Dysregulation of the MiR-449b target TGFBI alters the TGFβ pathway to induce cisplatin resistance in nasopharyngeal carcinoma

Nasopharyngeal carcinoma: current views on the tumor microenvironment's impact on drug resistance and clinical outcomes

The incidence of nasopharyngeal carcinoma (NPC) exhibits significant variations across different ethnic groups and geographical regions, with Southeast Asia and North Africa being endemic areas. Of note, Epstein-Barr virus (EBV) infection is closely associated with almost all of the undifferentiated NPC cases. Over the past three decades, radiation therapy and chemotherapy have formed the cornerstone of NPC treatment. However, recent advancements in immunotherapy have introduced a range of promising approaches for managing NPC. In light of these developments, it has become evident that a deeper understanding of the tumor microenvironment (TME) is crucial. The TME serves a dual function, acting as a promoter of tumorigenesis while also orchestrating immunosuppression, thereby facilitating cancer progression and enabling immune evasion. Consequently, a comprehensive comprehension of the TME and its intricate involvement in the initiation, progression, and metastasis of NPC is imperative for the development of effective anticancer drugs. Moreover, given the complexity of TME and the inter-patient heterogeneity, personalized treatment should be designed to maximize therapeutic efficacy and circumvent drug resistance. This review aims to provide an in-depth exploration of the TME within the context of EBV-induced NPC, with a particular emphasis on its pivotal role in regulating intercellular communication and shaping treatment responses. Additionally, the review offers a concise summary of drug resistance mechanisms and potential strategies for their reversal, specifically in relation to chemoradiation therapy, targeted therapy, and immunotherapy. Furthermore, recent advances in clinical trials pertaining to NPC are also discussed.

SDPR Inhibits TGF-β Induced Cancer Metastasis Through Fatty Acid Oxidation Regulation in Gastric Cancer

Our previous studies have confirmed that transforming growth factor-β (TGF-β) plays an important role in tumor metastasis, and the serum deprivation protein response (SDPR) is a potential downstream target of TGF-β. However, the role and mechanism of SDPR in gastric cancer are still unclear. We performed gene microarray, bioinformation analysis, combined with in vivo and in vitro experimental verification, we identified that SDPR is significantly downregulated in gastric cancer, and participates in TGF-β-mediated tumour metastasis. Mechanically, SDPR interacts with extracellular signal-regulated kinase (ERK) and inhibits fatty acid metabolism key gene Carnitine palmitoyl transferase 1A (CPT1A) at transcriptional level by supressing ERK/PPAR pathway. Our findings suggest that the TGF-β/SDPR/CPT1A axis play an important role in the fatty acid oxidation of gastric cancer, and provides a new insight into the crosstalk of tumour microenvironments and metabolism reprogramming and suggest that strategies to intervene the fatty acid metabolism may therapy gastric cancer metastasis.

Identification of upregulated exosomal miRNAs between A2780 and A2780/DDP human ovarian cancer cells by high-throughput sequencing

Exosomal miRNAs are known to play important roles in ovarian cancer and chemotherapeutic resistance. However, a systematic evaluation of characteristics of exosomal miRNAs involved in cisplatin resistance in ovarian cancer remains totally unclear. Exosomes (Exo-A2780, Exo-A2780/DDP) were extracted from cisplatin-sensitive cells (A2780) and cisplatin-resistant cells (A2780/DDP). Differential exosomal miRNA expression profiles were found by high-throughput sequencing (HTS). Target genes of the exo-miRNAs were predicted by using two online databases to increase the prediction accuracy. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were utilized to find biological relationships with chemoresistance. RT‒qPCR of three exosomal miRNAs was performed, and a protein‒protein interaction (PPI) network was established to identify the hub genes. The GDSC database was used to prove the association between hsa-miR-675-3p expression and the IC50 value. An integrated miRNA-mRNA network was constructed to predict miRNA-mRNA associations. The connection between hsa-miR-675-3p and ovarian cancer was discovered by immune microenvironment analyses. The upregulated exosomal miRNAs could regulate gene targets through signalling pathways such as the Ras, PI3K/Akt, Wnt, and ErbB pathways. GO and KEGG analyses indicated that the target genes were involved in protein binding, transcription regulator activity and DNA binding. The RT‒qPCR results were consistent with the HTS data, and the results of PPI network analysis suggested that FMR1 and CD86 were the hub genes. GDSC database analysis and construction of the integrated miRNA-mRNA network suggested that hsa-miR-675-3p was associated with drug resistance. Immune microenvironment analyses showed that hsa-miR-675-3p was crucial in ovarian cancer. The study suggested that exosomal hsa-miR-675-3p is a potential target for treating ovarian cancer and overcoming cisplatin resistance.

Coinfection of Dermal Fibroblasts by Human Cytomegalovirus and Human Herpesvirus 6 Can Boost the Expression of Fibrosis-Associated MicroRNAs

Tissue fibrosis can affect every type of tissue or organ, often leading to organ malfunction; however, the mechanisms involved in this process are not yet clarified. A role has been hypothesized for Human Cytomegalovirus (HCMV) and Human Herpesvirus 6 (HHV-6) infections as triggers of systemic sclerosis (SSc), a severe autoimmune disease causing progressive tissue fibrosis, since both viruses and antiviral immune responses toward them have been detected in patients. Moreover, HCMV or HHV-6A infection was reported to increase the expression of fibrosis-associated transcriptional factors and miRNAs in human dermal fibroblasts. However, it is unlikely that they have separate effects in the infected host, as both viruses are highly prevalent in the human population. Thus, our study aimed to investigate, by quantitative real-time PCR microarray, the impact of HCMV/HHV-6A coinfection on the expression of pro-fibrotic miRNAs in coinfected cells, compared to the effect of single viruses. The results showed a possible synergistic effect of the two viruses on pro-fibrotic miRNA expression, thus suggesting that HCMV and HHV-6 may enhance each other and cooperate at inducing enhanced miRNA-driven fibrosis. These data may also suggest a possible use of virus-induced miRNAs as novel diagnostic or prognostic biomarkers for SSc and its clinical treatment.

Platinum-resistance in epithelial ovarian cancer: an interplay of epithelial-mesenchymal transition interlinked with reprogrammed metabolism

BACKGROUND

Epithelial ovarian cancer is the most lethal gynaecological cancer worldwide. Chemotherapy resistance represents a significant clinical challenge and is the main reason for poor ovarian cancer prognosis. We identified novel expression of markers related to epithelial mesenchymal transitions (EMT) in a carboplatin resistant ovarian cancer cell line by proteomics. This was validated in the platinum resistant versus sensitive parental cell lines, as well as platinum resistant versus sensitive human ovarian cancer patient samples. The prognostic significance of the different proteomics-identified marker proteins in prognosis prediction on survival as well as their correlative association and influence on immune cell infiltration was determined by public domain data bases.

METHODS

We explored the proteomic differences between carboplatin-sensitive OVCAR5 cells (parental) and their carboplatin-resistant counterpart, OVCAR5 CBPR cells. qPCR and western blots were performed to validate differentially expressed proteins at the mRNA and protein levels, respectively. Association of the identified proteins with epithelial-mesenchymal transition (EMT) prompted the investigation of cell motility. Cellular bioenergetics and proliferation were studied to delineate any biological adaptations that facilitate cancer progression. Expression of differentially expressed proteins was assessed in ovarian tumors obtained from platinum-sensitive (n = 15) versus platinum-resistant patients (n = 10), as well as matching tumors from patients at initial diagnosis and following relapse (n = 4). Kaplan-Meier plotter and Tumor Immune Estimation Resource (TIMER) databases were used to determine the prognostic significance and influence of the different proteomics-identified proteins on immune cell infiltration in the tumor microenvironment (TME).

RESULTS

Our proteomics study identified 2422 proteins in both cell lines. Of these, 18 proteins were upregulated and 14 were downregulated by ≥ twofold (p < 0.05) in OVCAR5 CBPR cells. Gene ontology enrichment analysis amongst upregulated proteins revealed an overrepresentation of biological processes consistent with EMT in the resistant cell line. Enhanced mRNA and/or protein expression of the identified EMT modulators including ITGA2, TGFBI, AKR1B1, ITGAV, ITGA1, GFPT2, FLNA and G6PD were confirmed in OVCAR5 CBPR cells compared to parental OVCAR5 cell line. Consistent with the altered EMT profile, the OVCAR5 CBPR cells demonstrated enhanced migration and reduced proliferation, glycolysis, and oxidative phosphorylation. The upregulation of G6PD, AKR1B1, ITGAV, and TGFβ1 in OVCAR5 CBPR cells was also identified in the tumors of platinum-resistant compared to platinum-sensitive high grade serous ovarian cancer (HGSOC) patients. Matching tumors of relapsed versus newly diagnosed HGSOC patients also showed enhanced expression of AKR1B1, ITGAV, TGFβ1 and G6PD protein in relapsed tumors. Among the identified proteins, significant enhanced expression of GFPT2, FLNA, TGFBI (CDGG1), ITGA2 predicted unfavorable prognosis in ovarian cancer patients. Further analysis suggested that the expression of TGFBI to correlate positively with the expression of identified and validated proteins such as GFPT2, FLNA, G6PD, ITGAV, ITGA1 and ITGA2; and with the infiltration of CD8⁺ T cells, macrophages, neutrophils, and dendritic cells in the TME.

CONCLUSIONS

Our research demonstrates proteomic-based discovery of novel EMT-related markers with an altered metabolic profile in platinum-resistant versus sensitive ovarian cancer cell lines. The study also confirms the expression of selected identified markers in the tumors of platinum-resistant versus sensitive, and in matching relapsed versus newly diagnosed HGSOC patients. The study provides insights into the metabolic adaptation of EMT-induced carboplatin resistant cells that confers on them reduced proliferation to provide effective migratory advantage; and the role of some of these identified proteins in ovarian cancer prognosis. These observations warrant further investigation of these novel target proteins in platinum-resistant patients.

CD8+ Tumor-Infiltrating Lymphocyte Abundance Is a Positive Prognostic Indicator in Nasopharyngeal Cancer

PURPOSE

Tumor-infiltrating lymphocytes (TIL) are immune cell populations found within tumors, critical in the antigen-specific host immune response. In this study, we aimed to elucidate the prognostic significance of CD3+, CD4+, and CD8+ TILs in nasopharyngeal cancer (NPC).

EXPERIMENTAL DESIGN

Immune cell infiltration was quantified in NPC samples (n = 50) using RNA-sequencing (RNA-seq) data based on rearranged T-cell receptor (TCR) reads and the Estimation of Stromal and Immune cells in malignant tumors using expression data (ESTIMATE) immune score tool. The differential abundances of TIL subset populations were also characterized through IHC staining of formalin-fixed, paraffin-embedded samples from a training cohort (n = 35), which was a subset of the RNA-seq cohort (n = 50).

RESULTS

In the RNA-seq cohort, patients with higher rearranged TCR reads experienced superior 5- and 10-year overall survival (OS; P < 0.001), and disease-free survival (DFS; P < 0.001). Similarly, patients with higher ESTIMATE immune scores experienced superior 5- and 10-year OS (P = 0.024) and DFS (P = 0.007). In the training cohort, high abundances of CD8+ TILs were significantly associated with improved 5- and 10-year OS (P = 0.003) and DFS (P = 0.005). These findings were corroborated in an independent validation cohort (n = 84), and combined analysis of the training and validation cohorts [n = 119 (35+84)], which further demonstrated improved 5- and 10-year survival in terms of locoregional control (P < 0.001) and distant metastasis (P = 0.03).

CONCLUSIONS

Taken together, our study highlights the prognostic value of CD8+ TILs in NPC, and the potential of future investigations into cellular-based immunotherapies employing CD8+ lymphocytes.

TGF-β signaling in the tumor metabolic microenvironment and targeted therapies

Transforming growth factor-β (TGF-β) signaling has a paradoxical role in cancer progression, and it acts as a tumor suppressor in the early stages but a tumor promoter in the late stages of cancer. Once cancer cells are generated, TGF-β signaling is responsible for the orchestration of the immunosuppressive tumor microenvironment (TME) and supports cancer growth, invasion, metastasis, recurrence, and therapy resistance. These progressive behaviors are driven by an “engine” of the metabolic reprogramming in cancer. Recent studies have revealed that TGF-β signaling regulates cancer metabolic reprogramming and is a metabolic driver in the tumor metabolic microenvironment (TMME). Intriguingly, TGF-β ligands act as an “endocrine” cytokine and influence host metabolism. Therefore, having insight into the role of TGF-β signaling in the TMME is instrumental for acknowledging its wide range of effects and designing new cancer treatment strategies. Herein, we try to illustrate the concise definition of TMME based on the published literature. Then, we review the metabolic reprogramming in the TMME and elaborate on the contribution of TGF-β to metabolic rewiring at the cellular (intracellular), tissular (intercellular), and organismal (cancer-host) levels. Furthermore, we propose three potential applications of targeting TGF-β-dependent mechanism reprogramming, paving the way for TGF-β-related antitumor therapy from the perspective of metabolism.

Fibrotic Response of Human Trabecular Meshwork Cells to Transforming Growth Factor-Beta 3 and Autotaxin in Aqueous Humor

This study examines the potential role of transforming growth factor-beta 3 (TGF-β3) on the fibrotic response of cultured human trabecular meshwork (HTM) cells. The relationships and trans-signaling interactions between TGF-β3 and autotaxin (ATX) in HTM cells were also examined. The levels of TGF-β and ATX in the aqueous humor (AH) of patients were measured by an immunoenzymetric assay. The TGF-β3-induced expression of the fibrogenic markers, fibronectin, collagen type I alpha 1 chain, and alpha-smooth muscle actin, and ATX were examined by quantitative real-time PCR, Western blotting, and immunocytochemistry, and the trans-signaling regulatory effect of TGF-β3 on ATX expression was also evaluated. In HTM cells, the significant upregulation of ATX was induced by TGF-β3 at a concentration of 0.1 ng/mL, corresponding to the physiological concentration in the AH of patients with exfoliative glaucoma (XFG). However, higher concentrations of TGF-β3 significantly suppressed ATX expression. TGF-β3 regulated ATX transcription and signaling in HTM cells, inducing the upregulation of fibrogenic proteins in a dose-dependent manner. Trans-signaling of TGF-β3 regulated ATX transcription, protein expression, and signaling, and was thereby suggested to induce fibrosis of the trabecular meshwork. Modulation of trans-signaling between TGF-β3 and ATX may be key to elucidate the pathology of XFG, and for the development of novel treatment modalities.

Mechanistic Interrogation of Cell Transformation In Vitro: The Transformics Assay as an Exemplar of Oncotransformation

The Transformics Assay is an in vitro test which combines the BALB/c 3T3 Cell Transformation Assay (CTA) with microarray transcriptomics. It has been shown to improve upon the mechanistic understanding of the CTA, helping to identify mechanisms of action leading to chemical-induced transformation thanks to RNA extractions in specific time points along the process of in vitro transformation. In this study, the lowest transforming concentration of the carcinogenic benzo(a)pyrene (B(a)P) has been tested in order to find molecular signatures of initial events relevant for oncotransformation. Application of Enrichment Analysis (Metacore) to the analyses of the results facilitated key biological interpretations. After 72 h of exposure, as a consequence of the molecular initiating event of aryl hydrocarbon receptor (AhR) activation, there is a cascade of cellular events and microenvironment modification, and the immune and inflammatory responses are the main processes involved in cell response. Furthermore, pathways and processes related to cell cycle regulation, cytoskeletal adhesion and remodeling processes, cell differentiation and transformation were observed.

Role of high ubiquitin‑conjugating enzyme E2 expression as a prognostic factor in nasopharyngeal carcinoma

The incidence of nasopharyngeal carcinoma (NPC) in Southeast Asia and Taiwan is high due to epidemiological factors. Cisplatin-based chemoradiotherapy is an important treatment strategy with excellent outcomes for patients with NPC. However, the outcomes for patients who are refractory to cisplatin-based therapy are poor. Methods for risk stratification of patients with NPC undergoing cisplatin-based chemoradiotherapy require to be investigated. A previous study indicated that ubiquitin-conjugating enzyme E2 B (UBE2B) was able to regulate alkylating drug sensitivity in NPC cells. In the present study, the clinical significance of UBE2B expression in patients with NPC was analyzed. Analysis of the two available NPC datasets containing the UBE2B expression profile (GSE12452 and GSE68799) was performed to evaluate the UBE2B expression levels in NPC tissues compared with nasopharyngeal mucosal epithelial tissues. Furthermore, immunohistochemical staining was performed using anti-UBE2B antibodies on samples from 124 patients with NPC who underwent cisplatin-based chemoradiotherapy. Disease-specific survival (DSS), distant metastatic-free survival (DMeFS) and local recurrence-free survival (LRFS) of patients with high and low UBE2B expression was analyzed. Furthermore, the associations between UBE2B expression and the biological behavior of NPC cells were investigated in vitro. Using public NPC datasets and in vitro studies, it was identified that UBE2B expression levels were increased in NPC tumor tissues compared with those in mucosal epithelial tissues. The cell proliferation ability was decreased in UBE2B-deficient NPC cells as compared with that in UBE2B-proficient cells. Immunohistochemical analysis of 124 NPC tissues from patients who underwent cisplatin-based chemoradiotherapy indicated that high UBE2B expression levels were associated with poor DSS, DMeFS and LRFS. Multivariate regression analysis of factors influencing survival also confirmed that high UBE2B expression levels were a statistically significant independent risk factor for poor clinical outcomes in terms of DSS [hazard ratio (HR), 1.955; 95% CI 1.164-3.282], DMeFS (HR, 2.141; 95% CI 1.206-3.801) and LRFS (HR, 2.557; 95 CI 1.313-4.981). In vitro analysis indicated that O6-methylguanine-DNA methyltransferase attenuated cisplatin sensitivity induced by knockdown of UBE2B in NPC cells. In conclusion, the present study demonstrated that high UBE2B expression is associated with poor clinical outcomes for patients with NPC treated with cisplatin-based chemoradiotherapy.

MiR-766-3p Suppresses Malignant Behaviors and Stimulates Apoptosis of Colon Cancer Cells via Targeting TGFBI

BACKGROUND

MicroRNAs (miRNAs) can affect the progression of colon cancer cells. A variety of miRNAs, especially miR-766-3p, are proved to be abnormally expressed in colon cancer, but the molecular mechanism of miR-766-3p in this cancer has not yet been fully defined.

METHODS

Differentially expressed genes in the TCGA-COAD dataset were searched through bioinformatics analysis. MiR-766-3p and TGFBI mRNA levels were measured by qRT-PCR. TGFBI protein expression was measured via Western blot. Targeting relation between miR-766-3p and TGFBI was investigated by dual-luciferase reporter gene assay. Cell proliferation, invasion migration, and apoptosis were detected by cell functional assays.

RESULTS

MiR-766-3p was less expressed, while TGFBI was conspicuously highly expressed in colon cancer. MiR-766-3p high expression suppressed cell malignant behaviors and induced cell apoptosis in colon cancer. MiR-766-3p had a targeting relation with TGFBI verified by dual-luciferase assay. The cancer-suppressive impact of miR-766-3p overexpression was attenuated by overexpressing TGFBI.

CONCLUSIONS

MiR-766-3p/TGFBI axis suppressed malignant behaviors and facilitated apoptosis of colon cancer cells. MiR-766-3p may be an underlying target for colon cancer.

Pan-Cancer Analysis of the Associations of TGFBI Expression With Prognosis and Immune Characteristics

Transforming growth factor-beta-induced (TGFBI) protein has important roles in tumor growth, metastasis, and immunity. However, there is currently no pan-cancer evidence regarding TGFBI. In this study, we conducted a pan-cancer analysis of TGFBI mRNA and protein expression and prognoses of various cancer types using public databases. We also investigated the associations of TGFBI expression with tumor microenvironment (TME) components, immune cell infiltration, tumor mutational burden (TMB), and microsatellite instability (MSI), along with the TGFBI genetic alteration types. The results showed that TGFBI expression varied among different cancer types, and it was positively or negatively related to prognosis in various cancers. TGFBI expression was also significantly correlated with TME components, TMB, MSI, immune cell infiltration, and immunoinhibitory and immunostimulatory gene subsets. These findings indicate that TGFBI participates in various immune responses and it may function as a prognostic marker in various cancers. The findings may be useful for developing immunotherapies that target TGFBI.

A Five-MicroRNA Signature Predicts the Prognosis in Nasopharyngeal Carcinoma

Background

There is no effective prognostic signature that could predict the prognosis of nasopharyngeal carcinoma (NPC).

Methods

We constructed a prognostic signature based on five microRNAs using random forest and Least Absolute Shrinkage And Selection Operator (LASSO) algorithm on the GSE32960 cohort (N = 213). We verified its prognostic value using three independent external validation cohorts (GSE36682, N = 62; GSE70970, N = 246; and TCGA-HNSC, N = 523). Through principal component analysis, receiver operating characteristic curve analysis, and C-index calculation, we confirmed the predictive accuracy of this prognostic signature.

Results

We calculated the risk score based on the LASSO algorithm and divided the patients into high- and low-risk groups according to the calculated optimal cutoff value. The patients in the high-risk group tended to have a worse prognosis outcome and chemotherapy response. The time-dependent receiver operating characteristic curve showed that the 1-year overall survival rate of the five-microRNA signature had an area under the curve of more than 0.83. A functional annotation analysis of the five-microRNA signature showed that the patients in the high-risk group were usually accompanied by activation of DNA repair and MYC-target pathways, while the patients in the low-risk group had higher immune-related pathway signals.

Conclusions

We constructed a five-microRNA prognostic signature, which could accurately predict the prognosis of nasopharyngeal carcinoma, and constructed a nomogram that could conveniently predict the overall survival of patients.

Crosstalk between transforming growth factor β-2 and Autotaxin in trabecular meshwork and different subtypes of glaucoma

BACKGROUND

Elevated transforming growth factor (TGF)-β2 in aqueous humor (AH) has been suggested to contribute to trabecular meshwork (TM) fibrosis and intraocular pressure (IOP) regulation in primary open-angle glaucoma (POAG), but TGF-β2 is downregulated in secondary open-angle glaucoma (SOAG). Because autotaxin (ATX) is upregulated in SOAG, we investigated the relationships and trans-signaling interactions of these mediators.

METHODS

The level of ATX in AH was determined using a two-site immunoenzymetric assay, and TGF-β levels were measured using the Bio-Plex Pro TGF-β Assay. RNA scope was used to assess the expression of ATX and TGF-β2 in human's eye specimen. And in vitro studies were performed using hTM cells to explore if trans-signaling of TGF-β2 regulates ATX expressions.

RESULTS

TGF-β2/ATX ratio was significantly high in AH of control or POAG compared with SOAG, and negatively correlated with IOP. RNA scope revelated positive expressions of both TGF-β2 and ATX in ciliary body (CB) and TM in control, but ATX expressions was significantly enhanced in SOAG. In hTM cells, ATX expressions were regulated by TGF-β2 with concentration-dependent manner. In counter, ATX also induced TGF-β1, TGF-β2 and TGFBI upregulations and activation of the Smad-sensitive promoter, as well as upregulation of fibrotic markers, and these upregulation was significantly suppressed by both TGF-β and ATX inhibition.

CONCLUSIONS

Trans-signaling of TGF-β2 regulates ATX expressions and thereby induced upregulations of TGF-βs or fibrosis of hTM. TGF-β2 trans-signaling potently regulate ATX transcription and signaling in hTM cells, which may reflect different profile of these mediators in glaucoma subtypes. Trial Registration This prospective observational study was approved by the Institutional Review Board of the University of Tokyo and was registered with the University Hospital Medical Information Network Clinical Trials Registry of Japan (ID: UMIN000027137). All study procedures conformed to the Declaration of Helsinki. Written informed consent was obtained from each patient.

The role of the extracellular matrix protein TGFBI in cancer

The secreted extracellular protein, transforming growth factor beta induced (TGFBI or βIGH3), has roles in regulating numerous biological functions, including cell adhesion and bone formation, both during embryonic development and during the pathogenesis of human disease. TGFBI has been most studied in the context of hereditary corneal dystrophies, where mutations in TGFBI result in accumulation of TGFBI in the cornea. In cancer, early studies focused on TGFBI as a tumor suppressor, in part by promoting chemotherapy sensitivity. However, in established tumors, TGFBI largely has a role in promoting tumor progression, with elevated levels correlating to poorer clinical outcomes. As an important regulator of cancer progression, TGFBI expression and function is tightly regulated by numerous mechanisms including epigenetic silencing through promoter methylation and microRNAs. Mechanisms to target TGFBI have potential clinical utility in treating advanced cancers, while assessing TGFBI levels could be a biomarker for chemotherapy resistance and tumor progression.

Identification of Hub Genes Associated With Sensitivity of 5-Fluorouracil Based Chemotherapy for Colorectal Cancer by Integrated Bioinformatics Analysis

Colorectal cancer (CRC) is one of the most common malignant tumors. 5-fluorouracil (5-FU) has been used for the standard first-line treatment for CRC patients for several decades. Although 5-FU based chemotherapy has increased overall survival (OS) of CRC patients, the resistance of CRC to 5-FU based chemotherapy is the principal cause for treatment failure. Thus, identifying novel biomarkers to predict response to 5-FU based chemotherapy is urgently needed. In the present study, the gene expression profile of GSE3964 from the Gene Expression Omnibus database was used to explore the potential genes related to intrinsic resistance to 5-FU. A gene module containing 81 genes was found to have the highest correlation with chemotherapy response using Weighted Gene Co-expression Network Analysis (WGCNA). Then a protein-protein interaction (PPI) network was constructed and ten hub genes (TGFBI, NID, LEPREL2, COL11A1, CYR61, PCOLCE, IGFBP7, COL4A2, CSPG2, and VTN) were identified using the CytoHubba plugin of Cytoscape. Seven of these hub genes showed significant differences in expression between chemotherapy-sensitive and chemotherapy-resistant samples. The prognostic value of these seven genes was evaluated using TCGA COAD (Colorectal Adenocarcinoma) data. The results showed that TGFBI was highly expressed in chemotherapy-sensitive patients, and patients with high TGFBI expression have better survival.

LncRNAs and miRNAs participate in determination of sensitivity of cancer cells to cisplatin

Cisplatin is an extensively used chemotherapeutic substance for various types of human malignancies including sarcomas, carcinomas and lymphomas. Yet, the vast application of this drug is hampered by the emergence of chemoresistance in some treated patients. Several mechanisms such as degradation of the membrane transporters by cisplatin have been implicated in the pathogenesis of this event. Recent researches have also indicated the role of long non-coding RNAs (lncRNAs) as well as micoRNAs (miRNAs) in the emergence of resistance to cisplatin in several cancer types. For instance, up-regulation of miR-21 has been associated with resistance to this agent in ovarian cancer, oral squamous cell cancer, gastric malignancy and non-small cell lung cancer (NSCLC). On the other hand, down-regulation of miR-218 has been implicated in emergence of chemoresistance in breast cancer and esophageal squamous cell carcinoma. MALAT1 is implicated in the chemoresistance of bladder cancer cells, NSCLC, gastric cancer and cervical cancer. Most notably, the expression profile of resistance-associated miRNAs and lncRNAs can predict overall survival of cancer patients. Mechanistic assays have revealed that interference with expression of some miRNAs and lncRNAs can reverse the resistance phenotype in cancer cells. In this paper, we review the scientific writings on the role of lncRNAs and miRNAs in the evolution of chemoresistance to cisplatin in cancer cells.

LncRNA Hoxaas3 promotes lung fibroblast activation and fibrosis by targeting miR-450b-5p to regulate Runx1

Long noncoding RNAs (lncRNAs) participate in organ fibrosis and various pulmonary diseases, but its role in idiopathic pulmonary fibrosis (IPF) is not fully understood. In this study, we found lncRNA Hoxaas3 (Hoxaas3) was up-regulated in the mice model of BLM-induced PF and TGF-β1-induced fibrogenesis in lung fibroblasts (LF). Overexpression of Hoxaas3 promoted fibrogenesis, whereas Hoxaas3 inhibition attenuated lung fibrosis both in vitro and in vivo, through regulation of miR-450b-5p. Furthermore, miR-450b-5p inhibition stimulated fibrogenesis by regulating runt-related transcription factor 1 (Runx1), whereas up-regulation of miR-450b-5p alleviated fibrogenesis in LF. Mechanistically, our study showed that Hoxaas3 regulated lung fibroblast activation and fibrogenesis by acting as a competing endogenous RNA for miR-450b-5p: Hoxaas3 decreased the expression of miR-450b-5p to stimulate level and activity of Runx1 and induced fibrotic LF, whereas Runx1 inhibition alleviated the pro-fibrotic effect of Hoxaas3. In addition, Hoxaas3 was regulated by TGF-β1/Smad4 pathway as its transcriptional target. In conclusion, our study showed the role and mechanism of the TGF-β1/Smad4- Hoxaas3–miR-450b-5p–Runx1 axis for a better understanding of PF, demonstrated Hoxaas3 maybe a new diagnostic biomarker or potential therapeutic target for IPF.

Chemotherapy and chemo-resistance in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is closely associated with Epstein-Barr virus (EBV) and occurs frequently in the south of China and Southeast Asian countries. Concurrent chemo-radiotherapy is one of the main treatments for NPC. Although, the combined treatment of chemo-radiotherapy produces a satisfying survival rate, the chemo-resistance arises as a big obstacle in curing recurrent NPC patients. The acquirement of chemo-resistance is usually along with a poor prognosis. So far, the mechanism of chemo-resistance in NPC has not been fully elucidated and there have not been a comprehensive review on this issue. Thus, it is of great significance to summarize the mechanisms involved in NPC chemo-resistance. In this review, the importance and limitations of chemotherapy and the mechanisms of chemo-resistances in NPC were discussed.

MiR-34c downregulation leads to SOX4 overexpression and cisplatin resistance in nasopharyngeal carcinoma

Background

A major cause of disease-related death in nasopharyngeal carcinoma (NPC) is the development of distant metastasis (DM) despite combination chemoradiotherapy treatment. We previously identified and validated a four microRNA (miRNA) signature that is prognostic for DM. In this study, characterization of a key component of this signature, miR-34c, revealed its role in chemotherapy resistance.

Methods

Two hundred forty-six NPC patient biopsy samples were subject to comprehensive miRNA profiling and immunohistochemistry (IHC). Two human normal nasopharyngeal cell lines (immortalized; NP69 and NP460), as well as the NPC cell line C666–1, were used for miR-34c gain-of-function and loss-of-function experiments. Signaling pathways were assessed using quantitative real-time PCR (qRT-PCR) and Western blot. Cell viability was measured using the ATPlite assay.

Results

MiR-34c was downregulated in NPC patient samples, and confirmed in vitro to directly target SOX4, a master regulator of epithelial-to-mesenchymal transition (EMT). MiR-34c downregulation triggered EMT-representative changes in NP69 and NP460 whereby Snail, ZEB1, CDH2, and SOX2 were upregulated, while Claudin-1 and CDH1 were downregulated. Phenotypically, inhibition of miR-34c led to cisplatin resistance, whereas miR-34c over-expression sensitized NPC cells to cisplatin. TGFβ1 decreased miR-34c and increased SOX4 expression in vitro. The TGFβ receptor 1 inhibitor SB431542 reduced SOX4 expression and increased cisplatin sensitivity. Finally, IHC revealed that lower SOX4 expression was associated with improved overall survival in chemotherapy-treated NPC patients.

Conclusion

miR-34c is downregulated in NPC. Repression of miR-34c was shown to increase SOX4 expression, which leads to cisplatin resistance, while TGFβ1 was found to repress miR-34c expression. Taken together, our study demonstrates that inhibition of the TGFβ1 pathway could be a strategy to restore cisplatin sensitivity in NPC.

Effect of BRCA1 on the Concurrent Chemoradiotherapy Resistance of Cervical Squamous Cell Carcinoma Based on Transcriptome Sequencing Analysis

Background

Cervical squamous cell carcinoma (CSCC) is the main pathological type of cervical cancer, accounting for 80%–85% of cervical cancer. Owing to concurrent chemoradiotherapy (CCRT) resistance in a subset of CSCC patients, the treatment response is often unsatisfactory. Identifying predictors and therapeutic targets related to cisplatin-based CCRT resistance in CSCC is critical.

Methods

We reanalyzed GSE56363, an mRNA dataset from the GEO database with 21 patients with locally advanced CSCC, to identify differentially expressed genes (DEGs) related to CCRT resistance. The hub genes were screened from the protein-protein interaction network of DEGs using cytoHubba plug-in of Cytoscape software. Transcriptome sequencing technology was used to compare differential expression between SiHa cells overexpressing BRCA1 compared with control SiHa cells. Functional annotation for DEGs and gene set enrichment analysis (GSEA) was performed to identify DEG-enriched relative signaling pathways to examine the molecular mechanisms of BRCA1 in CCRT resistance of CSCC. qPCR was used to verify the expression of key genes in SiHa/DDP cells.

Results

A total of 609 DEGs including 223 upregulated DEGs and 386 downregulated DEGs were identified between the complete response to CCRT (CR) and noncomplete response to CCRT (NCR) CSCC patients based on the GSE56363 dataset. Ten hub genes with the highest degrees were identified via the plug-in CytoHubba in Cytoscape: BRCA1, CDCA8, ASPM, CDC45, RAD51, HMMR, CENPF, EXO1, DTL, and ZWINT genes, and BRCA1 ranked first. Through transcriptome sequencing analysis based on GSE141558, 1344 DEGs were identified in BRCA1-overexpressing SiHa cells, including 824 upregulated DEGs and 520 downregulated DEGs. GSEA results showed that CCRT-resistance related signaling pathways, such as the JAK/STAT signaling pathway and the WNT signaling pathway, were differentially enriched in BRCA1-expressing SiHa cells. STAT1, STAT2, and CCND1 were screened as the differentially expressed target genes of BRCA1 and may correlate with resistance of CSCC. qPCR results showed that only STAT1 was significantly increased in SiHa cells with GV230-BRCA1 plasmid transfection.

Conclusion

BRCA1 overexpression in SiHa cells may upregulate STAT1 to activate the JAK/STAT signaling pathway, suggesting a mechanism for enhanced CCRT resistance.

miR-1278 sensitizes nasopharyngeal carcinoma cells to cisplatin and suppresses autophagy via targeting ATG2B

Chemoresistance to cisplatin (DDP) has become a dominating obstacle to the successful treatment of nasopharyngeal carcinoma (NPC). Recently, accumulating data support the tenet that microRNAs (miRNAs) function as new crucial regulators of diverse biological processes, including chemoresistance. In this study, the miRNA expression profiles in NPC were first analyzed using miRNA microarray dataset. miR-1278 was identified as the most decreased miRNA in NPC tissues. We then validated that miR-1278 was significantly down-regulated in NPC tissues and cell lines. Moreover, decreased miR-1278 was strongly associated with worse overall survival and poor chemotherapy response. Gain-of-function experiments showed that overexpression of miR-1278 dramatically sensitized NPC cells to DDP and reduced autophagy. Mechanistically, ATG2B was identified as a target gene of miR-1278. More importantly, ATG2B overexpression reversed miR-1278-induced suppression of autophagy and DDP resistance. Taken together, our results suggested that miR-1278 inhibited the DDP resistance of NPC cells and autophagy through targeting ATG2B. miR-1278 might function as a novel therapeutic target in NPC treatment.

Regulatory effect of hsa-miR-5590-3P on TGFβ signaling through targeting of TGFβ-R1, TGFβ-R2, SMAD3 and SMAD4 transcripts

Transforming growth factor-β (TGFβ) signaling acts as suppressor and inducer of tumor progression during the early and late stages of cancer, respectively. Some miRNAs have shown a regulatory effect on TGFβ signaling and here, we have used a combination of bioinformatics and experimental tools to show that hsa-miR-5590-3p is a regulator of multiple genes expression in the TGFβ signaling pathway. Consistent with the bioinformatics predictions, hsa-miR-5590-3p had a negative correlation of expression with TGFβ-R1, TGFβ-R2, SMAD3 and SMAD4 genes, detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Then, the dual luciferase assay supported the direct interaction between hsa-miR-5590-3p and TGFβ-R1, TGFβ-R2, SMAD3 and SMAD4-3'UTR sequences. Consistently, the TGFβ-R1 protein level was reduced following the overexpression of hsa-miR-5590-3p, detected by Western analysis. Also, hsa-miR-5590-3p overexpression brought about the downregulation of TGFβ-R1, TGFβ-R2, SMAD3 and SMAD4 expression in HCT-116 cells, detected by RT-qPCR, followed by cell cycle arrest in the sub-G1 phase, detected by flow cytometry. RT-qPCR results indicated that hsa-miR-5590-3p is significantly downregulated in breast tumor tissues (late stage) compared to their normal pairs. Altogether, data introduces hsa-miR-5590-3p as a negative regulator of the TGFβ/SMAD signaling pathway which acts through downregulation of TGFβ-R1, TGFβ-R2, SMAD3 and SMAD4 transcripts. Therefore, it can be tested as a therapy target in cancers in which the TGFβ/SMAD pathway is deregulated.

RIG-I promotes IFN/JAK2 expression and the endoplasmic reticulum stress response to inhibit chemoradiation resistance in nasopharyngeal carcinoma

RIG-I is associated with the occurrence and development of many tumors. However, the role of RIG-I in radiotherapy and chemotherapy in NPC has not been reported to date. In our study, RIG-I expression was significantly reduced in chemoradiotherapy-resistant NPC tissues and cells compared with that in therapy-sensitive tissues and cells. RIG-I expression increased in nonresistant NPC cells, including CNE1 and CNE2, in a dose-dependent manner with increasing chemotherapy drug concentration or radiotherapy dose. RIG-I overexpression promoted radiotherapy and chemotherapy sensitivity in NPC cells, leading to cellular apoptosis and increased expression of the proapoptotic factors BAX and caspase-3. Similarly, RIG-I knockdown in NPC cells promoted chemoradiotherapy resistance and reduced apoptosis. Analysis of microarray data indicated that the expression of IFN/JAK2 and endoplasmic reticulum (ER) stress response markers, such as JAK2, STAT1, IRF9, IFNB1, IRF3, p-IRF3, XBP1, ATF6, IFIT2, and ISG15, was inhibited in chemoradiotherapy-resistant cells compared with that in sensitive cells. Conversely, activation of IFN/JAK2 and ER stress response pathways in NPC cells reduced paclitaxel resistance and increased apoptosis. RIG-I promotes IFN/JAK2 and ER stress response-mediated apoptosis to inhibit chemoradiation resistance in nasopharyngeal carcinoma.

Skp2-mediated ubiquitination and mitochondrial localization of Akt drive tumor growth and chemoresistance to cisplatin

The E3 ligase S-phase kinase-associated protein 2(Skp2) is overexpressed in human cancers and correlated with poor prognosis, but its contributions to tumorigenesis and chemoresistance in nasopharyngeal carcinoma (NPC) are not evident. Herein we show that Skp2 is highly expressed in NPC tumor tissues and cell lines. Knockdown of Skp2 suppresses tumor cell growth, colony formation, glycolysis, and in vivo tumor growth. Skp2 promotes Akt K63-mediated ubiquitination and activation, which is required for EGF-induced Akt mitochondrial localization. Importantly, K63-linked ubiquitination enhances the interaction between Akt and HK2 and eventually increases HK2 phosphorylation on Thr473 and mitochondrial localization. Overexpression of Skp2 impaired the intrinsic apoptotic pathway and confers cisplatin resistance. Moreover, ectopic expression of Myr-Akt1 or phosphomimetic HK2-T473D rescued cisplatin-induced tumor suppression in Skp2 knockdown stable cells. Also, depletion of Akt ubiquitination enhances the antitumor efficacy of cisplatin in vitro and in vivo. Finally, we demonstrated that Skp2 is positively correlated with p-Akt and HK2 in NPC tumor tissues. This study highlights the clinical value of Skp2 targeting in NPC treatment.

Feedback loop in miR-449b-3p/ADAM17/NF-κB promotes metastasis in nasopharyngeal carcinoma

An emerging body of evidence has promoted the understanding of the role of microRNAs (miRNAs) in tumorigenesis and progression, but the mediating function of miRNAs in nasopharyngeal carcinoma (NPC) development remains poorly elucidated. In this study, miR‐449b‐3p was downregulated in NPC specimens (P < .001) and cells (P < .05). Cytological and animal experiments provided evidence that miR‐449b‐3p inhibited NPC metastasis in vitro and in vivo. Disintegrin and metalloproteinase 17 (ADAM17) was revealed as a direct target of miR‐449b‐3p. Rescue experiments suggested that the downregulation of ADAM17 in the miR‐449b‐3p knockdown cells partially reversed the inhibition of cell invasion and migration. Luciferase reporter assay, chromatin immunoprecipitation assay, and Western blot analysis showed that ADAM17 could suppress the promoter activity and expression of miR‐449b‐3p by inducing NF‐κB transcriptional activity. In conclusion, our study provided new insights into the underlying mechanism of the invasion and metastasis of NPC. The novel miR‐449b‐3p/ADAM17/NF‐κB feedback loop could be a target for the clinical treatment of NPC.

Secreted TGF-beta-induced protein promotes aggressive progression in bladder cancer cells

Background: Transforming growth factor-beta-induced (TGFBI) is an exocrine protein, which has been found to be able to promote the development of nasopharyngeal carcinoma, glioma, pancreatic cancer, and other tumors. However, there is currently no report concerning the relationship between TGFBI and invasive progression of bladder cancer (BCa).

Methods: IHC staining, qRT-PCR and Western blot were used to analyze TGFBI and EMT markers levels. In vivo tumorigenesis was performed by xenograft tumor model.

Results: In this study, we found that both mRNA and protein levels of TGFBI were significantly up-regulated in muscle invasive bladder cancer (MIBC) tissues compared with non-muscle-invasive bladder cancer (NMIBC) tissues. The high expression level of TGFBI was positively correlated with high histological grade and advanced clinical stage, and BCa patients with high TGFBI levels exhibited poor prognoses. We further confirmed that high expression level of TGFBI can promote proliferation, invasive progression, and epithelial-to-mesenchymal transition (EMT) of BCa cells in vitro, as well as promote tumor growth and EMT in vivo, while silencing of TGFBI inhibited these malignant phenotypes. TGFBI was involved in the up-regulation of EMT by inducing the expression level of Slug, Vimentin, Snail, MMP2, and MMP9 genes, while it down-regulated the expression level of E-cadherin. Moreover, Western blot analysis was carried out to demonstrate that BCa cell lines stably transfected with expression of TGFBI, a secreted protein. Furthermore, conditional medium containing TGFBI protein also resulted in enhanced EMT and malignant phenotype of BCa cells.

Conclusion: Our results indicate that high expression level of TGFBI promotes EMT, proliferation, and invasive progression of BCa cells, and TGFBI is a potential therapeutic target and prognostic marker for BCa.

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Epigenetic silencing of TGFBI confers resistance to trastuzumab in human breast cancer

Background

Acquired resistance to trastuzumab is a major clinical problem in the treatment of HER2-positive (HER2+) breast cancer patients. The selection of trastuzumab-resistant patients is a great challenge of precision oncology. The aim of this study was to identify novel epigenetic biomarkers associated to trastuzumab resistance in HER2+ BC patients.

Methods

We performed a genome-wide DNA methylation (450K array) and a transcriptomic analysis (RNA-Seq) comparing trastuzumab-sensitive (SK) and trastuzumab-resistant (SKTR) HER2+ human breast cancer cell models. The methylation and expression levels of candidate genes were validated by bisulfite pyrosequencing and qRT-PCR, respectively. Functional assays were conducted in the SK and SKTR models by gene silencing and overexpression. Methylation analysis in 24 HER2+ human BC samples with complete response or non-response to trastuzumab-based treatment was conducted by bisulfite pyrosequencing.

Results

Epigenomic and transcriptomic analysis revealed the consistent hypermethylation and downregulation of TGFBI, CXCL2, and SLC38A1 genes in association with trastuzumab resistance. The DNA methylation and expression levels of these genes were validated in both sensitive and resistant models analyzed. Of the genes, TGFBI presented the highest hypermethylation-associated silencing both at the transcriptional and protein level. Ectopic expression of TGFBI in the SKTR model suggest an increased sensitivity to trastuzumab treatment. In primary tumors, TGFBI hypermethylation was significantly associated with trastuzumab resistance in HER2+ breast cancer patients.

Conclusions

Our results suggest for the first time an association between the epigenetic silencing of TGFBI by DNA methylation and trastuzumab resistance in HER2+ cell models. These results provide the basis for further clinical studies to validate the hypermethylation of TGFBI promoter as a biomarker of trastuzumab resistance in HER2+ breast cancer patients.

Electronic supplementary material

The online version of this article (10.1186/s13058-019-1160-x) contains supplementary material, which is available to authorized users.

Interference of the long noncoding RNA CDKN2B-AS1 upregulates miR-181a-5p/TGFβI axis to restrain the metastasis and promote apoptosis and senescence of cervical cancer cells

Long noncoding RNA (lncRNA) CDKN2B-AS1 has been shown to play a crucial role in the development as well as in the prognosis of various human cancers, including cervical cancer. However, the underlying mechanisms need to be further explored between CDKN2B-AS1 and cervical cancer. In the present study, RT-PCR showed that the mRNA level of CDKN2B-AS1 was significantly upregulated while the miR-181a-5p was downregulated in cervical cancer cell lines. In addition, the interference of CDKN2B-AS1 by shRNA resulted in the suppression of cell proliferation, invasion, migration and promotion of apoptosis and senescence, and either CDKN2B-AS1 overexpression or miR-181a-5p showed reversed results. Further studies demonstrated that CDKN2B-AS1 could directly interact with miR-181a-5p, and that there was an inverse correlation between miR-181a-5p and CDKN2B-AS1. In addition, we found that TGFβI was a target of miR-181a-5p and could be downregulated by CDKN2B-AS1 knockdown. Moreover, the in vivo experiments further demonstrated the contribution of CDKN2B-AS1 in cervical cancer including tumor growth, apoptosis inhibition and senescence inhibition, and CDKN2B-AS1 knockdown could inhibit the aforementioned activities. In summary, our study demonstrated that the CDKN2B-AS1/miR-181a-5p/TGFβI axis might play a vital role in cervical cancer development.

Characterisation of an Isogenic Model of Cisplatin Resistance in Oesophageal Adenocarcinoma Cells

Cisplatin (cis-diamminedichloroplatinum) is widely used for the treatment of solid malignancies; however, the development of chemoresistance hinders the success of this chemotherapeutic in the clinic. This study provides novel insights into the molecular and phenotypic changes in an isogenic oesophageal adenocarcinoma (OAC) model of acquired cisplatin resistance. Key differences that could be targeted to overcome cisplatin resistance are highlighted. We characterise the differences in treatment sensitivity, gene expression, inflammatory protein secretions, and metabolic rate in an isogenic cell culture model of acquired cisplatin resistance in OAC. Cisplatin-resistant cells (OE33 Cis R) were significantly more sensitive to other cytotoxic modalities, such as 2 Gy radiation (p = 0.0055) and 5-fluorouracil (5-FU) (p = 0.0032) treatment than parental cisplatin-sensitive cells (OE33 Cis P). Gene expression profiling identified differences at the gene level between cisplatin-sensitive and cisplatin-resistant cells, uncovering 692 genes that were significantly altered between OE33 Cis R cells and OE33 Cis P cells. OAC is an inflammatory-driven cancer, and inflammatory secretome profiling identified 18 proteins secreted at significantly altered levels in OE33 Cis R cells compared to OE33 Cis P cells. IL-7 was the only cytokine to be secreted at a significantly higher levels from OE33 Cis R cells compared to OE33 Cis P cells. Additionally, we profiled the metabolic phenotype of OE33 Cis P and OE33 Cis R cells under normoxic and hypoxic conditions. The oxygen consumption rate, as a measure of oxidative phosphorylation, is significantly higher in OE33 Cis R cells under normoxic conditions. In contrast, under hypoxic conditions of 0.5% O₂, the oxygen consumption rate is significantly lower in OE33 Cis R cells than OE33 Cis P cells. This study provides novel insights into the molecular and phenotypic changes in an isogenic OAC model of acquired cisplatin resistance, and highlights therapeutic targets to overcome cisplatin resistance in OAC.

The Dynamic Roles of TGF-β Signalling in EBV-Associated Cancers

The transforming growth factor-β (TGF-β) signalling pathway plays a critical role in carcinogenesis. It has a biphasic action by initially suppressing tumorigenesis but promoting tumour progression in the later stages of disease. Consequently, the functional outcome of TGF-β signalling is strongly context-dependent and is influenced by various factors including cell, tissue and cancer type. Disruption of this pathway can be caused by various means, including genetic and environmental factors. A number of human viruses have been shown to modulate TGF-β signalling during tumorigenesis. In this review, we describe how this pathway is perturbed in Epstein-Barr virus (EBV)-associated cancers and how EBV interferes with TGF-β signal transduction. The role of TGF-β in regulating the EBV life cycle in tumour cells is also discussed.