Corrigendum: The epithelial to mesenchymal transition related gene calumenin is an adverse prognostic factor of bladder cancer correlated with tumor microenvironment remodeling, gene mutation, and ferroptosis

[This corrects the article DOI: 10.3389/fonc.2021.683951.].

Calumenin, a Ca2+ Binding Protein, Is Required for Dauer Formation in Caenorhabditis elegans

Caenorhabditis elegans can adapt and survive in dynamically changing environments by the smart and delicate switching of molecular plasticity. C. elegans dauer diapause is a form of phenotypic and developmental plasticity that induces reversible developmental arrest upon environmental cues. An ER (endoplasmic reticulum)-resident Ca²⁺ binding protein, calumenin has been reported to function in a variety of malignant diseases in vertebrates and in the process of muscle contraction-relaxation. In C. elegans, CALU-1 is known to function in Ca²⁺-regulated behaviors (pharyngeal pumping and defecation) and cuticle formation. The cuticles of dauer larvae are morphologically distinct from those of larvae that develop in favorable conditions. The structure of the dauer cuticle is thicker and more highly reinforced than that of other larval stages to protect dauer larvae from various environmental insults. Since the calu-1(tm1783) mutant exhibited abnormal cuticle structures such as highly deformed annuli and alae, we investigated whether CALU-1 is involved in dauer formation or not. Ascaroside pheromone (ascr#2) and crude daumone were used under starvation conditions to analyze the rate of dauer formation in the calu-1(tm1783) mutant. Surprisingly, the dauer ratio of the calu-1(tm1783) mutant was extremely low compared to that of the wild type. In fact, the calu-1(tm1783) mutants were mostly unable to enter diapause. We also found that calu-1 is expressed in body-wall muscle and AIA interneurons at the dauer stage. Taken together, our results suggest that CALU-1 is required for normal entry into diapause in C. elegans.

The Epithelial to Mesenchymal Transition Related Gene Calumenin Is an Adverse Prognostic Factor of Bladder Cancer Correlated With Tumor Microenvironment Remodeling, Gene Mutation, and Ferroptosis

The tumor microenvironment (TME) plays a critical regulatory role in bladder cancer (BLCA) progression and metastasis. Epithelial-mesenchymal transition (EMT) presents as an essential mechanism of tumor invasion and metastasis. Accumulating pieces of evidence indicated that several microenvironmental factors, including fibroblasts, endothelial, and immune cells, induced EMT in tumor cells. As a hallmark gene of the EMT process, calumenin (CALU) was previously reported to directly impact cancer metastasis. However, the functions and molecular mechanisms of CALU have been rarely reported in BLCA. By multi-omics bioinformatics analysis of 408 TCGA BLCA patients, we demonstrated that CALU was an independent risk factor for BLCA outcome. Subsequently, we verified the correlation of CALU with cancer-associated fibroblasts (CAFs) and tumor-infiltrating immune cells. The results suggested a positive correlation of CALU with CAFs, CD8+ T cells and macrophages. Also, CALU was significantly associated with multiple immune checkpoint-related genes, which ultimately influenced patients' responsiveness to immunotherapy. Further, we found that the impact of CALU on BLCA prognosis might also be correlated with gene mutations and ferroptosis. Finally, we validated the roles of CALU by single-cell RNA sequencing, PCR and immunohistochemistry. In conclusion, we found that CALU affected BLCA prognosis associated with multiple mechanisms, including TME remodeling, gene mutation and ferroptosis. Further studies on CALU may provide new targets for BLCA immunotherapy and precision medicine.

S100A6, Calumenin and Cytohesin 2 as Biomarkers for Cutaneous Involvement in Systemic Sclerosis Patients: A Case Control Study

BACKGROUND

Systemic sclerosis (Ssc) is an autoimmune disease with incomplete known physiopathology. There is a high number of candidate proteomic biomarkers for Ssc that have not yet been confirmed on independent Ssc cohorts. The aim of the study was to confirm circulating S100A6, calumenin, and cytohesin 2 as biomarkers for Ssc.

METHODS

53 Ssc patients and 26 age- and gender-matched controls were included. Serum S100A6, calumenin, and cytohesin 2 were evaluated with commercial ELISA kits. Associations between serum expression and clinical Ssc characteristics were evaluated.

RESULTS

Serum calumenin, S100A6, and cytohesin 2 were higher in Ssc patients compared to controls. Calumenin associated with extensive cutaneous fibrosis, frequency of Raynaud phenomenon, and low complement level, and had a tendency to be higher in Ssc patients with pulmonary fibrosis. S100A6 correlated with the number of active digital ulcers. Serum cytohesin 2 levels were higher in patients with teleangiectasia and associated with pulmonary artery pressure.

CONCLUSIONS

Serum calumenin, S100A6, and cytohesin 2 were confirmed as biomarkers on an independent group of Ssc patients. Calumenin had the best predictive capacity for cutaneous Ssc manifestations. Future studies are needed to evaluate the prognostic value of these biomarkers and evaluate them as possible therapeutic targets.

Calumenin contributes to epithelial-mesenchymal transition and predicts poor survival in glioma

Background

Calumenin (CALU) has been reported to be associated with invasiveness and metastasis in some malignancies. However, in glioma, the role of CALU remains unclear.

Methods

Clinical and transcriptome data of 998 glioma patients, including 301 from CGGA and 697 from TCGA dataset, were included. R language was used to perform statistical analyses.

Results

CALU expression was significantly upregulated in more malignant gliomas, including higher grade, IDH wildtype, mesenchymal, and classical subtype. Gene Ontology analysis revealed that CALU-correlated genes were mainly enriched in cell/biological adhesion, response to wounding, and extracellular matrix/structure organization, all of which were strongly correlated with the epithelial-mesenchymal transition (EMT) phenotype. GSEA further validated the profound involvement of CALU in EMT. Subsequent GSVA suggested that CALU was particularly correlated with three EMT signaling pathways, including TGFβ, PI3K/AKT, and hypoxia pathway. Furthermore, CALU played synergistically with EMT key markers, including N-cadherin, vimentin, snail, slug, and TWIST1. Survival and Cox regression analysis showed that higher CALU predicted worse survival, and the prognostic value was independent of WHO grade and age.

Conclusions

CALU was correlated with more malignant phenotypes in glioma. Moreover, CALU seemed to serve as a pro-EMT molecular target and could contribute to predict prognosis independently in glioma.

[Astragalus injection mediates autophagy and myocardial remodeling in rats with ischemic cardiomyopathy through calumenin]

OBJECTIVE

To study the effects of astragalus injection on myocardial remodeling, calumenin and autophagy in rats with ischemic cardiomyopathy.

METHODS

Thirty-six male SD rats were divided into normal control group, ischemic cardiomyopathy group and astragalus injection group, 12 in each group. Electrocardiogram (ECG) and echocardiography were performed before operation in three groups. Rats in ischemic cardiomyopathy group and astragalus injection group underwent thoracotomy and ligation of coronary artery for 20 minutes, then thoracic cavity was closed after reperfusion. In the astragalus injection group,10 g/kg body weight of Astragalus injection was injected once a week, four times in total. Four weeks after operation, rats in three groups were executed by echocardiography and their hearts were collected for Hematoxylin-Eosin (HE) staining and Van Gieson (VG) staining to observe myocardial pathological changes. Calumenin, LC3-I, LC3-II expressions and LC3-I/LC3-II ratio were detected by Western blot.

RESULTS

Compared with ischemic cardiomyopathy group, the echocardiography and myocardial pathology of rats in astragalus injection group changed obviously, and the expressions of calumenin, LC3-I, LC3-II and LC3-I/LC3-II ratio changed significantly (P＜0.01).

CONCLUSION

Astragalus injection has apparent inhibitory effect on ventricular remodeling and autophagy of myocardial cells in rats with ischemic cardiomyopathy, which may be mediated by calumenin.

Novel Findings of Anti-Filarial Drug Target and Structure-Based Virtual Screening for Drug Discovery

Lymphatic filariasis and onchocerciasis caused by filarial nematodes are important diseases leading to considerable morbidity throughout tropical countries. Diethylcarbamazine (DEC), albendazole (ALB), and ivermectin (IVM) used in massive drug administration are not highly effective in killing the long-lived adult worms, and there is demand for the development of novel macrofilaricidal drugs affecting new molecular targets. A Ca2+ binding protein, calumenin, was identified as a novel and nematode-specific drug target for filariasis, due to its involvement in fertility and cuticle development in nematodes. As sterilizing and killing effects of the adult worms are considered to be ideal profiles of new drugs, calumenin could be an eligible drug target. Indeed, the Caenorhabditis elegans mutant model of calumenin exhibited enhanced drug acceptability to both microfilaricidal drugs (ALB and IVM) even at the adult stage, proving the roles of the nematode cuticle in efficient drug entry. Molecular modeling revealed that structural features of calumenin were only conserved among nematodes (C. elegans, Brugia malayi, and Onchocerca volvulus). Structural conservation and the specificity of nematode calumenins enabled the development of drugs with good target selectivity between parasites and human hosts. Structure-based virtual screening resulted in the discovery of itraconazole (ITC), an inhibitor of sterol biosynthesis, as a nematode calumenin-targeting ligand. The inhibitory potential of ITC was tested using a nematode mutant model of calumenin.

[Effect of creatine phosphate sodium on miRNA378, miRNA378* and calumenin mRNA in adriamycin-injured cardiomyocytes]

OBJECTIVE

To investigate the effect of creatine phosphate sodium (sodium phosphocreatine) on miRNA378, miRNA378^* and calumenin mRNA in adriamycin-injured suckling mouse myocardium.

METHODS

The suckling mouse myocardium of primary culture were randomly divided into control group, adriamycin group and treatment group. To identify the suckling mouse myocardium, Smooth muscle actin-α (α-SMA) was monitored by immunohistochemical method. Cardiac function was evaluated by transthoracic echocardiography. The mRNA change of miRNA378, miRNA378^* and calumenin mRNA were detected by quantitative real-time PCR. The expression of calumenin and GRP78 were identified by western blot.

RESULTS

Mitochondrial damage and vacuolization were found in adriamycin-induced suckling mouse myocardium compared with control group, while creatine phosphate sodium could reduce this phenomenon. Compared with the control group, the mRNA of miRNA378, miRNA378^* and calumenin in adriamycin group was reduced, while creatine phosphate sodium could increase this phenomenon. The expression of calumenin and GRP78 were decreased after adriamycin treatment in suckling mouse myocardiums, creatine phosphate sodium increased the expression of calumenin and GRP78.

CONCLUSIONS

The results of this experiment might be closely related to the effects of that creatine phosphate sodium reduced the pathological mechanism of suckling mouse myocardium with myocarditis caused by adriamycin.

Protective effect of miR378* on doxorubicin-induced cardiomyocyte injury via calumenin

Doxorubicin (Dox) is a highly effective antitumor antibiotic, however myocardial toxicity severely limits its use clinically. The pathogenesis of doxorubicin-induced cardiomyopathy is unclear. In Dox cardiomyopathy mice, there is a decline in cardiac function, a change in myocardial pathology and a reduction in miR378* expression. Expression changes in calumenin, an endoplasmic reticulum stress (ERS) chaperone protein and pathway factor, as well as apoptosis, were observed in cardiomyocytes after doxorubicin-induced injury. However, miR378* increased calumenin expression, eased ERS, and reduced cardiomyocyte apoptosis, while, silencing miR378* reduced calumenin expression, aggravated ERS, and increased cardiomyocyte apoptosis. The above results indicate that miR378* alleviates ERS and inhibits the activation of the ERS-mediated apoptosis signaling pathway in cardiomyocytes via regulating calumenin expression, thereby reducing cardiomyocyte apoptosis after doxorubicin-induced injury. Increasing miR378* expression may be a new way to improve cardiac function and quality of life in patients with Dox cardiomyopathy.

Calumenin DNA methylation and gene expression in viral myocarditis

The main death reason is inflammatory response of myocardial tissue caused a sharp decline in myocardial contractility and heart failure. At present, viral myocarditis with heart failure is lack of effective and specific treatment. Basic and clinical studies have shown that intervention apoptosis is an effective way to prevent and cure heart failure. The mechanism of apoptosis is complex, endoplasmic reticulum (ER) stress is a new apoptotic signal transduction pathway was been found. In this study, the apoptosis could be increased in mice with CVB3 treatment. The ER stress related proteins GRP78, ATF4, CHOP were up-regulated in VMC. The mechanism of VMC regulated ERS induced apoptosis was identified. Calumenin protein could relieve ERS induced apoptosis in viral myocarditis in vivo. The DNA methylation of calumenin was analyzed in CON and VMC, however, we found VMC down-regulate the expression of calumenin unrelated with DNA methylation of calumenin.

[The correlation research on miRNA378* and calumenin,endoplasmic reticulum stress,apoptosis in suckling mouse myocardial cells infected with coxsackie virus B3]

OBJECTIVE

To investigate the effects of silencing miRNA378^* on apoptosis, endoplasmic reticulum stress and calumenin of cardiomyocyte with coxsackie virus B3 (CVB3) infection.

METHODS

Primary cultured suckling mouse myocardium were divided into control group (normal cell), coxsackie virus infection group (normal cell and coxsackie virus B3), miRNA378^* control group (normal cell +coxsackie virus B3+miRNA378^* empty plasmid), miRNA378^* silencing plasmid group(normal cells + coxsackie virus B3 + miRNA378^* silencing plasmid). Four groups of cells were transfected, infected and treated in CO₂ incubator at 37℃. The α-SMA protein, cell apoptosis rate, calumenin, glucose regulated protein 78 (GRP78), activation transcription factor 6(ATF6) and transcription factors c/ebp homologue protein (CHOP) in endoplasmic reticulum were analyzed.

RESULTS

By detecting α-SMA protein, the isolated suckling mouse ventricular myocardium were confirmed. TUNEL detection of different groups of ventricular cell apoptosis found that coxsackie virus group of ventricular myocytes apoptosis was significant. Compared with the coxsackie virus infection group of myocardial cells, miRNA378^* silencing plasmid expression of cardiomyocyte apoptosis cells significantly reduced(P<0.01). The expressions of GRP78, ATF6 and CHOP were increased compared with those infected by Coxsackie virus infection (P<0.01), while the expressions of calumenin were decreased (P<0.01).

CONCLUSIONS

CVB3 infected myocardial cells effected miRNA378^* expression. It can trigger endoplasmic reticulum stress and activates signaling pathway factor and increase myocardial cell apoptosis.>.

[Effects of caspase inhibitor z-VAD-fmk on the expressions of calumenin, caspase-3, GRP78 and GRP94 in adriamycin-injured cardiomyocytes]

OBJECTIVE

To study the effects of Caspase broad spectrum inhibitor Z-VAD-FMK on the expressions of calumenin,caspase-3, GRP78 and GRP94 in adriamycin-injured cardiomyocytes and to discuss whether there is a regulation relationship between calumenin and endo-plasmic reticulum stress and myocardial apoptosis.

METHODS

The primary cultured suckling mouse myocardium were randomly divided into control group (cardiomyocyte), adriamycin group (3 mg/L adriamycin + cardiomyocyte) and z-VAD-fm group (3 mg/L adriamycin + 0.1 μmol/L Z-VAD-fmk + cardiomyocyte), each group of cardiomyocytes were cultured in CO₂ incubator at 37℃ for 24 h (n=3). The expres-sion ofα -SMA protein in ventricular myocytes was detected by immunohistochemical method. The expressions of calumenin, GRP78, GRP94 and Caspase-3 in the myocardial cells were detected by Western blot.

RESULTS

Compared with the control group, the expression of calumenin in adriamycin induced myocardial cells was significantly decreased (P < 0.01), while the expressions of GRP78, GRP94 and Caspase-3 ex-pression were increased (P < 0.01). Compared with adriamycin group, the expression of calumenin in z-VAD-fm group was increased (P < 0.01), while the expressions of GRP78, GRP94 and caspase-3 were decreased (P < 0.01).

CONCLUSIONS

The caspase inhibitor z-VAD-fmk inhibited the expression of caspase and increased the expression of calumenin in adriamycin induced myocardial cells, and thus alleviated the endoplasmic reticulum stress.

[The relationship between miRNA378, calumenin and endoplasmic reticulum stress in suckling mouse myocardium with myocarditis caused by adriamycin]

OBJECTIVE

To investigate the relationship between miRNA378, calumenin and endoplasmic reticulum stress in suckling mouse myocardium with myocarditis caused by adriamycin.

METHODS

The suckling mouse myocardium of primary culture were randomly divided into control group, adriamycin group, lentivirus infection miRNA378 over expression control group, lentivirus infection miRNA378 over expression group, lentivirus infection miRNA378 silence control group and lentivirus infection miRNA378 silence group. Firstly to identify the suckling mouse myocardium, α-SMA was monitored by immunohistochemical method, and secondly the ventricular myocytes were transfered by lentivirus plasmids. Then the expression change of miRNA378, calumenin and glucose regulated protein 78(GRP78) mRNA were detected by Quantitative Real-time PCR.

RESULTS

Compared with the adriamycin infection group, the expression of calumenin mRNA in lentivirus infection miRNA378 over expression group was increased(P<0.01), while the expression of GRP78 mRNA was reduced(P<0.01); Compared with the adriamycin infection group, the expressions of calumenin and GRP78 mRNA in lentivirus infection miRNA378 silence group did not change insignificantly.

CONCLUSIONS

Adriamycin injection may cause expression of calumenin in suckling mouse myocardium with myocarditis reduced, which may lead to the endoplasmic reticulum stress. This effect is related with miRNA378.

[The effect of astragalus injection on the expression of endoplasmic reticulum stress chaperonin GRP78 and GRP94 mRNA in adriamycin-injured cardiomyocytes with calumenin silencing by shRNA]

OBJECTIVE

To investigate the effect of astragalus injection on the endoplasmic reticulum stress in adriamycin(ADR)-injured cardiomyocytes with calumenin silencing by shRNA.

METHODS

Firstly, the stable lentiviral calumenin shRNAvector was constructed. Secondly, in vitro cultured neonatal rat cardiac myocytes were randomly divided into control group、normal group (3 mg/L ADR), lentivirus infection group (lentivirus infection+3 mg/L ADR), Astragalus group 1 (3 mg/L ADR+Astragalus), Astragalus group 2 (lentivirus infection+3 mg/L ADR+Astragalus). The mRNA epression level of calumenin expression and reticulum stress chaperone in GRP78, GRP94 of each group was monitored by real-time PCR.

RESULTS

①Compared with that of the control group, the calumenin mRNA expression in the normal group was reduced(P<0.05), yet its mRNA level in lentivirus the infection group and the Astragalus group 2 was further reduced(P<0.01). Compared with that of the normal group, the mRNA contents of calumenin in the Astragalus group 1 was increased(P<0.05). The expression of calumenin in Astragalus group 2 was increased comparing with lentivirus infection group (P<0.01). ②Compared with that in the control group, the expression of reticulum stress chaperone in GRP78, GRP 94 in lentivirus infection group and normal group was significantly increased (P<0.01); Compared with that in the normal group, the expression of reticulum stress chaperone in GRP78, GRP94 in Astragalus group 1 was reduced(P<0.01); Compared with that in the lentivirus infection group, the expression of reticulum stress chaperone in GRP78, GRP94 in the Astragalus group 2 was obviously decreased(P<0.01).

CONCLUSIONS

①Calumenin can alleviate endoplasmic reticulum stress induced by ADR-injured myocardial cells. ②Astragalus injection can restrain the endoplasmic reticulum stress induced by adriamycin, which may be achieved by the calumenin protein.