LITAF Enhances Radiosensitivity of Human Glioma Cells via the FoxO1 Pathway

Identification of T-cell exhaustion-related gene signature for predicting prognosis in glioblastoma multiforme

Glioblastoma multiforme (GBM) is a highly malignant primary brain tumour with a poor prognosis in adults. Identifying biomarkers that can aid in the molecular classification and risk stratification of GBM is critical. Here, we conducted a transcriptional profiling analysis of T-cell immunity in the tumour microenvironment of GBM patients and identified two novel T cell exhaustion (TEX)-related GBM subtypes (termed TEX-C1 and TEX-C2) using the consensus clustering. Our multi-omics analysis revealed distinct immunological, molecular and clinical characteristics for these two subtypes. Specifically, the TEX-C1 subtype had higher infiltration levels of immune cells and expressed higher levels of immune checkpoint molecules than the TEX-C2 subtype. Functional analysis revealed that upregulated genes in the TEX-C1 subtype were significantly enriched in immune response and signal transduction pathways, and upregulated genes in the TEX-C2 subtype were predominantly associated with cell fate and nervous system development pathways. Notably, patients with activated T-cell activity status in the TEX-C1 subgroup demonstrated a significantly worse prognosis than those with severe T cell exhaustion status in the TEX-C2 subgroup. Finally, we proposed a machine-learning-derived novel gene signature comprising 12 TEX-related genes (12TexSig) to indicate tumour subtyping. In the TCGA cohort, the 12TexSig demonstrated the ability to accurately predict the prognosis of GBM patients, and this prognostic value was further confirmed in two independent external cohorts. Taken together, our results suggest that the TEX-derived subtyping and gene signature has the potential to serve as a clinically helpful biomarker for guiding the management of GBM patients, pending further prospective validation.

Forkhead box transcription factors (FOXOs and FOXM1) in glioma: from molecular mechanisms to therapeutics

Glioma is the most aggressive and malignant type of primary brain tumor, comprises the majority of central nervous system deaths, and is categorized into different subgroups according to its histological characteristics, including astrocytomas, oligodendrogliomas, glioblastoma multiforme (GBM), and mixed tumors. The forkhead box (FOX) transcription factors comprise a collection of proteins that play various roles in numerous complex molecular cascades and have been discovered to be differentially expressed in distinct glioma subtypes. FOXM1 and FOXOs have been recognized as crucial transcription factors in tumor cells, including glioma cells. Accumulating data indicates that FOXM1 acts as an oncogene in various types of cancers, and a significant part of studies has investigated its function in glioma. Although recent studies considered FOXO subgroups as tumor suppressors, there are pieces of evidence that they may have an oncogenic role. This review will discuss the subtle functions of FOXOs and FOXM1 in gliomas, dissecting their regulatory network with other proteins, microRNAs and their role in glioma progression, including stem cell differentiation and therapy resistance/sensitivity, alongside highlighting recent pharmacological progress for modulating their expression.

LITAF inhibits colorectal cancer stemness and metastatic behavior by regulating FOXO1-mediated SIRT1 expression

Lipopolysaccharide-induced tumor necrosis factor alpha factor (LITAF) is a transcription factor that activates the transcription of TNF-α and regulates the inflammatory response. LITAF has been found to have potential anti-cancer effects of in several tumors. However, the role of LITAF in colorectal cancer (CRC) remains unclear. Through a comprehensive pan-cancer analysis of the Cancer Genome Atlas (TCGA), LITAF was identified as a differentially downregulated gene in CRC. We hypothesized that LITAF may participate in the modulation of CRC progression. The present study was aimed to investigate the expression profile of LITAF in CRC and its effect on metastatic behavior and stemness as well as the underlying molecular mechanism. The expression profile of LITAF in CRC, and its relationship with the prognosis of CRC were explored using public databases. LITAF expression was detected by quantitative real-time PCR (qRT-PCR), western blot, and immunohistochemistry. Furthermore, the effects of overexpression or knockdown of LITAF on cell proliferation, apoptosis, migration, invasion, and stemness of CRC cells were investigated in vitro. The regulatory effect of LITAF on forkhead Box O 1 (FOXO1)-sirtuin 1 (SIRT1) signaling axis was also explored. In addition, a xenograft mouse model was used to investigate the in-vivo role of LITAF. LITAF was downregulated in tumor tissues and its expression was associated with the prognosis, pathological stage and liver metastasis. In-vitro experiments confirmed that LITAF inhibited tumor cell proliferation, migration, invasion and stemness, and induced cell apoptosis. In vivo experiments demonstrated that LITAF inhibited the tumorigenicity and liver metastasis in tumor-bearing mice. Additionally, LITAF promoted FOXO1-mediated SIRT1 inhibition, thus regulating cancer stemness and malignant phenotypes. LITAF was silenced in CRC and it participated in the progression of CRC by inhibiting CRC cell stemness, and malignant phenotypes. Therefore, LITAF may serve as a novel biomarker of CRC prognosis.

Molecular Response of Keloids to Ionizing Radiation: Targeting FOXO1 Radiosensitizes Keloids

PURPOSE

Keloids are benign dermal tumors that arise from abnormal wound healing processes following skin lesions. Surgical excision followed by radiotherapy plays an important role in the treatment of keloids. Nevertheless, radioresistance remains a serious impediment to treatment efficacy. Investigation of the molecular response of keloids to radiation may contribute to radiosensitizing strategies.

MATERIALS AND METHODS

Primary keloid fibroblasts from human keloids were isolated and irradiated with X-ray. The expression profiles of messenger RNA (mRNA) in nonradiated and irradiated primary keloid fibroblasts were measured by mRNA sequencing analysis. Then, we identified common motifs and corresponding transcription factors of dysregulated mRNAs by using bioinformatic analysis of the proximal promoters. Whereafter, GO and KEGG were used to analyse the functional enrichment of the differentially expressed genes.

RESULTS

We found that radiation not only suppressed proliferation but also increased cell senescence of primary keloid fibroblasts. There were 184 mRNAs and 204 mRNAs that showed significant changes in 4 and 8 Gy irradiated primary keloid fibroblasts, respectively. Among them, 8 upregulated and 30 downregulated mRNAs showed consistent alterations in 4 and 8 Gy irradiated primary keloid fibroblasts. More importantly, the forkhead box O1 (FOXO1) signaling pathway was involved in the irradiation response. Pretreatment with the FOXO1 signaling inhibitor AS1842856 significantly promoted LDH release, apoptosis and senescence of primary keloid fibroblasts following irradiation.

CONCLUSION

Our findings illustrated the molecular changes in human keloid fibroblasts in response to radiation, and FOXO1 pathway inhibition is expected to provide a novel strategy for the radiosensitization of keloids.

MicroRNA-613 Enhances Nasopharyngeal Carcinoma Cell Radiosensitivity via the DNA Methyltransferase 3B/Tissue Inhibitor of Matrix Metalloproteinase-3/Signal Transducer and Activator of Transcription-1/Forkhead Box O-1 Axis

Nasopharyngeal carcinoma (NPC) is a common malignancy of the nasopharynx, and radioresistant represents the main obstacle in NPC treatment. Malignant transformation of normal cells is driven by genetic and epigenetic changes, which are primarily manifested as changes in miRNA levels and DNA methylation status. microRNA (miR)-613 plays an inhibitory role in several types of cancer. Herein, the current study sought to explore the roles of miR-613 in NPC cell radiosensitivity. miR-613 expression patterns in NPC tissues were detected, and its correlation with clinical indexes was analyzed. NP-69 and C666-1 cell lines were selected for cellular experimentation. Radioresistant cell line C666-1R was obtained by fractionated radiation. Cell viability, survival fraction, and apoptosis were detected by CCK-8, colony formation assay, and flow cytometry. The binding relation between miR-613 and DNMT3B was verified by dual-luciferase and RIP assays. miR-613 was lowly expressed in NPC tissues and cells, with lower expression levels in C666-1R than C666-1, and further correlated with lymph node metastasis, tumor size, and tumor metastasis. miR-613 overexpression reduced C666-1R cell viability and survival fraction and increased apoptosis, while C666-1 cells with silencing miR-613 presented the opposite trends. miR-613 targeted DNMT3B. miR-613 and DNMT3B overexpression led to enhanced C666-1R cell viability and survival fraction and decreased apoptosis. miR-613 reduced TIMP3 methylation and elevated TIMP3 protein level by inhibiting DNMT3B. miR-613 enhanced NPC radiosensitivity by inhibiting the DNMT3B/TIMP3/STAT1/FOXO1 pathway. Collectively, miR-613 inhibited DNMT3B, reduced TIMP3 methylation, and increased TIMP3 protein level, thus inhibiting the STAT1/FOXO1 pathway and enhancing the radiosensitivity of NPC cells.

Integrated analysis of single-cell RNA-seq dataset and bulk RNA-seq dataset constructs a prognostic model for predicting survival in human glioblastoma

BACKGROUND

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. For patients with GBM, the median overall survival (OS) is 14.6 months and the 5-year survival rate is 7.2%. It is imperative to develop a reliable model to predict the survival probability in new GBM patients. To date, most prognostic models for predicting survival in GBM were constructed based on bulk RNA-seq dataset, which failed to accurately reflect the difference between tumor cores and peripheral regions, and thus show low predictive capability. An effective prognostic model is desperately needed in clinical practice.

METHODS

We studied single-cell RNA-seq dataset and The Cancer Genome Atlas-glioblastoma multiforme (TCGA-GBM) dataset to identify differentially expressed genes (DEGs) that impact the OS of GBM patients. We then applied the least absolute shrinkage and selection operator (LASSO) Cox penalized regression analysis to determine the optimal genes to be included in our risk score prognostic model. Then, we used another dataset to test the accuracy of our risk score prognostic model.

RESULTS

We identified 2128 DEGs from the single-cell RNA-seq dataset and 6461 DEGs from the bulk RNA-seq dataset. In addition, 896 DEGs associated with the OS of GBM patients were obtained. Five of these genes (LITAF, MTHFD2, NRXN3, OSMR, and RUFY2) were selected to generate a risk score prognostic model. Using training and validation datasets, we found that patients in the low-risk group showed better OS than those in the high-risk group. We validated our risk score model with the training and validating datasets and demonstrated that it can effectively predict the OS of GBM patients.

CONCLUSION

We constructed a novel prognostic model to predict survival in GBM patients by integrating a scRNA-seq dataset and a bulk RNA-seq dataset. Our findings may advance the development of new therapeutic targets and improve clinical outcomes for GBM patients.

RSL3 Drives Ferroptosis through NF-κB Pathway Activation and GPX4 Depletion in Glioblastoma

Glioblastoma, the most aggressive form of malignant glioma, is very difficult to treat because of its aggressively invasive nature and high recurrence rates. RAS-selective lethal 3 (RSL3), a well-known inhibitor of glutathione peroxidase 4 (GPX4), could effectively induce oxidative cell death in glioblastoma cells through ferroptosis, and several signaling pathways are involved in this process. However, the role of the nuclear factor kappa-B (NF-κB) pathway in glioblastoma cell ferroptosis has not yet been investigated. Therefore, we aimed to clarify the underlying mechanism of the NF-κB pathway in RSL3-induced ferroptosis in glioblastoma cells. We found that RSL3 led to an increase in lipid ROS concentration and downregulation of ferroptosis-related proteins such as GPX4, ATF4, and SLC7A11 (xCT) in glioblastoma cells. Additionally, the NF-κB pathway was activated by RSL3, and its inhibition by BAY 11-7082 could alleviate ferroptosis. The murine xenograft tumor model indicated that NF-κB pathway inhibition could mitigate the antitumor effects of RSL3 in vivo. Furthermore, we found that GPX4 knockdown could not effectively induce ferroptosis. However, NF-κB pathway activation coupled with GPX4 silencing induced ferroptosis. Additionally, ATF4 and xCT expression might be regulated by the NF-κB pathway. Collectively, our results revealed that the NF-κB pathway plays a novel role in RSL3-induced ferroptosis in glioblastoma cells and provides a new therapeutic strategy for glioblastoma treatment.

A System Bioinformatics Approach Predicts the Molecular Mechanism Underlying the Course of Action of Radix Salviae Reverses GBM Effects

Objective

This study used in vitro techniques to investigate the therapeutic effect of Radix Salviae on human glioblastoma and decode its underlying molecular mechanism.

Methods

The active components and targets of the Radix Salviae were identified from the Traditional Chinese Medicine Systems Pharmacology Database (TCMSP). The targets of human glioblastoma were obtained from the GeneCards Database. The Radix Salviae-mediated antiglioblastoma was evaluated by Gene Ontology (GO) analyses and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. Finally, mechanism of action of Radix Salviae against human glioblastoma was deduced by molecular docking and experiments.

Results

We screened 66 active ingredients and 45 targets of the Radix Salviae. The enrichment analysis based on the targets mentioned above suggested a possible role in protein phosphorylation, cell transcription, apoptosis, and inflammatory factor signaling pathways. Further study demonstrated that cryptotanshinone, an essential component of Radix Salviae, played a significant role in killing human glioblastoma cells and protecting the body by inhibiting the AKT, IKB, and STAT3 signaling pathways.

Conclusions

Radix Salviae could inhibit the proliferation and invasion of human glioblastoma by regulating STAT3, Akt, and IKB signaling pathways. Radix Salviae has potential therapeutic value in the future for human glioblastoma.

Identification of Biomarkers for Cervical Cancer Radiotherapy Resistance Based on RNA Sequencing Data

Cervical cancer as a common gynecological malignancy threatens the health and lives of women. Resistance to radiotherapy is the primary cause of treatment failure and is mainly related to difference in the inherent vulnerability of tumors after radiotherapy. Here, we investigated signature genes associated with poor response to radiotherapy by analyzing an independent cervical cancer dataset from the Gene Expression Omnibus, including pre-irradiation and mid-irradiation information. A total of 316 differentially expressed genes were significantly identified. The correlations between these genes were investigated through the Pearson correlation analysis. Subsequently, random forest model was used in determining cancer-related genes, and all genes were ranked by random forest scoring. The top 30 candidate genes were selected for uncovering their biological functions. Functional enrichment analysis revealed that the biological functions chiefly enriched in tumor immune responses, such as cellular defense response, negative regulation of immune system process, T cell activation, neutrophil activation involved in immune response, regulation of antigen processing and presentation, and peptidyl-tyrosine autophosphorylation. Finally, the top 30 genes were screened and analyzed through literature verification. After validation, 10 genes (KLRK1, LCK, KIF20A, CD247, FASLG, CD163, ZAP70, CD8B, ZNF683, and F10) were to our objective. Overall, the present research confirmed that integrated bioinformatics methods can contribute to the understanding of the molecular mechanisms and potential therapeutic targets underlying radiotherapy resistance in cervical cancer.

Identification of Key Genes Mutations Associated With the Radiosensitivity by Whole Exome Sequencing in Pancreatic Cancer

BACKGROUND

Pancreatic cancer (PC) is one of the most lethal human cancers, and radiation therapy (RT) is an important treating option. Many patients diagnosed with PC do not achieve objective responses because of the existence of intrinsic and acquired radioresistance. Therefore, biomarkers, which predict radiotherapy benefit in PC, are eagerly needed to be identified.

METHODS

Whole-exome sequencing of six pancreatic ductal adenocarcinoma patients (PDAC) (three with a good response and three with a poor response) who had received radical surgery and then radiotherapy has been performed as standard of care treatment. Somatic and germline variants and the mutational signatures were analyzed with bioinformatics tools and public databases. Functional enrichment and pathway-based protein-protein interaction analyses were utilized to address the possibly mechanism in radioresistance. MTT, LDH, and colony formation assay were applied to evaluate cell growth and colony formation ability.

RESULTS

In the present study, somatic mutations located in 441 genes were detected to be radiosensitivity-related loci. Seventeen genes, including the Smad protein family members (SMAD3 and SMAD4), were identified to influence the radiosensitivity in PDAC. The SMAD3 and SMAD4 genes mutate differently between radiosensitive and radioresistant PDAC patients. Mutation of SMAD3 potentiates the effects of ionizing radiation (IR) on cell growth and colony formation in PDAC cells, whereas mutation of SMAD4 had the opposite effects. SMAD3 and SMAD4 regulate the radiosensitivity of PDAC, at least in part, by P21 and FOXO3a, respectively.

CONCLUSIONS

These results indicate that mutations of SMAD3 and SMAD4 likely cause the difference of response to radiotherapy in PDAC, which might be considered as the biomarkers and potential targets for the radiotherapy of pancreatic cancer.

LncRNA SNHG16 Regulates the Progress of Acute Myeloid Leukemia Through miR183-5p-FOXO1 Axis

Purpose

At present, there is a lack of precise knowledge on acute myeloid leukemia (AML) at the molecular level, and understanding its occurrence at the genetic level is conducive to the development of targeted therapies. Therefore, in this study the relationship between the lncRNA SNHG1 –miR183-5p–FOXO1 axis and AML was explored.

Methods

Expression of lncRNA SNHG16 and miR183-5p was quantified by quantitative real-time PCR, and the level of FOXO1 and other proteins was measured by Western blot. Expression vectors of lncRNA SNHG16, miR183-5p, and FOXO1 were constructed to assess effects of the three on cell proliferation and apoptosis. MTT reduction assays were employed for cell proliferation, flow cytometry for cell cycle and apoptosis, and dual luciferase–reporter assays for the targeting relationship between lncRNA SNHG16 and miR183-5p and miR183-5p and FOXO1.

Results

lncRNA SNHG16 was highly expressed in peripheral blood/leukemia cell lines of patients with AML compared with normal human peripheral blood/peripheral blood mononuclear cells. miR183-5p was the target of lncRNA SNHG16 and FOXO1 the target gene of miR183-5p rather than lncRNA SNHG16. Absence of lncRNA SNHG16 led to upregulation of miR183-5p, promotion of apoptosis, and inhibition of proliferation. Suppression of miR183-5p accelerated cell proliferation and hindered apoptosis. miR183-5p negatively regulated FOXO1, and FOXO1 promoted proliferation and inhibited apoptosis. Inhibition of miR183-5p counteracted the changes caused by lncRNA SNHG16 absence.

Conclusion

lncRNA SNHG16 regulates the progress of AML via the miR183-5p–FOXO1 axis.

Dihydroartemisinin initiates ferroptosis in glioblastoma through GPX4 inhibition

It has been demonstrated from previous studies about the killing effect of dihydroartemisinin (DHA) on glioblastoma, which involves multiple aspects: cytotoxicity, cell cycle arrest and invasion inhibition. DHA has the advantages of low cytotoxicity to normal cells, selective killing effect and low drug resistance, making it one of the popular anti-tumor research directions. Ferroptosis is a newly discovered form of cell death characterized by iron dependence and lipid reactive oxygen species (ROS) accumulation. In the present study, we found differences in the expression of transferrin receptors in normal human astrocytes (NHA) and glioblastoma cells (U87 and A172), which may be one of the mechanisms of DHA selective killing effect. Through the determination of ferroptosis-related protein expression, we found that the significant decrease of GPX4, accompanied by the constant expression of xCT and ACSL4, suggesting GPX4 was a pivotal target for DHA-activated ferroptosis in glioblastoma. Total and lipid ROS levels were increased and all these results could be reversed by the ferroptosis inhibitor, ferrostatin-1. These findings demonstrated ferroptosis would be a critical component of cell death caused by DHA and GPX4 was the main target. All these results provide a novel treatment direction to glioblastoma. The association between ferroptosis and polyamines is also discussed, which will provide new research directions for ferroptosis caused by DHA in glioblastoma.

Propofol inhibits proliferation and cisplatin resistance in ovarian cancer cells through regulating the microRNA‑374a/forkhead box O1 signaling axis

Ovarian cancer is a prominent disease that demonstrates high incidence rates in women and often presents multidrug resistance. Propofol has been demonstrated to suppress the malignancy of various types of human cancer; however, the underlying molecular mechanisms of propofol in ovarian cancer remain largely unknown. The present study aimed to investigate whether and how propofol inhibits proliferation and cisplatin (DDP) resistance in ovarian cancer cells. Ovarian cancer cell viability was assessed by the Cell Counting kit-8 assay; apoptosis and cell cycle progression were determined by flow cytometry; the relative expression levels of microRNA (miR)-374a and forkhead box O1 (FOXO1) were analyzed using reverse transcription-quantitative PCR; the binding ability of miR-374a to FOXO1 was assessed by the dual-luciferase reporter assay; cellular sensitivity to DDP was detected using the MTT assay; and finally, the protein expression levels of FOXO1, p27, and Bcl-2-like-protein 11 (Bim) were analyzed by western blotting. Propofol reduced viability, promoted apoptosis and decreased miR-374a expression levels in A2780 cells. In addition, the viability of A2780/DDP cells in the propofol + DDP treatment group was significantly inhibited, and the apoptotic rate was increased. In addition, miR-374a overexpression increased cell viability and the proportion of cells in the S phase, and decreased the proportion of cells in the G0/G1 phase. Conversely, genetic knockdown of miR-374a exerted the opposite effects on cell viability and cell cycle progression. Moreover, miR-374a was demonstrated to bind to FOXO1. Propofol promoted the expression of FOXO1, p27 and Bim, induced cell cycle arrest and decreased ovarian cancer cell viability. In addition, treatment with propofol and DDP regulated FOXO1 and increased apoptosis of ovarian cancer cells. In conclusion, propofol downregulated miR-374a and modulated the FOXO1 pathway to reduce proliferation and DDP resistance in ovarian cancer cells.