PSMA5 promotes the tumorigenic process of prostate cancer and is related to bortezomib resistance

Integration of single-cell sequencing and bulk RNA-seq to identify and develop a prognostic signature related to colorectal cancer stem cells

The prognosis for patients with colorectal cancer (CRC) remains worse than expected due to metastasis, recurrence, and resistance to chemotherapy. Colorectal cancer stem cells (CRCSCs) play a vital role in tumor metastasis, recurrence, and chemotherapy resistance. However, there are currently no prognostic markers based on CRCSCs-related genes available for clinical use. In this study, single-cell transcriptome sequencing was employed to distinguish cancer stem cells (CSCs) in the CRC microenvironment and analyze their properties at the single-cell level. Subsequently, data from TCGA and GEO databases were utilized to develop a prognostic risk model for CRCSCs-related genes and validate its diagnostic performance. Additionally, functional enrichment, immune response, and chemotherapeutic drug sensitivity of the relevant genes in the risk model were investigated. Lastly, the key gene RPS17 in the risk model was identified as a potential prognostic marker and therapeutic target for further comprehensive studies. Our findings provide new insights into the prognostic treatment of CRC and offer novel perspectives for a systematic and comprehensive understanding of CRC development.

Machine learning developed a CD8+ exhausted T cells signature for predicting prognosis, immune infiltration and drug sensitivity in ovarian cancer

CD8+ exhausted T cells (CD8+ Tex) played a vital role in the progression and therapeutic response of cancer. However, few studies have fully clarified the characters of CD8+ Tex related genes in ovarian cancer (OC). The CD8+ Tex related prognostic signature (TRPS) was constructed with integrative machine learning procedure including 10 methods using TCGA, GSE14764, GSE26193, GSE26712, GSE63885 and GSE140082 dataset. Several immunotherapy benefits indicators, including Tumor Immune Dysfunction and Exclusion (TIDE) score, immunophenoscore (IPS), TMB score and tumor escape score, were used to explore performance of TRPS in predicting immunotherapy benefits of OC. The TRPS constructed by Enet (alpha = 0.3) method acted as an independent risk factor for OC and showed stable and powerful performance in predicting clinical outcome of patients. The C-index of the TRPS was higher than that of tumor grade, clinical stage, and many developed signatures. Low TRPS score indicated a higher level of CD8+ T cell, B cell, macrophage M1, and NK cells, representing a relative immunoactivated ecosystem in OC. OC patients with low risk score had a higher PD1&CTLA4 immunophenoscore, higher TMB score, lower TIDE score and lower tumor escape score, suggesting a better immunotherapy response. Moreover, higher TRPS score indicated a higher score of cancer-related hallmarks, including angiogenesis, EMT, hypoxia, glycolysis, and notch signaling. Vitro experiment showed that ARL6IP5 was downregulated in OC tissues and inhibited tumor cell proliferation. The current study constructed a novel TRPS for OC, which could serve as an indicator for predicting the prognosis, immune infiltration and immunotherapy benefits for OC patients.

Knockdown of liver cancer cell-secreted exosomal PSMA5 controls macrophage polarization to restrain cancer progression by blocking JAK2/STAT3 signaling

INTRODUCTION

Tumor-associated macrophages, a major component of the tumor microenvironment, undergo polarization into M2 macrophages (M2), and thereby exert an immunosuppressive effect to induce cancer metastasis. This study strives to uncover a molecular mechanism underlying this event in hepatocellular carcinoma (HCC).

METHODS

Proteasome subunit alpha 5 (PSMA5) expression in liver hepatocellular carcinoma (LIHC) tissues and its association with LIHC patients were predicted using StarBase. PSMA5 level in human HCC cells was manipulated via transfection. Exosomes were isolated from HCC cells, and internalized into macrophages which were cocultured with HCC cells. Exosome internalization was observed after fluorescence labeling. HCC cell migration and invasion were evaluated by wound healing and Transwell assays. Xenograft assay was performed to investigate the role of PSMA5 in in vitro tumorigenesis. M2 polarization was assessed by enzyme-linked immunosorbent assay, quantitative reverse transcription polymerase chain reaction, and immunohistochemistry. PSMA5 expression in exosomes and Janus Kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) activation in macrophages and tumors were detected by Western blot analysis.

RESULTS

High PSMA5 expression was observed in LIHC tissues and associated with compromised survival of LIHC patients. PSMA5 knockdown inhibited HCC cell migration and invasion. PSMA5 knockdown in HCC cells downregulated PSMA5 level in exosomes from these HCC cells. HCC cell-isolated exosomes were successfully internalized into macrophages, and facilitated M2 polarization and JAK2/STAT3 pathway activation. HCC cell-secreted exosomal PSMA5 knockdown inhibited the exosome-induced effect on macrophages, and attenuated the promotion induced by exosome-treated macrophages on HCC cell migration/invasion and tumorigenesis along with in vivo M2 polarization and JAK2/STAT3 pathway activation.

CONCLUSION

HCC cell-secreted exosomal PSMA5 knockdown hinders M2 polarization to suppress cancer progression by restraining JAK2/STAT3 signaling.

Lithium Chloride Promotes Endogenous Synthesis of CLA in Bovine Mammary Epithelial Cells

Although conjugated linoleic acid (CLA) can promote human health, its content in milk is insufficient to have a significant impact. The majority of the CLA in milk is produced endogenously by the mammary gland. However, research on improving its content through nutrient-induced endogenous synthesis is relatively scarce. Previous research found that the key enzyme, stearoyl-CoA desaturase (SCD) for the synthesis of CLA, can be expressed more actively in bovine mammary epithelial cells (MAC-T) when lithium chloride (LiCl) is present. This study investigated whether LiCl can encourage CLA synthesis in MAC-T cells. The results showed that LiCl effectively increased SCD and proteasome α5 subunit (PSMA5) protein expression in MAC-T cells as well as the content of CLA and its endogenous synthesis index. LiCl enhanced the expression of proliferator-activated receptor-γ (PPARγ), sterol regulatory element-binding protein 1 (SREBP1), and its downstream enzymes acetyl CoA carboxylase (ACC), fatty acid synthase (FASN), lipoprotein lipase (LPL), and Perilipin 2 (PLIN2). The addition of LiCl significantly enhanced p-GSK-3β, β-catenin, p-β-catenin protein expression, hypoxia-inducible factor-1α (HIF-1α), and downregulation factor genes for mRNA expression (P < 0.05). These findings highlight that LiCl can increase the expression of SCD and PSMA5 by activating the transcription of HIF-1α, Wnt/β-catenin, and the SREBP1 signaling pathways to promote the conversion of trans-vaccenic acid (TVA) to the endogenous synthesis of CLA. This data suggests that the exogenous addition of nutrients can increase CLA content in milk through pertinent signaling pathways.

An immune-related exosome signature predicts the prognosis and immunotherapy response in ovarian cancer

BACKGROUND

Cancer-derived exosomes contribute significantly in intracellular communication, particularly during tumorigenesis. Here, we aimed to identify two immune-related ovarian cancer-derived exosomes (IOCEs) subgroups in ovarian cancer (OC) and establish a prognostic model for OC patients based on immune-related IOCEs.

METHODS

The Cancer Genome Atlas (TCGA) database was used to obtain RNA-seq data, as well as clinical and prognostic information. Consensus clustering analysis was performed to identify two IOCEs-associated subgroups. Kaplan-Meier analysis was used to compare the overall survival (OS) between IOCEs-high and IOCEs-low subtype. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted to investigate the mechanisms and biological effects of differentially expressed genes (DEGs) between the two subtypes. Besides, an IOCE-related prognostic model of OC was constructed by Lasso regression analysis, and the signature was validated using GSE140082 as the validation set.

RESULTS

In total, we obtained 21 differentially expressed IOCEs in OC, and identified two IOCE-associated subgroups by consensus clustering. IOCE-low subgroup showed a favorable prognosis while IOCE-high subgroup had a higher level of immune cell infiltration and immune response. GSEA showed that pathways in cancer and immune response were mainly enriched in IOCE-high subgroup. Thus, IOCE-high subgroup may benefit more in immunotherapy treatment. In addition, we constructed a risk model based on nine IOCE-associated genes (CLDN4, AKT2, CSPG5, ALDOC, LTA4H, PSMA2, PSMA5, TCIRG1, ANO6).

CONCLUSION

We developed a novel stratification system for OV based on IOCE signature, which could be used to estimate the prognosis as well as immunotherapy for OC patient.

An Update on Clinical Trials and Potential Therapeutic Strategies in T-Cell Acute Lymphoblastic Leukemia

Current therapies for T-cell acute leukemia are based on risk stratification and have greatly improved the survival rate for patients, but mortality rates remain high owing to relapsed disease, therapy resistance, or treatment-related toxicities/infection. Patients with relapsed disease continue to have poor outcomes. In the past few years, newer agents have been investigated to optimize upfront therapies for higher-risk patients in the hopes of decreasing relapse rates. This review summarizes the progress of chemo/targeted therapies using Nelarabine/Bortezomib/CDK4/6 inhibitors for T-ALL in clinical trials and novel strategies to target NOTCH-induced T-ALL. We also outline immunotherapy clinical trials using monoclonal/bispecific T-cell engaging antibodies, anti-PD1/anti-PDL1 checkpoint inhibitors, and CAR-T for T-ALL therapy. Overall, pre-clinical studies and clinical trials showed that applying monoclonal antibodies or CAR-T for relapsed/refractory T-ALL therapy is promising. The combination of target therapy and immunotherapy may be a novel strategy for T-ALL treatment.

Metabolic regulation of species-specific developmental rates

Animals display substantial inter-species variation in the rate of embryonic development despite a broad conservation of the overall sequence of developmental events. Differences in biochemical reaction rates, including the rates of protein production and degradation, are thought to be responsible for species-specific rates of development^1-3. However, the cause of differential biochemical reaction rates between species remains unknown. Here, using pluripotent stem cells, we have established an in vitro system that recapitulates the twofold difference in developmental rate between mouse and human embryos. This system provides a quantitative measure of developmental speed as revealed by the period of the segmentation clock, a molecular oscillator associated with the rhythmic production of vertebral precursors. Using this system, we show that mass-specific metabolic rates scale with the developmental rate and are therefore higher in mouse cells than in human cells. Reducing these metabolic rates by inhibiting the electron transport chain slowed down the segmentation clock by impairing the cellular NAD⁺/NADH redox balance and, further downstream, lowering the global rate of protein synthesis. Conversely, increasing the NAD⁺/NADH ratio in human cells by overexpression of the Lactobacillus brevis NADH oxidase LbNOX increased the translation rate and accelerated the segmentation clock. These findings represent a starting point for the manipulation of developmental rate, with multiple translational applications including accelerating the differentiation of human pluripotent stem cells for disease modelling and cell-based therapies.

PSMA5 contributes to progression of lung adenocarcinoma in association with the JAK/STAT pathway

Proteasome dysregulation is a common feature of cancer and a critical risk for tumorigenesis. However, the characteristics of proteasome components in tumor development and metastasis are poorly understood. PSMA5, an α5 subunit of the 20S core proteasome, is associated with the degradation of intracellular proteins. Increasing evidence indicated it is involved in tumor development, but the underlying mechanism has remained unknown. Here, we show that PSMA5 is up-regulated in lung adenocarcinoma (LUAD) cells and clinical LUAD tissues. Moreover, its up-regulation is positively associated with lymph node metastasis and the poor prognosis of LUAD patients. PSMA5 knockdown inhibited the proliferation, invasion and metastasis of LUAD cells in vitro and in vivo, induced apoptosis of LUAD cells and sensitized LUAD cells to cisplatin. Further investigations revealed that PSMA5 overexpression inhibited cell apoptosis by activating the janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway in LUAD cells. In total, our results demonstrate that PSMA5 may function as a prognostic factor in LUAD. In addition, PSMA5 is a promising therapeutic target for LUAD, as its depletion induces cell apoptosis by inhibiting the JAK/STAT pathway.

Single-Molecule RNA Sequencing Reveals IFNγ-Induced Differential Expression of Immune Escape Genes in Merkel Cell Polyomavirus-Positive MCC Cell Lines

Merkel cell carcinoma (MCC) is a rare and highly aggressive cancer, which is mainly caused by genomic integration of the Merkel cell polyomavirus and subsequent expression of a truncated form of its large T antigen. The resulting primary tumor is known to be immunogenic and under constant pressure to escape immune surveillance. Because interferon gamma (IFNγ), a key player of immune response, is secreted by many immune effector cells and has been shown to exert both anti-tumoral and pro-tumoral effects, we studied the transcriptomic response of MCC cells to IFNγ. In particular, immune modulatory effects that may help the tumor evade immune surveillance were of high interest to our investigation. The effect of IFNγ treatment on the transcriptomic program of three MCC cell lines (WaGa, MKL-1, and MKL-2) was analyzed using single-molecule sequencing via the Oxford Nanopore platform. A significant differential expression of several genes was detected across all three cell lines. Subsequent pathway analysis and manual annotation showed a clear upregulation of genes involved in the immune escape of tumor due to IFNγ treatment. The analysis of selected genes on protein level underlined our sequencing results. These findings contribute to a better understanding of immune escape of MCC and may help in clinical treatment of MCC patients. Furthermore, we demonstrate that single-molecule sequencing can be used to assess characteristics of large eukaryotic transcriptomes and thus contribute to a broader access to sequencing data in the community due to its low cost of entry.

A Novel Overall Survival Prediction Signature Based on Cancer Stem Cell-Related Genes in Osteosarcoma

Background: Osteosarcoma is the most general bone malignancy that mostly affects children and adolescents. Numerous stem cell-related genes have been founded in distinct forms of cancer. This study aimed at identifying a stem cell-related gene model for the expected assessment of the prognosis of osteosarcoma patients.

Methods: We obtained the genes expression data and relevant clinical materials from Therapeutically Applicable Research to Generate Effective Treatments (TARGET) and Gene Expression Omnibus (GEO) databases. We identified differentially expressed genes (DEGs) from the GEO dataset, whereas prognostic stem cell-related genes were obtained from the TARGET database. Subsequently, univariate, LASSO and multivariate Cox regression analyses were applied to establish the stem cell-related signature. Finally, the prognostic value of the signature was validated in the GEO dataset.

Results: Twenty-five genes were prognostic ferroptosis-related DEGs. Consequently, we identified eight stem cell-related genes as a signature of prognosis of osteosarcoma patients. Then, the Kaplan–Meier (K-M) curve, the AUC value of ROC, and Cox regression analysis verified that the eight stem cell-related gene model were a new and substantial prognostic marker independent of other clinical traits. Moreover, the nomogram on the foundation of risk score and other clinical traits was established for predicting the survival rate of osteosarcoma patients. Biological function analyses displayed that tumor related pathways were affluent.

Conclusion: The expression level of stem cell-related genes offers novel prognostic markers as well as underlying therapeutic targets for the therapy and prevention of osteosarcoma.

Potential role of glucosamine-phosphate N-acetyltransferase 1 in the development of lung adenocarcinoma

Glucosamine-phosphate N-acetyltransferase 1 (GNPNAT1) is a key enzyme associated with glucose metabolism and uridine diphosphate-N-acetylglucosamine biosynthesis. Abnormal GNPNAT1 expression might be associated with carcinogenesis. We analyzed multiple lung adenocarcinoma (LUAD) gene expression databases and verified GNPNAT1 higher expression in LUAD tumor tissues than in normal tissues. Moreover, we analyzed the survival relationship between LUAD patients’ clinical status and GNPNAT1 expression, and found higher GNPNAT1 expression in LUAD patients with unfavorable prognosis. We built GNPNAT1 gene co-expression networks and further annotated the co-expressed genes’ Gene Ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and various associated regulatory factors. These co-expression genes’ functional networks mainly participate in chromosome segregation, RNA metabolic process, and RNA transport. We analyzed GNPNAT1 genetic alterations and co-occurrence networks, and the functional networks of these genes showed that GNPNAT1 participates in multiple steps of cell cycle transition and in the development of some cancers. We assessed the correlation between GNPNAT1 expression and cancer immune infiltrates and showed that GNPNAT1 expression is correlated with several immune cells, chemokines, and immunomodulators in LUAD. We found that GNPNAT1 correlates with LUAD development and prognosis, laying a foundation for further research, especially in immunotherapy.

Clinical Significance, Cellular Function, and Potential Molecular Pathways of CCT7 in Endometrial Cancer

Objective: Endometrial cancer (EC) is a common gynecologic malignancy; myometrial invasion (MI) is a typical approach of EC spreads and an important index to assess tumor metastasis and outcome in EC patients. CCT7 is a member of the TCP1 chaperone family, involved in cytoskeletal protein folding and unfolding. In this study, the role of CCT7 in EC development was investigated. Methods: Clinical data for 87 EC cases and expression of CCT7 were analyzed. CCT7 was knocked out using siRNA-CCT7 in Ishikawa and RL95-2 cells, and their function about proliferation, apoptosis, and invasion was further tested. Bioinformatics methods were used to predict the potential pathways of CCT7 in EC development. Results: The rates of CCT7-positive cells in EC and adjacent normal endometrium tissues had a significant difference (67.8 vs. 51.4%, p = 0.035), and the expression rate increased from low to high pathological stage (39.7% in the I/II stage, 71.4% in the III/IV stage, p = 0.029). A similar change was found in protein level. CCT7 expression differed significantly between the deep MI group (>1/2) and the superficial MI group (≤1/2) (p = 0.039). However, there were no differences with respect to age, pathological type, and histological grade. CCT7 suppression induced a function loss in both Ishikawa and RL95-2 cells. Bioinformatics analysis demonstrated that EC patients with lower-level CCT7 expression had better overall survival (p = 0.0081). Gene ontology enrichment indicated that "RNA binding," "Mitochondrion," "Translation," and "Spliceosome" were most significantly enriched potential pathways. Five hub genes, PSMA5, PSMD14, SNRPB, SNRPG, and TXNL4A, were all significantly upregulated in EC and had a positive correlation with CCT7. Conclusions: CCT7 may be involved in EC development by excessively activating tumor cell function to promote MI or distant/nodal metastasis, which may contribute to the prognosis of EC patients.