Melatonin enhances TNF-α-mediated cervical cancer HeLa cells death via suppressing CaMKII/Parkin/mitophagy axis

Deficiency of aldehyde dehydrogenase 2 aggravates ethanol-induced cytotoxicity in N2a cells via CaMKII/Drp1-mediated mitophagy

Chronic alcohol abuse causes brain damage and has been associated with an increased risk of Alzheimer's disease. The toxic metabolite of alcohol, acetaldehyde, which is converted to acetate by aldehyde dehydrogenase 2 (ALDH2), has been shown to induce excessive mitochondrial fragmentation and dysfunction leading to neurotoxicity. However, it is still unclear how alcohol affects mitochondrial function in ALDH2-deficient cells. The present study investigated the association between abnormal mitochondrial dynamics, mitophagy and cytotoxicity in ALDH2-deficient N2a cells treated with ethanol. It was found that ethanol induced dynamin-related protein 1 (Drp1)-mediated mitochondrial fragmentation and impaired mitochondrial function, causing excessive mitophagy and cytotoxicity in ALDH2-deficient N2a cells while inducing Ca2+ influx and activating Ca2+/calmodulin-dependent protein kinase II (CaMKII). Inhibition of Ca2+ overload or CaMKII activation prevented Drp1 phosphorylation and ameliorated ethanol-induced mitophagy and cytotoxicity, indicating that Ca2+-dependent CaMKII activation was critical for mediating Drp1-dependent excessive mitochondrial fission and mitophagy in ALDH2-deficient N2a cells. The results of the present study suggested that prevention of intracellular Ca2+ overload might be beneficial for preventing neurotoxicity associated with alcohol abuse in individuals with defective ALDH2.

Chemical mitophagy modulators: Drug development strategies and novel regulatory mechanisms

Maintaining mitochondrial homeostasis is a potential therapeutic strategy for various diseases, including neurodegenerative diseases, cardiovascular diseases, metabolic disorders, and cancer. Selective degradation of mitochondria by autophagy (mitophagy) is a fundamental mitochondrial quality control mechanism conserved from yeast to humans. Indeed, small-molecule modulators of mitophagy are valuable pharmaceutical tools that can be used to dissect complex biological processes and turn them into potential drugs. In the past few years, pharmacological regulation of mitophagy has shown promising therapeutic efficacy in various disease models. However, with the increasing number of chemical mitophagy modulator studies, frequent methodological flaws can be observed, leading some studies to draw unreliable or misleading conclusions. This review attempts (a) to summarize the molecular mechanisms of mitophagy; (b) to propose a Mitophagy Modulator Characterization System (MMCS); (c) to perform a comprehensive analysis of methods used to characterize mitophagy modulators, covering publications over the past 20 years; (d) to provide novel targets for pharmacological intervention of mitophagy. We believe this review will provide a panorama of current research on chemical mitophagy modulators and promote the development of safe and robust mitophagy modulators with therapeutic potential by introducing high methodological standards.

Single-nucleus RNA sequencing and deep tissue proteomics reveal distinct tumour microenvironment in stage-I and II cervical cancer

BACKGROUND

Cervical cancer (CC) is the 3rd most common cancer in women and the 4th leading cause of deaths in gynaecological malignancies, yet the exact progression of CC is inconclusive, mainly due to the high complexity of the changing tumour microenvironment (TME) at different stages of tumorigenesis. Importantly, a detailed comparative single-nucleus transcriptomic analysis of tumour microenvironment (TME) of CC patients at different stages is lacking.

METHODS

In this study, a total of 42,928 and 29,200 nuclei isolated from the tumour tissues of stage-I and II CC patients and subjected to single-nucleus RNA sequencing (snRNA-seq) analysis. The cell heterogeneity and functions were comparatively investigated using bioinformatic tools. In addition, label-free quantitative mass spectrometry based proteomic analysis was carried out. The proteome profiles of stage-I and II CC patients were compared, and an integrative analysis with the snRNA-seq was performed.

RESULTS

Compared with the stage-I CC (CCI) patients, the immune response relevant signalling pathways were largely suppressed in various immune cells of the stage-II CC (CCII) patients, yet the signalling associated with cell and tissue development was enriched, as well as metabolism for energy production suggested by the upregulation of genes associated with mitochondria. This was consistent with the quantitative proteomic analysis that showed the dominance of proteins promoting cell growth and intercellular matrix development in the TME of CCII group. The interferon-α and γ responses appeared the most activated pathways in many cell populations of the CCI patients. Several collagens, such as COL12A1, COL5A1, COL4A1 and COL4A2, were found significantly upregulated in the CCII group, suggesting their roles in diagnosing CC progression. A novel transcript AC244205.1 was detected as the most upregulated gene in CCII patients, and its possible mechanistic role in CC may be investigated further.

CONCLUSIONS

Our study provides important resources for decoding the progression of CC and set the foundation for developing novel approaches for diagnosing CC and tackling the immunosuppressive TME.

Melatonin inhibits endometriosis development by disrupting mitochondrial function and regulating tiRNAs

Endometriosis is a benign gynecological disease characterized by abnormal growth of endometrial-like cells outside the uterus. Melatonin, a hormone secreted by the pineal gland, has been shown to have therapeutic effects in various diseases, including endometriosis. However, the underlying molecular mechanisms are yet to be elucidated. The results of this study demonstrated that melatonin and dienogest administration effectively reduced surgically induced endometriotic lesions in a mouse model. Melatonin suppressed proliferation, induced apoptosis, and dysregulated calcium homeostasis in endometriotic cells and primary endometriotic stromal cells. Melatonin also caused mitochondrial dysfunction by permeating through the mitochondrial membrane to disrupt redox homeostasis in the endometriotic epithelial and stromal cells. Furthermore, melatonin affected oxidative phosphorylation systems to decrease ATP production in End1/E6E7 and VK2/E6E7 cells. This was achieved through messenger RNA-mediated downregulation of respiratory complex subunits. Melatonin inhibited the PI3K/AKT and ERK1/2 pathways and the mitochondria-associated membrane axis and further suppressed the migration of endometriotic epithelial and stromal cells. Furthermore, we demonstrated that tiRNA^GluCTC and tiRNA^AspGTC were associated with the proliferation of endometriosis and that melatonin suppressed the expression of these tiRNAs in primary endometriotic stromal cells and lesions in a mouse model. Thus, melatonin can be used as a novel therapeutic agent to manage endometriosis.

Determination of functional similarity of biosimilar H9P2S from an investigational CHO clone with Adalimumab

Biosimilars, which are replicas of innovator pharmaceuticals, constitute the most significant share of biopharmaceutical products. These products are associated with structural and manufacturing complexities and are hence considered as similar to innovator drugs. Adalimumab is a monoclonal antibody that has been approved by the US FDA for blocking TNF-α. Adalimumab, also known as Humira, is preferred over other anti-TNF-α mAbs because of its lower immunogenicity and enhanced clinical efficacy. As cost-effective mAb development is still a challenging area, we developed an in-house stable CHO-K1 cell line for the production of recombinant monoclonal mAb against TNF-α. This clone yielded H9P2S, as a biosimilar against TNF-α, for which several functional assays were conducted to prove its biosimilarity to Adalimumab. Two batches of H9P2S and their subsequent dilutions were compared with Adalimumab. H9P2S and Adalimumab showed highly similar TNF-α binding and neutralizing activities, confirming the suitability of our clone for yielding biosimilar drugs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03384-z.

Asthma can Promote Cardiomyocyte Mitophagy in a Rat Model

Clinical observations have shown the risk of cardiovascular disease during asthmatic changes. Whether and how asthma causes heart failure is the subject of debate. Here, we aimed to investigate the possibility of cardiomyocyte mitophagy in a rat model of asthma. Twelve mature Wistar rats were randomly allocated into the Control and Asthmatic rats (n = 6). To induce asthma, ovalbumin was injected intraperitoneally on days 1 and 8 and procedure followed by nebulization from days 14 to 32. After 2 weeks, we performed the pathological examination of both lungs and heart using Hematoxylin-Eosin staining. Real-time PCR analysis was used to measure the expression of mitophagic factors, such as Optineurin, Pink1, and mitofusin 1 and 2. Typical changes like increased inter-alveolar septa thickness and interstitial pneumonia were evident in asthmatic lungs. In cardiac tissue, slight inflammatory response, and hydropic degeneration with an eosinophilic appearance were detected in the cytoplasm of cardiomyocytes. Real-time PCR analysis showed mitophagic response in pulmonary and cardiac tissues via upregulation of mitophagy-related genes like Optineurin and Pink-1 in asthmatic lungs and hearts compared to the control group (p < 0.05). Likewise, asthmatic changes increased the expression of genes associated with mitochondrial fusion in the lungs and heart. The expression of mitofusin1 and 2 was significantly increased following inflammatory response in pulmonary and cardiac tissues (p < 0.05). Our findings showed the expression of certain factors related to mitophagy during chronic asthmatic conditions. The findings open a new avenue in the understanding of cardiomyocyte injury during asthma.

Modulation of the immune system by melatonin; implications for cancer therapy

Immune system interactions within the tumour have a key role in the resistance or sensitization of cancer cells to anti-cancer agents. On the other hand, activation of the immune system in normal tissues following chemotherapy or radiotherapy is associated with acute and late effects such as inflammation and fibrosis. Some immune responses can reduce the efficiency of anti-cancer therapy and also promote normal tissue toxicity. Modulation of immune responses can boost the efficiency of anti-tumour therapy and alleviate normal tissue toxicity. Melatonin is a natural body agent that has shown promising results for modulating tumour response to therapy and also alleviating normal tissue toxicity. This review tries to focus on the immunomodulatory actions of melatonin in both tumour and normal tissues. We will explain how anti-cancer drugs may cause toxicity for normal tissues and how tumours can adapt themselves to ionizing radiation and anti-cancer drugs. Then, cellular and molecular mechanisms of immunoregulatory effects of melatonin alone or combined with other anti-cancer agents will be discussed.

Comprehensive Molecular Analyses of a TNF Family-Based Gene Signature as a Potentially Novel Prognostic Biomarker for Cervical Cancer

Background

Increasing evidence suggests that tumour necrosis factor (TNF) family genes play important roles in cervical cancer (CC). However, whether TNF family genes can be used as prognostic biomarkers of CC and the molecular mechanisms of TNF family genes remain unclear.

Methods

A total of 306 CC and 13 normal samples were obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. We identified differentially expressed TNF family genes between CC and normal samples and subjected them to univariate Cox regression analysis for selecting prognostic TNF family genes. Least absolute shrinkage and selection operator (LASSO) regression and multivariate Cox regression analyses were performed to screen genes to establish a TNF family gene signature. Gene set enrichment analysis (GSEA) was performed to investigate the biological functions of the TNF family gene signature. Finally, methylation and copy number variation data of CC were used to analyse the potential molecular mechanisms of TNF family genes.

Results

A total of 26 differentially expressed TNF family genes were identified between the CC and normal samples. Next, a TNF family gene signature, including CD27, EDA, TNF, TNFRSF12A, TNFRSF13C, and TNFRSF9 was constructed based on univariate Cox, LASSO, and multivariate Cox regression analyses. The TNF family gene signature was related to age, pathological stages M and N, and could predict patient survival independently of clinical factors. Moreover, KEGG enrichment analysis suggested that the TNF family gene signature was mainly involved in the TGF-β signaling pathway, and the TNF family gene signature could affect the immunotherapy response. Finally, we confirmed that the mRNA expressions of CD27, TNF, TNFRSF12A, TNFRSF13C, and TNFRSF9 were upregulated in CC, while that of EDA was downregulated. The mRNA expressions of CD27, EDA, TNF, TNFRSF12A, TNFRSF13C, and TNFRSF9 might be influenced by gene methylation and copy number variation.

Conclusion

Our study is the first to demonstrate that CD27, EDA, TNF, TNFRSF12A, TNFRSF13C, and TNFRSF9 might be used as prognostic biomarkers of CC and are associated with the immunotherapy response of CC.

Modulation of the tumor microenvironment (TME) by melatonin

The tumor microenvironment (TME) includes a number of non-cancerous cells that affect cancer cell survival. Although CD8+ T lymphocytes and natural killer (NK) cells suppress tumor growth through induction of cell death in cancer cells, there are various immunosuppressive cells such as regulatory T cells (Tregs), tumor-associated macrophages (TAMs), cancer-associated fibroblasts (CAFs), myeloid-derived suppressor cells (MDSCs), etc., which drive cancer cell proliferation. These cells may also support tumor growth and metastasis by stimulating angiogenesis, epithelial-mesenchymal transition (EMT), and resistance to apoptosis. Interactions between cancer cells and other cells, as well as molecules released into EMT, play a key role in tumor growth and suppression of antitumoral immunity. Melatonin is a natural hormone that may be found in certain foods and is also available as a drug. Melatonin has been demonstrated to modulate cell activity and the release of cytokines and growth factors in TME. The purpose of this review is to explain the cellular and molecular mechanisms of cancer cell resistance as a result of interactions with TME. Next, we explain how melatonin affects cells and interactions within the TME.

Anti-Inflammatory Activity of Melatonin: a Focus on the Role of NLRP3 Inflammasome

Melatonin is a hormone of the pineal gland that contributes to the regulation of physiological activities, such as sleep, circadian rhythm, and neuroendocrine processes. Melatonin is found in several plants and has pharmacological activities including antioxidant, anti-inflammatory, hepatoprotective, cardioprotective, and neuroprotective. It also has shown therapeutic efficacy in treatment of cancer and diabetes. Melatonin affects several molecular pathways to exert its protective effects. The NLRP3 inflammasome is considered a novel target of melatonin. This inflammasome contributes to enhanced level of IL-1β, caspase-1 activation, and pyroptosis stimulation. The function of NLRP3 inflammasome has been explored in various diseases, including cancer, diabetes, and neurological disorders. By inhibiting NLRP3, melatonin diminishes inflammation and influences various molecular pathways, such as SIRT1, microRNA, long non-coding RNA, and Wnt/β-catenin. Here, we discuss these molecular pathways and suggest that melatonin-induced inhibition of NLRP3 should be advanced in disease therapy.

Nujiangexanthone A Inhibits Cervical Cancer Cell Proliferation by Promoting Mitophagy

Nujiangexanthone A (NJXA), a bioactive component isolated from the leaves of Garcinia nujiangensis, has been reported to exhibit anti-inflammatory, antioxidant, and antitumor effects. Our previous work has shown that NJXA induced G0/1 arrest and apoptosis, thus suppressing cervical cancer cell growth. The present study provides new evidence that NJXA can induce cell death in HeLa cells by promoting mitophagy. We first identified that NJXA triggered GFP-LC3 and YFP-Parkin puncta accumulation, which are biomarkers of mitophagy. Moreover, NJXA degraded the mitochondrial membrane proteins Tom20 and Tim23 and mitochondrial fusion proteins MFN1 and MFN2, downregulated Parkin, and stabilized PINK1. Additionally, we revealed that NJXA induced lysosome degradation and colocalization of mitochondria and autophagosomes, which was attenuated by knocking down ATG7, the key regulator of mitophagy. Furthermore, since mitophagy is induced under starvation conditions, we detected the cytotoxic effect of NJXA in nutrient-deprived HeLa cells and observed better cytotoxicity. Taken together, our work contributes to the further clarification of the mechanism by which NJXA inhibits cervical cancer cell proliferation and provides evidence that NJXA has the potential to develop anticancer drugs.

Arginase II protein regulates Parkin-dependent p32 degradation that contributes to Ca2+-dependent eNOS activation in endothelial cells

Aims

Arginase II (ArgII) plays a key role in the regulation of Ca²⁺ between the cytosol and mitochondria in a p32-dependent manner. p32 contributes to endothelial nitric oxide synthase (eNOS) activation through the Ca²⁺/CaMKII/AMPK/p38MAPK/Akt signalling cascade. Therefore, we investigated a novel function of ArgII in the regulation of p32 stability.

Methods and results

mRNA levels were measured by quantitative reverse transcription-PCR, and protein levels and activation were confirmed by western blot analysis. Ca²⁺ concentrations were measured by FACS analysis and a vascular tension assay was performed. ArgII bound to p32, and ArgII protein knockdown using siArgII facilitated the ubiquitin-dependent proteasomal degradation of p32. β-lactone, a proteasome inhibitor, inhibited the p32 degradation associated with endothelial dysfunction in a Ca²⁺-dependent manner. The amino acids Lys154, Lys 180, and Lys220 of the p32 protein were identified as putative ubiquitination sites. When these sites were mutated, p32 was resistant to degradation in the presence of siArgII, and endothelial function was impaired. Knockdown of Pink/Parkin as an E3-ubiquitin ligase with siRNAs resulted in increased p32, decreased [Ca²⁺]c, and attenuated CaMKII-dependent eNOS activation by siArgII. siArgII-dependent Parkin activation was attenuated by KN93, a CaMKII inhibitor. Knockdown of ArgII mRNA and its gene, but not inhibition of its activity, accelerated the interaction between p32 and Parkin and reduced p32 levels. In aortas of ArgII^−/− mice, p32 levels were reduced by activated Parkin and inhibition of CaMKII attenuated Parkin-dependent p32 lysis. siParkin blunted the phosphorylation of the activated CaMKII/AMPK/p38MAPK/Akt/eNOS signalling cascade. However, ApoE^−/− mice fed a high-cholesterol diet had greater ArgII activity, significantly attenuated phosphorylation of Parkin, and increased p32 levels. Incubation with siArgII augmented p32 ubiquitination through Parkin activation, and induced signalling cascade activation.

Conclusion

The results suggest a novel function for ArgII protein in Parkin-dependent ubiquitination of p32 that is associated with Ca²⁺-mediated eNOS activation in endothelial cells.

Melatonin and its mechanism of action in the female reproductive system and related malignancies

Melatonin (N-acetyl-5-methoxytryptamine), the main product of pineal gland in vertebrates, is well known for its multifunctional role which has great influences on the reproductive system. Recent studies documented that melatonin is a powerful free radical scavenger that affects the reproductive system function and female infertility by MT1 and MT2 receptors. Furthermore, cancer researches indicate the influence of melatonin on the modulation of tumor cell signaling pathways resulting in growth inhibitor of the both in vivo/in vitro models. Cancer adjuvant therapy can also benefit from melatonin through therapeutic impact and decreasing the side effects of radiation and chemotherapy. This article reviews the scientific evidence about the influence of melatonin and its mechanism of action on the fertility potential, physiological alteration, and anticancer efficacy, during experimental and clinical studies.

RIP3 facilitates necroptosis through CaMKII and AIF after intracerebral hemorrhage in mice

BACKGROUND

Necroptosis-induced neuronal damage after intracerebral hemorrhage (ICH) has been documented recently. Previous studies have reported that RIP3 and its complex are recognized as central mediators of necroptosis. In this study, the role of RIP3 in the activation of CaMKII and AIF was investigated.

METHODS

We induced ICH in C57BL/6 mice by injecting collagenase IV into the basal ganglia. ICH mice were pretreated with the mPTP inhibitor CsA and the CAMKII inhibitor Kn-93, RIP3 siRNA or RIP3 rAAV. Brain edema and neurobehavior were evaluated. The expression of RIP3, p-MLKL, AIF, and CaMKII proteins was evaluated by western blotting, immunofluorescence (IF) and immunoprecipitation (IP).

RESULTS

Significant increases in RIP3, p-MLKL, CaMKII and AIF expression were observed in ICH mice, and RIP3-AIF colocalized in the nucleus. Overexpression of RIP3 by rAAV upregulated AIF expression in both the cytoplasm and nucleus, while CaMKII expression was increased in the cytoplasm. The interaction of RIP3-AIF and RIP3-CaMKII was detected after ICH injury. These complexes were inhibited by CsA with Kn-93 or RIP3 siRNA pretreatment, which reduced brain edema and neurological deficits.

CONCLUSIONS

Our findings revealed that ICH induced necroptotic neuronal death through the RIP3-CaMKII complex and the RIP3-AIF signaling pathway. Moreover, blockade of mPTP opening could suppress the pathogenesis of necroptosis.

An updated review of mechanistic potentials of melatonin against cancer: pivotal roles in angiogenesis, apoptosis, autophagy, endoplasmic reticulum stress and oxidative stress

Cancers are serious life-threatening diseases which annually are responsible for millions of deaths across the world. Despite many developments in therapeutic approaches for affected individuals, the rate of morbidity and mortality is high. The survival rate and life quality of cancer patients is still low. In addition, the poor prognosis of patients and side effects of the present treatments underscores that finding novel and effective complementary and alternative therapies is a critical issue. Melatonin is a powerful anticancer agent and its efficiency has been widely documented up to now. Melatonin applies its anticancer abilities through affecting various mechanisms including angiogenesis, apoptosis, autophagy, endoplasmic reticulum stress and oxidative stress. Regarding the implication of mentioned cellular processes in cancer pathogenesis, we aimed to further evaluate the anticancer effects of melatonin via these mechanisms.

Parkin: A targetable linchpin in human malignancies

Parkin, an E3 ubiquitin ligase has been found to be deregulated in a variety of human cancers. Our current understanding is endowed with strong evidences that Parkin plays crucial role in the pathogenesis of cancer by controlling/interfering with major hallmarks of cancer delineated till today. Consistent with the idea of mitophagy, the existing studies imitates the tumor suppressive potential of Parkin, resolved by its capacity to regulate cell proliferation, cell migration, angiogenesis, apoptosis and overall cellular survival. Dysfunction of Parkin has resulted in the loss of ubiquitination of cell cycle components followed by their accumulation leading to genomic instability, perturbed cell cycle and eventually tumor progression. In this review, we provide an overview of current knowledge about the critical role of Parkin in cancer development and progression and have focussed on its therapeutic implications highlighting the diagnostic and prognostic value of Parkin as a biomarker. We earnestly hope that an in-depth knowledge of Parkin will provide a linchpin to target in various cancers that will open a new door of clinical applications and therapeutics.

A Comprehensive Understanding of the Anticancer Mechanisms of FDY2004 Against Cervical Cancer Based on Network Pharmacology

Herbal drugs are continuously being developed and used as effective therapeutics for various cancers, such as cervical cancer (CC); however, their mechanisms of action at a systemic level have not been explored fully. To study such mechanisms, we conducted a network pharmacological investigation of the anti-CC mechanisms of FDY2004, an herbal drug consisting of Moutan Radicis Cortex, Persicae Semen , and Rhei Radix et Rhizoma. We found that FDY2004 inhibited the viability of human CC cells. By performing pharmacokinetic evaluation and network analysis of the phytochemical components of FDY2004, we identified 29 bioactive components and their 116 CC-associated pharmacological targets. Gene ontology enrichment analysis showed that the modulation of cellular functions, such as apoptosis, growth, proliferation, and survival, might be mediated through the FDY2004 targets. The therapeutic targets were also key components of CC-associated oncogenic and tumor-suppressive pathways, including PI3K-Akt, human papillomavirus infection, IL-17, MAPK, TNF, focal adhesion, and viral carcinogenesis pathways. In conclusion, our data present a comprehensive insight for the mechanisms of the anti-CC properties of FDY2004.

Role and Therapeutic Potential of Melatonin in Various Type of Cancers

Cancer is a large group of diseases and the second leading cause of death worldwide. Lung, prostate, colorectal, stomach, and liver cancers are the most common types of cancer in men, whereas breast, colorectal, lung, cervical, and thyroid cancers are the most common among women. Presently, various treatment strategies, including surgical resection combined with chemotherapy, radiotherapy, nanotherapy, and immunotherapy, have been used as conventional treatments for patients with cancer. However, the clinical outcomes of advanced-stage disease remain relatively unfavorable owing to the emergence of chemoresistance, toxicity, and other undesired detrimental side effects. Therefore, new therapies to overcome these limitations are indispensable. Recently, there has been considerable evidence from experimental and clinical studies suggesting that melatonin can be used to prevent and treat cancer. Studies have confirmed that melatonin mitigates the pathogenesis of cancer by directly affecting carcinogenesis and indirectly disrupting the circadian cycle. Melatonin (MLT) is nontoxic and exhibits a range of beneficial effects against cancer via apoptotic, antiangiogenic, antiproliferative, and metastasis-inhibitory pathways. The combination of melatonin with conventional drugs improves the drug sensitivity of cancers, including solid and liquid tumors. In this manuscript, we will comprehensively review some of the cellular, animal, and human studies from the literature that provide evidence that melatonin has oncostatic and anticancer properties. Further, this comprehensive review compiles the available experimental and clinical data analyzing the history, epidemiology, risk factors, therapeutic effect, clinical significance, of melatonin alone or in combination with chemotherapeutic agents or radiotherapy, as well as the underlying molecular mechanisms of its anticancer effect against lung, breast, prostate, colorectal, skin, liver, cervical, and ovarian cancers. Nonetheless, in the interest of readership clarity and ease of reading, we have discussed the overall mechanism of the anticancer activity of melatonin against different types of cancer. We have ended this report with general conclusions and future perspectives.

To betray or to fight? The dual identity of the mitochondria in cancer

Mitochondria are highly dynamic organelles that provide energy for oxidative phosphorylation in cells. Equally, they are the major sites for the metabolism of amino acids, lipids and iron. When cells become cancerous, the morphology, cellular location and metabolic mode of the mitochondria change accordingly. These mitochondrial changes can have two opposing effects on cancer: procancer and anticancer effects. Specifically, mitochondria play roles in the fight against cancer by participating in processes such as ferroptosis, mitophagy and antitumor immunity. Contrastingly, cancer cells can also enslave mitochondria to give them the conditions necessary for growth and metastasis. Moreover, through mitochondria, cancer cells can escape from immune surveillance, resulting in their immune escape and enhanced malignant transformation ability. At present, cancer-related studies of mitochondria are one-sided; therefore, we aim to provide a comprehensive understanding by systematically reviewing the two-sided cancer-related properties of mitochondria. Mitochondrial-targeted drugs are gradually emerging and showing significant advantages in cancer treatment; thus, our in-depth exploration of mitochondria in cancer will help to provide theoretical support for the future provision of efficient and low-toxicity cancer treatments.

The negative charge of the 343 site is essential for maintaining physiological functions of CXCR4

BACKGROUND

Warts, hypogammaglobulinemia, recurrent bacterial infections and myelokathexis (WHIM) syndrome is a primary immunodeficiency disease (PID) usually caused by autosomal dominant mutations in the chemokine receptor CXCR4 gene. To date, a total of nine different mutations including eight truncation mutations and one missense mutation (E343K, CXCR4^E343K) distributed in the C-terminus of CXCR4 have been identified in humans. Studies have clarified that the loss of phosphorylation sites in the C-terminus of truncated CXCR4 impairs the desensitization process, enhances the activation of G-protein, prolongs downstream signaling pathways and introduces over immune responses, thereby causing WHIM syndrome. So far, there is only one reported case of WHIM syndrome with a missense mutation, CXCR4^E343K, which has a full length of C-terminus with entire phosphorylation sites, no change in all potential phosphorylation sites. The mechanism of the missense mutation (CXCR4^E343K) causing WHIM syndrome is unknown. This study aimed to characterize the effect of mutation at the 343 site of CXCR4 causing the replacement of arginine/E with glutamic acid/K on the receptor signal transduction, and elucidate the mechanism underling CXCR4^E343K causing WHIM in the reported family.

RESULTS

We completed a series of mutagenesis to generate different mutations at the 343 site of CXCR4 tail, and established a series of HeLa cell lines stably expressing CXCR4^WT or CXCR4^E343D (glutamic acid/E replaced with aspartic acid/D) or CXCR4^E343K (glutamic acid/E replaced with lysine/K) or CXCR4^E343R (glutamic acid/E replaced with arginine/R) or CXCR4^E343A (glutamic acid/E replaced with alanine/A) and then systematically analyzed functions of the CXCR4 mutants above. Results showed that the cells overexpressing of CXCR4^E343D had no functional changes with comparison that of wild type CXCR4. However, the cells overexpressing of CXCR4^E343K or CXCR4^E343R or CXCR4^E343A had enhanced cell migration, prolonged the phosphorylation of ERK1/2, p38, JNK1/2/3, aggravated activation of PI3K/AKT/NF-κB signal pathway, introduced higher expression of TNFa and IL6, suggesting over immune response occurred in CXCR4 mutants with charge change at the 343 site of receptor tail, as a result, causing WHIM syndrome. Biochemical analysis of those mutations at the 343 site of CXCR4 above shows that CXCR4 mutants with no matter positive or neutral charge have aberrant signal pathways downstream of activated mutated CXCR4, only CXVR4 with negative charge residues at the site shows normal signal pathway post activation with stromal-derived factor (SDF1, also known as CXCL12).

CONCLUSION

Taken together, our results demonstrated that the negative charge at the 343 site of CXCR4 plays an essential role in regulating the down-stream signal transduction of CXCR4 for physiological events, and residue charge changes, no matter positive or neutral introduce aberrant activities and functions of CXCR4, thus consequently lead to WHIM syndrome.

High uric acid promotes mitophagy through the ROS/CaMKIIδ/Parkin pathway in cardiomyocytes in vitro and in vivo

BACKGROUND

Increasing evidence has suggested that high uric acid (HUA) is closely related to cardiovascular disease (CVD). Mitophagy abnormalities have been reported to participate in multiple pathogenic processes of CVD. However, the potential molecular mechanisms remain unclear. Herein, we investigated the effect of HUA-induced mitophagy and its potential molecular mechanism in cardiomyocytes.

METHODS

We established a model of cardiomyocytes induced by HUA in vitro and in vivo. Mitochondrial membrane potential (MMP), reactive oxygen species (ROS) production and adenosine triphosphate (ATP) content were measured. The mitophagy-related protein expression of LC3B-II, Parkin, Ca²⁺/calmodulin-dependent protein kinase II δ (CaMKIIδ) and P62 was measured by Western blot. Based on the colocalization of lysosomes and mitochondria, a confocal microscope was used to detect mitophagy. Additionally, we established a mitophagy inhibitor group (3-MA) and CaMKIIδ inhibitor group (KN-93) to verify the pathway.

RESULTS

In the HUA stimulation model, ROS production was increased, and mitochondrial injury indexes (MMP and ATP contents) were decreased. Moreover, these indicators were reversed by 3-MA and KN-93. Under HUA stimulation, the expression of LC3B-II, Parkin, CaMKIIδ and P62 increased significantly. Furthermore, these protein levels were reduced by 3-MA and KN-93.

CONCLUSION

HUA can promote cardiomyocyte mitophagy activation through the ROS/CaMKIIδ/parkin pathway axis. This study may provide a new target and theoretical basis for the prevention and treatment of HUA-related metabolic heart disease in the future.

CXCL5 contributes to the tumorigenicity of cervical cancer and is post-transcriptionally regulated by miR-577

BACKGROUND

C-X-C motif chemokine ligand 5 (CXCL5), an important chemokine, has been validated to promote human tumorigenesis. However, the clinical significance and the underlying molecular mechanisms of CXCL5 have not been completely explored in cervical cancer. Herein, the aim was to investigate miR-577-mediated CXCL5 signaling in cervical tumorigenicity.

MATERIAL AND METHODS

Sixty-one pairs of cervical cancer specimens and para-carcinoma tissues were collected to measure miR-577 and CXCL5 expression levels. miR-577 mimics and/or si-CXCL5 were transfected into cervical cancer cell lines, Hela, and SiHa cells, to determine their effect on cell proliferation, migration and apoptosis.

RESULTS

Our results demonstrated that CXCL5 is overexpressed in cervical cancer tissues and cell lines. Knockdown of CXCL5 with specific siRNA transfection in Hela and SiHa cells significantly inhibited cell proliferation and migration and induced apoptosis in vitro. We also report that CXCL5 is a direct target of miR-577. Additionally, transfection of miR-577 mimics can inhibit CXCL5 protein expression, but not mRNA in Hela cells. miR-577 mimic transfection significantly inhibits migration and induces apoptosis in Hela and SiHa cells. However, the antineoplastic activities of miR-577 are reversed by overexpression of CXCL5 in vitro.

CONCLUSIONS

Overexpression of CXCL5 is involved in tumor development of cervical cancer. Inhibition of CXCL5 by its post-transcriptional regulator, miR-577, may provide a promising therapeutic strategy for patients with cervical cancer.

Mitophagy Receptors in Tumor Biology

Mitochondria are multifunctional organelles that regulate cancer biology by synthesizing macromolecules, producing energy, and regulating cell death. The understanding of mitochondrial morphology, function, biogenesis, fission and fusion kinetics, and degradation is important for the development of new anticancer strategies. Mitophagy is a type of selective autophagy that can degrade damaged mitochondria under various environmental stresses, especially oxidative damage and hypoxia. The key regulator of mitophagy is the autophagy receptor, which recognizes damaged mitochondria and allows them to enter autophagosomes by binding to MAP1LC3 or GABARAP, and then undergo lysosomal-dependent degradation. Many components of mitochondria, including mitochondrial membrane proteins (e.g., PINK1, BNIP3L, BNIP3, FUNDC1, NIPSNAP1, NIPSNAP2, BCL2L13, PHB2, and FKBP8) and lipids (e.g., cardiolipin and ceramides), act as mitophagy receptors in a context-dependent manner. Dysfunctional mitophagy not only inhibits, but also promotes, tumorigenesis. Similarly, mitophagy plays a dual role in chemotherapy, radiotherapy, and immunotherapy. In this review, we summarize the latest advances in the mechanisms of mitophagy and highlight the pathological role of mitophagy receptors in tumorigenesis and treatment.

Melatonin and regulation of autophagy: Mechanisms and therapeutic implications

Mitochondria are essential subcellular units that generate basic energy for the cell, as well as influence Ca²⁺ flux, apoptosis, and cell signaling. Mitophagy can selectively remove impaired mitochondria to preserve mitochondrial function, which is crucial for normal cellular maintenance. Mitochondrial dysfunction and mitophagy are widely reported to be linked to various pathogeneses. In addition, there is increasing evidence regarding the beneficial role of melatonin in the regulation and intervention of mitophagy progression. In this review, we focus on specific pathological conditions, including ischemia/reperfusion injury (IRI), cancer and neurodegenerative diseases, and elucidate the essential role of melatonin in the modulation of mitophagy in each of these distinct disorders.

Melatonin and gastrointestinal cancers: Current evidence based on underlying signaling pathways

Gastrointestinal (GI) cancers, leading causes of cancer-related deaths, have been serious challenging human diseases up to now. Because of high rates of mortality, late-stage diagnosis, metastasis to distant locations, and low effectiveness and adverse events of routine standard therapies, the quality of life and survival time are low in patients with GI cancers. Hence, many efforts need to be done to explore and find novel efficient treatments. Beneficial effects of melatonin have been reported in a wide variety of human diseases. Melatonin has antioxidant, anti-inflammatory, antimicrobial, and anticancer effects. Various studies have showed the regulatory effects of melatonin on apoptotsis, autophagy and angiogenesis; these properties result in the inhibition of invasion, migration, and proliferation of GI cancer cells in vivo and in vitro. Together, this review suggests that melatonin in combination with anticancer agents may improve the efficacy of routine medicine and survival rate of patients with cancer.

Anticancer and cytotoxic effects of troxerutin on HeLa cell line: an in-vitro model of cervical cancer

Cervical cancer is one of the grave uterine tumors which leads to death in women worldwide. Troxerutin (TRX) as a bioflavonoid compound has many pharmacological effects such as anti-neoplastic, radioprotective, and anti-cancer. The present study was designed to examine the cytotoxic effect of TRX on human HeLa tumor cells. Human HeLa cells were cultured and treated with different doses of TRX (20-640 mg/ml) to evaluate the effective half-maximal inhibitory concentration (IC₅₀) after 24 h. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test was used for cell proliferation assay. Also, the Bax, Bcl-2, cleaved caspase-3, and tumor necrosis factor-α (TNF-α) protein expression levels were detected with immunoblotting analysis. The malondialdehyde (MDA) concentration, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity levels were measured via their commercial kits. Data were analyzed using one-way ANOVA. The result showed that TRX at 320 mg/ml concentration (IC₅₀) has a growth inhibitory effect against HeLa cells at 24 h treatment (P ˂ 0.01). Moreover, it increased the MDA concentration and also decreased the GPx and SOD activity levels at 320 mg/ml concentration versus control (P < 0.001). Also, TRX significantly up-regulated the Bax, cleaved caspase-3 and TNF-α proteins expression levels (P  <  0.01) and down-regulated the Bcl-2 protein expression in HeLa tumor cells at 320 mg/ml concentration compared to control (P < 0.05). Our study showed that 24 h of treatment with TRX (320 mg/ml) has apoptotic and growth inhibitory effects against HeLa cells. It can induce inflammation (at least via up-regulating the TNF-α protein expression) and oxidative stress in human HeLa cells.

Melatonin Attenuates Anoxia/Reoxygenation Injury by Inhibiting Excessive Mitophagy Through the MT2/SIRT3/FoxO3a Signaling Pathway in H9c2 Cells

Purpose

Autophagy caused by ischemia/reperfusion (I/R) increases the extent of cardiomyocyte damage. Melatonin (Mel) diminishes cardiac injury through regulating autophagy and mitochondrial dynamics. However, illustrating the specific role of mitophagy in the cardioprotective effects of melatonin remains a challenge. The aim of our research was to investigate the impact and underlying mechanisms of melatonin in connection with mitophagy during anoxia/reoxygenation (A/R) injury in H9c2 cells.

Methods

H9c2 cells were pretreated with melatonin with or without the melatonin membrane receptor 2 (MT2) antagonist 4-P-PDOT, the MT2 agonist IIK7 and the sirtuin 3 (SIRT3) inhibitor 3-TYP for 4 hours and then subjected to A/R injury. Cell viability, cellular apoptosis, necrosis levels and oxidative markers were assessed. The expression of SIRT3 and forkhead box O3a (FoxO3a), mitochondrial function and the levels of mitophagy-related proteins were also evaluated.

Results

A/R injury provoked enhanced mitophagy in H9c2 myocytes. In addition, increased mitophagy was correlated with decreased cellular viability, increased oxidative stress and mitochondrial dysfunction in H9c2 cells. However, melatonin pretreatment notably increased cell survival and decreased cell apoptosis and oxidative response after A/R injury, accompanied by restored mitochondrial function. The inhibition of excessive mitophagy is involved in the cardioprotective effects of melatonin, as shown by the decreased expression of the mitophagy-related molecules Parkin, Beclin1, and BCL2-interacting protein 3-like (BNIP3L, best known as NIX) and decreased light chain 3 II/light chain 3 I (LC3 II/LC3 I) ratio and upregulation of p62 expression. Moreover, the decreased expression of SIRT3 and FoxO3a in A/R-injured H9c2 cells was abrogated by melatonin, but these beneficial effects were attenuated by the MT2 antagonist 4-P-PDOT or the SIRT3 inhibitor 3-TYP and enhanced by the MT2 agonist IIK7.

Conclusion

These results indicate that melatonin protects H9c2 cells during A/R injury through suppressing excessive mitophagy by activating the MT2/SIRT3/FoxO3a pathway. Melatonin may be a useful candidate for alleviating myocardial ischemia/reperfusion (MI/R) injury in the future, and the MT2 receptor might become a therapeutic target.

RBR E3 ubiquitin ligases in tumorigenesis

RING-in-between-RING (RBR) E3 ligases are one class of E3 ligases that is characterized by the unique RING-HECT hybrid mechanism to function with E2s to transfer ubiquitin to target proteins for degradation. Emerging evidence has demonstrated that RBR E3 ligases play essential roles in neurodegenerative diseases, infection, inflammation and cancer. Accumulated evidence has revealed that RBR E3 ligases exert their biological functions in various types of cancers by modulating the degradation of tumor promoters or suppressors. Hence, we summarize the differential functions of RBR E3 ligases in a variety of human cancers. In general, ARIH1, RNF14, RNF31, RNF144B, RNF216, and RBCK1 exhibit primarily oncogenic roles, whereas ARIH2, PARC and PARK2 mainly have tumor suppressive functions. Moreover, the underlying mechanisms by which different RBR E3 ligases are involved in tumorigenesis and progression are also described. We discuss the further investigation is required to comprehensively understand the critical role of RBR E3 ligases in carcinogenesis. We hope our review can stimulate the researchers to deeper explore the mechanism of RBR E3 ligases-mediated carcinogenesis and to develop useful inhibitors of these oncogenic E3 ligases for cancer therapy.

LncRNA HAND2-AS1 represses cervical cancer progression by interaction with transcription factor E2F4 at the promoter of C16orf74

Cervical cancer is one of the major malignancies, the pathophysiology and progression of which remain to be scarcely understood. Long non-coding RNAs (lncRNAs) have been previously implicated in the progression of cervical cancer. Here, the purpose of this study was to identify whether lncRNA heart- and neural crest derivative-expressed 2-antisense RNA 1 (HAND2-AS1) affect the development of cervical cancer through regulation of chromosome 16 open reading frame 74 (C16orf74) by mediating a transcription factor E2F4. RT-qPCR was performed to determine the expression of HAND2-AS1 in cervical cancer cells. Then, cervical cancer cells were treated with HAND2-AS1 or si-E2F4 RNA, or C16orf74, after which the proliferation, colony formation, migration and invasion were detected. Moreover, the binding between HAND2-AS1 and E2F4 or between E2F4 and C16orf74 was explored. Finally, the tumorigenesis of cervical cancer cells was measured in nude mice with altered HAND2-AS1/E2F4/C16orf74 expression. HAND2-AS1 exhibited poor expression in cervical cancer, and HAND2-AS1 overexpression suppressed the proliferation, colony formation, migration and invasion of cervical cancer cells. In addition, HAND2-AS1 was found to recruit transcription factor E2F4 to C16orf74 promoter region and down-regulate C16orf74 expression. Lastly, HAND2-AS1/E2F4/C16orf74 modulated the tumorigenesis of cervical cancer in nude mice. In conclusion, this study provided evidence on the inhibitory effect of HAND2-AS1 on the development of cervical cancer through the suppression of C16orf74 expression by recruiting transcription factor E2F4. This study highlights the potential of lncRNA HAND2-AS1 as a target in the treatment of cervical cancer.

Melatonin modulates red-ox state and decreases viability of rat pancreatic stellate cells

In this work we have studied the effects of pharmacological concentrations of melatonin (1 µM-1 mM) on pancreatic stellate cells (PSC). Cell viability was analyzed by AlamarBlue test. Production of reactive oxygen species (ROS) was monitored following CM-H₂DCFDA and MitoSOX Red-derived fluorescence. Total protein carbonyls and lipid peroxidation were analyzed by HPLC and spectrophotometric methods respectively. Mitochondrial membrane potential (ψ_m) was monitored by TMRM-derived fluorescence. Reduced (GSH) and oxidized (GSSG) levels of glutathione were determined by fluorescence techniques. Quantitative reverse transcription-polymerase chain reaction was employed to detect the expression of Nrf2-regulated antioxidant enzymes. Determination of SOD activity and total antioxidant capacity (TAC) were carried out by colorimetric methods, whereas expression of SOD was analyzed by Western blotting and RT-qPCR. The results show that melatonin decreased PSC viability in a concentration-dependent manner. Melatonin evoked a concentration-dependent increase in ROS production in the mitochondria and in the cytosol. Oxidation of proteins was detected in the presence of melatonin, whereas lipids oxidation was not observed. Depolarization of ψ_m was noted with 1 mM melatonin. A decrease in the GSH/GSSG ratio was observed, that depended on the concentration of melatonin used. A concentration-dependent increase in the expression of the antioxidant enzymes catalytic subunit of glutamate-cysteine ligase, catalase, NAD(P)H-quinone oxidoreductase 1 and heme oxygenase-1 was detected in cells incubated with melatonin. Finally, decreases in the expression and in the activity of superoxide dismutase were observed. We conclude that pharmacological concentrations melatonin modify the redox state of PSC, which might decrease cellular viability.

Mitophagy: A crucial modulator in the pathogenesis of chronic diseases

Mitophagy is an autophagic process through which damaged or dysfunctional mitochondria are specifically degraded to maintain cellular homeostasis. It is highly regulated by various signaling pathways such as the PTEN-induced putative kinase 1 (PINK1)/Parkin and NIP3-like protein X (NIX)/BNIP3 pathways. Additionally, it plays a crucial role in inducing some pathological processes. Notably, some evidence suggesting the association of mitophagy with the occurrence of chronic diseases such as Parkinson's disease (PD), cancer, diabetes, atherosclerosis (AS), and myocardial ischemia reperfusion (MIR) injury is available. Particularly, it has been reported that mitophagy could hinder the development of PD by activating the PINK1/Parkin pathway and acting as a defense mechanism against the induction of diabetes. Conversely, the induction of mitophagy plays dual roles in driving the process of cancer, AS, and MIR injury. In this review, we have explained the role and regulatory mechanisms through which mitophagy plays a role in these chronic pathologies. Importantly, the pharmacological targeting of mitophagy might prove to be a potential alternative for the treatment of these chronic diseases.

Mitochonic acid-5 attenuates TNF-α-mediated neuronal inflammation via activating Parkin-related mitophagy and augmenting the AMPK-Sirt3 pathways

Mitochondrial dysfunction has been found to be associated with neuronal inflammation; however, no effective drug is available to attenuate neuroinflammation via sustaining mitochondrial function. In the current study, experiments were performed to understand the beneficial effects of mitochonic acid 5 (MA-5) on tumor necrosis factor-α (TNF-α)-mediated neuronal injury and mitochondrial damage. Our data illustrated that MA-5 pretreatment reduced inflammation response induced by TNF-α in CATH.a cells. Molecular investigations demonstrated that MA-5 pretreatment repressed oxidative stress, inhibited endoplasmic reticulum stress, sustained cellular energy metabolism, and blocked cell apoptosis induced by TNF-α stress. Further, we found that MA-5 treatment elevated the expression of Sirtuin 3 (Sirt3) and this effect was dependent on the activation of AMP-activated protein kinase (AMPK) pathway. Blockade of AMPK abolished the promotive action of MA-5 on Sirt3 and thus mediated mitochondrial damage and cell death. Besides, we also found that MA-5 treatment augmented Parkin-related mitophagy and increased mitophagy promoted CATH.a cells survival via improving mitochondrial function. Knockdown of Parkin abolished the beneficial action of MA-5 on mitochondrial homeostasis and CATH.a cell survival. Altogether, our results confirm that MA-5 is an effective drug to attenuate neuroinflammation via sustaining mitochondrial damage and promoting CATH.a cell survival. The protective action of MA-5 on neuronal damage is associated with Parkin-related mitophagy and the activation of AMPK-Sirt3 pathways.