ANP32A Knockdown Attenuates the Malignant Biological Behavior of Colorectal Cancer Cells by Suppressing Epithelial-mesenchymal Transition and ERK Activation.

Acidic leucine rich nuclear phosphoprotein-32A (ANP32A) protein has a variety of functions, such as regulating cell differentiation, influencing cell apoptosis and cell cycle progression. Our previous study demonstrated that high expression of ANP32A was found in the tumor tissues of colorectal cancer (CRC) patients and was positively associated with tumor grading. However, the function and underlying mechanisms of ANP32A in CRC metastasis have not been fully explored. In this study, we found that ANP32A knockdown significantly attenuated the migration and invasion, and epithelial-mesenchymal transition (EMT) in cells. Further mechanistic studies revealed that ANP32A knockdown inhibited the expression of ß-catenin and phosphorylated-ERK. The immunofluorescent staining experiment has revealed that ANP32A was expressed in the cell membrane, cytosol and nucleus, and its expression was positively associated with ß-catenin expression levels. Moreover, the ability of cell migration and invasion was inhibited, the expression of E-cadherin was enhanced following ANP32A knockdown, and these affects were abolished by an ERK activator PMA, enhanced by an ERK inhibitor PD98059. Moreover, our animal experiment also demonstrated that silenced ANP32A inhibited CRC cell growth, multi-organ metastasis, ERK activation and EMT progression in vivo. Collectively, these findings demonstrated that ANP32A promotes CRC progression and that may be a promising target for the anti-metastasis treatment of CRC.

Metabolism and pharmacokinetic study of deuterated osimertinib.

Osimertinib is a highly selective third-generation irreversible inhibitor of epidermal growth factor receptor mutant, which can be utilized to treat non-small cell lung cancer. As the substrate of cytochrome P450 enzyme, it is mainly metabolized by the CYP3A enzyme in humans. Among the metabolites produced by osimertinib, AZ5104, and AZ7550, which are demethylated that is most vital. Nowadays, deuteration is a new design approach for several drugs. This popular strategy is deemed to improve the pharmacokinetic characteristics of the original drugs. Therefore, in this study the metabolism profiles of osimertinib and its deuterated compound (osimertinib-d3) in liver microsomes and human recombinant cytochrome P450 isoenzymes and the pharmacokinetics in rats and humans were compared. After deuteration, its kinetic isotope effect greatly inhibited the metabolic pathway that produces AZ5104. The plasma concentration of the key metabolite AZ5104 of osimertinib-d3 in rats and humans decreased significantly compared with that of the osimertinib. This phenomenon was consistent with the results of the metabolism studies in vitro. In addition, the in vivo results indicated that osimertinib-d3 had higher systemic exposure (AUC) and peak concentration (Cmax ) compared with the osimertinib in rats and human body.

Curcumol simultaneously induces both apoptosis and autophagy in human nasopharyngeal carcinoma cells.

Autophagy is usually considered as a protective mechanism against cell death, and in the meantime, leads to cell injury even apoptosis. Apoptosis and autophagy are very closely connected and may cooperate, coexist, or antagonize each other on progressive occurrence of cell death triggered by natural compounds. Therefore, the interplay between the two modes of death is essential for the overall fate of cancer cells. Our previous study revealed that curcumol induced apoptosis in nasopharyngeal carcinoma (NPC) cells. Recently, curcumol was found to induce autophagy in cancer cells. However, whether curcumol can induce NPC cells autophagy and the effects of autophagy on apoptosis remain elusive. In this study, we found that curcumol induced autophagy through AMPK/mTOR pathway in CNE-2 cells. Moreover, inhibiting autophagy by autophagy inhibitor 3-methyladenine (3-MA) or apoptosis inhibitor z-VAD-fmk significantly increased proliferation while attenuated apoptosis and autophagy compared with the curcumol 212 µM group. In contrast, combining curcumol with autophagy agonist rapamycin and apoptosis inducer MG132 synergized the apoptotic and autophagic effect of curcumol. Taken together, our study demonstrates that curcumol promotes autophagy in NPC via AMPK/mTOR pathway, induces autophagy enhances the activity of curcumol in NPC cells; the combination of autophagy inducer and curcumol can be a new therapeutic strategy for NPC.

Curcumol inhibits EBV-positive Nasopharyngeal carcinoma migration and invasion by targeting nucleolin.

Metastasis is a major cause of recurrence and death in patients with EBV-positive Nasopharyngeal carcinoma (NPC). Previous reports documented that curcumol has both anti-cancer and anti-viral effects, but there is little literature systematically addressing the mechanism of curcumol in EBV-positive tumors. Previously we found that nucelolin (NCL) is a target protein of curcumol in CNE2 cells, an EBV-negative NPC, and in this experiment, we reported a critical role for NCL in promoting migration and invasion of C666-1 cells, an EBV-positive NPC, and found that the expression of NCL determined the level of curcumol's efficacy. Mechanistically, NCL interacted with Epstein-Barr Virus Nuclear Antigen 1 (EBNA1) to activate VEGFA/VEGFR1/PI3K/AKT signaling pathway, which in turn promoted NPC cell invasion and metastasis. Moreover, further study showed that the differential expression of NCL and curcumol intervention only had a regulatory effect on the nuclear accumulation of VEGFR1, which strengthened the anti-cancer effect of curcumol mediated through NCL. Our findings indicated that curcumol exerted anti EBV-positive NPC invasion and metastasis by downregulating EBNA1 and inhibiting VEGFA/VEGFR1/PI3K/AKT signaling by targeting NCL, which provides a novel pharmacological basis for curcumol's clinical use in treating patients with EBV-positive NPC.

Curcumol inhibits the viability and invasion of colorectal cancer cells via miR-30a-5p and Hippo signaling pathway.

MicroRNA-30a-5p (miR-30a-5p), which functions as a tumor suppressor, has been reported to be downregulated in colorectal cancer (CRC) tissues and to be associated with cancer invasion. However, the detailed regulatory mechanism of curcumol in the malignant progression of CRC remains unknown. MTT, Transwell, scratch, western blotting and reverse transcription-quantitative PCR assays were performed to examine how curcumol inhibited CRC cell viability, invasion and migration, and to detect the role of miR-30a-5p and curcumol in the invasion and Hippo signaling pathways of CRC cells. The present study revealed that miR-30a-5p expression was downregulated in human CRC tissues and cells. The results demonstrated that miR-30a-5p downregulation was accompanied by the inactivation of the Hippo signaling pathway, which was demonstrated to promote CRC cell viability, invasion and migration. Curcumol treatment was identified to increase miR-30a-5p expression and to activate the Hippo signaling pathway, which in turn inhibited the invasion and migration of CRC cells. Overexpression of miR-30a-5p enhanced the effects of curcumol on cell invasion and migration, and the Hippo signaling pathway in CRC cells. Furthermore, downregulation of miR-30a-5p reversed the effects of curcumol on cell invasion and migration, and the Hippo signaling pathway in CRC cells. These findings identified novel signaling pathways associated with miR-30a-5p and revealed the effects of curcumol on miR-30a-5p expression. Therefore, curcumol may serve as a potential therapeutic strategy to delay CRC progression.

Osthole induces necroptosis via ROS overproduction in glioma cells.

Glioma is a common primary malignant tumor that has a poor prognosis and often develops drug resistance. The coumarin derivative osthole has previously been reported to induce cancer cell apoptosis. Recently, we found that it could also trigger glioma cell necroptosis, a type of cell death that is usually accompanied with reactive oxygen species (ROS) production. However, the relationship between ROS production and necroptosis induced by osthole has not been fully elucidated. In this study, we found that osthole could induce necroptosis of glioma cell lines U87 and C6; such cell death was distinct from apoptosis induced by MG-132. Expression of necroptosis inhibitor caspase-8 was decreased, and levels of necroptosis proteins receptor-interacting protein 1 (RIP1), RIP3 and mixed lineage kinase domain-like protein were increased in U87 and C6 cells after treatment with osthole, whereas levels of apoptosis-related proteins caspase-3, caspase-7, and caspase-9 were not increased. Lactate dehydrogenase release and flow cytometry assays confirmed that cell death induced by osthole was primarily necrosis. In addition, necroptosis induced by osthole was accompanied by excessive production of ROS, as observed for other necroptosis-inducing reagents. Pretreatment with the RIP1 inhibitor necrostatin-1 attenuated both osthole-induced necroptosis and the production of ROS in U87 cells. Furthermore, the ROS inhibitor N-acetylcysteine decreased osthole-induced necroptosis and growth inhibition. Overall, these findings suggest that osthole induces necroptosis of glioma cells via ROS production and thus may have potential for development into a therapeutic drug for glioma therapy.

PTEN/AKT/mTOR signaling mediates anticancer effects of epigallocatechin­3­gallate in ovarian cancer.

Epigallocatechin­3­gallate (EGCG), a polyphenol present in green tea, exhibits anticancer effects in various types of cancer. A number of studies have focused on the effects of EGCG on lung cancer, but not ovarian cancer. Previous reports have implicated that EGCG suppressed ovarian cancer cell proliferation and induced apoptosis, but its potential anticancer mechanisms and signaling pathways remain unclear. Thus, it is necessary to determine the anti­ovarian cancer effects of EGCG and explore the underlying mechanisms. In the present study, EGCG exerted stronger proliferation inhibition on SKOV3 cells compared with A549 cells and induced apoptosis in SKOV3 cells, as well as upregulated PTEN expression and downregulated the expression of phosphoinositide­dependent kinase­1 (PDK1), phosphor (p)­AKT and p­mTOR. These effects were reversed by the PTEN inhibitor VO­Ohpic trihydrate. The results of the mouse xenograft experiment demonstrated that 50 mg/kg EGCG exhibited increased tumor growth inhibition compared with 5 mg/kg paclitaxel. In addition, PTEN expression was upregulated, whereas the expression levels of PDK1, p­AKT and p­mTOR were downregulated in the EGCG treatment group compared with those in untreated mice in vivo. In conclusion, the results of the present study provided a new underlying mechanism of the effect of EGCG on ovarian cancer and may lead to the development of EGCG as a candidate drug for ovarian cancer therapy.

Curcumol inhibits colorectal cancer proliferation by targeting miR-21 and modulated PTEN/PI3K/Akt pathways.

AIMS: The purpose of this study was to demonstrate how curcumol affected the expression of miR-21 and whether its effects on miR-21 was associated with the activation of PTEN/PI3K/Akt pathways in CRC cells. MAIN METHODS: MTT and xenograft assay were used to examine how curcumol inhibits colorectal cancer (CRC) cells' growth. Q-PCR and western blot analysis were employed to test the role of miR-21 in the inhibition of curcumol on proliferation and PTEN/PI3K/Akt pathways of CRC cells. KEY FINDINGS: We found that curcumol effectively inhibited CRC cells from proliferating via the PTEN/PI3K/Akt pathways and reduced expression of miR-21 both in vitro and in vivo. miR-21 mimics were found to decrease the protein level of PTEN and increase the expression of PI3K, phospho-Akt (p-Akt) and NF-κB, while miR-21 sponge (miR-21-SP) enhanced the expression of PTEN and reduced the activity of PI3K, Akt and NF-κB. Furthermore, miR-21-SP strengthened the role of curcumol in up-regulating PTEN and inhibiting PI3K/Akt pathways, but miR-21 reversed the effect of curcumol on the PTEN/PI3K/Akt pathways. SIGNIFICANCE: Our research demonstrated that curcumol reduced the proliferation of CRC cells through PTEN/PI3K/Akt by targeting miR-21 and miR-21 could be a target molecule of curcumol for CRC treatment.

Curcumol induces cell cycle arrest and apoptosis by inhibiting IGF-1R/PI3K/Akt signaling pathway in human nasopharyngeal carcinoma CNE-2 cells.

Curcumol has been proved to possess antitumor effects in vivo and in vitro in several cancers. Previously, we have found that curcumol induced apoptosis in CNE-2 cells, but its underlying mechanism has not yet been studied well. Recently, our team clarified that curcumol inhibited colorectal cancer cells' growth partially through insulin-like growth factor 1 receptor (IGF-1R) pathway. Given the key importance of IGF-1R pathway in tumorigenesis, we want to explore whether curcumol effects on nasopharyngeal carcinoma (NPC) cells relates to IGF-1R and its downstream pathway inactivation. In this study, we found that curcumol inhibited IGF-1R and p-Akt expression in a dose- and time-dependent way. In addition, it also regulated their downstream GSK-3ß's activity in CNE-2 cells, which further triggering alterations in the expression of cycle- and apoptosis-related molecules, and then leading to G0/G1-phase arrest and apoptosis. Moreover, curcumol's effect on CNE-2 cells was partly eliminated by IGF-1R's agonist IGF-1. In conclusion, our findings indicated that the inhibitory effect of curcumol on proliferation of NPC cells is related to the inhibition of IGF-1R and its downstream PI3K/Akt/GSK-3ß pathway.

Identification and validation nucleolin as a target of curcumol in nasopharyngeal carcinoma cells.

Identification of the specific protein target(s) of a drug is a critical step in unraveling its mechanisms of action (MOA) in many natural products. Curcumol, isolated from well known Chinese medicinal plant Curcuma zedoary, has been shown to possess multiple biological activities. It can inhibit nasopharyngeal carcinoma (NPC) proliferation and induce apoptosis, but its target protein(s) in NPC cells remains unclear. In this study, we employed a mass spectrometry-based chemical proteomics approach reveal the possible protein targets of curcumol in NPC cells. Cellular thermal shift assay (CETSA), molecular docking and cell-based assay was used to validate the binding interactions. Chemical proteomics capturing uncovered that NCL is a target of curcumol in NPC cells, Molecular docking showed that curcumol bound to NCL with an -7.8 kcal/mol binding free energy. Cell function analysis found that curcumol's treatment leads to a degradation of NCL in NPC cells, and it showed slight effects on NP69 cells. In conclusion, our results providing evidences that NCL is a target protein of curcumol. We revealed that the anti-cancer effects of curcumol in NPC cells are mediated, at least in part, by NCL inhibition. SIGNIFICANCE: Many natural products showed high bioactivity, while their mechanisms of action (MOA) are very poor or completely missed. Understanding the MOA of natural drugs can thoroughly exploit their therapeutic potential and minimize their adverse side effects. Identification of the specific protein target(s) of a drug is a critical step in unraveling its MOA. Compound-centric chemical proteomics is a classic chemical proteomics approach which integrates chemical synthesis with cell biology and mass spectrometry (MS) to identify protein targets of natural products determine the drug mechanism of action, describe its toxicity, and figure out the possible cause of off-target. It is an affinity-based chemical proteomics method to identify small molecule-protein interactions through affinity chromatography approach coupled with mass spectrometry, has been conventionally used to identify target proteins and has yielded good results. Curcumol, has shown effective inhibition on Nasopharyngeal Carcinoma (NPC) Cells, interacted with NCL and then initiated the anti-tumor biological effect. This research demonstrated the effectiveness of chemical proteomics approaches in natural drugs molecular target identification, revealing and understanding of the novel mechanism of actions of curcumol is crucial for cancer prevention and treatment in nasopharynx cancer.

Curcumol induces cell cycle arrest in colon cancer cells via reactive oxygen species and Akt/ GSK3ß/cyclin D1 pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Curcuma kwangsiensis S. G. Lee & C. F. Liang (Guangxi ezhu, in Chinese) belongs to the Zingiberaceae family, has been used as a traditionally Chinese medicine nearly 2000 year. Curcumol is one of the guaiane-type sesquiterpenoid hemiketal isolated from medicine plant Curcuma kwangsiensis S. G. Lee & C. F. Liang, which has been reported possesses anti-cancer effects. Our previous study found that the most contribution to inhibit nasopharyngeal carcinoma cell growth was curcumol. AIM OF THE STUDY: To assess the effect of curcumol on cell cycle arrest against human colon cancer cells (CRC) cells (LoVo and SW480) and explore its mechanism in vitro and in vivo. MATERIALS AND METHODS: Curcumol was dissolved in absolute ethyl alcohol. The concentration of absolute ethyl alcohol in the control group or in experimental samples was always 1/500 (v/v) of the final medium volume. LoVo and SW480 cells were treated with different concentrations of curcumol (0, 53, 106, 212 and 424µM). And then the cell cycle of each group was examined by flow cytometry. The protein levels of PI3K, p-Akt, cyclin D1, cyclin E, CDK2, CDK4 and GSK3ß were determined by Western blot. The mRNA expression of PI3K, Akt, cyclin D1, CDK4, P27, p21, and P16 in the treated cells were analyzed by real-time RT-PCR. In addition, the antitumor activity of curcumol was evaluated in nude mice bearing orthotopic tumor implants. RESULTS: Curcumol induced cell cycle arrest in G1/S phase. RT-qPCR and Western blot data showed that curcumol enhanced the expression of GSK3ß, P27, p21 and P16, and decreased the levels of PI3K, phosphorylated Akt (p-Akt), cyclin D1, CDK4, cyclin E and CDK2. Furthermore, curcumol induced reactive oxygen species (ROS) generation in LoVo cells, and ROS scavenger N-acetylcysteine (NAC) significantly reversed curcumol-induced cell growth inhibition. Besides, curcumol also prevented the growth of human colon cancer cells xenografts in nude mouse, accompanied by the reduction of PI3K, Akt, cyclin D1, CDK4, cycln E and significant increase of GSK3ß. CONCLUSIONS: Curcumol caused cell cycle arrest at the G0/G1 phase by ROS production and Akt/ GSK3ß/cyclin D1 pathways inactivation, indicating the potential of curcumol in the prevention of colon cancer carcinogenesis.

ANP32A modulates cell growth by regulating p38 and Akt activity in colorectal cancer.

Acidic leucine-rich nuclear phosphoprotein-32A (ANP32A) possesses multiple biochemical activities, has been found to be decreased or absent in malignant tumors. However, new findings have shown that it is expressed in greater amounts in advanced cancers than in early-stage tumors. The role and clinical significance of ANP32A in colorectal cancer (CRC) is still unknown. In the present study, the expression of ANP32A was assessed in 68 CRC patients by IHC, and then the correlation of its expression with clinicopathological factors was investigated using the Allred, Klein and immune response scoring system analysis. Western blot and real-time PCR analyses were used to assess ANP32A expression and the activity of Akt and p38 in cancer and normal tissues. These data indicated a significant association between ANP32A expression and the activity of Akt and p38, besides the tumor differentiation status in CRC patients. IHC and western blotting data revealed that ANP32A was overexpressed in CRC patients, and ANP32A levels were higher in poorly differentiated tumors. Protein and mRNA analysis revealed that with a high expression of ANP32A, the activation of Akt was enhanced, while the p-38 phosphorylation level was decreased in CRC tissues. MTT assay and functional studies revealed that knockdown of ANP32A inhibited cell growth and induced p38 phosphorylation and Akt dephosphorylation. The present study indicated that ANP32A promoted CRC proliferation by inhibition of p38 and activation of Akt signaling pathways and suggested that ANP32A may play a potential role in CRC diagnosis and therapy.

Crystallization and preliminary X-ray analysis of the vWA domain of human anthrax toxin receptor 1.

The Gram-positive spore-forming bacterium Bacillus anthracis causes anthrax by secreting anthrax toxin, which consists of protective antigen (PA), lethal factor and oedema factor. Binding of PA to receptors triggers the multi-step process of anthrax toxin entry into target cells. Two distinct cellular receptors, ANTXR1 (also known as tumour endothelial marker 8; TEM8) and ANTXR2 (also known as capillary morphogenesis protein 2; CMG2), for anthrax toxin have been identified. Although the crystal structure of the extracellular von Willebrand factor A (vWA) domain of CMG2 has been reported, the difference between the vWA domains of TEM8 and CMG2 remains unclear because there are no structural data for the TEM8 vWA domain. In this report, the TEM8 vWA domain was expressed, purified and crystallized. X-ray diffraction data were collected to 1.8 Šresolution from a single crystal, which belonged to space group P1 with unit-cell parameters a=65.9, b=66.1, c=74.4 Å, α=63.7, ß=88.2, γ=59.9°.