics of CRC is not well studied. Here, we investigate the effect of the B7-H4 on cell proliferation, migration and its expression regulated by PI3K/Akt/mTOR signaling pathway in CRC. Firstly, pSilencer 4.1-B7-H4-shRNA vector was constructed and stable transfection was performed on HT-29 cells. Secondly, cell proliferation, cell cycle, cell apoptosis and cell migration were evaluated after B7-H4 silencing, and the expression of Bcl-2, caspase-3, MMP-2 and MMP-9 was also measured. Finally, the regulation of B7-H4 by PI3K/Akt/mTOR signaling pathway was measured followed by treatment with or without PI3K/Akt and mTOR inhibitor. The results showed that the viability of HT-29 cells was significantly decreased after B7-H4 silencing (P < 0.05). B7-H4 silencing significantly increased the apoptosis rate and caspase-3 protein expression while decreased Bcl-2 protein expression (P all < 0.05). B7-H4 silencing also significantly reduced the migration of HT-29 cells (P < 0.01) and the secretion of MMP-2 or MMP-9 (P all < 0.05). Following treatment with PI3K/Akt and mTOR inhibitor in HT-29 cells, the expression of B7-H4 was significantly downregulated compared with untreated group (P all < 0.05). Our results strongly suggest that B7-H4 may be involved in cell proliferation and migration by PI3K/Akt/mTOR signaling pathway. Therefore, blocking B7-H4 signaling might be a novel treatment strategy for CRC.

Acetyl-11-Keto-β-Boswellic Acid Exerts the Anti-Cancer Effects via Cell Cycle Arrest, Apoptosis Induction and Autophagy Suppression in Non-Small Cell Lung Cancer Cells

Objective

Acetyl-11-keto-β-boswellic acid (AKBA) is a triterpenoid, which is the main component of boswellic acid from Boswellia Serrata, a medicinal plant that has shown immense potential in anti-cancer therapy. This study aims to explore the roles and molecular mechanisms of AKBA on cell behavior in non-small cell lung cancer (NSCLC) cells.

Materials and Methods

The effects of AKBA on the cell viability in A549, H460, H1299, and BEAS-2B cells were determined by the CCK-8 assay. The colony formation assay was used to identify the effects of AKBA on cell proliferation. Potential roles of AKBA in regulating the cell cycle, apoptosis, and autophagy in A549 were evaluated by flow cytometry, Western blotting, reverse transcription-polymerase chain reaction (PCR) and immunofluorescence (IF).

Results

AKBA reduced cell viability in A549, H460, H1299, and BEAS-2B. In A549 cells, AKBA suppressed the clone formation, arrested the cell cycle at the G₀/G₁ phase, induced cellular apoptosis. We found that AKBA suppressed the formation of autolysosome, and decreased the expression levels of Beclin-1, LC3A/B-I, and LC3A/B-II proteins. Furthermore, AKBA also inhibited the expression levels of PI3K/Akt signaling pathway proteins.

Conclusion

AKBA exerts the anti-cancer effects via cell cycle arrest, apoptosis induction, and autophagy suppression in NSCLC cells. This body of evidence supports the potential of AKBA as a promising drug in the treatment of NSCLC.

Health benefits of fucoxanthin in the prevention of chronic diseases

Fucoxanthin is a xanthophyll carotenoid abundant in macroalgae, such as brown seaweeds. When fucoxanthin is consumed, it can be esterified or hydrolyzed to fucoxanthinol in the gastrointestinal tract and further converted into amarouciaxanthin A in the liver. It has a unique chemical structure that confers its biological effects. Fucoxanthin has a strong antioxidant capacity by scavenging singlet molecular oxygen and free radicals. Also, it exerts an anti-inflammatory effect. Studies have demonstrated potential health benefits of fucoxanthin for the prevention of chronic diseases, such as cancer, obesity, diabetes mellitus, and liver disease. Animal studies have shown that fucoxanthin supplementation has no adverse effects. However, investigation of the safety of fucoxanthin consumption in humans is lacking. Clinical trials are required to assess the safety of fucoxanthin in conjunction with the study of mechanisms by which fucoxanthin exhibits its health benefits. This review focuses on current knowledge of metabolism and functions of fucoxanthin with its potential health benefits. This article is part of a Special Issue entitled Carotenoids recent advances in cell and molecular biology edited by Johannes von Lintig and Loredana Quadro.

Asparanin A from Asparagus officinalis L. Induces G0/G1 Cell Cycle Arrest and Apoptosis in Human Endometrial Carcinoma Ishikawa Cells via Mitochondrial and PI3K/AKT Signaling Pathways

Asparanin A (AA), a steroidal saponin from Asparagus officinalis L., has anticancer activity: however, its detailed molecular mechanisms in endometrial cancer (EC) have not been studied so far. We evaluated the anticancer activity and underlying mechanism of AA on EC cell line Ishikawa in vitro and in vivo. AA inhibited the Ishikawa cell proliferation and caused cell morphology alteration and cell cycle arrest in G0/G1 phase. Moreover, it could induce apoptosis through mitochondrial pathway, including the deregulation of Bak/Bcl-xl ratio which led to the generation of ROS, up-regulation of cytochrome c followed by decrease of Δψ_m, and activation of caspases, besides inhibition of the PI3K/AKT/mTOR pathway. In vivo data showed that administration of AA significantly inhibited the tumor tissue cell proliferation, reduced the tumor growth, and induced the apoptosis occurrence. AA can be a possible functional food ingredient to cure endometrial cancer followed by clinical trials.

Apigenin, A Plant Flavone Playing Noble Roles in Cancer Prevention Via Modulation of Key Cell Signaling Networks

Background:

Cancer is a global health problem and the continuous rise in incidence and mortality due to cancer carries a real economic burden to all countries. Accumulation of genetic mutation, exposure of environmental carcinogens and food habits due to change in lifestyles are the key reasons for cancer. Targeting cancer cells, we need a multitargeting molecule with low/no toxicity.

Objective :

To review the current update of the research status of chemopreventive/therapeutic molecule, Apigenin.

Methods:

Compare the results of the published articles and granted patents on this compound. We also discuss the pros and cons of the present research and future direction.

Results:

Cancer cells have characteristic alterations and dysregulation of various cell signaling pathways that control cell homeostasis, proliferation, motility, and survival in normal cells. Natural flavonoids are the compounds well known for their anti-inflammatory, anti-oxidant, and anti-cancerous properties. Apigenin, along with several other physiological effects, has a very low intrinsic toxicity and striking effects on the proliferation of cancer cells. Interestingly, this multitargeting molecule is getting wide acceptance among researchers. It is evident from the recent patents filed in this compound. At present, three patents have been granted only on the anticancer properties of apigenin.

Conclusion:

This mini-review will explain the present research status of apigenin and will further shine some light on how apigenin performs its anti-cancerous actions by interfering with the key cellsignaling pathways.

Apigenin induced autophagy and stimulated autophagic lipid degradation

Apigenin could induce autophagic lipid degradation by restoring the blocked autophagic flux in PA-induced HepG2 cells.

Natural products targeting the PI3K-Akt-mTOR signaling pathway in cancer: A novel therapeutic strategy

The phosphatidylinositol 3-kinase (PI3K)-Akt and the mammalian target of rapamycin (mTOR) represent two vital intracellular signaling pathways, which are associated with various aspects of cellular functions. These functions play vital roles in quiescence, survival, and growth in normal physiological circumstances as well as in various pathological disorders, including cancer. These two pathways are so intimately connected to each other that in some instances these are considered as one unique pathway crucial for cell cycle regulation. The purpose of this review is to emphasize the role of PI3K-Akt-mTOR signaling pathway in different cancer conditions and the importance of natural products targeting the PI3K-Akt-mTOR signaling pathway. This review also aims to draw the attention of scientists and researchers to the assorted beneficial effects of the numerous classes of natural products for the development of new and safe drugs for possible cancer therapy. We also summarize and critically analyze various preclinical and clinical studies on bioactive compounds and constituents, which are derived from natural products, to target the PI3K-Akt-mTOR signaling pathway for cancer prevention and intervention.

The Upstream Pathway of mTOR-Mediated Autophagy in Liver Diseases

Autophagy, originally found in liver experiments, is a cellular process that degrades damaged organelle or protein aggregation. This process frees cells from various stress states is a cell survival mechanism under stress stimulation. It is now known that dysregulation of autophagy can cause many liver diseases. Therefore, how to properly regulate autophagy is the key to the treatment of liver injury. mechanistic target of rapamycin (mTOR)is the core hub regulating autophagy, which is subject to different upstream signaling pathways to regulate autophagy. This review summarizes three upstream pathways of mTOR: the phosphoinositide 3-kinase (PI3K)/protein kinase (AKT) signaling pathway, the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway, and the rat sarcoma (Ras)/rapidly accelerated fibrosarcoma (Raf)/mitogen-extracellular activated protein kinase kinase (MEK)/ extracellular-signal-regulated kinase (ERK) signaling pathway, specifically explored their role in liver fibrosis, hepatitis B, non-alcoholic fatty liver, liver cancer, hepatic ischemia reperfusion and other liver diseases through the regulation of mTOR-mediated autophagy. Moreover, we also analyzed the crosstalk between these three pathways, aiming to find new targets for the treatment of human liver disease based on autophagy.

MiR-146b inhibits autophagy in prostate cancer by targeting the PTEN/Akt/mTOR signaling pathway

Prostate cancer (PCa) is considered as a common visceral cancer in males and the sixth major cause of cancer-related deaths in males worldwide. Significant diagnostic and therapeutic advances have been made in the past decades. However, an improved understanding of their molecular mechanism is still needed. In the present research, we first detected the expression of miR-146b by quantitative real-time PCR (qRT-PCR) and found that miR-146b expression was increased in PCa. Subsequently, we found that miR-146b play an important role in the viability and proliferation capacity of PCa cells functionally. To explore the mechanism, we performed western blot to examine the autophagy-related markers, and found that miR‑146b may promote autophagy in PCa cells via activation of PTEN/AKT/mTOR signaling pathway. Furthermore, we performed the dual luciferase reporter assay to clarify the relationship between miR-146b and PTEN. In conclusion, this study demonstrated that miR-146b inhibited autophagy in PCa by targeting the PTEN/Akt/mTOR signaling pathway, and it could be a potential candidate for application in the treatment of PCa.

Complement factor H‑related 3 overexpression affects hepatocellular carcinoma proliferation and apoptosis

Complement factor H‑related 3 (CFHR3) belongs to the human factor H protein family and is associated with various human diseases, including nephropathy, age‑related macular degeneration and atypical hemolytic uremic syndrome. However, to the best of our knowledge, the role of CFHR3 in hepatocellular carcinoma (HCC) remains largely unknown. In the present study, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blot analysis were performed to determine mRNA and protein expression levels of CFHR3 in HCC and normal adjacent tissue. In addition, CFHR3 was overexpressed in Huh‑7 cells and cell counting kit‑8 assay was used to determine cell viability. Cell proliferation and apoptosis were assessed using flow cytometry, RT‑qPCR and western blotting. The results demonstrated that mRNA (2‑ΔΔCq) and protein expression levels of CFHR3 were significantly lower in tumor tissue compared with in adjacent tissue. Additionally, CFHR3 overexpression decreased cell viability, inhibited cell proliferation and significantly increased apoptosis. It was also identified that CFHR3 could downregulate the expression of Ki67. The results suggested that CFHR3 induced apoptosis by downregulating the expression of survivin and B cell lymphoma 2, upregulating the expression of Bcl‑2‑associated X and promoting caspase‑3 activity. Western blotting revealed that CFHR3 significantly inhibited the protein expression levels of phosphorylated (p)‑phosphoinositide 3‑kinase (PI3K), p‑protein kinase B (Akt) and p‑mammalian target of rapamycin (mTOR). Overexpression of CFHR3 suppressed proliferation and promoted apoptosis of HCC cells by inhibiting the PI3K/Akt/mTOR signaling pathway.

Paeonol induces cytoprotective autophagy via blocking the Akt/mTOR pathway in ovarian cancer cells

Paeonol (Pae), a phenolic acid compound isolated from the Moutan Cortex, was previously demonstrated to exert multiple anticancer effects. The rational control of autophagy has been considered a potential treatment strategy for epithelial ovarian cancer. However, whether Pae induces autophagy and the relationship between its antitumour activities and autophagy in epithelial ovarian cancer are still unclear. In this study, we found that Pae induced not only antiproliferation activity and apoptosis but also autophagy, and complete autophagic flux was observed in A2780 and SKOV3 cells. In addition, combination treatment with Pae and an autophagy inhibitor (3-methyladenine and hydroxychloroquine) showed significant synergetic effects on inhibiting cell viability and promoting apoptosis in vitro and in the A2780 xenograft model, without severe side effects, which was often had by cisplatin. These results indicate that autophagy induced by Pae has a cytoprotective role in both A2780 and SKOV3 cells. Mechanistically, we found that Pae inhibited the protein kinase B(Akt)/mammalian target of rapamycin (mTOR) pathway. Furthermore, when combined with the inhibitors MK2206 and rapamycin to inhibit Akt and mTOR kinase activity, Pae-induced autophagy was increased. Taken together, our results demonstrate that Pae induced cytoprotective autophagy by inhibiting the Akt/mTOR pathway in ovarian cancer cells. Thus, the strategy of combining Pae with an autophagy inhibitor to block Akt/mTOR-dependent autophagy could enhance the antitumour activity of Pae and warrants further application for the treatment of ovarian cancer.

The antidepressant effects of apigenin are associated with the promotion of autophagy via the mTOR/AMPK/ULK1 pathway

The present study aimed to investigate whether apigenin elicits antidepressant effects in depressant‑like mice via the regulation of autophagy. The depressant‑like behaviors were established in a chronic restraint stress model. Male BALB/c mice were subjected to restraint stress for 6 h/day for a period of 21 days, and deficits in sucrose preference, tail suspension and forced swim tests were confirmed to be improved following oral apigenin. To investigate the underlining mechanisms, the hippocampal levels of p62 and microtubule‑associated protein light chain 3‑II/I (LC3‑II/I) were measured using western blot analysis. The expression levels of LC3‑II/I and p62 indicated that the significantly inhibited autophagy level induced by chronic restraint stress can be increased following apigenin treatment. Similar to the level of autophagy, the expression levels of adenosine monophosphate‑activated protein kinase (AMPK) and Unc‑51 like autophagy activating kinase‑1 were downregulated after chronic restraint stress stimulation and, subsequently upregulated following treatment with apigenin. Conversely, the levels of mammalian target of rapamycin (mTOR) were increased in chronic restraint stress mice and inhibited by apigenin. Collectively, the present findings indicated that apigenin potentially promotes autophagy via the AMPK/mTOR pathway and induces antidepressive effects in chronic restraint stress mice.

NPS2390, a Selective Calcium-sensing Receptor Antagonist Controls the Phenotypic Modulation of Hypoxic Human Pulmonary Arterial Smooth Muscle Cells by Regulating Autophagy

Background and Objectives

Calcium-sensing receptor (CaSR) is known to regulate hypoxia-induced pulmonary hypertension (HPH) and vascular remodeling via the phenotypic modulation of pulmonary arterial smooth muscle cells (PASMCs) in small pulmonary arteries. Moreover, autophagy is an essential modulator of VSMC phenotype. But it is not clear whether CaSR can regulate autophagy involving the phenotypic modulation under hypoxia.

Methods

The viability of human PASMCs was detected by cell cycle and BrdU. The expressions of proliferation protein, phenotypic marker protein, and autophagy protein in human PASMCs were determined by western blot.

Results

Our results showed that hypoxia-induced autophagy was considerable at 24 h. The addition of NPS2390 decreased the expression of autophagy protein and synthetic phenotype marker protein osteopontin and increased the expression of contractile phenotype marker protein SMA-ɑ and calponin via suppressing downstream PI3K/Akt/mTOR signal pathways.

Conclusions

Our study demonstrates that treatment of NPS2390 was conducive to inhibit the proliferation and reverse phenotypic modulation of PASMCs by regulating autophagy levels.

Alisol B 23‑acetate inhibits the viability and induces apoptosis of non‑small cell lung cancer cells via PI3K/AKT/mTOR signal pathway

The aim of the present study was to investigate the effects of alisol B 23‑acetate (AB23A) on inhibiting the viability and inducing apoptosis of human non‑small cell lung cancer (NSCLC) cells and the anticancer mechanisms of AB23A in vitro. The viability of A549 cells following treatment with different doses of AB23A was examined using a Cell Counting Kit‑8 assay. Subsequently, apoptosis and the cell cycle were detected using flow cytometric analysis. The effect of AB23A on migration and invasion of A549 cells was detected by wound healing and Transwell assays. Western blotting was performed to determine the relative expression of Bax/Bcl‑2, phosphatidylinositol 3‑kinase (PI3K), protein kinase B (AKT) and mammalian target of rapamycin (mTOR). AB23A markedly inhibited the viability enhanced apoptosis of A549 cells and arrested the cell cycle in G1 phase. Additionally, AB23A upregulated the ratio of Bax/Bcl‑2 in the A549 cells in a concentration‑dependent manner. The results of wound healing and Transwell assays indicated that AB23A also suppresses the migration and invasion ability of A549 cells. Furthermore, AB23A reduced the protein levels of phosphorylated AKT, PI3K and mTOR. In conclusion, AB23A exerted anti‑cancer activity via inhibiting cells viability, migration and invasion, and promoting apoptosis. Therefore, AB23A is a potential antitumor drug for the treatment of NSCLC.

IGFBPrP1 accelerates autophagy and activation of hepatic stellate cells via mutual regulation between H19 and PI3K/AKT/mTOR pathway

BACKGROUND

Our previous study found that insulin-like growth factor binding protein-associated protein (IGFBPrP1) drives hepatic stellate cells (HSCs) activation, and IGFBPrP1 and transforming growth factor β1 (TGFβ1) likely interact with each other to promote HSCs activation. TGFβ1 reportedly promotes autophagy and contributes to HSCs activation; however, the mechanism between IGFBPrP1 and autophagy in liver fibrogenesis is yet unknown. Moreover, long noncoding RNA (lncRNA) H19 participates in autophagy regulation and plays a crucial function in liver fibrosis.

AIMS

To define the relationship between IGFBPrP1 and autophagy and the role of H19 in IGFBPrP1-induced hepatic fibrosis.

METHODS

IGFBPrP1 and autophagy were detected in bile duct ligation (BDL)-induced hepatic fibrosis. Adenovirus-mediated IGFBPrP1 was transfected into mouse liver and JS-1 cells with or without LY294002 or rapamycin to examine the effects of IGFBPrP1 on HSCs activation and autophagy as well as the PI3K/AKT/mTOR pathway. lncRNA H19 in liver fibrosis tissues and JS-1 cells induced by IGFBPrP1 were detected, then autophagy and HSCs activation level were detected in JS-1 cells by IGFBPrP1 with H19 overexpression or knowdown.

RESULTS

IGFBPrP1 expression and autophagy level were concomitantly increased in liver tissue with BDL-induced hepatic fibrosis. Furthermore, we found that IGFBPrP1 stimulated autophagy and HSCs activation in vivo and in vitro, and PI3K/AKT/mTOR signaling pathway was involved in the regulation of autophagy by IGFBPrP1. In addition, H19 promoted autophagy by interacting with the PI3K/AKT/mTOR pathway in IGFBPrP1-induced HSCs activation.

CONCLUSIONS

IGFBPrP1 promoted autophagy and contributed to HSCs activation via mutual regulation between H19 and the PI3K/AKT/mTOR pathway.

NF-κB signaling and crosstalk during carcinogenesis

Transcription factors (TFs) are proteins that control the transcription of genetic information from DNA to mRNA by binding to specific DNA sequences either on their own or with other proteins as a complex. TFs thus support or suppress the recruitment of the corresponding RNA polymerase. In general, TFs are classified by structure or function. The TF, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), is expressed in all cell types and tissues. NF-κB signaling and crosstalk are involved in several steps of carcinogenesis including in sequences involving pathogenic stimulus, chronic inflammation, fibrosis, establishment of its remodeling to the precancerous niche (PCN) and transition of a normal cell to a cancer cell. Triggered by various inflammatory cytokines, NF-κB is activated along with other TFs with subsequent stimulation of cell proliferation and inhibition of apoptosis. The involvement of NF-κB in carcinogenesis provides an opportunity to develop anti-NF-κB therapies. The complexity of these interactions requires that we elucidate those aspects of NF-κB interactions that play a role in carcinogenesis, the sequence of events leading to cancer.

Long noncoding RNA HAGLROS promotes cell proliferation, inhibits apoptosis and enhances autophagy via regulating miR-5095/ATG12 axis in hepatocellular carcinoma cells

In this research, we planned to dig the possible influences and mechanism of long noncoding (lnc) RNA HAGLROS in the development and progression of hepatocellular carcinoma (HCC). The levels of lncRNA HAGLROS in HCC tumor samples and their relationship with clinicopathological characteristics and prognosis of patients with HCC were studied. Subsequently, overexpression and silenced approaches were used in HCC cells for detecting the effects of lncRNA HAGLROS on cell viability, apoptosis, and autophagy. Furthermore, we investigated whether HAGLROS could function as a competing endogenous RNA (ceRNA) to regulate miR-5095 expression in HCC cells, and explored the correlation between miR-5095 and ATG12. Besides, the correlation of HAGLROS, the consequent PI3K/AKT/mTOR signaling pathway was further explored. The level of HAGLROS was higher in HCC tissues and correlated with clinical performances including tumor stages or tumor differentiation. In contrast to the lower level, a higher level of HAGLROS correlated with a shorter survival time of patients with HCC. The suppression of HAGLROS decreased cell viability, promoted apoptosis, and inhibited autophagy. Moreover, HAGLROS negatively regulated miR-5095 expression, which further regulated HCC cell viability, apoptosis, and autophagy. In addition, ATG12 was targeted by miR-5095 and was then involved in miR-5095-regulated HCC cell biological processes including viability, apoptosis, and autophagy. Furthermore, overexpression of HAGLROS activated PI3K/AKT/mTOR signals. Our results revealed that HAGLROS is highly expressed in HCC, and its high level may correlate with the progression and development of HCC involving the processes of cell viability, apoptosis, and autophagy through the miR-5095/ATG12 axis and PI3K/AKT/mTOR signals.

Flavonoids: Broad Spectrum Agents on Chronic Inflammation

Flavonoids are major plant constituents with numerous biological/pharmacological actions both in vitro and in vivo. Of these actions, their anti-inflammatory action is prominent. They can regulate transcription of many proinflammatory genes such as cyclooxygenase-2/inducible nitric oxide synthase and many cytokines/chemokines. Recent studies have demonstrated that certain flavonoid derivatives can affect pathways of inflammasome activation and autophagy. Certain flavonoids can also accelerate the resolution phase of inflammation, leading to avoiding chronic inflammatory stimuli. All these pharmacological actions with newly emerging activities render flavonoids to be potential therapeutics for chronic inflammatory disorders including arthritic inflammation, meta-inflammation, and inflammaging. Recent findings of flavonoids are summarized and future perspectives are presented in this review.

Discovery of an EGFR tyrosine kinase inhibitor from Ilex latifolia in breast cancer therapy

Deficient signaling of the EGFR and other receptor tyrosine kinases in humans is associated with diseases such as cancer. Some EGFR tyrosine kinase inhibitors have become a new class of targeted therapeutic agents in the last years. We found that 27-O-p-(E)-coumaroyl ursolic acid (27-CAUA) had a strong activity of apoptosis according to preparation by screening for a series of Ilex latifolia products. 27-CAUA inhibited EGFR kinase system to lead to inactivation of PI3K/AKT/mTOR and Ras-Raf-MEK-ERK signal pathways which implicated in the proliferation and survival of tumor cells. These findings suggested that 27-CAUA was an orally active, selective epidermal growth factor receptor-tyrosine kinase inhibitor which could lead to beneficial manifestations in the clinic.

Stem-leaf saponins from Panax notoginseng counteract aberrant autophagy and apoptosis in hippocampal neurons of mice with cognitive impairment induced by sleep deprivation

Backgroud

Sleep deprivation (SD) impairs learning and memory by inhibiting hippocampal functioning at molecular and cellular levels. Abnormal autophagy and apoptosis are closely associated with neurodegeneration in the central nervous system. This study is aimed to explore the alleviative effect and the underlying molecular mechanism of stem–leaf saponins of Panax notoginseng (SLSP) on the abnormal neuronal autophagy and apoptosis in hippocampus of mice with impaired learning and memory induced by SD.

Methods

Mouse spatial learning and memory were assessed by Morris water maze test. Neuronal morphological changes were observed by Nissl staining. Autophagosome formation was examined by transmission electron microscopy, immunofluorescent staining, acridine orange staining, and transient transfection of the tf-LC3 plasmid. Apoptotic event was analyzed by flow cytometry after PI/annexin V staining. The expression or activation of autophagy and apoptosis-related proteins were detected by Western blotting assay.

Results

SLSP was shown to improve the spatial learning and memory of mice after SD for 48 h, accomanied with restrained excessive autophage and apoptosis, whereas enhanced activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway in hippocampal neurons. Meanwhile, it improved the aberrant autophagy and apoptosis induced by rapamycin and re-activated phosphoinositide 3-kinase/Akt/mammalian target of rapamycin signaling transduction in HT-22 cells, a hippocampal neuronal cell line.

Conclusion

SLSP could alleviate cognitive impairment induced by SD, which was achieved probably through suppressing the abnormal autophagy and apoptosis of hippocampal neurons. The findings may contribute to the clinical application of SLSP in the prevention or therapy of neurological disorders associated with SD.

Deciphering the Molecular Mechanisms Sustaining the Estrogenic Activity of the Two Major Dietary Compounds Zearalenone and Apigenin in ER-Positive Breast Cancer Cell Lines

The flavone apigenin and the mycotoxin zearalenone are two major compounds found in the human diet which bind estrogen receptors (ERs), and therefore influence ER activity. However, the underlying mechanisms are not well known. To unravel the molecular mechanisms that could explain the differential effect of zearalenone and apigenin on ER-positive breast cancer cell proliferation, gene-reporter assays, chromatin immunoprecipitation (ChIP) experiments, proliferation assays and transcriptomic analysis were performed. We found that zearalenone and apigenin transactivated ERs and promoted the expression of estradiol (E2)-responsive genes. However, zearalenone clearly enhanced cellular proliferation, while apigenin appeared to be antiestrogenic in the presence of E2 in both ER-positive breast cancer cell lines, MCF-7 and T47D. The transcriptomic analysis showed that both compounds regulate gene expression in the same way, but with differences in intensity. Two major sets of genes were identified; one set was linked to the cell cycle and the other set was linked to stress response and growth arrest. Our results show that the transcription dynamics in gene regulation induced by apigenin were somehow different with zearalenone and E2 and may explain the differential effect of these compounds on the phenotype of the breast cancer cell. Together, our results confirmed the potential health benefit effect of apigenin, while zearalenone appeared to be a true endocrine-disrupting compound.

Anticancer effects and underlying mechanism of Colchicine on human gastric cancer cell lines in vitro and in vivo

The present study investigated the effects of Colchicine on gastric carcinoma (GC) cells and explored its possible mechanisms underlying such effects. The results of MTT and colony formation assays showed that Colchicine (2, 5, and 10 ng/ml) markedly inhibited the proliferation of AGS and NCI-N87 cells in a dose-dependent manner. It also led to a reduction in cell migration in both GC cells as determined by Transwell migration assay. Mover, data form Hoechst 33342 staining and flow cytometry assay indicated that Colchicine (2, 5, and 10 ng/ml) promoted the apoptosis of NCI-N87 cells. In addition, the release of cytochrome c, the activation of bax, and the inhibition of bcl-2 were observed in NCI-N87 cells treated with Colchicine. Furthermore, the in vivo experiment further confirmed that Colchicine administration remarkably suppressed the tumor growth in nude mice via induction of apoptosis at 0.05 and 0.1 mg/kg. In addition, no visible toxicity was observed in liver and renal tissue of mice. This finding suggests that Colchicine-induced apoptosis is associated with caspase-3-mediated mitochondrial apoptotic pathways.

In situ biosynthesized gold nanoclusters inhibiting cancer development via the PI3K–AKT signaling pathway

Nanomaterials have made great breakthroughs in drug delivery.

Relevance of Autophagy in Parenchymal and Non-Parenchymal Liver Cells for Health and Disease

Autophagy is a highly conserved intracellular process for the ordered degradation and recycling of cellular components in lysosomes. In the liver, parenchymal cells (i.e., mainly hepatocytes) utilize autophagy to provide amino acids, glucose, and free fatty acids as sources of energy and biosynthesis functions, but also for recycling and controlling organelles such as mitochondria. Non-parenchymal cells of the liver, including endothelial cells, macrophages (Kupffer cells), and hepatic stellate cells (HSC), also employ autophagy, either for maintaining cellular homeostasis (macrophages, endothelium) or for providing energy for their activation (stellate cells). In hepatocytes, autophagy contributes to essential homeostatic functions (e.g., gluconeogenesis, glycogenolysis, fatty acid oxidation), but is also implicated in diseases. For instance, storage disorders (alpha 1 antitrypsin deficiency, Wilson's disease), metabolic (non-alcoholic steatohepatitis, NASH), and toxic (alcohol) liver diseases may benefit from augmenting autophagy in hepatocytes. In hepatic fibrosis, autophagy has been implicated in the fibrogenic activation of HSC to collagen-producing myofibroblasts. In hepatocellular carcinoma (HCC), autophagy may contribute to tumor surveillance as well as invasiveness, indicating a dual and stage-dependent function in cancer. As many drugs directly or indirectly modulate autophagy, it is intriguing to investigate autophagy-targeting, possibly even cell type-directed strategies for the treatment of hereditary liver diseases, NASH, fibrosis, and HCC.

Targeting Cancer with Phytochemicals via Their Fine Tuning of the Cell Survival Signaling Pathways

The role of phytochemicals as potential prodrugs or therapeutic substances against tumors has come in the spotlight in the very recent years, thanks to the huge mass of encouraging and promising results of the in vitro activity of many phenolic compounds from plant raw extracts against many cancer cell lines. Little but important evidence can be retrieved from the clinical and nutritional scientific literature, where flavonoids are investigated as major pro-apoptotic and anti-metastatic compounds. However, the actual role of these compounds in cancer is still far to be fully elucidated. Many of these phytochemicals act in a pleiotropic and poorly specific manner, but, more importantly, they are able to tune the reactive oxygen species (ROS) signaling to activate a survival or a pro-autophagic and pro-apoptosis mechanism, depending on the oxidative stress-responsive endowment of the targeted cell. This review will try to focus on this issue.

Alpha-fetoprotein inhibits autophagy to promote malignant behaviour in hepatocellular carcinoma cells by activating PI3K/AKT/mTOR signalling

Alpha-fetoprotein (AFP) has been recognized as a key regulator of cell proliferation in hepatocellular carcinoma (HCC). However, whether AFP functions in cancer cell autophagy remains unknown. This study investigated the effects of AFP on autophagy in HCC cells. The role of AFP was studied in two HCC cell lines, PLC/PRF/5 and HLE. Cell autophagy, apoptosis, proliferation, migration and invasion were analysed with Western blotting, co-immunoprecipitation (CoIP), immunofluorescence, animal models, MTT assays, flow cytometry (FCM), Cell Counting Kit (CCK)-8, and scratch and transwell assays. In PLC/PRF/5 cells, AFP interacted with PTEN and activated PI3K/Akt/mTOR signalling. In HLE cells, overexpressed AFP similarly interacted with PTEN, leading to PI3K/Akt/mTOR activation and reduced cell autophagy. When AFP was silenced in PLC/PRF/5 cells, cell proliferation, tumour growth, migration and invasion were inhibited, and the numbers of S-phase and apoptotic cells were increased. In contrast, AFP overexpression in HLE cells enhanced cell proliferation, migration and invasion and reduced apoptosis. AFP-dependent autophagy, proliferation, migration and apoptosis were inhibited by rapamycin. In summary, AFP plays critical roles in the inhibition of autophagy and apoptosis in HCC cells and promotes proliferation, migration and invasion. The role of AFP in autophagy inhibition in HCC cells may involve the activation of PI3K/Akt/mTOR signalling.

Effects of Acute Cold Stress on Liver O-GlcNAcylation and Glycometabolism in Mice

Protein O-linked β-N-acetylglucosamine glycosylation (O-GlcNAcylation) regulates many biological processes. Studies have shown that O-GlcNAc modification levels can increase during acute stress and suggested that this may contribute to the survival of the cell. This study investigated the possible effects of O-GlcNAcylation that regulate glucose metabolism, apoptosis, and autophagy in the liver after acute cold stress. Male C57BL/6 mice were exposed to cold conditions (4 °C) for 0, 2, 4, and 6 h, then their livers were extracted and the expression of proteins involved in glucose metabolism, apoptosis, and autophagy was determined. It was found that acute cold stress increased global O-GlcNAcylation and protein kinase B (AKT) phosphorylation levels. This was accompanied by significantly increased activation levels of the glucose metabolism regulators 160 kDa AKT substrate (AS160), 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2 (PFKFB2), and glycogen synthase kinase-3β (GSK3β). The levels of glycolytic intermediates, fructose-1,6-diphosphate (FDP) and pyruvic acid (PA), were found to show a brief increase followed by a sharp decrease. Additionally, adenosine triphosphate (ATP), as the main cellular energy source, had a sharp increase. Furthermore, the B-cell lymphoma 2(Bcl-2)/Bcl-2-associated X (Bax) ratio was found to increase, whereas cysteine-aspartic acid protease 3 (caspase-3) and light chain 3-II (LC3-II) levels were reduced after acute cold stress. Therefore, acute cold stress was found to increase O-GlcNAc modification levels, which may have resulted in the decrease of the essential processes of apoptosis and autophagy, promoting cell survival, while altering glycose transport, glycogen synthesis, and glycolysis in the liver.