TCOF1 upregulation in triple-negative breast cancer promotes stemness and tumour growth and correlates with poor prognosis.

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with poor prognosis. By performing multiomic profiling, we recently uncovered super-enhancer heterogeneity between breast cancer subtypes. Our data also revealed TCOF1 as a putative TNBC-specific super-enhancer-regulated gene. TCOF1 plays a critical role in craniofacial development but its function in cancer remains unclear. METHODS: Overall survival and multivariant Cox regression analyses were conducted using the METABRIC data set. The effect of TCOF1 knockout on TNBC growth and stemness was evaluated by in vitro and in vivo assays. RNA-seq and rescue experiments were performed to explore the underlying mechanisms. RESULTS: TCOF1 is frequently upregulated in TNBC and its elevated expression correlates with shorter overall survival. TCOF1 depletion significantly inhibits the growth and stemness of basal-like TNBC, but not of mesenchymal-like cells, highlighting the distinct molecular dependency in different TNBC subgroups. RNA-seq uncovers several stem cell molecules regulated by TCOF1. We further demonstrate that KIT is a downstream effector of TCOF1 in mediating TNBC stemness. TCOF1 expression in TNBC is regulated by the predicted super-enhancer. CONCLUSIONS: TCOF1 depletion potently attenuates the growth and stemness of basal-like TNBC. Expression of TCOF1 may serve as a TNBC prognostic marker and a therapeutic target.

Discovering long noncoding RNA predictors of anticancer drug sensitivity beyond protein-coding genes.

Large-scale cancer cell line screens have identified thousands of protein-coding genes (PCGs) as biomarkers of anticancer drug response. However, systematic evaluation of long noncoding RNAs (lncRNAs) as pharmacogenomic biomarkers has so far proven challenging. Here, we study the contribution of lncRNAs as drug response predictors beyond spurious associations driven by correlations with proximal PCGs, tissue lineage, or established biomarkers. We show that, as a whole, the lncRNA transcriptome is equally potent as the PCG transcriptome at predicting response to hundreds of anticancer drugs. Analysis of individual lncRNAs transcripts associated with drug response reveals nearly half of the significant associations are in fact attributable to proximal cis-PCGs. However, adjusting for effects of cis-PCGs revealed significant lncRNAs that augment drug response predictions for most drugs, including those with well-established clinical biomarkers. In addition, we identify lncRNA-specific somatic alterations associated with drug response by adopting a statistical approach to determine lncRNAs carrying somatic mutations that undergo positive selection in cancer cells. Lastly, we experimentally demonstrate that 2 lncRNAs, EGFR-AS1 and MIR205HG, are functionally relevant predictors of anti-epidermal growth factor receptor (EGFR) drug response.

Lithium from breast-milk inhibits thyroid iodine uptake and hormone production, which are remedied by maternal iodine supplementation.

BACKGROUND: Lithium is especially taken as a maintenance medication for Bipolar Disorder. In women with bipolar disorder, lithium is often effective during postpartum period, but breast-feeding for medicated mothers is controversial because of harmful effects for her child. At present, the biological mechanisms of lithium are not well-understood, affecting its usage and overall health implications. PROCEDURE: We developed a rat lithium and breast-feeding model at human therapeutic levels to study the effects of lithium exposure through breast-milk on pups' thyroid function. Novel laser analytical spectroscopy, along with traditional blood and immunohistochemical tests, were applied to further investigate the mechanisms behind the thyroid dysfunction. Maternal iodine supplementation was evaluated as a therapeutic method to address the pups' thyroid dysfunction. RESULTS: Pups exposed to lithium via breastmilk, even with the dam on a sub-therapeutic level, experienced weight gain, reduced blood thyroxine (T4 ), and elevated blood urea nitrogen, indicating effects on thyroid and kidney function. We show that lithium inhibited iodine uptake by thyroid follicles, initiating a mechanism that reduced iodination of tyrosine, thyroglobulin cleavage, and thyroid hormone production. Importantly, infant thyroid function can be significantly improved by administering supplementary iodine to the medicated dam's diet during breast-feeding. CONCLUSION: These results elucidate the mechanisms of lithium in thyroid function, provide valuable information on use postpartum, and suggest a clinically applicable remedy to side-effects. The results are particularly important for patients (and their infants) who respond well to lithium and need, or choose, to breast-feed.

Extracellular Vesicles: Biology and Potentials in Cancer Therapeutics.

Background [...].

Effect of public hospital managers' risk and gain perception on their attitude towards physician dual practice: a cross-national study in 31 provinces of China.

BACKGROUND: This study aims to explore the effect of public hospital managers' risk and gain perception on their attitude towards physician dual practice (PDP). METHODS: A cross-sectional study enrolling 1513 managers from public hospitals in the East, Middle and West of China was conducted. Generalized linear mixed models (GLMM) were used to identify the determinants of managers' support for PDP. RESULTS: The rate of managers' support for allowing PDP or implementing PDP with restriction, was 94.3% (95% CI: 0.93, 0.95). The mean score of managers' risk perception was 67.7 ± 14.46, and the mean score of managers' gain perception was 24.0 ± 5.56. After controlling for individual and institutional characteristics, the GLMM presented the score for risk perception increased 1 score and the rate of managers' support for PDP decreased by 5% (OR = 0.95, 95% CI: 0.93, 0.97); while the score for gain perception increased 1 score and the rate of managers' support increased by 18% (OR = 1.18, 95% CI: 1.12, 1.24). CONCLUSIONS: Our data demonstrate that the majority of Chinese public hospital managers are in favor of allowing or implementing PDP with restrictions. Although gain perception is comparatively weaker than risk perception, a stronger influence in determining public hospital managers' support for PDP is demonstrated.

Molecular subtyping of nasopharyngeal carcinoma (NPC) and a microRNA-based prognostic model for distant metastasis.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a highly invasive and metastatic cancer, with diverse molecular characteristics and clinical outcomes. This study aims to dissect the molecular heterogeneity of NPC, followed by the construction of a microRNA (miRNA)-based prognostic model for prediction of distant metastasis. METHODS: We retrieved two NPC datasets: GSE32960 and GSE70970 as training and validation cohorts, respectively. Consensus clustering was employed for cluster discovery, and support vector machine was used to build a classifier. Finally, Cox regression analysis was applied to constructing a prognostic model for predicting risk of distant metastasis. RESULTS: Three NPC subtypes (immunogenic, classical and mesenchymal) were identified that are molecularly distinct and clinically relevant, of which mesenchymal subtype (~ 36%) is associated with poor prognosis, characterized by suppressing tumor suppressor miRNAs and the activation of epithelial--mesenchymal transition. Out of the 25 most differentially expressed miRNAs in mesenchymal subtype, miR-142, miR-26a, miR-141 and let-7i have significant prognostic power (P < 0.05). CONCLUSIONS: We proposed for the first time that NPC can be stratified into three subtypes. Using a panel of 4 miRNAs, we established a prognostic model that can robustly stratify NPC patients into high- and low- risk groups of distant metastasis.

Application of proteomics in non-small-cell lung cancer.

Non-small-cell lung cancer (NSCLC) is a heterogeneous disease with diverse pathological features. Clinical proteomics allows the discovery of molecular markers and new therapeutic targets for this most prevalent type of lung cancer. Some of them may be used to detect early lung cancer, while others may serve as predictive markers of resistance to different therapies. Therapeutic targets and prognostic markers in NSCLC have also been discovered. These proteomics biomarkers may help to pair the individual NSCLC patient with the best treatment option. Despite the fact that implementation of these biomarkers in the clinic appears to be scarce, the recently launched Precision Medicine Initiative may encourage their translation into clinical practice.

Implications of MicroRNAs in the Treatment of Gefitinib-Resistant Non-Small Cell Lung Cancer.

Non-small cell lung cancer (NSCLC) represents about 85% of the reported cases of lung cancer. Acquired resistance to targeted therapy with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib, is not uncommon. It is thus vital to explore novel strategies to restore sensitivity to gefitinib. Provided that microRNAs (miRNAs) negatively regulate their gene targets at the transcriptional level, it is speculated that miRNA mimetics may reduce the expression, activity and signal transduction of EGFR so that sensitization of tumour sites to gefitinib-induced cytotoxicity can be achieved. Indeed, a growing body of evidence has shown that the manipulation of endogenous levels of miRNA not only attenuates the EGFR/PI3K/Akt phosphorylation cascade, but also restores apoptotic cell death in in vitro models of experimentally-induced gefitinib resistance and provoked tumour regression/shrinkage in xenograft models. These data are in concordant with the clinical data showing that the differential expression profiles of miRNA in tumour tissues and blood associate strongly with drug response and overall survival. Furthermore, another line of studies indicate that the chemopreventive effects of a variety of natural compounds may involve miRNAs. The present review aims to discuss the therapeutic capacity of miRNAs in relation to recent discoveries on EGFR-TKI resistance, including chronic drug exposure and mutations.

Exploring microRNA-mediated alteration of EGFR signaling pathway in non-small cell lung cancer using an mRNA:miRNA regression model supported by target prediction databases.

EGFR signaling pathway and microRNAs (miRNAs) are two important factors for development and treatment in non-small cell lung cancer (NSCLC). Microarray analysis enables the genome-wide expression profiling. However, the information from microarray data may not be fully deciphered through the existing approaches. In this study we present an mRNA:miRNA stepwise regression model supported by miRNA target prediction databases. This model is applied to explore the roles of miRNAs in the EGFR signaling pathway. The results show that miR-145 is positively associated with epidermal growth factor (EGF) in the pre-surgery NSCLC group and miR-199a-5p is positively associated with EGF in the post-surgery NSCLC group. Surprisingly, miR-495 is positively associated with protein tyrosine kinase 2 (PTK2) in both groups. The coefficient of determination (R(2)) and leave-one-out cross-validation (LOOCV) demonstrate good performance of our regression model, indicating that it can identify the miRNA roles as oncomirs and tumor suppressor mirs in NSCLC.

TGFßR2 is a major target of miR-93 in nasopharyngeal carcinoma aggressiveness.

BACKGROUND: MiR-17-92 cluster and its paralogues have emerged as crucial regulators of many oncogenes and tumor suppressors. Transforming growth factor-ß receptor II (TGFßR2), as an important tumor suppressor, is involved in various cancer types. However, it is in cancer that only two miRNAs of this cluster and its paralogues have been reported so far to regulate TGFßR2. MiR-93 is oncogenic, but its targetome in cancer has not been fully defined. The role of miR-93 in nasopharyngeal carcinoma (NPC) still remains largely unknown. METHODS: We firstly evaluated the clinical signature of TGFßR2 down-regulation in clinical samples, and next used a miRNA expression profiling analysis followed by multi-validations, including Luciferase reporter assay, to identify miRNAs targeting TGFßR2 in NPC. In vitro and in vivo studies were performed to further investigate the effects of miRNA-mediated TGFßR2 down-regulation on NPC aggressiveness. Finally, mechanism studies were conducted to explore the associated pathway and genes influenced by this miRNA-mediated TGFßR2 down-regulation. RESULTS: TGFßR2 was down-regulated in more than 50% of NPC patients. It is an unfavorable prognosis factor contributing to clinical NPC aggressiveness. A cluster set of 4 TGFßR2-associated miRNAs was identified; they are all from miR-17-92 cluster and its paralogues, of which miR-93 was one of the most significant miRNAs, directly targeting TGFßR2, promoting cell proliferation, invasion and metastasis in vitro and in vivo. Moreover, miR-93 resulted in the attenuation of Smad-dependent TGF-ß signaling and the activation of PI3K/Akt pathway by suppressing TGFßR2, further promoting NPC cell uncontrolled growth, invasion, metastasis and EMT-like process. Impressively, the knockdown of TGFßR2 by siRNA displayed a consentaneous phenocopy with the effect of miR-93 in NPC cells, supporting TGFßR2 is a major target of miR-93. Our findings were also substantiated by investigation of the clinical signatures of miR-93 and TGFßR2 in NPC. CONCLUSION: The present study reports an involvement of miR-93-mediated TGFßR2 down-regulation in NPC aggressiveness, thus giving extended insights into molecular mechanisms underlying cancer aggressiveness. Approaches aimed at blocking miR-93 may serve as a promising therapeutic strategy for treating NPC patients.

A four-miRNA signature identified from genome-wide serum miRNA profiling predicts survival in patients with nasopharyngeal carcinoma.

Recent findings have reported that human serum microRNAs (miRNAs) can be used as prognostic biomarkers in various cancers. We aimed to explore the prognostic value of serum miRNAs in nasopharyngeal carcinoma (NPC) patients. The level of serum miRNA was retrospectively analyzed in 512 NPC patients recruited between January 2001 and December 2006. In the discovery stage, a microarray followed by reverse transcription-quantitative polymerase chain reaction was used to identify differentially altered miRNAs in eight patients with shorter survival and eight patients with longer survival who were well matched by age, sex and clinical stage. The identified serum miRNAs were then validated in all 512 samples, which were randomly divided into a training set and a validation set. Four serum miRNAs (miR-22, miR-572, miR-638 and miR-1234) were found to be differentially altered and were used to construct a miRNA signature. Risk scores were calculated to classify the patients into high- or low-risk groups. Patients with high-risk scores had poorer overall survival [hazard ratio (HR), 2.54; 95% confidence interval (CI), 1.57-4.12; p < 0.001] and distant metastasis-free survival (HR, 3.28; 95% CI, 1.82-5.94; p < 0.001) than those with low-risk scores in the training set; these results were confirmed in the validation and combined sets. The miRNA signature and TNM stage were independent prognostic factors. The combination of the miRNA signature and TNM stage had a better prognostic value than the TNM stage or miRNA signature alone. The four-serum miRNA signature may add prognostic value to the TNM staging system and provide information for personalized therapy in NPC.

Proteomics in translational cancer research: biomarker discovery for clinical applications.

This special focus issue of Expert Review of Proteomics invites key opinion leaders to report their recent findings and views on the important topic of translating potential proteomic biomarkers to clinically useful, regulator-approved biomarkers: a challenging journey. The issue also highlights the difficulties associated with and the way forward in the discovery of proteomic cancer biomarkers for clinical applications, as well as presenting recent original research in the field.

Putative biomarkers and therapeutic targets associated with radiation resistance.

Radiation therapy plays an important role in the management of malignant tumors, however, the problem of radiation resistance resulting in tumor recurrences after treatment is still unsolved. The emergence of novel biomarkers to predict cancer cell insensitivity to ionizing radiation could help to improve therapy results in cancer patients receiving radiation therapy. The proteomic approach could be effectively used to identify proteins associated with cancer radiation resistance. It is generally believed that radiation resistance could be associated with cancer stem cell persistence within the tumor. Therefore, determination of the molecular characteristics of cancer stem cells could provide additional possibilities to discover novel biomarkers to predict radiation resistance in cancer patients. This review addresses proteome-based findings that could be used for further biomarker identification and preclinical and clinical validation.

Biomarker discovery of nasopharyngeal carcinoma by proteomics.

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors in southern China and southern Asia, and poses one of the most serious public health problems in these areas. Early diagnosis, predicting metastasis, recurrence, prognosis and therapeutic response of NPC remain a challenge. Discovery of diagnostic and predictive biomarkers is an ideal way to achieve these objectives. Proteomics has great potential in identifying cancer biomarkers. Comparative proteomics has identified a large number of potential biomarkers associated with NPC, although the clinical performance of such biomarkers needs to be further validated. In this article, we review the latest discovery and progress of biomarkers for early diagnosis, predicting metastasis, recurrence, prognosis and therapeutic response of NPC, inform the readers of the current status of proteomics-based NPC biomarker findings and suggest avenues for future work.

Towards developing biomarkers for glioblastoma multiforme: a proteomics view.

Glioblastoma multiforme (GBM) is one of the most aggressive and lethal forms of the primary brain tumors. With predominance of tumor heterogeneity and emergence of new subtypes, new approaches are needed to develop tissue-based markers for tumor typing or circulatory markers to serve as blood-based assays. Multi-omics data integration for GBM tissues would offer new insights on the molecular view of GBM pathogenesis useful to identify biomarker panels. On the other hand, mapping differentially expressed tissue proteins for their secretory potential through bioinformatics analysis or analysis of the tumor cell secretome or tumor exosomes would enhance our understanding of the tumor microenvironment and prospects for targeting circulatory biomarkers. In this review, the authors first present potential biomarker candidates for GBM that have been reported and then focus on plausible pipelines for multi-omic data integration to identify additional, high-confidence molecular panels for clinical applications in GBM.

Colorectal cancer biomarker discovery and validation using LC-MS/MS-based proteomics in blood: truth or dare?

Globally, colorectal cancer (CRC) is the third most common malignant neoplasm. However, highly sensitive, specific, noninvasive tests that allow CRC diagnosis at an early stage are still needed. As circulatory blood reflects the physiological status of an individual and/or the disease status for several disorders, efforts have been undertaken to identify candidate diagnostic CRC markers in plasma and serum. In this review, the challenges, bottlenecks and promising properties of mass spectrometry (MS)-based proteomics in blood are discussed. More specifically, important aspects in clinical design, sample retrieval, sample preparation, and MS analysis are presented. The recent developments in targeted MS approaches in plasma or serum are highlighted as well.

Stratification of clear cell renal cell carcinoma by signaling pathway analysis.

Investigation of cell signaling pathways in 16 clear cell renal cell carcinomas to identify groups based on commonly shared phosphorylation-driven signaling networks. Using laser capture microdissection and reverse-phase protein arrays, we profiled 75 key nodes spanning signaling pathways important in tumorigenesis. Analysis revealed significantly different (P < 0.05) signaling levels for 27 nodes between two groups of samples, designated A (4 samples; high EGFR, RET, and RASGFR1 levels, converging to activate AKT/mTOR) and B (12 samples; high ERK1/2 and STAT phosphorylation). Group B was further partitioned into groups C (7 samples; elevated expression of LC3B) and D (5 samples; activation of Src and STAT). Network analysis indicated that group A was characterized by signaling pathways related to cell cycle and proliferation, and group B by pathways related to cell death and survival. Homogeneous clear cell renal cell carcinomas could be stratified into at least two major functional groups.

Lectin approaches for glycoproteomics in FDA-approved cancer biomarkers.

The nine FDA-approved protein biomarkers for the diagnosis and management of cancer are approaching maturity, but their different glycosylation compositions relevant to early diagnosis still remain practically unexplored at the sub-glycoproteome scale. Lectins generally exhibit strong binding to specific sub-glycoproteome components and this property has been quite poorly addressed as the basis for the early diagnosis methods. Here, we discuss some glycoproteome issues that make tackling the glycoproteome particularly challenging in the cancer biomarkers field and include a brief view for next generation technologies.

MicroRNAs Involved in Anti-Tumour Immunity.

MicroRNAs (miRNAs) are a category of small RNAs that constitute a new layer of complexity to gene regulation within the cell, which has provided new perspectives in understanding cancer biology. The deregulation of miRNAs contributes critically to the development and pathophysiology of a number of cancers. miRNAs have been found to participate in cell transformation and multiplication by acting as tumour oncogenes or suppressors; therefore, harnessing miRNAs may provide promising cancer therapeutics. Another major function of miRNAs is their activity as critical regulatory vehicles eliciting important regulatory processes in anti-tumour immunity through their influence on the development, differentiation and activation of various immune cells of both innate and adaptive immunity. This review aims to summarise recent findings focusing on the regulatory mechanisms of the development, differentiation, and proliferative aspects of the major immune populations by a diverse profile of miRNAs and may enrich our current understanding of the involvement of miRNAs in anti-tumour immunity.

Over-expression of deubiquitinating enzyme USP14 in lung adenocarcinoma promotes proliferation through the accumulation of ß-catenin.

The deubiquitinating enzyme USP14 has been identified and biochemically studied, but its role in lung cancer remains to be elucidated. The aim of this study was to evaluate the prognostic significance of USP14 in patients with lung adenocarcinoma and to define its role in lung cancer cell proliferation. USP14 mRNA levels in different non-small cell lung cancer (NSCLC) cell lines were detected by real-time qPCR. USP14 protein levels in surgically resected samples from NSCLC patients, and in NSCLC cell lines, were detected by immunohistochemistry or Western blot. The correlation of USP14 expression with clinical characteristics and prognosis was determined by survival analysis. After silencing USP14, cell proliferation was assessed by MTT assay and the cell cycle was measured by FACS assay. It was found that USP14 expression was upregulated in NSCLC cells, especially in adenocarcinoma cells. Over-expression of USP14 was associated with shorter overall survival of patients. Downregulation of USP14 expression arrested the cell cycle, which may be related to ß-catenin degradation. Over-expression of USP14 was associated with poor prognosis in NSCLC patients and promoted tumor cell proliferation, which suggests that USP14 is a tumor-promoting factor and a promising therapeutic target for NSCLC.