Impact of hypoxia on cervical cancer outcomes

Construction of a ferroptosis and hypoxia-related gene signature in cervical cancer to assess tumour immune microenvironment and predict prognosis

BACKGROUND

This study aimed to investigate the potential role of ferroptosis/hypoxia-related genes in cervical cancer to improve early management and treatment of cervical cancer.

METHODS

All data were downloaded from public databases. Ferroptosis/hypoxia-related genes associated with cervical cancer prognosis were selected to construct a risk score model. The relationship between risk score and clinical features, immune microenvironment and prognosis were analysed.

RESULTS

Risk score model was constructed based on eight signature genes. Drug prediction analysis showed that bevacizumab and cisplatin were related to vascular endothelial growth factor A. Risk score, as an independent prognostic factor of cervical cancer, had a good survival prediction effect. The two groups differed significantly in degree of immune cell infiltration, gene expression, tumour mutation burden and somatic variation.

CONCLUSIONS

We developed a novel prognostic gene signature combining ferroptosis/hypoxia-related genes, which provides new ideas for individual treatment of cervical cancer.

LOC644656 promotes cisplatin resistance in cervical cancer by recruiting ZNF143 and activating the transcription of E6-AP

Cisplatin resistance remains a persistent challenge in cervical cancer (CC) treatment. Molecular biomarkers have garnered attention for their association with cisplatin resistance in various diseases. Long non-coding RNAs (lncRNAs) exert significant influence on CC development. This study explores the role of LOC644656 in regulating cisplatin resistance in CC. Parental and cisplatin-resistant CC cells underwent cisplatin treatment. Functional assays assessed cell proliferation and apoptosis under different conditions. RNA pull-down with mass spectrometry, along with literature review, elucidated the interaction between LOC644656, ZNF143, and E6-AP. Mechanistic assays analyzed the relationship between different factors. RT-qPCR and western blot quantified RNA and protein levels, respectively. In vivo models validated E6-AP's function. Results revealed LOC644656 overexpression in cisplatin-resistant CC cells, exacerbating cell growth. LOC644656 recruited ZNF143 to activate E6-AP transcription, promoting cisplatin resistance in CC. In conclusion, LOC644656 positively modulates E6-AP expression via ZNF143-mediated transcriptional activation, contributing to cisplatin resistance in CC.

EPAS1, a hypoxia- and ferroptosis-related gene, promotes malignant behaviour of cervical cancer by ceRNA and super-enhancer

Hypoxia and Ferroptosis are associated with the malignant behaviour of cervical cancer. Endothelial PAS domain-containing protein 1 (EPAS1) contributes to the progression of cervical cancer. EPAS1 plays important roles in hypoxia and ferroptosis. Using the GEO dataset, machine-learning algorithms were used to screen for hypoxia- and ferroptosis-related genes (HFRGs) in cervical cancer. EPAS1 was identified as the hub gene. qPCR and WB were used to investigate the expression of EPAS1 in normal and cervical cancer tissues. The proliferation, invasion and migration of EPAS1 cells in HeLa and SiHa cell lines were detected using CCK8, transwell and wound healing assays, respectively. Apoptosis was detected by flow cytometry. A dual-luciferase assay was used to analyse the MALAT1-miR-182-5P-EPAS1 mRNA axis and core promoter elements of the super-enhancer. EPAS1 was significantly overexpressed in cervical cancer tissues. EPAS1 could increase the proliferation, invasion, migration of HeLa and SiHa cells and reduce the apoptosis of HeLa and SiHa cell. According to the double-luciferase assay, EPAS1 expression was regulated by the MALAT1-Mir-182-5p-EPAS1 mRNA axis. EPAS1 is associated with super-enhancers. Double-luciferase assay showed that the core elements of the super-enhancer were E1 and E3. EPAS1, an HFRG, is significantly overexpressed in cervical cancer. EPAS1 promotes malignant behaviour of cervical cancer cells. EPAS1 expression is regulated by super-enhancers and the MALAT1-miR-182-5P- EPAS1 mRNA axis. EPAS1 may be a target for the diagnosis and treatment of cervical cancer.

Exploring MiR-484 Regulation by Polyalthia longifolia: A Promising Biomarker and Therapeutic Target in Cervical Cancer through Integrated Bioinformatics and an In Vitro Analysis

BACKGROUND

MiR-484, implicated in various carcinomas, holds promise as a prognostic marker, yet its relevance to cervical cancer (CC) remains unclear. Our prior study demonstrated the Polyalthia longifolia downregulation of miR-484, inhibiting HeLa cells. This study investigates miR-484's potential as a biomarker and therapeutic target in CC through integrated bioinformatics and an in vitro analysis.

METHODS

MiR-484 levels were analyzed across cancers, including CC, from The Cancer Genome Atlas. The limma R package identified differentially expressed genes (DEGs) between high- and low-miR-484 CC cohorts. We assessed biological functions, tumor microenvironment (TME), immunotherapy, stemness, hypoxia, RNA methylation, and chemosensitivity differences. Prognostic genes relevant to miR-484 were identified through Cox regression and Kaplan-Meier analyses, and a prognostic model was captured via multivariate Cox regression. Single-cell RNA sequencing determined cell populations related to prognostic genes. qRT-PCR validated key genes, and the miR-484 effect on CC proliferation was assessed via an MTT assay.

RESULTS

MiR-484 was upregulated in most tumors, including CC, with DEGs enriched in skin development, PI3K signaling, and immune processes. High miR-484 expression correlated with specific immune cell infiltration, hypoxia, and drug sensitivity. Prognostic genes identified were predominantly epidermal and stratified patients with CC into risk groups, with the low-risk group showing enhanced survival and immunotherapeutic responses. qRT-PCR confirmed FGFR3 upregulation in CC cells, and an miR-484 mimic reversed the P. longifolia inhibitory effect on HeLa proliferation.

CONCLUSION

MiR-484 plays a crucial role in the CC progression and prognosis, suggesting its potential as a biomarker for targeted therapy.

Cancer/testis-45A1 promotes cervical cancer cell tumorigenesis and drug resistance by activating oncogenic SRC and downstream signaling pathways

BACKGROUND

Cancer/testis antigen-45A1 (CT45A1) is overexpressed in various types of cancer but is not expressed in healthy women. The role of CT45A1 in cervical cancer has not yet been described in the literature.

PURPOSE

The aim of this research was to study the role of CT45A1 in cervical cancer progression and drug resistance, elucidate the mechanisms underlying CT45A1-mediated tumorigenesis and investigate CT45A1 as a biomarker for cervical cancer diagnosis, prognostic prediction, and targeted therapy.

METHODS

The CT45A1 levels in the tumors from cervical cancer patients were measured using immunohistochemical staining. The role and mechanisms underlying CT45A1-mediated cervical cancer cell tumor growth, invasion, and drug resistance were studied using xenograft mice, cervical cancer cells, immunohistochemistry, RNA-seq, real-time qPCR, Chromatin immunoprecipitation and Western blotting.

RESULTS

CT45A1 levels were notably high in the tumor tissues of human cervical cancer patients compared to the paracancerous tissues (p < 0.001). Overexpression of CT45A1 was closely associated with poor prognosis in cervical cancer patients. CT45A1 promoted cervical cancer cell tumor growth, invasion, neovascularization, and drug resistance. Mechanistically, CT45A1 promoted the expression of 128 pro-tumorigenic genes and concurrently activated key signaling pathways, including the oncogenic SRC, ERK, CREB, and YAP/TAZ signaling pathways. Furthermore, CT45A1-mediated tumorigenesis and drug resistance were markedly inhibited by the small molecule lycorine.

CONCLUSION

CT45A1 promotes cervical cancer cell tumorigenesis, neovascularization, and drug resistance by activating oncogenic SRC and downstream tumorigenic signaling pathways. These findings provide new insight into the pathogenesis of cervical cancer and offer a new platform for the development of novel therapeutics against cervical cancer.

Apigenin 7-glucoside impedes hypoxia-induced malignant phenotypes of cervical cancer cells in a p16-dependent manner

Apigenin 7-glucoside (A7G) can suppress cell proliferation and trigger apoptosis in cervical cancer cells. Considering that hypoxia is associated with the malignant phenotypes in cervical cancer, this study aimed to uncover whether A7G exhibits suppressive effects on the hypoxia-induced malignant phenotype of cervical cancer cells (HeLa cells). Compared to normoxia, hypoxia can enhance the malignant phenotypes of HeLa cells, including cell proliferation, reduced sensitivity against chemotherapeutic agents (oxaliplatin and paclitaxel), cancer stemness, migration, and invasion. A7G intervention (20, 40, and 60 μM) could impair these malignant phenotypes of HeLa cells and upregulate the expression level of total and nuclear p16 proteins. Molecular docking analysis showed the interaction between anion exchanger 1 and A7G. In p16-silencing HeLa cells, the anticancer effects of A7G were absent. Therefore, hypoxia derives malignant phenotypes of HeLa cells, which could be impeded by A7G in a p16-dependent manner.

MRI-guided Pelvic Radiation Therapy: A Primer for Radiologists

Radiation therapy (RT) is a core pillar of oncologic treatment, and half of all patients with cancer receive this therapy as a curative or palliative treatment. The recent integration of MRI into the RT workflow has led to the advent of MRI-guided RT (MRIgRT). Using MRI rather than CT has clear advantages for guiding RT to pelvic tumors, including superior soft-tissue contrast, improved organ motion visualization, and the potential to image tumor phenotypic characteristics to identify the most aggressive or treatment-resistant areas, which can be targeted with a more focal higher radiation dose. Radiologists should be familiar with the potential uses of MRI in planning pelvic RT; the various RT techniques used, such as brachytherapy and external beam RT; and the impact of MRIgRT on treatment paradigms. Current clinical experience with and the evidence base for MRIgRT in the settings of prostate, cervical, and bladder cancer are discussed, and examples of treated cases are illustrated. In addition, the benefits of MRIgRT, such as real-time online adaptation of RT (during treatment) and interfraction and/or intrafraction adaptation to organ motion, as well as how MRIgRT can decrease toxic effects and improve oncologic outcomes, are highlighted. MRIgRT is particularly beneficial for treating mobile pelvic structures, and real-time adaptive RT for tumors can be achieved by using advanced MRI-guided linear accelerator systems to spare organs at risk. Future opportunities for development of biologically driven adapted RT with use of functional MRI sequences and radiogenomic approaches also are outlined. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Role of the tumor microenvironment in the lymphatic metastasis of cervical cancer (Review)

Lymphatic metastasis is the primary type of cervical cancer metastasis and is associated with an extremely poor prognosis in patients. The tumor microenvironment primarily includes cancer-associated fibroblasts, tumor-associated macrophages, myeloid-derived suppressor cells, immune and inflammatory cells, and blood and lymphatic vascular networks, which can promote the establishment of lymphatic metastatic sites within immunosuppressive microenvironments or promote lymphatic metastasis by stimulating lymphangiogenesis and epithelial-mesenchymal transformation. As the most important feature of the tumor microenvironment, hypoxia plays an essential role in lymph node metastasis. In this review, the known mechanisms of hypoxia, and the involvement of stromal components and immune inflammatory cells in the tumor microenvironment of lymphatic metastasis of cervical cancer are discussed. Additionally, a summary of the clinical trials targeting the tumor microenvironment for the treatment of cervical cancer is provided, emphasizing the potential and challenges of immunotherapy.

A critical review on the biosynthesis, properties, applications and future outlook of green MnO2 nanoparticles

MnO2 nanoparticles have played a vital role in biomedical, catalysis, electrochemical and energy storage fields, but requiring toxic chemicals in the fabrication intercepts their applications. There is an increasing demand for biosynthesis of MnO2 nanoparticles using green sources such as plant species in accordance with the purposes of environmental mitigation and production cost reduction. Here, we review recent advancements on the use of natural compounds such as polyphenols, reducing sugars, quercetins, etc. Extracted directly from low-cost and available plants for biogenic synthesis of MnO2 nanoparticles. Role of these phytochemicals and formation mechanism of bio-medicated MnO2 nanoparticles are shed light on. MnO2 nanoparticles own small particle size, high crystallinity, diverse morphology, high surface area and stability. Thanks to higher biocompatibility, bio-mediated synthesized MnO2 nanoparticles exhibited better antibacterial, antifungal, and anticancer activity than chemically synthesized ones. In terms of wastewater treatment and energy storage, they also served as efficient adsorbents and catalyst. Moreover, several aspects of limitation and future outlook of bio-mediated MnO2 nanoparticles in the fields are analyzed. It is expected that the present work not only expands systematic understandings of synthesis methods, properties and applications MnO2 nanoparticles but also pave the way for the nanotechnology revolution in combination with green chemistry and sustainable development.

Compared between support vector machine (SVM) and deep belief network (DBN) for multi-classification of Raman spectroscopy for cervical diseases

In this study, a minimally invasive test method for cervical cancer in vitro was proposed by comparing Raman spectroscopy with support vector machine (SVM) model and deep belief network (DBN) model. The serum Raman spectra of cervical cancer, hysteromyoma, and healthy people were collected. After data processing, SVM classification model and DBN classification model were built respectively. The experimental results show that when the DBN network algorithm is used, the sample test set can be divided accurately and the result of cross-validation is ideal. Compared with the traditional SVM algorithm, this method firstly screened the effective feature matrix from the data, and then classified the data. With high efficiency and accuracy, based on 445 samples collected, this method improved the accuracy by 13.93%±2.47% compared with the SVM method, and provided a new direction and idea for the in vitro diagnosis of cervical diseases.

FOXP3 Isoforms Expression in Cervical Cancer: Evidence about the Cancer-Related Properties of FOXP3Δ2Δ7 in Keratinocytes

Cervical cancer (CC) is the fourth most common type of cancer among women; the main predisposing factor is persistent infection by high-risk human papillomavirus (hr-HPV), mainly the 16 or 18 genotypes. Both hr-HPVs are known to manipulate the cellular machinery and the immune system to favor cell transformation. FOXP3, a critical transcription factor involved in the biology of regulatory T cells, has been detected as highly expressed in the tumor cells of CC patients. However, its biological role in CC, particularly in the keratinocytes, remained unclarified. Therefore, this work aimed to uncover the effect of FOXP3 on the biology of the tumoral cells. First, public databases were analyzed to identify the FOXP3 expression levels and the transcribed isoforms in CC and normal tissue samples. The study's findings demonstrated an increased expression of FOXP3 in HPV16+ CC samples. Additionally, the FOXP3Δ2 variant was detected as the most frequent splicing isoform in tumoral cells, with a high differential expression level in metastatic samples. However, the analysis of FOXP3 expression in different CC cell lines, HPV+ and HPV-, suggests no relationship between the presence of HPV and FOXP3 expression. Since the variant FOXP3Δ2Δ7 was found highly expressed in the HPV16+ SiHa cell line, a model with constitutive expression of FOXP3Δ2Δ7 was established to evaluate its role in proliferation, migration, and cell division. Finally, RNAseq was performed to identify differentially expressed genes and enriched pathways modulated by FOXP3Δ2Δ7. The exogenous expression of FOXP3Δ2Δ7 promotes cell division, proliferation, and migration. The transcriptomic analyses highlight the upregulation of multiple genes with protumor activities. Moreover, immunological and oncogenic pathways were detected as highly enriched. These data support the hypothesis that FOXP3Δ2Δ7 in epithelial cells induces cancer-related hallmarks and provides information about the molecular events triggered by this isoform, which could be important for developing CC.

HIF-3α-Induced miR-630 Expression Promotes Cancer Hallmarks in Cervical Cancer Cells by Forming a Positive Feedback Loop

Purpose. Hypoxia has crucial functions in the development and metastasis of cervical cancer by inducing the expression of numerous genes, including microRNA genes. But we know little about how the hypoxia factors and microRNAs orchestrate to regulate hallmarks of cervical cancer cells. Methods. We conducted RNA sequencing (RNA-seq) and chromatin immunoprecipitation sequencing (ChIP-seq) experiments to investigate the targets of HIF-3α or miR-630. ChIP-qPCR and RT-qPCR were carried out to validate the results of ChIP-seq and RNA-seq. Cellular, molecular, and radiation experiments were conducted to explore the functions of miR-630. Results. In this study, we showed that hypoxia-induced overexpression of HIF-3α increased the expression of dozens of miRNAs, including miR-630. Hypoxia could also directly induce miR-630 expression. ChIP-seq data showed that HIF-3α activates miR-630 expression by directly binding to the promoter of its host gene. Meanwhile, stable overexpression of miR-630 increased the expression of HIF-3α, but repressed the expression of HIF-1α, indicating a positive feedback loop between HIF-3α and miR-630. Consequently, stable overexpression of miR-630 in HeLa cells promotes cancer hallmarks, including radioresistance, inhibition of apoptosis, increased migration and invasion, and EMT-mediated metastasis. Meanwhile, inhibition of miR-630 showed opposite features. Conclusion. Taken together, our findings indicate a novel hypoxia-induced HIF-3α and miR-630 regulatory feedback loop contributing to metastasis and progression of cervical cancer cells and suggest that HIF-3α and miR-630 might act as potential biomarkers and therapeutic targets for cervical cancer in the future.

Comprehensive analyses identify RIPOR2 as a genomic instability-associated immune prognostic biomarker in cervical cancer

Cervical cancer (CC) is a malignancy that tends to have a poor prognosis when detected at an advanced stage; however, there are few studies on the early detection of CC at the genetic level. The tumor microenvironment (TME) and genomic instability (GI) greatly affect the survival of tumor patients via effects on carcinogenesis, tumor growth, and resistance. It is necessary to identify biomarkers simultaneously correlated with components of the TME and with GI, as these could predict the survival of patients and the efficacy of immunotherapy. In this study, we extracted somatic mutational data and transcriptome information of CC cases from The Cancer Genome Atlas, and the GSE44001 dataset from the Gene Expression Omnibus database was downloaded for external verification. Stromal components differed most between genomic unstable and genomic stable groups. Differentially expressed genes were screened out on the basis of GI and StromalScore, using somatic mutation information and ESTIMATE methods. We obtained the intersection of GI- and StromalScore-related genes and used them to establish a four-gene signature comprising RIPOR2, CCL22, PAMR1, and FBN1 for prognostic prediction. We described immunogenomic characteristics using this risk model, with methods including CIBERSORT, gene set enrichment analysis (GSEA), and single-sample GSEA. We further explored the protective factor RIPOR2, which has a close relationship with ImmuneScore. A series of in vitro experiments, including immunohistochemistry, immunofluorescence, quantitative reverse transcription PCR, transwell assay, CCK8 assay, EdU assay, cell cycle detection, colony formation assay, and Western blotting were performed to validate RIPOR2 as an anti-tumor signature. Combined with integrative bioinformatic analyses, these experiments showed a strong relationship between RIPOR2 with tumor mutation burden, expression of genes related to DNA damage response (especially PARP1), TME-related scores, activation of immune checkpoint activation, and efficacy of immunotherapy. To summarize, RIPOR2 was successfully identified through comprehensive analyses of the TME and GI as a potential biomarker for forecasting the prognosis and immunotherapy response, which could guide clinical strategies for the treatment of CC patients.

Exploring the underlying molecular mechanism of liver cancer cells under hypoxia based on RNA sequencing

Background

The aim of our study was to use the differentially expressed mRNAs (DEmRNAs) and differentially expressed miRNAs (DEmiRNAs) to illustrate the underlying mechanism of hypoxia in liver cancer.

Methods

In this study, a cell model of hypoxia was established, and autophagy activity was measured with western blotting and transmission electron microscopy. The effect of hypoxia conditions on the invasion of liver cancer cell was evaluated. RNA sequencing was used to identify DEmRNAs and DEmiRNAs to explore the mechanism of hypoxia in liver cancer cells.

Results

We found that autophagy activation was triggered by hypoxia stress and hypoxia might promote liver cancer cell invasion. In addition, a total of 407 shared DEmRNAs and 57 shared DEmiRNAs were identified in both HCCLM3 hypoxia group and SMMC-7721 hypoxia group compared with control group. Furthermore, 278 DEmRNAs and 24 DEmiRNAs were identified as cancer hypoxia-specific DEmRNAs and DEmiRNAs. Finally, we obtained 19 DEmiRNAs with high degree based on the DEmiRNA-DEmRNA interaction network. Among them, hsa-miR-483-5p, hsa-miR-4739, hsa-miR-214-3p and hsa-miR-296-5p may be potential gene signatures related to liver cancer hypoxia.

Conclusions

Our study may help to understand the potential molecular mechanism of hypoxia in liver cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12863-022-01055-9.