The role of TXNDC5 in castration-resistant prostate cancer—involvement of androgen receptor signaling pathway

The role and mechanism of TXNDC5 in cardio-oncology: Killing two birds with one stone?

Cardio-oncology has emerged as a new translational and clinical field owing to the growing repertory of cancer therapy. To date, there is a lack of effective pharmacological therapy to target cardiotoxicity. Cardio-oncology, which began by investigating the negative effects of cancer medicines on cardiovascular system, has since grown to include research into the similarities between cardiovascular disease (CVD) and cancer. Thioredoxin domain-containing protein 5 (TXNDC5) belongs to the protein disulfide isomerase (PDI) family. Many diseases, including CVD and cancer, improperly express TXNDC5. This review provides a comprehensive analysis of the expression patterns of TXNDC5 in diseases. It outlines the processes via which TXNDC5 contributes to the advancement of malignant diseases such as CVD and cancer. Additionally, it summarizes prospective therapeutic approaches that can be used to target TXNDC5 for the treatment of these diseases. This will offer novel perspectives for enhancing anticancer therapy and advancing cardio-oncology research and drug development.

Parecoxib Enhances Resveratrol against Human Colorectal Cancer Cells through Akt and TXNDC5 Inhibition and MAPK Regulation

In this study, we discovered the mechanisms underlying parecoxib and resveratrol combination's anti-cancer characteristics against human colorectal cancer DLD-1 cells. We studied its anti-proliferation and apoptosis-provoking effect by utilizing cell viability 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, fluorescence microscope, gene overexpression, Western blot, and flow cytometry analyses. Parecoxib enhanced the ability of resveratrol to inhibit cell viability and increase apoptosis. Parecoxib in combination with resveratrol strongly enhanced apoptosis by inhibiting the expression of thioredoxin domain containing 5 (TXNDC5) and Akt phosphorylation. Parecoxib enhanced resveratrol-provoked c-Jun N-terminal kinase (JNK) and p38 phosphorylation. Overexpression of TXNDC5 and repression of JNK and p38 pathways significantly reversed the inhibition of cell viability and stimulation of apoptosis by the parecoxib/resveratrol combination. This study presents evidence that parecoxib enhances the anti-cancer power of resveratrol in DLD-1 colorectal cancer cells via the inhibition of TXNDC5 and Akt signaling and enhancement of JNK/p38 MAPK pathways. Parecoxib may be provided as an efficient drug to sensitize colorectal cancer by resveratrol.

Molecular landscape for risk prediction and personalized therapeutics of castration-resistant prostate cancer: at a glance

Prostate cancer (PCa) is commonly occurred with high incidence in men worldwide, and many patients will be eventually suffered from the dilemma of castration-resistance with the time of disease progression. Castration-resistant PCa (CRPC) is an advanced subtype of PCa with heterogeneous carcinogenesis, resulting in poor prognosis and difficulties in therapy. Currently, disorders in androgen receptor (AR)-related signaling are widely acknowledged as the leading cause of CRPC development, and some non-AR-based strategies are also proposed for CRPC clinical analyses. The initiation of CRPC is a consequence of abnormal interaction and regulation among molecules and pathways at multi-biological levels. In this study, CRPC-associated genes, RNAs, proteins, and metabolites were manually collected and integrated by a comprehensive literature review, and they were functionally classified and compared based on the role during CRPC evolution, i.e., drivers, suppressors, and biomarkers, etc. Finally, translational perspectives for data-driven and artificial intelligence-powered CRPC systems biology analysis were discussed to highlight the significance of novel molecule-based approaches for CRPC precision medicine and holistic healthcare.

Thioredoxin Domain Containing 5 (TXNDC5): Friend or Foe?

This review focuses on the thioredoxin domain containing 5 (TXNDC5), also known as endoplasmic reticulum protein 46 (ERp46), a member of the protein disulfide isomerase (PDI) family with a dual role in multiple diseases. TXNDC5 is highly expressed in endothelial cells, fibroblasts, pancreatic β-cells, liver cells, and hypoxic tissues, such as cancer endothelial cells and atherosclerotic plaques. TXNDC5 plays a crucial role in regulating cell proliferation, apoptosis, migration, and antioxidative stress. Its potential significance in cancer warrants further investigation, given the altered and highly adaptable metabolism of tumor cells. It has been reported that both high and low levels of TXNDC5 expression are associated with multiple diseases, such as arthritis, cancer, diabetes, brain diseases, and infections, as well as worse prognoses. TXNDC5 has been attributed to both oncogenic and tumor-suppressive features. It has been concluded that in cancer, TXNDC5 acts as a foe and responds to metabolic and cellular stress signals to promote the survival of tumor cells against apoptosis. Conversely, in normal cells, TXNDC5 acts as a friend to safeguard cells against oxidative and endoplasmic reticulum stress. Therefore, TXNDC5 could serve as a viable biomarker or even a potential pharmacological target.

The role and mechanism of TXNDC5 in disease progression

Thioredoxin domain containing protein-5 (TXNDC5), also known as endothelial protein-disulfide isomerase (Endo-PDI), is confined to the endoplasmic reticulum through the structural endoplasmic reticulum retention signal (KDEL), is a member of the PDI protein family and is highly expressed in the hypoxic state. TXNDC5 can regulate the rate of disulfide bond formation, isomerization and degradation of target proteins through its function as a protein disulfide isomerase (PDI), thereby altering protein conformation, activity and improving protein stability. Several studies have shown that there is a significant correlation between TXNDC5 gene polymorphisms and genetic susceptibility to inflammatory diseases such as rheumatoid, fibrosis and tumors. In this paper, we detail the expression characteristics of TXNDC5 in a variety of diseases, summarize the mechanisms by which TXNDC5 promotes malignant disease progression, and summarize potential therapeutic strategies to target TXNDC5 for disease treatment.

Endoplasmic Reticulum Protein TXNDC5 Interacts with PRDX6 and HSPA9 to Regulate Glutathione Metabolism and Lipid Peroxidation in the Hepatic AML12 Cell Line

Non-alcoholic fatty liver disease or steatosis is an accumulation of fat in the liver. Increased amounts of non-esterified fatty acids, calcium deficiency, or insulin resistance may disturb endoplasmic reticulum (ER) homeostasis, which leads to the abnormal accumulation of misfolded proteins, activating the unfolded protein response. The ER is the primary location site for chaperones like thioredoxin domain-containing 5 (TXNDC5). Glutathione participates in cellular oxidative stress, and its interaction with TXNDC5 in the ER may decrease the disulfide bonds of this protein. In addition, glutathione is utilized by glutathione peroxidases to inactivate oxidized lipids. To characterize proteins interacting with TXNDC5, immunoprecipitation and liquid chromatography-mass spectrometry were used. Lipid peroxidation, reduced glutathione, inducible phospholipase A2 (iPLA2) and hepatic transcriptome were assessed in the AML12 and TXNDC5-deficient AML12 cell lines. The results showed that HSPA9 and PRDX6 interact with TXNDC5 in AML12 cells. In addition, TXNDC5 deficiency reduced the protein levels of PRDX6 and HSPA9 in AML12. Moreover, lipid peroxidation, glutathione and iPLA2 activities were significantly decreased in TXNDC5-deficient cells, and to find the cause of the PRDX6 protein reduction, proteasome suppression revealed no considerable effect on it. Finally, hepatic transcripts connected to PRDX6 and HSPA9 indicated an increase in the Dnaja3, Mfn2 and Prdx5 and a decrease in Npm1, Oplah, Gstp3, Gstm6, Gstt1, Serpina1a, Serpina1b, Serpina3m, Hsp90aa1 and Rps14 mRNA levels in AML12 KO cells. In conclusion, the lipid peroxidation system and glutathione mechanism in AML12 cells may be disrupted by the absence of TXNDC5, a novel protein-protein interacting partner of PRDX6 and HSPA9.

Curcumin as a therapeutic agent in cancer therapy: Focusing on its modulatory effects on circular RNAs

Curcumin, a natural polyphenol compound, has been identified as an effective therapeutic agent against cancer that exerts its anti-tumor activities by up/downregulating signaling mediators and modulating various cellular processes, including angiogenesis, autophagy, apoptosis, metastasis, and epithelial-mesenchymal transition (EMT). Since almost 98% of genomic transcriptional production is noncoding RNAs in humans, there is evidence that curcumin exerts therapeutic effects through the alterations of noncoding RNAs in various types of cancers. Circular RNAs (circRNAs) are formed by the back-splicing of immature mRNAs and have several functions, including functioning as miRNA sponges. It has been shown that curcumin modulated various circRNAs, including circ-HN1, circ-PRKCA, circPLEKHM3, circZNF83, circFNDC3B, circ_KIAA1199, circRUNX1, circ_0078710, and circ_0056618. The modulation of these circRNAs targeted the expression of mRNAs and modified various signaling pathways and hallmarks of cancer. In this article, we reviewed the pharmacokinetics of curcumin, its anti-cancer activities, as well as the biology and structure of circRNAs. Our main focus was on how curcumin exerts anti-cancer functions by modulating circRNAs and their target mRNAs and pathways.

Identification of thioredoxin domain containing family members' expression pattern and prognostic value in diffuse gliomas via in silico analysis

BACKGROUND

Gliomas are the most prevalent primary tumors of the central nervous system. Their aggressive nature and the obstacles arising during therapy highlights the importance of finding new prognostic markers and therapy targets for gliomas. TXNDC genes are members of the thioredoxin superfamily and were shown to play a role in redox homeostasis, protein folding, electron transfer and also acting as cellular adapters. The well known contribution of these processes in cancer progression prompted us to investigate if TXNDC family members may also play a role in carcinogenesis, in particular diffuse gliomas.

METHODS

The present study used in silico analysis tools GEPIA, UCSC Xena, Gliovis, cBioPortal, and Ivy GAP to evaluate the expression pattern, prognostic value and clinical significance of TXNDC family members in diffuse gliomas.

RESULTS

Our analysis showed that TXNDC family members' expression pattern differ between tumors and healthy tissues and among tumors with different grades. The detailed analysis of TXNDC5 in glioma pathogenesis revealed that TXNDC5 expression is associated with more aggressive clinical and molecular features and poor therapy success both in LGG and GBM samples. Kaplan-Meier survival curves represented a worse prognosis for patients with leveated TXNDC5 levels in LGG and all grade glioma patients. The levels of TXNDC5 was shown to be possibly regulated by hypoxia-ER stress axis and a potential mechanism for TXNDC5-driven glioma progression was found to be extracellular matrix (ECM) production which is known to promote tumor aggressiveness.

CONCLUSIONS

Our results uncovered the previously unknown role of TXNDC family members in glioma pathogenesis and showed that TXNDC5 levels could serve as a predictor of clinical outcome and therapy success and may very well be used for targeted therapy.

Protein Disulfide Isomerases Function as the Missing Link Between Diabetes and Cancer

Significance: Diabetes has long been recognized as an independent risk factor for cancer, but there is insufficient mechanistic understanding of biological mediators that bridge two disorders together. Understanding the pathogenic association between diabetes and cancer has become the focus of many studies, and findings are potentially valuable for the development of effective preventive or therapeutic strategies for both disorders. Recent Advances: A summary of literature reveals a possible connection between diabetes and cancer through the family of protein disulfide isomerase (PDI). Historical as well as the most recent findings on the structure, biochemistry, and biology of the PDI family were summarized in this review. Critical Issues: PDIs in general function as redox enzymes and protein chaperones to control the quality of proteins by correcting or otherwise eliminating misfolded proteins in conditions of oxidative stress and endoplasmic reticulum stress, respectively. However, individual members of the PDI family may contribute uniquely to the pathogenesis of diabetes and cancer. Studies of exemplary members such as protein disulfide isomerase-associated (PDIA) 1, PDIA6, and PDIA15 were reviewed to highlight their contributions in the pathogenesis of diabetes and cancer and how they can be potential links bridging the two disorders through the cross talk of signaling pathways. Future Directions: Apparently ubiquitous presence of the PDIs creates difficulties and challenges for scientific community to develop targeted therapeutics for the treatment of diabetes and cancer simultaneously. Understanding molecular contribution of individual PDI in the context of specific disease may provide some insights into the development of mechanism-based target-directed therapeutics. Antioxid. Redox Signal. 37, 1191-1205.

The role and mechanism of TXNDC5 in diseases

Thioredoxin domain-containing protein 5 (TXNDC5) is a member of the protein disulfide isomerase (PDI) family. It can promote the formation and rearrangement of disulfide bonds, ensuring proper protein folding. TXNDC5 has three Trx-like domains, which can act independently to introduce disulfide bonds rapidly and disorderly. TXNDC5 is abnormally expressed in various diseases, such as cancer, rheumatoid arthritis (RA), etc. It can protect cells from oxidative stress, promote cell proliferation, inhibit apoptosis and promote the progression of disease. Aberrant expression of TXNDC5 in different diseases suggests its role in disease diagnosis. In addition, targeting TXNDC5 in the treatment of diseases has shown promising application prospects. This article reviews the structure and function of TXNDC5 as well as its role and mechanism in cancer, RA and other diseases.

PPFIA4 promotes castration-resistant prostate cancer by enhancing mitochondrial metabolism through MTHFD2

Background

The development of castration-resistant prostate cancer (CRPC) remains a major obstacle in the treatment of prostate cancer (PCa). Dysregulated mitochondrial function has been linked to the initiation and progression of diverse human cancers. Deciphering the novel molecular mechanisms underlying mitochondrial function may provide important insights for developing novel therapeutics for CRPC.

Methods

We investigate the expression of the protein tyrosine phosphatase receptor type F polypeptide interacting protein alpha 4 (PPFIA4) using public datasets and tumor specimens from PCa cases by immunohistochemistry. Gain- and loss-of-function studies are performed in PCa cell lines and mouse models of subcutaneous xenograft to characterize the role of PPFIA4 in CRPC. Gene expression regulation is evaluated by a series of molecular and biochemical experiments in PCa cell lines. The therapeutic effects of methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) inhibitor combined enzalutamide are assessed using in vitro functional assays and in vivo mouse models.

Results

We show that the increase of PPFIA4 exacerbates aggressive phenotype resembling CRPC. A fraction of PPFIA4 localizes to mitochondria and interacts with MTHFD2, a key enzyme for one-carbon metabolism. Androgen deprivation increases the translocation of PPFIA4 into mitochondria and increases the interaction between PPFIA4 and MTHFD2, which result in the elevation of tyrosine phosphorylated MTHFD2. Consequently, the levels of NADPH synthesis increase, resulting in protection against androgen deprivation-induced mitochondrial dysfunction, as well as promotion of tumor growth. Clinically, PPFIA4 expression is significantly increased in CRPC tissues compared with localized PCa ones. Importantly, an MTHFD2 inhibitor, DS18561882, combined with enzalutamide can significantly inhibit CRPC cell proliferation in vitro and tumor growth in vivo.

Conclusion

Overall, our findings reveal a PPFIA4-MTHFD2 complex in mitochondria that links androgen deprivation to mitochondrial metabolism and mitochondrial dysfunction, which suggest a potential strategy to inhibit CRPC progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02331-3.

Circ_0078710 promotes the development of liver cancer by upregulating TXNDC5 via miR-431-5p

INTRODUCTION AND OBJECTIVES

Liver cancer, with high recurrence and metastasis rate, is a common malignant tumor. Circular RNA_0078710 (circ_0078710) has been shown to be take part in the advance of hepatocellular carcinoma. However, the interaction between circ_0091579 and microRNA-431-5p (miR-431-5p) in liver cancer has not been studied.

MATERIALS AND METHODS

The expressions of circ_0078710, miR-431-5p and Thioredoxin domain-containing 5 (TXNDC5) in liver cancer tissues and cells were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The effect of cric_0078710 in liver cancer cells was assessed by Cell Counting Kit-8 (CCK-8) assay, Transwell, flow cytometry and Dual-luciferase reporter assay. Glycolysis metabolism was examined by lactate production, glucose uptake and ATP level. The protein levels of ki-67, bax and TXNEC5 were tested by western blot. The role of circ_0078710 in vivo was determined by animal study.

RESULTS

Circ_0078710 and TXNDC5 were notably expressed in liver cancer tissues and cells. Circ_0078710 knockdown diminished proliferation, migration, invasion and glycolytic metabolism of huh7 and Hep3B cells, and accelerated cell apoptosis. MiR-431-5p is the target of circ_0078710, and silence circ_0078710 can inhibit the malignant behavior and glycolysis of hepatocellular carcinoma (HCC) cells by releasing miR-431-5p. In addition, TXNDC5 was a target of miR-431-5p, and overexpression of TXNDC5 restored cell proliferation and glycolysis inhibition due to miR-431-5p. Animal experiments made clear the anti-tumor effect of circ_0078710 knockdown.

CONCLUSION

Circ_0078710 promotes the progression of liver cancer by regulating TXNDC5 expression by targeting miR-431-5p. These results demonstrate that circ_0078710 could be a remedy target for liver cancer.

The aberrant upregulation of exon 10-inclusive SREK1 through SRSF10 acts as an oncogenic driver in human hepatocellular carcinoma

Deregulation of alternative splicing is implicated as a relevant source of molecular heterogeneity in cancer. However, the targets and intrinsic mechanisms of splicing in hepatocarcinogenesis are largely unknown. Here, we report a functional impact of a Splicing Regulatory Glutamine/Lysine-Rich Protein 1 (SREK1) variant and its regulator, Serine/arginine-rich splicing factor 10 (SRSF10). HCC patients with poor prognosis express higher levels of exon 10-inclusive SREK1 (SREK1^L). SREK1^L can sustain BLOC1S5-TXNDC5 (B-T) expression, a targeted gene of nonsense-mediated mRNA decay through inhibiting exon-exon junction complex binding with B-T to exert its oncogenic role. B-T plays its competing endogenous RNA role by inhibiting miR-30c-5p and miR-30e-5p, and further promoting the expression of downstream oncogenic targets SRSF10 and TXNDC5. Interestingly, SRSF10 can act as a splicing regulator for SREK1^L to promote hepatocarcinogenesis via the formation of a SRSF10-associated complex. In summary, we demonstrate a SRSF10/SREK1^L/B-T signalling loop to accelerate the hepatocarcinogenesis.

Alternative splicing is dysregulated in hepatocellular carcinoma. Here, the authors investigate the role of the splice variant of Splicing Regulatory Glutamic Acid and Lysine Rich Protein 1 (SREK1) and its upstream regulator, Serine/arginine-rich splicing factor 10 (SRSF10) in sustaining the oncogenic signal.

LncRNA-ENST00000556926 regulates the proliferation, apoptosis and mRNA transcriptome of malignant-transformed BEAS-2B cells induced by coal tar pitch

As a byproduct of coal tar distillation, coal tar pitch (CTP) has been proven to be carcinogenic to human. However, the mechanisms of lung cancer induced by CTP are still unclear. It has been shown that long non-coding RNAs (LncRNAs) play an important role in the development of human cancers. This study aims to investigate the effect of LncRNA-ENST00000556926 on malignant-transformed human bronchial epithelial (BAES-2B) cells induced by coal tar pitch extracts (CTPE). In this study, BEAS-2B cells were treated with 2.4 μg/ml of CTPE for 72 h and then passaged; and the cells were treated 4 times in the same procedure, then passaged until passage 30 (CTPE30). Cell counting kit-8 (CCK-8) assay was used to detect cell viability, then cell cycle and apoptosis were analyzed by flow cytometry, and transcriptome sequencing analysis was used to detect differentially expressed mRNAs after interference of ENST00000556926. The results indicated that the expression of ENST00000556926 in CTPE30 group was significantly higher compared with control group. Furthermore, after interfering the expression of ENST00000556926, cell viability was inhibited, and cell cycle was arrested while apoptosis of malignant-transformed BEAS-2B cells was promoted. Moreover, a total of 159 differentially expressed mRNAs were screened out after interference of ENST00000556926, including 62 up-regulated mRNAs and 97 down-regulated mRNAs. In addition, knockdown of ENST00000556926 decreased the expression of thioredoxin domain containing 5 (TXNDC5) and FOXD1. In conclusion, LncRNA-ENST00000556926 could regulate the proliferation, apoptosis and mRNA transcriptome of malignant-transformed BEAS-2B cells induced by CTP, which may provide a novel treatment strategy for lung cancer.

Altered protein S-glutathionylation depicts redox imbalance triggered by transition metal oxide nanoparticles in a breastfeeding system

Nanosafety has become a public concern following nanotechnology development. By now, attention has seldom been paid to breastfeeding system, which is constructed by mammary physiological structure and derived substances (endogenous or exogenous), cells, tissues, organs, and individuals (mother and child), connecting environment and organism, and spans across mother-child dyad. Thus, breastfeeding system is a center of nutrients transport and a unique window of toxic susceptibility in the mother-child dyad. We applied metabolomics combined with redox proteomics to depict how nanoparticles cause metabolic burden via their spontaneous redox cycling in lactating mammary glands. Two widely used nanoparticles [titanium dioxide (nTiO₂) and zinc oxide (nZnO)] were exposed to lactating mice via intranasal administration. Biodistribution and biopersistence of nTiO₂ and nZnO in mammary glands destroyed its structure, reflective of significantly reduced claudin-3 protein level by 32.1% (P < 0.01) and 47.8% (P < 0.01), and significantly increased apoptosis index by 85.7 (P < 0.01) and 100.3 (P < 0.01) fold change, respectively. Airway exposure of nTiO₂ trended to reduced milk production by 22.7% (P = 0.06), while nZnO significantly reduced milk production by 33.0% (P < 0.01). Metabolomics analysis revealed a metabolic shift by nTiO₂ or nZnO, such as increased glycolysis (nTiO₂: fold enrichment = 3.31, P < 0.05; nZnO: fold enrichment = 3.68, P < 0.05), glutathione metabolism (nTiO₂: fold enrichment = 5.57, P < 0.01; nZnO: fold enrichment = 4.43, P < 0.05), and fatty acid biosynthesis (nTiO₂: fold enrichment = 3.52, P < 0.05; nZnO: fold enrichment = 3.51, P < 0.05) for tissue repair at expense of lower milk fat synthesis (35.7% reduction by nTiO₂; 51.8% reduction by nZnO), and finally led to oxidative stress of mammary glands. The increased GSSG/GSH ratio (57.5% increase by nTiO₂; 105% increase by nZnO) with nanoparticle exposure confirmed an alteration in the redox state and a metabolic shift in mammary glands. Redox proteomics showed that nanoparticles induced S-glutathionylation (SSG) modification at Cys sites of proteins in a nanoparticle type-dependent manner. The nTiO₂ induced more protein SSG modification sites (nTiO₂: 21; nZnO:16), whereas nZnO induced fewer protein SSG modification sites but at deeper SSG levels (26.6% higher in average of nZnO than that of nTiO₂). In detail, SSG modification by nTiO₂ was characterized by Ltf at Cys⁴²³ (25.3% increase), and Trf at Cys^386;395;583 (42.3%, 42.3%, 22.8% increase) compared with control group. While, SSG modification by nZnO was characterized by Trfc at Cys³⁶⁵ (71.3% increase) and Fasn at Cys¹⁰¹⁰ (41.0% increase). The discovery of SSG-modified proteins under airway nanoparticle exposure further supplemented the oxidative stress index and mammary injury index, and deciphered precise mechanisms of nanotoxicity into a molecular level. The unique quantitative site-specific redox proteomics and metabolomics can serve as a new technique to identify nanotoxicity and provide deep insights into nanoparticle-triggered oxidative stress, contributing to a healthy breastfeeding environment.

Increased Expression of Sema3C Indicates a Poor Prognosis and Is Regulated by miR-142-5p in Glioma

Sema3C has been reported to promote glioma stem cells self-renewal and glioblastoma growth. However, the prognostic value and the regulatory mechanism for its abnormal expression in glioma remain poorly understood. In the current study, the immunohistochemistry results demonstrated that Sema3C was overexpressed in 169 of 216 (78.2%) interpretable glioma patients compared with 3 of 15 (20.0%) interpretable non-neoplastic brain cases (p = 0.0001). Sema3C overexpression was significantly associated with histologic type (p = 0.008), high Ki67 labeling index (p = 0.02), tumor grade (p = 0.002) and wild type IDH1 (p = 0.0001). Importantly, its overexpression predicts the shorter overall survival of glioma patients (p = 0.0017), especially the ones with high grade (p = 0.0124). Functionally, Sema3C silencing significantly reduced the proliferation and invasion of glioma cells, indicating an oncogenic role of Sema3C in glioma in vitro. To elucidate the reason accounting for its overexpression, it is identified miR-142-5p as a tumor suppressor that directly targets Sema3C in glioma cells. miR-142-5p and Sema3C were co-regulators of epithelial-mesenchymal transition. Clinically, miR-142-5p expression was conversely related with Sema3C expression in glioma samples. Together, we identified that Sema3C could promote the progression of glioma and its expression was negatively regulated by miR-142-5p in vitro. Thus, the miR-142-5p-Sema3C axis plays importantly in glioma and holds potential to be therapeutic targets as well.

The NRF2, Thioredoxin, and Glutathione System in Tumorigenesis and Anticancer Therapies

Cancer remains an elusive, highly complex disease and a global burden. Constant change by acquired mutations and metabolic reprogramming contribute to the high inter- and intratumor heterogeneity of malignant cells, their selective growth advantage, and their resistance to anticancer therapies. In the modern era of integrative biomedicine, realizing that a personalized approach could benefit therapy treatments and patients' prognosis, we should focus on cancer-driving advantageous modifications. Namely, reactive oxygen species (ROS), known to act as regulators of cellular metabolism and growth, exhibit both negative and positive activities, as do antioxidants with potential anticancer effects. Such complexity of oxidative homeostasis is sometimes overseen in the case of studies evaluating the effects of potential anticancer antioxidants. While cancer cells often produce more ROS due to their increased growth-favoring demands, numerous conventional anticancer therapies exploit this feature to ensure selective cancer cell death triggered by excessive ROS levels, also causing serious side effects. The activation of the cellular NRF2 (nuclear factor erythroid 2 like 2) pathway and induction of cytoprotective genes accompanies an increase in ROS levels. A plethora of specific targets, including those involved in thioredoxin (TRX) and glutathione (GSH) systems, are activated by NRF2. In this paper, we briefly review preclinical research findings on the interrelated roles of the NRF2 pathway and TRX and GSH systems, with focus given to clinical findings and their relevance in carcinogenesis and anticancer treatments.

TXNDC5 protects synovial fibroblasts of rheumatoid arthritis from the detrimental effects of endoplasmic reticulum stress

TXNDC5 is an endoplasmic reticulum (ER)-resident chaperone that protects the endothelium from secondary effects of ER stress. Previous studies by the current authors identified TXNDC5 as a key pathological factor in promoting the inflammatory phenotype of fibroblast-like synoviocytes (FLSs) from rheumatoid arthritis (RA). However, its activity in RA FLSs under ER stress remains unclear. The current study found that TXNDC5 is responsive to ER stress in RA FLSs since its expression was induced by ER stress at both the endogenous and secretory level. A functional study indicated that silencing TXNDC5 reduced the viability of RA FLSs more markedly in the presence of ER stressors. In contrast, rhTXNDC5 attenuated a decrease in cell viability as a result of ER stress. Moreover, silencing TXNDC5 attenuated the induction of IL-6 and IL-8 from RA FLSs in response to ER stress. In addition, rhTXNDC5 induced a greater increase in VEGF production during ER stress. These findings confirm the pro-survival and pro-inflammation roles of TXNDC5 under ER stress in RA FLSs. TXNDC5 appears to act as a mediator linking ER stress and inflammation of RA.

TXNDC12 promotes EMT and metastasis of hepatocellular carcinoma cells via activation of β-catenin

Metastasis is one of the main contributors to the poor prognosis of hepatocellular carcinoma (HCC). However, the underlying mechanism of HCC metastasis remains largely unknown. Here, we showed that TXNDC12, a thioredoxin-like protein, was upregulated in highly metastatic HCC cell lines as well as in portal vein tumor thrombus and lung metastasis tissues of HCC patients. We found that the enforced expression of TXNDC12 promoted metastasis both in vitro and in vivo. Subsequent mechanistic investigations revealed that TXNDC12 promoted metastasis through upregulation of the ZEB1-mediated epithelial-mesenchymal transition (EMT) process. We subsequently showed that TXNDC12 overexpression stimulated the nuclear translocation and activation of β-catenin, a positive transcriptional regulator of ZEB1. Accordingly, we found that TXNDC12 interacted with β-catenin and that the thioredoxin-like domain of TXNDC12 was essential for the interaction between TXNDC12 and β-catenin as well as for TXNDC12-mediated β-catenin activation. Moreover, high levels of TXNDC12 in clinical HCC tissues correlated with elevated nuclear β-catenin levels and predicted worse overall and disease-free survival. In summary, our study demonstrated that TXNDC12 could activate β-catenin via protein-protein interaction and promote ZEB1-mediated EMT and HCC metastasis.

HERG1 promotes esophageal squamous cell carcinoma growth and metastasis through TXNDC5 by activating the PI3K/AKT pathway

Background

The human ether a-go-go-related gene 1 (HERG1) is involved in tumor progression; however, its role in esophageal squamous cell carcinoma (ESCC) is not well studied. This study investigated HERG1 function in ESCC progression and elucidated the underlying mechanisms.

Methods

The prognostic value of HERG1 was determined by immunohistochemistry in ESCC biopsies. Cell growth and proliferation were analyzed by colony formation and methyl thiazolyl tetrazolium assays. Cell migration and invasion were analyzed by wound healing and Boyden transwell assays. Epithelial-mesenchymal transition (EMT) was evaluated by immunoblotting and quantitative polymerase chain reaction (qPCR). A xenograft mouse model was used to validate the tumorigenic and metastatic roles of HERG1 in vivo.

Results

HERG1 expression was overall higher in ESCC tissues compared to adjacent non-tumor tissues. A retrospective analysis of 349 patients with ESCC (stages I–IV) confirmed increased HERG1 expression was associated with disease progression and higher mortality rate. The overall survival of the patients was significantly worse when their tumors displayed higher HERG1 expression. HERG1 knockdown reduced tumor growth and metastasis in athymic mice. HERG1 affected the proliferation, migration, and invasion of two ESCC cell lines (TE-1 and KYSE-30). Changes in HERG1 expression affected the expression of cell cycle- and EMT-related proteins; these effects were reversed by altering the expression of thioredoxin domain-containing protein 5 (TXNDC5), which is also associated with the clinicopathological characteristics of patients with ESCC and is relevant to HERG1 in pathological biopsies. Additionally, HERG1 expression altered phosphoinositide 3-kinase (PI3K) and AKT phosphorylation, thereby affecting TXNDC5 expression.

Conclusions

HERG1 contributes to poor prognosis in patients with ESCC by promoting ESCC cell proliferation, migration, and invasion via TXNDC5 through the PI3K/AKT signaling pathway. Our findings provided novel insights into the pathology of ESCC and role of HERG1 in tumor progression, suggesting that targeting HERG1 has potential diagnostic and therapeutic value for ESCC treatment.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1284-y) contains supplementary material, which is available to authorized users.

The redox regulator sulfiredoxin forms a complex with thioredoxin domain-containing 5 protein in response to ER stress in lung cancer cells

Sulfiredoxin (Srx) reduces hyperoxidized 2-cysteine-containing peroxiredoxins (Prxs) and protects cells against oxidative stress. Previous studies have shown that Srx is highly expressed in primary specimens of lung cancer patients and plays a pivotal role in lung tumorigenesis and cancer progression. However, the oncogenic mechanisms of Srx in cancer are incompletely understood. In this study, we found that Srx knockdown sensitizes lung cancer cells to endoplasmic reticulum (ER) stress-induced cell death. Through MS analysis, we determined that Srx forms a complex with the ER-resident protein thioredoxin domain-containing protein 5 (TXNDC5). Using reciprocal co-immunoprecipitation, immunofluorescence imaging, subcellular fractionation, and domain-mapping assays with site-specific mutagenesis and purified recombinant proteins, we further characterized the Srx-TXNDC5 interaction. In response to ER stress but not to oxidative stress, Srx exhibits an increased association with TXNDC5, facilitating the retention of Srx in the ER. Of note, TXNDC5 knockdown in lung cancer cells inhibited cell proliferation and repressed anchorage-independent colony formation and migration, but increased cell invasion and activation of mitogen-activated protein kinases. Using immunohistochemical staining, we demonstrate that TXNDC5 is highly expressed in patient-derived lung cancer specimens. Bioinformatics analysis of publicly available data sets revealed that those with high Srx levels have significantly shorter survival and that those with high TXNDC5 levels have longer survival. We conclude that the cellular levels of Srx and TXNDC5 may be useful as biomarkers to predict the survival of individuals with lung cancer.

TXNDC9 promotes hepatocellular carcinoma progression by positive regulation of MYC-mediated transcriptional network

The thioredoxin domain containing proteins are a group of proteins involved in redox regulation and have been recently reported to be associated with tumor progression. However, the role of thioredoxin proteins in hepatocellular carcinoma (HCC) remains largely unknown. Here in our study, we demonstrated that thioredoxin domain containing protein 9 (TXNDC9) was over-expressed in HCC and promoted HCC progression. We found that TXNDC9 expression was amplified in HCC tissues and associated with an advanced grade of HCC. And, we demonstrated that overexpression of TXNDC9 was correlated with poor prognosis of HCC. Furthermore, by using CRISPR-Cas9 mediated TXNDC9 knockout and RNA-seq analysis, we found that TXNDC9 accelerated HCC proliferation regulation. Moreover, we demonstrated that TXNDC9 directly interacted with MYC and knockout/knockdown of TXNDC9 decreased the protein levels of MYC and inhibited MYC-mediated transcriptional activation of its targets. Besides, we identified that TXNDC9 was trans-activated by FOXA1, JUND, and FOSL2 in HCC. Taken together, our study unveiled an oncogenic role of TXNDC9 in HCC and provided a mechanistic insight into the TXNDC9 mediated gene regulation network during HCC development.

Exploration of the diagnostic value and molecular mechanism of miR‑1 in prostate cancer: A study based on meta‑analyses and bioinformatics

Prostate cancer (PCa) remains a principal issue to be addressed in male cancer-associated mortality. Therefore, the present study aimed to examine the clinical value and associated molecular mechanism of microRNA (miR)-1 in PCa. A meta-analysis was conducted to evaluate the diagnosis of miR-1 in PCa via Gene Expression Omnibus and ArrayExpress datasets, The Cancer Genome Atlas miR-1 expression data and published literature. It was identified that expression of miR-1 was significantly downregulated in PCa. Decreased miR-1 expression possessed moderate diagnostic value, with area under the curve, sensitivity, specificity and odds ratio values at 0.73, 0.77, 0.57 and 4.60, respectively. Using bioinformatics methods, it was revealed that a number of pathways, including the ‘androgen receptor signaling pathway’, ‘androgen receptor activity’, ‘transcription factor binding’ and ‘protein processing in the endoplasmic reticulum’, were important in PCa. A total of seven hub genes, including phosphoribosylaminoimidazole carboxylase and phosphoribosylaminoimidazolesuccin ocarboxamide synthase (PAICS), cadherin 1 (CDH1), SRC proto-oncogene, non-receptor tyrosine kinase, twist family bHLH transcription factor 1 (TWIST1), ZW10 interacting kinetochore protein (ZWINT), PCNA clamp associated factor (KIAA0101) and androgen receptor, among which, five (PAICS, CDH1, TWIST1, ZWINT and KIAA0101) were significantly upregulated and negatively correlated with miR-1, were identified as key miR-1 target genes in PCa. Additionally, it was investigated whether miR-1 and its hub genes were associated with clinical features, including age, tumor status, residual tumor, lymph node metastasis, pathological T stage and prostate specific antigen level. Collectively the results suggest that miR-1 may be involved in the progression of PCa, and consequently be a promising diagnostic marker. The ‘androgen receptor signaling pathway’, ‘androgen receptor activity’, ‘transcription factor binding’ and ‘protein processing in the endoplasmic reticulum’ may be crucial interactive pathways in PCa. Furthermore, PAICS, CDH1, TWIST1, ZWINT and KIAA0101 may serve as crucial miR-1 target genes in PCa.

A critical role of the thioredoxin domain containing protein 5 (TXNDC5) in redox homeostasis and cancer development

Correct folding of nascent peptides occurs in the endoplasmic reticulum (ER). It is a complicate process primarily accomplished by the coordination of multiple redox proteins including members of the protein disulfide isomerase (PDI) family. As a critical member of the PDI family, thioredoxin domain containing protein 5 (TXNDC5) assists the folding of newly synthesized peptides to their mature form through series of disulfide bond exchange reactions. Interestingly, TXNDC5 is frequently found overexpressed in specimens of many human diseases including various types of cancer. In this review, we summarized the biochemical function of TXNDC5 in mammalian cells and the recent progress on the understanding of its role and molecular mechanisms in cancer development. Findings of TXNDC5 in the activation of intracellular signaling pathways, stimulation of cell growth & proliferation, facilitation of cell survival and modulation of extracellular matrix to affect cancer cell invasion and metastasis are reviewed. These published studies suggest that strategies of targeting TXNDC5 can be developed as potentially valuable methods for the treatment of certain types of cancer in patients.

Identification of simvastatin-regulated targets associated with JNK activation in DU145 human prostate cancer cell death signaling

The results of this study show that c-Jun N-terminal kinase (JNK) activation was associated with the enhancement of docetaxel-induced cytotoxicity by simvastatin in DU145 human prostate cancer cells. To better understand the basic molecular mechanisms, we investigated simvastatin-regulated targets during simvastatin-induced cell death in DU145 cells using two-dimensional (2D) proteomic analysis. Thus, vimentin, Ras-related protein Rab-1B (RAB1B), cytoplasmic hydroxymethylglutaryl-CoA synthase (cHMGCS), thioredoxin domain-containing protein 5 (TXNDC5), heterogeneous nuclear ribonucleoprotein K (hnRNP K), N-myc downstream-regulated gene 1 (NDRG1), and isopentenyl-diphosphate Delta-isomerase 1 (IDI1) protein spots were identified as simvastatin-regulated targets involved in DU145 cell death signaling pathways. Moreover, the JNK inhibitor SP600125 significantly inhibited the upregulation of NDRG1 and IDI protein levels by combination treatment of docetaxel and simvastatin. These results suggest that NDRG1 and IDI could at least play an important role in DU145 cell death signaling as simvastatin-regulated targets associated with JNK activation.

MicroRNA-432 functions as a tumor suppressor gene through targeting E2F3 and AXL in lung adenocarcinoma

Abnormal proliferation and drug resistance are the hallmarks of lung adenocarcinoma (LAD). Dispite the advances in diagnosis and therapy, the 5-year survival remains low. Increasing studies regarding its pathological mechanism have been focused on microRNA (miRNA) due to its nodal regulatory properties. This study aims to characterize the expression of miR-432 in LAD and investigate its effects on the proliferation and sensitivity of lung cancer cells to cisplatin. Here, we report that downregulation of miR-432 in LAD tissues was correlated with a higher clinical stage (p = 0.03) and poor prognosis (p = 0.036). Additionally, miR-432 expression was negative correlated with high Ki67 labeling index (p = 0.016) in our cohorts. Functionally, over-expression of miR-432 inhibits cell proliferation through arresting cell cycle and sensitizes tumor cells to cisplatin. Mechanistically, miR-432 functions by directly targeting E2F3 and AXL, and they, in turn, mediate the regulation of miR-432 towards cell proliferation and cisplatin sensitivity. Importantly, miR-432 levels are negatively correlated with the levels of E2F3 and AXL in human LAD tissues. These results demonstrated that miR-432 functions as a tumor-suppressive miRNA and may represent a prognostic parameter and therapeutic target for LAD.

Thioredoxin-1 protects against androgen receptor-induced redox vulnerability in castration-resistant prostate cancer

Androgen deprivation (AD) therapy failure leads to terminal and incurable castration-resistant prostate cancer (CRPC). We show that the redox-protective protein thioredoxin-1 (TRX1) increases with prostate cancer progression and in androgen-deprived CRPC cells, suggesting that CRPC possesses an enhanced dependency on TRX1. TRX1 inhibition via shRNA or a phase I-approved inhibitor, PX-12 (untested in prostate cancer), impedes the growth of CRPC cells to a greater extent than their androgen-dependent counterparts. TRX1 inhibition elevates reactive oxygen species (ROS), p53 levels and cell death in androgen-deprived CRPC cells. Unexpectedly, TRX1 inhibition also elevates androgen receptor (AR) levels under AD, and AR depletion mitigates both TRX1 inhibition-mediated ROS production and cell death, suggesting that AD-resistant AR expression in CRPC induces redox vulnerability. In vivo TRX1 inhibition via shRNA or PX-12 reverses the castration-resistant phenotype of CRPC cells, significantly inhibiting tumor formation under systemic AD. Thus, TRX1 is an actionable CRPC therapeutic target through its protection against AR-induced redox stress.

TXNDC5 is a cervical tumor susceptibility gene that stimulates cell migration, vasculogenic mimicry and angiogenesis by down-regulating SERPINF1 and TRAF1 expression

TXNDC5 (thioredoxin domain-containing protein 5) catalyzes disulfide bond formation, isomerization and reduction. Studies have reported that TXNDC5 expression is increased in some tumor tissues and that its increased expression can predict a poor prognosis. However, the tumorigenic mechanism has not been well characterized. In this study, we detected a significant association between the rs408014 and rs7771314 SNPs at the TXNDC5 locus and cervical carcinoma using the Taqman genotyping method. We also detected a significantly increased expression of TXNDC5 in cervical tumor tissues using immunohistochemistry and Western blot analysis. Additionally, inhibition of TXNDC5 expression using siRNA prevented tube-like structure formation, an experimental indicator of vasculogenic mimicry and metastasis, in HeLa cervical tumor cells. Inhibiting TXNDC5 expression simultaneously led to the increased expression of SERPINF1 (serpin peptidase inhibitor, clade F) and TRAF1 (TNF receptor-associated factor 1), which have been reported to inhibit angiogenesis and metastasis as well as induce apoptosis. This finding was confirmed in Caski and C-33A cervical tumor cell lines. The ability to form tube-like structures was rescued in HeLa cells simultaneously treated with anti-TXNDC5, SERPINF1 and TRAF1 siRNAs. Furthermore, the inhibition of TXNDC5 expression significantly attenuated endothelial tube formation, a marker of angiogenesis, in human umbilical vein endothelial cells. The present study suggests that TXNDC5 is a susceptibility gene in cervical cancer, and high expression of this gene contributes to abnormal angiogenesis, vasculogenic mimicry and metastasis by down-regulating SERPINF1 and TRAF1 expression.

TXNDC5 synergizes with HSC70 to exacerbate the inflammatory phenotype of synovial fibroblasts in rheumatoid arthritis through NF-κB signaling

The upregulated expression of thioredoxin domain-containing protein 5 (TXNDC5) is associated with rheumatoid arthritis in patients and model mice. However, the underlying mechanism by which TXNDC5 influences the pathological activation of rheumatoid arthritis synovial fibroblasts (RASFs) remains unknown. In this study, we show that TXNDC5 expression in RASFs and their cytokine production are significantly upregulated in response to LPS, TNF-α and IL-6, but suppressed by transfection with TXNDC5-siRNA. TXNDC5 is further validated as the direct target of NF-κB signaling. Mechanistically, TXNDC5 directly interacts with heat shock cognate 70 protein (HSC70) to sequester it in the cytoplasm, and HSC70 silencing exerts the same effects as TXNDC5 on the biological activity of RASFs (for example, decreased cell viability, invasion and cytokine production). Furthermore, HSC70 activates NF-κB signaling by destabilizing IκBβ protein in the absence of LPS or facilitating its nuclear translocation in the presence of LPS. Importantly, TXNDC5 can also regulate the activity of NF-κB signaling in a HSC70-IκBβ-dependent manner. Taken together, by linking HSC70 and NF-κB signaling, TXNDC5 plays a pro-inflammatory role in RASFs, highlighting a potential approach to treat RA by blocking the TXNDC5/HSC70 interaction.

Endoplasmic reticulum protein ERp46 in prostate adenocarcinoma

Endoplasmic reticulum (ER) protein ERp46 is a member of the protein disulfide isomerase family of oxidoreductases, which facilitates the reduction of disulfides in proteins and their folding. Accumulation of misfolded proteins has been implicated in cancer. The objectives of the present study were to investigate the role of ERp46 in prostate cancer, its expression and its effects on prostate cancer growth. A tissue microarray with human prostate cancer and normal prostate tissue samples was stained for ERp46 followed by image analysis. Human prostate adenocarcinoma 22Rv1 cells were stably transfected with short hairpin RNA (shRNA) specific for ERp46, a non-effective scrambled control or a plasmid containing full-length human ERp46 cDNA, and cell growth was determined. Subcloned cells were treated with thapsigargin or tunicamycin to induce ER stress and lysates were subjected to western blot analysis for ER stress proteins. Subcutaneous xenografts of parental 22Rv1, ERp46-overexpressing (ERp46+), shERp46 or scrambled control cells were established in male inbred BALB/c nude mice (n=10/group). Tumor growth curves of the xenografts were constructed over a period of 30 days and subsequently the mice were sacrificed and the amount of serum prostate-specific antigen was determined. The results demonstrated increased ERp46 expression levels in prostate cancer tissue samples of Gleason ≥7 compared with normal prostate tissue samples. When ERp46 was stably knocked down using shRNA or overexpressed in prostate carcinoma 22Rv1 cells, tumor growth in vitro and in BALB/c nude mice was inhibited and accelerated, respectively. ERp46 overexpression led to reduced sensitivity to ER stress as indicated by higher half maximal inhibitory concentrations for tunicamycin and thapsigargin in ERp46+ cells. The shERp46 cells lost the ability to upregulate protein disulfide isomerase following tunicamycin-induced ER stress. The present study suggests a role for ERp46 as a therapeutic target in prostate cancer, given its expression profile in human prostate cancer, and its effect on prostate cancer cell growth.

Protein disulfide isomerases: Redox connections in and out of the endoplasmic reticulum

Protein disulfide isomerases are thiol oxidoreductase chaperones from thioredoxin superfamily. As redox folding catalysts from the endoplasmic reticulum (ER), their roles in ER-related redox homeostasis and signaling are well-studied. PDIA1 exerts thiol oxidation/reduction and isomerization, plus chaperone effects. Also, substantial evidence indicates that PDIs regulate thiol-disulfide switches in other cell locations such as cell surface and possibly cytosol. Subcellular PDI translocation routes remain unclear and seem Golgi-independent. The list of signaling and structural proteins reportedly regulated by PDIs keeps growing, via thiol switches involving oxidation, reduction and isomerization, S-(de)nytrosylation, (de)glutathyonylation and protein oligomerization. PDIA1 is required for agonist-triggered Nox NADPH oxidase activation and cell migration in vascular cells and macrophages, while PDIA1-dependent cytoskeletal regulation appears a converging pathway. Extracellularly, PDIs crucially regulate thiol redox signaling of thrombosis/platelet activation, e.g., integrins, and PDIA1 supports expansive caliber remodeling during injury repair via matrix/cytoskeletal organization. Some proteins display regulatory PDI-like motifs. PDI effects are orchestrated by expression levels or post-translational modifications. PDI is redox-sensitive, although probably not a mass-effect redox sensor due to kinetic constraints. Rather, the "all-in-one" organization of its peculiar redox/chaperone properties likely provide PDIs with precision and versatility in redox signaling, making them promising therapeutic targets.

MiR-573 inhibits prostate cancer metastasis by regulating epithelial-mesenchymal transition

The metastastic cascade is a complex process that is regulated at multiple levels in prostate cancer (PCa). Recent evidence suggests that microRNAs (miRNAs) are involved in PCa metastasis and hold great promise as therapeutic targets. In this study, we found that miR-573 expression is significantly lower in metastatic tissues than matched primary PCa. Its downregulation is correlated with high Gleason score and cancer-related mortality of PCa patients (P = 0.041, Kaplan-Meier analysis). Through gain- and loss-of function experiments, we demonstrated that miR-573 inhibits PCa cell migration, invasion and TGF-β1-induced epithelial-mesenchymal transition (EMT) in vitro and lung metastasis in vivo. Mechanistically, miR573 directly targets the fibroblast growth factor receptor 1 (FGFR1) gene. Knockdown of FGFR1 phenocopies the effects of miR-573 expression on PCa cell invasion, whereas overexpression of FGFR1 partially attenuates the functions of miR-573. Consequently, miR-573 modulates the activation of FGFR1-downstream signaling in response to fibroblast growth factor 2 (FGF2). Importantly, we showed that GATA3 directly increases miR-573 expression, and thus down-regulates FGFR1 expression, EMT and invasion of PCa cells in a miR-573-dependent manner, supporting the involvement of GATA3, miR-573 and FGFR1 in controlling the EMT process during PCa metastasis. Altogether, our findings demonstrate a novel mechanism by which miR-573 modulates EMT and metastasis of PCa cells, and suggest miR-573 as a potential biomarker and/or therapeutic target for PCa management.

High TXNDC5 expression predicts poor prognosis in renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common primary kidney cancer in adults, and the identification of biomarkers involved in the pathogenesis and prognosis of ccRCC is crucial for early diagnosis and anticancer treatment. In this study, we demonstrate that thioredoxin domain-containing protein 5 (TXNDC5) expression is markedly upregulated in ccRCC tissues in comparison with adjacent non-cancerous tissues through quantitative RT-PCR, Western blotting, and immunohistochemical analyses. Importantly, TXNDC5 expression is negatively correlated with the overall survival of patients. Knockdown of TXNDC5 by siRNAs inhibits the cell growth, migration, and invasion of ccRCC cells as well as sensitizes ccRCC cells to chemotherapeutic drugs, such as Camptothecin and 5-Fluorouracil. Moreover, we used complementary DNA (cDNA) microarray analyses to explore the underlying molecular mechanisms of TXNDC5 in the pathogenesis of ccRCC. We demonstrate that knockdown of TXNDC5 affects the messenger RNA (mRNA) and protein levels of numerous important genes associated with tumorigenesis. In summary, our findings indicate that TXNDC5 performs an essential function in ccRCC pathogenesis and can serve as a novel prognostic marker of ccRCC.

Enhanced photoelectrochemical aptasensing platform for TXNDC5 gene based on exciton energy transfer between NCQDs and TiO2 nanorods

The over expression of thioredoxin domain-containing protein 5 (TXNDC5) can promote the growth of castration-resistant prostate cancer (CRPC). A novel highly sensitive photoelectrochemical (PEC) aptsensor was developed for the detection of TXNDC5 by using the nanohybrids (TiO₂ NRs/NCQDs) of nitrogen-doped carbon quantum dots (NCQDs) and TiO₂ nanorods as the photo-to-electron conversion medium. TiO₂ NRs/NCQDs nanohybrids were prepared by controlling the experimental condition. TiO₂ NRs were self-assembled to form the nanopores with good photocurrent conversion efficiency. NCQDs possessed carboxyl groups (−COOH) and amino groups (−NH₂) in the preparation process. −COOH and −NH₂ groups played important roles for anchoring the capture probes (5′ primer and 3′ primer) through covalent binding. The ultrasensitive and stable detection for TXNDC5 was achieved by the specific recognition between the capture probes and the targets. The fabricated aptsensor showed excellent performance with a wide linear range (0.5 fmol/L ∼ 10 nmol/L) and a low detection limit of 0.1 fmol/L. This kind of aptsensor would provide a potential application for TXNDC5.

Biomarker Development for Intraductal Papillary Mucinous Neoplasms Using Multiple Reaction Monitoring Mass Spectrometry

Intraductal papillary mucinous neoplasm (IPMN) is a common precursor of pancreatic cancer (PC). Much clinical attention has been directed toward IPMNs due to the increase in the prevalence of PC. The diagnosis of IPMN depends primarily on a radiological examination, but the diagnostic accuracy of this tool is not satisfactory, necessitating the development of accurate diagnostic biomarkers for IPMN to prevent PC. Recently, high-throughput targeted proteomic quantification methods have accelerated the discovery of biomarkers, rendering them powerful platforms for the evolution of IPMN diagnostic biomarkers. In this study, a robust multiple reaction monitoring (MRM) pipeline was applied to discovery and verify IPMN biomarker candidates in a large cohort of plasma samples. Through highly reproducible MRM assays and a stringent statistical analysis, 11 proteins were selected as IPMN marker candidates with high confidence in 184 plasma samples, comprising a training (n = 84) and test set (n = 100). To improve the discriminatory power, we constructed a six-protein panel by combining marker candidates. The multimarker panel had high discriminatory power in distinguishing between IPMN and controls, including other benign diseases. Consequently, the diagnostic accuracy of IPMN can be improved dramatically with this novel plasma-based panel in combination with a radiological examination.