Targeting CDK12 obviates the malignant phenotypes of colorectal cancer through the Wnt/ß-catenin signaling pathway.

Colorectal cancer (CRC) is the second most common cause of cancer-related mortality and lies third in terms of morbidity due to the limited number of effective druggable targets. Since cancer stem cells (CSCs) are considered to be one of the roots of tumorigenesis, outgrowth and metastasis, targeting CSCs may be a promising strategy to reverse the malignant phenotypes of CRC. Cyclin-dependent kinase 12 (CDK12) has been reported to be involved in the self-renewal of CSCs in various cancers, rendering it an attractive potential target against CSCs to consequently limit the malignant phenotypes in CRC. In the present study, we aimed to investigate whether CDK12 can be a potential therapeutic target for patients with CRC and clarify its underlying mechanism. We found that CDK12, but not CDK13 is required for CRC survival. CDK12 was found to drive tumor initiation according to the colitis-associated colorectal cancer mouse model. In addition, CDK12 promoted CRC outgrowth and hepatic metastasis in the subcutaneous allograft and liver metastasis mouse models, respectively. In particular, CDK12 was able to induce the self-renewal of CRC CSCs. Mechanistically, the activation of Wnt/ß-catenin signaling mediated by CDK12 was implicated in stemness regulation and malignant phenotype maintenance. These findings indicate that CDK12 is a candidate druggable target in CRC. Therefore, the CDK12 inhibitor SR-4835 warrants clinical trial testing in patients with CRC.

CDK12 orchestrates super-enhancer-associated CCDC137 transcription to direct hepatic metastasis in colorectal cancer.

BACKGROUND: Hepatic metastasis is the primary and direct cause of death in individuals with colorectal cancer (CRC) attribute to lack of effective therapeutic targets. The present study aimed to identify potential druggable candidate targets for patients with liver metastatic CRC. METHODS: The transcriptional profiles of super-enhancers (SEs) in primary and liver metastatic CRC were evaluated in publicly accessible CRC datasets. Immunohistochemistry of human CRC tissues was conducted to determine the expression level of CDK12. Cellular proliferation, survival and stemness were examined upon CDK12 inhibition by shCDK12 or a selective CDK12 inhibitor named SR-4835 with multiple in vitro and in vivo assays. RNA sequencing and bioinformatics analyses were carried out to investigate the mechanisms of CDK12 inhibition in CRC cells. RESULTS: We identified CDK12 as a driver gene for direct hepatic metastasis in CRC. Suppression of CDK12 led to robust inhibition of proliferation, survival and stemness. Mechanistically, CDK12 intervention preferentially repressed the transcription of SE-associated genes. Integration of the SE landscape and RNA sequencing, BCL2L1 and CCDC137 were identified as SE-associated oncogenic genes to strengthen the abilities of cellular survival, proliferation and stemness, eventually increasing liver metastasis of CRC. CONCLUSIONS: Our data highlight the potential of CDK12 and SE-associated oncogenic transcripts as therapeutic targets for patients with liver metastatic CRC.

Asiatic acid re-sensitizes multidrug-resistant A549/DDP cells to cisplatin by down regulating long non-coding RNA metastasis associated lung adenocarcinoma transcript 1/ß-catenin signaling.

Drug resistance becomes a challenge in the therapeutic management of non-small cell lung cancer (NSCLC). According to our former research, asiatic acid (AA) re-sensitized A549/DDP cells to cisplatin (DDP) through decreasing multidrug resistance protein 1 (MDR1) expression level. However, the relevant underlying mechanisms are still unclear. Long non-coding RNA (lncRNA) MALAT1 shows close association with chemo-resistance. As reported in this research, AA increased apoptosis rate, down regulated the expression of MALAT1, p300, ß-catenin, and MDR1, up regulated the expression of miR-1297, and decreased ß-catenin nuclear translocation in A549/DDP cells. MALAT1 knockdown expression abolished the drug resistance of A549/DDP cells and increased cell apoptosis. MALAT1 could potentially produce interactions with miR-1297, which targeted to degradation of p300. In addition, p300 overexpression effectively rescued the effects of MALAT1 knockdown expression on A549/DDP cells and activate the expression of ß-catenin/MDR1 signaling, and these could be effectively blocked by AA treatment. Conclusively, AA could re-sensitize A549/DDP cells to DDP through down-regulating MALAT1/miR-1297/p300/ß-catenin signaling.

Involvement of mTOR/Survivin signaling pathway in TUA(2ß, 3ß, 23-trihydroxy-urs-12-ene-28-olic acid)-induced apoptosis in human gastric cancer cell line BGC823 cells.

ETHNO-PHARMACOLOGICAL RELEVANCE: A natural ursolic compound, 2ß,3ß,23-trihydroxy-urs-12-ene-28-olic acid (TUA) was isolated from the root of Actinidiafulvicoma Hance. (A.fulvicoma Radix), which is used as a traditional hebal medicine to cure innominate inflammation of unknown origin of the digestive tract in the She nationality. AIM OF THE STUDY: The aim of present study was to investigate the effects of TUA on gastric cancer and to clarify the potential mechanisms in human gastric cancer cell line BGC823 cells in vitro and in vivo. MATERIALS AND METHODS: Cell proliferation, apoptosis, cell cycle, autophagy were all measured by MTS assay, flow cytometry following exposure to TUA. The mRNA expressions of PI3K, AKT, mTOR, P70S6K, Survivin and the protein expressions of p-PI3K, p-AKT, p-mTOR, p-P70S6K, Survivin were determined by qRT-PCR and Western blotting analysis, respectively. In vivo antitumor activity of TUA was assessed in a xenograft model. RESULTS: In vitro studies showed that TUA significantly suppressed the viability of BGC823 cells in a concentration- and time-dependent manner but not GES-1 non-tumorigenic human gastric epithelial cells. TUA also significantly increased the apoptosis rate and the sub G2 population by cell cycle analysis in a concentration dependent manner. Exposure to TUA decreased PI3K, AKT, mTOR, P70S6K, Survivin mRNA, inhibited the phosphorylation of major receptors involved in autophagy and apoptosis, such as PI3K, AKT, mTOR and P70S6K, while reduced the expression of Survivin in BGC cells. In vivo studies showed that TUA decreased tumor volume and tumor weight and also down regulated the autophagy-related proteins expression. CONCLUSIONS: TUA occupies underlying antitumor effects, the potential mechanisms may involve the suppression of mTOR/Survivin pathways connected to autophagy and the activation of apoptotic pathways in gastric cancer cells.

Unravel the molecular mechanism of XBP1 in regulating the biology of cancer cells.

Cancer cells are usually exposed to stressful environments, such as hypoxia, nutrient deprivation, and other metabolic dysfunctional regulation, leading to continuous endoplasmic reticulum (ER) stress. As the most conserved branch among the three un-folded protein response (UPR) pathways, Inositol-requiring enzyme 1α (IRE1α)-X-box-binding protein 1 (XBP1) signaling has been implicated in cancer development and progression. Active XBP1 with transactivation domain functions as a transcription factor to regulate the expression of downstream target genes, including many oncogenic factors. The regulatory activity of XBP1 in cell proliferation, apoptosis, metastasis, and drug resistance promotes cell survival, leading to tumorigenesis and tumor progression. In addition, the XBP1 peptides-based vaccination and/or combination with immune-modulatory drug administration have been developed for effective management for several cancers. Potentially, XBP1 is the biomarker of cancer development and progression and the strategy for clinical cancer management.

Extracellular vesicles in mesenchymal stromal cells: A novel therapeutic strategy for stroke.

A stroke is a focal cerebral insult that frequently causes severe neurological deficit and mortality. Recent studies have demonstrated that multipotent mesenchymal stromal cells (MSCs) hold great promise for neurovascular remodeling and neurological function recovery following a stroke. Rather than a direct replacement of parenchymal brain cells, the therapeutic mechanism of MSCs is suggested to be the secretion of soluble factors. Specifically, emerging data described MSCs as being able to release extracellular vesicles (EVs), which contain a variety of cargo including proteins, lipids, DNA and various RNA species. The released EVs can target neurocytes and vascular cells and modify the cell's functions by delivering the cargo, which are considered to mediate the neural restoration effects of MSCs. Therefore, EVs may be developed as a novel cell-free therapy for neurological disorders. In the present review, the current advances regarding the components, functions and therapeutic potential of EVs are summarized and the use of MSC-derived EVs as a promising approach in the treatment of stroke are highlighted.

Asiatic Acid (AA) Sensitizes Multidrug-Resistant Human Lung Adenocarcinoma A549/DDP Cells to Cisplatin (DDP) via Downregulation of P-Glycoprotein (MDR1) and Its Targets.

BACKGROUND/AIMS: P-glycoprotein (P-gp, i.e., MDR1) is associated with the phenotype of multidrug resistance (MDR) and causes chemotherapy failure in the management of cancers. Searching for effective MDR modulators and combining them with anticancer drugs is a promising strategy against MDR. Asiatic acid (AA), a natural triterpene isolated from the plant Centella asiatica, may have an antitumor activity. The present study assessed the reversing effect of AA on MDR and possible molecular mechanisms of AA action in MDR1-overexpressing cisplatin (DDP)-resistant lung cancer cells, A549/DDP. METHODS: Human lung adenocarcinoma A549/DDP cells were either exposed to different concentrations of AA or treated with DDP, and their viability was measured by the MTT assay. A Rhodamine 123 efflux assay, immunofluorescent staining, ATPase assay, reverse-transcription PCR (RT-PCR), and western blot analysis were conducted to elucidate the mechanisms of action of AA on MDR. RESULTS: Our results showed that AA significantly enhanced the cytotoxicity of DDP toward A549/DDP cells but not its parental A549 cells. Furthermore, AA strongly inhibited P-gp expression by blocking MDR1 gene transcription and increased the intracellular accumulation of the P-gp substrate Rhodamine 123 in A549/DDP cells. Nuclear factor (NF)-kB (p65) activity, IkB degradation, and NF-kB/p65 nuclear translocation were markedly inhibited by pretreatment with AA. Additionally, AA inhibited the MAPK-ERK pathway, as indicated by decreased phosphorylation of ERK1 and -2, AKT, p38, and JNK, thus resulting in reduced activity of the Y-box binding protein 1 (YB1) via blockage of its nuclear translocation. CONCLUSIONS: AA reversed P-gp-mediated MDR by inhibition of P-gp expression. This effect was likely related to downregulation of YB1, and this effect was mediated by the NF-kB and MAPK-ERK pathways. AA may be useful as an MDR reversal agent for combination therapy in clinical trials.

The Versatile Effects of Dihydromyricetin in Health.

Dihydromyricetin is a flavonoid isolated from Ampelopsis grossedentata, which is traditionally used in China. Dihydromyricetin exhibits health-benefiting activities with minimum adverse effects. Dihydromyricetin has been demonstrated to show antioxidative, anti-inflammatory, anticancer, antimicrobial, cell death-mediating, and lipid and glucose metabolism-regulatory activities. Dihydromyricetin may scavenge ROS to protect against oxidative stress or potentiate ROS generation to counteract cancer cells selectively without any effects on normal cells. However, the low bioavailability of dihydromyricetin limits its potential applications. Recent research has gained positive and promising data. This review will discuss the versatile effects and clinical prospective of dihydromyricetin.

Adiponectin Inhibits TNF-α-Activated PAI-1 Expression Via the cAMP-PKA-AMPK-NF-κB Axis in Human Umbilical Vein Endothelial Cells.

BACKGROUND: Tumor necrosis factor (TNF)-α can upregulate the expression of plasminogen activator inhibitor (PAI)-1, an inhibitor of fibrinolysis. Adiponectin (Adp) antagonizes TNF-α by negatively regulating its expression in various tissues. In the present study, the ability of Adp to suppress TNF-α-induced PAI-1 upregulation and the underlying mechanisms were evaluated. METHODS: Human umbilical vein endothelial cells (HUVECs) were treated with TNF-α in the presence or absence of Adp, and PAI-1 mRNA and antigen expression, activated signaling pathways, and molecular mechanisms were analyzed by qRT-PCR and ELISA. RESULTS: Adp decreased the TNF-α-induced upregulation of PAI-1 mRNA and protein expression and suppressed TNF-α-induced cAMP-PKA-AMPK inactivation. Adp also suppressed the TNF-α-induced NF-kB binding capability on the PAI-1 promoter. Moreover, these Adp-induced effects were further enhanced or prevented by treatment with the cAMP inhibitor Rp-cAMPs or activator forskolin, respectively. CONCLUSIONS: Our data suggest that Adp abrogates TNF-α-activated PAI-1 expression by activating cAMP-PKA-AMPK signaling to suppress NF-kB binding to the PAI-1 promoter in HUVECs. Given the antifibrotic effect of PAI-1 abrogation, Adp may be utilized as a novel agent in the treatment of fibrotic diseases.

CRA(Crosolic Acid) isolated from Actinidia valvata Dunn.Radix induces apoptosis of human gastric cancer cell line BGC823 in vitro via down-regulation of the NF-κB pathway.

A natural ursolic compound, 2α,3ß-dihydroxy-urs-12-en-28-oic acid (corosolic acid, CRA) was isolated from the root of Actinidia valvata Dunn. (A. valvata Radix). Since a large number of triterpenoid compound has marked anticancer effects toward various types of cancer cell lines in vitro, this study was carried out to investigate the anticancer effect of CRA in human gastric cancer cell line BGC823 cells and the underlying apoptotic mechanism of CRA was examined in BGC823 cell lines. The results showed that CRA significantly suppressed the viability of BGC823 cells in a concentration- and time-dependent manner. CRA also significantly increased the sub G1 population by cell cycle analysis in a concentration dependent manner. Exposure to CRA decreased p65, bcl-2, Fas, smac mRNA and protein expression, and increased IκBα, bax, survivin mRNA and protein expression. Results of immunofluorescence staining and EMSA further indicated CRA induced apoptosis by inhibiting nuclear translocation of nuclear factor NF-κB subunit p65. Consistently overall, our findings suggest that CRA induces apoptosis via inhibition of NF-κB (p65) expression level and activation of IκBα in BGC cells as a potent anticancer candidate for gastric cancer treatment.

2ß, 3ß, 23-trihydroxy-urs-12-ene-28-olic acid (TUA) isolated from Actinidia chinensis Radix inhibits NCI-H460 cell proliferation by decreasing NF-κB expression.

A natural ursolic compound, 2ß, 3ß, 23-trihydroxy-urs-12-ene-28-olic acid (TUA) was isolated from the root of Actinidia chinensis Planch (A. chinensis Radix). Since a large number of triterpenoid compound has marked anticancer effects toward various types of cancer cell lines in vitro, this study was carried out to investigate the anticancer effect of TUA in non-small cell lung cancer cells (NSCLCCs) and the underlying apoptotic mechanism of TUA was examined in NCI-H460 cell lines. Cell proliferation, apoptosis and cell cycle were measured using a cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. The activity of transcription factor NF-κB was determined by EMSA method. The expression of apoptosis- and proliferation-related proteins was determined by western blotting. The effect of TUA on NF-κB mRNA expression in NCI-H460 cells was detected by RT-PCR. TUA significantly suppressed the viability of NCI-H460 cells. Also, TUA significantly increased the sub G1 population by cell cycle analysis and in a concentration dependent manner in NCI-H460 cells. Such an effect was accompanied by p65 (NF-κB subunit) inactivation by an inhibition of IκBα phosphorylation, and by inhibition of p65 mRNA expressions. Consistently Overall, our findings suggest that TUA induces apoptosis via inhibition of NF-κB (p65) expression level and activation of IκBα in NCI-H460 cells as a potent anticancer candidate for lung cancer treatment.

Authentication of Polygonati Odorati Rhizoma and other two Chinese Materia Medica of the Liliaceae family by pharmacognosy technique with GC-MS analysis.

Yuzhu (Polygonati Odorati Rhizoma), Kangdingyuzhu (Polygonati Prattii Rhizoma), and zhugenqiyuzhu (Disporopsis Fuscopictae Rhizoma) are of the same family, but of different genera. They have all often used in Chinese Materia Medica (CMM) as Polygonati Odorati Rhizoma in China market. Three species of CMM are confused. For better application, we need to identify these plants accurately. This study use pharmacognosy technique and GC-MS analysis, three species of CMM were authenticated. In macroscopic characteristics, the fruit of Polygonati Odorati Rhizoma is blue-black, while the other two are maroon and dark purple orderly. Nodes of Polygonati Odorati Rhizoma are upward and light uplift, about 1 cm spacing, while the other are not. As for microscopic characteristics, the cortex of Polygonati Odorati Rhizoma only occupies about 1/5 of the radius of the transverse section with inconspicuous endodermis, which is much smaller than others. The type of vascular bundles of Polygonati Odorati Rhizoma is closed collateral, but the other is amphivasal. Raphides of calcium oxalate are scattered, but Raphides of the other two are like brooms and neat rows. GC-MS analysis of essential oil could provide different characteristics to distinguish three species. Twenty-three compounds were identified from essential oil of Polygonati Odorati Rhizoma and the main components were n-hexadecanoic acid (49.45%), while n-hexadecanoic acid of the other two are 23.92% and 9.45%. The content of n-hexadecanoic is strongly different. This research was aimed to establish a method by pharmacognosy and GC-MS analysis to identify three CMM and for providing scientifical data to ensure accuracy of origin of three species.

Implantation of human umbilical cord mesenchymal stem cells for ischemic stroke: perspectives and challenges.

Ischemic stroke is a focal cerebral insult that often leads to many adverse neurological complications severely affecting the quality of life. The prevalence of stroke is increasing throughout the world, while the efficacy of current pharmacological therapies remains unclear. As a neuroregenerative therapy, the implantation of human umbilical cord mesenchymal stem cells (hUC-MSCs) has shown great possibility to restore function after stroke. This review article provides an update role of hUC-MSCs implantation in the treatment of ischemic stroke. With the unique "immunosuppressive and immunoprivilege" property, hUC-MSCs are advised to be an important candidate for allogeneic cell treatment. Nevertheless, most of the treatments are still at primary stage and not clinically feasible at the current time. Several uncertain problems, such as culture conditions, allograft rejection, and potential tumorigenicity, are the choke points in this cellular therapy. More preclinical researches and clinical studies are needed before hUC-MSCs implantation can be used as a routinely applied clinical therapy.

Mitochondrial pathology in osteoarthritic chondrocytes.

Osteoarthritis (OA) is a chronic degenerative disease leading to aberrance of cartilage structures with unclear or multifactorial mechanisms. Recently, a great portion of research endeavor to explore the molecular mechanisms of OA in focusing on the mitochondrial pathology. Mitochondrial respiratory chain (MRC) produces reactive oxygen species (ROS), which in turn impair mtDNA integrity and link to cartilage degradation in OA. The fine-tuning between ROS and antioxidant within chondrocytes ensures cartilage homeostasis. With disturbance from pro-inflammatory cytokines, oxidative stress synergistically instigates cellular signaling and exacerbates mitochondrial pathology, which may affect several pathways implicated in OA cartilage degradation, including oxidative stress, increase of cytokine-induced chondrocytes inflammation and matrix catabolism, aging and senescence, obesity-related pathology, and cartilage matrix calcification. Unveiling the molecular mechanisms of mitochondrial function in OA pathogenesis and progression is essential for providing relevant therapeutic targets. These suggest that efficient protection and improvement of mitochondrial activity can be a therapeutic alternative for OA patients.

Preparation and characterization of zedoary turmeric oil-loaded insulin-modified sterically stabilized liposomes.

The poor selectivity of anticancer drugs often leads to their multiplicate dose-limiting toxicities in humans, which severely restricts their clinical application. In this study, a novel liposomal formulation of zedoary turmeric oil (ZTO) targeting the insulin receptor (IR) was prepared by covalently conjugating insulin to the terminal of the polyethylene glycol (PEG) chain of sterically stabilized liposomes. In vitro assays indicated that a higher uptake of insulin-modified sterically stabilized liposomes (ISSLs) was observed in SMMC-7721 hepatocarcinoma cells overexpressing insulin receptors. IC(50) values of ISSLs, NTLs (nontargeted liposomes), and ZTO injection (free ZTO) against SMMC-7721, determined by MTT assays, were 157.2, 256.7, and 43.3 microg x ml(-1), respectively. Plasma-clearance profiles of ZTO in the liposomal formulations were then compared with that of ZTO injection. The liposomal formulations showed much longer terminal half-lives (11.24 and 14.73 hours for ISSLs and NTLs, respectively) than that of ZTO injection (1.45 hours). All results above indicated the ISSLs were potentially useful for the treatment of IR (+) tumors and are worthy of further investigation.