A circRNA-miRNA-mRNA network analysis underlying pathogenesis of human heart failure.

BACKGROUND: The molecular mechanisms of heart failure (HF) are still poorly understood. Circular RNA (circRNA) has been discovered in the heart in increasing numbers of studies. The goal of this research is to learn more about the potential roles of circRNAs in HF. METHODS & RESULTS: We used RNA sequencing data to identify the characteristics of circRNAs expressed in the heart and discovered that the majority of circRNAs screened were less than 2000 nt. Additionally, chromosomes One and Y had the most and least number of circRNAs, respectively. After excluding duplicate host genes and intergenic circRNAs, a total of 238 differentially expressed circRNAs (DECs) and 203 host genes were discovered. However, only four of the 203 host genes of DECs were examined in HF differentially expressed genes. Another study used Gene Oncology analysis of DECs host genes to elucidate the underlying pathogenesis of HF, and it found that binding and catalytic activity accounted for a large portion of DECs. Immune system, metabolism, and signal transduction pathways were significantly enriched. Furthermore, 1052 potentially regulated miRNAs from the top 40 DECs were collected to build a circRNA-miRNA network, and it was discovered that 470 miRNAs can be regulated by multiple circRNAs, while others are regulated by a single circRNA. In addition, a comparison of the top 10 mRNAs in HF and their targeted miRNAs revealed that DDX3Y and UTY were regulated by the most and least circRNA, respectively. CONCLUSION: These findings demonstrated circRNAs have species and tissue specific expression patterns; while circRNA expression is independent on host genes, the same types of genes in DECs and DEGs worked in HF. Our findings would contribute to a better understanding of the critical roles of circRNAs and lay the groundwork for future studies of HF molecular functions.

Insights into peptide profiling of sturgeon myofibrillar proteins with low temperature vacuum heating.

BACKGROUND: Protein oxidation during food processing causes changes in the balance of protein-molecular interactions and protein-water interactions, ultimately leading to protein denaturation, which results in the loss of a range of functional properties. Therefore, how to control the oxidative modification of proteins during processing has been the focus of research. RESULTS: In the present study, the intrinsic fluorescence value of the myofibrillar proteins (MP) decreased and the surface hydrophobicity value increased, indicating that the heat treatment caused a significant change in the conformation of the MP. With an increase in heating temperature, protein carbonyl content increased, total sulfhydryl content decreased, and protein secondary structure changed from α-helix to ß-sheet, indicating that protein oxidation and aggregation occurred. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that heat treatment can lead to the degradation of proteins, especially myosin heavy chain, although actin had a certain thermal stability. In total, 733 proteins were identified by proteomics, and the protein oxidation caused by low temperature vacuum heating (LTVH) was determined to be mild oxidation dominated by malondialdehyde and 4-hydroxynonenal by oxidation site division. CONCLUSION: The present study has revealed the effect of LTVH treatment on the protein oxidation modification behavior of sturgeon meat, and explored the effect mechanism of LTVH treatment on the processing quality of sturgeon meat from the perspective of protein oxidation. The results may provide a theoretical basis for the precise processing of aquatic products. © 2023 Society of Chemical Industry.

PTEN Deficiency Facilitates Exosome Secretion and Metastasis in Cholangiocarcinoma by Impairing TFEB-mediated Lysosome Biogenesis.

BACKGROUND & AIMS: In eukaryotes, the ubiquitin-proteasome system and the autophagy-lysosome pathway are essential for maintaining cellular proteostasis and associated with cancer progression. Our previous studies have demonstrated that phosphatase and tensin homolog (PTEN), one of the most frequently mutated genes in human cancers, limits proteasome abundance and determines chemosensitivity to proteasome inhibitors in cholangiocarcinoma (CCA). However, whether PTEN regulates the lysosome pathway remains unclear. METHODS: We tested the effects of PTEN on lysosome biogenesis and exosome secretion using loss- and gain-of-function strategies in CCA cell lines. Using in vitro dephosphorylation assays, we explored the regulatory mechanism between PTEN and the key regulator of lysosome biogenesis, transcription factor EB (TFEB). Using the migration assays, invasion assays, and trans-splenic liver metastasis mouse models, we evaluated the function of PTEN deficiency, TFEB-mediated lysosome biogenesis, and exosome secretion on tumor metastasis. Moreover, we investigated the clinical significance of PTEN expression and exosome secretion by retrospective analysis. RESULTS: PTEN facilitated lysosome biogenesis and acidification through its protein phosphatase activity to dephosphorylate TFEB at Ser211. Notably, PTEN deficiency increased exosome secretion by reducing lysosome-mediated degradation of multi-vesicular bodies, which further facilitated the proliferation and invasion of CCA. TFEB agonist curcumin analog C1 restrained the metastatic phenotype caused by PTEN deficiency in mouse models, and we highlighted the correlation between PTEN deficiency and exosome secretion in clinical cohorts. CONCLUSIONS: In CCA, PTEN deficiency impairs lysosome biogenesis to facilitate exosome secretion and cancer metastasis in a TFEB phosphorylation-dependent manner.

Interaction and binding mechanism of lipid oxidation products to sturgeon myofibrillar protein in low temperature vacuum heating conditions: Multispectroscopic and molecular docking approaches.

In this work, the binding mechanism of myofibrillar protein (MP) with malondialdehyde and 4-hydroxy-2-nonenal under low temperature vacuum heating was investigated via multispectroscopic and molecular docking. The results showed that binding interaction and increasing temperature caused significant changes in the conformations as well as a decrease in the value of protein intrinsic fluorescence, surface hydrophobicity, and fluorescence excitation-emission matrix spectra. Furthermore, the decrease in α-helix and ß-turn, increase in ß-sheet and a random coil of MP, imply the MP molecules to be more unfolded. Isothermal titration calorimetry and molecular docking results showed that main driving force for binding with MP was hydrogen bond, and the binding ability of malondialdehyde was superior to that of 4-hydroxy-2-nonenal. Moreover, increasing the heating temperature was beneficial to the binding reaction and intensified the conformational transition of MP. These results will provide a reference for further studies on the lipid and protein interaction of sturgeon.

Gankyrin and TIGAR cooperatively accelerate glucose metabolism toward the PPP and TCA cycle in hepatocellular carcinoma.

Oncogene-derived metabolic reprogramming is important for anabolic growth of cancer cells, which is now considered to be not simply rely on glycolysis. Pentose phosphate pathway and tricarboxylic acid cycle also play pivotal roles in helping cancer cells to meet their anabolic and energy demands. The present work focused on gankyrin, a relatively specific oncogene in hepatocellular carcinoma (HCC), and its impact on glycolysis and mitochondrial homeostasis. Metabolomics, RNA-seq analysis, and subsequent conjoint analysis illustrated that gankyrin regulated the pentose phosphate pathway (PPP), tricarboxylic acid (TCA) cycle, and mitochondrial function and homeostasis, which play pivotal roles in tumor development. Mechanistically, gankyrin was found to modulate HCC metabolic reprogramming via TIGAR. Gankyrin positively regulated the transcription of TIGAR through Nrf2, which bound to the antioxidant response elements (AREs) in the promoter of TIGAR. Interestingly, TIGAR feedback regulated the transcription of Nrf2 and subsequently gankyrin by promoting nuclear importation of PGC1α. The loop between gankyrin, Nrf2, and TIGAR accelerated glucose metabolism toward the PPP and TCA cycle, which provided vital building blocks, such as NADPH, ATP, and ribose of tumor and further facilitated the progression of HCC.

Monitoring the lipid oxidation and flavor of Russian sturgeon fillets treated with low temperature vacuum heating: formation and relationship.

BACKGROUND: Sturgeon is one of the most precious fish resources worldwide. Low temperature vacuum heating (LTVH) has been confirmed as a good way of maintaining food quality. However, there is a lack of in-depth studies assessing the impact of LTVH on lipid oxidation and flavor formation. RESULTS: The present study compared the effect of LTVH and traditional cooking on lipid oxidation and flavor of sturgeon fillets. In total, 13 fatty acids were detected, of which polyunsaturated fatty acids content was the highest (P < 0.05). LTVH prevented the formation of conjugated diene and thiobarbituric acid reactive substances (P < 0.05), as manifested by an increased signal intensity of free radicals of electron spin resonance. The characteristic peaks intensity of lipid by Raman at 970 cm-1 , 1080 cm-1 and 1655 cm-1 were reduced, whereas peaks at 1068 cm-1 and 1125 cm-1 displayed the opposite trend. Confocal fluorescence microscopy showed that the lipids particles were reduced and distributed more evenly with an increase in heating temperature. Principal component analysis of electronic nose cannot effectively separate all groups; however, gas chromatography-ion migration spectrometry showed that the volatile flavor compounds were relatively stable during LTVH. Correlation analysis of all the above lipid oxidation indices and characteristic flavor substances showed that each treatment group was located in different quadrants and demonstrated great differentiation. CONCLUSION: Overall, the results of the present study support the view that LTVH is a healthier way of cooking. © 2022 Society of Chemical Industry.

Deduction and exploration of the evolution and function of vertebrate GFPT family.

BACKGROUND: Glutamine-fructose-6-phosphate aminotransferase (GFPT) is a key factor in the hexosamine metabolism pathway. It regulates the downstream factor O-GlcNAc to change cell function and plays an important role in the metabolism and immune process of tissues and organs. However, the evolutionary relationship of GFPT family proteins in vertebrates has not been elucidated. OBJECTIVE: To deduce and explore the evolution and function of vertebrate GFPT family. METHODS: 18 GFPT sequences were obtained from Homo sapiens (H. sapiens), Trachypithecus francoisi (T. francoisi), Mus musculus (M. musculus), Rattus norvegicus (R. norvegicus), Gallus gallus (G. gallus), Zootoca vivipara (Z. vivipara), Xenopus tropicalis (X. tropicalis), Danio rerio (D. rerio), Rhincodon typus (R. typus), Plasmodium relictum from National Center for Biotechnology Information (NCBI). The physical and chemical characteristics and molecular evolution of GFPT family proteins and nucleic acid sequences were analyzed by ClustalX2, Gene Doc, MEGA-X, SMART, Datamonkey, R etc. RESULTS: Based on the neighbor-joining (NJ) phylogenetic tree and evolution fingerprints, GFPT family members of vertebrates can be divided into two groups: the GFPT1 group and the GFPT2 group. Seven positive selection sites were identified by IFEL and integrated methods mixed effects model of evolution (MEME) and fixed effects likelihood (REL). Finally, we predicted 28 phosphorylation sites and 18 ubiquitousness sites in the human GFPT1 sequence, 10 phosphorylation sites, and five ubiquitousness sites in GFPT2. Gene ontology (GO) analyzes the protein molecules and KEGG signaling pathways of vertebrates interacting with GFPT family proteins. CONCLUSIONS: Our work confirmed that higher animals GFPT family may have differentiated GFPT1 and GFPT2, which meets their own functional needs. This knowledge answers the question what the origin and evolution of GFPT family in vertebrates and provided the basis for disease treatment and function research of GFPT protein.

Quantitative proteomics reveals the relationship between protein changes and off-flavor in Russian sturgeon (Acipenser gueldenstaedti) fillets treated with low temperature vacuum heating.

This study aimed to reveal the molecular mechanisms associated with off-flavor generation in sturgeon fillets treated by low temperature vacuum heating (LTVH). Label-free quantitative proteomics was used to identify 120 favor-related proteins, 27 proteins were screened as differentially expressed for bioinformatics analysis. 17 of KEGG pathways were identified. Particularly, proteins involved in proteasome and peroxisome were highly correlated with off-flavor formation. They were primarily implicated in the structures of proteins, including binding and proteasome pathways. The results indicated that the LTVH reduced the binding sites by down-regulating protease and superoxide dismutase expression. LTVH increased the myofibrillar protein and sulfhydryl content and decreased the total volatile basic nitrogen and thiobarbituric acid reactive substance, which confirmed that protein oxidation was related to off-flavor. This proteomics study provided new insights into the off-flavor of sturgeon with LTVH, and proposed potential link between biological processes and off-flavor formation.

A predictive and prognostic model for hepatocellular carcinoma with microvascular invasion based TCGA database genomics.

BACKGROUND: Microvascular invasion (MVI) adversely affects postoperative long-term survival outcomes in patients with hepatocellular carcinoma (HCC). There is no study addressing genetic changes in HCC patients with MVI. We first screened differentially expressed genes (DEGs) in patients with and without MVI based on TCGA data, established a prediction model and explored the prognostic value of DEGs for HCC patients with MVI. METHODS: In this paper, gene expression and clinical data of liver cancer patients were downloaded from the TCGA database. The DEG analysis was conducted using DESeq2. Using the least absolute shrinkage and selection operator, MVI-status-related genes were identified. A Kaplan-Meier survival analysis was performed using these genes. Finally, we validated two genes, HOXD9 and HOXD10, using two sets of HCC tissue microarrays from 260 patients. RESULTS: Twenty-three MVI-status-related key genes were identified. Based on the key genes, we built a classification model using random forest and time-dependent receiver operating characteristic (ROC), which reached 0.814. Then, we performed a survival analysis and found ten genes had a significant difference in survival time. Simultaneously, using two sets of 260 patients' HCC tissue microarrays, we validated two key genes, HOXD9 and HOXD10. Our study indicated that HOXD9 and HOXD10 were overexpressed in HCC patients with MVI compared with patients without MVI, and patients with MVI with HOXD9 and 10 overexpression had a poorer prognosis than patients with MVI with low expression of HOXD9 and 10. CONCLUSION: We established an accurate TCGA database-based genomics prediction model for preoperative MVI risk and studied the prognostic value of DEGs for HCC patients with MVI. These DEGs that are related to MVI warrant further study regarding the occurrence and development of MVI.

Hypertrophic preconditioning cardioprotection after myocardial ischaemia/reperfusion injury involves ALDH2-dependent metabolism modulation.

Brief episodes of ischaemia and reperfusion render the heart resistant to subsequent prolonged ischaemic insult, termed ischaemic preconditioning. Here, we hypothesized that transient non-ischaemic stress by hypertrophic stimulation would induce endogenous cardioprotective signalling and enhance cardiac resistance to subsequent ischaemic damage. Transient transverse aortic constriction (TAC) or Ang-Ⅱ treatment was performed for 3-7 days in male mice and then withdrawn for several days by either aortic debanding or discontinuing Ang-Ⅱ treatment, followed by subsequent exposure to regional myocardial ischaemia by in situ coronary artery ligation. Following ischaemia/reperfusion (I/R) injury, myocardial infarct size and apoptosis were markedly reduced and contractile function was significantly improved in the TAC preconditioning group compared with that in the control group. Similar results were observed in mice receiving Ang-Ⅱ infusion. Mechanistically, TAC preconditioning enhanced ALDH2 activity, promoted AMPK activation and improved mitochondrial energy metabolism by increasing myocardial OXPHOS complex expression, elevating the mitochondrial ATP content and improving viable myocardium glucose uptake. Moreover, TAC preconditioning significantly mitigated I/R-induced myocardial iNOS/gp91phox activation, inhibited endoplasmic reticulum stress and ameliorated mitochondrial impairment. Using a pharmacological approach to inhibit AMPK signalling in the presence or absence of preconditioning, we demonstrated AMPK-dependent protective mechanisms of TAC preconditioning against I/R injury. Furthermore, treatment with adenovirus-encoded ALDH2 partially emulated the actions of hypertrophic preconditioning, as evidenced by improved mitochondrial metabolism, inhibited oxidative stress-induced mitochondrial damage and attenuated cell death through an AMPK-dependent mechanism, whereas genetic ablation of ALDH2 abrogated the aforementioned actions of TAC preconditioning. The present study demonstrates that preconditioning with hypertrophic stress protects the heart from I/R injury via mechanisms that improve mitochondrial metabolism, reduce oxidative/nitrative stress and inhibit apoptosis. ALDH2 is obligatorily required for the development of cardiac hypertrophic preconditioning and acts as the mediator of this process.

COCH predicts survival and adjuvant TACE response in patients with HCC.

The aim of the present study was to measure the expression of Cochlin (COCH) and analyze its association with survival, recurrence and the benefits from adjuvant transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC) following hepatectomy. Patients with high COCH expression levels had a poorer prognosis in terms of overall and disease-free survival rate compared with those with low COCH expression levels. Further analysis revealed that patients with low COCH expression who received TACE experienced markedly lower early recurrence rates compared with those who did not receive TACE. However, patients with high COCH expression with and without adjuvant TACE after resection experienced no difference in disease recurrence rates. The expression of COCH was found to be associated with hepatitis B virus infection, portal vein tumor thrombosis and Barcelona Clinic Liver Cancer stage in HCC. Therefore, the findings of the present study indicated that clinical detection of COCH expression may help estimate the prognosis of patients with HCC, as well as determine whether to administer TACE after surgery to prevent recurrence.

PTEN deficiency facilitates the therapeutic vulnerability to proteasome inhibitor bortezomib in gallbladder cancer.

Gallbladder cancer (GBC) is an aggressive malignancy of biliary tract with poor prognosis. Although several studies have shown the frequency of relevant genetic alterations, there are few genetic models or translational studies that really benefit for GBC treatment in the era of precision medicine. By targeted sequencing and immunohistochemistry staining, we identified that phosphate and tension homology deleted on chromosome ten (PTEN) was frequently altered in GBC specimens, and loss of PTEN expression was independently correlated with poor survival outcomes. Further drug screening assays revealed proteasome inhibitor bortezomib as a promising agent for GBC treatment, and knockdown of PTEN increased bortezomib efficacy both in vivo and in vitro. Therapeutic evaluation of patient derived xenografts (PDXs) strongly supported the utilization of bortezomib in PTEN deficient GBC. Mechanically, functional PTEN inhibited ARE-dependent transcriptional activity, the same machinery regulating the transcription of proteasome subunits, thus PTEN suppressed proteasome activity and bortezomib sensitivity. Through siRNA screening, we identified the ARE-related transcriptional suppressor BACH1 involved in PTEN-mediated proteasome inhibition and regulated by PTEN-AKT1 axis. In summary, our study indicates that proteasome activity represents a prime therapeutic target in PTEN-deficient GBC tumors, which is worthy of further clinical validation.

RPB5-Mediating Protein Promotes Cholangiocarcinoma Tumorigenesis and Drug Resistance by Competing With NRF2 for KEAP1 Binding.

BACKGROUND AND AIMS: Cancer cell survival depends on the balance between reactive oxygen species production and scavenging, which is regulated primarily by NRF2 during tumorigenesis. Here, we demonstrate that deletion of RBP5-mediating protein (RMP) in an autonomous mouse model of intrahepatic cholangiocarcinoma (ICC) delays tumor progression. APPROACH AND RESULTS: RMP-overexpressing tumor cells exhibited enhanced tolerance to oxidative stress and apoptosis. Mechanistically, RMP competes with NRF2 for binding to the Kelch domain of KEAP1 (Kelch-like ECH-associated protein 1) through the E**E motif, leading to decreased NRF2 degradation via ubiquitination, thus increasing NRF2 nuclear translocation and downstream transactivation of antioxidant genes. This RMP-KEAP1-NRF2 axis promotes ICC tumorigenesis, metastasis, and drug resistance. Consistent with these findings, the RMP level in human ICC is positively correlated with the protein level of NRF2 and is associated with poor prognosis. CONCLUSION: These findings reveal that RMP is involved in the oxidative stress defense program and could be exploited for targeted cancer therapies.

CircularRNA_104670 plays a critical role in intervertebral disc degeneration by functioning as a ceRNA.

This study was carried out to explore the roles of circular RNAs (circRNAs) in nucleus pulposus (NP) tissues in intervertebral disc degeneration (IDD). Differentially expressed circRNAs in IDD and normal NP tissues were identified based on the results of microarray analysis. Bioinformatics techniques were employed to predict the direct interactions of selected circRNAs, microRNAs (miR), and mRNAs. CircRNA_104670 was selected as the target circRNA due to its large multiplier expression in IDD tissues. After luciferase reporter and EGFP/RFP reporter assays, we confirmed that circRNA_104670 directly bound to miR-17-3p, while MMP-2 was the direct target of miR-17-3p. The receiver-operating characteristic (ROC) curve showed that circRNA_104670 and miR-17-3p had good diagnostic significance for IDD (AUC circRNA_104670 = 0.96; AUC miRNA-17-3p = 0.91). A significant correlation was detected between the Pfirrmann grade and expression of circRNA_104670 (r = 0.63; p = 0.00) and miR-17-3p (r = -0.62; p = 0.00). Flow-cytometric analysis and the MTT assay showed that interfering with circRNA_104670 using small interfering RNA (siRNA) inhibited NP cell apoptosis (p < 0.01), and this inhibition was reduced by interfering with miR-17-3p. Interfering with circRNA_104670 suppressed MMP-2 expression and increased extracellular matrix (ECM) formation, which were also reduced by interfering with miR-17-3p. Finally, an MRI evaluation showed that circRNA_104670 inhibition mice had a lower IDD grade compared with control mice (p < 0.01), whereas circRNA_104670 and miRNA-17-3p inhibition mice had a higher IDD grade compared with circRNA_104670 inhibition mice (p < 0.05). CircRNA_104670 is highly expressed in the NP tissues of IDD and acts as a ceRNA during NP degradation.

Alginate Oligosaccharide Prevents Acute Doxorubicin Cardiotoxicity by Suppressing Oxidative Stress and Endoplasmic Reticulum-Mediated Apoptosis.

Doxorubicin (DOX) is a highly potent chemotherapeutic agent, but its usage is limited by dose-dependent cardiotoxicity. DOX-induced cardiotoxicity involves increased oxidative stress and activated endoplasmic reticulum-mediated apoptosis. Alginate oligosaccharide (AOS) is a non-immunogenic, non-toxic and biodegradable polymer, with anti-oxidative, anti-inflammatory and anti-endoplasmic reticulum stress properties. The present study examined whether AOS pretreatment could protect against acute DOX cardiotoxicity, and the underlying mechanisms focused on oxidative stress and endoplasmic reticulum-mediated apoptosis. We found that AOS pretreatment markedly increased the survival rate of mice insulted with DOX, improved DOX-induced cardiac dysfunction and attenuated DOX-induced myocardial apoptosis. AOS pretreatment mitigated DOX-induced cardiac oxidative stress, as shown by the decreased expressions of gp91 (phox) and 4-hydroxynonenal (4-HNE). Moreover, AOS pretreatment significantly decreased the expression of Caspase-12, C/EBP homologous protein (CHOP) (markers for endoplasmic reticulum-mediated apoptosis) and Bax (a downstream molecule of CHOP), while up-regulating the expression of anti-apoptotic protein Bcl-2. Taken together, these findings identify AOS as a potent compound that prevents acute DOX cardiotoxicity, at least in part, by suppression of oxidative stress and endoplasmic reticulum-mediated apoptosis.

Gankyrin has an antioxidative role through the feedback regulation of Nrf2 in hepatocellular carcinoma.

Oxidative stress status has a key role in hepatocellular carcinoma (HCC) development and progression. Normally, reactive oxygen species (ROS) levels are tightly controlled by an inducible antioxidant program that responds to cellular stressors. How HCC cells respond to excessive oxidative stress remains elusive. Here, we identified a feedback loop between gankyrin, an oncoprotein overexpressed in human HCC, and Nrf2 maintaining the homeostasis in HCC cells. Mechanistically, gankyrin was found to interact with the Kelch domain of Keap1 and effectively competed with Nrf2 for Keap1 binding. Increased expression of gankyrin in HCC cells blocked the binding between Nrf2 and Keap1, inhibiting the degradation of Nrf2 by proteasome. Interestingly, accumulation and translocation of Nrf2 increased the transcription of gankyrin through binding to the ARE elements in the promoter of gankyrin. The positive feedback regulation involving gankyrin and Nrf2 modulates a series of antioxidant enzymes, thereby lowering intracellular ROS and conferring a steadier intracellular environment, which prevents mitochondrial damage and cell death induced by excessive oxidative stress. Our results indicate that gankyrin is a regulator of cellular redox homeostasis and provide a link between oxidative stress and the development of HCC.

RMP predicts survival and adjuvant TACE response in hepatocellular carcinoma.

Adjuvant transcatheter arterial chemoembolization (TACE) protects against hepatocellular carcinoma (HCC) and is associated with reduced disease recurrence and improved outcome after surgery. However, deterioration of liver function after TACE negatively impacts the patient prognosis and limits it use as an option to prolong survival. We analyzed two independent cohorts that included a total of 510 patients with HCC who had undergone tumor resection. Immunohistochemistry assay was used to measure RPB5-mediating protein (RMP) expression and assessed their association with recurrence rate and response to therapy with adjuvant TACE. In patients with HCC, the expression of RMP in tumor is associated with age, gender, tumor size, portal venous invasion, TNM stages, BCLC stages and overall survival. Among patients with high RMP expression, adjuvant TACE after resection was associated with early recurrence. Even in the patients with small tumor size (no more than 5 cm) or no venous invasion, RMP status is associated with response to adjuvant TACE. RMP status in tumors may be a useful marker in estimating prognosis in patients with HCC and in assisting in the selection of patients who are likely to benefit from adjuvant TACE to prevent relapse.

CKAP4 inhibited growth and metastasis of hepatocellular carcinoma through regulating EGFR signaling.

CKAP4, one kind of type II trans-membrane protein, plays an important role to maintain endoplasmic reticulum structure and inhibits the proliferation of bladder cancer cells by combining its ligand anti-proliferative factor (APF). However, the biological function of CKAP4 in the progression of liver cancer has not been clearly demonstrated. In the present study, we knocked down or overexpressed CKAP4 in hepatocellular carcinoma (HCC) cells and cell proliferation, invasion, and migration capacities were investigated by CCK-8 and transwell assays. In vivo tumor model in mice was used to evaluate the role of CKAP4 on growth and metastasis of HCC. The data documented that HCC cells with high CKAP4 levels were featured by low proliferation capability as well as low invasion potential. Interestingly, we found that CKAP4 suppressed the activation of epithelial growth factor receptor (EGFR) signaling, which may partly explain the role of CKAP4 in cell biological behavior of HCC. Further study revealed that CKAP4 could associate with EGFR at basal status and the complex was reduced upon EGF stimulation, leading to release EGFR into cytoplasm. Thus, we demonstrate the novel mechanism, for the first time, expression of CKAP4 regulates progression and metastasis of HCC and it may provide therapeutic values in this tumor.

Prognostic significance of cytoskeleton-associated membrane protein 4 and its palmitoyl acyltransferase DHHC2 in hepatocellular carcinoma.

BACKGROUND: The functions of cytoskeleton-associated membrane protein 4 (CKAP4), one kind of type II transmembrane protein, are associated with the palmitoyl acyltransferase DHHC2. The objective of the current study was to investigate CKAP4/DHHC2 expression and its prognostic significance in patients with hepatocellular carcinoma (HCC). METHODS: Two independent cohorts of 416 patients with HCC were enrolled. All the patients included had defined clinicopathologic and follow-up data. Using real-time polymerase chain reaction and immunohistochemical assay, CKAP4 and DHHC2 expression were evaluated. The association between CKAP4/DHHC2 expression and HCC-specific disease-free survival and overall survival was analyzed by Kaplan-Meier curves, the log-rank test, and Multivariate Cox regression analyses. RESULTS: The data documented that CKAP4 expression was much higher in HCC tumor tissues compared with adjacent normal tissues and its expression was significantly correlated with tumor size, intrahepatic metastases, portal venous invasion, and Barcelona Clinic Liver Cancer stage of disease in 2 cohorts of patients. On survival analysis, patients with high CKAP4 expression appeared to have a favorable overall survival and a longer disease-free survival compared with those with low expression. DHHC2 expression was also examined in tissue microarray analysis by immunohistochemistry and the results demonstrated that 87.6% of the cases had low expression of DHHC2. Kaplan-Meier analysis indicated that a high level of DHHC2 expression predicted favorable overall survival and disease-free survival rates in both the training cohort and validation set. Furthermore, the combination of CKAP4 and DHHC2 was found to have a more powerful efficiency in prognosis prediction than either one alone. CONCLUSIONS: To the best of our knowledge, the current study is the first to demonstrate that the expression of CKAP4 and its palmitoyl acyltransferase DHHC2 correlates with disease progression and metastasis in patients with HCC and may provide prognostic and therapeutic value.

Signal regulatory protein α is associated with tumor-polarized macrophages phenotype switch and plays a pivotal role in tumor progression.

UNLABELLED: Macrophages (Mψ) are the major component of infiltrating leukocytes in tumors and exhibit distinct phenotypes according to the microenvironment. We have recently found that signal regulatory protein α (SIRPα), the inhibitory molecule expressed on myeloid cells, plays a critical role in controlling innate immune activation. Here, we identify that SIRPα is down-regulated on monocytes/Mψ isolated from peritumoral areas of hepatocellular carcinoma (HCC) samples, while its level is moderately recovered in intratumor Mψ. In vitro assays demonstrate that SIRPα expression is significantly reduced on Mψ when cocultured with hepatoma cells. This reduction is partly due to the soluble factors in the tumor microenvironment. Knockdown (KD) of SIRPα prolongs activation of nuclear factor kappa B (NF-κB) and PI3K-Akt pathways as Mψ encounter tumor cells, leading to an increased capacity of Mψ for migration, survival, and proinflammatory cytokine production. Enhanced Stat3 and impaired Stat1 phosphorylation are also observed in tumor-exposed SIRPα-KD Mψ. Adoptive transfer with SIRPα-KD Mψ accelerates mouse hepatoma cells growth in vivo by remolding the inflammatory microenvironment and promoting angiogenesis. SIRPα accomplishes this partly through its sequestration of the signal transducer Src homology 2-containing phosphotyrosine phosphatase (SHP2) from IκB kinase ß (IKKß) and PI3K regulatory subunit p85 (PI3Kp85). CONCLUSION: These findings suggest that SIRPα functions as an important modulator of tumor-polarized Mψ in hepatoma, and the reduction of SIRPα is a novel strategy used by tumor cells to benefit their behavior. Therefore, SIRPα could be utilized as a potential target for HCC therapy.