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448 result(s) for "Sang, Qing"
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Genetic factors as potential molecular markers of human oocyte and embryo quality
Successful human reproduction requires gamete maturation, fertilization, and early embryonic development. Human oocyte maturation includes nuclear and cytoplasmic maturation, and abnormalities in the process will lead to infertility and recurrent failure of IVF/ICSI attempts. In addition, the quality of oocytes/embryos in the clinic can only be determined by morphological markers, and there is currently a lack of molecular markers for determining oocyte quality. As the number of patients undergoing IVF/ICSI has increased, many patients have been identified with recurrent IVF/ICSI failure. However, the genetic basis behind this phenotype remains largely unknown. In recent years, a few mutant genes have been identified by us and others, which provide potential molecular markers for determining the quality of oocytes/embryos. In this review, we outline the genetic determinants of abnormalities in the processes of oocyte maturation, fertilization, and early embryonic development. Currently, 16 genes (PATL2, TUBB8, TRIP13, ZP1, ZP2, ZP3, PANX1, TLE6, WEE2, CDC20, BTG4, PADI6, NLRP2, NLRP5, KHDC3L, and REC114) have been reported to be the causes of oocyte maturation arrest, fertilization failure, embryonic arrest, and preimplantation embryonic lethality. These abnormalities mainly have Mendelian inheritance patterns, including both dominant inheritance and recessive inheritance, although in some cases de novo mutations have also appeared. In this review, we will introduce the effects of each gene in the specific processes of human early reproduction and will summarize all known variants in these genes and their corresponding phenotypes. Variants in some genes have specific effects on certain steps in the early human reproductive processes, while other variants result in a spectrum of phenotypes. These variants and genetic markers will lay the foundation for individualized genetic counseling and potential treatments for patients and will be the target for precision treatments in reproductive medicine.
Functionalization of Brain Region-specific Spheroids with Isogenic Microglia-like Cells
Current brain spheroids or organoids derived from human induced pluripotent stem cells (hiPSCs) still lack a microglia component, the resident immune cells in the brain. The objective of this study is to engineer brain region-specific organoids from hiPSCs incorporated with isogenic microglia-like cells in order to enhance immune function. In this study, microglia-like cells were derived from hiPSCs using a simplified protocol with stage-wise growth factor induction, which expressed several phenotypic markers, including CD11b, IBA-1, CX3CR1, and P2RY12, and phagocytosed micron-size super-paramagnetic iron oxides. The derived cells were able to upregulate pro-inflammatory gene (TNF-α) and secrete anti-inflammatory cytokines (i.e., VEGF, TGF-β1, and PGE2) when stimulated with amyloid β42 oligomers, lipopolysaccharides, or dexamethasone. The derived isogenic dorsal cortical (higher expression of TBR1 and PAX6) and ventral (higher expression of NKX2.1 and PROX1) spheroids/organoids displayed action potentials and synaptic activities. Co-culturing the microglia-like cells (MG) with the dorsal (D) or ventral (V) organoids showed differential migration ability, intracellular Ca 2+ signaling, and the response to pro-inflammatory stimuli (V-MG group had higher TNF-α and TREM2 expression). Transcriptome analysis exhibited 37 microglia-related genes that were differentially expressed in MG and D-MG groups. In addition, the hybrid D-MG spheroids exhibited higher levels of immunoreceptor genes in activating members, but the MG group contained higher levels for most of genes in inhibitory members (except SIGLEC5 and CD200). This study should advance our understanding of the microglia function in brain-like tissue and establish a transformative approach to modulate cellular microenvironment toward the goal of treating various neurological disorders.
Molecular and Cellular Effects of Microplastics and Nanoplastics: Focus on Inflammation and Senescence
Microplastics and nanoplastics (MNPs) are ubiquitous environmental contaminants. Their prevalence, persistence, and increasing industrial production have led to questions about their long-term impact on human and animal health. This narrative review describes the effects of MNPs on oxidative stress, inflammation, and aging. Exposure to MNPs leads to increased production of reactive oxygen species (ROS) across multiple experimental models, including cell lines, organoids, and animal systems. ROS can cause damage to cellular macromolecules such as DNA, proteins, and lipids. Direct interaction between MNPs and immune cells or an indirect result of oxidative stress-mediated cellular damage may lead to increased production of pro-inflammatory cytokines throughout different MNP-exposure conditions. This inflammatory response is a common feature in the pathogenesis of neurodegenerative, cardiovascular, and other age-related diseases. MNPs also act as cell senescence inducers by promoting mitochondrial dysfunction, impairing autophagy, and activating DNA damage responses, exacerbating cellular aging altogether. Increased senescence of reproductive cells and transfer of MNPs/induced damages from parents to offspring in animals further corroborates the transgenerational health risks of the tiny particles. This review aims to provoke a deeper investigation into the notorious effects these pervasive particles may have on human well-being and longevity.
Matrix metalloproteinase inhibitors as therapy for inflammatory and vascular diseases
Key Points Historically, testing matrix metalloproteinase inhibitors (MMPIs) for the therapy of invasive or metastatic cancers has not yielded the expected beneficial results, but has had a positive effect on the development of MMPIs. However, cancers are genetically unstable and more heterogeneous, which implies that the treatment outcomes are less predictable than in inflammation. In addition, it is not clear whether inflammatory cell infiltrations in cancers have beneficial or detrimental roles for the host. Seminal work on inflammation and vascular MMP biology is reviewed here and indicates a further need to test MMPIs in established and new animal models of inflammation, infection and ischaemia. In analogy with inducible cyclooxygenase as a drug target, inducible MMPs are preferred above constitutive or homeostatic enzymes to target with MMPIs in inflammatory and vascular diseases. In contrast to microbiological enzyme targets, MMPs are host enzymes. This implies that with MMPI treatment, normal physiological functions will be blocked with subsequent side effects. Such side effects are, however, tolerable in life-saving situations. In acute life-threatening inflammation, oral use and high selectivity of MMPIs — set as unreached double challenges in the development of MMPIs for cancer treatment — are not necessary. This implies that obligately parenteral drugs, including recombinant proteins (for example, interferon affecting the tissue inhibitor of matrix metalloproteinase (TIMP)/MMP balance) and monoclonal antibodies that inhibit MMPs and peptide MMPIs, are worthwhile to develop and to combine. For chronic inflammatory diseases, the picture is completely different to acute inflammation. High selectivity and oral availability are in demand. These diseases constitute important targets for the pharmaceutical industry. Therefore, major basic and animal research efforts need to be continued and extended. For vascular diseases, the primary question of whether to use MMPIs relates to the aetiology of the pathology and the localization of the injury. Acute ischaemic insults might benefit from MMPI treatment by the rescue of tissue in the penumbra zones. Long-term treatment of chronic ischaemia with MMPIs will necessitate the development of novel oral, highly selective MMPIs. Studies with Mmp -knockout mice contribute to novel insights and are a reasonable indicator to discover whether selective MMPIs have potential benefit. However, acute and chronic inflammatory and vascular animal models have not been sufficiently studied, yielded sometimes discrepant data and are prone to compensatory mechanisms and strain-specific differences. The development of inducible and multiple Mmp -knockout mice, studies of various strain backcrosses and better complementation of data might overcome some of these problems. From animal models of organ-specific and tissue-specific acute inflammation and ischaemia the general view is that specific MMPs dominate in the pathogenesis, for example, MMP12 in lung emphysema and MMP9 in acute ischaemia and multiple sclerosis. MMP9 has been studied most as an inducible drug target and many (unspecific) inhibitors against MMP9 have been synthesized and are reviewed. Efforts to generate the complete, rather than partial, MMP crystal structures, molecular modelling and empirical inhibitor screening studies need to be combined with extensive animal experiments for the discovery of novel highly specific and therapeutically active inhibitors. For development of synthetic MMPIs, high-affinity zinc-binding groups, mainly hydroxamates, have been preferred. With the discovery of zinc-containing ADAMs (a disintegrin and metalloproteinases) and ADAMTSs (ADAMs with a thrombospondin motif) and their evolving roles in biology and pathology, other determinants for the binding of inhibitors to MMPs, including the active-site pockets and exosites, need to be further investigated. Protein domain specificity, pH dependence of carboxylates and better substrate-based design might be exploited in future directions for MMPI development. Although clinical trials using matrix metalloproteinase inhibitors (MMPIs) for cancer therapy were disappointing, Opdenakker and colleagues discuss how the use of selective MMPIs might lead to new treatments for acute and chronic inflammatory and vascular diseases. Matrix metalloproteinases (MMPs) have outgrown the field of extracellular-matrix biology and have progressed towards being important regulatory molecules in cancer and inflammation. This rise in status was accompanied by the development of various classes of inhibitors. Although clinical trials with synthetic inhibitors for the treatment of cancer were disappointing, recent data indicate that the use of selective inhibitors might lead to new therapies for acute and chronic inflammatory and vascular diseases. In this Review, we compare the major classes of MMP inhibitors and advocate that future drug discovery should be based on crucial insights into the differential roles of specific MMPs in pathophysiology obtained with animal models, including knockout studies.
Immune landscape of human prostate cancer: immune evasion mechanisms and biomarkers for personalized immunotherapy
Background Despite recent advances in cancer immunotherapy, the efficacy of these therapies for the treatment of human prostate cancer patients is low due to the complex immune evasion mechanisms (IEMs) of prostate cancer and the lack of predictive biomarkers for patient responses. Methods To understand the IEMs in prostate cancer and apply such understanding to the design of personalized immunotherapies, we analyzed the RNA-seq data for prostate adenocarcinoma from The Cancer Genome Atlas (TCGA) using a combination of biclustering, differential expression analysis, immune cell typing, and machine learning methods. Results The integrative analysis identified eight clusters with different IEM combinations and predictive biomarkers for each immune evasion cluster. Prostate tumors employ different combinations of IEMs. The majority of prostate cancer patients were identified with immunological ignorance (89.8%), upregulated cytotoxic T lymphocyte-associated protein 4 (CTLA4) (58.8%), and upregulated decoy receptor 3 (DcR3) (51.6%). Among patients with immunologic ignorance, 41.4% displayed upregulated DcR3 expression, 43.26% had upregulated CTLA4, and 11.4% had a combination of all three mechanisms. Since upregulated programmed cell death 1 (PD-1) and/or CTLA4 often co-occur with other IEMs, these results provide a plausible explanation for the failure of immune checkpoint inhibitor monotherapy for prostate cancer. Conclusion These findings indicate that human prostate cancer specimens are mostly immunologically cold tumors that do not respond well to mono-immunotherapy. With such identified biomarkers, more precise treatment strategies can be developed to improve therapeutic efficacy through a greater understanding of a patient’s immune evasion mechanisms.
Mutations in TUBB8 and Human Oocyte Meiotic Arrest
Mutations in a tubulin gene caused infertility due to oocyte arrest in about a third of families tested. The investigators found that the mutant tubulins wreak havoc on microtubule assembly in the oocyte. Successful human reproduction starts when a metaphase II oocyte fuses with a sperm cell to form a fertilized egg. In human oocytes, the meiotic cell cycle begins in the neonatal ovary and pauses at prophase I of meiosis until puberty, when a surge of luteinizing hormone stimulates the resumption of meiosis and ovulation. This leads to progression of the oocyte from metaphase I to metaphase II. 1 – 3 Oocytes arrested in prophase I have an intact nucleus, termed the germinal vesicle, whereas oocytes that have resumed meiosis are characterized by the breakdown of the germinal vesicle. After germinal-vesicle breakdown, metaphase I . . .
MOS is a novel genetic marker for human early embryonic arrest and fragmentation
Early embryonic arrest and fragmentation (EEAF) is a common phenotype observed in in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles. The phenotype causes female infertility and recurrent failed IVF/ICSI attempts. However, the molecular mechanisms behind EEAF remain largely unknown. In this issue of EMBO Molecular Medicine , Zhang et al (2021) present the novel causative gene MOS in patients with the EEAF phenotype. The relationship between MOS variants and human EEAF is comprehensively established through a series of in vitro and in vivo experiments, thus clarifying the role of MOS during human oocyte maturation and early embryo development. These findings suggest that MOS is a new diagnostic marker of EEAF and is a potential therapeutic target for treatment of EEAF patients. Graphical Abstract L. Wang and Q. Sang discuss the study by Zhang et al (in this issue of EMBO Mol Med ) that reports Moloney sarcoma oncogene (MOS) as a novel genetic marker for early embryonic arrest and fragmentation.
Cytochrome P450-2D6: A novel biomarker in liver cancer health disparity
Liver cancer morbidity and mortality rates differ among ethnic groups. In the United States, the burden of liver cancer in Asian Americans (AS) is higher compared to Caucasian Americans (CA). Research on liver cancer health disparities has mainly focused on environmental and socioeconomic factors yet has ignored the genotypic differences among various racial/ethnic groups. This lack of molecular level understanding has hindered the development of personalized medical approaches for liver cancer treatment. To understand the genetic heterogeneity of liver cancer between AS and CA, we performed a systematic analysis of RNA-seq data of AS and CA patients from The Cancer Genome Atlas (TCGA). We used four differential gene expression analysis packages; DESeq2, limma, edgeR, and Superdelta2, to identify the differentially expressed genes. Our analysis identified cytochrome P450-2D6 enzyme (CYP2D6) as the gene with the greatest differential expression with higher levels in AS compared to CA. To scrutinize the underlying mechanism of CYP2D6, Ingenuity Pathway Analysis (IPA) and Cytoscape were conducted and found hepatocyte nuclear factor-4α (HNF4A) and interleukin-6 (IL6) in direct association with CYP2D6. IL6 is downregulated in AS compared to CA, while HNF4A is not significantly different. Herein, we report that CYP2D6 may serve as a putative biomarker in liver cancer health disparities. Its negative association with IL6 proclaims an intricate relationship between CYP2D6 and inflammation in the ethnic differences seen in AS and CA liver cancer patients. The goal of the present study was to understand how genetic factors may contribute to the interethnic variability of liver cancer prevalence and outcomes in AS and CA patients. Identifying ethnic-specific genes may help ameliorate detection, diagnosis, surveillance, and treatments of liver cancer, as well as reduce disease-related incidence and mortality rates in the vulnerable population.
Secretome analysis reveals upregulated granzyme B in human androgen-repressed prostate cancer cells with mesenchymal and invasive phenotype
Epithelial-mesenchymal transition (EMT) is a critical early step in cancer metastasis and a complex process that involves multiple factors. In this study, we used proteomics approaches to investigate the secreted proteins (secretome) of paired human androgen-repressed prostate cancer (ARCaP) cell lines, representing the epithelial (ARCaP-E) and mesenchymal (ARCaP-M) phenotypes. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses showed high levels of proteins involved in bone remodeling and extracellular matrix degradation in the ARCaP-M cells, consistent with the bone metastasis phenotype. Furthermore, LC-MS/MS showed a significantly higher level of the serine protease granzyme B (GZMB) in ARCaP-M conditioned media (CM) compared to that of ARCaP-E. Using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) to detect mRNA and Western blot to detect protein expression, we further demonstrated that the GZMB gene was expressed by ARCaP-M and the protein was secreted extracellularly. ARCaP-M cells with GZMB gene knockdown using small interfering RNA (siRNA) have markedly reduced invasiveness as demonstrated by the Matrigel invasion assay in comparison with the scrambled siRNA negative control. This study reports that GZMB secretion by mesenchymal-like androgen-repressed human prostate cancer cells promotes invasion, suggesting a possible extracellular role for GZMB in addition to its classic role in immune cell-mediated cytotoxicity.
Expanding the genetic and phenotypic spectrum of female infertility caused by TLE6 mutations
PurposeThe present study was intended to identify genetic causes of infertile patients with recurrent failure of in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) attempts.MethodsInfertile patients with recurrent IVF/ICSI failure from Shanghai Ji Ai Genetics & IVF Institute and the Ninth Hospital affiliated with Shanghai Jiao Tong University were recruited. Genomic DNA samples were extracted from their peripheral blood. Whole-exome sequencing and Sanger validation were performed to identify candidate variants.ResultsWe identified novel transducin-like enhancer of split 6 (TLE6) gene mutations in three patients with recurrent IVF/ICSI failure. One patient carried a homozygous missense mutation (c.1226G>A; p.Arg409Gln) with subsequent fertilization failure, while the other two patients carried either a homozygous missense mutation (c.1621G>A; p.Glu541Lys) or a compound heterozygous missense mutation (c.388G>A/c.1507G>A; p.Asp130Asn/p.Val503Ile) and had viable but low-quality embryos.ConclusionsOur study expands the mutational and phenotypic spectrum of TLE6 and suggests the important role of TLE6 during embryonic development. Our findings have implications for the genetic diagnosis of female infertility with recurrent IVF/ICSI failure.