Role of p38 and JNK MAPK signaling pathways and tumor suppressor p53 on induction of apoptosis in response to Ad-eIF5A1 in A549 lung cancer cells

ARF6 promotes Streptococcus suis suilysin induced apoptosis in HBMECs

Streptococcus suis (S. suis) is a significant zoonotic microorganism that causes a severe illness in both pigs and humans and is characterized by severe meningitis and septicemia. Suilysin (SLY), which is secreted by S. suis, plays a crucial role as a virulence factor in the disease. To date, the interaction between SLY and host cells is not fully understood. In this study, we identified the interacting proteins between SLY and human brain microvascular endothelial cells (HBMECs) using the TurboID-mediated proximity labeling method. 251 unique proteins were identified in TurboID-SLY treated group, of which six plasma membrane proteins including ARF6, GRK6, EPB41L5, DSC1, TJP2, and PNN were identified. We found that the proteins capable of interacting with SLY are ARF6 and PNN. Subsequent investigations revealed that ARF6 substantially increased the invasive ability of S. suis in HBMECs. Furthermore, ARF6 promoted SLY-induced the activation of p38 MAPK signaling pathway in HBMECs. Moreover, ARF6 promoted the apoptosis in HBMECs through the activation of p38 MAPK signaling pathway induced by SLY. Finally, we confirmed that ARF6 could increase the virulence of SLY in C57BL/6 mice. These findings offer valuable insights that contribute to a deeper understanding of the pathogenic mechanism of SLY.

Exosomes in the pathogenesis and treatment of cancer-related cachexia

Cancer-related cachexia is a metabolic syndrome characterized by weight loss, adipose tissue decomposition, and progressive skeletal muscle atrophy. It is a major complication of many advanced cancers and seriously affects the quality of life and survival of cancer patients. However, the specific molecules that mediate cancer-related cachexia remain elusive, and the fundamental cellular and molecular mechanisms associated with muscle atrophy and lipidolysis in cancer patients still need to be investigated. Exosomes, a newly discovered class of small extracellular vesicles that facilitate intercellular communication, have a significant role in the onset and development of various cancers. Studies have shown that exosomes play a role in the onset and progression of cancer-related cachexia by transporting active molecules such as nucleic acids and proteins. This review aimed to provide an overview of exosome developments in cancer-induced skeletal muscle atrophy and adipose tissue degradation. More importantly, exosomes were shown to have potential as diagnostic markers or therapeutic strategies for cachexia and were prospected, providing novel strategies for the diagnosis and treatment of cancer-related cachexia.

Fractionation and phytochemical composition of an ethanolic extract of Ziziphus nummularia leaves: antioxidant and anticancerous properties in human triple negative breast cancer cells

Natural products have long been utilized in traditional medicine as remedies to improve health and treat illnesses, and have had a key role in modern drug discovery. Recently, there has been a revived interest in the search for bioactives from natural sources as alternative or complementary modalities to synthetic medicines; especially for cancer treatment, which incidence and mortality rates are on the rise worldwide. Ziziphus nummularia has been widely used in traditional medicine for the treatment of various diseases. Its traditional uses and numerous ethnopharmacological properties may be attributed to its richness in bioactive metabolites. However, its phytochemical composition or chemopreventive effects against the aggressive triple-negative breast cancer (TNBC) are still poorly explored. Here, phytochemical composition of an ethanolic extract of Z. nummularia leaves (ZNE) and its chromatographically isolated fractions was identified both qualitatively by spectrophotometric assays and analytically by HPLC-PDA-MS/MS. The anti-proliferative effects of ZNE were tested in several cancer cell lines, but we focused on its anti-TNBC effects since they were not explored yet. The anti-cancerous potential of ZNE and its fractions was tested in vitro in MDA-MB-231, a TNBC cell line. Results showed that ZNE and its Fraction 6 (F6) reduced the viability of MDA-MB-231 cells. F6 decreased MDA-MB-231 viability more than crude ZNE or its other fractions. ZNE and F6 are rich in phytochemicals and HPLC-PDA-MS/MS analysis identified several metabolites that were previously reported to have anti-cancerous effects. Both ZNE and F6 showed potent antioxidant capacity in the DPPH assay, but promoted reactive oxygen species (ROS) production in MDA-MB-231 cells; an effect which was blunted by the antioxidant N-acetyl cysteine (NAC). NAC also blunted ZNE- and F6-induced reduction in TNBC cell viability. We also demonstrated that ZNE and F6 induced an arrest of the cell cycle, and triggered apoptosis- and autophagy-mediated cell death. ZNE and F6 inhibited metastasis-related cellular processes by modifying cell migration, invasion, and adhesion. Taken together, our findings reveal that Z. nummularia is rich in phytochemicals that can attenuate the malignant phenotype of TNBC and may offer innovative avenues for the discovery of new drug leads for treatment of TNBC and other cancers.

Antheraea proylei J. Sericin Induces Apoptosis in a Caspase-dependent Manner in A549 and HeLa Cells

BACKGROUND

In spite of much progress in cancer, the global cancer burden is still significant and increasing. Sericin, an adhesive protein of silk cocoons, has been shown to be a potential protein in various biomedical applications, including cancer therapeutics. The present study evaluates the anticancer property of sericin from cocoons of Antheraea proylei J (SAP) against human lung cancer (A549) and cervical cancer (HeLa) cell lines. This is the first report of anti-cancer activity of the non-mulberry silkworm A. proylei J.

OBJECTIVE

Establish the antiproliferative potential of SAP. 2. Identify the molecular mechanism of cell death induced by SAP on two different cell lines.

AIMS

To investigate the anticancer activity of sericin preparation from cocoons of A. proylei.

METHODS

SAP was prepared from cocoons of A. proylei J. by the process of the degumming method. Cytotoxic activity was assessed by MTT assay, and genotoxicity was assessed by comet assay. Cleavage of caspase and PARP proteins and phosphorylation of MAPK pathway members were analysed by Western blotting. Cell cycle analysis was done by flow cytometer.

RESULTS

SAP causes cytotoxicity to A549 and HeLa cell lines with the IC50 values 3.8 and 3.9 μg/μl respectively. SAP induces apoptosis in a dose-dependent manner through caspase-3 and p38, MAPK pathways in A549 and HeLa cells. Moreover, in A549 and HeLa cells, SAP induces cell cycle arrest at the S phase in a dose-dependent manner.

CONCLUSION

The difference in the molecular mechanisms of apoptosis induced by SAP in A549 and HeLa cell lines may be due to the difference in the genotypes of the cancer cell lines. However, further investigation is warranted. The overall results of the present study envisage the possibility of using SAP as an anti-tumorigenic agent.

Effects of small molecules on neurogenesis: Neuronal proliferation and differentiation

Neurons are believed to be non-proliferating cells. However, neuronal stem cells are still present in certain areas of the adult brain, although their proliferation diminishes with age. Just as with other cells, their proliferation and differentiation are modulated by various mechanisms. These mechanisms are foundational to the strategies developed to induce neuronal proliferation and differentiation, with potential therapeutic applications for neurodegenerative diseases. The most common among these diseases are Parkinson's disease and Alzheimer's disease, associated with the formation of β -amyloid (Aβ ) aggregates which cause a reduction in the number of neurons. Compounds such as LiCl, 4-aminothiazoles, Pregnenolone, ACEA, harmine, D2AAK1, methyl 3,4-dihydroxybenzoate, and shikonin may induce neuronal proliferation/differentiation through the activation of pathways: MAPK ERK, PI3K/AKT, NFκ B, Wnt, BDNF, and NPAS3. Moreover, combinations of these compounds can potentially transform somatic cells into neurons. This transformation process involves the activation of neuron-specific transcription factors such as NEUROD1, NGN2, ASCL1, and SOX2, which subsequently leads to the transcription of downstream genes, culminating in the transformation of somatic cells into neurons. Neurodegenerative diseases are not the only conditions where inducing neuronal proliferation could be beneficial. Consequently, the impact of pro-proliferative compounds on neurons has also been researched in mouse models of Alzheimer's disease.

Cell-cycle arrest and mitochondria-dependent apoptosis induction in T-47D cells by the capsular polysaccharide from the marine bacterium Kangiella japonica KMM 3897

In this study, we reported the in vitro mechanisms of antiproliferative activity of capsular polysaccharide derived from marine Gram-negative bacteria Kangiella japonica KMM 3897 in human breast сarcinoma T-47D cells. Flow cytometric and Western blot analysis revealed that capsular polysaccharide effectively suppressed T-47D cell proliferation by inducing G0/G1 phase arrest and mitochondrial-dependent apoptosis. Moreover, polysaccharide influenced the ERK1/2 and p38 signaling pathways. The results of this study would enrich our understanding of the molecular mechanism of the anti-cancer activity of sulfated polysaccharides from marine Gram-negative bacteria.

Hepatocyte-derived exosomal miR-146a-5p inhibits hepatic stellate cell EMT process: a crosstalk between hepatocytes and hepatic stellate cells

Recently, Salidroside (Sal) has been demonstrated to suppress hepatic stellate cell (HSC) activation, a crucial event for liver fibrosis. Moreover, Sal has been reported to decrease hepatocyte injury. A growing number of reports have indicated that the crosstalk between hepatocytes and HSCs is very crucial for liver fibrosis development. Whether Sal-treated hepatocytes could inhibit HSC activation is unclear. Exosomes, as vital vehicles of intercellular communication, have been shown to transfer cargos between hepatocytes and HSCs. Herein, we aimed to investigate the roles of exosomal miRNAs from Sal-treated hepatocytes in HSC activation as well as liver fibrosis. Our results showed that Sal suppressed carbon tetrachloride (CCl4)-induced liver fibrosis in vivo. HSC activation as well as cell proliferation was repressed in HSCs co-cultured with Sal-treated hepatocytes. Interestingly, miR-146a-5p was up-regulated by Sal in CCl4-treated mice. Also, enhanced miR-146a-5p was found in hepatocytes isolated from Sal-treated CCl4 mice and hepatocyte-derived exosomes. Notably, hepatocyte exosomal miR-146a-5p contributed to HSC inactivation. Inhibiting miR-146a-5p in hepatocyte exosomes resulted in reduced E-cadherin (E-cad) and increased desmin in HSCs, indicating that miR-146a-5p caused HSC inactivation via epithelial-mesenchymal transition (EMT). miR-146a-5p inhibition-mediated HSC activation and EMT process were blocked down by loss of EIF5A2. Further studies revealed that EIF5A2 was a target of miR-146a-5p. Furthermore, exosomes with miR-146a-5p overexpression inhibited liver fibrosis in CCl4 mice. Collectively, exosomal miR-146a-5p from Sal-treated hepatocytes inhibits HSC activation and liver fibrosis, at least in part, by suppressing EIF5A2 and EMT process.

Secretory leukocyte protease inhibitor (SLPI) in cancer pathophysiology: Mechanisms of action and clinical implications

Cancer is a multifaceted disorder frequently linked to the dysregulation of several biological processes. The SLPI is a multifunctional protein involved in the modulation of immunological response and the inhibition of protease activities. SLPI acts as an inhibitor of proteases, exerts antibacterial properties, and suppresses the transcription of proinflammatory genes through the nuclear factor-kappa B (NF-κB) pathway. The role of this protein as a regulatory agent has been implicated in various types of cancer. Recent research has revealed that SLPI upregulation in cancer cells enhances the metastatic capacity of epithelial malignancies, indicating the deleterious effects of this protein. Furthermore, SLPI interacts intricately with other cancer-promoting factors, including matrix metalloproteinase-2 (MMP-2), MMP-9, the NF-κB and Akt pathways, and the p53-upregulated modulator of apoptosis (PUMA). This review provides an overview of the role of SLPI in cancer pathophysiology, emphasizing its expression in cancer cells and tissues, its potential as a prognostic biomarker, and its therapeutic promise as a target in cancer treatment. The mechanisms of SLPI action in cancer, including its anti-inflammatory effects, regulation of cell proliferation and angiogenesis, and modulation of the tumor microenvironment, have been investigated. The clinical implications of SLPI in cancer have been discussed, including its potential as a diagnostic and prognostic biomarker, its role in chemoresistance, and its therapeutic potential in several types of cancer, such as hepatocellular carcinoma (HCC), colorectal cancer (CRC), pancreatic cancer, head and neck squamous cell carcinoma (HNSCC), ovarian cancer (OvCa), prostate cancer (PC), gastric cancer (GC), breast cancer, and other cancers. In addition, we emphasized the significance of SLPI in cancer, which offers fresh perspectives on potential targets for cancer therapy.

Mast cells in colorectal cancer tumour progression, angiogenesis, and lymphangiogenesis

The characteristics of the tumour cells, as well as how tumour cells interact with their surroundings, affect the prognosis of cancer patients. The resident cells in the tumour microenvironment are mast cells (MCs), which are known for their functions in allergic responses, but their functions in the cancer milieu have been hotly contested. Several studies have revealed a link between MCs and the development of tumours. Mast cell proliferation in colorectal cancer (CRC) is correlated with angiogenesis, the number of lymph nodes to which the malignancy has spread, and patient prognosis. By releasing angiogenic factors (VEGF-A, CXCL 8, MMP-9, etc.) and lymphangiogenic factors (VEGF-C, VEGF-D, etc.) stored in granules, mast cells play a significant role in the development of CRC. On the other hand, MCs can actively encourage tumour development via pathways including the c-kit/SCF-dependent signaling cascade and histamine production. The impact of MC-derived mediators on tumour growth, the prognostic importance of MCs in patients with various stages of colorectal cancer, and crosstalk between MCs and CRC cells in the tumour microenvironment are discussed in this article. We acknowledge the need for a deeper comprehension of the function of MCs in CRC and the possibility that targeting MCs might be a useful therapeutic approach in the future.

Iodine-Biofortified Lettuce Can Promote Mitochondrial Dependent Pathway of Apoptosis in Human Gastrointestinal Cancer Cells

Previously, our research provided evidence that exposure of gastric and colon cancer cells to extracts from iodine-biofortified lettuce leads to a reduction of cell viability and proliferation through cell cycle arrest and upregulation of pro-apoptotic genes. The aim of the present study was to determine the potential cellular mechanisms of induction of cell death in human gastrointestinal cancer cell lines after treatment with iodine-biofortified lettuce. We demonstrated that extracts from lettuce enriched with iodine induce apoptosis in gastric AGS and colon HT-29 cancer cells and the mechanism of programmed cell death may be triggered and executed through different signaling pathways, depending on the type of cells. Western blot analysis revealed that iodine-fortified lettuce leads to cell death through the release of cytochrome c to the cytosolic fraction and activation of the primary drivers of apoptosis: caspase-3, caspase-7, and caspase-9. Furthermore, we have reported that apoptotic effects of lettuce extracts may be mediated by poly (ADP-ribose) polymerase (PARP) and activation of pro-apoptotic Bcl-2 family proteins such as Bad, Bax, and BID. We also observed mitochondrial dysfunction with the dissipation of the mitochondrial membrane potential in cells exposed to lettuce extracts. Taken together, these results indicate that the organic form of iodine such as 5-ISA and 3,5-diISA is an important factor in the activation of intrinsic mitochondrial apoptotic pathway in AGS and HT-29 cancer cells in a p53-independent manner.

Targeting the p53 signaling pathway in cancers: Molecular mechanisms and clinical studies

Tumor suppressor p53 can transcriptionally activate downstream genes in response to stress, and then regulate the cell cycle, DNA repair, metabolism, angiogenesis, apoptosis, and other biological responses. p53 has seven functional domains and 12 splice isoforms, and different domains and subtypes play different roles. The activation and inactivation of p53 are finely regulated and are associated with phosphorylation/acetylation modification and ubiquitination modification, respectively. Abnormal activation of p53 is closely related to the occurrence and development of cancer. While targeted therapy of the p53 signaling pathway is still in its early stages and only a few drugs or treatments have entered clinical trials, the development of new drugs and ongoing clinical trials are expected to lead to the widespread use of p53 signaling-targeted therapy in cancer treatment in the future. TRIAP1 is a novel p53 downstream inhibitor of apoptosis. TRIAP1 is the homolog of yeast mitochondrial intermembrane protein MDM35, which can play a tumor-promoting role by blocking the mitochondria-dependent apoptosis pathway. This work provides a systematic overview of recent basic research and clinical progress in the p53 signaling pathway and proposes that TRIAP1 is an important therapeutic target downstream of p53 signaling.

AKR1B1 Represses Glioma Cell Proliferation through p38 MAPK-Mediated Bcl-2/BAX/Caspase-3 Apoptotic Signaling Pathways

This study aimed to investigate the regulatory role of Aldo-keto reductase family 1 member B1 (AKR1B1) in glioma cell proliferation through p38 MAPK activation to control Bcl-2/BAX/caspase-3 apoptosis signaling. AKR1B1 expression was quantified in normal human astrocytes, glioblastoma multiforme (GBM) cell lines, and normal tissues by using quantitative real-time polymerase chain reaction. The effects of AKR1B1 overexpression or knockdown and those of AKR1B1-induced p38 MAPK phosphorylation and a p38 MAPK inhibitor (SB203580) on glioma cell proliferation were determined using an MTT assay and Western blot, respectively. Furthermore, the AKR1B1 effect on BAX and Bcl-2 expression was examined in real-time by Western blot. A luminescence detection reagent was also utilized to identify the effect of AKR1B1 on caspase-3/7 activity. The early and late stages of AKR1B1-induced apoptosis were assessed by performing Annexin V-FITC/PI double-staining assays. AKR1B1 expression was significantly downregulated in glioma tissues and GBM cell lines (T98G and 8401). Glioma cell proliferation was inhibited by AKR1B1 overexpression but was slightly increased by AKR1B1 knockdown. Additionally, AKR1B1-induced p38 MAPK phosphorylation and SB203580 reversed AKR1B1's inhibitory effect on glioma cell proliferation. AKR1B1 overexpression also inhibited Bcl-2 expression but increased BAX expression, whereas treatment with SB203580 reversed this phenomenon. Furthermore, AKR1B1 induced caspase-3/7 activity. The induction of early and late apoptosis by AKR1B1 was confirmed using an Annexin V-FITC/PI double-staining assay. In conclusion, AKR1B1 regulated glioma cell proliferation through the involvement of p38 MAPK-induced BAX/Bcl-2/caspase-3 apoptosis signaling. Therefore, AKR1B1 may serve as a new therapeutic target for glioma therapy development.

Comparison of Human Eukaryotic Translation Initiation Factors 5A1 and 5AL1: Identification of Amino Acid Residues Important for EIF5A1 Lysine 50 Hypusination and Its Protein Stability

The human eukaryotic translation initiation factor 5A (EIF5A) family consists of three members, namely EIF5A1, EIF5A2, and EIF5AL1. Recent studies have shown that the expression of EIF5As is related to many human diseases, such as diabetes, viral infection, central nervous system injury, and cancer. Among them, EIF5A1 plays different functions in various cancers, possibly as a tumor-suppressor or oncogene, while EIF5A2 promotes the occurrence and development of cancer. Yet, the biological function of EIF5AL1 is not being studied so far. Interestingly, although there are only three amino acid (at residues 36, 45, and 109) differences between EIF5A1 and EIF5AL1, we demonstrate that only EIF5A1 can be hypusinated while EIF5AL1 cannot, and EIF5AL1 has a tumor-suppressor-like function by inhibiting cell proliferation and migration. We also show that EIF5AL1 protein turnover is mediated through the proteasomal pathway, and EIF5AL1 protein turnover is much faster than that of EIF5A1, which may explain their differential protein expression level in cells. By engineering single and double mutations on these three amino acids, we pinpoint which of these amino acids are critical for hypusination and protein stability. The data of this work should fill in the gaps in EIF5As research and pave the way for future studies on EIF5AL1.

Sex differences in the inflammatory response of the mouse DRG and its connection to pain in experimental autoimmune encephalomyelitis

Multiple Sclerosis (MS) is an autoimmune disease with notable sex differences. Women are not only more likely to develop MS but are also more likely than men to experience neuropathic pain in the disease. It has been postulated that neuropathic pain in MS can originate in the peripheral nervous system at the level of the dorsal root ganglia (DRG), which houses primary pain sensing neurons (nociceptors). These nociceptors become hyperexcitable in response to inflammation, leading to peripheral sensitization and eventually central sensitization, which maintains pain long-term. The mouse model experimental autoimmune encephalomyelitis (EAE) is a good model for human MS as it replicates classic MS symptoms including pain. Using EAE mice as well as naïve primary mouse DRG neurons cultured in vitro, we sought to characterize sex differences, specifically in peripheral sensory neurons. We found sex differences in the inflammatory profile of the EAE DRG, and in the TNFα downstream signaling pathways activated intracellularly in cultured nociceptors. We also found increased cell death with TNFα treatment. Given that TNFα signaling has been shown to initiate intrinsic apoptosis through mitochondrial disruption, this led us to investigate sex differences in the mitochondria's response to TNFα. Our results demonstrate that male sensory neurons are more sensitive to mitochondrial stress, making them prone to neuronal injury. In contrast, female sensory neurons appear to be more resistant to mitochondrial stress and exhibit an inflammatory and regenerative phenotype that may underlie greater nociceptor hyperexcitability and pain. Understanding these sex differences at the level of the primary sensory neuron is an important first step in our eventual goal of developing sex-specific treatments to halt pain development in the periphery before central sensitization is established.

Intravenous Immunoglobulin Inhibits Liver Cancer Progression by Promoting p38MAPK-Associated Apoptosis

OBJECTIVE

The aim of this study is to explore the effect of intravenous immunoglobulin (IVIG) on the development of rat hepatocellular carcinoma and its possible molecular mechanism.

METHODS

Sixty adult male Sprague-Dawley (SD) rats were randomly divided into three groups: control, diethylnitrosamine(DEN) + normal saline(NS), and DEN + IVIG groups, with 20 rats in each group. The  rats in the DEN + NS group and DEN + IVIG group were given DEN 0.2 g/kg intraperitoneal injection once on day 1 and then 0.05% DEN aqueous solution in drinking water to establish a rat liver cancer model. Immunoglobulin (IgG) was injected intraperitoneally into the DEN + IVIG group twice a week at the dose of 100 mg/kg, and saline was administered intraperitoneally into the control group at a 50 mg/kg dosage. The body weight of each group of rats was recorded twice a week. All treatments were maintained continuously for 12 weeks. After the intervention, the liver function indexes of rats were measured by a fully automated biochemical analysis instrument. The liver histopathology was observed by hematoxylin-eosin(HE) staining. Immunohistochemistry was used to detect c-myc protein expression, and Western blotting was used to determine p38MAPK and p-p38MAPK protein expressions, as well as apoptosis-related proteins such as Bcl-2, Bax, and cleaved caspase-3.

RESULTS

Compared with the rats in the DEN + NS group, rats in the DEN + IVIG group showed substantially higher body mass (P < 0.05), higher survival rate (P < 0.05), and lower liver function indexes (P < 0.05). Few focal necrosis of cancer cells and few nuclear division were observed in the rats in the DEN + IVIG group. The rats in the DEN + NS group showed lamellar necrosis of cancer foci, destruction of normal liver lobular structure, and hepatocellular carcinoma cells. Immunohistochemical analysis results revealed that the expression of c-myc was reduced in the DEN + IVIG group (P < 0.05), and Western blotting confirmed that the Bcl-2 expression was decreased (P < 0.05), while Bax, p38 MAPK, p-p38 MAPK, and cleaved caspase-3 protein expressions were increased (P < 0.05).

CONCLUSION

IVIG prophylactic injection can delay tumor development and induce apoptosis in primary hepatocellular carcinoma in rats. The mechanism is connected to the activation of the p38MAPK signaling pathway by upregulating the level of cleaved caspase-3 and Bax proteins while downregulating the level of Bcl-2 and c-myc proteins.

Green tea-derived theabrownin suppresses human non-small cell lung carcinoma in xenograft model through activation of not only p53 signaling but also MAPK/JNK signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

According to the theory and practice of traditional Chinese medicine (TCM), the pathogenesis of lung carcinoma is associated with many syndromes, such as "sputum stasis", "cough", "lung fever", "lung toxin", and "hemoptysis", which should be removed for therapeutic purpose. Tea is not only a world-wide beverage, but also a TCM herb, possessing activities against the above syndromes. Recently, green tea extract exerted inhibitory effects on a variety of tumor cells. As a pigment active substance of green tea, theabrownin (TB) has been found to inhibit many cancer cells.

AIM OF THE STUDY

This study focused on the efficacy and mechanism of TB on non-small cell lung cancer (NSCLC) cell lines. The in vivo efficacy of TB on p53-deficient NSCLC (H1299) cells and p53-wild type NSCLC (A549) cells NSCLC cells were determined, and its mechanism of action was explored.

MATERIALS AND METHODS

In vivo, two lung cancer cell lines, H1299 (p53-deficient) and A549 (p53-wild type) were selected to establish xenograft models of larval zebrafish, respectively. For in vitro experiments, wound healing assay, DAPI staining, TUNEL assay, immunofluorescence assay, and flow cytometry were conducted in these two cell lines. RNA sequencing (RNAseq), real time PCR (qPCR) and Western blot (WB) were performed for the mechanism study.

RESULTS

The in vivo results showed that TB significantly inhibited the H1299 and the A549 xenograft tumor growth in larval zebrafish (dosage ranged from 2.13 to 21.3 μg/ml). Wound healing assay results showed that TB suppressed the migration of H1299 cells. DAPI staining, TUNEL assay, and immunofluorescence assay results showed that TB inhibited the growth of H1299 cells by inducing apoptosis. RNAseq, qPCR and WB data showed that TB significantly up-regulated the MAPK/JNK pathway-related proteins (ASK-1, JNK and c-JUN) through phosphorylation activation, accompanying with down-regulation of the epithelial-mesenchymal transition (EMT)-associated genes (N-CADHERIN, SLUG, FIBROWNECTIN and ZEB1) and anti-apoptotic molecules (BCL-2), and up-regulation of the metastasis-related gene HSPA6 and the pro-apoptotic molecules (BIM, BAX, PARP, c-PARP, γ-H2A.X, c-CASP3, c-CASP8, c-CASP9, DDIT3 and DUSP8).

CONCLUSION

This study determined the in vivo efficacy of green tea-derived TB on p53-deficient NSCLC (H1299) cells and p53-wild type NSCLC (A549) cells and clarified its p53-independent mechanism mediated by the activation of MAPK/JNK signaling pathway.

Combined Transcriptomic and Proteomic Profiling to Unravel Osimertinib, CARP-1 Functional Mimetic (CFM 4.17) Formulation and Telmisartan Combo Treatment in NSCLC Tumor Xenografts

The epidermal growth factor receptor (EGFR) is highly expressed in many non-small cell lung cancers (NSCLC), necessitating the use of EGFR-tyrosine kinase inhibitors (TKIs) as first-line treatments. Osimertinib (OSM), a third-generation TKI, is routinely used in clinics, but T790M mutations in exon 20 of the EGFR receptor lead to resistance against OSM, necessitating the development of more effective therapeutics. Telmisartan (TLM), OSM, and cell cycle and apoptosis regulatory protein 1 (CARP-1) functional mimetic treatments (CFM4.17) were evaluated in this study against experimental H1975 tumor xenografts to ascertain their anti-cancer effects. Briefly, tumor growth was studied in H1975 xenografts in athymic nude mice, gene and protein expressions were analyzed using next-generation RNA sequencing, proteomics, RT-PCR, and Western blotting. TLM pre-treatment significantly reduced the tumor burden when combined with CFM-4.17 nanoformulation and OSM combination (TLM_CFM-F_OSM) than their respective single treatments or combination of OSM and TLM with CFM 4.17. Data from RNA sequencing and proteomics revealed that TLM_CFM-F_OSM decreased the expression of Lamin B2, STAT3, SOD, NFKB, MMP-1, TGF beta, Sox-2, and PD-L1 proteins while increasing the expression of AMPK proteins, which was also confirmed by RT-PCR, proteomics, and Western blotting. According to our findings, the TLM_CFM-F_OSM combination has a superior anti-cancer effect in the treatment of NSCLC by affecting multiple resistant markers that regulate mitochondrial homeostasis, inflammation, oxidative stress, and apoptosis.

SLPI suppresses hepatocellular carcinoma progression via endoplasmic reticulum stress induced apoptosis

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. Secretory leukocyte protease inhibitor (SLPI) has been reported to function as a regulatory factor in several cancers. However, its biological functions and underlying mechanisms in HCC remain to be uncovered. Here, we aimed to explore the effect of SLPI in HCC. In our study, we found that the mRNA and protein expression levels of SLPI were significantly down-regulated in HCC tissues and hepatoma cell lines and low level of SLPI predicted worse survival in our HCC cohorts. In term of function, silencing of SLPI markedly promoted whereas overexpression SLPI suppressed proliferation, migration and invasion capabilities of HCC cells in vitro, and ectopic expression of SLPI inhibited the tumorigenicity of HCC cells in vivo. Mechanistic studies demonstrated that SLPI played a protective role in HCC progression via activating endoplasmic reticulum stress (ER stress)-mediated apoptosis of hepatoma cells, which could be regulated by MAPK signaling pathways. In summary, our findings highlight that SLPI could serve as a potential prognostic biomarker and putative tumor suppressor by enhancing ER stress-induced apoptosis in HCC cells mediated by MAPK signaling pathways, which provides new insights into promising therapeutic targets for HCC treatment.

TNFα in MS and Its Animal Models: Implications for Chronic Pain in the Disease

Multiple Sclerosis (MS) is a debilitating autoimmune disease often accompanied by severe chronic pain. The most common type of pain in MS, called neuropathic pain, arises from disease processes affecting the peripheral and central nervous systems. It is incredibly difficult to study these processes in patients, so animal models such as experimental autoimmune encephalomyelitis (EAE) mice are used to dissect the complex mechanisms of neuropathic pain in MS. The pleiotropic cytokine tumor necrosis factor α (TNFα) is a critical factor mediating neuropathic pain identified by these animal studies. The TNF signaling pathway is complex, and can lead to cell death, inflammation, or survival. In complex diseases such as MS, signaling through the TNFR1 receptor tends to be pro-inflammation and death, whereas signaling through the TNFR2 receptor is pro-homeostatic. However, most TNFα-targeted therapies indiscriminately block both arms of the pathway, and thus are not therapeutic in MS. This review explores pain in MS, inflammatory TNF signaling, the link between the two, and how it could be exploited to develop more effective TNFα-targeting pain therapies.

Stress sensing within the breast tumor microenvironment: how glucocorticoid receptors live in the moment

The classification and treatment of breast cancer is largely defined by the expression of steroid hormone receptors (HRs), namely estrogen receptor (ER) and progesterone receptor (PR), and gene amplification/overexpression of human epidermal growth factor receptor 2 (HER2). More recently, studies of androgen receptor (AR), glucocorticoid receptor (GR), and mineralocorticoid receptor (MR) have revealed that targeting these related HRs may be a promising strategy for a more personalized approach to the treatment of specific subtypes of HR+ breast cancer. For example, GR expression is associated with a good prognosis in ER+ breast cancer, but predicts poor prognosis in triple-negative breast cancer (TNBC). GR, like ER, PRs, and AR, is a ligand-activated transcription factor, but also has significant ligand-independent signaling activities. GR transcriptional activity is classically regulated by circulating glucocorticoids (GCs; ligand-dependent). Recent studies demonstrate that GR transcriptional activity is also regulated by a variety of cellular stress stimuli that input to GR Ser134 phosphorylation via rapid activation of the p38 mitogen activated protein kinase (MAPK) signaling pathway (ligand-independent). Furthermore, ligand-independent GR activation promotes feedforward signaling loops that mediate sustained activation of stress signaling pathways to drive advanced cancer biology (i.e. migration, invasion, chemoresistance, survival, and cellular growth). In this review, we will focus on the role of GR as a key sensor and mediator of physiologic and tumor microenvironment (TME)-derived cellular stress signaling in TNBC and discuss how targeting GR and/or associated signaling pathways may provide a strategy to inhibit deadly TNBC progression.

Uncovering drug repurposing candidates for head and neck cancers: insights from systematic pharmacogenomics data analysis

Effective treatment options for head and neck squamous cell carcinoma (HNSCC) are currently lacking. We exploited the drug response and genomic data of the 28 HNSCC cell lines, screened with 4,518 compounds, from the PRISM repurposing dataset to uncover repurposing drug candidates for HNSCC. A total of 886 active compounds, comprising of 418 targeted cancer, 404 non-oncology, and 64 chemotherapy compounds were identified for HNSCC. Top classes of mechanism of action amongst targeted cancer compounds included PI3K/AKT/MTOR, EGFR, and HDAC inhibitors. We have shortlisted 36 compounds with enriched killing activities for repurposing in HNSCC. The integrative analysis confirmed that the average expression of EGFR ligands (AREG, EREG, HBEGF, TGFA, and EPGN) is associated with osimertinib sensitivity. Novel putative biomarkers of response including those involved in immune signalling and cell cycle were found to be associated with sensitivity and resistance to MEK inhibitors respectively. We have also developed an RShiny webpage facilitating interactive visualization to fuel further hypothesis generation for drug repurposing in HNSCC. Our study provides a rich reference database of HNSCC drug sensitivity profiles, affording an opportunity to explore potential biomarkers of response in prioritized drug candidates. Our approach could also reveal insights for drug repurposing in other cancers.

Understanding Abnormal c-JNK/p38MAPK Signaling in Amyotrophic Lateral Sclerosis: Potential Drug Targets and Influences on Neurological Disorders

c-JNK (c-Jun N-terminal kinase) and p38 mitogen-activated protein kinase (MAPK) family members work in a cell-specific manner to regulate neuronal signals. The abnormal activation of these cellular signals can cause glutamate excitotoxicity, disrupted protein homeostasis, defective axonal transport, and synaptic dysfunction. Various pre-clinical and clinical findings indicate that the up-regulation of c-JNK and p38MAPK signaling is associated with neurological disorders. Exceptionally, a significant amount of experimental data has recently shown that dysregulated c-JNK and p38MAPK are implicated in the damage to the central nervous system, including amyotrophic lateral sclerosis. Furthermore, currently available information has shown that c- JNK/p38MAPK signaling inhibitors may be a promising therapeutic alternative for improving histopathological, functional, and demyelination defects related to motor neuron disabilities. Understanding the abnormal activation of c-JNK/p38MAPK signaling and the prediction of motor neuron loss may help identify important therapeutic interventions that could prevent neurocomplications. Based on the involvement of c-JNK/p38MAPK signaling in the brain, we have assumed that the downregulation of the c-JNK/p38MAPK signaling pathway could trigger neuroprotection and neurotrophic effects towards clinicopathological presentations of ALS and other brain diseases. Thus, this research-based review also outlines the inhibition of c-JNK and p38MAPK signal downregulation in the pursuit of disease-modifying therapies for ALS.

Nrf2 overexpression increases risk of high tumor mutation burden in acute myeloid leukemia by inhibiting MSH2

Nuclear factor erythroid 2-related factor 2 (Nrf2, also called NFE2L2) plays an important role in cancer chemoresistance. However, little is known about the role of Nrf2 in tumor mutation burden and the effect of Nrf2 in modulating DNA mismatch repair (MMR) gene in acute myeloid leukemia (AML). Here we show that Nrf2 expression is associated with tumor mutation burden in AML. Patients with Nrf2 overexpression had a higher frequency of gene mutation and drug resistance. Nrf2 overexpression protected the AML cells from apoptosis induced by cytarabine in vitro and increased the risk of drug resistance associated with a gene mutation in vivo. Furthermore, Nrf2 overexpression inhibited MutS Homolog 2 (MSH2) protein expression, which caused DNA MMR deficiency. Mechanistically, the inhibition of MSH2 by Nrf2 was in a ROS-independent manner. Further studies showed that an increased activation of JNK/c-Jun signaling in Nrf2 overexpression cells inhibited the expression of the MSH2 protein. Our findings provide evidence that high Nrf2 expression can induce gene instability-dependent drug resistance in AML. This study demonstrates the reason why the high Nrf2 expression leads to the increase of gene mutation frequency in AML, and provides a new strategy for clinical practice.

The effect of streptozotocin induced diabetes on sperm function: a closer look at AGEs, RAGEs, MAPKs and activation of the apoptotic pathway

This study was designed to (1) investigate the possible mechanisms through which diabetes-induced advanced glycation end products (AGEs) and receptor for AGEs (RAGE) activation can affect male reproductive function; and (2) corroborate the interaction of previously established independent pathways. Male albino Wistar rats (14-weeks old) weighing 250-300 g received either a single intraperitoneal injection of streptozotocin (30 mg/kg or 60 mg/kg), represented as STZ30 or STZ60 respectively, or citrate buffer (control). Diabetes mellitus (DM) was confirmed if plasma glucose levels were ≥ 14 mmol/L after 1 week. Animals were sacrificed after 8 weeks of treatment by an overdose of sodium pentobarbital (160 mg/kg body weight). The testes and epididymides were harvested. The testes were used for biochemical and Western blot analysis, while sperm was retrieved from the epididymis and analysed with computer-aided sperm analysis. The blood glucose levels of STZ60 animals were above the cut-off point and hence these animals were regarded as diabetic. Diabetic animals presented with a non-significant increase in AGE and RAGE expression. Diabetic animals showed a significant increase in the expression of cleaved caspase 3 compared to control (p < 0.001), and these animals also presented with an increase in the expression of JNK (p < 0.05), PARP (p = 0.059) and p38 MAPK (p = 0.1). Diabetic animals also displayed decreased catalase activity accompanied by a non-significant increase in malondialdehyde levels. Additionally, there was a significant decrease in the percentage of progressively motile spermatozoa (p < 0.05) in diabetic animals. This study has shed some light on the interplay between DM, AGE, RAGE and mitogen-activated protein kinase signalling in the testes of diabetic rats, which can result in altered sperm function and contribute to male infertility. However, more studies are needed to better understand this complicated process.

RPS4Y1 Promotes High Glucose-Induced Endothelial Cell Apoptosis and Inflammation by Activation of the p38 MAPK Signaling

AIM

Endothelial dysfunction is a key pathological basis for diabetes mellitus complications, including diabetic nephropathy, diabetic retinopathy, and diabetic cardiomyopathy. This study aimed to reveal the functional role of ribosomal protein S4 Y-linked 1 (RPS4Y1) in endothelial dysfunction.

METHODS

Human umbilical vein endothelial cells (HUVECs) were subjected to high glucose. The expression of RPS4Y1 in cells was overexpressed or silenced by plasmid or siRNA transfection. MTT assay, flow cytometry, JC-1 probe, scratch test, tube formation, and ELISA were conducted to assess the effects of RPS4Y1 on cell. Western blot was performed to assay the downstream signaling of RPS4Y1. The inhibitors of p38, ERK, and Jnk were used to treat cells to validate the involvement of them in RPS4Y1-mediated endothelial dysfunction.

RESULTS

RPS4Y1 was upregulated in HUVECs in response to high glucose in both dose- and time-dependent manners. Overexpression of RPS4Y1 induced viability loss, apoptosis, and inflammation, but inhibited cell migration and tube formation. Silence of RPS4Y1 impacted these aspects in a contrary trend. The phosphorylation of p38 rather than ERK and Jnk was activated by RPS4Y1. In addition, the dysfunction of HUVECs mediated by RPS4Y1 was attenuated by SB203580 (a specific inhibitor of p38 signaling).

CONCLUSION

The highly expressed RPS4Y1 in endothelial cells may contribute to high glucose-induced dysfunction through regulating p38 MAPK signaling. RPS4Y1 might be a potential therapeutic target for treating diabetes mellitus complications.

Knockdown of eukaryotic translation initiation factor 5A2 enhances the therapeutic efficiency of doxorubicin in hepatocellular carcinoma cells by triggering lethal autophagy

Hepatocellular carcinoma (HCC) is an invasive malignant neoplasm with a poor prognosis. The development of chemoresistance severely obstructs the chemotherapeutic efficiency of HCC treatment. Therefore, understanding the mechanisms of chemoresistance is important for improving the outcomes of patients with HCC. Eukaryotic translation initiation factor 5A2 (eIF5A2), which is considered to be an oncogene, has been reported to mediate chemoresistance in various types of cancer; however, its precise role in HCC remains unclear. Accumulating evidence has suggested that autophagy serves a dual role in cancer chemotherapy. The present study aimed to investigate the role of autophagy in eIF5A2‑mediated doxorubicin resistance in HCC. High expression levels of eIF5A2 in human HCC tissues were observed by immunohistochemistry using a tissue microarray, which was consistent with the results of reverse transcription‑quantitative PCR analysis in paired HCC and adjacent healthy tissues. HCC patient‑derived tumor xenograft mouse model was used for the in vivo study, and knockdown of eIF5A2 effectively enhanced the efficacy of doxorubicin chemotherapy compared with that in the control group. Notably, eIF5A2 served as a repressor in regulating autophagy under chemotherapy. Silencing of eIF5A2 induced doxorubicin sensitivity in HCC cells by triggering lethal autophagy. In addition, 5‑ethynyl‑2'‑deoxyuridine, lactate dehydrogenase release assay and calcein‑AM/PI staining were used to determine the enhanced autophagic cell death induced by the silencing of eIF5A2 under doxorubicin treatment. Suppression of autophagy attenuated the sensitivity of HCC cells to doxorubicin induced by eIF5A2 silencing. The results also demonstrated that knockdown of the Beclin 1 gene, which is an autophagy regulator, reversed the enhanced autophagic cell death and doxorubicin sensitivity induced by eIF5A2 silencing. Taken together, these results suggested eIF5A2 may mediate the chemoresistance of HCC cells by suppressing autophagic cell death under chemotherapy through a Beclin 1‑dependent pathway, and that eIF5A2 may be a novel potential therapeutic target for HCC treatment.

Long non-coding RNA 01126 promotes periodontitis pathogenesis of human periodontal ligament cells via miR-518a-5p/HIF-1α/MAPK pathway

Background

Periodontitis is a prevalent oral inflammatory disease, which can cause periodontal ligament to a local hypoxia environment. However, the mechanism of hypoxia associated long non‐coding RNAs (lncRNAs) involved in periodontitis is still largely unknown.

Methods

Microarray was performed to detect the expression patterns of lncRNAs in 3 pairs of gingival tissues from patients with periodontitis and healthy controls. The expression of lncRNA 01126 (LINC01126), miR‐518a‐5p and hypoxia‐inducible factor‐1α (HIF‐1α) in periodontal tissues and in human periodontal ligament cells (hPDLCs) under hypoxia was measured by quantitative real‐time polymerase chain reaction or western blot. Fluorescence in situ hybridization and cell fraction assay were performed to determine the subcellular localization of LINC01126 and miR‐518a‐5p. Overexpression or knockdown of LINC01126 or HIF‐1α was used to confirm their biological roles in hPDLCs. MTT assays were performed to evaluate hPDLCs proliferation ability. Flow cytometry was used to detect apoptosis. ELISA was used to measure the expression levels of interleukin (IL)‐1β, IL‐6, IL‐8 and TNF‐α. Dual‐luciferase reporter assays were performed to assess the binding of miR‐518a‐5p to LINC01126 and HIF‐1α. RNA immunoprecipitation assay was used to identify whether LINC01126 and miR‐518a‐5p were significantly enriched in AGO‐containing micro‐ribonucleoprotein complexes.

Results

We selected LINC01126, which was the most highly expressed lncRNA, to further verify its functions in periodontitis‐induced hypoxia. The expression of LINC01126 was increased in periodontal tissues. In vitro experiment demonstrated that LINC01126 suppressed proliferation, promoted apoptosis and inflammation of hPDLCs under hypoxia via sponging miR‐518a‐5p. Moreover, we identified HIF‐1α acted as a direct target of miR‐518a‐5p in hPDLCs and LINC01126 promoted periodontitis pathogenesis by regulating the miR‐518a‐5p/HIF‐1α/MAPK pathway.

Conclusion

LINC01126 promotes periodontitis pathogenesis of hPDLCs via miR‐518a‐5p/HIF‐1α/MAPK pathway, providing a possible clue for LINC01126‐based periodontal therapeutic approaches.

NR4A1 counteracts JNK activation incurred by ER stress or ROS in pancreatic β-cells for protection

Sustained hyperglycaemia and hyperlipidaemia incur endoplasmic reticulum stress (ER stress) and reactive oxygen species (ROS) overproduction in pancreatic β‐cells. ER stress or ROS causes c‐Jun N‐terminal kinase (JNK) activation, and the activated JNK triggers apoptosis in different cells. Nuclear receptor subfamily 4 group A member 1 (NR4A1) is an inducible multi‐stress response factor. The aim of this study was to explore the role of NR4A1 in counteracting JNK activation induced by ER stress or ROS and the related mechanism. qPCR, Western blotting, dual‐luciferase reporter and ChIP assays were applied to detect gene expression or regulation by NR4A1. Immunofluorescence was used to detect a specific protein expression in β‐cells. Our data showed that NR4A1 reduced the phosphorylated JNK (p‐JNK) in MIN6 cells encountering ER stress or ROS and reduced MKK4 protein in a proteasome‐dependent manner. We found that NR4A1 increased the expression of cbl‐b (an E3 ligase); knocking down cbl‐b expression increased MKK4 and p‐JNK levels under ER stress or ROS conditions. We elucidated that NR4A1 enhanced the transactivation of cbl‐b promoter by physical association. We further confirmed that cbl‐b expression in β‐cells was reduced in NR4A1‐knockout mice compared with WT mice. NR4A1 down‐regulates JNK activation by ER stress or ROS in β‐cells via enhancing cbl‐b expression.

Eukaryotic translation initiation factor 5A in the pathogenesis of cancers

Cancer is the leading cause of death worldwide. The absence of obvious symptoms and insufficiently sensitive biomarkers in early stages of carcinoma limits early diagnosis. Cancer therapy agents and targeted therapy have been used extensively against tissues or organs of specific cancers. However, the intrinsic and/or acquired resistance to the agents or targeted drugs as well as the serious toxic side effects of the drugs would limit their use. Therefore, identifying biomarkers involved in tumorigenesis and progression represents a challenge for cancer diagnosis and therapeutic strategy development. The eukaryotic translation factor 5A (eIF5A), originally identified as an initiation factor, was later shown to promote translation elongation of iterated proline sequences. There are two eIF5A isoforms (eIF5A1 and eIF5A2). eIF5A2 protein consists of 153 residues, and shares 84% amino acid identity with eIF5A1. However, the biological functions of these two isoforms may be significantly different. Recently, it was demonstrated that eIF5Ais widely involved in the pathogenesis of a number of diseases, including cancers. In particular, eIF5A plays an important role in regulating tumor growth, invasion, metastasis and tumor microenvironment. It was also shown to serve as a potential biomarker and target for the diagnosis and treatment of cancers. The present review briefly discusses the latest findings of eIF5A in the pathogenesis of certain malignant cancers and evolving clinical applications.

Propranolol induced apoptosis and autophagy via the ROS/JNK signaling pathway in Human Ovarian Cancer

Propranolol has a significant anti-cancer effect towards various cancers. Our study aimed at investigating the underlying mechanism of Propranolol's therapeutic effect towards ovarian cancer. Specifically, Propranolol significantly reduced the viability of human ovarian cancer cell lines SKOV-3 and A2780 in a dose- and time-dependent manner. Flow cytometry analysis revealed that Propranolol induced the cell cycle arrest at G2/M phase therefore leading to apoptosis. Moreover, autophagy inhibitor 3-MA markedly enhanced the Propranolol-induced apoptosis. In addition, reactive oxygen species (ROS) increased dramatically after Propranolol treatment and Propranolol activated the phosphorylation of JNK. What is more, p38 inhibitor SB203580 and JNK inhibitor SP600125 attenuated the upregulated expression of LC3-II and cleaved-caspase-3 by the effect of Propranolol. ROS exclusive inhibitor antioxidant N-acetyl cysteine (NAC) weakens the phosphorylation of JNK proteins induced by Propranolol. In summary, these results suggested that Propranolol induced cell apoptosis and protective autophagy through the ROS/JNK signaling pathway in human ovarian cancer cells.

Cilostazol alleviate nicotine induced cardiomyocytes hypertrophy through modulation of autophagy by CTSB/ROS/p38MAPK/JNK feedback loop

Nicotine is proved to be an important factor for cardiac hypertrophy. Autophagy is important cell recycling system involved in the regulation of cardiac hypertrophy. Cilostazol, which is often used in the management of peripheral vascular disease. However, the effects of cilostazol on nicotine induced autophagy and cardiac hypertrophy are unclear. Here, we aim to determine the role and molecular mechanism of cilostazol in alleviating nicotine-induced cardiomyocytes hypertrophy through modulating autophagy and the underlying mechanisms. Our results clarified that nicotine stimulation caused cardiomyocytes hypertrophy and autophagy flux impairment significantly in neonatal rat ventricular myocytes (NRVMs), which were evidenced by augments of LC3-II and p62 levels, and impaired autophagosomes clearance. Interestingly, cathepsin B (CTSB) activity decreased dramatically after stimulation with nicotine in NRVMs, which was crucial for substrate degradation in the late stage of autophagy process, and cilostazol could reverse this effect dramatically. Intracellular ROS levels were increased significantly after nicotine exposure. Meanwhile, p38MAPK and JNK were activated after nicotine treatment. By using ROS scavenger N-acetyl-cysteine (NAC) could reverse the effects of nicotine by down-regulation the phosphorylation of p38MAPK and JNK pathways, and pretreatment of specific inhibitors of p38MAPK and JNK could restore the autophagy impairment and cardiomyocytes hypertrophy induced by nicotine. Moreover, CTSB activity of lysosome regained after the treatment with cilostazol. Cilostazol also inhibited the ROS accumulation and the activation of p38MAPK and JNK, which providing novel connection between lysosome CTSB and ROS/p38MAPK/JNK related oxidative stress pathway. This is the first demonstration that cilostazol could alleviate nicotine induced cardiomyocytes hypertrophy through restoration of autophagy flux by activation of CTSB and inhibiting ROS/p38/JNK pathway, exhibiting a feedback loop on regulation of autophagy and cardiomyocytes hypertrophy.

Understanding MAPK Signaling Pathways in Apoptosis

MAPK (mitogen-activated protein kinase) signaling pathways regulate a variety of biological processes through multiple cellular mechanisms. In most of these processes, such as apoptosis, MAPKs have a dual role since they can act as activators or inhibitors, depending on the cell type and the stimulus. In this review, we present the main pro- and anti-apoptotic mechanisms regulated by MAPKs, as well as the crosstalk observed between some MAPKs. We also describe the basic signaling properties of MAPKs (ultrasensitivity, hysteresis, digital response), and the presence of different positive feedback loops in apoptosis. We provide a simple guide to predict MAPKs’ behavior, based on the intensity and duration of the stimulus. Finally, we consider the role of MAPKs in osmostress-induced apoptosis by using Xenopus oocytes as a cell model. As we will see, apoptosis is plagued with multiple positive feedback loops. We hope this review will help to understand how MAPK signaling pathways engage irreversible cellular decisions.

Radix Sophorae Flavescentis induces apoptosis through by Caspase, MAPK Activation and ROS Signaling Pathways in 5637 Human Bladder Cancer Cells

The anti-cancer mechanisms of Radix Sophorae Flavescentis were investigated in 5637 bladder cancer cells. Radix Sophorae Flavescentis extract (RSF) (50‑400 µg/ml) inhibited the proliferation of 5637 cells and increased sub‑G1 phase ratios. RSF‑induced cell death was associated with the down-regulation of B‑cell lymphoma 2 (Bcl‑2) and the up-regulation of Bcl‑2 X‑associated protein (Bax). RSF also activated caspase‑3 and -9 and regulated the activations of mitogen-activated protein kinases (MAPKs). In addition, RSF increased intracellular reactive oxygen species (ROS) levels and depolarized the mitochondrial membrane potential. These findings suggest RSF induces apoptosis in 5637 bladder cancer cells and that it has potential use as a novel anti-cancer drug for bladder cancer.

Orostachys japonicus exerts antipancreatic cancer activity through induction of apoptosis and cell cycle arrest in PANC-1 cells

Targeted therapy at the molecular level is important for pancreatic cancer treatment. This study looked over the anticancer activity of Orostachys japonicus in a human pancreatic cancer cell line, PANC-1. An ethyl acetate fraction containing quercetin, kaempferol, and flavonol glycosides from O. japonicus (OJE) exhibited significant anticancer activity against the PANC-1. OJE activated caspase-3, caspase-8, and caspase-9, leading to the induction of both intrinsic and extrinsic apoptosis pathways. It also inhibited cyclin D1, cyclin B1, and cyclin-dependent kinase 4, representing cell cycle arrest at both G1/S and G2/M phases. In addition, OJE phosphorylated MAPKs such as p38, JNK, and ERK, which are important upstream signaling factors in apoptosis and arrest of cell cycle inducing system. In conclusion, OJE effectively exerted antipancreatic cancer activity via induction of apoptosis directed by both intrinsic and extrinsic pathways and arrest of cell cycle regulated at both G1/S and G2/M stages, which is activated by MAPKs, p38, JNK, and ERK.

Runt-related transcription factor 1 contributes to lung cancer development by binding to tartrate-resistant acid phosphatase 5

Lung cancer (LC) is one of the malignant tumors with growing morbidity and mortality. The involvement of runt-related transcription factor 1 (RUNX1) in LC patients has been elucidated. We intended to research mechanisms of RUNX1 and tartrate-resistant acid phosphatase 5 (ACP5) in LC. Firstly, ACP5 levels in LC tissues, paracancerous tissues, LC cells and tracheal epithelial cells were detected. RUNX1 overexpression plasmid and interference plasmid were constructed and transfected into 95C cells and A549 cells, respectively. The binding of RUNX1 to ACP5 promoter was tested. Additionally, the gain- and loss-of-function were performed to explore the effects of ACP5 and RUNX1 on LC biological process. The xenograft tumor in nude mice was constructed in vivo to verify in vitro results. Functional rescue experiment was performed by adding MAPK-specific activator P79350 to A549 cells with si-ACP5 to measure the effects of ERK/MAPK axis on LC progression. Consequently, we found ACP5 expression was higher in LC tissues and cells, and ACP5 silencing suppressed LC cell growth. Overexpression of ACP5 promoted malignant biological behavior of LC cells. RUNX1 could bind to ACP5 promoter, and overexpressed RUNX1 promoted ACP5 expression and LC cell growth. Moreover, ACP5 upregulated the ERK/MAPK axis and thus promoted LC progression. The results of xenograft tumor in nude mice showed that silencing ACP5 could inhibit the growth of LC cells in vivo. To conclude, silenced RUNX1 inhibits LC progression through the ERK/MAPK axis by binding to ACP5. This study may provide new approaches for LC treatment.

miR-454-3p promotes proliferation and induces apoptosis in human cervical cancer cells by targeting TRIM3

Abnormally expressed microRNAs have been demonstrated related to the development and progression of cervical cancer. However, the molecular mechanisms remain largely unkown. Here, we aimed to demonstrate the exact role of miR-454-3p in cervical cancer. Depletion of miR-454-3p in cervical cancer cells resulted in inhibition of cell growth and promotion of cell apoptosis. Bioinformatics analysis predicted that tripartite motif-containing 3 (TRIM3), a tumor suppressor gene in cervical cancer, is a promising target of miR-454-3p. Dual-luciferase reporter gene assay revealed that miR-454-3p directly target TIRM3 by binding to the 3'UTR of TIRM3. In cervical cancer cells (C-33A and SiHa) with endogenous low TRIM3 expression, decreased expression of miR-454-3p significantly elevated TRIM3 expression. In the cervical cancer cell (HeLa) with endogenous high TRIM3 expression, increased expression of miR-454-3p obviously inhibited TRIM3 expression and then manipulating cell growth and apoptosis, down-regulating the expression of P53 and cleaved caspase-3 via P38 MAPK signaling. Taken together, these findings demonstrated miR-454-3p as a cancer promoter by targeting TRIM3 in human cervical cancer.

Rotundic Acid Induces DNA Damage and Cell Death in Hepatocellular Carcinoma Through AKT/mTOR and MAPK Pathways

Hepatocellular carcinoma (HCC) is the fourth largest cause of cancer-related deaths worldwide with limited therapeutic interventions. Renewed interest in natural products as drug leads has resulted in a paradigm shift toward the rapid screening of medicinal plants for the discovery of new chemical entities. Rotundic acid (RA), a plant-derived triterpenoid, has been anecdotally reported to possess anti-inflammatory and cardio-protective abilities. The present study highlights the anti-cancer efficacy of RA on HCC in vitro and in vivo. The inhibitory effects of RA on HCC cell viability was determined by MTT. Soft agar colony formation and clonogenic assays also showed that RA inhibited HCC cell proliferation. Flow cytometry, confocal, and western blot results further indicated that RA induced cell cycle arrest, DNA damage, and apoptosis by modulating the AKT/mTOR and MAPK pathways. Besides the suppression of migration and invasion, tube formation and VEGF-ELISA revealed the anti-angiogenic abilities of RA on HCC. Moreover, RA also inhibited tumor growth in a HepG2 xenograft mouse model. To our best knowledge, this is the first extensive study of the anticancer activity of RA on HCC. The results demonstrate that RA could be a potential drug candidate for HCC treatment.

Genomewide identification and analysis of heat-shock proteins 70/110 to reveal their potential functions in Chinese soft-shelled turtle Pelodiscus sinensis

Heat-shock proteins 70/110 (Hsp70/110) are vital molecular chaperones and stress proteins whose expression and production are generally induced by extreme temperatures or external stresses. The Hsp70/110 family is largely conserved in diverse animals. Although many reports have studied and elaborated on the characteristics of Hsp70/110 in various species, the systematic identification and analysis of Hsp70/110 are still poor in turtles. In this study, a genomewide search was performed, and 18 candidate PsHSP70/110 family genes were identified in Chinese soft-shelled turtle, Pelodiscus sinensis. These PsHSP70/110 proteins contained the conserved "heat shock protein 70" domain. Phylogenetic analysis of PsHSP70/110 and their homologs revealed evolutionary conservation of Hsp70/110 across different species. Tissue-specific expression analysis showed that these PsHSP70/110 genes were differentially expressed in different tissues of P. sinensis. Furthermore, to examine the putative biological functions of PsHSP70/110, the dynamic expression of PsHSP70/110 genes was analyzed in the testis of P. sinensis during seasonal spermatogenesis following germ cell apoptosis. Notably, genes such as PsHSPA1B-L, PsHSPA2, and PsHSPA8 were significantly upregulated in P. sinensis testes along with a seasonal decrease in apoptosis. Protein interaction prediction revealed that PsHSPA1B-L, PsHSPA2, and PsHSPA8 may interact with each other and participate in the MAPK signaling pathway. Moreover, immunohistochemical analysis showed that PsHSPA1B-L, PsHSPA2, and PsHSPA8 protein expression was associated with seasonal temperature variation. The expression profiling and interaction relationships of the PsHSPA1B-L, PsHSPA2, and PsHSPA8 proteins implied their potential roles in inhibiting the apoptosis of germ cells in P. sinensis. These results provide insights into PsHSP70/110 functions and will serve as a rich resource for further investigation of HSP70/110 family genes in P. sinensis and other turtles.

A Novel Peptide from Abalone (Haliotis discus hannai) to Suppress Metastasis and Vasculogenic Mimicry of Tumor Cells and Enhance Anti-Tumor Effect In Vitro

Vasculogenic mimicry (VM) formed by tumor cells plays a vital role in the progress of tumor, because it provides nutrition for tumor cells and takes away the metabolites. Therefore, the inhibition of VM is crucial to the clinical treatment of tumors. In this study, we investigated the anti-tumor effect of a novel peptide, KVEPQDPSEW (AATP), isolated from abalone (Haliotis discus hannai) on HT1080 cells by migration, invasion analysis and the mode of action. The results showed that AATP effectively inhibited MMPs by blocking MAPKs and NF-κB pathways, leading to the downregulation of metastasis of tumor cells. Moreover, AATP significantly inhibited VM and pro-angiogenic factors, including VEGF and MMPs by suppression of AKT/mTOR signaling. In addition, molecular docking was used to study the interaction of AATP and HIF-1α, and the results showed that AATP was combined with an active site of HIF-1α by a hydrogen bond. The effect of AATP on anti-metastatic and anti-vascular in HT1080 cells revealed that AATP may be a potential lead compound for treatment of tumors in the future.

An Integrated Framework for Identifying Mutated Driver Pathway and Cancer Progression

Next-generation sequencing (NGS) technologies provide amount of somatic mutation data in a large number of patients. The identification of mutated driver pathway and cancer progression from these data is a challenging task because of the heterogeneity of interpatient. In addition, cancer progression at the pathway level has been proved to be more reasonable than at the gene level. In this paper, we introduce an integrated framework to identify mutated driver pathways and cancer progression (iMDPCP) at the pathway level from somatic mutation data. First, we use uncertainty coefficient to quantify mutual exclusivity on gene driver pathways and develop a computational framework to identify mutated driver pathways based on the adaptive discrete differential evolution algorithm. Then, we construct cancer progression model for driver pathways based on the Bayesian Network. Finally, we evaluate the performance of iMDPCP on real cancer somatic mutation datasets. The experimental results indicate that iMDPCP is more accurate than state-of-the-art methods according to the enrichment of KEGG pathways, and it also provides new insights on identifying cancer progression at the pathway level.

Downregulation of EIF5A2 by miR-221-3p inhibits cell proliferation, promotes cell cycle arrest and apoptosis in medulloblastoma cells

Recently, miR-221-3p expression has been reported to be down-regulated in medulloblastoma (MB), but its functional effects remains unclear. In this study, quantitative real-time PCR (qRT-PCR) revealed significantly decreased miR-221-3p in MB cell lines. Transfection of miR-221-3p mimics reduced, or inhibitor increased cell proliferation in MB cells using MTT assay. Flow cytometry analysis indicated miR-221-3p overexpression promoted, while knockdown alleviated G0/G1 arrest and apoptosis. Luciferase reporter assay confirmed miR-221-3p directly targets the EIF5A2 gene. Moreover, restoration of EIF5A2 in the miR-221-3p-overexpressing DAOY cells significantly alleviated the suppressive effects of miR-221-3p on cell proliferation, cell cycle and apoptosis. Furthermore, miR-221-3p overexpression decreased CDK4, Cyclin D1 and Bcl-2 and increased Bad expression, which was reversed by EIF5A2 overexpression. These results uncovered the tumor suppressive role of miR-221-3p in MB cell proliferation at least in part via targeting EIF5A2, suggesting that miR-221-3p might be a potential candidate target for diagnosis and therapeutics of MB.

1-(5-Bromo-2-hydroxy-4-methoxyphenyl)ethanone [SE1] Inhibits MMP-9 Expression by Regulating NF-κB and MAPKs Signaling Pathways in HT1080 Human Fibrosarcoma Cells

Hippocampus is a traditional medicine in China, which can be used for treating tumors, aging, fatigue, thrombosis, inflammation, hypertension, prostatic hyperplasia, and other diseases. 1-(5-Bromo-2-hydroxy-4-methoxyphenyl)ethanone [SE1] from seahorse (Hippocampus kuda Bleeler) has been shown to suppress proinflammatory responses. In the present study, SE1 potently inhibited gelatin digestion by MMP-9 induced by phorbol 12-myristate 13-acetate (PMA) and migration of human fibrosarcoma HT1080 cells in dose-dependent manner. Moreover, western blot analysis and immunofluorescence analysis have been studied on MAPKs (ERK1/2, p38 kinase and JNK) and NF-κB (p65 and IκB), which refer to the clear molecular mechanism. The results indicated that SE1 significantly suppressed the phosphorylation of mitogen-activated protein kinases (MAPK: p38 kinase and JNK) and NF-κB. Finally, molecular docking result showed SE1 interacts with TYR245 and HIS226 of MMP-9 by hydrogen bond and Pi-Pi bond to suppress MMP-9 activity. This data suggested that the SE1 may possess therapeutic and preventive potential for the treatment of MMP-9 related disorders.

Recent Advances in Herbal Medicines for Digestive System Malignancies

Herbal medicines, as an important part of traditional Chinese medicine (TCM), have been used to treat digestive system malignancies (DSM) for many years, and have gradually gained recognition worldwide. The role of herbal medicines in the comprehensive treatment of DSM is being improved from adjuvant treatment of the autologous immune function in cancer patients, to the treatment of both the symptoms and disease, direct inhibition of tumor cell growth and proliferation, and induction of tumor cell autophagy and apoptosis. Their specific mechanisms in these treatments are also being explored. The paper reviews the current anti-tumor mechanisms of TCM, including single herbal medicines, Chinese herbal formulations, Chinese medicine preparations and TCM extract, and their application in the comprehensive treatment of digestive system tumors, providing a reference for clinical application of TCM.

Cooking oil fume-derived PM2.5 induces apoptosis in A549 cells and MAPK/NF-кB/STAT1 pathway activation

Cooking oil fumes (COFs) are the major sources of indoor air pollution in Asia. It is well known that alveolar cells are key participants in the development of respiratory system; however, it still remains unknown whether alveolar cells are affected by COFs. Therefore, the present study investigated the effects of COFs on alveolar cells (A549 cells) and illuminated its apoptotic mechanism in response to COF-PM_2.5 exposure. When A549 cells were exposed to COF-PM_2.5, cell viability was substantially decreased, while the generation of ROS increased, and LDH levels and CCK-8 levels gradually changed within a dose-dependent manner. The nitrite concentration in the supernatants was augmented, while the SOD activity and GSH recycling were decreased upon COF-PM_2.5. Moreover, COF-PM_2.5 treatment increased mRNA levels of COX-2, inducible NO synthase, and TNF-α, and Elisa assay suggested that secretory proteins IL-6 and TNF-α were also increased. Furthermore, the Bax/Bcl-2 mRNA ratio was increased, and cleaved caspase-3 protein was activated in the A549 cells. Strikingly, COF-PM_2.5 induced the phosphorylation of STAT1 at Tyr701/Ser727 and activation of NF-кB and ERK1/2, p38, and JNK of the MAPK pathway. In short, our study suggested that COF-PM_2.5 resulted in inflammation, apoptosis, and cell damage in A549 cells, which might be modulated via the activation of MAPK/NF-кB/STAT1 pathway.

EIF5A1 promotes epithelial ovarian cancer proliferation and progression

Epithelial ovarian cancer (EOC) is one of the most common gynecological cancers and has the highest mortality rate thereof. We found abundant eukaryotic translation initiation factor 5A1 (EIF5A1) in 54 EOC tissues, and high EIF5A1 levels predicted poor survival. EIF5A1 ectopic expression enhanced EOC cell proliferative, migration, and invasive capabilities, while EIF5A1 knockdown suppressed them. Most importantly, GC7 (N1-guanyl-1,7-diaminoheptane, an EIF5A1 hypusination inhibitor) could reverse the effect of EIF5A1 upregulation on EOC cell proliferation, migration, and invasion and mutant type EIF5A1K50A plasmid [bearing a single point mutation (K50 → A50) that prevents hypusination] had no effects on these malignant behaviors. Our findings imply that EIF5A1 is a vital regulator of EOC proliferation and progression and is a potential prognostic marker and therapeutic target in EOC.

Activation of autophagy by stress-activated signals as a cellular self-defense mechanism against the cytotoxic effects of MBIC in human breast cancer cells in vitro

We recently reported that methyl 2-(-5-fluoro-2-hydroxyphenyl)-1H-benzo[d]imidazole-5-carboxylate (MBIC) is a microtubule targeting agent (MTA) with multiple mechanisms of action including apoptosis in two human breast cancer cell-lines MCF-7 and MDA-MB-231. In the present study, investigation of early molecular events following MBIC treatment demonstrated the induction of autophagy. This early (<24 h) response to MBIC was characterized by accumulation of autophagy markers; LC3-II, Beclin1, autophagic proteins (ATGs) and collection of autophagosomes but with different variations in the two cell-lines. MBIC-induced autophagy was associated with generation of reactive oxygen species (ROS). In parallel, an increased activation of SAPK/JNK pathway was detected, as an intersection of ROS production and induction of autophagy. The cytotoxic effect of MBIC was enhanced by inhibition of autophagy through blockage of SAPK/JNK signaling, suggesting that MBIC-induced autophagy, is a possible cellular self-defense mechanism against toxicity of this agent in both breast cancer cell-lines. The present findings suggest that inhibition of autophagy eliminates the cytoprotective activity of MDA-MB-231 and MCF-7 cells, and sensitizes both the aggressive and non-aggressive human breast cancer cell-lines to the cytotoxic effects of MBIC.

Artocarpin, an isoprenyl flavonoid, induces p53-dependent or independent apoptosis via ROS-mediated MAPKs and Akt activation in non-small cell lung cancer cells

Artocarpin has been shown to exhibit cytotoxic effects on different cancer cells, including non-small cell lung carcinoma (NSCLC, A549). However, the underlying mechanisms remain unclear. Here, we explore both p53-dependent and independent apoptosis pathways in artocarpin-treated NSCLC cells. Our results showed that artocarpin rapidly induced activation of cellular protein kinases including Erk1/2, p38 and AktS473. Inhibition of these protein kinases prevented artocarpin-induced cell death. Moreover, artocarpin-induced phosphorylation of these protein kinases and apoptosis were mediated by induction of reactive oxygen species (ROS), as pretreatment with NAC (a ROS scavenger) and Apocynin (a Nox-2 inhibitor) blocked these events. Similarly, transient transfection of p47Phox or p91Phox siRNA attenuated artocarpin-induced NADPH oxidase activity and cell death. In addition, p53 dependent apoptotic proteins including PUMA, cytochrome c, Apaf-1 and caspase 3 were activated by artocarpin, and these effects can be abolished by antioxidants, MAPK inhibitors (U0126 and SB202190), but not by PI3K inhibitor (LY294002). Furthermore, we found that artocarpin-induced Akt phosphorylation led to increased NF-κB activity, which may act as an upstream regulator in the c-Myc and Noxa pathway. Therefore, we propose that enhancement of both ERK/ p38/ p53-dependent or independent AktS473/NF-κB/c-Myc/Noxa cascade by Nox-derived ROS generation plays an important role in artocarpin-induced apoptosis in NSCLC cells.

DEPTOR promotes survival of cervical squamous cell carcinoma cells and its silencing induces apoptosis through downregulating PI3K/AKT and by up-regulating p38 MAP kinase

DEPTOR is an endogenous inhibitor of mTOR complexes, de-regulated in cancers. The present study reveals a vital role for DEPTOR in survival of cervical squamous cell carcinoma (SCC). DEPTOR was found to be overexpressed in both cervical SCC cells and tissues and it's silencing in cervical SCC cells induced apoptosis, mainly by up-regulation of p38 MAPK and by inhibiting PI3K/AKT pathway via a feed-back inhibition from mTORC1-S6K. DEPTOR silencing resulted in reduced expression of the nitric oxide synthases iNOS and eNOS, as well as increased activation of ERK1/2 and p38 MAP kinases. Activation of AKT signaling by overexpression of constitutively active-AKT (CA-AKT) failed to overcome the apoptosis caused by DEPTOR silencing. Similarly pharmacological inhibition of ERK also failed to control apoptosis. However pharmacological inhibition of p38 MAPK rescued the cells from apoptosis, indicating the major role of p38 MAPK in cell death induced by DEPTOR silencing. DEPTOR was also found to regulate ERK1/2 in an AKT dependent manner. DEPTOR knockdown induced cell death in SiHa cells overexpressing the anti-apoptotic Bcl-2 and Bcl-xL, indicating strong survival role of DEPTOR in these cells. DEPTOR overexpression activated PI3K/AKT by relieving the negative feed-back inhibition from mTORC1-S6K. DEPTOR regulation was also observed to be independent of HPV E6/E7 oncoproteins, but it might be a molecular co-factor contributing to cervical carcinogenesis. In summary, DEPTOR is found to promote survival of cervical SCC cells and its reduction induced apoptosis via differential effects on PI3K/AKT and p38 MAPK and can be a potential target in cervical SCC.