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Background: Regulatory T cells (Tregs) play a critical role in shaping the immunosuppressive microenvironment within tumors. Investigating the role of Tregs in Clear cell renal cell carcinoma (ccRCC) is crucial for identifying prognostic markers and therapeutic targets for ccRCC. Methods: Weighted gene co-expression network analysis (WGCNA) was utilized to pinpoint modules related to Treg infiltration in TCGA-KIRC samples. Following this, consensus clustering was employed to derive two clusters associated with Treg infiltration in ccRCC. A prognostic model was then developed using the gene module associated with Treg infiltration. We then evaluated the ability of the prognostic model to predict ccRCC overall survival and demonstrated that RCN1 can be used as a target to predict ccRCC prognosis. Results: We deduce that the two clusters associated with Treg infiltration exhibit distinct compositions of the immune microenvironment, pathway activations, prognosis, and drug sensitivities commonly utilized in ccRCC treatment. Furthermore, a 7-gene model risk score, developed based on ccRCC Treg infiltration, proved to be a reliable prognostic marker in both training and validation cohorts. Additionally, survival analysis indicated that RCN1 serves as a reliable prognostic factor for ccRCC. Single-cell sequencing analysis revealed that RCN1 is predominantly expressed in tumor cells. A pan-cancer analysis highlighted that RCN1 is linked with poor prognosis and the activation of inflammatory response pathways across various cancers. Conclusion: We developed a prognostic model associated with Treg infiltration, which facilitates the clinical categorization of ccRCC progression. Moreover, our findings underscore the significant potential of RCN1 as a ccRCC biomarker. [ABSTRACT FROM AUTHOR]

Abstract Background Regulatory T cells (Tregs) play a critical role in shaping the immunosuppressive microenvironment within tumors. Investigating the role of Tregs in Clear cell renal cell carcinoma (ccRCC) is crucial for identifying prognostic markers and therapeutic targets for ccRCC. Methods Weighted gene co-expression network analysis (WGCNA) was utilized to pinpoint modules related to Treg infiltration in TCGA-KIRC samples. Following this, consensus clustering was employed to derive two clusters associated with Treg infiltration in ccRCC. A prognostic model was then developed using the gene module associated with Treg infiltration. We then evaluated the ability of the prognostic model to predict ccRCC overall survival and demonstrated that RCN1 can be used as a target to predict ccRCC prognosis. Results We deduce that the two clusters associated with Treg infiltration exhibit distinct compositions of the immune microenvironment, pathway activations, prognosis, and drug sensitivities commonly utilized in ccRCC treatment. Furthermore, a 7-gene model risk score, developed based on ccRCC Treg infiltration, proved to be a reliable prognostic marker in both training and validation cohorts. Additionally, survival analysis indicated that RCN1 serves as a reliable prognostic factor for ccRCC. Single-cell sequencing analysis revealed that RCN1 is predominantly expressed in tumor cells. A pan-cancer analysis highlighted that RCN1 is linked with poor prognosis and the activation of inflammatory response pathways across various cancers. Conclusion We developed a prognostic model associated with Treg infiltration, which facilitates the clinical categorization of ccRCC progression. Moreover, our findings underscore the significant potential of RCN1 as a ccRCC biomarker.

Calcineurin (CN) is a conserved Ca2+/calmodulin‐dependent phosphoprotein phosphatase that plays a key role in Ca2+ signaling. Regulator of calcineurin 1 (RCAN1), also known as Down syndrome critical region gene 1 (DSCR1), interacts with calcineurin and inhibits calcineurin‐dependent signaling in various organisms. Ppb1, the fission yeast calcineurin regulates Cl−‐homeostasis, and Ppb1 deletion induces MgCl2 hypersensitivity. Here, we characterize the conserved and novel roles of the fission yeast RCAN1 homolog rcn1+. Consistent with its role as an endogenous calcineurin inhibitor, Rcn1 overproduction reproduced the calcineurin‐null phenotypes, including MgCl2 hypersensitivity and inhibition of calcineurin signaling upon extracellular Ca2+ stimuli as evaluated by the nuclear translocation and transcriptional activation of the calcineurin substrate Prz1. Notably, overexpression of rcn1+ causes hypersensitivity to arsenite, whereas calcineurin deletion induces arsenite tolerance, showing a phenotypic discrepancy between Rcn1 overexpression and calcineurin deletion. Importantly, although Rcn1 deletion induces modest sensitivities to arsenite and MgCl2 in wild‐type cells, the arsenite tolerance, but not MgCl2 sensitivity, associated with Ppb1 deletion was markedly suppressed by Rcn1 deletion. Collectively, our findings reveal a previously unrecognized functional collaboration between Rcn1 and calcineurin, wherein Rcn1 not only negatively regulates calcineurin in the Cl− homeostasis, but also Rcn1 mediates calcineurin signaling to modulate arsenite cytotoxicity. [ABSTRACT FROM AUTHOR]

Abstract Background MicroRNAs (miRNAs) play a crucial role in gene expression and regulation, with dysregulation of miRNA function linked to various diseases, including hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC). There is still a gap in understanding the regulatory relationship between miRNAs and mRNAs in HCV-HCC. This study aimed to investigate the function and effects of persistent HCV-induced miRNA expression on gene regulation in HCC. Methods MiRNA array data were used to identify differentially expressed miRNAs and their targets, and miRNAs were analyzed via DIANA for KEGG pathways, gene ontology (GO) functional enrichment, and Ingenuity Pathways Analysis (IPA) for hepatotoxicity, canonical pathways, associated network functions, and interactive networks. Results Seventeen miRNAs in L-HCV and 9 miRNAs in S-HCV were differentially expressed, and 5 miRNAs in L-HCV and 5 miRNAs in S-HCV were significantly expressed in liver hepatocellular carcinoma (LIHC) tumors. Grouped miRNA survival analysis showed that L-HCV miRNAs were associated with survival in LIHC, and miRNA‒mRNA targets regulated viral carcinogenesis and cell cycle alteration through cancer pathways in LIHC. MiRNA-regulated RCN1 was suppressed through miRNA-oncogene interactions, and suppression of RCN1 inhibited invasion and migration in HCC. Conclusion Persistent HCV infection induced the expression of miRNAs that act as tumor suppressors by inhibiting oncogenes in HCC. RCN1 was suppressed while miRNAs were upregulated, demonstrating an inverse relationship. Therefore, hsa-miR-215-5p, hsa-miR-10b-5p, hsa-let-7a-5p and their target RCN1 may be ideal biomarkers for monitoring HCV-HCC progression. Graphical Abstract

Objective: To investigate the relation of clinicopathological characteristics and RCN1 and GRP78 expression levels in colorectal cancer, and explore their prognostic value. Methods: The expression of RCN1 and HSPA5 mRNA in colorectal cancer( CRC) was examined using the TCGA and UALCAN databases, and clinical samples were obtained for immunohistochemistry to confirm the expression of both. Then, the correlation with clinicopathological features and its prognostic value were analyzed. Results: According to a bioinformatics analysis, RCN1 and HSPA5 mRNA were both significantly overexpressed in CRC and had a positive correlation.The expression of RCN1 was correlated with N stage and TP53 mutations, the expression of HSPA5 was higher in mucinous adenocarcinomas. In CRC tissues, RCN1 and GRP78 protein were both strongly expressed and localized in the cytoplasm. GRP78 expression was significantly correlated with T stage. The Kaplan-Meier survival analysis curve indicates that patients with higher RCN1 expression had significantly shorter DFS than those with lower expression and a tendency toward shorter OS.According to COX regression analysis,DFS in CRC was found to be independently associated with tumor nerve invasion, TNM stage, and high RCN1 expression, Correlation analysis: RCN1 and GRP78 expression were positively associated in CRC. Conclusion: RCN1 is an independent risk factor for a poor prognosis in colorectal cancer (CRC) and has a positive correlation with GRP78 expression. [ABSTRACT FROM AUTHOR]

Background: MicroRNAs (miRNAs) play a crucial role in gene expression and regulation, with dysregulation of miRNA function linked to various diseases, including hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC). There is still a gap in understanding the regulatory relationship between miRNAs and mRNAs in HCV-HCC. This study aimed to investigate the function and effects of persistent HCV-induced miRNA expression on gene regulation in HCC. Methods: MiRNA array data were used to identify differentially expressed miRNAs and their targets, and miRNAs were analyzed via DIANA for KEGG pathways, gene ontology (GO) functional enrichment, and Ingenuity Pathways Analysis (IPA) for hepatotoxicity, canonical pathways, associated network functions, and interactive networks. Results: Seventeen miRNAs in L-HCV and 9 miRNAs in S-HCV were differentially expressed, and 5 miRNAs in L-HCV and 5 miRNAs in S-HCV were significantly expressed in liver hepatocellular carcinoma (LIHC) tumors. Grouped miRNA survival analysis showed that L-HCV miRNAs were associated with survival in LIHC, and miRNA‒mRNA targets regulated viral carcinogenesis and cell cycle alteration through cancer pathways in LIHC. MiRNA-regulated RCN1 was suppressed through miRNA-oncogene interactions, and suppression of RCN1 inhibited invasion and migration in HCC. Conclusion: Persistent HCV infection induced the expression of miRNAs that act as tumor suppressors by inhibiting oncogenes in HCC. RCN1 was suppressed while miRNAs were upregulated, demonstrating an inverse relationship. Therefore, hsa-miR-215-5p, hsa-miR-10b-5p, hsa-let-7a-5p and their target RCN1 may be ideal biomarkers for monitoring HCV-HCC progression. [ABSTRACT FROM AUTHOR]

Reticulocalbin‐1 (RCN1) is expressed aberrantly and at a high level in various tumors, including acute myeloid leukemia (AML), yet its impact on AML remains unclear. In this study, we demonstrate that RCN1 knockdown significantly suppresses the viability of bone marrow mononuclear cells (BMMNCs) from AML patients but does not affect the viability of granulocyte colony‐stimulating factor (G‐CSF)‐mobilized peripheral blood stem cells (PBSCs) from healthy donors in vitro. Downregulation of RCN1 also reduces the viability of AML cell lines. Further studies showed that the RCN1 knockdown upregulates type I interferon (IFN‐1) expression and promotes AML cell pyroptosis through caspase‐1 and gasdermin D (GSDMD) signaling. Deletion of the mouse Rcn1 gene inhibits the viability of mouse AML cell lines but not the hematopoiesis of mouse bone marrow. In addition, RCN1 downregulation in human AML cells significantly inhibited tumor growth in the NSG mouse xenograft model. Taken together, our results suggest that RCN1 may be a potential target for AML therapy.

Reticulocalbin‐1 (RCN1) is expressed aberrantly and at a high level in various tumors, including acute myeloid leukemia (AML), yet its impact on AML remains unclear. In this study, we demonstrate that RCN1 knockdown significantly suppresses the viability of bone marrow mononuclear cells (BMMNCs) from AML patients but does not affect the viability of granulocyte colony‐stimulating factor (G‐CSF)‐mobilized peripheral blood stem cells (PBSCs) from healthy donors in vitro. Downregulation of RCN1 also reduces the viability of AML cell lines. Further studies showed that the RCN1 knockdown upregulates type I interferon (IFN‐1) expression and promotes AML cell pyroptosis through caspase‐1 and gasdermin D (GSDMD) signaling. Deletion of the mouse Rcn1 gene inhibits the viability of mouse AML cell lines but not the hematopoiesis of mouse bone marrow. In addition, RCN1 downregulation in human AML cells significantly inhibited tumor growth in the NSG mouse xenograft model. Taken together, our results suggest that RCN1 may be a potential target for AML therapy. [ABSTRACT FROM AUTHOR]

Protein phosphatase 2A (PP2A) is a key regulator of plant growth and development, but its role in the endoplasmic reticulum (ER) stress response remains elusive. In this study, we investigated the function of PP2A under ER stress using loss-of-function mutants of ROOTS CURL of NAPHTHYLPHTHALAMIC ACID1 (RCN1), a regulatory A1 subunit isoform of Arabidopsis PP2A. RCN1 mutants (rcn1-1 and rcn1-2) exhibited reduced sensitivity to tunicamycin (TM), an inhibitor of N-linked glycosylation and inducer of unfolded protein response (UPR) gene expression, resulting in less severe effects compared to wild-type plants (Ws-2 and Col-0). TM negatively impacted PP2A activity in Col-0 plants but did not significantly affect rcn1-2 plants. Additionally, TM treatment did not influence the transcription levels of the PP2AA1 (RCN1), 2 , and 3 genes in Col-0 plants. Cantharidin, a PP2A inhibitor, exacerbated growth defects in rcn1 plants and alleviated TM-induced growth inhibition in Ws-2 and Col-0 plants. Furthermore, cantharidin treatment mitigated TM hypersensitivity in ire1a&b and bzip28&60 mutants. These findings suggest that PP2A activity is essential for an efficient UPR in Arabidopsis. • PP2A function in ER stress response in plants explored. • rcn1 mutants show reduced sensitivity to ER stress. • PP2A inhibitor cantharidin mitigates plant ER stress. • Findings enhance understanding of UPR signaling pathways. [ABSTRACT FROM AUTHOR]

Reticulocalbin1 (RCN1) is implicated in tumorigenesis and tumour progression. However, whether RCN1‐mediated bone metastasis of non‐small cell lung cancer (NSCLC) cells was elusive. Here, we assessed the effect of osteoblast‐conditioned medium (CM) on proliferation and migration of NSCLC cell line, NCI‐H1299 and NCI‐H460 cells, and identified the soluble mediators in CMs from osteoblasts and NSCLC cells using MTT, Clonogenicity, Transwell, wound healing, RT‐PCR, and Western blotting assays, and LC‐MS/MS analysis, respectively. Furthermore, the role of RCN1 was investigated in NSCLC cells cultured with or without osteoblast‐CM. Tumour growth and bone resorption were measured in a nude mouse model bearing NCI‐H1299 cells transduced with shRNA/RCN1 vector using in vivo imaging technique and micro‐CT. The results showed that RCN1 with a higher abundance in osteoblast‐CM, which was present in extracellular vesicles (EVs), enhanced RCN1 expression in NSCLC cells. Osteoblast‐CM partially offset the inhibitory effect of RCN1 depletion on proliferation and migration of NSCLC cells. RCN1 depletion‐induced endoplasmic reticulum (ER) stress caused by increasing GRP78, CHOP, IRE1α, p‐IRE1α, p‐PERK and p‐JNK, which was positively regulated by self‐induced autophagy, contributed to suppression of proliferation and migration in NCI‐H1299 cells. Therefore, osteoblasts produced RCN1 to transfer into NSCLC cells partially through EVs, facilitating proliferation and migration of NSCLC cells via blocking ER stress. RCN1 could be required for proliferation and migration of NSCLC cells regulated by osteoblast‐CM. [ABSTRACT FROM AUTHOR]

Abstract Background The initiation of flowering transition in rice (Oryza sativa) is a complex process regulated by genes and environment. In particular, drought can interfere with flowering; therefore, many plants hasten this process to shorten their life cycle under water scarcity, and this is known as drought-escape response. However, rice has other strategies; for example, drought stress can delay flowering instead of accelerating it. RICE CENTRORADIALIS 1 (RCN1) is a TERMINAL FLOWER-like gene that influences rice flowering transition and spike differentiation. It interacts with 14–3-3 proteins and transcription factor OsFD1 to form a florigen repression complex that suppresses flowering transition in rice. Results In this study, we explored the role of RCN1 in the molecular pathway of drought-regulated flowering transition. The rcn1 mutant plants displayed early heading under both normal water and drought stress conditions, and they were more insensitive to drought stress than the wild-type plants. Abscisic acid (ABA) signaling-mediated drought-induced RCN1 is involved in this process. Conclusions Thus, RCN1 plays an important role in the process of drought stress inhibiting flowering transition. It may worked by suppressing the protein function rather than transcription of HEADING DATE 3a.

Glioblastoma multiform is a lethal primary brain tumor derived from astrocytic, with a poor prognosis in adults. Reticulocalbin-1 (RCN1) is a calcium-binding protein, dysregulation of which contributes to tumorigenesis and progression in various cancers. The present study aimed to identify the impact of RCN1 on the outcomes of patients with Glioblastoma multiforme (GBM). The study applied two public databases to require RNA sequencing data of Glioblastoma multiform samples with clinical data for the construction of a training set and a validation set, respectively. We used bioinformatic analyses to determine that RCN1 could be an independent factor for the overall survival of Glioblastoma multiform patients. In the training set, the study constructed a predictive prognostic model based on the combination of RCN1 with various clinical parameters for overall survival at 0.5-, 1.0-, and 1.5-years, as well as developed a nomogram, which was further validated by validation set. Pathways analyses indicated that RCN1 was involved in KEAS and MYC pathways and apoptosis. In vitro experiments indicated that RCN1 promoted cell invasion of Glioblastoma multiform cells. These results illustrated the prognostic role of RCN1 for overall survival in Glioblastoma multiform patients, indicated the promotion of RCN1 in cell invasion, and suggested the probability of RCN1 as a potential targeted molecule for treatment in Glioblastoma multiform.

Moringa oleifera Lam is a medicinal plant that had been shown to have anticancer activity. Previously, the hexane fraction of the seeds (HF-CEE) was found to inhibit breast cancer (MCF7) cell proliferation at IC 50 of 130 μg/ml. However, the mechanism by which HF-CEE inhibits MCF7 cells remained unknown. To elucidate the mechanism, we investigated the effect of HF-CEE on apoptosis, cell cycle, and the cell proteome of MCF7 cells. The HF-CEE was prepared by fractionating the non-polar fraction of the ethanolic extract of M. oleifera seeds using the hexane solvent. The antiproliferative effect of HF-CEE on the growth of MDA-MB-231 cells (another breast cancer cells) was performed using Presto Blue assay. The morphologies of the untreated and treated cells (MCF7, MDA-MB-231 and MCF 10A cells) were observed using inverted light microscope. The apoptotic and cell cycle arrest effects of HF-CEE on MCF7 cells were determined using flow cytometry analyses. 2-DE proteomics analysis was employed to identify the protein biomarkers of MCF7 cells that have their expression levels altered by HF-CEE treatment. qRT-PCR method was used to validate the 2-DE results. The gene ontology analysis was carried out using PANTHER server to identify the mechanisms and biological processes that are dependent on the functions of the identified biomarkers. Our results showed that HF-CEE selectively inhibited the proliferation of the breast cancer cells (MCF7 and MDA-MB-231) but not the MCF 10A non-tumor cells. MCF7 and MDA-MB-231 cells treated with HF-CEE showed morphological properties of dead cells, but MCF 10A cells did not. HF-CEE also induced apoptosis and cell cycle arrest at the S and G2/M phases in MCF7 cells. 2-DE analysis revealed that HF-CEE altered the regulation of several cancer-related proteins in MCF7 cells, such as heat shock protein 60 (HSP60), nucleophosmin (NPM), protein disulphide isomerase (PDIA1), phosphoglycerate kinase 1 (PGK1), and reticulocalbin 1 (RCN1). In conclusion, HF-CEE induced cell death in MCF7 cells via apoptosis, cell cycle arrest, and other mechanisms such as the alteration of the expression of proteins that are involved in glycolysis, cancer invasiveness and metastasis among others. Results of this study provide further insights into the mechanisms that underlie the antiproliferative effect of HF-CEE on MCF7 cells. • Moringa oleifera seed hexane fraction (HF-CEE) selectively inhibits breast cancer cells. • HF-CEE induces apoptosis in MCF7 cells. • HF-CEE arrests cell cycle progression at S and G2/M phases. • HF-CEE regulates cancer biomarkers such as HSP60, NPM, PGK1, RCN1, and PDIA1. [ABSTRACT FROM AUTHOR]

Aim Activation of the kinase RAF and its downstream targets leads to cardiomyocyte hypertrophy. It has been hypothesized that B-RAF might be the main activator of MEK in various cell types. Therefore, the aim of this study was to investigate the role of B-RAF and its modulating factors in cardiomyocyte hypertrophy. Methods and results Neonatal rat cardiomyocytes were pre-treated with and without the specific B-RAF inhibitor SB590885 and then stimulated with phenylephrine to induce hypertrophy. Inhibition of B-RAF completely impeded the hypertrophic response and led to a significant reduction of MEK1/2 phosphorylation. By applying a eukaryotic cDNA expression screen, based on a dual-luciferase reporter assay for B-RAF activity measurement, we identified RCN1 as a new negative modulator of B-RAF activity. Adenovirus-mediated overexpression of reticulocalbin 1 (RCN1) completely impeded phenylephrine-induced hypertrophy and led to significantly reduced MEK1/2 phosphorylation. Conversely, adenoviral knockdown of RCN1 with a specific synthetic miRNA induced cardiomyocyte hypertrophy and significantly increased MEK1/2 phosphorylation. Conclusions In summary, our results show that the inhibition of B-RAF abolishes cardiomyocyte hypertrophy and we identified RCN1 as novel negative modulator of cardiomyocyte hypertrophy by inhibition of the mitogen-activated protein kinase signalling cascade. Our results show that B-RAF kinase activity is essential for cardiac hypertrophy and RCN1, its newly identified negative regulator, abolishes hypertrophic response of cardiomyocytes in vitro. [ABSTRACT FROM PUBLISHER]

Abstract: Fungi and animals constitute sister kingdoms in the eukaryotic domain of life. The major classes of transporters, channels, sensors, and effectors that move and respond to calcium ions were already highly networked in the common ancestor of fungi and animals. Since that time, some key components of the network have been moved, altered, relocalized, lost, or duplicated in the fungal and animal lineages and at the same time some of the regulatory circuitry has been dramatically rewired. Today the calcium transport and signaling networks in fungi provide a fresh perspective on the scene that has emerged from studies of the network in animal cells. This review provides an overview of calcium signaling networks in fungi, particularly the model yeast Saccharomyces cerevisiae, with special attention to the dominant roles of acidic calcium stores in fungal cell physiology. [Copyright &y& Elsevier]

Abstract: The protein phosphatase calcineurin is a key mediator of virulence and antifungal susceptibility of multiple fungal pathogens including Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus, and has clinical potential as a therapeutic target to increase the efficacy of the current antifungal armamentarium. Despite the importance of this signaling pathway, few components of the calcineurin-signaling pathway are known in C. albicans. Here we identified and analyzed additional components of the C. albicans calcineurin cascade, including the RCN1 (regulator of calcineurin1), MID1, and CCH1 genes, which mediate calcineurin functions in other species. When heterologously expressed in Saccharomyces cerevisiae, C. albicans Rcn1 inhibited calcineurin function. Although rcn1/rcn1, mid1/mid1, and cch1/cch1 mutant strains share some phenotypes with calcineurin mutants, they do not completely recapitulate the phenotypes of a calcineurin mutant strain. These studies extend our understanding of the C. albicans calcineurin signaling cascade and its host-niche specific role in virulence. [Copyright &y& Elsevier]

Abstract: Pan-vertebrate developmental cis-regulatory elements are discernible as highly conserved noncoding elements (HCNEs) and are often dispersed over large areas around the pleiotropic genes whose expression they control. On the loci of two developmental transcription factor genes, SOX3 and PAX 6, we demonstrate that HCNEs conserved between human and zebrafish can be systematically and reliably tested for their regulatory function in multiple stable transgenes in zebrafish, and their genomic reach estimated with confidence using synteny conservation and HCNE density along these loci. HCNEs of both human and zebrafish function as specific developmental enhancers in zebrafish. We show that human HCNEs result in expression patterns in zebrafish equivalent to those in mouse, establishing zebrafish as a suitable model for large-scale testing of human developmental enhancers. Orthologous human and zebrafish enhancers underwent functional evolution within their sequence and often directed related but non-identical expression patterns. Despite an evolutionary distance of 450 million years, one pax6 HCNE drove expression in identical areas when comparing zebrafish vs. human HCNEs. HCNEs from the same area often drive overlapping patterns, suggesting that multiple regulatory inputs are required to achieve robust and precise complex expression patterns exhibited by developmental genes. [Copyright &y& Elsevier]

Glioblastoma multiform is a lethal primary brain tumor derived from astrocytic, with a poor prognosis in adults. Reticulocalbin-1 (RCN1) is a calcium-binding protein, dysregulation of which contributes to tumorigenesis and progression in various cancers. The present study aimed to identify the impact of RCN1 on the outcomes of patients with Glioblastoma multiforme (GBM). The study applied two public databases to require RNA sequencing data of Glioblastoma multiform samples with clinical data for the construction of a training set and a validation set, respectively. We used bioinformatic analyses to determine that RCN1 could be an independent factor for the overall survival of Glioblastoma multiform patients. In the training set, the study constructed a predictive prognostic model based on the combination of RCN1 with various clinical parameters for overall survival at 0.5-, 1.0-, and 1.5-years, as well as developed a nomogram, which was further validated by validation set. Pathways analyses indicated that RCN1 was involved in KEAS and MYC pathways and apoptosis. In vitro experiments indicated that RCN1 promoted cell invasion of Glioblastoma multiform cells. These results illustrated the prognostic role of RCN1 for overall survival in Glioblastoma multiform patients, indicated the promotion of RCN1 in cell invasion, and suggested the probability of RCN1 as a potential targeted molecule for treatment in Glioblastoma multiform., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Lu, Chen, Liang, Ou, Zhang, Yue and Xie.)

Simple Summary: A key molecule, EGFRvIII has been shown to provide several growth advantages for brain tumors. However, we have found a new mechanism in which the EGFRvIII provides increased survival to brain cancer cells when under sub-optimal conditions. Specifically, we have found that the EGFRvIII drives the expression of a molecule called Reticulocalbin 1 (RCN1) and that RCN1 blocks cell stress and cell death, thereby allowing cells to survive and proliferate. Importantly, these findings will allow for the generation of drugs that block the function of EGFRvIII and RCN1 with the hope that these drugs will induce brain cancer cell death. Reticulocalbin 1 (RCN1) is an endoplasmic reticulum (ER)-residing protein, involved in promoting cell survival during pathophysiological conditions that lead to ER stress. However, the key upstream receptor tyrosine kinase that regulates RCN1 expression and its potential role in cell survival in the glioblastoma setting have not been determined. Here, we demonstrate that RCN1 expression significantly correlates with poor glioblastoma patient survival. We also demonstrate that glioblastoma cells with expression of EGFRvIII receptor also have high RCN1 expression. Over-expression of wildtype EGFR also correlated with high RCN1 expression, suggesting that EGFR and EGFRvIII regulate RCN1 expression. Importantly, cells that expressed EGFRvIII and subsequently showed high RCN1 expression displayed greater cell viability under ER stress compared to EGFRvIII negative glioblastoma cells. Consistently, we also demonstrated that RCN1 knockdown reduced cell viability and exogenous introduction of RCN1 enhanced cell viability following induction of ER stress. Mechanistically, we demonstrate that the EGFRvIII-RCN1-driven increase in cell survival is due to the inactivation of the ER stress markers ATF4 and ATF6, maintained expression of the anti-apoptotic protein Bcl-2 and reduced activity of caspase 3/7. Our current findings identify that EGFRvIII regulates RCN1 expression and that this novel association promotes cell survival in glioblastoma cells during ER stress. [ABSTRACT FROM AUTHOR]

We investigated the expression of reticulocalbin-1 (RCN1) and its prognostic significance in non-small cell lung cancer (NSCLC). RCN1 expression was evaluated by immunohistochemical analysis with tissue microarrays in NSCLC tissues and matched adjacent noncancerous tissues. Furthermore, quantitative polymerase chain reaction and Western blot were also used to examine the expression of RCN1. Moreover, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, clone formation, and transwell assays were used to measure cell proliferation, migration, and invasion. Lastly, we used the Kaplan-Meier method and log-rank test to compare overall survival rates between the RCN1-high expression group and the RCN1-low expression group. In this study, immunohistochemistry by tissue microarray at RCN1 expression was significantly up-regulated in NSCLC tissues compared with adjacent noncancerous tissues. We further confirmed the up-regulation of RCN1 by quantitative polymerase chain reaction and Western blot assay. RCN1 expression level was closely related to lymph node metastasis (P < .001) and TNM stage (P = .012). Kaplan-Meier analysis showed that high RCN1 expression was remarkably associated with poor prognosis with NSCLC patients. A suppression of cell proliferation, migration, and invasion was obtained in A549 cells treated with RCN1 small interfering RNA. Our data indicate that RCN1 expression may have an vital role at promoting the occurrence of NSCLC, and it may be a vital molecular marker in the diagnosis and prognosis of NSCLC patients., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Summary Ethylene signaling in Arabidopsis begins with a family of five ethylene receptors that regulate the activity of the Raf-like kinase, CTR1. Recent work to identify novel factors required for modulating ethylene signaling resulted in the isolation of enhanced ethylene response 1 (eer1 ), a mutant that displays both increased sensitivity and increased amplitude of response to ethylene. Molecular cloning of eer1 reveals that its mutant phenotype results from a loss-of-function mutation in the previously characterized RCN1 , one of three PP2A A regulatory subunits in Arabidopsis . Our analysis shows that neither RCN1 expression nor PP2A activity is regulated by ethylene. Instead, we found that Arabidopsis PP2A-1C, a PP2A catalytic subunit previously characterized as interacting with RCN1, associates strongly with the kinase domain of CTR1 in vitro . This likely represents a role for PP2A in modulation of CTR1 activity because an in vitro kinase assay did not reveal phosphorylation of either RCN1 or PP2A-1C by CTR1, indicating that neither of them is a substrate for CTR1. PP2A activity is required for Ras-dependent activation of mammalian Raf, with reductions in PP2A activity significantly compromising the effectiveness of this mechanism. Our genetic and biochemical results suggest that a similar requirement for PP2A activity exists for ethylene signaling, with loss-of-function mutations affecting PP2A activity possibly reducing the effectiveness of CTR1 activation, thus lowering the threshold required for manifestation of ethylene response. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma (RCC) biomarkers are necessary for diagnosis and prognosis. They serve to monitor therapy response and follow-up, as drug targets, and therapy predictors in personalized treatments. Proteomics is a suitable method for biomarker discovery. Here we investigate differential protein expression in RCC, and we evaluate Reticulocalbin 1 (RCN1) use as a new potential marker. Neoplastic and healthy tissue samples were collected from 24 RCC patients during radical nephrectomy. Seven specimens were firstly processed by proteomic analysis (2-DE and MALDI-TOF) and 18 differentially expressed proteins from neoplastic and healthy renal tissues were identified. Among them, RCN1 was over-expressed in all cancer specimens analyzed by proteomics. Consequently RCN1 use as a potential marker was further evaluated in all 24 donors. RCN1 expression was verified by Western blotting (WB) and immunohistochemistry (IHC). WB analysis confirmed RCN1 over-expression in 21 out of 24 tumor specimens, whereas IHC displayed focal or diffuse expression of RCN1 in all 24 RCC tissues. Thus RCN1 appears as a potential marker for clinical approaches. A larger histopathological trial will clarify the prognostic value of RCN1 in RCC., Biological Significance: The present work aimed at finding new biomarkers for RCC - a life-threatening disease characterized by high incidence in Western countries - by performing differential proteomic analysis of neoplastic and normal renal tissues obtained from a small cohort of RCC patients. Some of the identified proteins have been previously associated to renal cancer however data confirming the possible use of these proteins in clinical practice are not available to date. By IHC we demonstrated that RCN1 could be easily employed in clinical practice, confirming RCN1 over-expression in RCC tissues of all examined patients, and weak protein expression in healthy renal tissues only in correspondence to the renal tubule section. These data indicate a promising role of RCN1 as a possible marker in RCC and indicate the proximal convoluted renal tubule as a putative origin point for RCC. Since IHC staining displayed different grades of intensity in tested tissues, we hypothesized that RCN1 could also be employed as a prognostic marker or as a response predictor for RCC-targeted therapy. To test such a hypothesis, a larger retrospective trial on paraffin-embedded tissues obtained from radical or partial nephrectomy of RCC patients is planned to be performed by our group., (© 2013.)

Candida glabrata is an emerging human fungal pathogen that is frequently drug tolerant, resulting in difficulties in treatment and a higher mortality in immunocompromised patients. The calcium-activated protein phosphatase calcineurin plays critical roles in controlling drug tolerance, hyphal growth, and virulence in diverse fungal pathogens via distinct mechanisms involving survival in serum or growth at host temperature (37° and higher). Here, we comprehensively studied the calcineurin signaling cascade in C. glabrata and found novel and uncharacterized functions of calcineurin and its downstream target Crz1 in governing thermotolerance, intracellular architecture, and pathogenesis in murine ocular, urinary tract, and systemic infections. This represents a second independent origin of a role for calcineurin in thermotolerant growth of a major human fungal pathogen, distinct from that which arose independently in Cryptococcus neoformans. Calcineurin also promotes survival of C. glabrata in serum via mechanisms distinct from C. albicans and thereby enables establishment of tissue colonization in a murine systemic infection model. To understand calcineurin signaling in detail, we performed global transcript profiling analysis and identified calcineurin- and Crz1-dependent genes in C. glabrata involved in cell wall biosynthesis, heat shock responses, and calcineurin function. Regulators of calcineurin (RCN) are a novel family of calcineurin modifiers, and two members of this family were identified in C. glabrata: Rcn1 and Rcn2. Our studies demonstrate that Rcn2 expression is controlled by calcineurin and Crz1 to function as a feedback inhibitor of calcineurin in a circuit required for calcium tolerance in C. glabrata. In contrast, the calcineurin regulator Rcn1 activates calcineurin signaling. Interestingly, neither Rcn1 nor Rcn2 is required for virulence in a murine systemic infection model. Taken together, our findings show that calcineurin signaling plays critical roles in thermotolerance and virulence, and that Rcn1 and Rcn2 have opposing functions in controlling calcineurin signaling in C. glabrata.