C1ql1/Ctrp14 and C1ql4/Ctrp11 promote angiogenesis of endothelial cells through activation of ERK1/2 signal pathway

CTRP13-Mediated Effects on Endothelial Cell Function and Their Potential Role in Obesity

BACKGROUND

Obesity, a major component of cardiometabolic syndrome, contributes to the imbalance between pro- and anti-atherosclerotic factors via dysregulation of adipocytokine secretion. Among these adipocytokines, the C1q/TNF-related proteins (CTRPs) play a role in the modulation of atherosclerosis development and progression. Here, we investigated the vascular effects of CTRP13.

RESULTS

CTRP13 is not only expressed in adipose tissue but also in vessels/endothelial cells (ECs) of mice, rats, and humans. Obese individuals (mice, rats, and humans) showed higher vascular CTRP13 expression. Human Umbilical Vein Endothelial Cells (HUVECs), cultured in the presence of serum from obese mice, mimicked this obesity-associated effect on CTRP13 protein expression. Similarly, high glucose conditions and TNF-alpha, but not insulin, resulted in a strong increase in CTRP13 in these cells. Recombinant CTRP13 induced a reduction in EC proliferation via AMPK. In addition, CTRP13 reduced cell cycle progression and increased p53 phosphorylation and p21 protein expression, but reduced Rb phosphorylation, with the effects largely depending on alpha-2 AMPK as suggested by adenoviral overexpression of dominant-negative (DN) or wild-type (WT) alpha 1/alpha 2 AMPK.

CONCLUSION

The present study demonstrates that CTRP13 expression is induced in ECs under diabetic conditions and that CTRP13 possesses significant vaso-modulatory properties which may have an impact on vascular disease progression in patients.

Cardiac biopsies reveal differences in transcriptomics between left and right ventricle in patients with or without diagnostic signs of heart failure

New or mild heart failure (HF) is mainly caused by left ventricular dysfunction. We hypothesised that gene expression differ between the left (LV) and right ventricle (RV) and secondly by type of LV dysfunction. We compared gene expression through myocardial biopsies from LV and RV of patients undergoing elective coronary bypass surgery (CABG). Patients were categorised based on LV ejection fraction (EF), diastolic function and NT-proBNP into pEF (preserved; LVEF ≥ 45%), rEF (reduced; LVEF < 45%) or normal LV function. Principal component analysis of gene expression displayed two clusters corresponding to LV and RV. Up-regulated genes in LV included natriuretic peptides NPPA and NPPB, transcription factors/coactivators STAT4 and VGLL2, ion channel related HCN2 and LRRC38 associated with cardiac muscle contraction, cytoskeleton, and cellular component movement. Patients with pEF phenotype versus normal differed in gene expression predominantly in LV, supporting that diastolic dysfunction and structural changes reflect early LV disease in pEF. DKK2 was overexpressed in LV of HFpEF phenotype, potentially leading to lower expression levels of β-catenin, α-SMA (smooth muscle actin), and enhanced apoptosis, and could be a possible factor in the development of HFpEF. CXCL14 was down-regulated in both pEF and rEF, and may play a role to promote development of HF.

Association between plasma CTRPs with cognitive impairment and neurodegeneration of Alzheimer's disease

AIMS

Recent evidence indicated the biological basis of complement 1q (C1q)/tumor necrosis factor (TNF)-related protein (CTRP) 3, 4, and 14 for affecting brain structure and cognitive function. Thus, we aimed to investigate the association between plasma CTRPs with Alzheimer's disease (AD).

METHODS

A multicenter, cross-sectional study recruited patients with AD (n = 137) and cognitively normal (CN) controls (n = 140). After the data collection of demographic characteristics, lifestyle risk factors, and medical history, plasma levels of tau phosphorylated at threonine 217 (pT217), pT181, neurofilament light (NfL), CTRP3, 4, and 14 were examined and compared. Multivariate logistic regression analysis was applied to determine associations of plasma CTPRs with the presence of AD. The correlation analysis was used to explore correlations between plasma CTPRs with scores of Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Activities of Daily Living (ADL) scale, and Clinical Dementia Rating Sum of Boxes (CDR-SB), and levels of plasma pT217, pT181, and NfL. Receiver-operating characteristic (ROC) analysis and Delong's test were used to determine the diagnostic power of plasma CTPRs.

RESULTS

Plasma levels of CTRP3, 4, and 14 were higher in AD group than those in CN group. After adjusting for conventional risk factors, CTRP3, CTRP4, and CTRP14 were associated with the presence of AD. In AD patients, CTRP3 was negatively correlated with scores of MMSE and MoCA, while positively correlated with ADL score, CDR-SB score, pT217, and pT181; CTRP4 was positively correlated with CDR-SB score, pT181, and NfL; CTRP14 was negatively correlated with MMSE score, while positively correlated with CDR-SB score, pT217, and NfL. An independent addition of CTRP3 and 4 to the basic model combining age, sex, years of education, APOE4 status, BMI, TG, and HDL-C led to a significant improvement in diagnostic power for AD, respectively.

CONCLUSIONS

All the findings preliminarily uncovered associations between plasma CTRPs and AD and suggested the potential of CTRPs as a blood-derived biomarker for AD.

Single-cell RNA sequencing reveals the transcriptional heterogeneity of Tbx18-positive cardiac cells during heart development

The T-box family transcription factor 18 (Tbx18) has been found to play a critical role in regulating the development of the mammalian heart during the primary stages of embryonic development while the cellular heterogeneity and landscape of Tbx18-positive (Tbx18+) cardiac cells remain incompletely characterized. Here, we analyzed prior published single-cell RNA sequencing (scRNA-seq) mouse heart data to explore the heterogeneity of Tbx18+ cardiac cell subpopulations and provide a comprehensive transcriptional landscape of Tbx18+ cardiac cells during their development. Bioinformatic analysis methods were utilized to identify the heterogeneity between cell groups. Based on the gene expression characteristics, Tbx18+ cardiac cells can be classified into a minimum of two distinct cell populations, namely fibroblast-like cells and cardiomyocytes. In terms of temporal heterogeneity, these cells exhibit three developmental stages, namely the MEM stage, ML_P0 stage, and P stage Tbx18+ cardiac cells. Furthermore, Tbx18+ cardiac cells encompass several cell types, including cardiac progenitor-like cells, cardiomyocytes, and epicardial/stromal cells, as determined by specific transcriptional regulatory networks. The scRNA-seq results revealed the involvement of extracellular matrix (ECM) signals and epicardial epithelial-to-mesenchymal transition (EMT) in the development of Tbx18+ cardiac cells. The utilization of a lineage-tracing model served to validate the crucial function of Tbx18 in the differentiation of cardiac cells. Consequently, these findings offer a comprehensive depiction of the cellular heterogeneity within Tbx18+ cardiac cells.

Multi-faceted roles of C1q/TNF-related proteins family in atherosclerosis

Purpose of review

C1q/TNF-related proteins (CTRPs) are involved in the modulation of the development and prognosis of atherosclerosis (AS). Here, we summarizes the pathophysiological roles of individual members of the CTRP superfamily in the development of AS. Currently, there is no specific efficacious treatment for AS-related diseases, therefore it is urgent to develop novel therapeutic strategies aiming to target key molecules involved in AS.

Recent findings

Recently, mounting studies verified the critical roles of the CTRP family, including CTRP1-7, CTRP9 and CTRP11-15, in the development and progression of AS by influencing inflammatory response, modulating glucose and lipid metabolism, regulating endothelial functions and the proliferation of vascular smooth muscle cells (VSMCs).

Conclusions

CTRP family regulate different pathophysiology stages of AS. CTRP3, CTRP9, CTRP12, CTRP13 and CTRP15 play a clear protective role in AS, while CTRP5 and CTRP7 play a pro-atherosclerotic role in AS. The remarkable progress in our understanding of CTRPs' role in AS will provide an attractive therapeutic target for AS.

C1ql4 regulates breast cancer cell stemness and epithelial-mesenchymal transition through PI3K/AKT/NF-κB signaling pathway

Background

The stemness characteristic of breast cancer (BC) is a crucial factor underlying cancer recurrence and metastasis after operative therapy and chemoradiotherapy. Understanding the potential mechanism of breast cancer stem cells (BCSCs) may ameliorate the prognosis of patients.

Methods

We collected clinical specimens of BC patients for staining and statistical analysis to verify the expression status and clinical significance of complement C1q-like 4 (C1ql4). Western blot and qRT-PCR were employed to detect the expression of molecules. Flow cytometry was used to examine cell cycle, cell apoptosis and the portion of BCSCs. Wound healing and Transwell assays were used to detect cell metastasis. The effect of C1ql4 on breast cancer progression in vivo was examined in a nude mouse tumor bearing model.

Results

Our clinical analysis showed that C1ql4 was highly expressed in BC tissues and cell lines, and the high expression of C1ql4 was significantly corelated with the malignancy of BC patients. Moreover, we also found that C1ql4 was overexpressed in BCSCs. C1ql4 knockdown suppressed the BCSC and EMT properties, promoted cell cycle progression, enhanced BC cell apoptosis, and inhibited cell migration and invasion, whereas the C1ql4 overexpression exhibited the opposite effects. Mechanistically, C1ql4 promoted the activation and nuclear location of NF-κB and the expression of downstream factors TNF-α and IL-1β. Moreover, inhibition of PI3K/AKT signaling suppressed the C1ql4-induced stemness and EMT.

Conclusions

Our findings suggest that C1ql4 promotes the BC cell stemness and EMT via modulating the PI3K/AKT/NF-κB signaling, and provides a promising target for BC treatment.

Pleiotropy of C1QL proteins across physiological systems and their emerging role in synapse homeostasis

The C1q/TNF superfamily of proteins engages in a pleiotropy of physiological functions associated with various diseases. C1QL proteins demonstrate important protective and regulatory roles in the endocrine, immune, cardiovascular, and nervous systems in both human and rodent studies. Studies in the central nervous system (CNS), adipose, and muscle tissue reveal several C1QL protein and receptor pathways altering multiple cellular responses, including cell fusion, morphology, and adhesion. This review examines C1QL proteins across these systems, summarizing functional and disease associations and highlighting cellular responses based on in vitro and in vivo data, receptor interaction partners, and C1QL-associated protein signaling pathways. We highlight the functions of C1QL proteins in organizing CNS synapses, regulating synapse homeostasis, maintaining excitatory synapses, and mediating signaling and trans-synaptic connections. Yet, while these associations are known, present studies provide insufficient insight into the underlying molecular mechanism of their pleiotropy, including specific protein interactions and functional pathways. Thus, we suggest several areas for more in-depth and interdisciplinary hypothesis testing.

Complement 1q/Tumor Necrosis Factor-Related Proteins (CTRPs): Structure, Receptors and Signaling

Adiponectin and the other 15 members of the complement 1q (C1q)/tumor necrosis factor (TNF)-related protein (CTRP) family are secreted proteins composed of an N-terminal variable domain followed by a stalk region and a characteristic C-terminal trimerizing globular C1q (gC1q) domain originally identified in the subunits of the complement protein C1q. We performed a basic PubMed literature search for articles mentioning the various CTRPs or their receptors in the abstract or title. In this narrative review, we briefly summarize the biology of CTRPs and focus then on the structure, receptors and major signaling pathways of CTRPs. Analyses of CTRP knockout mice and CTRP transgenic mice gave overwhelming evidence for the relevance of the anti-inflammatory and insulin-sensitizing effects of CTRPs in autoimmune diseases, obesity, atherosclerosis and cardiac dysfunction. CTRPs form homo- and heterotypic trimers and oligomers which can have different activities. The receptors of some CTRPs are unknown and some receptors are redundantly targeted by several CTRPs. The way in which CTRPs activate their receptors to trigger downstream signaling pathways is largely unknown. CTRPs and their receptors are considered as promising therapeutic targets but their translational usage is still hampered by the limited knowledge of CTRP redundancy and CTRP signal transduction.

C1QL1/CTRP14 Is Largely Dispensable for Atherosclerosis Formation in Apolipoprotein-E-Deficient Mice

The purpose of this study was to investigate the influence of C1QL1 on atherosclerosis as well as the transcriptomic alteration of the aorta. While complement C1ql-like 1 (C1QL1) is one of the C1q/tumor-necrosis-factor-related protein (CTRP) family members, also known as CTRP14, and is synthesized and secreted mainly by the brain and adipose tissues, the functional properties of the C1QL1/CTRP14 protein outside the brain and adipocytes remain, however, unknown. In this regard, apolipoprotein E (ApoE) knockout (KO) mice were fed a Western diet and injected with adenovirus (Ad) green fluorescent protein or Ad-C1QL1 through the tail vein for 12 weeks. In contrast with the control cohort, the area of atherosclerotic plaque in ApoE KO mice overexpressing C1QL1 showed no significant difference, and the RNA sequence revealed that there were only 111 differentially expressed genes (DEGs) enriched in 26 signaling pathways of the mRNA profile in the aortic atherosclerosis lesions. This analysis also revealed the expression of several genes related to metabolism, organismal system, and human diseases such as type II diabetes, which are not associated with the formation of atherosclerosis in the aorta. These findings illustrate that C1QL1 is largely dispensable for atherosclerosis formation in ApoE-deficient mice and does not improve atherosclerotic plaque formation in the aorta.

CTRP11 contributes modestly to systemic metabolism and energy balance

C1q/TNF‐related proteins (CTRP1‐15) constitute a conserved group of secreted proteins of the C1q family with diverse functions. In vitro studies have shown that CTRP11/C1QL4 can inhibit adipogenesis, antagonize myoblast fusion, and promote testosterone synthesis and secretion. Whether CTRP11 is required for these processes in vivo remains unknown. Here, we show that knockout (KO) mice lacking CTRP11 have normal skeletal muscle mass and function, and testosterone level, suggesting that CTRP11 is dispensable for skeletal muscle development and testosterone production. We focused our analysis on whether this nutrient‐responsive secreted protein plays a role in controlling sugar and fat metabolism. At baseline when mice are fed a standard chow, CTRP11 deficiency affects metabolic parameters in a sexually dimorphic manner. Only Ctrp11‐KO female mice have significantly higher fasting serum ketones and reduced physical activity. In the refeeding phase following food withdrawal, Ctrp11‐KO female mice have reduced food intake and increased metabolic rate and energy expenditure, highlighting CTRP11’s role in fasting–refeeding response. When challenged with a high‐fat diet to induce obesity and metabolic dysfunction, CTRP11 deficiency modestly exacerbates obesity‐induced glucose intolerance, with more pronounced effects seen in Ctrp11‐KO male mice. Switching to a low‐fat diet after obesity induction results in greater fat loss in wild type relative to KO male mice, suggesting impaired response to obesity reversal and reduced metabolic flexibility in the absence of CTRP11. Collectively, our data provide genetic evidence for novel sex‐dependent metabolic regulation by CTRP11, but note the overall modest contribution of CTRP11 to systemic energy homeostasis.

Brain vasculature disturbance in schizophrenia

PURPOSE OF REVIEW

The vascular hypothesis of schizophrenia (SZ) postulates that brain endothelial dysfunction contributes to brain pathophysiology. This review discusses recent evidence for and against this hypothesis, including data related to blood-brain barrier (BBB), brain endothelium, and brain blood supply, to provide a critical weighed update.

RECENT FINDINGS

Different studies report a consistent proportion of SZ patients showing increased BBB permeability, reflected by higher levels of albumin in the cerebral spinal fluid. Of note, this was not a result of antipsychotic medication. The high inflammatory profile observed in some SZ patients is strongly associated with increased BBB permeability to circulating immune cells, and with more severe cognitive deficiencies. Also, sex was found to interact with BBB integrity and permeability in SZ. The strongest independent genetic association with SZ has been identified in FZD1, a hypoxia-response gene that is 600-fold higher expressed in early development endothelium as compared to adult brain endothelium. Regarding brain blood supply, there is evidence to suggest alterations in proper brain perfusion in SZ. Nonetheless, ex-vivo experiments suggested that widely used antipsychotics favor vasoconstriction; thus, alterations in cerebral perfusion might be related to the patients' medication.

SUMMARY

In some patients with SZ, a vulnerable brain endothelium may be interacting with environmental stressors, such as inflammation or hypoxia, converging into a more severe SZ symptomatology. Gene expression and performance of human brain endothelium could vary along with development and the establishment of the BBB; therefore, we encourage to investigate its possible contribution to SZ considering this dynamic context.

C1q tumor necrosis factor-related protein 1: a promising therapeutic target for atherosclerosis

ABSTRACT

Atherosclerosis serves as the pathological basis of most cardiovascular and cerebrovascular diseases. C1q tumor necrosis factor-related protein (CTRP1) is a 35-kDa glycoprotein synthesized by various tissues and cells, such as adipose tissue and macrophages. As an adiponectin paralog, CTRP1 signals through adiponectin receptor 1 (AdipoR1) and participates in a variety of pathophysiological processes. Circulating CTRP1 levels are significantly increased in patients with coronary artery disease. Importantly, CTRP1 was shown to accelerate the development of atherosclerosis by promoting vascular inflammation, macrophage foam cell formation and endothelial barrier dysfunction. This review focused on recent advances regarding the role of CTRP1 in atherogenesis with an emphasis on its potential as a novel biomarker and a promising therapeutic target for atherosclerosis-related diseases.

A novel injury site-natural antibody targeted complement inhibitor protects against lung transplant injury

Complement is known to play a role in ischemia and reperfusion injury (IRI). A general paradigm is that complement is activated by self-reactive natural IgM antibodies (nAbs), after they engage postischemic neoepitopes. However, a role for nAbs in lung transplantation (LTx) has not been explored. Using mouse models of LTx, we investigated the role of two postischemic neoepitopes, modified annexin IV (B4) and a subset of phospholipids (C2), in LTx. Antibody deficient Rag1-/- recipient mice were protected from LTx IRI. Reconstitution with either B4 or C2nAb restored IRI, with C2 significantly more effective than B4 nAb. Based on these information, we developed/characterized a novel complement inhibitor composed of single-chain antibody (scFv) derived from the C2 nAb linked to Crry (C2scFv-Crry), a murine inhibitor of C3 activation. Using an allogeneic LTx, in which recipients contain a full nAb repertoire, C2scFv-Crry targeted to the LTx, inhibited IRI, and delayed acute rejection. Finally, we demonstrate the expression of the C2 neoepitope in human donor lungs, highlighting the translational potential of this approach.

C1q-like 1 is frequently up-regulated in lung adenocarcinoma and contributes to the proliferation and invasion of tumor cells

This study aims to investigate the effects of C1q-like 1 (C1QL1) on the growth and migration of lung adenocarcinoma (LUAD) cells and the underlying mechanism. The expression of C1QL1 in LUAD tissues and its prognostic value were analyzed using the data from The Cancer Genome Atlas (TCGA) database. To investigate the function of C1QL1, loss-of-function and gain-of-function assays were conducted in Calu-3 cells and LTEP-a-2 cells, respectively. Cell growth was evaluated by CCK-8 and colony formation assays. Transwell assays were performed to assess cell invasive and migratory abilities. qRT-PCR and Western blotting were performed to detect RNA and protein expression, respectively. Firstly, we found that C1QL1 was highly expressed and predicted poor outcomes in LUAD patients from TCGA database. Moreover, the mRNA and protein expression levels of C1QL1 were higher in LUAD cells than that in normal lung cells. Results of functional experiments illustrated that depletion of C1QL1 restrained the growth, invasion and migration of Calu-3 cells, meanwhile over-expression of C1QL1 presented the opposite results in LTEP-a-2 cells. Furthermore, we discovered that down-regulation of C1QL1 elevated the protein level of E-cadherin and reduced the protein levels of N-cadherin, Vimentin and Snail in Calu-3 cells, whereas over-expression of C1QL1 led to the opposite outcomes in LTEP-a-2 cells. Our data indicated that C1QL1 functioned as a crucial driver in LUAD cell growth and motility, which might be achieved by modulating epithelial-mesenchymal transition (EMT). These consequences are of important relevance for the design of therapeutic strategies for LUAD.

Identification of Novel Molecular Markers of Human Th17 Cells

Th17 cells are important players in host defense against pathogens such as Staphylococcus aureus, Candida albicans, and Bacillus anthracis. Th17 cell-mediated inflammation, under certain conditions in which balance in the immune system is disrupted, is the underlying pathogenic mechanism of certain autoimmune disorders, e.g., rheumatoid arthritis, Graves' disease, multiple sclerosis, and psoriasis. In the present study, using transcriptomic profiling, we selected genes and analyzed the expression of these genes to find potential novel markers of Th17 lymphocytes. We found that APOD (apolipoprotein D); C1QL1 (complement component 1, Q subcomponent-like protein 1); and CTSL (cathepsin L) are expressed at significantly higher mRNA and protein levels in Th17 cells than in the Th1, Th2, and Treg subtypes. Interestingly, these genes and the proteins they encode are well associated with the function of Th17 cells, as these cells produce inflammation, which is linked with atherosclerosis and angiogenesis. Furthermore, we found that high expression of these genes in Th17 cells is associated with the acetylation of H2BK12 within their promoters. Thus, our results provide new information regarding this cell type. Based on these results, we also hope to better identify pathological conditions of clinical significance caused by Th17 cells.

Expression patterns of C1ql4 and its cell-adhesion GPCR Bai3 in the murine testis and functional roles in steroidogenesis

C1q-like 4 (C1QL4), a novel member of the C1q- and TNF-related protein family, was found to be highly expressed in rodent and human testis. However, the localization, developmental, and hormonally regulated expression and biologic function of C1ql4 in the testis have not been investigated. Here, we demonstrated that C1ql4 mRNA and protein levels in murine testes gradually increased from the postnatal period to the adult stage and were up-regulated by LH in vivo. In situ hybridization demonstrated that the distribution and expression levels of C1ql4 mRNA varied at different developmental stages, although C1ql4 mRNA was detected in the seminiferous tubule and interstitial Leydig cells. Recombinant C1QL4 did not affect cell proliferation but did increase testosterone production in TM3 Leydig cells, as well as in cultured seminiferous tubules. C1QL4-induced testosterone secretion in Leydig cells was accompanied by increased expression of steroidogenic acute regulatory (StAR) protein and steroidogenic enzymes. During this process, the c-Raf/extracellular signal-regulated protein kinase kinases 1 and 2/ERK1/2/mitogen- and stress-activated protein kinase-1 and cAMP/PKA/cAMP-responsive element binding protein signaling cascades were activated by C1QL4. The cell-adhesion GPCR brain-specific angiogenesis inhibitor 3 (BAI3), a putative receptor of C1QL4, was detected in the seminiferous tubule and interstitial Leydig cells during testicular development. Knockdown of Bai3 expression in Leydig cells led to a reduction in Star expression, accompanied by increases in phosphorylation of ERK1/2 and intercellular cAMP levels. However, C1QL4-induced StAR expression was not completely suppressed in the Bai3-deficient Leydig cells, and phosphorylation of ERK1/2 and intercellular cAMP levels were not significantly changed before and after C1QL4 stimulation. Our results suggested that although BAI3 played a role in C1QL4-induced steroidogenesis, there was an unidentified receptor that mediated C1QL4-activated testosterone secretion in Leydig cells through phosphorylation of ERK1/2 and up-regulation of intracellular cAMP levels. Taken together, our results showed, for the first time to our knowledge, that C1QL4 served as a novel acute regulator of testosterone secretion, and BAI3 functioned as a new receptor that is involved in steroidogenesis in Leydig cells. BAI3-independent ERK1/2 activation and cAMP activation mediated C1QL4-induced testosterone secretion. This study expanded the reproductive roles and mechanisms of C1QL4 and BAI3 signaling pathways.-Tan, A., Ke, S., Chen, Y., Chen, L., Lu, X., Ding, F., Yang, L., Tang, Y., Yu, Y. Expression patterns of C1ql4 and its cell-adhesion GPCR Bai3 in the murine testis and functional roles in steroidogenesis.

The Impact of Aging on Adipose Function and Adipokine Synthesis

During the last 40 years, there has been a world-wide increase in both the prevalence of obesity and an increase in the number of persons over the age of 60 due to a decline in deaths from infectious disease and the nutrition transition in low and middle income nations. While the increase in the elderly population indicates improvements in global public health, this population may experience a diminished quality of life due to the negative impacts of obesity on age-associated inflammation. Aging alters adipose tissue composition and function resulting in insulin resistance and ectopic lipid storage. A reduction in brown adipose tissue activity, declining sex hormones levels, and abdominal adipose tissue expansion occur with advancing years through the redistribution of lipids from the subcutaneous to the visceral fat compartment. These changes in adipose tissue function and distribution influence the secretion of adipose tissue derived hormones, or adipokines, that promote a chronic state of low-grade systemic inflammation. Ultimately, obesity accelerates aging by enhancing inflammation and increasing the risk of age-associated diseases. The focus of this review is the impact of aging on adipose tissue distribution and function and how these effects influence the elaboration of pro and anti-inflammatory adipokines.

Effect of cell-phone radiofrequency on angiogenesis and cell invasion in human head and neck cancer cells

BACKGROUND

Today, the cell phone is the most widespread technology globally. However, the outcome of cell-phone radiofrequency on head and neck cancer progression has not yet been explored.

METHODS

The chorioallantoic membrane (CAM) and human head and neck cancer cell lines, FaDu and SCC25, were used to explore the outcome of cell-phone radiofrequency on angiogenesis, cell invasion, and colony formation of head and neck cancer cells, respectively. Western blot analysis was used to investigate the impact of the cell phone on the regulation of E-cadherin and Erk1/Erk2 genes.

RESULTS

Our data revealed that cell-phone radiofrequency promotes angiogenesis of the CAM. In addition, the cell phone enhances cell invasion and colony formation of human head and neck cancer cells; this is accompanied by a downregulation of E-cadherin expression. More significantly, we found that the cell phone can activate Erk1/Erk2 in our experimental models.

CONCLUSION

Our investigation reveals that cell-phone radiofrequency could enhance head and neck cancer by stimulating angiogenesis and cell invasion via Erk1/Erk2 activation.