Depletion of mitochondrial reactive oxygen species downregulates epithelial-to-mesenchymal transition in cervical cancer cells

Effect of Regular Consumption of a Miraculin-Based Food Supplement on Taste Perception and Nutritional Status in Malnourished Cancer Patients: A Triple-Blind, Randomized, Placebo-Controlled Clinical Trial-CLINMIR Pilot Protocol

Taste disorders are common among cancer patients undergoing chemotherapy, with a prevalence ranging from 20% to 86%, persisting throughout treatment. This condition leads to reduced food consumption, increasing the risk of malnutrition. Malnutrition is associated not only with worse treatment efficacy and poor disease prognosis but also with reduced functional status and quality of life. The fruit of Synsepalum dulcificum (Daniell), commonly known as miracle berry or miracle fruit, contains miraculin, a taste-modifying protein with profound effects on taste perception. The CLINMIR Protocol is a triple-blind, randomized, placebo-controlled clinical trial designed to evaluate the regular consumption of a food supplement containing a miraculin-based novel food, dried miracle berry (DMB), on the taste perception (measured through electrogustometry) and nutritional status (evaluated through the GLIM Criteria) of malnourished cancer patients under active antineoplastic treatment. To this end, a pilot study was designed with 30 randomized patients divided into three study arms (150 mg DMB + 150 mg freeze-dried strawberries, 300 mg DMB, or placebo) for three months. Throughout the five main visits, an exhaustive assessment of different parameters susceptible to improvement through regular consumption of the miraculin-based food supplement will be conducted, including electrical and chemical taste perception, smell perception, nutritional and morphofunctional assessment, diet, quality of life, the fatty acid profile of erythrocytes, levels of inflammatory and cancer-associated cytokines, oxidative stress, antioxidant defense system, plasma metabolomics, and saliva and stool microbiota. The primary anticipated result is that malnourished cancer patients with taste distortion who consume the miraculin-based food supplement will report an improvement in food taste perception. This improvement translates into increased food intake, thereby ameliorating their nutritional status and mitigating associated risks. Additionally, the study aims to pinpoint the optimal dosage that provides maximal benefits. The protocol adheres to the SPIRIT 2013 Statement, which provides evidence-based recommendations and is widely endorsed as an international standard for trial protocols. The clinical trial protocol has been registered at the platform for Clinical Trials (NCT05486260).

Current perspectives of mitochondria-targeted antioxidants in cancer prevention and treatment

Oxidative stress nearly always accompanies all stages of cancer development. At the early stages, antioxidants may help to reduce reactive oxygen species (ROS) production and exhibit anticarcinogenic effects. In the later stages, ROS involvement becomes more complex. On the one hand, ROS are necessary for cancer progression and epithelial-mesenchymal transition. On the other hand, antioxidants may promote cancer cell survival and may increase metastatic frequency. The role of mitochondrial ROS in cancer development remains largely unknown. This paper reviews experimental data on the effects of both endogenous and exogenous antioxidants on cancerogenesis focusing on the development and application of mitochondria-targeted antioxidants. We also discuss the prospects for antioxidant cancer therapy, focusing on the use of mitochondria-targeted antioxidants.

Expression of HIF-1α and Genes Involved in Glucose Metabolism Is Increased in Cervical Cancer and HPV-16-Positive Cell Lines

Cervical cancer (CC) is the most common cancer in women in the lower genital tract. The main risk factor for developing CC is persistent infection with HPV 16. The E6 and E7 oncoproteins of HPV 16 have been related to metabolic reprogramming in cancer through the regulation of the expression and stability of HIF-1α and consequently of the expression of its target genes, such as HIF1A (HIF-1α), SLC2A1 (GLUT1), LDHA, CA9 (CAIX), SLC16A3 (MCT4), and BSG (Basigin or CD147), which are involved in glucose metabolism. This work aimed to evaluate the expression of HIF-1α, GLUT1, LDHA, CAIX, MCT4, and Basigin in patient samples and CC cell lines. To evaluate the expression level of HIF1A, SLC2A1, LDHA, CA9, SLC16A3, and BSG genes in tissue from patients with CC and normal tissue, the TCGA dataset was used. To evaluate the expression level of these genes by RT-qPCR in CC cell lines, HPV-negative (C-33A) and HPV-16-positive (SiHa and Ca Ski) cell lines were used. Increased expression of HIF1A, SLC2A1, LDHA, SLC16A3, and BSG was found in Ca Ski and CA9 in SiHa compared to C-33A. Similar results were observed in CC tissues compared to normal tissue obtained by bioinformatics analysis. In conclusion, the expression of HIF-1α, GLUT1, LDHA, CAIX, MCT4, and BSG genes is increased in CC and HPV-16-positive cell lines.

Mitochondria-targeted antioxidant SkQ1 inhibits leukotriene synthesis in human neutrophils

Leukotrienes are among the most potent mediators of inflammation, and inhibition of their biosynthesis, is becoming increasingly important in the treatment of many pathologies. In this work, we demonstrated that preincubation of human neutrophils with the mitochondria targeted antioxidant SkQ1 (100 nM) strongly inhibits leukotriene synthesis induced by three different stimuli: the Ca²⁺ ionophore A23187, the chemotactic formyl-peptide fMLP in combination with cytocholasin B, and opsonized zymosan. The SkQ1 analogue lacking the antioxidant quinone moiety (C12TPP) was ineffective, suggesting that mitochondrial production of reactive oxygen species (ROS) is critical for activating of leukotriene synthesis in human neutrophils. The uncoupler of oxidative phosphorylation FCCP also inhibits leukotriene synthesis, indicating that a high membrane potential is a prerequisite for stimulating leukotriene synthesis in neutrophils. Our data show that activation of mitogen-activated protein kinases p38 and ERK1/2, which is important for leukotriene synthesis in neutrophils is a target for SkQ1: 1) the selective p38 inhibitor SB203580 inhibited fMLP-induced leukotriene synthesis, while the ERK1/2 activation inhibitor U0126 suppressed leukotriene synthesis induced by any of the three stimuli; 2) SkQ1 effectively prevents p38 and ERK1/2 activation (accumulation of phosphorylated forms) induced by all three stimuli. This is the first study pointing to the involvement of mitochondrial reactive oxygen species in the activation of leukotriene synthesis in human neutrophils. The use of mitochondria-targeted antioxidants can be considered as a promising strategy for inhibiting leukotriene synthesis and treating various inflammatory pathologies.

Targeting Mitochondrial ROS Production to Reverse the Epithelial-Mesenchymal Transition in Breast Cancer Cells

Experimental evidence implicates reactive oxygen species (ROS) generation in the hypoxic stabilization of hypoxia-inducible factor (HIF)-1α and in the subsequent expression of promoters of tumor invasiveness and metastatic spread. However, the role played by mitochondrial ROS in hypoxia-induced Epithelial-Mesenchymal Transition (EMT) activation is still unclear. This study was aimed at testing the hypothesis that the inhibition of hypoxia-induced mitochondrial ROS production, mainly at the mitochondrial Complex III UQCRB site, could result in the reversion of EMT, in addition to decreased HIF-1α stabilization. The role of hypoxia-induced ROS increase in HIF-1α stabilization and the ability of antioxidants, some of which directly targeting mitochondrial Complex III, to block ROS production and HIF-1α stabilization and prevent changes in EMT markers were assessed by evaluating ROS, HIF-1α and EMT markers on breast cancer cells, following 48 h treatment with the antioxidants. The specific role of UQCRB in hypoxia-induced EMT was also evaluated by silencing its expression through RNA interference and by assessing the effects of its downregulation on ROS production, HIF-1α levels, and EMT markers. Our results confirm the pivotal role of UQCRB in hypoxic signaling inducing EMT. Thus, UQCRB might be a new therapeutic target for the development of drugs able to reverse EMT by blocking mitochondrial ROS production.

Mitochondria-actin cytoskeleton crosstalk in cell migration

Mitochondria perform diverse functions in the cell and their roles during processes such as cell survival, differentiation, and migration are increasingly being appreciated. Mitochondrial and actin cytoskeletal networks not only interact with each other, but this multifaceted interaction shapes their functional dynamics. The interrelation between mitochondria and the actin cytoskeleton extends far beyond the requirement of mitochondrial ATP generation to power actin dynamics, and impinges upon several major aspects of cellular physiology. Being situated at the hub of cell signaling pathways, mitochondrial function can alter the activity of actin regulatory proteins and therefore modulate the processes downstream of actin dynamics such as cellular migration. As we will discuss, this regulation is highly nuanced and operates at multiple levels allowing mitochondria to occupy a strategic position in the regulation of migration, as well as pathological events that rely on aberrant cell motility such as cancer metastasis. In this review, we summarize the crosstalk that exists between mitochondria and actin regulatory proteins, and further emphasize on how this interaction holds importance in cell migration in normal as well as dysregulated scenarios as in cancer.

The Impacts of Bone Marrow Mesenchymal Stem Cells (BMSCs)-Derived Periostin on Epithelial-Mesenchymal Transition (EMT) of Cervical Cancer Cells

Epithelial-mesenchymal transition (EMT) is closely related to the migrating and invading behaviors of cells. Periostin is one of the essential components in the extracellular matrix and can induce EMT of cells and their sequential metastasis. But its underlying mechanism is unclear. The Hela and BMSC cell lines were assigned into Periostin-mimic group, Periostin-Inhibitor group and Periostin-NC group followed by analysis of cell migration and invasion, expression of E-Cadherin, Vimentin, β-Catenin, Snail, MMP-2, MMP-9, PTEN, and p-PTEN. Cells in Periostin-mimic group exhibited lowest migration, least number of invaded cells, as well as lowest levels of Vimentin, β-Catenin, Snail, MMP-2, MMP-9, p-PTEN, Akt, p-Akt, p-GSK-3β, p-PDK1 and p-cRcf, along with highest levels of E-cadherin and PTEN. Moreover, cells in Periostin-NC group had intermediate levels of these above indicators, while, the Periostin-Inhibitor group exhibited the highest migration rate, the most number of invaded cells, and the highest levels of these proteins (P < 0.05). In conclusion, BMSCs-derived Periostin can influence the EMT of cervical cancer cells possibly through restraining the activity of the PI3K/AKT signal transduction pathway, indicating that Periostin might be a target of chemotherapy in clinics for the treatment of cervical cancer.

Mitochondria-targeted triphenylphosphonium-based compounds inhibit FcεRI-dependent degranulation of mast cells by preventing mitochondrial dysfunction through Erk1/2

AIMS

FcεRI-dependent activation and degranulation of mast cells (MC) play an important role in allergic diseases. We have previously demonstrated that triphenylphosphonium (TPP)-based antioxidant SkQ1 inhibits mast cell degranulation, but the exact mechanism of this inhibition is still unknown. This study focused on investigating the influence of TPP-based compounds SkQ1 and C₁₂TPP on FcεRI-dependent mitochondrial dysfunction and signaling during MC degranulation.

MAIN METHODS

MC were sensitized by anti-dinitrophenyl IgE and stimulated by BSA-conjugated dinitrophenyl. The degranulation of MC was estimated by β-hexosaminidase release. The effect of TPP-based compounds on FcεRI-dependent signaling was determined by Western blot analysis for adapter molecule LAT, kinases Syk, PI3K, Erk1/2, and p38. Fluorescent microscopy was used to evaluate mitochondrial parameters such as morphology, membrane potential, reactive oxygen species and ATP level.

KEY FINDINGS

Pretreatment with TPP-based compounds significantly decreased FcεRI-dependent degranulation of MC. TPP-based compounds also prevented mitochondrial dysfunction (drop in mitochondrial ATP level and mitochondrial fission), and decreased Erk1/2 kinase phosphorylation. Selective Erk1/2 inhibition by U0126 also reduced β-hexosaminidase release and prevented mitochondrial fragmentation during FcεRI-dependent degranulation of MC.

SIGNIFICANCE

These findings expand the fundamental understanding of the role of mitochondria in the activation of MC. It also contributes to the rationale for the development of mitochondrial-targeted drugs for the treatment of allergic diseases.

The Role Played by Mitochondria in FcεRI-Dependent Mast Cell Activation

Mast cells play a key role in the regulation of innate and adaptive immunity and are involved in pathogenesis of many inflammatory and allergic diseases. The most studied mechanism of mast cell activation is mediated by the interaction of antigens with immunoglobulin E (IgE) and a subsequent binding with the high-affinity receptor Fc epsilon RI (FcεRI). Increasing evidences indicated that mitochondria are actively involved in the FcεRI-dependent activation of this type of cells. Here, we discuss changes in energy metabolism and mitochondrial dynamics during IgE-antigen stimulation of mast cells. We reviewed the recent data with regards to the role played by mitochondrial membrane potential, mitochondrial calcium ions (Ca2+) influx and reactive oxygen species (ROS) in mast cell FcεRI-dependent activation. Additionally, in the present review we have discussed the crucial role played by the pyruvate dehydrogenase (PDH) complex, transcription factors signal transducer and activator of transcription 3 (STAT3) and microphthalmia-associated transcription factor (MITF) in the development and function of mast cells. These two transcription factors besides their nuclear localization were also found to translocate in to the mitochondria and functions as direct modulators of mitochondrial activity. Studying the role played by mast cell mitochondria following their activation is essential for expanding our basic knowledge about mast cell physiological functions and would help to design mitochondria-targeted anti-allergic and anti-inflammatory drugs.

Mitochondria-targeted 1,4-naphthoquinone (SkQN) is a powerful prooxidant and cytotoxic agent

An increase in the production of reactive oxygen species (ROS) in mitochondria due to targeted delivery of redox active compounds may be useful in studies of modulation of cell functions by mitochondrial ROS. Recently, the mitochondria-targeted derivative of menadione (MitoK₃) was synthesized. However, MitoK₃ did not induce mitochondrial ROS production and lipid peroxidation while exerting significant cytotoxic action. Here we synthesized 1,4-naphthoquinone conjugated with alkyltriphenylphosphonium (SkQN) as a prototype of mitochondria-targeted prooxidant, and its redox properties, interactions with isolated mitochondria, yeast cells and various human cell lines were investigated. According to electrochemical measurements, SkQN was more active redox agent and, due to the absence of methyl group in the naphthoquinone ring, more reactive as electrophile than MitoK₃. SkQN (but not MitoK₃) stimulated hydrogen peroxide production in isolated mitochondria. At low concentrations, SkQN stimulated state 4 respiration in mitochondria, decreased membrane potential, and blocked ATP synthesis, being more efficient uncoupler of oxidative phosphorylation than MitoK₃. In yeast cells, SkQN decreased cell viability and induced oxidative stress and mitochondrial fragmentation. SkQN killed various tumor cells much more efficiently than MitoK₃. Since many tumors are characterized by increased oxidative stress, the use of new mitochondria-targeted prooxidants may be a promising strategy for anticancer therapy.

Diesel particulate matter2.5 promotes epithelial-mesenchymal transition of human retinal pigment epithelial cells via generation of reactive oxygen species

Although several studies have linked PM_2.5 (particulate matter with a diameter less than 2.5 μm) to ocular surface diseases such as keratitis and conjunctivitis, very few studies have previously addressed its effect on the retina. Therefore, the aim of this study was to evaluate the effect of PM_2.5 on epithelial-mesenchymal transition (EMT), a process involved in disorders of the retinal pigment epithelial (RPE) on APRE-19 cells. PM_2.5 changed the phenotype of RPE cells from epithelial to fibroblast-like mesenchymal, and increased cell migration. Exposure to PM_2.5 markedly increased the expression of mesenchymal markers, but reduced the levels of epithelial markers. Moreover, PM_2.5 promoted the phosphorylation of MAPKs and the expression of transforming growth factor-β (TGF-β)-mediated nuclear transcriptional factors. However, these PM_2.5-mediated changes were completely reversed by LY2109761, a small molecule inhibitor of the TGF-β receptor type I/II kinases, and N-acetyl-L-cysteine (NAC), a reactive oxygen species (ROS) scavenger. Interestingly, NAC, but not LY2109761, effectively restored the PM_2.5-induced mitochondrial defects, including increased ROS, decreased mitochondrial activity, and mitochondrial membrane potential disruption. Collectively, our findings indicate that the TGF-β/Smad/ERK/p38 MAPK signaling pathway is activated downstream of cellular ROS during PM_2.5-induced EMT. The present study provides the first evidence that EMT of RPE may be one of the mechanisms of PM_2.5-induced retinal dysfunction.

Mitochondrial Involvement in Migration, Invasion and Metastasis

Mitochondria in addition to be a main cellular power station, are involved in the regulation of many physiological processes, such as generation of reactive oxygen species, metabolite production and the maintenance of the intracellular Ca²⁺ homeostasis. Almost 100 years ago Otto Warburg presented evidence for the role of mitochondria in the development of cancer. During the past 20 years mitochondrial involvement in programmed cell death regulation has been clarified. Moreover, it has been shown that mitochondria may act as a switchboard between various cell death modalities. Recently, accumulated data have pointed to the role of mitochondria in the metastatic dissemination of cancer cells. Here we summarize the modern knowledge concerning the contribution of mitochondria to the invasion and dissemination of tumor cells and the possible mechanisms behind that and attempts to target metastatic cancers involving mitochondria.

The Regulation of NFE2L2 (NRF2) Signalling and Epithelial-to-Mesenchymal Transition in Age-Related Macular Degeneration Pathology

Age-related macular degeneration (AMD) is a mounting cause of loss of sight in the elderly in the developed countries, a trend enhanced by the continual ageing of the population. AMD is a multifactorial and only partly understood, malady. Unfortunately, there is no effective treatment for most AMD patients. It is known that oxidative stress (OS) damages the retinal pigment epithelium (RPE) and contributes to the progression of AMD. We review here the potential importance of two OS-related cellular systems in relation to AMD. First, the nuclear factor erythroid 2-related factor 2 (NFE2L2; NRF2)-mediated OS response signalling pathway is important in the prevention of oxidative damage and a failure of this system could be critical in the development of AMD. Second, epithelial-to-mesenchymal transition (EMT) represents a change in the cellular phenotype, which ultimately leads to the fibrosis encountered in RPE, a characteristic of AMD. Many of the pathways triggering EMT are promoted by OS. The possible interconnections between these two signalling routes are discussed here. From a broader perspective, the control of NFE2L2 and EMT as ways of preventing OS-derived cellular damage could be potentially valuable in the therapy of AMD.

Oxidative stress induced by carboplatin promotes apoptosis and inhibits migration of HN-3 cells

Laryngeal squamous cell carcinoma (LSCC) is currently a serious public health problem in China; thus, it is urgent to identify effective treatment strategies for this disease. Previous studies demonstrated that reactive oxygen species (ROS) serve important roles in the apoptosis of LSCC cells. It has also been indicated that carboplatin (CBDCA), a second-generation platinum compound with broad antineoplastic properties, is able to induce oxidative stress to produce ROS, which in turn promotes apoptosis. Thus, the present study investigated if CBDCA is cytotoxic in LSCC cells due to the oxidative stress caused by ROS. Therefore, an MTT assay was performed to determine the cell viability of HN-3 LSCC cells following treatment with different doses of CBDCA. Subsequently, the expression levels of ROS and the rate of apoptosis/necrosis were evaluated in the cells. Following this, the HN-3 cells were co-treated with CBDCA and glutathione (GSH) or H₂O2, followed by an MTT assay, a cell migration assay and western blot analysis. The results demonstrated that CBDCA reduced the viability of HN-3 cells in a time- and dose-dependent manner and promoted the production of ROS and apoptosis at certain doses. Additionally, the combination treatment of CBDCA and H2O2 enhanced the inhibitory effects of CBDCA on cell viability and migration ability, and promoted apoptosis in HN-3 cells; whereas the combined treatment of CBDCA and GSH exerted opposite effects. The results of the present study demonstrated that CBDCA promotes the apoptosis of HN-3 cells through accumulation of ROS, which may provide a novel treatment strategy for treating LSCC.

Mitochondria-targeted antioxidant SkQ1 suppresses fibrosarcoma and rhabdomyosarcoma tumour cell growth

Mitochondria are important regulators of tumour growth and progression due to their specific role in cancer metabolism and modulation of apoptotic pathways. In this paper we describe that mitochondria-targeted antioxidant SkQ1 designed as a conjugate of decyl-triphenylphosphonium cation (TPP⁺) with plastoquinone, suppressed the growth of fibrosarcoma HT1080 and rhabdomyosarcoma RD tumour cells in culture and tumour growth of RD in xenograft nude mouse model. Under the same conditions, no detrimental effect of SkQ1 on cell growth of primary human subcutaneous fibroblasts was observed. The tumour growth suppression was shown to be a result of the antioxidant action of low nanomolar concentrations of SkQ1. We have revealed significant prolongation of mitosis induced by SkQ1 in both tumour cell cultures. Prolonged mitosis and apoptosis could be responsible for growth suppression after SkQ1 treatment in RD cells. Growth suppression in HT1080 cells was accompanied by the delay of telophase and cytokinesis, followed by multinuclear cells formation. The effects of SkQ1 on the cell cycle were proved to be at least partially mediated by inactivation of Aurora family kinases.

ABBREVIATIONS

TPP⁺: Triphenylphosphonium cation; ROS: Reactive oxygen species; mtROS: Mitochondrial reactive oxygen species; NAC: N-acetyl-L-cysteine; DCFH-DA: Dichlorodihydrofluorescein diacetate; APC: Anaphase promoting complex; ABPs: Actin-binding proteins; DMEM: Dulbecco's modified Eagle media; SDS: sodium dodecyl sulfate; HEPES: 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid.

Cervical cancer stem-like cells: systematic review and identification of reference genes for gene expression

Cervical cancer is the fourth most common cancer affecting women worldwide. Among many factors, the presence of cancer stem cells, a subpopulation of cells inside the tumor, has been associated with a worse prognosis. Considering the importance of gene expression studies to understand the biology of cervical cancer stem cells (CCSC), this work identifies stable reference genes for cervical cancer cell lines SiHa, HeLa, and ME180 as well as their respective cancer stem-like cells. A literature review was performed to identify validated reference genes currently used to normalize RT-qPCR data in cervical cancer cell lines. Then, cell lines were cultured in regular monolayer or in a condition that favors tumor sphere formation. RT-qPCR was performed using five reference genes: ACTB, B2M, GAPDH, HPRT1, and TBP. Stability was assessed to validate the selected genes as suitable reference genes. The evaluation validated B2M, GAPDH, HPRT1, and TBP in these experimental conditions. Among them, GAPDH and TBP presented the lowest variability according to the analysis by Normfinder, Bestkeeper, and ΔCq methods, being therefore the most adequate genes to normalize the combination of all samples. These results suggest that B2M, GAPDH, HPRT1, and TBP are suitable reference genes to normalize RT-qPCR data of established cervical cancer cell lines SiHa, HeLa, and ME180 as well as their derived cancer stem-like cells. Indeed, GAPDH and TBP seem to be the most convenient choices for studying gene expression in these cells in monolayers or spheres.

Mitochondrial Effects of Teucrium Polium and Prosopis Farcta Extracts in Colorectal Cancer Cells

Background:

Teucrium Polium and Prosopis Farcta have been traditionally employed in cancer treatment. In this study we evaluated the effects of methanolic extracts of these two plants in HT-29 cells.

Methods:

IC50s of extracts were obtained via MTT assay and the levels of ROS production, cell death, collapse of mitochondrial membrane potential and Sirt3 enzyme activity were determined.

Results:

After 48 hours exposure, IC50s for Teucrium and Prosopis extracts were 3 and 2µg/ml, respectively. Extracts induced higher ROS production after 6 hours than after 12 hours. Mitochondrial membrane potential collapse and cell death rate were also increased; Teucrium caused greater cell death than Prosopis. Extracts from both plants increased Sirt3 activity in its normal form, but only Teucrium extract caused a significant increase in activity of Sirt3 enzyme isolated from cancer cells.

Conclusion:

Teucrium and Prosopis extracts exert anticancer activity via mitochondrial alterations, as exemplified by increased ROS levels, Sirt3 activity and cell death in HT-29 colorectal cancer cells.

EMT and inflammation: inseparable actors of cancer progression

Tumors can be depicted as wounds that never heal, and are infiltrated by a large array of inflammatory and immune cells. Tumor-associated chronic inflammation is a hallmark of cancer that fosters progression to a metastatic stage, as has been extensively reviewed lately. Indeed, inflammatory cells persisting in the tumor establish a cross-talk with tumor cells that may result in a phenotype switch into tumor-supporting cells. This has been particularly well described for macrophages and is referred to as tumor-associated 'M2' polarization. Epithelial-to-mesenchymal transition (EMT), the embryonic program that loosens cell-cell adherence complexes and endows cells with enhanced migratory and invasive properties, can be co-opted by cancer cells during metastatic progression. Cancer cells that have undergone EMT are more aggressive, displaying increased invasiveness, stem-like features, and resistance to apoptosis. EMT programs can also stimulate the production of proinflammatory factors by cancer cells. Conversely, inflammation is a potent inducer of EMT in tumors. Therefore, the two phenomena may sustain each other, in an alliance for metastasis. This is the focus of this review, where the interconnections between EMT programs and cellular and molecular actors of inflammation are described. We also recapitulate data linking the EMT/inflammation axis to metastasis.

CD38 enhances the proliferation and inhibits the apoptosis of cervical cancer cells by affecting the mitochondria functions

Cervical cancer is one of the most common malignant tumors in women all over the world. The exact mechanism of occurrence and development of cervical cancer has not been fully elucidated. CD38 is a type II transmembrane glycoprotein, which was found to mediate diverse activities, including signal transduction, cell adhesion, and cyclic ADP-ribose synthesis. Here, we reported that CD38 promoted cell proliferation and inhibited cell apoptosis in cervical cancer cells by affecting the mitochondria functions. We established stable cervical cancer cell lines with CD38 over-expressed. CCK8 assay and colony formation assay indicated that CD38 promoted cervical cancer cell proliferation. Nude mouse tumorigenicity assay showed that CD38 significantly promotes tumor growth in vivo. CD38 also induced S phase accumulation in cell cycle analysis and suppressed cell apoptosis in cervical cancer cells. Meanwhile, flow cytometry analysis of mitochondria functions suggested that CD38 decreased intracellular Ca²⁺ levels in cervical cancer cells and CD38 was involved in down-regulation of ROS levels and prevented mitochondrial apoptosis in cervical cancer cells. The percentage of cells with loss of mitochondrial membrane potential (Δψm) in CD38-overexpressed cervical cancer cells was less than control groups. Furthermore, we found an up-regulation of MDM2, cyclinA1, CDK4, cyclinD1, NF-kB P65, c-rel, and a downregulation of P53, P21, and P38 by Western blot analysis. These results indicated that CD38 enhanced the proliferation and inhibited the apoptosis of cervical cancer cells by affecting the mitochondria functions.