Identifying SLC2A6 as the novel protective factor in breast cancer by TP53-related genes affecting M1 macrophage infiltration.

The high heterogeneity of breast cancer (BC) caused by pathogenic gene mutations poses a challenge to immunotherapy, but the underlying mechanism remains unknown. The difference in the infiltration of M1 macrophages induced by TP53 mutations has a significant impact on BC immunotherapy. The aim of this study was to develop a TP53-related M1 macrophage infiltration molecular typing risk signature in BC and evaluate the biological functions of the key gene to find new immunotherapy biomarkers. Weighted correlation network analysis (WGCNA) and negative matrix factorization (NMF) were used for distinguishing BC subtypes. The signature and the nomogram were both constructed and evaluated. Biological functions of the novel signature gene SLC2A6 were confirmed through in vitro and in vivo experiments. RNA-Sequencing and protein profiling were used for detecting the possible mechanism of SLC2A6. The results suggested that four BC subtypes were distinguished by TP53-related genes that affect M1 macrophage infiltration. The signature constructed by molecular typing characteristics could evaluate BC's clinical features and tumor microenvironment. The nomogram could accurately predict the prognosis. The signature gene SLC2A6 was found to have an abnormally low expression in tumor tissues. Overexpression of SLC2A6 could inhibit proliferation, promote mitochondrial damage, and result in apoptosis of tumor cells. The HSP70 family member protein HSPA6 could bind with SLC2A6 and increase with the increased expression of SLC2A6. In summary, the risk signature provides a reference for BC risk assessment, and the signature gene SLC2A6 could act as a tumor suppressor in BC.

Comprehensive analysis of KLF family reveals KLF6 as a promising prognostic and immune biomarker in pancreatic ductal adenocarcinoma.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest tumors worldwide, with extremely aggressive and complicated biology. Krüppel-like factors (KLFs) encode a series of transcriptional regulatory proteins and play crucial roles in a variety of processes, including tumor cell differentiation and proliferation. However, the potential biological functions and possible pathways of KLFs in the progression of PDAC remain elusive. METHODS: We systematically evaluated the transcriptional variations and expression patterns of KLFs in pancreatic cancer from the UCSC Xena. Based on difference analysis, the non-negative matrix factorization (NMF) algorithm was utilized to identify the immune characteristics and clinical significance of two different subtypes. The multivariate Cox regression was used to construct the risk model and then explore the differences in tumor immune microenvironment (TIME) and drug sensitivity between high and low groups. Through single-cell RNA sequencing (scRNA-seq) analysis, we screened KLF6 and further investigated its biological functions in pancreatic cancer and pan-cancer. RESULTS: The KLFs exhibited differential expression and mutations in the transcriptomic profile of PDAC. According to the expression of KLFs, patients were classified into two distinct subtypes, each exhibiting significant differences in prognosis and TIME. Moreover, the KLF signature was developed using univariate Cox and Lasso regression, which proved to be a reliable and effective prognostic model. Furthermore, the KLF_Score was closely associated with immune infiltration, response to immunotherapy, and drug sensitivity and we screened small molecule compounds targeting prognostic genes separately. Through scRNA-seq analysis, KLF6 was selected to further demonstrate its role in the malignance of PC in vitro. Finally, pan-cancer analysis emphasized the biological significance of KLF6 in multiple types of tumors and its clinical utility in assessing cancer prognosis. CONCLUSION: This study elucidated the pivotal role of KLF family genes in the malignant development of PC through comprehensive analysis and revealed that KLF6 would be a novel diagnostic biomolecule marker and potential therapeutic target for PDAC.

Single-cell RNA-seq analysis reveals BHLHE40-driven pro-tumour neutrophils with hyperactivated glycolysis in pancreatic tumour microenvironment.

OBJECTIVE: Innate immunity plays important roles in pancreatic ductal adenocarcinoma (PDAC), as non-T-cell-enriched tumour. Neutrophils are major players in innate immune system. Here, we aimed to explore the heterogeneity and pro-tumour mechanisms of neutrophils in PDAC. DESIGN: We analysed single-cell transcriptomes of peripheral blood polymorphonuclear leucocytes (PMNs) and tumour-infiltrating immune cells from five patients with PDAC, and performed immunofluorescence/immunohistochemistry staining, multi-omics analysis and in vitro experiments to validate the discoveries of bioinformatics analysis. RESULTS: Exploration of the heterogeneity of tumour-associated neutrophils (TANs) revealed a terminally differentiated pro-tumour subpopulation (TAN-1) associated with poor prognosis, an inflammatory subpopulation (TAN-2), a population of transitional stage that have just migrated to tumour microenvironment (TAN-3) and a subpopulation preferentially expressing interferon-stimulated genes (TAN-4). Glycolysis signature was upregulated along neutrophil transition trajectory, and TAN-1 was featured with hyperactivated glycolytic activity. The glycolytic switch of TANs was validated by integrative multi-omics approach of transcriptomics, proteomics and metabolomics analysis. Activation of glycolytic activity by LDHA overexpression induced immunosuppression and pro-tumour functions in neutrophil-like differentiated HL-60 (dHL-60) cells. Mechanistic studies revealed BHLHE40, downstream to hypoxia and endoplasmic reticulum stress, was a key regulator in polarisation of neutrophils towards TAN-1 phenotype, and direct transcriptional regulation of BHLHE40 on TAN-1 marker genes was demonstrated by chromatin immunoprecipitation assay. Pro-tumour and immunosuppression functions were observed in dHL-60 cells overexpressing BHLHE40. Importantly, immunohistochemistry analysis of PDAC tissues revealed the unfavourable prognostic value of BHLHE40+ neutrophils. CONCLUSION: The dynamic properties of TANs revealed by this study will be helpful in advancing PDAC therapy targeting innate immunity.

Identification of a novel immune checkpoint molecule V-set immunoglobulin domain-containing 4 that leads to impaired immunity infiltration in pancreatic ductal adenocarcinoma.

BACKGROUND: Checkpoint-based immunotherapy has failed to elicit responses in the majority of patients with pancreatic cancer. In our study, we aimed to identify the role of a novel immune checkpoint molecule V-set Ig domain-containing 4 (VSIG4) in pancreatic ductal adenocarcinoma (PDAC). METHODS: Online datasets and tissue microarray (TMA) were utilized to analyze the expression level of VSIG4 and its correlation with clinical parameters in PDAC. CCK8, transwell assay and wound healing assay were applied to explore the function of VSIG4 in vitro. Subcutaneous, orthotopic xenograft and liver metastasis model was established to explore the function of VSIG4 in vivo. TMA analysis and chemotaxis assay were conducted to uncover the effect of VSIG4 on immune infiltration. Histone acetyltransferase (HAT) inhibitors and si-RNA were applied to investigate factors that regulate the expression of VSIG4. RESULTS: Both mRNA and protein levels of VSIG4 were higher in PDAC than normal pancreas in TCGA, GEO, HPA datasets and our TMA. VSIG4 showed positive correlations with tumor size, T classification and liver metastasis. Patients with higher VSIG4 expression were related to poorer prognosis. VSIG4 knockdown impaired the proliferation and migration ability of pancreatic cancer cells both in vitro and in vivo. Bioinformatics study showed positive correlation between VSIG4 and infiltration of neutrophil and tumor-associated macrophages (TAMs) in PDAC, and it inhibited the secretion of cytokines. According to our TMA panel, high expression of VSIG4 was correlated with fewer infiltration of CD8+ T cells. Chemotaxis assay also showed knockdown of VSIG4 increased the recruitment of total T cells and CD8+ T cells. HAT inhibitors and knockdown of STAT1 led to decreased expression of VSIG4. CONCLUSIONS: Our data indicate that VSIG4 contributes to cell proliferation, migration and resistance to immune attack, thus identified as a promising target for PDAC treatment with good prognostic value.

LIPH contributes to glycolytic phenotype in pancreatic ductal adenocarcinoma by activating LPA/LPAR axis and maintaining ALDOA stability.

BACKGROUND: LIPH, a membrane-associated phosphatidic acid-selective phospholipase A1a, can produce LPA (Lysophosphatidic acid) from PA (Phosphatidic acid) on the outer leaflet of the plasma membrane. It is well known that LIPH dysfunction contributes to lipid metabolism disorder. Previous study shows that LIPH was found to be a potential gene related to poor prognosis with pancreatic ductal adenocarcinoma (PDAC). However, the biological functions of LIPH in PDAC remain unclear. METHODS: Cell viability assays were used to evaluate whether LIPH affected cell proliferation. RNA sequencing and immunoprecipitation showed that LIPH participates in tumor glycolysis by stimulating LPA/LPAR axis and maintaining aldolase A (ALDOA) stability in the cytosol. Subcutaneous, orthotopic xenograft models and patient-derived xenograft PDAC model were used to evaluate a newly developed Gemcitabine-based therapy. RESULTS: LIPH was significantly upregulated in PDAC and was related to later pathological stage and poor prognosis. LIPH downregulation in PDAC cells inhibited colony formation and proliferation. Mechanistically, LIPH triggered PI3K/AKT/HIF1A signaling via LPA/LPAR axis. LIPH also promoted glycolysis and de novo synthesis of glycerolipids by maintaining ALDOA stability in the cytosol. Xenograft models show that PDAC with high LIPH expression levels was sensitive to gemcitabine/ki16425/aldometanib therapy without causing discernible side effects. CONCLUSION: LIPH directly bridges PDAC cells and tumor microenvironment to facilitate aberrant aerobic glycolysis via activating LPA/LPAR axis and maintaining ALDOA stability, which provides an actionable gemcitabine-based combination therapy with limited side effects.

Exosomal hsa-let-7g-3p and hsa-miR-10395-3p derived from peritoneal lavage predict peritoneal metastasis and the efficacy of neoadjuvant intraperitoneal and systemic chemotherapy in patients with gastric cancer.

BACKGROUND: The prognosis of advanced gastric cancer (GC) invading the gastric serosa remains poor, mainly owing to high incidence of peritoneal recurrence. Patients with peritoneal metastases are often treated with neoadjuvant intraperitoneal and systemic chemotherapies (NIPS). Good responders to NIPS often undergo conversion gastrectomy. This study aims to explore biomarkers predicting the occurrence of peritoneal metastasis (PM) and evaluating the efficacy of NIPS in GC patients. METHODS: We collected six peritoneal lavage (PL) samples from two patients with PM, two without PM, and two with diminished PM after NIPS via intraperitoneal access ports. We equally isolated microRNAs from exosomes derived from PL samples for deep sequencing. Two microRNAs (hsa-let-7g-3p and hsa-miR-10395-3p) were identified, and their expression levels were examined in PL samples of 99 GC patients using qRT-PCR. Moreover, we performed in vivo and in vitro functional assays to investigate effects of these microRNAs on metastasis and chemoresistance of GC cells. RESULTS: Exosomal microRNA expression profiling of six PL samples indicated that the microRNA signature in exosomes of PLs from patients with diminished PM was similar to that from patients without PM. Expression levels of hsa-let-7g-3p and hsa-miR-10395-3p were associated with PM. In vivo and in vitro functional assays confirmed that hsa-let-7g-3p and hsa-miR-10395-3p are involved in GC metastasis and chemoresistance. CONCLUSION: PL-derived exosomes in GC contain large amounts of microRNAs related to PM. Moreover, hsa-let-7g-3p and hsa-miR-10395-3p could be used as biomarkers predicting PM and NIPS efficacy and are involved in GC metastasis and chemoresistance.

A hepatocyte differentiation model reveals two subtypes of liver cancer with different oncofetal properties and therapeutic targets.

Clinical observation of the association between cancer aggressiveness and embryonic development stage implies the importance of developmental signals in cancer initiation and therapeutic resistance. However, the dynamic gene expression during organogenesis and the master oncofetal drivers are still unclear, which impeded the efficient elimination of poor prognostic tumors, including human hepatocellular carcinoma (HCC). In this study, human embryonic stem cells were induced to differentiate into adult hepatocytes along hepatic lineages to mimic liver development in vitro. Combining transcriptomic data from liver cancer patients with the hepatocyte differentiation model, the active genes derived from different hepatic developmental stages and the tumor tissues were selected. Bioinformatic analysis followed by experimental assays was used to validate the tumor subtype-specific oncofetal signatures and potential therapeutic values. Hierarchical clustering analysis revealed the existence of two subtypes of liver cancer with different oncofetal properties. The gene signatures and their clinical significance were further validated in an independent clinical cohort and The Cancer Genome Atlas database. Upstream activator analysis and functional screening further identified E2F1 and SMAD3 as master transcriptional regulators. Small-molecule inhibitors specifically targeting the oncofetal drivers extensively down-regulated subtype-specific developmental signaling and inhibited tumorigenicity. Liver cancer cells and primary HCC tumors with different oncofetal properties also showed selective vulnerability to their specific inhibitors. Further precise targeting of the tumor initiating steps and driving events according to subtype-specific biomarkers might eliminate tumor progression and provide novel therapeutic strategy.

Nanotechnology Lighting the Way for Gene Therapy in Ophthalmopathy: From Opportunities toward Applications.

Hereditary ophthalmopathy is a well-described threat to human visual health affecting millions of people. Gene therapy for ophthalmopathy has received widespread attention with the increasing understanding of pathogenic genes. Effective and safe delivery of accurate nucleic acid drugs (NADs) is the core of gene therapy. Efficient nanodelivery and nanomodification technologies, appropriate targeted genes, and the choice of drug injection methods are the guiding lights of gene therapy. Compared with traditional drugs, NADs can specifically change the expression of specific genes or restore the normal function of mutant genes. Nanodelivery carriers can improve targeting and nanomodification can improve the stability of NADs. Therefore, NADs, which can fundamentally solve pathogeny, hold great promise in the treatment of ophthalmopathy. This paper reviews the limitations of ocular disease treatment, discusses the classification of NADs in ophthalmology, reveals the delivery strategies of NADs to improve bioavailability, targeting, and stability, and summarizes the mechanisms of NADs in ophthalmopathy.

Genetic landscape of FOXC2 mutations in lymphedema-distichiasis syndrome: Different mechanism of pathogenicity for mutations in different domains.

Lymphedema-dissociated syndrome (LDS), of which the pathogenesis is not fully understood, afflicts many patients. In this study, we investigated the effect of FOXC2 gene loss-of-function on the development of LDS disease. Two Han Chinese families with LDS were recruited in this study, pathogenic mutations were identified by Sanger sequencing. Reverse-transcription PCR, subcellular localization, dual fluorescein enzymes, and other in vitro experiments were used to study the functional effects of eight FOXC2 mutations. Two pathogenic FOXC2 duplication mutations (c.930_936dup and c.931-937dup) were identified in the two families. Both mutations caused uneven distribution in the nucleus and a chromatin contraction phenotype, weakening the DNA binding activity and transcription activity. We then performed functional analysis on six additional mutations in different domains of FOXC2 that were reported to cause LDS. We found mutations located in the forkhead domain and central region dramatically reduced the transactivation ability, while mutations in activation domain-2 enhanced this ability. All 8 mutations down-regulated the transcription of ANGPT2 and affected the activity of the ERK-RAS pathway, which may cause abnormal formation of lymphatic vessels. Our findings also showed that all 8 mutations decreased the ability of interaction between FOXC2 and the Wnt4 promoter, suggesting mutations in FOXC2 may also affect the Wnt4-Frizzled-RYK signaling pathway, leading the abnormal differentiation of the meibomian glands into hair follicle cells during the embryonic period and causing distichiasis. This study expanded and revealed the potential pathogenesis mechanism.

Development and validation of a cancer stem cell-related signature for prognostic prediction in pancreatic ductal adenocarcinoma.

BACKGROUND: Cancer stem cells (CSCs) are crucial to the malignant behaviour and poor prognosis of pancreatic ductal adenocarcinoma (PDAC). In recent years, CSC biology has been widely studied, but practical prognostic signatures based on CSC-related genes have not been established or reported in PDAC. METHODS: A signature was developed and validated in seven independent PDAC datasets. The MTAB-6134 cohort was used as the training set, while one local Chinese cohort and five other public cohorts were used for external validation. CSC-related genes with credible prognostic roles were selected to form the signature, and their predictive performance was evaluated by Kaplan-Meier survival, receiver operating characteristic (ROC), and calibration curves. Correlation analysis was employed to clarify the potential biological characteristics of the gene signature. RESULTS: A robust signature comprising DCBLD2, GSDMD, PMAIP1, and PLOD2 was developed. It classified patients into high-risk and low-risk groups. High-risk patients had significantly shorter overall survival (OS) and disease-free survival (DFS) than low-risk patients. Calibration curves and Cox regression analysis demonstrated powerful predictive performance. ROC curves showed the better survival prediction by this model than other models. Functional analysis revealed a positive association between risk score and CSC markers. These results had cross-dataset compatibility. Impact This signature could help further improve the current TNM staging system and provide data for the development of novel personalized therapeutic strategies in the future.

Calcium-binding protein 39 promotes hepatocellular carcinoma growth and metastasis by activating extracellular signal-regulated kinase signaling pathway.

Calcium-binding protein (CAB39) is a key regulator of a group of sterile 20 kinases. Here, we report that CAB39 was frequently up-regulated in hepatocellular carcinoma (HCC), which was significantly associated with tumor metastasis (P = 0.000), poorer disease-free survival rate (P = 0.027), and poor prognosis (P = 0.000). Ectopic expression of CAB39 in immortalized human liver cell line LO2 and HCC cell lines QGY-7703 and BEL-7402 could increase foci formation, colony formation in soft agar, tumor formation in nude mice, and cell motility. Silencing CAB39 expression in two HCC cell lines, Huh7 and MHCC97H, with short hairpin RNA could effectively abolish its oncogenic function. Further study found that CAB39 contributed to extracellular signal-regulated kinase (ERK) pathway activation, and mutations of the key sites of CAB39 markedly decrease the level of phosphorylated ERK. In addition, CAB39 could promote epithelial-mesenchymal transition by up-regulating N-cadherin and Fibronectin and down-regulating E-cadherin and α-E-catenin. As a result, ß-catenin nuclear translocation was increased and its downstream target gene, matrix metalloproteinase-9, was up-regulated. CONCLUSION: Taken together, our findings suggested that CAB39 played very important oncogenic roles in HCC pathogenesis and progression by activating the ERK signaling pathway. Better understanding of CAB39 may lead to its clinical application as a biomarker for a prognosis predictor and a novel therapeutic target. (Hepatology 2017;66:1529-1545).

CHD1L promotes lineage reversion of hepatocellular carcinoma through opening chromatin for key developmental transcription factors.

UNLABELLED: High-grade tumors with poor differentiation usually show phenotypic resemblance to their developmental ancestral cells. Cancer cells that gain lineage precursor cell properties usually hijack developmental signaling pathways to promote tumor malignant progression. However, the molecular mechanisms underlying this process remain unclear. In this study, the chromatin remodeler chromodomain-helicase-DNA-binding-protein 1-like (CHD1L) was found closely associated with liver development and hepatocellular carcinoma (HCC) tumor differentiation. Expression of CHD1L decreased during hepatocyte maturation and increased progressively from well-differentiated HCCs to poorly differentiated HCCs. Chromatin immunoprecipitation followed by high-throughput deep sequencing found that CHD1L could bind to the genomic sequences of genes related to development. Bioinformatics-aided network analysis indicated that CHD1L-binding targets might form networks associated with developmental transcription factor activation and histone modification. Overexpression of CHD1L conferred ancestral precursor-like properties of HCC cells both in vitro and in vivo. Inhibition of CHD1L reversed tumor differentiation and sensitized HCC cells to sorafenib treatment. Mechanism studies revealed that overexpression of CHD1L could maintain an active "open chromatin" configuration at promoter regions of estrogen-related receptor-beta and transcription factor 4, both of which are important regulators of HCC self-renewal and differentiation. In addition, we found a significant correlation of CHD1L with developmental transcriptional factors and lineage differentiation markers in clinical HCC patients. CONCLUSION: Genomic amplification of chromatin remodeler CHD1L might drive dedifferentiation of HCC toward an ancestral lineage through opening chromatin for key developmental transcriptional factors; further inhibition of CHD1L might "downgrade" poorly differentiated HCCs and provide novel therapeutic strategies.

HBP21, a chaperone of heat shock protein 70, functions as a tumor suppressor in hepatocellular carcinoma.

Inactivation of tumor suppressor genes, caused by genetic and epigenetic alterations, is one of the key issues in the development and progression of cancer. To identify and characterize cancer related genes in hepatocellular carcinoma (HCC) pathogenesis, transcriptome sequencing has been applied to compare expression profiles between tumor and non-tumor tissues. Among the down-regulated genes, heat shock binding protein 21 (HBP21) was selected for further study. In this study, down-regulation of HBP21 was frequently detected in primary HCCs (87/120, 72.5%), which was significantly associated with advanced clinical stage (P = 0.049), poor differentiation (P = 0.018) and poor prognosis (P = 0.026). Further study found that down-regulation of HBP21 in HCC was mainly caused by allele loss and promoter methylation. Functional study found that HBP21 could inhibit tumor cell growth rate, foci formation and colony formation in soft agar, and tumor formation in nude mice when it was transfected into HCC cells. Molecular study found that HBP21 could promote cell apoptosis, especially under adverse conditions such as heat and chemotherapeutic agent treatment. As a chaperone of heat shock protein 70 (HSP70), HBP21 could inhibit interaction between HSP70 and Bax, increased Bax protein translocation from cytoplasm to mitochondria, and subsequently increased the release of cytochrome c into cytoplasm, and finally induced apoptosis. Clinically, HBP21 could be used as a prognostic biomarker for HCC outcome prediction and might be also as a novel therapeutic agent in HCC treatment.

Identification and validation of a novel six-gene signature based on mucinous adenocarcinoma-related gene molecular typing in colorectal cancer.

BACKGROUND AND OBJECTIVES: Colorectal mucinous adenocarcinoma (MAC) is a particular pathological type that has yet to be thoroughly studied. This study aims to investigate the characteristics of colorectal MAC-related genes in colorectal cancer (CRC), explore the role of MAC-related genes in accurately classifying CRC, and further construct a prognostic signature. METHODS: CRC samples were collected from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). MAC-related differentially expressed genes (DEGs) were analyzed in TCGA samples. Based on colorectal MAC-related genes, TCGA CRC samples were molecularly typed by the non-negative matrix factorization (NMF). According to the molecular subtype characteristics, the RiskScore signature was constructed through univariate Cox, the least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression analyses. Clinical significance in CRC of the RiskScore signature was analyzed. A nomogram was further built based on the RiskScore signature. RESULTS: From the colorectal MAC-related genes, three distinct molecular subtypes were identified. A RiskScore signature composed of six CRC subtype-related genes (CALB1, MMP1, HOXC6, ZIC2, SFTA2, and HYAL1) was constructed. Patients with high-RiskScores had the worse prognoses. RiskScores led to differences in gene mutation characteristics, antitumor drug sensitivity, and tumor microenvironment of CRC. A nomogram based on the signature was developed to predict the one-, three-, and five-year survival of CRC patients. CONCLUSION: MAC-related genes were able to classify CRC. A RiskScore signature based on the colorectal MAC-related molecular subtype was constructed, which had important clinical significance for guiding the accurate stratification of CRC patients.

Identification of LRRC46 as a novel candidate gene for high myopia.

High myopia (HM) is the primary cause of blindness, with the microstructural organization and composition of collagenous fibers in the cornea and sclera playing a crucial role in the biomechanical behavior of these tissues. In a previously reported myopic linkage region, MYP5 (17q21-22), a potential candidate gene, LRRC46 (c.C235T, p.Q79X), was identified in a large Han Chinese pedigree. LRRC46 is expressed in various eye tissues in humans and mice, including the retina, cornea, and sclera. In subsequent cell experiments, the mutation (c.C235T) decreased the expression of LRRC46 protein in human corneal epithelial cells (HCE-T). Further investigation revealed that Lrrc46-/- mice (KO) exhibited a classical myopia phenotype. The thickness of the cornea and sclera in KO mice became thinner and more pronounced with age, the activity of limbal stem cells decreased, and microstructural changes were observed in the fibroblasts of the sclera and cornea. We performed RNA-seq on scleral and corneal tissues of KO and normal control wild-type (WT) mice, which indicated a significant downregulation of the collagen synthesis-related pathway (extracellular matrix, ECM) in KO mice. Subsequent in vitro studies further indicated that LRRC46, a member of the important LRR protein family, primarily affected the formation of collagens. This study suggested that LRRC46 is a novel candidate gene for HM, influencing collagen protein VIII (Col8a1) formation in the eye and gradually altering the biomechanical structure of the cornea and sclera, thereby promoting the occurrence and development of HM.

BHLHE40 Inhibits Ferroptosis in Pancreatic Cancer Cells via Upregulating SREBF1.

Pancreatic cancer (PCa) is one of the most fatal human malignancies. The enhanced infiltration of stromal tissue into the PCa tumor microenvironment limits the identification of key tumor-specific transcription factors and epigenomic abnormalities in malignant epithelial cells. Integrated transcriptome and epigenetic multiomics analyses of the paired PCa organoids indicate that the basic helix-loop-helix transcription factor 40 (BHLHE40) is significantly upregulated in tumor samples. Increased chromatin accessibility at the promoter region and enhanced mTOR pathway activity contribute to the elevated expression of BHLHE40. Integrated analysis of chromatin immunoprecipitation-seq, RNA-seq, and high-throughput chromosome conformation capture data, together with chromosome conformation capture assays, indicate that BHLHE40 not only regulates sterol regulatory element-binding factor 1 (SREBF1) transcription as a classic transcription factor but also links the enhancer and promoter regions of SREBF1. It is found that the BHLHE40-SREBF1-stearoyl-CoA desaturase axis protects PCa cells from ferroptosis, resulting in the reduced accumulation of lipid peroxidation. Moreover, fatostatin, an SREBF1 inhibitor, significantly suppresses the growth of PCa tumors with high expressions of BHLHE40. This study highlights the important roles of BHLHE40-mediated lipid peroxidation in inducing ferroptosis in PCa cells and provides a novel mechanism underlying SREBF1 overexpression in PCa.

Deterministic reprogramming of neutrophils within tumors.

Neutrophils are increasingly recognized as key players in the tumor immune response and are associated with poor clinical outcomes. Despite recent advances characterizing the diversity of neutrophil states in cancer, common trajectories and mechanisms governing the ontogeny and relationship between these neutrophil states remain undefined. Here, we demonstrate that immature and mature neutrophils that enter tumors undergo irreversible epigenetic, transcriptional, and proteomic modifications to converge into a distinct, terminally differentiated dcTRAIL-R1+ state. Reprogrammed dcTRAIL-R1+ neutrophils predominantly localize to a glycolytic and hypoxic niche at the tumor core and exert pro-angiogenic function that favors tumor growth. We found similar trajectories in neutrophils across multiple tumor types and in humans, suggesting that targeting this program may provide a means of enhancing certain cancer immunotherapies.

Prospective observational study on biomarkers of response in pancreatic ductal adenocarcinoma.

Adjuvant chemotherapy benefits patients with resected pancreatic ductal adenocarcinoma (PDAC), but the compromised physical state of post-operative patients can hinder compliance. Biomarkers that identify candidates for prompt adjuvant therapy are needed. In this prospective observational study, 1,171 patients with PDAC who underwent pancreatectomy were enrolled and extensively followed-up. Proteomic profiling of 191 patient samples unveiled clinically relevant functional protein modules. A proteomics-level prognostic risk model was established for PDAC, with its utility further validated using a publicly available external cohort. More importantly, through an interaction effect regression analysis leveraging both clinical and proteomic datasets, we discovered two biomarkers (NDUFB8 and CEMIP2), indicative of the overall sensitivity of patients with PDAC to adjuvant chemotherapy. The biomarkers were validated through immunohistochemistry on an internal cohort of 386 patients. Rigorous validation extended to two external multicentic cohorts-a French multicentric cohort (230 patients) and a cohort from two grade-A tertiary hospitals in China (466 patients)-enhancing the robustness and generalizability of our findings. Moreover, experimental validation through functional assays was conducted on PDAC cell lines and patient-derived organoids. In summary, our cohort-scale integration of clinical and proteomic data demonstrates the potential of proteomics-guided prognosis and biomarker-aided adjuvant chemotherapy for PDAC.

A novel PD-1/PD-L1 pathway molecular typing-related signature for predicting prognosis and the tumor microenvironment in breast cancer.

BACKGROUND: Currently, the development of breast cancer immunotherapy based on the PD-1/PD-L1 pathway is relatively slow, and the specific mechanism affecting the immunotherapy efficacy in breast cancer is still unclear. METHODS: Weighted correlation network analysis (WGCNA) and the negative matrix factorization (NMF) were used to distinguish subtypes related to the PD-1/PD-L1 pathway in breast cancer. Then univariate Cox, least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression were used to construct the prognostic signature. A nomogram was established based on the signature. The relationship between the signature gene IFNG and breast cancer tumor microenvironment was analyzed. RESULTS: Four PD-1/PD-L1 pathway-related subtypes were distinguished. A prognostic signature related to PD-1/PD-L1 pathway typing was constructed to evaluate breast cancer's clinical characteristics and tumor microenvironment. The nomogram based on the RiskScore could be used to accurately predict breast cancer patients' 1-year, 3-year, and 5-year survival probability. The expression of IFNG was positively correlated with CD8+ T cell infiltration in the breast cancer tumor microenvironment. CONCLUSION: A prognostic signature is constructed based on the PD-1/PD-L1 pathway typing in breast cancer, which can guide the precise treatment of breast cancer. The signature gene IFNG is positively related to CD8+ T cell infiltration in breast cancer.

A Novel Pair of Compound Heterozygous Mutation of EYS in a Han Chinese Family with Retinitis Pigmentosa.

Background: Retinitis pigmentosa (RP) is a complex inherited and progressive degenerative retinal disease. The eyes shut homolog (EYS) is frequently associated with RP is surprisingly high. Exploring the function of EYS is quite difficult due to the unique gene size and species specificity. Gene therapy may provide a breakthrough to treat this disease. Therefore, exploring and clarifying pathogenic mutations of EYS-associated RP has important guiding significance for clinical treatment. Methods: Clinical and molecular genetic data for EYS-associated RP were retrospectively analyzed. Sanger sequencing was applied to identify novel mutations in these patients. Candidate pathogenic variants were subsequently evaluated using bioinformatic tools. Results: A novel pair of compound heterozygous mutations was identified: a novel stop-gain mutation c.2439C>A (p.C813fsX) and a frameshift deletion mutation c.6714delT (p. P2238fsX) of the EYS gene in the RP family. Both of these mutations were rare or absent in the 1000 Genomes Project, dbSNP, and Genome Aggregation Database (gnomAD). These two mutations would result in a lack of multiple functionally important epidermal growth factor-like and Laminin G-like coding regions in EYS. Conclusions: A novel compound heterozygote of the EYS gene in a Chinese family with an autosomal inheritance pattern of RP was identified. Identifying more pathogenic mutations and expanding the mutation spectrum of the EYS gene will contribute to a more comprehensive understanding of the molecular pathogenesis of RP disease that could be gained in the future. It also could provide an important basis for the diagnosis, clinical management, and genetic counseling of the disease.