Biological functions and role of CCN1/Cyr61 in embryogenesis and tumorigenesis in the female reproductive system (Review)

A single-cell atlas of the cycling murine ovary

The estrous cycle is regulated by rhythmic endocrine interactions of the nervous and reproductive systems, which coordinate the hormonal and ovulatory functions of the ovary. Folliculogenesis and follicle progression require the orchestrated response of a variety of cell types to allow the maturation of the follicle and its sequela, ovulation, corpus luteum formation, and ovulatory wound repair. Little is known about the cell state dynamics of the ovary during the estrous cycle and the paracrine factors that help coordinate this process. Herein, we used single-cell RNA sequencing to evaluate the transcriptome of >34,000 cells of the adult mouse ovary and describe the transcriptional changes that occur across the normal estrous cycle and other reproductive states to build a comprehensive dynamic atlas of murine ovarian cell types and states.

A Tissue Engineering Acoustophoretic (TEA) Set-up for the Enhanced Osteogenic Differentiation of Murine Mesenchymal Stromal Cells (mMSCs)

Quickly developing precision medicine and patient-oriented treatment strategies urgently require novel technological solutions. The randomly cell-populated scaffolds usually used for tissue engineering often fail to mimic the highly anisotropic characteristics of native tissue. In this work, an ultrasound standing-wave-based tissue engineering acoustophoretic (TEA) set-up was developed to organize murine mesenchymal stromal cells (mMSCs) in an in situ polymerizing 3-D fibrin hydrogel. The resultant constructs, consisting of 17 cell layers spaced at 300 µm, were obtained by continuous wave ultrasound applied at a 2.5 MHz frequency. The patterned mMSCs preserved the structured behavior within 10 days of culturing in osteogenic conditions. Cell viability was moderately increased 1 day after the patterning; it subdued and evened out, with the cells randomly encapsulated in hydrogels, within 21 days of culturing. Cells in the structured hydrogels exhibited enhanced expression of certain osteogenic markers, i.e., Runt-related transcription factor 2 (RUNX2), osterix (Osx) transcription factor, collagen-1 alpha1 (COL1A1), osteopontin (OPN), osteocalcin (OCN), and osteonectin (ON), as well as of certain cell-cycle-progression-associated genes, i.e., Cyclin D1, cysteine-rich angiogenic inducer 61 (CYR61), and anillin (ANLN), when cultured with osteogenic supplements and, for ANLN, also in the expansion media. Additionally, OPN expression was also augmented on day 5 in the patterned gels cultured without the osteoinductive media, suggesting the pro-osteogenic influence of the patterned cell organization. The TEA set-up proposes a novel method for non-invasively organizing cells in a 3-D environment, potentially enhancing the regenerative properties of the designed anisotropic constructs for bone healing.

Short-Term Hypoxia in Cells Induces Expression of Genes Which Are Enhanced in Stressed Cells

All living organisms must respond to, and defend against, environmental stresses. Depending on the extent and severity of stress, cells try to alter their metabolism and adapt to a new state. Changes in alternative splicing of pre-mRNA are a crucial regulation mechanism through which cells are able to respond to a decrease in oxygen tension in the cellular environment. Currently, only limited data are available in the literature on how short-term hypoxia influences mRNA isoform formation. In this work, we discovered that expressions of the same genes that are activated during cellular stress are also activated in cells under short-term hypoxic conditions. Our results demonstrate that short-term hypoxia influences the splicing of genes associated with cell stress and apoptosis; however, the mRNA isoform formation patterns from the same pre-mRNAs in cells under short-term hypoxic conditions and prolonged hypoxia are different. Obtained data also show that short-term cellular hypoxia increases protein phosphatase but not protein kinase expression. Enhanced levels of protein phosphatase expression in cells are clearly important for changing mRNA isoform formation.

Expression of Shh, Gli1, and Cyr61 in Gastric Cancer Predicts Overall Survival of Patients: A Retrospective Study

OBJECTIVE

This study aimed to evaluate the expression levels of Shh, Gli1, and Cyr61 proteins in gastric cancer tissues and analyze the relationship between these three proteins and the clinicopathological factors and prognosis of patients.

METHODS

This was a retrospective study. Four hundred gastric cancer tissue specimens from patients who underwent radical gastrectomy in Zhangye People's Hospital affiliated to Hexi University between February 2013 and February 2021 underwent immunohistochemical analysis.

RESULTS

The positive expression rates of Shh, Gli1, and Cyr61 in gastric cancer tissues were 55.5%, 56.5%, and 64.5%, respectively. The expressions of Shh, Gli1, and Cyr61 in gastric cancer tissues were significantly correlated with tumor size, depth of invasion, and degree of differentiation (P < .05). The expression of Shh protein was positively correlated with the expression of Gli1 protein (P < .01), and the expression of Gli1 protein was positively correlated with the expression of Cyr61 protein (P < .01). Univariate and multivariate analyses showed that the expression of Shh, Gli1, and Cyr61 could predict the prognosis of patients (P < .05). Receiver operating characteristic curve analysis combined with TNM staging could better predict the three-year overall survival of patients (P < .05).

CONCLUSION

Shh, Gli1, and Cyr61 proteins are significantly expressed in gastric cancer tissues and are risk factors for the prognosis of patients with gastric cancer.

Evaluation of Colocasia esculenta Schott in anti-cancerous properties with proximity extension assays

Background

Colocasia esculenta Schott (called as Xiangshayu in Chinese) is an excellent local cultivar of the genus polymorpha in Jiangsu Province, China.

Objective

In the present study, we have performed a comparative study before and after dietary consumption with Colocasia esculenta Schott to evaluate its anti-cancerous properties.

Design

Forty-two healthy volunteers were recruited, and dietary consumption with 200 g of tap water cooked Colocasia esculenta Schott daily was conducted for 1 month. Plasma samples from the subjects before and after dietary consumption with Colocasia esculenta Schott were analyzed with proximity extension assays for the alteration of 92 proteins in relation with cancers, while blood samples were examined for physiological parameters with an automatic biochemical analyzer. Bioinformatic analyses were conducted using MalaCards and GEPIA.

Results

After taking dietary consumption with Colocasia esculenta Schott, circulating CYR61, ANXA1, and VIM protein levels in the subjects was found to be most significantly downregulated, while for ITGB5, EPHA2, and CEACAM1, it was upregulated. Alternation of these proteins was predicted to be associated with the development of tumors such as pancreatic adenocarcinoma and breast and prostate cancers.

Conclusion

The present study provides evidence that Colocasia esculenta Schott, as a healthy food, has anti-cancerous properties. Further investigation of phytochemistry in Colocasia esculenta Schott has been taken into our consideration.

Bladder mesenchymal stromal cell-derived exosomal miRNA-217 modulates bladder cancer cell survival through Hippo-YAP pathway

BACKGROUND

Donor cell-derived exosomes regulate recipient cell functions. The aim of this study was to investigate the effect of human normal bladder stromal cell (hBSC) derived exosomal miR-217 on bladder cell cancer proliferation and migration.

METHODS

Human BSCs were transfected with miR-217 mimic or inhibitor and hBSC-derived exosomes were isolated. Human bladder cancer cell lines (T24 and 5367) were co-cultured with hBSC-derived exosomal miR-217 mimic or inhibitor. Proliferation, migration, and apoptosis of the bladder cancer cells were assessed by Edu assay, Transwell migration assay, and Annexin V assay.

RESULTS

Expression of miR-217 was significantly higher in the T24 and 5367 cell lines (P < 0.01). Exosomal miR-217 mimic enhanced proliferation and migration of T24 and 5367 cells, but inhibited apoptosis of the cells (P < 0.01); in contrast, exosomal miR-217 inhibitor suppressed proliferation and migration but stimulated apoptosis of the two cancer cell lines (P < 0.01). Moreover, exosomal miR-217 mimic stimulated YAP and its target proteins including Cyr61, CTGF, and ANKRD1 (P < 0.01), and in contrast, exosomal miR-217 inhibitor suppressed YAP and its target proteins (P < 0.01).

CONCLUSION

These findings suggested that hBSC-derived exosomal miR-217 may act as oncogene in bladder cancer cells, and that Hippo-YAP signaling pathway maybe the target for miR-217 in the bladder cancer cell lines.

Serum CYR61 as a potential biomarker for the diagnosis of esophagogastric junction tumor

BACKGROUND

Esophagogastric junction tumor (EGJ) is a rare but fatal disease with a rapid rising incidence worldwide in the late 20 years, and it lacks a convenient and safe method for diagnosis. The present study aimed to evaluate the potential of serum CYR61 as a biomarker for the diagnosis of EGJ tumor.

METHODS

Enzyme-linked immunosorbent assay (ELISA) was used to estimate CYR61 levels in sera of 152 EGJ tumor patients and 137 normal controls. Receiver operating characteristics (ROC) was carried out to evaluate the diagnostic accuracy. The Mann-Whitney's U test was used to compare the difference of serum levels of CYR61 between groups. And chi-square tests were employed to estimate the correlation of the positive rate of serum CYR61 between/among subgroups.

RESULTS

Serum CYR61 levels were statistically lower in EGJ tumor and early-stage EGJ tumor patients than those in normal controls (P<0.0001). The sensitivity, specificity and the area under the curve (AUC) of this biomarker in EGJ tumor were 88.2%, 43.8% and 0.691, respectively, and those for early stage of EGJ tumor were 80.0%, 66.4% and 0.722, respectively. Analyses showed that there was no correlation between the clinical data and the levels of CYR61 (P>0.05).

CONCLUSION

The present study showed that CYR61 might be a potential biomarker to assist the diagnosis of EGJ tumor.

The Phagocytic Code Regulating Phagocytosis of Mammalian Cells

Mammalian phagocytes can phagocytose (i.e. eat) other mammalian cells in the body if they display certain signals, and this phagocytosis plays fundamental roles in development, cell turnover, tissue homeostasis and disease prevention. To phagocytose the correct cells, phagocytes must discriminate which cells to eat using a 'phagocytic code' - a set of over 50 known phagocytic signals determining whether a cell is eaten or not - comprising find-me signals, eat-me signals, don't-eat-me signals and opsonins. Most opsonins require binding to eat-me signals - for example, the opsonins galectin-3, calreticulin and C1q bind asialoglycan eat-me signals on target cells - to induce phagocytosis. Some proteins act as 'self-opsonins', while others are 'negative opsonins' or 'phagocyte suppressants', inhibiting phagocytosis. We review known phagocytic signals here, both established and novel, and how they integrate to regulate phagocytosis of several mammalian targets - including excess cells in development, senescent and aged cells, infected cells, cancer cells, dead or dying cells, cell debris and neuronal synapses. Understanding the phagocytic code, and how it goes wrong, may enable novel therapies for multiple pathologies with too much or too little phagocytosis, such as: infectious disease, cancer, neurodegeneration, psychiatric disease, cardiovascular disease, ageing and auto-immune disease.

Identification of a tumor microenvironment-associated prognostic gene signature in bladder cancer by integrated bioinformatic analysis

Bladder cancer is a common malignancy in the urinary system. Stromal and immune cells in tumor microenvironments, including those in the bladder cancer microenvironment, can serve as prognostic markers. However, the complex processes of bladder cancer necessitate large-scale evaluation to better understand the underlying mechanisms and identify biomarkers for diagnosis and treatment. We used the Estimation of STromal and Immune cells in MAlignant Tumors using Expression data algorithm to assess the association between stromal and immune cell-related genes and overall survival of patients with bladder cancer. We also identified and evaluated differentially expressed genes between cancer and non-cancer tissues from The Cancer Genome Atlas. Patients were categorized into different prognosis groups according to their stromal/immune scores based on differential gene expression. In addition, the prognostic value of the differentially expressed genes was assessed in a separate validation cohort using the Gene Expression Omnibus microarray dataset GSE13507, which identified nine genes (TNC, CALD1, PALLD, TAGLN, TGFB1I1, HSPB6, RASL12, CPXM2, and CYR61) associated with overall survival. Multivariate regression analysis showed that three genes (TNC, CALD1, and PALLD) were possible independent prognostic markers for patients with bladder cancer. Multiple gene set enrichment analysis of individual genes showed strong correlations with stromal and immune interactions, indicating that these nine genes may be related to carcinogenesis, invasion, and metastasis of bladder cancer. These findings provide useful insight into the molecular mechanisms of bladder cancer development, and suggest candidate biomarkers for prognosis and treatment.

Cohesive cancer invasion of the biophysical barrier of smooth muscle

Smooth muscle is found around organs in the digestive, respiratory, and reproductive tracts. Cancers arising in the bladder, prostate, stomach, colon, and other sites progress from low-risk disease to high-risk, lethal metastatic disease characterized by tumor invasion into, within, and through the biophysical barrier of smooth muscle. We consider here the unique biophysical properties of smooth muscle and how cohesive clusters of tumor use mechanosensing cell-cell and cell-ECM (extracellular matrix) adhesion receptors to move through a structured muscle and withstand the biophysical forces to reach distant sites. Understanding integrated mechanosensing features within tumor cluster and smooth muscle and potential triggers within adjacent adipose tissue, such as the unique damage-associated molecular pattern protein (DAMP), eNAMPT (extracellular nicotinamide phosphoribosyltransferase), or visfatin, offers an opportunity to prevent the first steps of invasion and metastasis through the structured muscle.

Zika virus promotes CCN1 expression via the CaMKIIα-CREB pathway in astrocytes

Zika virus (ZIKV) infection in the human central nervous system (CNS) causes Guillain–Barre syndrome, cerebellum deformity, and other diseases. Astrocytes are immune response cells in the CNS and an important component of the blood–brain barrier. Consequently, any damage to astrocytes facilitates the spread of ZIKV in the CNS. Connective tissue growth factor/Nephroblastoma overexpressed gene family 1 (CCN1), an important inflammatory factor secreted by astrocytes, is reported to regulate innate immunity and viral infection. However, the mechanism by which astrocyte viral infection affects CCN1 expression remains undefined. In this study, we demonstrate that ZIKV infection up-regulates CCN1 expression in astrocytes, thus promoting intracellular viral replication. Other studies revealed that the cAMP response element (CRE) in the CCN1 promoter is activated by the ZIKV NS3 protein. The cAMP-responsive element-binding protein (CREB), a transacting factor of the CRE, is also activated by NS3 or ZIKV. Furthermore,a specific inhibitor of CREB, i.e. SGC-CBP30, reduced ZIKV-induced CCN1 up-regulation and ZIKV replication. Moreover, co-immunoprecipitation, overexpression, and knockdown studies confirmed that the interaction between NS3 and the regulatory domain of CaMKIIα could activate the CREB pathway, thus resulting in the up-regulation of CCN1 expression and enhancement of virus replication. In conclusion, the findings of our investigations on the NS3-CaMKIIα-CREB-CCN1 pathway provide a foundation for understanding the infection mechanism of ZIKV in the CNS.

Forkhead box K1 facilitates growth of papillary thyroid carcinoma cells by regulating connective tissue growth factor expression

Forkhead box (FOX) proteins have been identified as key transcription factors in diverse biological processes involved in tumor progression. A large number of FOX proteins are implicated in tumorigenesis of papillary thyroid carcinoma (PTC). Here we investigated the role of Forkhead box K1 (FOXK1) in PTC progression. First, we found that FOXK1 was elevated in both PTC tissues (N = 68) and cell lines. Moreover, up-regulated FOXK1 was associated with shorter overall survival of PTC patients. Second, in vitro functional assays showed that FOXK1 promoted progression of PTC. Mechanistically, FOXK1 could bind to the promoter of cysteine-rich angiogenic inducer 61 (CYR61) and regulate connective tissue growth factor (CTGF) expression through CYR61. Notably, over-expression of CTGF weakened suppression of PTC progression induced by FOXK1 knockdown. Finally, in vivo xenotransplant tumor model indicated that knockdown of FOXK1 suppressed PTC growth. In conclusion, our results indicate that FOXK1 exerts oncogenic roles in PTC via CYR61/CTGF axis, which suggests FOXK1 might act as a potential therapeutic target.

SMAD-dependent signaling mediates morphogenetic protein 6-induced stimulation of connective tissue growth factor in luteinized human granulosa cells†

Connective tissue growth factor (also known as CTGF or CCN2) is a secreted matricellular protein that belongs to the CCN family. With wide-ranging biological activities and tissue expression patterns, CTGF plays a critical role in regulating various cellular functions. In the female reproductive system, CTGF is highly expressed in granulosa cells in growing ovarian follicles and is involved in the regulation of follicular development, ovulation, and luteal function. In the mammalian ovary, bone morphogenetic protein 6 (BMP6) is an important intraovarian modulator of follicular development. In this study, we demonstrated that BMP6 treatment significantly increased the expression of CTGF in both primary and immortalized human granulosa cells. Using both pharmacological inhibitors and Small interfering RNA-mediated knockdown approaches, we showed that ALK2 and ALK3 type I receptors are required for BMP6-induced cellular activities. Furthermore, this effect is most likely mediated by a Sma- and Mad-related protein (SMAD)-dependent pathway. Our studies provide novel insight into the molecular mechanisms by which an intraovarian growth factor affects the production of another factor via a paracrine effect in human granulosa cells.

Pancreatic neuroendocrine tumors: Therapeutic challenges and research limitations

Pancreatic neuroendocrine tumors (PNETs) are known to be the second most common epithelial malignancy of the pancreas. PNETs can be listed among the slowest growing as well as the fastest growing human cancers. The prevalence of PNETs is deceptively low; however, its incidence has significantly increased over the past decades. According to the American Cancer Society’s estimate, about 4032 (> 7% of all pancreatic malignancies) individuals will be diagnosed with PNETs in 2020. PNETs often cause severe morbidity due to excessive secretion of hormones (such as serotonin) and/or overall tumor mass. Patients can live for many years (except for those patients with poorly differentiated G3 neuroendocrine tumors); thus, the prevalence of the tumors that is the number of patients actually dealing with the disease at any given time is fairly high because the survival is much longer than pancreatic ductal adenocarcinoma. Due to significant heterogeneity, the management of PNETs is very complex and remains an unmet clinical challenge. In terms of research studies, modest improvements have been made over the past decades in the identification of potential oncogenic drivers in order to enhance the quality of life and increase survival for this growing population of patients. Unfortunately, the majority of systematic therapies approved for the management of advanced stage PNETs lack objective response or at most result in modest benefits in survival. In this review, we aim to discuss the broad challenges associated with the management and the study of PNETs.

RU486 Metabolite Inhibits CCN1/Cyr61 Secretion by MDA-MB-231-Endothelial Adhesion

Successful adhesion of circulating tumor cells (CTCs) to microvascular endothelium of distant metastatic tissue is the key starting step of metastatic cascade that could be effectively chemoprevented as we demonstrated previously. Here, we hypothesize that the hetero-adhesion may produce secretory biomarkers that may be important for both premetastatic diagnosis and chemoprevention. We show that co-incubation of triple-negative breast cancer (TNBC) cell line MDA-MB-231 with human pulmonary microvascular endothelial monolayers (HPMEC) secretes Cyr61 (CCN1), primarily from MDA-MB-231. However, addition of metapristone (RU486 metabolite) to the co-incubation system inhibits Cyr61 secretion probably via the Cyr61/integrin αvβ1 signaling pathway without significant cytotoxicity on both MDA-MB-231 and HPMEC. Transfection of MDA-MB-231 with Cyr61-related recombinant plasmid or siRNA enhances or reduces Cyr61 expression, accordingly. The transfection significantly changes hetero-adhesion and migration of MDA-MB-231, and the changed bioactivities by overexpressed CYR61 could be antagonized by metapristone in vitro. Moreover, the circulating MDA-MB-231 develops lung metastasis in mice, which could be effectively prevented by oral metapristone without significant toxicity. The present study, for the first time, demonstrates that co-incubation of MDA-MB-231 with HPMEC secrets CYR61 probably via the CYR61/integrin α_vβ₁ signaling pathway to promote adhesion-invasion of TNBC (early metastatic step). Metapristone, by interfering the adhesion-invasion process, prevents metastasis from happening.

CCN2 Mediates S1P-Induced Upregulation of COX2 Expression in Human Granulosa-Lutein Cells

CCN1 and CCN2 are members of the CCN family and play essential roles in the regulation of multiple female reproductive functions, including ovulation. Cyclooxygenase-2 (COX2) is a critical mediator of ovulation and can be induced by sphingosine-1-phosphate (S1P) through the S1P_1/3-mediated Yes-associated protein (YAP) signaling. However, it is unclear whether CCN1 or CCN2 can mediate S1P-induced upregulation of COX2 expression and increase in prostaglandin E2 (PGE2) production in human granulosa-lutein (hGL) cells. In the present study, we investigated the effects of S1P on the expressions of CCN1 and CCN2 in hGL cells. Additionally, we used a dual inhibition approach (siRNA-mediated silencing and small molecular inhibitors) to investigate the molecular mechanisms of S1P effects. Our results showed that S1P treatment significantly upregulated the expression of CCN1 and CCN2 in a concentration-dependent manner in hGL cells. Additionally, inhibition or silencing of S1P₁, but not S1P₃, completely abolished the S1P-induced upregulation of CCN2 expression. Furthermore, we demonstrated that S1P-induced nuclear translocation of YAP and inhibition or silencing of YAP completely abolished the S1P-induced upregulation of CCN1 and CCN2 expression. Notably, silencing of CCN2, but not CCN1, completely reversed the S1P-induced upregulation of COX2 expression and the increase in PGE2 production. Thus, CCN2 mediates the S1P-induced upregulation of COX2 expression through the S1P₁-mediated signaling pathway in hGL cells. Our findings expand our understanding of the molecular mechanism underlying the S1P-mediated cellular activities in the human ovary.

Identification of the Transcriptional Networks and the Involvement in Angiotensin II-Induced Injury after CRISPR/Cas9-Mediated Knockdown of Cyr61 in HEK293T Cells

Background

The transcriptional networks of Cyr61 and its function in cell injury are poorly understood. The present study depicted the lncRNA and mRNA profiles and the involvement in angiotensin II-induced injury after Cyr61 knockdown mediated by CRISPR/Cas9 in HEK293T cells.

Methods

HEK293T cells were cultured, and Cyr61 knockdown was achieved by transfection of the CRISPR/Cas9 KO plasmid. lncRNA and mRNA microarrays were used to identify differentially expressed genes (DEGs). Gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to determine biofunctions and signaling pathways. RT-PCR was used to validate the microarray results. Cells were divided into four groups: control, Cyr61 knockdown, angiotensin II (Ang II) without Cyr61 knockdown, and Ang II with Cyr61 knockdown. CCK8, western blotting, and flow cytometry analysis were carried out to dissect cellular function.

Results

A total of 23184 lncRNAs and 28264 mRNAs were normalized. 26 lncRNAs and 212 mRNAs were upregulated, and 74 lncRNAs and 233 mRNAs were downregulated after Cyr61 knockdown. Analysis of cellular components, molecular functions, biological processes, and regulatory pathways associated with the differentially expressed mRNAs revealed downstream mechanisms of the Cyr61 gene. The differentially expressed genes were affected for small cell lung cancer, axon guidance, Fc gamma R-mediated phagocytosis, MAPK signaling pathway, focal adhesion, insulin resistance, and metabolic pathways. In addition, Cyr61 expression was increased in accordance with induction of cell cycle arrest and apoptosis and inhibition of cell proliferation induced by Ang II. Knockdown of Cyr61 in HEK293T cells promoted cell cycle procession, decreased apoptosis, and promoted cell proliferation.

Conclusions

The Cyr61 gene is involved in Ang II-induced injury in HEK293T cells. Functional mechanisms of the differentially expressed lncRNAs and mRNAs as well as identification of metabolic pathways will provide new therapeutic targets for Cyr61-realated diseases.