Autophagy-disrupted LC3 abundance leads to death of supporting cells of human oocytes

The role of autophagy in brain health and disease: Insights into exosome and autophagy interactions

Effective management of cellular components is essential for maintaining brain health, and studies have identified several crucial biological processes in the brain. Among these, autophagy and the role of exosomes in cellular communication are critical for brain health and disease. The interaction between autophagy and exosomes in the nervous system, as well as their contributions to brain damage, have garnered significant attention. This review summarizes that exosomes and their cargoes have been implicated in the autophagy process in the pathophysiology of nervous system diseases. Furthermore, the onset and progression of neurological disorders may be affected by autophagy regulation of the secretion and release of exosomes. These findings may provide new insights into the potential mechanism by which autophagy mediates different exosome secretion and release, as well as the valuable biomedical applications of exosomes in the prevention and treatment of various brain diseases by targeting autophagy.

RAB37-mediated autophagy guards ovarian homeostasis and function

Loss of ovarian homeostasis is associated with ovary dysfunction and female diseases; however, the underlying mechanisms responsible for the establishment of homeostasis and its function in the ovary have not been fully elucidated. Here, we showed that conditional knockout of Rab37 in oocytes impaired macroautophagy/autophagy proficiency in the ovary and interfered with follicular homeostasis and ovary development in mice. Flunarizine treatment upregulated autophagy, thus rescuing the impairment of follicular homeostasis and ovarian dysfunction in rab37 knockout mice by reprogramming of homeostasis. Notably, both the E2F1 and EGR2 transcription factors synergistically activated Rab37 transcription and promoted autophagy. Thus, RAB37-mediated autophagy ensures ovary function by maintaining ovarian homeostasis.Abbreviations: AMH: anti-Mullerian hormone; ATG: autophagy related; BECN1: beclin 1; cKO: conditional knockout; Cre: cyclization recombination enzyme; dpp: days postpartum; E2: estradiol; E2F1: E2F transcription factor 1; EBF1: EBF transcription factor 1; EGR2: early growth response 2; FSH: follicle stimulating hormone; LH: luteinizing hormone; mpp: months postpartum; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; RAB37: RAB37, member RAS oncogene family; SQSTM1: sequestosome 1; TFEB: transcription factor EB; Zp3: zona pellucida glycoprotein 3.

The constructive and destructive impact of autophagy on both genders' reproducibility, a comprehensive review

Reproduction is characterized by a series of massive renovations at molecular, cellular, and tissue levels. Recent studies have strongly tended to reveal the involvement of basic molecular pathways such as autophagy, a highly conserved eukaryotic cellular recycling, during reproductive processes. This review comprehensively describes the current knowledge, updated to September 2022, of autophagy contribution during reproductive processes in males including spermatogenesis, sperm motility and viability, and male sex hormones and females including germ cells and oocytes viability, ovulation, implantation, fertilization, and female sex hormones. Furthermore, the consequences of disruption in autophagic flux on the reproductive disorders including oligospermia, azoospermia, asthenozoospermia, teratozoospermia, globozoospermia, premature ovarian insufficiency, polycystic ovarian syndrome, endometriosis, and other disorders related to infertility are discussed as well.Abbreviations: AKT/protein kinase B: AKT serine/threonine kinase; AMPK: AMP-activated protein kinase; ATG: autophagy related; E2: estrogen; EDs: endocrine disruptors; ER: endoplasmic reticulum; FSH: follicle stimulating hormone; FOX: forkhead box; GCs: granulosa cells; HIF: hypoxia inducible factor; IVF: in vitro fertilization; IVM: in vitro maturation; LCs: Leydig cells; LDs: lipid droplets; LH: luteinizing hormone; LRWD1: leucine rich repeats and WD repeat domain containing 1; MAP1LC3: microtubule associated protein 1 light chain 3; MAPK: mitogen-activated protein kinase; MTOR: mechanistic target of rapamycin kinase; NFKB/NF-kB: nuclear factor kappa B; P4: progesterone; PCOS: polycystic ovarian syndrome; PDLIM1: PDZ and LIM domain 1; PI3K: phosphoinositide 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; PtdIns3K: class III phosphatidylinositol 3-kinase; POI: premature ovarian insufficiency; ROS: reactive oxygen species; SCs: Sertoli cells; SQSTM1/p62: sequestosome 1; TSGA10: testis specific 10; TST: testosterone; VCP: vasolin containing protein.

Moschus ameliorates glutamate-induced cellular damage by regulating autophagy and apoptosis pathway

Alzheimer's disease (AD), a neurodegenerative disorder, causes short-term memory and cognition declines. It is estimated that one in three elderly people die from AD or other dementias. Chinese herbal medicine as a potential drug for treating AD has gained growing interest from many researchers. Moschus, a rare and valuable traditional Chinese animal medicine, was originally documented in Shennong Ben Cao Jing and recognized for its properties of reviving consciousness/resuscitation. Additionally, Moschus has the efficacy of "regulation of menstruation with blood activation, relief of swelling and pain" and is used for treating unconsciousness, stroke, coma, and cerebrovascular diseases. However, it is uncertain whether Moschus has any protective effect on AD patients. We explored whether Moschus could protect glutamate (Glu)-induced PC12 cells from cellular injury and preliminarily explored their related action mechanisms. The chemical compounds of Moschus were analyzed and identified by GC-MS. The Glu-induced differentiated PC12 cell model was thought to be the common AD cellular model. The study aims to preliminarily investigate the intervention effect of Moschus on Glu-induced PC12 cell damage as well as their related action mechanisms. Cell viability, lactate dehydrogenase (LDH), mitochondrial reactive oxygen species, mitochondrial membrane potential (MMP), cell apoptosis, autophagic vacuoles, autolysosomes or autophagosomes, proteins related to apoptosis, and the proteins related to autophagy were examined and analyzed. Seventeen active compounds of the Moschus sample were identified based on GC-MS analysis. In comparison to the control group, Glu stimulation increased cell viability loss, LDH release, mitochondrial damage, loss of MMP, apoptosis rate, and the number of cells containing autophagic vacuoles, and autolysosomes or autophagosomes, while these results were decreased after the pretreatment with Moschus and 3-methyladenine (3-MA). Furthermore, Glu stimulation significantly increased cleaved caspase-3, Beclin1, and LC3II protein expression, and reduced B-cell lymphoma 2/BAX ratio and p62 protein expression, but these results were reversed after pretreatment of Moschus and 3-MA. Moschus has protective activity in Glu-induced PC12 cell injury, and the potential mechanism might involve the regulation of autophagy and apoptosis. Our study may promote research on Moschus in the field of neurodegenerative diseases, and Moschus may be considered as a potential therapeutic agent for AD.

The Roles of Autophagy in the Genesis and Development of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common and frequent disease and always leads endocrine and metabolic disorder among women in reproductive age. Ovary is the main organ involved in polycystic ovary syndrome, and its function impairment will lead to reproductive dysfunction. Some recent studies have demonstrated that autophagy plays an important role in the pathogenesis of PCOS, and there are many different mechanisms that affect autophagy and the occurrence of PCOS, and they provide a new direction for us to predict the mechanism of PCOS. In this review, we discuss the role of autophagy in different ovarian cells: granulosa cells, oocytes, and theca cells, and introduce the important role that they play in the progress of PCOS. The main purpose of this review is to provide the research background and some relevant suggestions for our future work in autophagy and help us better explore the pathogenesis and autophagy mechanisms of PCOS. Furthermore, it will help us gain a new insight of the pathophysiology and treatment of PCOS.

Beyond apoptosis: evidence of other regulated cell death pathways in the ovary throughout development and life

BACKGROUND

Regulated cell death is a fundamental component of numerous physiological processes; spanning from organogenesis in utero, to normal cell turnover during adulthood, as well as the elimination of infected or damaged cells throughout life. Quality control through regulation of cell death pathways is particularly important in the germline, which is responsible for the generation of offspring. Women are born with their entire supply of germ cells, housed in functional units known as follicles. Follicles contain an oocyte, as well as specialized somatic granulosa cells essential for oocyte survival. Follicle loss-via regulated cell death-occurs throughout follicle development and life, and can be accelerated following exposure to various environmental and lifestyle factors. It is thought that the elimination of damaged follicles is necessary to ensure that only the best quality oocytes are available for reproduction.

OBJECTIVE AND RATIONALE

Understanding the precise factors involved in triggering and executing follicle death is crucial to uncovering how follicle endowment is initially determined, as well as how follicle number is maintained throughout puberty, reproductive life, and ovarian ageing in women. Apoptosis is established as essential for ovarian homeostasis at all stages of development and life. However, involvement of other cell death pathways in the ovary is less established. This review aims to summarize the most recent literature on cell death regulators in the ovary, with a particular focus on non-apoptotic pathways and their functions throughout the discrete stages of ovarian development and reproductive life.

SEARCH METHODS

Comprehensive literature searches were carried out using PubMed and Google Scholar for human, animal, and cellular studies published until August 2022 using the following search terms: oogenesis, follicle formation, follicle atresia, oocyte loss, oocyte apoptosis, regulated cell death in the ovary, non-apoptotic cell death in the ovary, premature ovarian insufficiency, primordial follicles, oocyte quality control, granulosa cell death, autophagy in the ovary, autophagy in oocytes, necroptosis in the ovary, necroptosis in oocytes, pyroptosis in the ovary, pyroptosis in oocytes, parthanatos in the ovary, and parthanatos in oocytes.

OUTCOMES

Numerous regulated cell death pathways operate in mammalian cells, including apoptosis, autophagic cell death, necroptosis, and pyroptosis. However, our understanding of the distinct cell death mediators in each ovarian cell type and follicle class across the different stages of life remains the source of ongoing investigation. Here, we highlight recent evidence for the contribution of non-apoptotic pathways to ovarian development and function. In particular, we discuss the involvement of autophagy during follicle formation and the role of autophagic cell death, necroptosis, pyroptosis, and parthanatos during follicle atresia, particularly in response to physiological stressors (e.g. oxidative stress).

WIDER IMPLICATIONS

Improved knowledge of the roles of each regulated cell death pathway in the ovary is vital for understanding ovarian development, as well as maintenance of ovarian function throughout the lifespan. This information is pertinent not only to our understanding of endocrine health, reproductive health, and fertility in women but also to enable identification of novel fertility preservation targets.

Long-Term Copper Exposure Induced Excessive Autophagy of the Porcine Spleen

Copper (Cu) is one of the essential trace elements and is widespread in the environment. However, excessive exposure will induce toxicity in animals. To investigate the potential mechanisms of Cu-induced porcine spleen toxicity, sixty 30-day-old pigs were randomly divided into three groups. The control group was fed a basal diet and two treatment groups were separately fed the diet with 125 mg/kg and 250 mg/kg of Cu for 80 days. The result of immunohistochemical staining showed that the autophagy marker p62 was significantly increased under Cu exposure, and the immunofluorescence results showed the same trend as LC33-. Meanwhile, Cu intensified autophagy by increasing the expression levels of autophagy-related genes and proteins (LC3, p62, ATG5, Beclin1, and PINK1). These results suggested that long-term Cu exposure induced excessive autophagy in the porcine spleen, laying the groundwork for future studies on Cu-induced immunotoxicity in the spleen and increasing the public safety awareness of the excessive Cu-induced contamination in the environment.

MiR-34a-5p promotes autophagy and apoptosis of ovarian granulosa cells via the Hippo-YAP signaling pathway by targeting LEF1 in chicken

Follicular atresia is a natural physiological phenomenon in poultry reproduction. It is well known that follicular atresia is caused by both autophagy and apoptosis of granulosa cells. In current experiment, we evaluated the function of miR-34a-5p on autophagy and apoptosis in chicken follicular atresia. First, the follicular atresia model of chicken was successfully constructed by subcutaneous injection of tamoxifen (TMX), and found the expression of miR-34a-5p in the atresia follicles obviously increased. Then, we confirmed that miR-34a-5p accelerates autophagy and apoptosis of chicken granulose cells in vitro, and miR-34a-5p could induce apoptosis by mediating autophagy. Mechanistically, lymphoid enhancer binding factor 1 (LEF1) was deemed as a target gene for miR-34a-5p. On the contrary, LEF1 overexpression attenuated the autophagy and apoptosis of chicken granular cells. In addition, it was confirmed that the miR-34a-5p/LEF1 axis plays a regulatory role in chicken granulosa cells by mediating the Hippo-YAP signaling pathway. Taken together, this study demonstrated that miR-34a-5p contributes to autophagy and apoptosis of chicken follicular granulosa cells by targeting LEF1 to mediate the Hippo-YAP signaling pathway.

Trehalose Suppresses Lysosomal Anomalies in Supporting Cells of Oocytes and Maintains Female Fertility

Supporting cells of oocytes, i.e., cumulus cells, control oocyte quality, which determines fertilization success. Therefore, the transformation of mature and immature cumulus cells (MCCs and ICCs, respectively) into dysmature cumulus cells (DCCs) with dead characteristics deteriorates oocyte quality. However, the molecular basis for this transformation remains unclear. Here, we explored the link between autophagic decline and cumulus transformation using cumulus cells from patients with infertility, female mice, and human granulosa cell-derived KGN cell lines. When human cumulus cells were labeled with LysoTracker probes, fluorescence corresponding to lysosomes was enhanced in DCCs compared to that in MCCs and ICCs. Similarly, treatment with the autophagy inhibitor chloroquine elevated LysoTracker fluorescence in both mouse cumulus cells and KGN cells, subsequently suppressing ovulation in female mice. Electron microscopy analysis revealed the proliferation of abnormal lysosomes in chloroquine-treated KGN cells. Conversely, the addition of an autophagy inducer, trehalose, suppressed chloroquine-driven problematic lysosomal anomalies and ameliorated ovulation problems. Our results suggest that autophagy maintains the healthy state of the supporting cells of human oocytes by suppressing the formation of lysosomes. Thus, our results provide insights into the therapeutic effects of trehalose on female fertility.

Effects of quercetin on tenderness, apoptotic and autophagy signalling in chickens during post-mortem ageing

The effect of quercetin on chicken breast muscle tenderness and the associated mechanism were investigated. The results indicated that quercetin significantly decreased the shear force and increased the myofibril fragmentation index (MFI). Haematoxylin-eosin-stained images showed that the internal structure of myofibril bundles in the quercetin-treated group was obviously degraded. Transmission electron microscopy showed that the myofibril structure, especially the M-line and A-band, was seriously degraded after quercetin treatment. Furthermore, quercetin treatment increased caspase-3 activity and the Bax/Bcl-2 ratio. The intensity of BiP, XBP1 and p-IRE1/IRE1 ratio increased significantly, and caspase-12 was activated. In addition, quercetin induced the transition from LC3I to LC3II and increased the expression of ATG7 and Beclin-1. The PI3K/Akt/mTOR signalling pathway was involved in the induction of autophagy and apoptosis by quercetin. These results indicated quercetin can promote meat tenderization, and activate apoptosis and autophagy pathways during post-mortem ageing.

Role of autophagy in follicular development and maintenance of primordial follicular pool in the ovary

The reproductive life span of the organism mainly depends on follicular development that maintains the primordial follicle pool in the cohort of follicles within the ovary. The total count of primordial follicles decreases with age due to ovulation and follicular atresia. Follicular atresia, a process of ovarian follicles degradation, mainly occurs via apoptosis, but recent studies also favor autophagy existence. Autophagy is a cellular and energy homeostatic response that helps to maintain the number of healthy primordial follicles, germ cell survival, and removal of corpus luteum remnants. But the excessive autophagic cell death changes both the quality and quantity of oocytes that ultimately affect female reproductive health. Autophagy regulation occurs by various autophagy-regulated genes like BECN1 and LC3-II (autophagy marker genes). Their abnormal regulation or mutation highly influences follicular development by alteration of primordial follicles formation, the decline in oocytes count, and germ cell loss. Various classical signaling pathways such as PI3K/AKT/mTOR, MAPK/ERK1/2, AMPK, and IRE1 are involved in granulosa and oocytes autophagy, while mTOR signaling is the primary mechanism. Along with basal level autophagy, chemical/hormone/stress-mediated autophagy also affects follicular development and female reproduction. In this review, we have primarily focused on granulosa cell and oocytes' autophagy, mechanism, and the role of autophagy determining marker genes in follicular development.

Autophagy in ovary and polycystic ovary syndrome: role, dispute and future perspective

Polycystic ovary syndrome (PCOS) is a unification of endocrine and metabolic disorders and has become immensely prevalent among women of fertile age. The prime organ affected in PCOS is the ovary and its distressed functioning elicits disturbed reproductive outcomes. In the ovary, macroautophagy/autophagy performs a pivotal role in directing the chain of events starting from oocytes origin until its fertilization. Recent discoveries demonstrate a significant role of autophagy in the pathogenesis of PCOS. Defective autophagy in the follicular cells during different stages of follicles is observed in the PCOS ovary. Exploring different autophagy pathways provides a platform for predicting the possible cause of altered ovarian physiology in PCOS. In this review, we have emphasized autophagy's role in governing follicular development under normal circumstances and in PCOS, including significant abnormalities associated with PCOS such as anovulation, hyperandrogenemia, metabolic disturbances, and related abnormality. So far, few studies have linked autophagy and PCOS and propose its essential role in PCOS progression. However, detailed knowledge in this area is lacking. Here we have summarized the latest knowledge related to autophagy associated with PCOS. This review's main objective is to provide a background of autophagy in the ovary, its possible connection with PCOS and suggested a novel proposal for future studies to aid a better understanding of PCOS pathogenesis.Abbreviations: AE: androgen excess; AF: antral follicle; AKT/PKB: AKT serine/threonine kinase; AMH: anti-Mullerian hormone; AMPK: AMP-activated protein kinase; ATG: autophagy-related; BCL2: BCL2 apoptosis regulator; BECN1: beclin 1; BMP: bone morphogenetic protein; CASP3: caspase 3; CL: corpus luteum; CYP17A1/P450C17: cytochrome P450 family 17 subfamily A member 1; CYP19A1: cytochrome P450 family 19 subfamily A member 1; DHEA: dehydroepiandrosterone; EH: endometrial hyperplasia; FF: follicular fluid; FOXO: forkhead box O; FSH: follicle stimulating hormone; GC: granulosa cell; GDF: growth differentiation factor; HA: hyperandrogenemia; HMGB1: high mobility group box 1; IGF1: insulin like growth factor 1; INS: insulin; IR: insulin resistance; LHCGR/LHR: luteinizing hormone/choriogonadotropin receptor; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MAPK/ERK: mitogen-activated protein kinase; MAPK8/JNK: mitogen-activated protein kinase 8; MTOR: mechanistic target of rapamycin kinase; MTORC: mechanistic target of rapamycin complex; NAFLD: nonalcoholic fatty liver disease; NFKB: nuclear factor kappa B; OLR1/LOX-1: oxidized low density lipoprotein receptor 1; oxLDL: oxidized low-density lipoproteins; PA: palmitic acid; PCOS: polycystic ovary syndrome; PF: primary follicle; PGC: primordial germ cell; PI3K: phosphoinositide 3-kinase; PMF: primordial follicle; ROS: reactive oxygen species; RP: resting pool; SIRT1: sirtuin 1; SQSTM1/p62: sequestosome 1; T2DM: type 2 diabetes mellitus; TC: theca cell; TUG1: taurine up-regulated 1.

Pyraclostrobin induced AMPK/mTOR pathways mediated autophagy in RAW264.7 macrophages

Pyraclostrobin(PCT) is a highly effective and broad-spectrum strobilurin fungicide. The mode action of PCT is inhibiting mitochondrial respiration. With the widespread use of PCT in preventing and controlling crop diseases, its potential safety risks to mammals have gradually attracted attention. This paper focuses on the cytotoxicity of PCT and its molecular mechanism, RAW264.7 macrophages were selected as a research model and conducted systematic toxicology studies in vitro, including MTT assay, colony formation assay, alkaline comet assay, fluorescent staining, ATP assay and Western blotting. The results revealed that PCT decreased viability and inhibited the proliferation of RAW264.7 cells in a concentration- dependent manner. Interestingly, PCT induced DNA damage, the resulting autophagosome, the accumulation of Beclin-1, the reduction of p62, the translocation and the formation of LC3-II. Furthermore, the results showed that PCT-induced the production of excessive ROS, leading to mitochondrial permeability transition pore (mPTP) opening, ATP depletion, and the elimination of mitochondria by autophagy. Furthermore, PCT treatment group significantly enhanced the phosphorylation level of AMPK, decreased the mTOR and p70s6k phosphorylation levels and activated the AMPK/mTOR signaling pathway in RAW264.7 cells. In conclusion, these results showed that PCT induced autophagy in the RAW264.7 cells might potentially have risks to mammal safety.

Primate-specific POTE-actin gene could play a role in human folliculogenesis by controlling the proliferation of granulosa cells

Patients with primary ovarian insufficiency (POI) often have a high prevalence of autoimmune disorders. To identify antigenic molecules associated with ovarian autoimmunity, we performed immunoprecipitation (IP) screening using serum from patients with POI and the established human granulosa cell line (HGrC1). POTE ankyrin domain family member E (POTEE) and POTE ankyrin domain family member F (POTEF), proteins specific to primates, were identified as candidate antigens. Using immunohistochemistry (IHC) with human ovarian tissue, POTEE or POTEF was weakly seen in the granulosa cells (GCs) of primordial follicles and primary follicles, and strongly in large antral follicles and luteal cells. Interestingly, no signals were detected in growing GCs in secondary, preantral, and small antral follicles. Thus, to explore the function of POTEE and POTEF in human folliculogenesis, we established HGrC1 cell lines with drug-inducible expression of POTEF. Expression of POTEF significantly suppressed cell proliferation in HGrC1 cells. Furthermore, chaperonin containing TCP-1 complex (CCT) components, which affect folding proteins required for cell proliferation, was bound to the actin domain of POTEF protein. Although CCT is normally localized only around the Golgi apparatus, TCP-1α, a component of CCT, co-migrated closer to the cell membrane when POTEF expression was induced. These data suggest that the interaction between POTEF and CCT components impairs the usual function of CCT during cell growth. In addition, over-accumulation of POTEF in HGrC1 cells leads to autophagic failure. It was recently reported that knockout of an autophagic gene in mice leads to a phenotype similar to human POI. These results suggested that a proper amount of POTEF is required for the maintenance of GCs in follicle pools, whereas POTEF overaccumulation might be involved in follicle atresia and the development of POI. We also showed the possibility that POTEF could be an antigen involved in ovarian autoimmunity.

Chronic endometritis and altered embryo implantation: a unified pathophysiological theory from a literature systematic review

PURPOSE

Chronic endometritis (CE) is a frequent hysteroscopic and histological finding which affects embryo transfer implantation during IVF-ICSI cycles. In particular, CE impairs proper decidualization and, subsequently, implantation. Although this correlation has been clearly clarified, a pathophysiological explanation assembling all the studies performed has not been elucidated yet. For this reason, we have structured a systematic review considering all the original articles that evaluated a pathological element involved in CE and implantation impairment.

METHODS

The authors searched electronic databases and, after screening, collected 15 original articles. These were fully scanned and used to create a summary pathway.

RESULTS

CE is primarily caused by infections, which lead to a specific cytokine and leukocyte pattern in order to prepare the uterus to fight the noxa. In particular, the immunosuppression requested for a proper semi-allogenic embryo transfer implantation is converted into an immunoreaction, which hampers correct embryo implantation. Moreover, endometrial vascularization is affected and both irregular vessel density and luminal thickening and thrombosis reduce what we have first identified as endometrial flow reserve. Finally, incorrect uterine wave propagation could affect embryo contact with decidua.

CONCLUSION

This is the first summary of evidence on CE pathophysiology and its relationship with infertility. Understanding the CE pathophysiology could improve our knowledge in embryo transfer success.

Next-Generation Sequencing Reveals Downregulation of the Wnt Signaling Pathway in Human Dysmature Cumulus Cells as a Hallmark for Evaluating Oocyte Quality

Background: Dysmature cumulus cells are lower fertilization rates and abnormalities in embryonic development compared to maturation cumulus cells. Morphological evaluation of cumulus–oocyte complexes (COCs) considered the possibility that differences may also be found in gene expression. Purpose: To identify hallmarks for evaluating oocyte quality by investigating gene expression patterns in human cumulus cells surrounding oocytes. Methods: Cumulus cells were obtained from the cumulus–oocyte complex of infertile women treated with assisted reproductive technology. Based on maturity level, the cumulus cells were classified into two categories, i.e., dysmature cumulus cell (DCC) and maturation cumulus cell. DCCs were subjected to gene expression analysis using next-generation sequencing and compared with COCs that are in the process of maturation as controls. Results: The expression levels of genes involved in the Wnt signal/β-catenin pathway were significantly reduced in DCCs compared with those in control cells. Moreover, the expression levels of genes involved in multiple pathways associated with apoptosis were also significantly reduced compared with those in control cells. Conclusions: DCCs showed significant decreases in apoptosis- and Wnt/β-catenin signaling-associated gene expression. DCCs could be classified by morphological evaluation, and the method described in this study may be useful as an oocyte quality estimation tool.

Keap1 inhibition sensitizes head and neck squamous cell carcinoma cells to ionizing radiation via impaired non-homologous end joining and induced autophagy

The function of Keap1 (Kelch-like ECH-associated protein 1), a sensor of oxidative and electrophilic stress, in the radiosensitivity of cancer cells remains elusive. Here, we investigated the effects of pharmacological inhibition of Keap1 with ML344 on radiosensitivity, DNA double-strand break (DSB) repair and autophagy in head and neck squamous cell carcinoma (HNSCC) cell lines. Our data demonstrate that Keap1 inhibition enhances HNSCC cell radiosensitivity. Despite elevated, Nrf2-dependent activity of non-homologous end joining (NHEJ)-related DNA repair, Keap1 inhibition seems to impair DSB repair through delayed phosphorylation of DNA-PKcs. Moreover, Keap1 inhibition elicited autophagy and increased p62 levels when combined with X-ray irradiation. Our findings suggest HNSCC cell radiosensitivity, NHEJ-mediated DSB repair, and autophagy to be co-regulated by Keap1.

Knockdown of Atg7 Induces Nuclear-LC3 Dependent Apoptosis and Augments Chemotherapy in Colorectal Cancer Cells

Autophagy is a catabolic process that enables cells to degrade obsolete content and refuel energy depots. In colorectal cancer (CRC) autophagy has been shown to promote tumorigenesis through energy delivery in the condition of uncontrolled proliferation. With this study, we aimed at evaluating whether autophagy sustains CRC cell viability and if it impacts therapy resistance. Initially, a colorectal cancer tissue micro array, containing mucosa (n = 10), adenoma (n = 18) and adenocarcinoma (n = 49) spots, was stained for expression of essential autophagy proteins LC3b, Atg7, p62 and Beclin-1. Subsequently, central autophagy proteins were downregulated in CRC cells using siRNA technology. Viability assays, flow cytometry and immunoblotting were performed and three-dimensional cell culture was utilized to study autophagy in a tissue mimicking environment. In our study we found an upregulation of Atg7 in CRC. Furthermore, we identified Atg7 as crucial factor within the autophagy network for CRC cell viability. Its disruption induced cell death via triggering apoptosis and in combination with conventional chemotherapy it exerted synergistic effects in inducing CRC cell death. Cell death was strictly dependent on nuclear LC3b, since simultaneous knockdown of Atg7 and LC3b completely restored viability. This study unravels a novel cell death preventing function of Atg7 in interaction with LC3b, thereby unmasking a promising therapeutic target in CRC.