Dendrobium nobile active ingredient Dendrobin A against hepatocellular carcinoma via inhibiting nuclear factor kappa-B signaling.

OBJECTIVE: Dendrobin A, a typical active ingredient of the traditional Chinese medicine Dendrobium nobile, has potential clinical application in cancer treatment; however, its effect and mechanism in anti-hepatocellular carcinoma (HCC) remain unsolved. METHOD: The effects of Dendrobin A on the viability, migration, invasion, cycle, apoptosis, and epithelial-mesenchymal transition of HepG2 and SK-HEP-1 cells were verified by in vitro experiments. mRNA sequencing was performed to screen the differentially expressed genes (DEGs) of HCC cells before and after Dendrobin A treatment, following GO enrichment and KEGG signaling pathway analyses. Mechanistically, molecular docking was used to evaluate the binding of Dendrobin A with proteins p65 and p50, before further verifying the activation of nuclear factor kappa-B (NF-κB) signaling. Finally, the antiproliferative effect of Dendrobin A on HCC cells was explored through animal experiments. RESULTS: Dendrobin A arrested cell cycle, induced apoptosis, and inhibited proliferation, migration, invasion, and blocked epithelial-mesenchymal transition in HepG2 and SK-HEP-1 cells. mRNA sequencing identified 830 DEGs, involving various biological processes. KEGG analysis highlighted NF-κB signaling. Molecular docking revealed strong binding of Dendrobin A with p65 and p50 proteins, and western blotting confirmed reduced levels of p-p65 and p-p50 in HCC cells post Dendrobin A treatment. NF-κB agonist PMA reversed Dendrobin A-inhibited cell proliferation migration and invasion. In vivo experiments showed that Dendrobin A inhibited HCC cell growth. CONCLUSION: Our findings suggest that Dendrobin A exhibits anti-HCC properties by inhibiting the activation of the NF-κB pathway. These results provide a scientific basis for utilizing Dendrobium nobile in anti-HCC therapies.

Glucose dysregulation promotes oncogenesis in human bladder cancer by regulating autophagy and YAP1/TAZ expression.

Glucose dysregulation is strongly correlated with cancer development, and cancer is prevalent in patients with Type 2 diabetes (T2D). We aimed to elucidate the mechanism underlying autophagy in response to glucose dysregulation in human bladder cancer (BC). 220 BC patients were included in this retrospective study. The expression of YAP1, TAZ and AMPK, EMT-associated markers, and autophagy marker proteins was analysed by immunohistochemistry, western blotting, and quantitative real-time PCR (qPCR). Further, T24 and UMUC-3 BC cells were cultured in media with different glucose concentrations, and the expression of YAP1, TAZ, AMPK and EMT-associated markers, and autophagy marker proteins was analysed by western blotting and qPCR. Autophagy was observed by immunofluorescence and electron microscopy. BC cell viability was tested using MTT assays. A xenograft nude mouse model of diabetes was used to evaluate tumour growth, metastasis and survival. A poorer pathologic grade and tumour-node-metastasis stage were observed in patients with BC with comorbid T2D than in others with BC. YAP1 and TAZ were upregulated in BC samples from patients with T2D. Mechanistically, high glucose (HG) promoted BC progression both in vitro and in vivo and inhibited autophagy. Specifically, various autophagy marker proteins and AMPK were negatively regulated under HG conditions and correlated with YAP1 and TAZ expression. These results demonstrate that HG inhibits autophagy and promotes cancer development in BC. YAP1/TAZ/AMPK signalling plays a crucial role in regulating glucose dysregulation during autophagy. Targeting these effectors exhibits therapeutic significance and can serve as prognostic markers in BC patients with T2D.

Integrated analysis of Dendrobium nobile extract Dendrobin A against pancreatic ductal adenocarcinoma based on network pharmacology, bioinformatics, and validation experiments.

Background: Dendrobium nobile (D. nobile), a traditional Chinese medicine, has received attention as an anti-tumor drug, but its mechanism is still unclear. In this study, we applied network pharmacology, bioinformatics, and in vitro experiments to explore the effect and mechanism of Dendrobin A, the active ingredient of D. nobile, against pancreatic ductal adenocarcinoma (PDAC). Methods: The databases of SwissTargetPrediction and PharmMapper were used to obtain the potential targets of Dendrobin A, and the differentially expressed genes (DEGs) between PDAC and normal pancreatic tissues were obtained from The Cancer Genome Atlas and Genotype-Tissue Expression databases. The protein-protein interaction (PPI) network for Dendrobin A anti-PDAC targets was constructed based on the STRING database. Molecular docking was used to assess Dendrobin A anti-PDAC targets. PLAU, one of the key targets of Dendrobin A anti-PDAC, was immunohistochemically stained in clinical tissue arrays. Finally, in vitro experiments were used to validate the effects of Dendrobin A on PLAU expression and the proliferation, apoptosis, cell cycle, migration, and invasion of PDAC cells. Results: A total of 90 genes for Dendrobin A anti-PDAC were screened, and a PPI network for Dendrobin A anti-PDAC targets was constructed. Notably, a scale-free module with 19 genes in the PPI indicated that the PPI is highly credible. Among these 19 genes, PLAU was positively correlated with the cachexia status while negatively correlated with the overall survival of PDAC patients. Through molecular docking, Dendrobin A was found to bind to PLAU, and the Dendrobin A treatment led to an attenuated PLAU expression in PDAC cells. Based on clinical tissue arrays, PLAU protein was highly expressed in PDAC cells compared to normal controls, and PLAU protein levels were associated with the differentiation and lymph node metastatic status of PDAC. In vitro experiments further showed that Dendrobin A treatment significantly inhibited the proliferation, migration, and invasion, inducing apoptosis and arresting the cell cycle of PDAC cells at the G2/M phase. Conclusion: Dendrobin A, a representative active ingredient of D. nobile, can effectively fight against PDAC by targeting PLAU. Our results provide the foundation for future PDAC treatment based on D. nobile.

Integrating Network Pharmacology and Bioinformatics to Explore the Effects of Dangshen (Codonopsis pilosula) Against Hepatocellular Carcinoma: Validation Based on the Active Compound Luteolin.

Purpose: This study aimed to explore the pharmacological mechanism of Dangshen (Codonopsis pilosula) against hepatocellular carcinoma (HCC) based on network pharmacology and bioinformatics, and to verify the anticancer effect of luteolin, the active ingredient of Codonopsis pilosula, on HCC cells. Methods: The effective compounds and potential targets of Codonopsis pilosula were established using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database. The genes related to HCC were obtained through the GeneCards database. The interactive genes were imported into the Visualization and Integrated Discovery database for Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) signal enrichment, and the hub genes were screened out. The Cancer Genome Atlas database was used to construct a prognosis model, and the prognosis and clinicopathological correlation were analyzed. In in vitro experiments, we verified the effects of luteolin, an active compound of Codonopsis pilosula, on the proliferation, cell cycle, apoptosis and migration of HCC cells. Results: A total of 21 effective compounds of Codonopsis pilosula and 98 potential downstream target genes were screened through the TCMSP database, and 1406 HCC target genes were obtained through the GeneCards database. Finally, 53 interacting genes between the two databases were obtained, among which, the 10 key node genes were CASP3, TP53, MDM2, AKT1, ESR1, BCL2L1, MCL1, HSP90AA1, CASP9, and CCND1, involving 77 typical GO terms and 72 KEGG signals. The Kaplan-Meier survival curve of the model group showed that the overall survival of the low-risk group was significantly higher than that of the high-risk group. Luteolin significantly inhibited the proliferation and migration of HCC cells, induced apoptosis, and increased the G2/M phase ratio. Mechanistically, luteolin significantly inhibited the phosphorylation of MAPK-JNK and Akt (Thr308) and subsequently led to upregulation of ESR1. Pharmacological inhibition of ESR1 with fulvestrant enhanced cell viability and migration and attenuated apoptosis. Conclusion: Codonopsis pilosula has potential for clinical development due to its anti-HCC properties. Luteolin, the effective component of Codonopsis pilosula, plays anti-HCC role through AKT- or MAPK-JNK signaling mediated ESR1.

Autophagy inhibition prevents lymphatic malformation progression to lymphangiosarcoma by decreasing osteopontin and Stat3 signaling.

Lymphatic malformation (LM) is a vascular anomaly originating from lymphatic endothelial cells (ECs). While it mostly remains a benign disease, a fraction of LM patients progresses to malignant lymphangiosarcoma (LAS). However, very little is known about underlying mechanisms regulating LM malignant transformation to LAS. Here, we investigate the role of autophagy in LAS development by generating EC-specific conditional knockout of an essential autophagy gene Rb1cc1/FIP200 in Tsc1iΔEC mouse model for human LAS. We find that Fip200 deletion blocked LM progression to LAS without affecting LM development. We further show that inhibiting autophagy by genetical ablation of FIP200, Atg5 or Atg7, significantly inhibited LAS tumor cell proliferation in vitro and tumorigenicity in vivo. Transcriptional profiling of autophagy-deficient tumor cells and additional mechanistic analysis determine that autophagy plays a role in regulating Osteopontin expression and its down-stream Jak/Stat3 signaling in tumor cell proliferation and tumorigenicity. Lastly, we show that specifically disrupting FIP200 canonical autophagy function by knocking-in FIP200-4A mutant allele in Tsc1iΔEC mice blocked LM progression to LAS. These results demonstrate a role for autophagy in LAS development, suggesting new strategies for preventing and treating LAS.

Regulation of RB1CC1/FIP200 stability and autophagy function by CREBBP-mediated acetylation in an intrinsically disordered region.

RB1CC1/FIP200 is an essential macroautophagy/autophagy protein that plays an important role in a variety of biological and disease processes through its canonical autophagy-dependent and -independent functions. However, it remains largely unknown whether post-translational modifications could regulate RB1CC1 and its associated autophagy functions. Here, we report acetylation of several lysine residues of RB1CC1 by acetyltransferase CREBBP (CREB binding protein), with K276 as the major CREBBP acetylation site. K276 is also identified as a ubiquitination site by mass spectrometry, and acetylation at this site reduces ubiquitination of RB1CC1 to inhibit its ubiquitin-dependent degradation. We also find that RB1CC1 contains an N-terminal intrinsically disordered region (IDR) capable of forming liquid-liquid phase separation (LLPS) in vitro, which may drive formation of RB1CC1 puncta with LLPS properties in cells independent of SQSTM1/p62 and other autophagy receptors CALCOCO2/NDP52, NBR1, TAX1BP1 and OPTN. Mutational analysis shows that both K276 acetylation and the N-terminal IDR containing it are important for maintaining canonical autophagy function of RB1CC1 in breast cancer cells. Our findings demonstrate regulation of RB1CC1 by a new post-translational mechanism and suggest potential therapeutic application of inducing RB1CC1 degradation through blocking K276 acetylation in the treatment of cancer and other diseases.Abbreviations: Baf-A1: bafilomycin A1; CREBBP/CBP: CREB binding protein; CHX: cycloheximide; EP300/p300: E1A binding protein p300; FRAP: fluorescence recovery after photobleaching; HADCs: histone deacetylases; IDR: intrinsically disordered region; LLPS: liquid-liquid phase separation; KAT2A/GCN5: lysine acetyltransferase 2A; KAT2B/PCAF: lysine acetyltransferase 2B; KAT5/TIP60: lysine acetyltransferase 5; KAT8/MOF: lysine acetyltransferase 8; NAM: nicotinamide; PAS: phagophore assembly site; PEG-8000: polyethylene glycol 8000; RB1CC1/FIP200: RB1 inducible coiled-coil 1; TSA: trichostatin A.

AIM-CICs: an automatic identification method for cell-in-cell structures based on convolutional neural network.

Edited by Luonan Chen Whereas biochemical markers are available for most types of cell death, current studies on non-autonomous cell death by entosis rely strictly on the identification of cell-in-cell structures (CICs), a unique morphological readout that can only be quantified manually at present. Moreover, the manual CIC quantification is generally over-simplified as CIC counts, which represents a major hurdle against profound mechanistic investigations. In this study, we take advantage of artificial intelligence technology to develop an automatic identification method for CICs (AIM-CICs), which performs comprehensive CIC analysis in an automated and efficient way. The AIM-CICs, developed on the algorithm of convolutional neural network, can not only differentiate between CICs and non-CICs (the area under the receiver operating characteristic curve (AUC) > 0.99), but also accurately categorize CICs into five subclasses based on CIC stages and cell number involved (AUC > 0.97 for all subclasses). The application of AIM-CICs would systemically fuel research on CIC-mediated cell death, such as high-throughput screening.

Cell-in-cell structure mediates in-cell killing suppressed by CD44.

Penetration of immune cells into tumor cells was believed to be immune-suppressive via cell-in-cell (CIC) mediated death of the internalized immune cells. We unexpectedly found that CIC formation largely led to the death of the host tumor cells, but not the internalized immune cells, manifesting typical features of death executed by NK cells; we named this "in-cell killing" which displays the efficacy superior to the canonical way of "kiss-killing" from outside. By profiling isogenic cells, CD44 on tumor cells was identified as a negative regulator of "in-cell killing" via inhibiting CIC formation. CD44 functions to antagonize NK cell internalization by reducing N-cadherin-mediated intercellular adhesion and by enhancing Rho GTPase-regulated cellular stiffness as well. Remarkably, antibody-mediated blockade of CD44 signaling potentiated the suppressive effects of NK cells on tumor growth associated with increased heterotypic CIC formation. Together, we identified CIC-mediated "in-cell killing" as a promising strategy for cancer immunotherapy.

ZNF3 regulates proliferation, migration and invasion through MMP1 and TWIST in colorectal cancer.

Colorectal cancer (CRC) is a malignant tumor with a high incidence and mortality worldwide. Currently, the underlying molecular mechanisms of CRC are still unclear. Zinc finger protein 3 (ZNF3) is a zinc-finger transcription factor that has been reported as a candidate for breast cancer prognosis, suggesting its involvement in the regulation of tumorigenesis. However, the association between ZNF3 and CRC remains unknown. To investigate the role of ZNF3 in CRC, we first analyze the correlation between ZNF3 expression and CRC, and the results demonstrate that ZNF3 is highly expressed in CRC tissue and cells, which is associated with the age of CRC patients. In vitro studies show that ZNF3 overexpression promotes CRC cell migration. Compared to control cells, knockdown of ZNF3 markedly suppresses CRC cell proliferation, migration and invasion and promotes G0/G1 phase cell cycle arrest. The expressions of the EMT-related markers TWIST and MMP1 are significantly decreased when ZNF3 is silenced. Additionally, overexpression of MMP1 and TWIST exacerbates CRC cell proliferation, accelerates the S phase cell cycle in ZNF3-knockdown SW480 cells, and increases cell migration and invasion through Transwell chambers. These data suggest that ZNF3 is involved in cellular proliferation, migration and invasion by regulating MMP1 and TWIST in CRC cells.

p53-dependent elimination of aneuploid mitotic offspring by entosis.

Entosis was proposed to promote aneuploidy and genome instability by cell-in-cell mediated engulfment in tumor cells. We reported here, in epithelial cells, that entosis coupled with mitotic arrest functions to counteract genome instability by targeting aneuploid mitotic progenies for engulfment and elimination. We found that the formation of cell-in-cell structures associated with prolonged mitosis, which was sufficient to induce entosis. This process was controlled by the tumor suppressor p53 (wild-type) that upregulates Rnd3 expression in response to DNA damages associated with prolonged metaphase. Rnd3-compartmentalized RhoA activities accumulated during prolonged metaphase to drive cell-in-cell formation. Remarkably, this prolonged mitosis-induced entosis selectively targets non-diploid progenies for internalization, blockade of which increased aneuploidy. Thus, our work uncovered a heretofore unrecognized mechanism of mitotic surveillance for entosis, which eliminates newly born abnormal daughter cells in a p53-dependent way, implicating in the maintenance of genome integrity.

Mechanical Ring Interfaces between Adherens Junction and Contractile Actomyosin to Coordinate Entotic Cell-in-Cell Formation.

Entosis is a cell-in-cell (CIC)-mediated death program. Contractile actomyosin (CA) and the adherens junction (AJ) are two core elements essential for entotic CIC formation, but the molecular structures interfacing them remain poorly understood. Here, we report the characterization of a ring-like structure interfacing between the peripheries of invading and engulfing cells. The ring-like structure is a multi-molecular complex consisting of adhesive and cytoskeletal proteins, in which the mechanical sensor vinculin is highly enriched. The vinculin-enriched structure senses mechanical force imposed on cells, as indicated by fluorescence resonance energy transfer (FRET) analysis, and is thus termed the mechanical ring (MR). The MR actively interacts with CA and the AJ to help establish and maintain polarized actomyosin that drives cell internalization. Vinculin depletion leads to compromised MR formation, CA depolarization, and subsequent CIC failure. In summary, we suggest that the vinculin-enriched MR, in addition to CA and AJ, is another core element essential for entosis.

PCDH7 Inhibits the Formation of Homotypic Cell-in-Cell Structure.

Though homotypic cell-in-cell (hoCIC) structures are implicated in the development and progression of multiple human tumors, the molecular mechanisms underlying their formation remain poorly understood. We found that the expression of Protocadherin-7 (PCDH7), an integral membrane protein, was negatively associated with the formation of hoCIC structures. Overexpression of PCDH7 efficiently inhibits, while its depletion significantly enhances, hoCIC formation, which was attributed to its regulation on intercellular adhesion and contractile actomyosin as well. Via directly interacting with and inactivating PP1α, a protein phosphatase that dephosphorylates pMLC2, PCDH7 increases the level of pMLC2 leading to enhanced actomyosin at the intercellular region and compromised hoCIC formation. Remarkably, PCDH7 enhanced anchorage-independent cell growth in a hoCIC-dependent manner. Together, we identified PCDH7 as the first trans-membrane protein that inhibits hoCIC formation to promote tumor growth.

High Frequency of Cell-in-Cell Formation in Heterogeneous Human Breast Cancer Tissue in a Patient With Poor Prognosis: A Case Report and Literature Review.

Cell cannibalism is a unique pathological phenomenon that has been observed at low frequency in a variety of human tumor samples (<0.5%), including breast cancer. Cannibalistic cells typically form cell-in-cell (CIC) structures characterized by enclosure of one cell or more by another, mediating a novel type of cell death "entosis," which was proposed as the type IV cell death. A large number of CIC structures are generally associated with malignant transformation and progression, and they are believed to be primed by and form among heterogeneous cells. However, there is currently no in vivo evidence from human tumor samples. In this case report, covering a 37-year-old female breast cancer patient, we observed considerable heterogeneity and proliferative activity (>70% Ki-67 positivity) in her breast cancer cells, accompanied by high frequency of CIC formation (~6%) and poor prognosis. We consider this a typical example of cell cannibalism, supporting a role of heterogeneity in cell-in-cell formation and malignant progression. It may serve as a pretest basis for further investigations of cell-in-cell biology and breast cancer treatment.

Expression profiling identified IL-8 as a regulator of homotypic cell-in-cell formation.

Homotypic cell-in-cell (CIC) structures forming between cancer cells were proposed to promote tumor evolution via entosis, a nonapoptotic cell death process. However, the mechanisms underlying their formation remained poorly understood. We performed a microarray analysis to identify genes associated with homotypic CIC formation. Cancer cells differing in their ability to form homotypic CIC structures were selected for the study. Association analysis identified 73 probe sets for 62 candidate genes potentially involved in CIC formation. Among them, twenty-one genes were downregulated while 41 genes were upregulated. Pathway analysis identified a gene interaction network centered on IL-8, which was upregulated in high CIC cells. Remarkably, CIC formation was significantly inhibited by IL-8 knockdown and enhanced upon recombinant IL-8 treatment, which correlated with altered cell-cell adhesion and expression of adhesive molecules such as P-cadherin and γ-catenin. Together, our work identified IL-8 as a positive regulator of homotypic CIC formation via enhancing intercellular adhesion. [BMB Reports 2018; 51(8): 412-417].

Cholesterol inhibits entotic cell-in-cell formation and actomyosin contraction.

Cell-in-cell structure is prevalent in human cancer, and associated with several specific pathophysiological phenomena. Although cell membrane adhesion molecules were found critical for cell-in-cell formation, the roles of other membrane components, such as lipids, remain to be explored. In this study, we attempted to investigate the effects of cholesterol and phospholipids on the formation of cell-in-cell structures by utilizing liposome as a vector. We found that Lipofectamine-2000, the reagent commonly used for routine transfection, could significantly reduce entotic cell-in-cell formation in a cell-specific manner, which is correlated with suppressed actomyosin contraction as indicated by reduced ß-actin expression and myosin light chain phosphorylation. The influence on cell-in-cell formation was likely dictated by specific liposome components as some liposomes affected cell-in-cell formation while some others didn't. Screening on a limited number of lipids, the major components of liposome, identified phosphatidylethanolamine (PE), stearamide (SA), lysophosphatidic acid (LPA) and cholesterol (CHOL) as the inhibitors of cell-in-cell formation. Importantly, cholesterol treatment significantly inhibited myosin light chain phosphorylation, which resembles the effect of Lipofectamine-2000, suggesting cholesterol might be partially responsible for liposomes' effects on cell-in-cell formation. Together, our findings supporting a role of membrane lipids and cholesterol in cell-in-cell formation probably via regulating actomyosin contraction.

Optimal codons in Tremella fuciformis end in C/G, a strong difference with known Tremella species.

Tremella fuciformis is a popular edible fungus with fruiting bodies that can be produced in large quantities at low costs, while it is easy to transform and cultivate as yeast. This makes it an attractive potential bioreactor. Enhanced heterologous gene expression through codon optimization would be useful, but until now codon usage preferences in T. fuciformis remain unknown. To precisely determine the preferred codon usage of T. fuciformis we sequenced the genome of strain Tr26 resulting in a 24.2 Mb draft genome with 10,040 predicted genes. 3288 of the derived predicted proteins matched the UniProtKB/Swiss-Prot databases with 40% or more similarity. Corresponding gene models of this subset were subsequently optimized through repetitive comparison of alternative start codons and selection of best length matching gene models. For experimental confirmation of gene models, 96 random clones from an existing T. fuciformis cDNA library were sequenced, generating 80 complete CDSs. Calculated optimal codons for the 3288 predicted and the 80 cloned CDSs were highly similar, indicating sufficient accuracy of predicted gene models for codon usage analysis. T. fuciformis showed a strong preference for C and then G at the third base pair position of used codons, while average GC content of predicted genes was slightly higher than the total genome sequence average. Most optimal codons ended in C or G except for one, and an increased frequency of C ending codons was observed in genes with higher expression levels. Surprisingly, the preferred codon usage in T. fuciformis strongly differed from T. mesenterica and C. neoformans. Instead, optimal codon usage was similar to more distant related species such as Ustilago maydis and Neurospora crassa. Despite much higher overall sequence homology between T. fuciformis and T. mesenterica, only 7 out of 21 optimal codons were equal, whereas T. fuciformis shared up to 20 out of 21 optimal codons with other species. Clearly, codon usage in Tremella can differ largely and should be estimated for individual species. The precise identification of optimal and high expression related codons is therefore an important step in the development of T. fuciformis as a bioreactor system.