Differential network analysis reveals the key role of the ECM-receptor pathway in α-particle-induced malignant transformation.

Space particle radiation is a major environmental factor in spaceflight, and it is known to cause body damage and even trigger cancer, but with unknown molecular etiologies. To examine these causes, we developed a systems biology approach by focusing on the co-expression network analysis of transcriptomics profiles obtained from single high-dose (SE) and multiple low-dose (ME) α-particle radiation exposures of BEAS-2B human bronchial epithelial cells. First, the differential network and pathway analysis based on the global network and the core modules showed that genes in the ME group had higher enrichment for the extracellular matrix (ECM)-receptor interaction pathway. Then, collagen gene COL1A1 was screened as an important gene in the ME group assessed by network parameters and an expression study of lung adenocarcinoma samples. COL1A1 was found to promote the emergence of the neoplastic characteristics of BEAS-2B cells by both in vitro experimental analyses and in vivo immunohistochemical staining. These findings suggested that the degree of malignant transformation of cells in the ME group was greater than that of the SE, which may be caused by the dysregulation of the ECM-receptor pathway.

RAI2 acts as a tumor suppressor with functional significance in gastric cancer.

Metastasis of gastric cancer (GC) is one of the major causes of death among GC patients. GC metastasis involves numerous biological processes, yet the specific molecular biological mechanisms have not been elucidated. Here, we report a novel tumor suppressor, retinoic acid-induced 2 (RAI2), which is located in the Xp22 region of the chromosome and plays a role in inhibiting GC growth and invasion. In this study, integrated analysis of The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) datasets and immunohistochemistry staining data suggested that RAI2 expression in GC samples was low. Moreover, the immune infiltration analysis indicated that low expression of RAI2 in GC was associated with a higher intensity of tumor-infiltrating lymphocytes (TILs) and an abundance of Programmed death ligand 1 (PD-L1) expression. Gene set enrichment analysis (GSEA) analysis further revealed that RAI2 regulated some pathways including the GAP junction, focal adhesion and ECM receptor interaction pathway, immune regulation, PI3K-Akt signaling, MAPK signaling, cell cycle, and DNA replication. Furthermore, the knockdown of RAI2 promoted GC cell proliferation, migration, and invasion in vitro. Taken together, these results suggest that the tumor suppressor RAI2 could be a potential target for the development of anti-cancer strategies in GC.

The Tumorigenic Effect of lncRNA AFAP1-AS1 is Mediated by Translated Peptide ATMLP Under the Control of m6 A Methylation.

Long noncoding RNAs (lncRNAs) in eukaryotic transcripts have long been believed to regulate various aspects of cellular processes, including carcinogenesis. Herein, it is found that lncRNA AFAP1-AS1 encodes a conserved 90-amino acid peptide located on mitochondria, named lncRNA AFAP1-AS1 translated mitochondrial-localized peptide (ATMLP), and it is not the lncRNA but the peptide that promotes the malignancy of nonsmall cell lung cancer (NSCLC). As the tumor progresses, the serum level of ATMLP increases. NSCLC patients with high levels of ATMLP display poorer prognosis. Translation of ATMLP is controlled by m6 A methylation at the 1313 adenine locus of AFAP1-AS1. Mechanistically, ATMLP binds to the 4-nitrophenylphosphatase domain and non-neuronal SNAP25-like protein homolog 1 (NIPSNAP1) and inhibits its transport from the inner to the outer mitochondrial membrane, which antagonizes the NIPSNAP1-mediated regulation of cell autolysosome formation. The findings uncover a complex regulatory mechanism of NSCLC malignancy orchestrated by a peptide encoded by a lncRNA. A comprehensive judgment of the application prospects of ATMLP as an early diagnostic biomarker for NSCLC is also made.

A vasculogenic mimicry prognostic signature associated with immune signature in human gastric cancer.

Background: Gastric cancer (GC) is one of the most lethal malignant tumors worldwide with poor outcomes. Vascular mimicry (VM) is an alternative blood supply to tumors that is independent of endothelial cells or angiogenesis. Previous studies have shown that VM was associated with poor prognosis in patients with GC, but the underlying mechanisms and the relationship between VM and immune infiltration of GC have not been well studied. Methods: In this study, expression profiles from VM-related genes were retrieved from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Cox regression was performed to identify key VM-related genes for survival. Subsequently, a novel risk score model in GC named VM index and a nomogram was constructed. In addition, the expression of one key VM-related gene (serpin family F member 1, SERPINF1) was validated in 33 GC tissues and 23 paracancer tissues using immunohistochemistry staining. Results: Univariate and multivariate Cox regression suggested that SERPINF1 and tissue factor pathway inhibitor 2 (TFPI2) were independent risk factors for the prognosis of patients with GC. The AUC (> 0.7) indicated the satisfactory discriminative ability of the nomogram. SsGESA and ESTIMATE showed that higher expression of SERPINF1 and TFPI2 is associated with immune infiltration of GC. Immunohistochemistry staining confirmed that the expression of SERPINF1 protein was significantly higher in GC tissues than that in paracancer tissues. Conclusion: A VM index and a nomogram were constructed and showed satisfactory predictive performance. In addition, VM was confirmed to be widely involved in immune infiltration, suggesting that VM could be a promising target in guiding immunotherapy. Taken together, we identified SERPINF1 and TFPI2 as immunologic and prognostic biomarkers related to VM in GC.

CCL8 as a promising prognostic factor in diffuse large B-cell lymphoma via M2 macrophage interactions: A bioinformatic analysis of the tumor microenvironment.

Backgrounds: Prior investigations of the tumor microenvironment (TME) of diffuse large B-cell lymphoma (DLBCL) have shown that immune and stromal cells are key contributing factors to patients' outcome. However, challenges remain in finding reliable prognostic biomarkers based on cell infiltration. In this study, we attempted to shed some light on chemokine C-C motif chemokine ligand 8 (CCL8) in DLBCL via interaction with M2 macrophages. Methods: The Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) algorithm was applied to evaluate immune and stromal scores from transcriptomic profiles of 443 DLBCL samples from The Cancer Genome Atlas (TCGA) and GSE10846 datasets. Immune cell infiltration (ICI) clusters were obtained based on different immune cell infiltrations of each sample, and gene clusters were derived through differentially expressed genes (DEGs) between the distinct ICI clusters. Five immune-related hub genes related to overall survival (OS) and clinical stages were obtained by COX regression analysis and protein-protein interaction (PPI) network construction then verified by quantitative real-time PCR (qPCR) and immunofluorescence staining in the FFPE tissues. The Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and TIMER websites were employed to explore the biological functions of CCL8-related DEGs. Uni- and multivariable Cox regression analyses were performed to analyze CCL8 as an independent prognostic risk factor in GSE10846 and were verified in other independent GEO cohorts. Results: A higher stromal score was associated with favorable prognosis in DLBCL. Patients in the ICI B cluster and gene B clusters had a better follow-up status with a higher programmed death ligand 1 (PD-L1) and cytotoxic T-lymphocyte antigen 4 (CTLA4) expression. Most of ICI-related DEGs were enriched for immune-related signaling pathways. Five hub genes with a distinct prognosis association were identified, including CD163, which is a biomarker of M2 macrophages, and CCL8. Abundant M2 macrophages were discovered in the high-CCL8 expression group. The functional analysis indicated that CCL8 is a key component of immune-related processes and secretory granule groups. Cox regression analysis and data from other GSE datasets yielded additional evidence of the prognostic value of CCL8 in DLBCL. Conclusions: CCL8 has been implicated in macrophage recruitment in several solid tumors, and only a few reports have been published on the role of CCL8 in the pathogenesis of hematological malignancies. This article attempted to find out TME-related genes that associated with the survival in DLBCL patients. CCL8 was identified to be involved in immune activities. Importantly, a series of bioinformatics analysis indicated that CCL8 might become an effective target for DLBCL, which interacts with M2 macrophage and immune checkpoint. The potential related mechanisms need to be further elucidated.

Integrative analysis of TNFRSF6B as a potential therapeutic target for pancreatic cancer.

BACKGROUND: Pancreatic cancer is one of the most lethal malignant tumors worldwide with poor outcomes. Previous studies have shown that tumor necrosis factor receptor superfamily member 6b (TNFRSF6B) plays an important role in cancer progression and immunosuppression. However, the mechanisms by which TNFRSF6B influence pancreatic cancer, and the regulatory networks involved remain to be further studied. METHODS: This study analyzed the mRNA information and clinical data of patients from The Cancer Genome Atlas (TCGA) and the ONCOMINE databases. The gene co-expression data regarding TNFRSF6B was obtained from the c-BioPortal and used to explore the functional network of TNFRSF6B in pancreatic cancer, as well as its function in tumor immunity. Short hairpin (sh) RNA knock-down experiments were performed to examine the functional roles of TNFRSF6B in pancreatic cancer cell lines. RESULTS: The expression of TNFRSF6B was elevated in pancreatic cancer tissues compared to normal pancreatic tissues, and its high expression was associated with poor prognosis of patients with pancreatic cancer. TNFRSF6B was found to be widely involved in cell cycle processes, apoptosis, apoptosis signaling pathways, immune responses, and responses to interferon. Knock-down of TNFRSF6B expression inhibited pancreatic cancer cell proliferation and invasion in vitro. Moreover, carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) was found to be co-expressed with TNFRSF6B, and there was a positive correlation between these molecules in pancreatic cancer cells. CONCLUSIONS: This report suggested that TNFRSF6B has a critical role in the progression and metastasis of pancreatic cancer. These findings provide novel insights into the role of TNFRSF6B in the functional network of pancreatic cancer, and suggest that TNFRSF6B may be a potential therapeutic target.

Identification of the miRNA signature and key genes in colorectal cancer lymph node metastasis.

BACKGROUND: Because its metastasis to the lymph nodes are closely related to poor prognosis, miRNAs and mRNAs can serve as biomarkers for the diagnosis, prognosis, and therapy of colorectal cancer (CRC). This study aimed to identify novel gene signatures in the lymph node metastasis of CRC. METHODS: GSE56350, GSE70574, and GSE95109 datasets were downloaded from the Gene Expression Omnibus (GEO) database, while data from 569 colorectal cancer cases were also downloaded from The Cancer Genome Atlas (TCGA) database. Differentially expressed miRNAs (DE-miRNAs) were calculated using R programming language (Version 3.6.3), while gene ontology and enrichment analysis of target mRNAs were performed using FunRich ( http://www.funrich.org ). Furthermore, the mRNA-miRNA network was constructed using Cytoscape software (Version 3.8.0). Gene expression levels were verified using the GEO datasets. Similarly, quantitative real-time PCR (qPCR) was used to examine expression profiles from 20 paired non-metastatic and metastatic lymph node tissue samples obtained from patients with CRC. RESULTS: In total, five DE-miRNAs were selected, and 34 mRNAs were identified after filtering the results. Moreover, two key miRNAs (hsa-miR-99a, hsa-miR-100) and one gene (heparan sulfate-glucosamine 3-sulfotransferase 2 [HS3ST2]) were identified. The GEO datasets analysis and qPCR results showed that the expression of key miRNA and genes were consistent with that obtained from the bioinformatic analysis. A novel miRNA-mRNA network capable of predicting the prognosis and confirmed experimentally, hsa-miR-99a-HS3ST2-hsa-miR-100, was found after expression analysis in metastasized lymph node tissue from CRC samples. CONCLUSION: In summary, miRNAs and genes with potential as biomarkers were found and a novel miRNA-mRNA network was established for CRC lymph node metastasis by systematic bioinformatic analysis and experimental validation. This network may be used as a potential biomarker in the development of lymph node metastatic CRC.

Why MUC16 mutations lead to a better prognosis: A study based on The Cancer Genome Atlas gastric cancer cohort.

BACKGROUND: MUC16, encoding cancer antigen 125, is a frequently mutated gene in gastric cancer. In addition, MUC16 mutations seem to result in a better prognosis in gastric cancer. However, the mechanisms that lead to a better prognosis by MUC16 mutations have not yet been clarified. AIM: To delve deeper into the underlying mechanisms that explain why MUC16 mutations signal a better prognosis in gastric cancer. METHODS: We used multi-omics data, including mRNA, simple nucleotide variation, copy number variation and methylation data from The Cancer Genome Atlas, to explore the relationship between MUC16 mutations and prognosis. Cox regression and random survival forest algorithms were applied to search for hub genes. Gene set enrichment analysis was used to elucidate the molecular mechanisms. Single-sample gene set enrichment analysis and "EpiDISH" were used to assess immune cells infiltration, and "ESTIMATE" for analysis of the tumor microenvironment. RESULTS: Our study found that compared to the wild-type group, the mutation group had a better prognosis. Additional analysis indicated that the MUC16 mutations appear to activate the DNA repair and p53 pathways to act as an anti-tumor agent. We also identified a key gene, NPY1R (neuropeptide Y receptor Y1), which was significantly more highly expressed in the MUC16 mutations group than in the MUC16 wild-type group. The high expression of NPY1R predicted a poorer prognosis, which was also confirmed in a separate Gene Expression Omnibus cohort. Further susceptibility analysis revealed that NPY1R might be a potential drug target for gastric cancer. Furthermore, in the analysis of the tumor microenvironment, we found that immune cells in the mutation group exhibited higher anti-tumor effects. In addition, the tumor mutation burden and cancer stem cells index were also higher in the mutation group than in the wild-type group. CONCLUSION: We speculated that the MUC16 mutations might activate the p53 pathway and DNA repair pathway: alternatively, the tumor microenvironment may be involved.

Development and Validation of a Nomogram Based on Nutritional Indicators and Tumor Markers for Prognosis Prediction of Pancreatic Ductal Adenocarcinoma.

PURPOSE: This study aimed to develop and validate a nomogram with preoperative nutritional indicators and tumor markers for predicting prognosis of patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: We performed a bicentric, retrospective study including 155 eligible patients with PDAC. Patients were divided into a training group (n = 95), an internal validation group (n = 34), an external validation group (n = 26), and an entire validation group (n = 60). Cox regression analysis was conducted in the training group to identify independent prognostic factors to construct a nomogram for overall survival (OS) prediction. The performance of the nomogram was assessed in validation groups and through comparison with controlling nutritional status (CONUT) and prognostic nutrition index (PNI). RESULTS: The least absolute shrinkage and selection operator (LASSO) regression, univariate and multivariate Cox regression analysis revealed that serum albumin and lymphocyte count were independent protective factors while CA19-9 and diabetes were independent risk factors. The concordance index (C-index) of the nomogram in the training, internal validation, external validation and entire validation groups were 0.777, 0.769, 0.759 and 0.774 respectively. The areas under curve (AUC) of the nomogram in each group were 0.861, 0.845, 0.773, and 0.814. C-index and AUC of the nomogram were better than those of CONUT and PNI in the training and validation groups. The net reclassification index (NRI), integrated discrimination improvement (IDI) and decision curve analysis showed improvement of accuracy of the nomogram in predicting OS and better net benefit in guiding clinical decisions in comparison with CONUT and PNI. CONCLUSIONS: The nomogram incorporating four preoperative nutritional and tumor markers including serum albumin concentration, lymphocyte count, CA19-9 and diabetes mellitus could predict the prognosis more accurately than CONUT and PNI and may serve as a clinical decision support tool to determine what treatment options to choose.

Metachronous pulmonary and pancreatic metastases arising from sigmoid colon cancer: A case report.

BACKGROUND: Metachronous pulmonary and pancreatic metastases from colorectal cancer are rare. The diagnosis of pancreatic metastases is difficult and predominantly relies on computed tomography, pathology and immunohistochemistry. Here, we describe the use of next-generation sequencing (NGS) for determination of the origin of metastasis and prognostic prediction of colorectal cancer. CASE SUMMARY: A 59-year-old man was diagnosed with sigmoid adenocarcinoma stage IIA (T3N0M0) and underwent surgery in April 2014, followed by XELOX adjuvant chemotherapy. The patient developed pulmonary metastasis in the right upper lung and underwent surgery in May 2016 without further adjuvant chemotherapy. In May 2018, pancreatic metastasis was found and he underwent pancreaticoduodenectomy. After surgery, he was treated with adjuvant S-1 chemotherapy from June 2018 to March 2019. Histopathological review of the specimens from all three lesions indicated consistent patterns characteristic of colon cancer. Concordant gene mutation profiles were observed across the three lesions that included oncogenic driver mutations most frequently seen in colon cancer (e.g., APC, TP53, KRAS and FBXW7). Blood circulating tumor (ct)DNA before adjuvant chemotherapy was undetectable with NGS, suggesting a favorable response to chemotherapy. The patient was alive and well at the latest follow-up visit, achieving a disease-free survival of 17 mo. CONCLUSION: The genetic profiles of primary tumor, metastases and ctDNA may have clinical value in auxiliary diagnosis, prognosis and therapeutic decision-making.

The long noncoding RNA CRYBG3 induces aneuploidy by interfering with spindle assembly checkpoint via direct binding with Bub3.

Aneuploidy is a hallmark of genomic instability that leads to tumor initiation, progression, and metastasis. CDC20, Bub1, and Bub3 form the mitosis checkpoint complex (MCC) that binds the anaphase-promoting complex or cyclosome (APC/C), a crucial factor of the spindle assembly checkpoint (SAC), to ensure the bi-directional attachment and proper segregation of all sister chromosomes. However, just how MCC is regulated to ensure normal mitosis during cellular division remains unclear. In the present study, we demonstrated that LNC CRYBG3, an ionizing radiation-inducible long noncoding RNA, directly binds with Bub3 and interrupts its interaction with CDC20 to result in aneuploidy. The 261-317 (S3) residual of the LNC CRYBG3 sequence is critical for its interaction with Bub3 protein. Overexpression of LNC CRYBG3 leads to aneuploidy and promotes tumorigenesis and metastasis of lung cancer cells, implying that LNC CRYBG3 is a novel oncogene. These findings provide a novel mechanistic basis for the pathogenesis of NSCLC after exposure to ionizing radiation as well as a potential target for the diagnosis, treatment, and prognosis of an often fatal disease.

Correction: The lipogenic LXR-SREBF1 signaling pathway controls cancer cell DNA repair and apoptosis and is a vulnerable point of malignant tumors for cancer therapy.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The lipogenic LXR-SREBF1 signaling pathway controls cancer cell DNA repair and apoptosis and is a vulnerable point of malignant tumors for cancer therapy.

Cancer cells are defective in DNA repair, so they experience increased DNA strand breaks, genome instability, gene mutagenesis, and tumorigenicity; however, multiple classic DNA repair genes and pathways are strongly activated in malignant tumor cells to compensate for the DNA repair deficiency and gain an apoptosis resistance. The mechanisms underlying this phenomenon in cancer are unclear. We speculate that a key DNA repair gene or signaling pathway in cancer has not yet been recognized. Here, we show that the lipogenic liver X receptor (LXR)-sterol response element binding factor-1 (SREBF1) axis controls the transcription of a key DNA repair gene polynucleotide kinase/phosphatase (PNKP), thereby governing cancer cell DNA repair and apoptosis. Notably, the PNKP levels were significantly reduced in 95% of human pancreatic cancer (PC) patients, particularly deep reduction for sixfold in all of the advanced-stage PC cases. PNKP is also deficient in three other types of cancer that we examined. In addition, the expression of LXRs and SREBF1 was significantly reduced in the tumor tissues from human PC patients compared with the adjacent normal tissues. The newly identified LXR-SREBF1-PNKP signaling pathway is deficient in PC, and the defect in the pathway contributes to the DNA repair deficiency in the cancer. Strikingly, further diminution of the vulnerable LXR-SREBF1-PNKP signaling pathway using a small molecule triptonide, a new LXR antagonist identified in this investigation, at a concentration of 8 nM robustly activated tumor-suppressor p53 and readily elevated cancer cell DNA strand breaks over an apoptotic threshold, and selectively induced PC cell apoptosis, resulting in almost complete elimination of tumors in xenograft mice without obvious complications. Our findings provide new insight into DNA repair and apoptosis in cancer, and offer a new platform for developing novel anticancer therapeutics.

Triptonide effectively suppresses gastric tumor growth and metastasis through inhibition of the oncogenic Notch1 and NF-κB signaling pathways.

Gastric cancer ranks as the third leading cause of cancer-related death worldwide. The uncontrolled tumor growth and robust metastasis are key factors to cause the cancer patient death. Mechanistically, aberrant activation of Notch and NF-κB signaling pathways plays pivotal roles in the initiation and metastasis of gastric cancer. Despite great efforts have been made in recent decades, the effective drug against the advanced and metastatic gastric cancer is still lacking in the clinical setting. In this study, we found that triptonide, a small molecule (MW358) purified from the traditional Chinese medicinal herb Tripterygium wilfordii Hook F, effectively suppressed tumor growth and metastasis in xenograft mice without obvious toxicity at the doses we tested, resulting in potent anti-gastric cancer effect with low toxicity. Triptonide markedly inhibited human metastatic gastric cancer cell migration, invasion, proliferation, and tumorigenicity. Molecular mechanistic studies revealed that triptonide significantly reduced Notch1 protein levels in metastatic gastric cancer cells through degrading the oncogenic protein Notch1 via the ubiquitin-proteasome pathway. Consequently, the levels of Notch1 downstream proteins RBPJ, IKKα, IKKß were significantly diminished, and nuclear factor-kappa B (NF-κB) phosphorylation was significantly reduced. Together, triptonide effectively suppresses gastric cancer growth and metastasis via inhibition of the oncogenic Notch1 and NF-κB signaling pathways. Our findings provide a new strategy and drug candidate for treatment of the advanced and metastatic gastric cancer.

Selective activation of tumor-suppressive MAPKP signaling pathway by triptonide effectively inhibits pancreatic cancer cell tumorigenicity and tumor growth.

The mitogen-activated protein kinase (MAPK, 1K) family members ERK, JNK, and p38 play a divergent role in either promoting tumorigenesis or tumor-suppression. Activation of ERK and JNK promotes tumorigenesis; whereas, escalation of p38 inhibits carcinogenesis. As these three MAPK members are controlled by the common up-stream MAPK signaling proteins which consist of MAPK kinases (2K) and MAPK kinase kinases (3K), how to selectively actuate tumor-suppressive p38, not concurrently stimulate tumorigenic ERK and JNK, in cancer cells is a challenge for cancer researchers, and a new opportunity for novel anti-cancer drug discovery. Using human pancreatic cancer cells and xenograft mice as models, we found that a small molecule triptonide first discerningly activated the up-stream MAPK kinase kinase MEKK4, not the other two 3K members ASK1 and GADD45; and then selectively actuated the middle stream MAPK kinase MKK4, not the other two 2K members MKK3 and MKK6; and followed by activation of the MAPK member p38, not the other two members ERK and JNK. These data suggest that triptonide is a selective MEKK4-MKK4-p38 axis agonist. Consequently, selective activation of the MEKK4-MKK4-p38 signaling axis by triptonide activated tumor suppressor p21 and inhibited CDK3 expression, resulting in cancer cell cycle arrest at G2/M phase and marked inhibition of pancreatic cancer cell tumorigenic capability in vitro and tumor growth in xenograft mice. Our findings support the notion that selective activation of tumor-suppressive MEKK4-MKK4-p38-p21signaling pathway by triptonide is a new approach for pancreatic cancer therapy, providing a new drug candidate for development of novel anti-cancer therapeutics.

Triptonide inhibits lung cancer cell tumorigenicity by selectively attenuating the Shh-Gli1 signaling pathway.

Lung cancer is a leading lethal disease with a 5-year survival rate of only 16%. Inadequate potent anti-cancer drugs appear to be a bottleneck in the treatment of lung cancer; hence, how to develop effective anti-lung cancer therapeutics is an urgent problem. In this study, we aim to explore a novel compound with potent anti-lung cancer effect and study its anti-cancer mechanisms. We found that triptonide at very low concentrations of 5-10 nM caused a marked suppression of cell proliferation and colony formation of lung cancer cells. More interestingly, triptonide also robustly inhibited the lung cancer cell formation of tumor spheres, and reduced the stemness and tumorigenicity of the sphere-forming cells. In vivo studies showed that administration of triptonide significantly inhibited the tumor growth with low toxicity. Molecular mechanistic studies revealed that triptonide significantly decreased expression of the Gli1 at both mRNA and protein levels by repressing Gli1 gene promoter activity. Additionally, triptonide reduced the levels of cancer stem cell key signaling protein sonic hedgehog (Shh), but increased the amount of Ptch1, a protein binding to SMO to diminish the Shh signal transduction, thus inhibition of the Shh-Gli1 signaling pathway. Together, our findings show that triptonide effectively inhibits lung cancer cell growth, stemness, and tumorigenicity, and support the notion that triptonide is a new Shh-Gli1 signaling inhibitor and a novel anti-lung cancer drug candidate for further developing effective lung cancer therapeutics.

Lycorine inhibits melanoma cell migration and metastasis mainly through reducing intracellular levels of ß-catenin and matrix metallopeptidase 9.

Metastatic melanoma accounts for 60% of death for skin cancer. Although great efforts have been made to treat the disease, effective drugs against metastatic melanoma still lack at the clinical setting. In the current study, we found that lycorine, a small molecule of isoquinoline alkaloid, significantly suppressed melanoma cell migration and invasion in vitro, and decreased the metastasis of melanoma cells to lung tissues in tumor-bearing mice, resulting in significant prolongation of the survival of the mice without obvious toxicity. Molecular mechanistic studies revealed that lycorine significantly reduced intracellular levels of ß-catenin protein through degradation of the protein via the ubiquitin-proteasome pathway, and decreased the expression of ß-catenin downstream prometastatic matrix metallopeptidase 9 and Axin2 genes. Collectively, our findings support the notion that targeting the oncogenic ß-catenin by lycorine is a new option to inhibit melanoma cell metastasis, providing a good drug candidate potential for development novel therapeutics against metastatic melanoma.

Atorvastatin enhances endothelial adherens junctions through promoting VE-PTP gene transcription and reducing VE-cadherin-Y731 phosphorylation.

Vascular endothelial protein tyrosine phosphatase (VE-PTP) is essential for endothelial cells (ECs) adherens junction and vascular homeostasis; however, the regulatory mechanism of VE-PTP transcription is unknown, and a drug able to promote VE-PTP expression in ECs has not yet been reported in the literature. In this study, we used human ECs as a model to explore small molecule compounds able to promote VE-PTP expression, and found that atorvastatin, a HMG-CoA reductase inhibitor widely used in the clinic to treat hypercholesterolemia-related cardiovascular diseases, strongly promoted VE-PTP transcription in ECs through activating the VE-PTP promoter and upregulating the expression of the transcription factor, specificity protein 1 (SP1). Additionally, atorvastatin markedly reduced VE-cadherin-Y731 phosphorylation induced by cigarette smoke extract and significantly enhanced stability of endothelial adherens junctions. Together, our findings reveal that atorvastatin up-regulates VE-PTP expression, increases VE-cadherin protein levels, and decreases VE-cadherin-Y731 phosphorylation to strengthen EC adherens junctions and maintain vascular cell monolayer integrity, offering a new mechanism of atorvastatin against CSE-induced disruption of vascular integrity and relevant cardio-cerebrovascular disease.

Triptonide potently suppresses pancreatic cancer cell-mediated vasculogenic mimicry by inhibiting expression of VE-cadherin and chemokine ligand 2 genes.

Various aggressive cancers, including pancreatic cancer, produce functional blood vessels by neovascularization. Tumor vasculogenic mimicry (VM) promotes cancer progression and is closely associated with the poor prognosis of the cancer patients. Therefore, tumor VM is a sensible target for novel anti-cancer drug discovery. However, there is a lack of effective anti-tumor VM drugs in the clinical setting. In this study, we aim to explore novel agents to effectually inhibit pancreatic cancer cell-mediated tumor VM for anti-cancer therapy. Pancreatic cancer cell lines Patu8988 and Panc1 were utilized as a model. A mouse model was used for in vitro capillary-like structure formation and in vivo Matrigel plug assays to evaluate the anti-tumor VM efficacy of a small molecule triptonide from traditional Chinese herbs. Various methods, including RT-PCR, immunohistochemical staining, and the luciferase gene transcription reporter system, were applied to study the mechanisms of triptonide-exerted anti-tumor VM. Triptonide effectively inhibited pancreatic cancer cell-formed capillary-like structures in vitro and blood vessels in vivo through suppressing pancreatic cancer cell migration, invasion, and VM via inhibiting expression of tumor VM master gene VE-cadherin and pro-migratory gene chemokine C-X-C motif ligand 2 (CXCL2), mainly via reduction of gene promoter activity. Triptonide potently suppresses pancreatic cancer cell-mediated VM by reducing tumor cell migration and invasion and inhibiting expression of VE-cadherin and CXCL2 genes. Our results provide a novel and potent anti-tumor VM drug candidate for further development of effective anti-pancreatic cancer therapy.