Single-cell exome sequencing reveals single-nucleotide mutation characteristics of a kidney tumor.

Clear cell renal cell carcinoma (ccRCC) is the most common kidney cancer and has very few mutations that are shared between different patients. To better understand the intratumoral genetics underlying mutations of ccRCC, we carried out single-cell exome sequencing on a ccRCC tumor and its adjacent kidney tissue. Our data indicate that this tumor was unlikely to have resulted from mutations in VHL and PBRM1. Quantitative population genetic analysis indicates that the tumor did not contain any significant clonal subpopulations and also showed that mutations that had different allele frequencies within the population also had different mutation spectrums. Analyses of these data allowed us to delineate a detailed intratumoral genetic landscape at a single-cell level. Our pilot study demonstrates that ccRCC may be more genetically complex than previously thought and provides information that can lead to new ways to investigate individual tumors, with the aim of developing more effective cellular targeted therapies.

Comprehensive comparison of water quality risk and microbial ecology between new and old cast iron pipe distribution systems.

The effects of cast iron pipe corrosion on water quality risk and microbial ecology in drinking water distribution systems (DWDSs) were investigated. It was found that trihalomethane (THMs) concentration and antibiotic resistance genes (ARGs) increased sharply in the old DWDSs. Under the same residual chlorine concentration conditions, the adenosine triphosphate concentration in the effluent of old DWDSs (Eff-old) was significantly higher than that in the effluent of new DWDSs. Moreover, stronger bioflocculation ability and weaker hydrophobicity coexisted in the extracellular polymeric substances of Eff-old, meanwhile, iron particles could be well inserted into the structure of the biofilms to enhance the mechanical strength and stability of the biofilms, hence enhancing the formation of THMs. Old DWDSs significantly influenced the microbial community of bulk water and triggered stronger microbial antioxidant systems response, resulting in higher ARGs abundance. Corroded cast iron pipes induced a unique interaction system of biofilms, chlorine, and corrosion products. Therefore, as the age of cast iron pipes increases, the fluctuation of water quality and microbial ecology should be paid more attention to maintain the safety of tap water.

miR-216b Post-Transcriptionally Downregulates Oncogene KRAS and Inhibits Cell Proliferation and Invasion in Clear Cell Renal Cell Carcinoma.

BACKGROUND/AIMS: Increasing evidence has shown that miR-216b plays an important role in human cancer progression. However, little is known about the function of miR-216b in renal cell carcinoma. METHODS: The expression levels of miR-216b in renal cell carcinoma tissues and cell lines were examined by qRT-PCR. The biological role of miR-216b in renal cell carcinoma proliferation and/or metastasis was examined in vitro and in vivo. The target of miR-216b was identified by a dual-luciferase reporter assay. The expression level of KRAS protein was measured by western blotting. RESULTS: The expression of miR-216b was downregulated in clear cell renal cell carcinoma (ccRCC) cell lines and specimens compared to the adjacent normal tissues. Furthermore, miR-216b can bind to the 3'untranslated region (UTR) of KRAS and inhibit the expression of KRAS through translational repression. The in vitro study revealed that miR-216b attenuated ccRCC cell proliferation and invasion. Furthermore, in vivo study also showed that miR-216b suppressed tumor growth. MiR-216b exerted its tumor suppressor function through inhibiting the KRAS-related MAPK/ERK and PI3K/AKT pathways. CONCLUSION: Our findings provide, for the first time, significant clues regarding the role of miR-216b as a tumor suppressor by targeting KRAS in ccRCC.

Porcine IL-6, IL-1ß, and TNF-α regulate the expression of pro-inflammatory-related genes and tissue factor in human umbilical vein endothelial cells.

Whether porcine cytokines are induced after pig-to-primate xenotransplantation and activate human cells remains unknown. First, we investigated the regulation of porcine IL-6, IFN-γ, IL-1ß, and TNF-α in xenotransplantation using an in vitro model in which porcine aortic endothelial cells (PAECs) and porcine peripheral blood mononuclear cells (PBMCs) were stimulated with human serum. Downstream cytokines/chemokines were monitored. Pro-inflammatory cytokines (IL-6, IFN-γ, and IL-1ß) and chemokines (IL-8, MCP-1, and CXCL2) were upregulated in the both cell types. TNF-α was induced 10-fold in PAECs, but not in PBMCs. Then, we assessed the role of porcine IL-6, IFN-γ, IL-1ß, and TNF-α in xenotransplantation using western blotting and real-time PCR. Human umbilical vein endothelial cells (HUVECs) were selected as the target cells. Signaling pathways and downstream genes, such as those related to adhesion, inflammation, and coagulation, and chemokines were investigated. Porcine IL-1ß and TNF-α significantly activated NF-κB and P38, and STAT3 was activated by porcine IL-6 in HUVECs. The adhesion genes (E-selectin, VCAM-1, and ICAM-1), inflammatory cytokines (IL-6, IL-1ß, and TNF-α), chemokines (MCP-1 and IL-8), and the pro-coagulation gene (tissue factor) were upregulated by porcine IL-1ß and TNF-α. Porcine IL-6 increased the expression of ICAM-1, IL-6, MCP-1, and tissue factor, but decreased IL-8 expression slightly. Surprisingly, porcine IFN-γ could not activate STAT1 or regulate the expression of any of the above genes in HUVECs. In conclusion, these findings suggest that porcine IL-6, IL-1ß, and TNF-α activate HUVECs and regulate downstream genes expression, which may promote inflammation and coagulation response after xenotransplantation.

A metagenome-wide association study of gut microbiota in type 2 diabetes.

Assessment and characterization of gut microbiota has become a major research area in human disease, including type 2 diabetes, the most prevalent endocrine disease worldwide. To carry out analysis on gut microbial content in patients with type 2 diabetes, we developed a protocol for a metagenome-wide association study (MGWAS) and undertook a two-stage MGWAS based on deep shotgun sequencing of the gut microbial DNA from 345 Chinese individuals. We identified and validated approximately 60,000 type-2-diabetes-associated markers and established the concept of a metagenomic linkage group, enabling taxonomic species-level analyses. MGWAS analysis showed that patients with type 2 diabetes were characterized by a moderate degree of gut microbial dysbiosis, a decrease in the abundance of some universal butyrate-producing bacteria and an increase in various opportunistic pathogens, as well as an enrichment of other microbial functions conferring sulphate reduction and oxidative stress resistance. An analysis of 23 additional individuals demonstrated that these gut microbial markers might be useful for classifying type 2 diabetes.

Angiopoietin-1 and angiopoietin-2 protect porcine iliac endothelial cells from human antibody-mediated complement-dependent cytotoxicity through phosphatidylinositide 3-kinase/AKT pathway activation.

Cytokines play crucial roles in inflammation, but their role in xenotransplantation remains elusive. We assessed the role of several cytokines using an in vitro model of human antibody-mediated complement-dependent cytotoxicity (CDC). Recombinant human angiopoietin-1 (Ang-1) protected porcine iliac endothelial cells (PIECs) from human antibody-mediated CDC. Interestingly, human angiopoietin-2 (Ang-2) had a similar protective effect on PIECs. By flow cytometry analysis, the extent of human IgM and IgG binding to PIECs did not decrease when PIECs were exposed to Ang-1/Ang-2. The mRNA level of complement regulators (CD46, CD55, CD59) was not upregulated in PIECs treated with Ang-1/Ang-2, both of which activated the PI3K/AKT pathway in PIECs. Wortmannin, which inhibits phosphatidylinositide 3-kinase (PI3K), suppressed Ang-1/Ang-2-induced AKT phosphorylation and consequent Ang-1/Ang-2-mediated protection of PIECs in human antibody-mediated CDC model. Moreover, dominant negative AKT also suppressed Ang-1/Ang-2-mediated protection of PIECs in this model. In conclusion, our data suggest that human Ang-1/Ang-2 induces the protection of PIECs from human antibody-mediated CDC by activating the PI3K/AKT pathway. Ang-1/Ang-2 is likely to protect porcine endothelial cells and may be beneficial in xenotransplantation research.

Klotho attenuated antibody-mediated porcine endothelial cell activation and injury.

Long-term success in pig-to-primate xenotransplantation is currently hampered by acute vascular rejection (AVR), characterized by endothelial cell (EC) activation and injury. Klotho has anti-apoptotic, anti-inflammatory effects on EC and protects EC against reactive oxygen species, rendering klotho a promising molecule to control AVR. In this study, porcine ECs were pre-incubated with klotho and then exposed to xenoreactive antibodies and complement. Real-time PCR revealed that klotho suppressed antibody-induced pro-inflammatory gene expression of VCAM-1 and IL-1α. NF-κB activation, IκBα phosphorylation, was also attenuated by klotho administration. Furthermore, klotho induced in porcine EC resistance against complement-dependent cytotoxicity. Accompanying this change, the binding of IgG and IgM xenoreactive antibodies to porcine EC was decreased and the expression of anti-inflammatory gene HO-1 was upregulated. These findings indicated that klotho protein protected porcine EC from activation and injury caused by binding of xenoreactive antibodies and was a promising candidate molecule in a multitransgenic pig strategy for xenotransplantation.

Human IL-6, IL-17, IL-1ß, and TNF-α differently regulate the expression of pro-inflammatory related genes, tissue factor, and swine leukocyte antigen class I in porcine aortic endothelial cells.

BACKGROUND: Pro-inflammatory cytokines play important pathological effects in various diseases and allotransplantation; however, their pathological role in xenotransplantation remains elusive. In pig-to-human cell or organ transplantation, whether porcine cells or organs are activated by human cytokines or not as an important question needs to be investigated. METHODS: We investigated the effect of human IL-6, IFN-γ, IL-17, IL-1ß, and TNF-α in xenotransplantation using several in vitro models and porcine aortic endothelial cells (PAECs) as target cells. The downstream signaling pathways activated by these cytokines were studied with Western blotting, the regulation of the pro-inflammatory related genes and pro-coagulation factor were assessed using real-time PCR or enzyme-linked immunosorbent assay, and swine leukocyte antigen (SLA) class I and SLA class II DR were analyzed by flow cytometry. RESULTS: We found that NF-κB and mitogen-activated protein kinases (MAPKs) were activated by recombinant human IL-17 (rhIL-17), rhIL-1ß, and rhTNF-α, while rhIL-6 activated signal transducer and activator of transcription 3 (STAT3) in PAECs. The adhesion molecules (E-selectin, VCAM-1, and ICAM-1), pro-inflammatory gene (IL-6), chemokines (IL-8 and MCP-1), and the pro-coagulation factor (tissue factor) were induced by rhIL-17, rhIL-1ß, and rhTNF-α, while rhIL-6 only increased the expression of MCP-1 and tissue factor. Using flow cytometry analysis, SLA class I was upregulated in PAECs after exposure to rhIL-1ß and rhTNF-α, but not rhIL-6 or rhIL-17, whereas SLA class II DR could not be induced by rhIL-6, rhIL-17, rhIL-1ß, or rhTNF-α, although it could by recombinant porcine IFN-γ (rpIFN-γ). Although activation of PAECs by rhIL-17 alone was not strong, rhIL-17 combined with rhTNF-α amplified the expression of E-selectin, IL-6, and IL-8. Unexpectedly, we found that tocilizumab, a humanized anti-human IL-6 receptor antibody, could not block rhIL-6-mediated STAT3 activation in PAECs. Human IFN-γ could not activate STAT1 or induce the downstream gene expression in PAECs, which was consistent with a previous report. CONCLUSION: In conclusion, our data suggest that human IL-6, IL-17, IL-1ß, and TNF-α significantly activate PAECs and are likely to promote inflammation and coagulation reaction in response to xenograft.

Production of α1,3-galactosyltransferase and cytidine monophosphate-N-acetylneuraminic acid hydroxylase gene double-deficient pigs by CRISPR/Cas9 and handmade cloning.

Gene-knockout pigs hold great promise as a solution to the shortage of organs from donor animals for xenotransplantation. Several groups have generated gene-knockout pigs via clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) and somatic cell nuclear transfer (SCNT). Herein, we adopted a simple and micromanipulator-free method, handmade cloning (HMC) instead of SCNT, to generate double gene-knockout pigs. First, we applied the CRISPR/Cas9 system to target α1,3-galactosyltransferase (GGTA1) and cytidine monophosphate-N-acetylneuraminic acid hydroxylase (CMAH) genes simultaneously in porcine fetal fibroblast cells (PFFs), which were derived from wild-type Chinese domestic miniature Wuzhishan pigs. Cell colonies were obtained by screening and were identified by Surveyor assay and sequencing. Next, we chose the GGTA1/CMAH double-knockout (DKO) cells for HMC to produce piglets. As a result, we obtained 11 live bi-allelic GGTA1/CMAH DKO piglets with the identical phenotype. Compared to cells from GGTA1-knockout pigs, human antibody binding and antibody-mediated complement-dependent cytotoxicity were significantly reduced in cells from GGTA1/CMAH DKO pigs, which demonstrated that our pigs would exhibit reduced humoral rejection in xenotransplantation. These data suggested that the combination of CRISPR/Cas9 and HMC technology provided an efficient and new strategy for producing pigs with multiple genetic modifications.

A Comprehensive Investigation toward the Indicative Proteins of Bladder Cancer in Urine: From Surveying Cell Secretomes to Verifying Urine Proteins.

Urine is an ideal material to study the cancer-related protein biomarkers in bladder, whereas exploration to these candidates is confronting technique challenges. Herein, we propose a comprehensive strategy of searching the urine proteins related with bladder cancer. The strategy consists of three core combinations, screening the biomarker candidates in the secreted proteins derived from the bladder cancer cell lines and verifying them in patient urines, defining the differential proteins through two-dimensional electrophoresis (2DE) and isobaric tags for relative and absolute quantitation (iTRAQ) coupled with LC-MS/MS, and implementing quantitative proteomics of profiling and targeting analysis. With proteomic survey, a total of 700 proteins were found with their abundance of secreted proteins in cancer cell lines different from normal, while 87 proteins were identified in the urine samples. The multiple reaction monitoring (MRM)-based quantification was adapted in verifying the bladder cancer related proteins in individual urine samples, resulting in 10 differential urine proteins linked with the cancer. Of these candidates, receiver operating characteristic analysis revealed that the combination of CO3 and LDHB was more sensitive as the cancer indicator than other groups. The discovery of the bladder cancer indicators through our strategy has paved an avenue to further biomarker validation.

Downregulated ECRG4 is associated with poor prognosis in renal cell cancer and is regulated by promoter DNA methylation.

Esophageal cancer-related gene 4 (ECRG4) has been proposed as a putative tumor suppressor gene in several tumors. However, the role and regulation of ECRG4 in the pathogenesis of human renal cancer remain largely unknown. Our current study revealed that expression of ECRG4 is downregulated in renal cell lines and renal cancer tissues. ECRG4 expression was significantly associated with histological grade of tumors (p < 0.001), primary tumor stage (p = 0.017), and distant metastasis (p = 0.017). Low expression of ECRG4 was an independent prognostic indicator for survival of renal cancer patients. Silencing of ECRG4 expression in renal cell lines was associated with its promoter methylation. Moreover, ectopic expression of ECRG4 markedly inhibited cell proliferation and invasion in renal cancer cell lines. These results indicated that ECRG4 is frequently silenced by the methylation of promoter in renal cell cancers. ECRG4 may be a tumor suppressor in renal cancer and serve as a prognostic marker.

The EDA-containing cellular fibronectin induces epithelial-mesenchymal transition in lung cancer cells through integrin α9ß1-mediated activation of PI3-K/AKT and Erk1/2.

Cellular fibronectin (cFN) is one of the main components of tissue extracellular matrices and is involved in multiple physiologic and pathologic processes such as embryogenesis, wound healing, inflammation and tumor progression. The function of fibronectin in regulating normal cell adhesion and migration is well documented, but its function in cancer progression is only partially unraveled. We have reported previously that fibronectin stimulates the proliferation and survival of non-small lung carcinoma cells through upregulation of pro-oncogenic signals related to cyclooxygenase-2/phosphatidylinositol-3-kinase/protein kinase B (COX-2/PI3-K/AKT)/mammalian target of rapamycin triggered by activation of the integrin α5ß1. Here, we extend these studies by showing that fibronectin promotes epithelial-mesenchymal transition (EMT) in lung cancer cells. We found that cFN, but not plasma fibronectin or type 1 collagen, induces lung carcinoma cell scattering in vitro, promotes cell migration and invasion of Matrigel and stimulates the expression of the mesenchymal marker α-smooth muscle actin while decreasing the expression of the epithelial marker E-cadherin through PI3-K and Erk pathways. Interestingly, the extra domain A (EDA) within cFN was found to be crucial for this process, as confirmed by testing cells overexpressing EDA or cells exposed to EDA-containing matrices. We found that the integrin α9, but not α5, mediated cFN-induced EMT as silencing integrin α9 neutralized cFN-induced EMT. Overall, our findings show that the EDA domain within cFN induces EMT in lung carcinoma cells through integrin α9-mediated activation of PI3-K and Erk.

Multilayered molecular profiling supported the monoclonal origin of metastatic renal cell carcinoma.

Primary renal cell carcinomas (pRCCs) have a high degree of intratumoral heterogeneity and are composed of multiple distinct subclones. However, it remains largely unknown that whether metastatic renal cell carcinomas (mRCCs) also have startling intratumoral heterogeneity or whether development of mRCCs is due to early dissemination or late diagnosis. To decipher the evolution of mRCC, we analyzed the multilayered molecular profiles of pRCC, local invasion of the vena cava (IVC), and distant metastasis to the brain (MB) from the same patient using whole-genome sequencing, whole-exome sequencing, DNA methylome profiling, and transcriptome sequencing. We found that mRCC had a lower degree of heterogeneity than pRCC and was likely to result from recent clonal expansion of a rare, advantageous subclone. Consequently, some key pathways that are targeted by clinically available drugs showed distinct expression patterns between pRCC and mRCC. From the genetic distances between different tumor subclones, we estimated that the progeny subclone giving rise to distant metastasis took over half a decade to acquire the full potential of metastasis since the birth of the subclone that evolved into IVC. Our evidence supported that mRCC was monoclonal and distant metastasis occurred late during renal cancer progression. Thus, there was a broad window for early detection of circulating tumor cells and future targeted treatments for patients with mRCCs should rely on the molecular profiles of metastases.

An Alu element-mediated 28.5 kb α-thalassemia deletion found in a Chinese family.

Over 95.0% of the α-thalassemia (α-thal) cases in southern China are caused by large deletions involving the α-globin gene. Here, we describe the molecular characterization of a novel 28.5 kb deletion that eliminated one of the duplicated α-globin genes in a Chinese family. The deletion breakpoint fragment involved Alu repeat sequences, suggesting a homologous recombination event. Phenotypic analysis on the heterozygous carrier of this deletion revealed that it leads to a very mild phenotype. Because of a 25.0% risk of Hb H (ß4) disease in the offspring when in combination with another α(0)-thal allele, we should not ignore screening the deletion in prenatal diagnosis in order to decrease reproductive risk.

Computational identification of long non-coding RNAs associated with graphene therapy in glioblastoma multiforme.

Glioblastoma multiforme represents the most prevalent primary malignant brain tumour, while long non-coding RNA assumes a pivotal role in the pathogenesis and progression of glioblastoma multiforme. Nonetheless, the successful delivery of long non-coding RNA-based therapeutics to the tumour site has encountered significant obstacles attributable to inadequate biocompatibility and inefficient drug delivery systems. In this context, the use of a biofunctional surface modification of graphene oxide has emerged as a promising strategy to surmount these challenges. By changing the surface of graphene oxide, enhanced biocompatibility can be achieved, facilitating efficient transport of long non-coding RNA-based therapeutics specifically to the tumour site. This innovative approach presents the opportunity to exploit the therapeutic potential inherent in long non-coding RNA biology for treating glioblastoma multiforme patients. This study aimed to extract relevant genes from The Cancer Genome Atlas database and associate them with long non-coding RNAs to identify graphene therapy-related long non-coding RNA. We conducted a series of analyses to achieve this goal, including univariate Cox regression, least absolute shrinkage and selection operator regression and multivariate Cox regression. The resulting graphene therapy-related long non-coding RNAs were utilized to develop a risk score model. Subsequently, we conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses on the identified graphene therapy-related long non-coding RNAs. Additionally, we employed the risk model to construct the tumour microenvironment model and analyse drug sensitivity. To validate our findings, we referenced the IMvigor210 immunotherapy model. Finally, we investigated differences in the tumour stemness index. Through our investigation, we identified four promising graphene therapy-related long non-coding RNAs (AC011405.1, HOXC13-AS, LINC01127 and LINC01574) that could be utilized for treating glioblastoma multiforme patients. Furthermore, we identified 16 compounds that could be utilized in graphene therapy. Our study offers novel insights into the treatment of glioblastoma multiforme, and the identified graphene therapy-related long non-coding RNAs and compounds hold promise for further research in this field. Furthermore, additional biological experiments will be essential to validate the clinical significance of our model. These experiments can help confirm the potential therapeutic value and efficacy of the identified graphene therapy-related long non-coding RNAs and compounds in treating glioblastoma multiforme.

Advancements and applications of single-cell multi-omics techniques in cancer research: Unveiling heterogeneity and paving the way for precision therapeutics.

Single-cell multi-omics technologies have revolutionized cancer research by allowing us to examine individual cells at a molecular level. Unlike traditional bulk omics approaches, which analyze populations of cells together, single-cell multi-omics enables us to uncover the heterogeneity within tumors and understand the unique molecular characteristics of different cell populations. By doing so, we can identify rare subpopulations of cells that are influential in tumor growth, metastasis, and resistance to therapy. Moreover, single-cell multi-omics analysis provides valuable insights into the immune response triggered by various therapeutic interventions, such as immune checkpoint blockade, chemotherapy, and cell therapy. It also helps us better understand the intricate tumor microenvironment and its impact on patient prognosis and response to treatment. This comprehensive review focuses on the recent advancements in single-cell multi-omics methodologies, with an emphasis on single-cell multi-omics technologies. It highlights the important role of these techniques in uncovering the complexity of tumorigenesis and its multiple applications in cancer research, as well as their equally great contributions in other areas such as immunology. Through single-cell multi-omics, we gain a deeper understanding of cancer biology and pave the way for more precise and effective therapeutic strategies. Apart from those above, this paper also aims to introduce the advancements in live cell imaging technology, the latest developments in protein detection techniques, and explore their seamless integration with single-cell multi-omics technology.

A ferroptosis-related LncRNAs signature for predicting prognoses and screening potential therapeutic drugs in patients with lung adenocarcinoma: A retrospective study.

BACKGROUND: Lung adenocarcinoma (LUAD) has a high mortality rate. Ferroptosis is linked to tumor initiation and progression. AIMS: This study aims to develop prognostic models of ferroptosis-related lncRNAs, evaluate the correlation between differentially expressed genes and tumor microenvironment, and identify prospective drugs for managing LUAD. METHODS AND RESULTS: In this study, transcriptomic and clinical data were downloaded from the TCGA database, and ferroptosis-related genes were obtained from the FerrDb database. Through correlation analysis, Cox analysis, and the LASSO algorithm for constructing a prognostic model, we found that ferroptosis-related lncRNA-based gene signatures (FLncSig) had a strong prognostic predicting ability in the LUAD patients. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichments reconfirmed that ferroptosis is related to receptor-ligand activity, enzyme inhibitor activity, and the IL-17 signaling pathway. Next, tumor mutation burden (TMB), tumor immune dysfunction and exclusion (TIDE) algorithms, and pRRophetic were used to predict immunotherapy response and chemotherapy sensitivity. The IMvigor210 cohort was also used to validate the prognostic model. In the tumor microenvironment, Type_II_IFN_Response and HLA were found to be a group of low-risk pathways, while MHC_class_I was a group of high-risk pathways. Patients in the high-risk subgroup had lower TIDE scores. Exclusion, MDSC, CAF, and TAMM2 were significantly and positively correlated with risk scores. In addition, we found 15 potential therapeutic drugs for LUAD. Finally, differential analysis of stemness index based on mRNA expression (mRNAsi) indicated that mRNAsi was correlated with gender, primary tumor (T), distant metastasis (M), and the tumor, node, and metastasis (TNM) stage in LUAD patients. CONCLUSIONS: In conclusion, the prognostic model based on FLncSig can alleviate the difficulty in predicting the prognosis and immunotherapy of LUAD patients. The identified FLncSig and the screened drugs exhibit potential for clinical application and provide references for the treatment of LUAD.

TMEM52B Isoforms P18 and P20 Differentially Promote the Oncogenesis and Metastasis of Nasopharyngeal Carcinoma.

Transmembrane protein 52B (TMEM52B), a newly identified tumor-related gene, has been reported to regulate various tumors, yet its role in nasopharyngeal carcinoma (NPC) remains unclear. Transcriptomic analysis of NPC cell lines reveals frequent overexpression of TMEM52B, and immunohistochemical results show that TMEM52B is associated with advanced tumor stage, recurrence, and decreased survival time. Depleting TMEM52B inhibits the proliferation, migration, invasion, and oncogenesis of NPC cells in vivo. TMEM52B encodes two isoforms, TMEM52B-P18 and TMEM52B-P20, differing in their N-terminals. While both isoforms exhibit similar pro-oncogenic roles and contribute to drug resistance in NPC, TMEM52B-P20 differentially promotes metastasis. This functional discrepancy may be attributed to their distinct subcellular localization; TMEM52B-P18 is confined to the cytoplasm, while TMEM52B-P20 is found both at the cell membrane and in the cytoplasm. Mechanistically, cytoplasmic TMEM52B enhances AKT phosphorylation by interacting with phosphoglycerate kinase 1 (PGK1), fostering NPC growth and metastasis. Meanwhile, membrane-localized TMEM52B-P20 promotes E-cadherin ubiquitination and degradation by facilitating its interaction with the E3 ubiquitin ligase NEDD4, further driving NPC metastasis. In conclusion, the TMEM52B-P18 and TMEM52B-P20 isoforms promote the metastasis of NPC cells through different mechanisms. Drugs targeting these TMEM52B isoforms may offer therapeutic benefits to cancer patients with varying degrees of metastasis.

Role of PCDH10 and its hypermethylation in human gastric cancer.

Epigenetic changes of genomic DNA are involved in the development and progression of many cancers. Aberrant methylation of CpG islands in the promoter regions of certain tumor-suppressor genes (TSG) is frequently observed in cancer cells. Protocadherin 10 (PCDH10), a member of the cadherin superfamily, is a recently identified putative TSG. PCDH10 is frequently silenced in many solid tumors. However, the role of PCDH10 in gastric cancer is largely unknown. In this study, we examined the expression and methylation status of PCDH10 in gastric cancer cells and tissues by real time PCR and methylation-specific PCR (MSP), and then investigated the biological function of PCDH10. We found that the expression of PCDH10 was markedly reduced in gastric cancer cells and tissues. The reduced expression correlated with hypermethylation of this gene in its promoter region, as demonstrated by MSP and bisulfite genomic sequencing (BGS) analysis. In addition, pharmacological demethylation using 5-Aza restored the expression of PCDH10 in gastric cancer cells. Over-expression of PCDH10 in gastric cancer cells suppressed cell proliferation and migration, but did not cause marked apoptosis. Over-expression of PCDH10 also suppressed growth of xenograft tumors in nude mice. Thus, PCDH10 functions as a TSG in gastric cancer, and might be a useful target for cancer therapy.

A dominant-negative mutation of HSF2 associated with idiopathic azoospermia.

Idiopathic azoospermia (IA) is a severe form of male infertility due to unknown causes. The HSF2 gene, encoding the heat shock transcription factor 2, had been suggested to play a significant role in the spermatogenesis process since the Hsf2-knockout male mice showed spermatogenesis defects. To examine whether HSF2 is involved in the pathogenesis of IA in human, we sequenced all the exons of HSF2 in 766 patients diagnosed with IA and 521 proven fertile men. A number of coding mutations private to the patient group, which include three synonymous mutations and five missense mutations, were identified. Of the missense mutations, our functional assay demonstrated that one heterozygous mutation, R502H, caused a complete loss of HSF2 function and that the mutant suppressed the normal function of the wild-type (WT) allele through a dominant-negative effect, thus leading to the dominant penetrance of the mutant allele. These results support a role for HSF2 in the pathogenesis of IA and further implicate this transcription factor as a potential therapeutic target.