The High Expression of RRM2 Can Predict the Malignant Transformation of Endometriosis

Overexpression of FOS enhances the malignant potential of eutopic endometrial stromal cells in patients with endometriosis‑associated ovarian cancer

Endometrial cysts of the ovary (EMC) may develop into endometriosis (EM)‑associated ovarian cancer over time (EAOC), but the pathogenesis of this disease has not been determined. In the present study, RNA sequencing was used to identify a feasible biomarker, and the molecular function of this biomarker in eutopic endometrial cells from EAOC and EMC patients was evaluated to explore the potential mechanism related to EAOC and orthotopic endometrial tissue. RNA sequencing was performed on 5 EAOC and 4 EMC tissue samples, and differential expression analysis was performed. To identify biomarkers, differentially expressed genes were subjected to protein‑protein interaction network design, Gene Ontology pathway enrichment, and Gene Set Enrichment Analysis pathway enrichment. The expression of FOS in the endometrium was detected via immunohistochemical staining. Lv‑FOS was utilized to upregulate FOS in human endometrial stromal cells (hEnSCs), and Cell Counting Kit‑8, colony formation and scratch assays were performed to assess cell viability, proliferation and migration, respectively. Western blotting was used to determine protein expression. In total, 249 genes, including FOS, were differentially expressed. Pathway enrichment analysis demonstrated that the MAPK, AP‑1, ERK and other signaling pathways were involved in the EMC‑to‑EAOC conversion. FOS upregulation in hEnSCs increased cell viability, proliferation and migration. Western blot results revealed that after FOS expression was inhibited, P21 expression was upregulated, and CDK4, Cyclin D1, p‑Stat3, MMP2 and MMP9 expression was downregulated. In conclusion, mitosis and the cell cycle were found to affect the progression of EMC to EAOC. The expression of FOS, a novel biomarker, was identified to enhance the malignant potential of eutopic endometrial stromal cells in patients with EM‑associated ovarian cancer.

Identification and prognostic analysis of metabolic genes associated with TP53 mutation in multiple myeloma

BACKGROUND

TP53 gene mutation is crucial in determining the prognosis of Multiple Myeloma (MM) patients. Understanding metabolic genes linked to TP53 mutation is vital for developing targeted therapies for these patients.

METHOD

We analyzed The Cancer Genome Atlas (TCGA) dataset to identify genes related to TP53 mutation and metabolism. Using univariate Cox regression and protein-protein interaction (PPI) analysis, we identified key genes. We categorized patients into high and low metabolism groups via non-negative matrix factorization (NMF) clustering, which led to the discovery of relevant differential genes. Integrating these with genes from the Gene Expression Omnibus (GEO) datasets and PPI interactions, we pinpointed crucial metabolic genes associated with TP53 mutation in MM. Additionally, we conducted prognostic analyses involving survival curves and receiver operating characteristic (ROC) charts.

RESULTS

Our study reveals that the metabolic gene ribonucleotide reductase M2 (RRM2), linked to TP53 mutation, correlates positively with the International Staging System (ISS) stage in MM patients and is an independent prognostic risk factor. In the TCGA dataset, among the 767 patients, the 35 MM patients with TP53 mutation generally had poor survival outcomes. Specifically, the patients with both TP53 mutation and high RRM2 expression had a 2-year survival rate of only 38.87%, whereas those with normal TP53 function and low RRM2 expression had a 2-year survival rate of 86.31% (p < 0.001).

CONCLUSION

RRM2 significantly impacts MM prognosis and is associated with TP53 mutation, presenting itself as a potential therapeutic target and prognostic marker for MM.

HBx promotes tumorigenicity through RRM2-mediated autophagy in hepatocellular carcinoma

BACKGROUND

Hepatitis B virus (HBV) infection can exacerbate liver disease progression through multiple mechanisms, eventually leading to hepatocellular carcinoma (HCC). HBV-encoded oncogene X protein (HBx), a key regulatory protein of HBV infection, serves as a positive regulator of hepatocarcinogenesis. The indispensability of the M2 subunit of ribonucleotide-diphosphate reductase (RRM2) lies in its role in facilitating DNA replication and repair processes. In our previous investigation, it was postulated that the gene RRM2 exhibits elevated expression levels in several categories of malignant tumors, particularly in HBV-related HCC. Additionally, it was observed that RRM2 is present within protein complexes that are centered on HBx. In the present investigation, the objective of this work was to investigate the potential relationship between the elevated expression of RRM2 in HBV-related HCC and the influence of HBx on this expression. The study attempted to determine the specific mechanism by which RRM2 is implicated in the promotion of hepatocarcinogenesis by HBx. There have been multiple scholarly proposals suggesting that the induction of autophagy by HBx is a significant intermediary factor in the development of HCC. However, the precise carcinogenic function of HBx-induced autophagy remains a subject of debate.

RESULTS

This work initially investigated the impact of suppressing cellular autophagy on the malignant biological behaviors of HBx-promoted cells using an in vitro cellular model. The findings revealed that the suppression of cellular autophagy partially disrupted the oncogenic effects of HBx. In light of this, we proceeded to conduct more investigations into the regulatory association between RRM2 and HBx-induced autophagy in the upstream-downstream context. Our data indicate that HBx proteins increase the expression of RRM2. Suppression of RRM2 expression not only hinders HBx-induced autophagy, but also worsens the cellular G1/S blockage and reduces the HBx-induced malignant growth of hepatocellular carcinoma tumors, while stimulating apoptosis.

CONCLUSIONS

Therefore, we hypothesised that RRM2 is a potential downstream target of HBx-induced hepatocarcinogenesis, and mining the oncogenic mechanism of RRM2 is significant in exploring the preventive treatment of HBV-related HCC.

Precise capture of circulating endometrial cells in endometriosis

BACKGROUND

Endometriosis (EM) is a complex benign gynecological disease, but it has malignant biological behavior and can invade any part of the body. Clinical manifestations include pelvic pain, dysmenorrhea, infertility, pelvic nodules, and masses. Our previous study successfully detected circulating endometrial cells (CECs) in the peripheral blood of patients with EM. The purpose of this study is to overcome the limitation of cell size in the previous microfluidic chip method, to further accurately capture CECs, understand the characteristics of these cells, and explore the relationship between CECs and the clinical course characteristics of patients with EM.

METHODS

Human peripheral venous blood used to detect CECs and circulating vascular endothelial cells (CVECs) was taken from EM patients ( n = 34) hospitalized in the Peking University People's Hospital. We used the subtraction enrichment and immunostaining fluorescence in situ hybridization (SE-iFISH) method to exclude the interference of red blood cells, white blood cells, and CVECs, so as to accurately capture the CECs in the peripheral blood of patients with EM. Then we clarified the size and ploidy number of chromosome 8 of CECs, and a second grouping of patients was performed based on clinical characteristics to determine the relationship between CECs and clinical course characteristics.

RESULTS

The peripheral blood of 34 EM patients and 12 non-EM patients was evaluated by SE-iFISH. Overall, 34 eligible EM patients were enrolled. The results showed that the detection rates of CECs were 58.8% in EM patients and 16.7% in the control group. However, after classification according to clinical characteristics, more CECs could be detected in the peripheral blood of patients with rapidly progressive EM, with a detection rate of 94.4% (17/18). In total, 63.5% (40/63) of these cells were small cells with diameters below 5 μm, and 44.4% (28/63) were aneuploid cells. No significant association was found between the number of CECs and EM stage.

CONCLUSION

The number and characteristics of CECs are related to the clinical course characteristics of patients with EM, such as pain and changes in lesion size, and may be used as biomarkers for personalized treatment and management of EM in the future.

Targeting of RRM2 suppresses DNA damage response and activates apoptosis in atypical teratoid rhabdoid tumor

BACKGROUND

Atypical teratoid rhabdoid tumors (ATRT) is a rare but aggressive malignancy in the central nervous system, predominantly occurring in early childhood. Despite aggressive treatment, the prognosis of ATRT patients remains poor. RRM2, a subunit of ribonucleotide reductase, has been reported as a biomarker for aggressiveness and poor prognostic conditions in several cancers. However, little is known about the role of RRM2 in ATRT. Uncovering the role of RRM2 in ATRT will further promote the development of feasible strategies and effective drugs to treat ATRT.

METHODS

Expression of RRM2 was evaluated by molecular profiling analysis and was confirmed by IHC in both ATRT patients and PDX tissues. Follow-up in vitro studies used shRNA knockdown RRM2 in three different ATRT cells to elucidate the oncogenic role of RRM2. The efficacy of COH29, an RRM2 inhibitor, was assessed in vitro and in vivo. Western blot and RNA-sequencing were used to determine the mechanisms of RRM2 transcriptional activation in ATRT.

RESULTS

RRM2 was found to be significantly overexpressed in multiple independent ATRT clinical cohorts through comprehensive bioinformatics and clinical data analysis in this study. The expression level of RRM2 was strongly correlated with poor survival rates in patients. In addition, we employed shRNAs to silence RRM2, which led to significantly decrease in ATRT colony formation, cell proliferation, and migration. In vitro experiments showed that treatment with COH29 resulted in similar but more pronounced inhibitory effect. Therefore, ATRT orthotopic mouse model was utilized to validate this finding, and COH29 treatment showed significant tumor growth suppression and prolong overall survival. Moreover, we provide evidence that COH29 treatment led to genomic instability, suppressed homologous recombinant DNA damage repair, and subsequently induced ATRT cell death through apoptosis in ATRT cells.

CONCLUSIONS

Collectively, our study uncovers the oncogenic functions of RRM2 in ATRT cell lines, and highlights the therapeutic potential of targeting RRM2 in ATRT. The promising effect of COH29 on ATRT suggests its potential suitability for clinical trials as a novel therapeutic approach for ATRT.

Expression Profiles of Genes Related to Development and Progression of Endometriosis and Their Association with Paraben and Benzophenone Exposure

Increasing evidence has been published over recent years on the implication of endocrine-disrupting chemicals (EDCs), including parabens and benzophenones in the pathogenesis and pathophysiology of endometriosis. However, to the best of our knowledge, no study has been published on the ways in which exposure to EDCs might affect cell-signaling pathways related to endometriosis. We aimed to describe the endometriotic tissue expression profile of a panel of 23 genes related to crucial cell-signaling pathways for the development and progression of endometriosis (cell adhesion, invasion/migration, inflammation, angiogenesis, and cell proliferation/hormone stimulation) and explore its relationship with the exposure of patients to parabens (PBs) and benzophenones (BPs). This cross-sectional study included a subsample of 33 women with endometriosis from the EndEA study, measuring their endometriotic tissue expressions of 23 genes, while urinary concentrations of methyl-, ethyl-, propyl-, butyl-paraben, benzophenone-1, benzophenone-3, and 4-hydroxybenzophenone were determined in 22 women. Spearman's correlations test and linear and logistic regression analyses were performed. The expression of 52.2% of studied genes was observed in >75% of endometriotic tissue samples and the expression of 17.4% (n = 4) of them in 50-75%. Exposure to certain PB and BP congeners was positively associated with the expression of key genes for the development and proliferation of endometriosis. Genes related to the development and progression of endometriosis were expressed in most endometriotic tissue samples studied, suggesting that exposure of women to PBs and BPs may be associated with the altered expression profile of genes related to cellular pathways involved in the development of endometriosis.

Ribonucleotide reductase regulatory subunit M2 (RRM2) as a potential sero-diagnostic biomarker in non-small cell lung cancer

OBJECTIVES

Non-small cell lung cancer (NSCLC) is a major cause of cancer-related death worldwide. Most cases are diagnosed at an advanced stage using current tumor markers. Here, we aimed to identify potential novel potential biomarkers for NSCLC.

MATERIAL/METHODS

Four independent datasets from the Gene Expression Omnibus database were analyzed. The relative expression of ribonucleotide reductase regulatory subunit M2 (RRM2) mRNA in 30 paired of NSCLC paired tissues was measured by reverse transcription quantitative PCR. Serum levels of cytokeratin fragment 21-1 (CYFRA21-1), pro-gastrin-releasing peptide (ProGRP), carcinoembryonic antigen (CEA), and neuron-specific enolase (NSE) were measured using electrochemiluminescence immunoassays, and serum RRM2 levels were evaluated by an enzyme-linked immunosorbent assay.

RESULTS

The mRNA expression level of RRM2 was significantly increased in most NSCLC lesions compared to para-adjacent tissues. Serum RRM2 levels in NSCLC patients were significantly elevated compared to healthy controls and were also associated with distant metastasis and histological type, but not with tumor size or lymph node metastasis. Receiver operating characteristic curve analysis showed a higher diagnostic ratio for NSCLC using RRM2 alone compared to other traditional tumor markers.

CONCLUSIONS

RRM2 is a potential sero-diagnostic biomarker for NSCLC.

Identification of iron metabolism-related predictive markers of endometriosis and endometriosis-relevant ovarian cancer

Endometriosis is associated with ovarian cancers, mainly endometrioid and clear-cell carcinomas. Iron metabolism has been shown to play a role in endometriosis. Therefore, it is vital to explore the relationship between iron metabolism and ovarian cancer and to identify novel markers for diagnostics and therapeutics. The endometriosis dataset GSE51981 and the ovarian cancer dataset GSE26712 were obtained from the gene expression omnibus database, and differentially expressed genes were identified. Iron metabolism genes were obtained from molecular signatures database, and hub genes from the 3 datasets were obtained. Seven hub genes were identified by bioinformatic analysis, and 3 hub genes (NCOA4, ETFDH, and TYW1) were further selected by logistic regression, which were verified in an independent endometriosis dataset (GSE25628) and ovarian cancer dataset (GSE14407), showing good predictive diagnostic value (area under the receiver operating characteristic curve of 0.88 and 0.9, respectively). Gene Ontology, gene set enrichment analysis, and immune infiltration analysis further confirmed the related functions, pathways, and immune relationship between iron metabolism and ovarian cancer. This study highlights the potential of targeting iron metabolism in the prevention of potential ovarian cancer and in the further exploration of endometriosis and endometriosis-relevant ovarian cancer therapeutics.

Meta-Analysis and Multivariate GWAS Analyses in 80,950 Individuals of African Ancestry Identify Novel Variants Associated with Blood Pressure Traits

High blood pressure (HBP) has been implicated as a major risk factor for cardiovascular diseases in several populations, including individuals of African ancestry. Despite the elevated burden of HBP-induced cardiovascular diseases in Africa and other populations of African descent, limited genetic studies have been carried out to explore the genetic mechanism driving this phenomenon. We performed genome-wide association univariate and multivariate analyses of both systolic (SBP) and diastolic blood pressure (DBP) traits in 80,950 individuals of African ancestry. We used summary statistics data from six independent cohorts, including the African Partnership for Chronic Disease Research (APCDR), the UK Biobank, and the Million Veteran Program (MVP). FUMA was used to annotate, prioritize, visualize, and interpret our findings to gain a better understanding of the molecular mechanism(s) underlying the genetics of BP traits. Finally, we undertook a Bayesian fine-mapping analysis to identify potential causal variants. Our meta-analysis identified 10 independent variants associated with SBP and 9 with DBP traits. Whilst our multivariate GWAS method identified 21 independent signals, 18 of these SNPs have been previously identified. SBP was linked to gene sets involved in biological processes such as synapse assembly and cell-cell adhesion via plasma membrane adhesion. Of the 19 independent SNPs identified in the BP meta-analysis, only 11 variants had posterior probability (PP) of > 50%, including one novel variant: rs562545 (MOBP, PP = 77%). To facilitate further research and fine-mapping of high-risk loci/variants in highly susceptible groups for cardiovascular disease and other related traits, large-scale genomic datasets are needed. Our findings highlight the importance of including ancestrally diverse populations in large GWASs and the need for diversity in genetic research.

A pan-cancer analysis of the oncogenic role of ribonucleotide reductase subunit M2 in human tumors

Background

Recent studies have identified ribonucleotide reductase subunit M2 (RRM2) as a putative promoter of tumors. However, no systematic analysis of its carcinogenicity has been conducted.

Methods

The potential functions of RRM2 in various tumor types were investigated using data from the Genotype-Tissue Expression (GTEx), the Clinical Proteomic Tumor Analysis Consortium (CPTAC), the Cancer Genome Atlas (TCGA), the Human Protein Atlas (HPA), cBioPortal, GEPIA, String, and Gene Set Enrichment Analysis (GSEA). We analyzed the difference in mRNA and protein expression, pathological stage, survival, mutation, tumor microenvironment (TME), and immune cell infiltration in relation to RRM2. Meanwhile, using TCGA and the Tumor Immune Estimation Resource 2 (TIMER 2), the associations between RRM2 expression, immune infiltration, and immune-related genes were assessed. Additionally, CCK-8, Edu and RT-PCR assays were used to validate that RRM2 acts as an oncogene in liver cancer cells and its association with HBx. A cohort of liver hepatocellular carcinoma (LIHC) patients (n=154) from Huashan Hospital was analyzed for the expression of RRM2 and the association between RRM2 and immune infiltration.

Results

Using the GTEx and TCGA databases, we discovered that 28 tumors expressed RRM2 at significantly higher levels than the corresponding normal tissues. Increased RRM2 expression may be predictive of a poor overall survival (OS) in patients with seven different cancers. GO, KEGG, and GSEA analyses revealed that the biological process of RRM2 was associated with the regulation of carcinogenic processes and immune pathways in a variety of tumor types. The expression of RRM2 was highly correlated with maker genes involved in immune activation and immunosuppression, immune checkpoints, DNA mismatch repair system (MMR), and the infiltration levels of Tregs and macrophages (TAMs), suggesting that the carcinogenic effect of RRM2 may be achieved by regulating immune related genes. Moreover, as demonstrated by CCK-8 and Edu assays, RRM2 was an oncogene in liver cancer cells. We confirmed for the first time that RRM2 was significantly upregulated by HBx, suggesting that RRM2 may be a key regulator of LIHC induced by HBV. IHC analysis validated the upregulated expression of RRM2 protein and its correlation with immune infiltration makers in a LIHC patient cohort.

Conclusion

RRM2 may be a valuable molecular biomarker for predicting prognosis and immunotherapeutic efficacy in pan-cancer, particularly in LIHC.

Comprehensive Analysis of circRNA-Mediated ceRNA Regulatory Networks in relation to Recurrent Implantation Failure

Recurrent implantation failure (RIF) is attributed to endometrial receptivity dysfunction with many unanswered questions. Up to now, there is no explanation for RIF, and therapeutic strategies are usually limited to supportive care. In this study, we differentially analyzed the raw data deposited in three eligible microarray datasets, GSE111974, GSE121219, and GSE147442 to screen DE-mRNAs, DE-miRNAs, and DE-circRNAs, respectively. The value of log2-fold change |log2FC| ≥ 1 and the adjusted p value < 0.05 were considered differentially expressed between RIF and fertile control. We found 350 DE-mRNAs, 43 DE-miRNAs, and 1968 DE-circRNAs between RIF and fertile control. The PPI network identified 6 hub genes with degree ≥10, KDR, AGT, POSTN, TOP2A, RRM2, and PTGS2, in RIF. KDR, AGT, POSTN, TOP2A, and RRM2 were downregulated in endometrial tissue samples of RIF compared with those of fertile control, while PTGS2 was upregulated in endometrial tissue samples of RIF compared with those of fertile control. According to the ceRNA hypothesis, 15 groups of ceRNA network based on 10 circRNAs, hsa_circ_001572, hsa_circ_001884, hsa_circ_001375, hsa_circ_001449, hsa_circ_000029, hsa_circ_001168, hsa_circ_000210, hsa_circ_001484, hsa_circ_001698, and hsa_circ_000089 were constructed in RIF. In conclusion, the present study examined the possible role of circRNAs and their related ceRNA network involved in the pathogenesis of RIF.

Comprehensive Landscape of RRM2 with Immune Infiltration in Pan-Cancer

Simple Summary

RRM2 is a crucial subunit of ribonucleotide reductase. In this article, we provided a comprehensive analysis of RRM2 with immune infiltration in pan-cancer. We focused on the hotspots of ferroptosis-related gene RRM2 and immunotherapy. Via bioinformatics analysis, multiple indicators suggested that RRM2 high expression may enhance immunotherapy sensitivity. For the first time, we systematically analyzed the role of RRM2 in pan-cancer. We provided the prospect of RRM2 and immunotherapy for pan-cancer. Additionally, we proved the expression pattern, clinical value, prognostic value and potential pathways of RRM2 with different platforms. In particular, we confirmed RRM2 expression and function in bladder cancer in our clinical samples and cell lines. Collectively, we found that RRM2 is a novel prognostic biomarker, and these findings may aid in an improved understanding of the role of RRM2 and its clinical application in human cancers.

Abstract

As a crucial subunit of ribonucleotide reductase, RRM2 plays a significant part in DNA synthesis. This study aimed to elucidate the comprehensive landscape of RRM2 in human cancers. With different bioinformatics platforms, we investigated the expression pattern, prognostic significance, mutational landscapes, gene interaction network, signaling pathways and immune infiltration of RRM2 in tumors. We found that RRM2 expression was predominantly up-expressed in tumor tissues in most tumors. Concurrently, RRM2 expression was significantly associated with worse prognosis and tumor stage across TCGA cancers. Moreover, RRM2 high levels were critically associated with the infiltration of natural killer T cells and immune scores. RRM2 was positively related to immune checkpoints, tumor mutation burden, microsatellite instability, neoantigen, and cytotoxic T lymphocyte in several cancers, predicting effective response to immunotherapy. Meanwhile, a strong co-expression of RRM2 with immune-related genes was observed. Additionally, multiple Cox regression analysis showed that RRM2 was an independent prognostic factor in bladder cancer (BLCA). Eventually, we verified that RRM2 was overexpressed in BLCA clinical samples and cell lines. Blocking RRM2 could suppress BLCA cells’ growth and proliferation while enhancing sensitivity to cisplatin. This study provided a new perspective for understanding RRM2 in cancers and new strategies for tumor immunotherapy.