Intermittent Hypoxia Mediates Cancer Development and Progression Through HIF-1 and miRNA Regulation

Exploring the pharmacological mechanisms for alleviating OSA: Adenosine A2A receptor downregulation of the PI3K/Akt/HIF‑1 pathway (Review)

Obstructive sleep apnea (OSA) is the most common type of sleep apnea, which leads to episodes of intermittent hypoxia due to obstruction of the upper airway. A key feature of OSA is the upregulation and stabilization of hypoxia-inducible factor 1 (HIF-1), a crucial metabolic regulator that facilitates rapid adaptation to changes in oxygen availability. Adenosine A2A receptor (A2AR), a major adenosine receptor, regulates HIF-1 under hypoxic conditions, exerting anti-inflammatory properties and affecting lipid metabolism. The present study explored the roles of A2AR in OSA regulation, specifically focusing on its effects via the PI3K/Akt/HIF-1 pathway. The findings enhance our understanding the pharmacological potential of A2AR in OSA management and suggest future research directions in exploring its clinical applications.

MiRNA expression affects survival in patients with obstructive sleep apnea and metastatic colorectal cancer

Introduction

The relationship between obstructive sleep apnea (OSA) and cancer has been recognized for some time now. However, little is known about the mechanisms by which sleep apnea promotes tumorigenesis and the impact of OSA on survival after cancer diagnosis. In the last few years, research has focused on the exploration of different biomarkers to understand the mechanisms underlying this relationship and miRNAs, non-coding single strands of about 22 nucleotides that post-transcriptionally regulate gene expression, have emerged as possible actors of this process.The aim of the study was to evaluate the impact of OSA on survival of metastatic colorectal cancer (mCRC) patients based on the expression of specific miRNAs.

Methods

The expression of 6 miRNAs, respectively miR-21, miR-23b, miR-26a, miR-27b, miR-145 and miR-210, was analyzed by qRT-PCR in patients' sera. Response to first-line therapy, Kaplan-Meier curves of overall and progression-free survival were used to evaluate survival in mCRC patients with and without OSA stratified for the expression of miRNAs.

Results

The expression of miR-21, miR-23b, miR-26a and miR-210 was significantly upregulated in mCRCs with OSA compared to no OSA. In mCRC patients with OSA and increasing expression of miR-21, miR-23b, miR-26a and miR-210 risk of progression after first-line therapy was higher and both overall and progression-free survival were significantly worst. Conversely, as miR-27b and miR-145 expression increased, the life expectancy of patients diagnosed with OSA and mCRC improved markedly.

Conclusions

This study highlights the relevance of specific miRNAs on OSA in mCRCs and their significance as non-invasive biomarkers in predicting the prognosis in patients with mCRC and OSA.

HYPOXIA induces lncRNA HOTAIR for recruiting RELA in papillary thyroid cancer cells to upregulate miR-181a and promote angiogenesis

BACKGROUND

Papillary thyroid carcinoma (PTC) is one of the most common subtypes of thyroid carcinoma. Exosomal miR-181a plays an important role in the development of PTC. This study examined the regulatory mechanism of miR-181a under conditions of hypoxia and its impact on angiogenesis.

METHODS

A ribonucleoprotein immunoprecipitation (RIP) experiment was conducted to verify the interaction between HOTAIR and RELA. The relationship between RELA and the miR-181a promoter was detected by ChIP-qPCR. Short hairpin (sh) RNA was designed to knock down HOTAIR in TPC cells. The underlying mechanism of miR-181a was verified by use of dual-luciferase assays and rescue experiments. The regulatory effect of GATA6 on angiogenesis was studied using CCK8, EdU, Transwell, and western blot assays.

RESULTS

A RIP assay showed that HOTAIR could bind to RELA under hypoxic conditions. ChIP-qPCR and dual luciferase assays showed RELA could interact with the miR181a promoter and upregulate miR-181a. Knockdown of HOTAIR downregulated miR-181a in TPC-1 cells, and the downregulation could be rescued by RELA overexpression. MiR-181a downregulated GATA6 in HUVEC cells. Overexpression of GATA6 inhibited HUVEC proliferation, migration, tube formation, and EGFR expression. Exosomal miR-181a promoted angiogenesis by downregulating GATA6 expression.

CONCLUSION

HOTAIR activated RELA to upregulate miR-181a during hypoxia. Exosomal miR-181a promotes tumor angiogenesis by downregulating GATA6.

Treatment of obstructive sleep apnea with CPAP improves daytime sleepiness and fatigue in cancer patients

BACKGROUND

Fatigue and sleep disorders are prevalent in cancer patients. Obstructive sleep apnea (OSA) commonly causes excessive daytime sleepiness (EDS) and fatigue. We hypothesize that treating cancer patients with OSA using positive airway pressure (PAP) will improve EDS and fatigue.

METHODS

A retrospective chart review of sleep clinic visits of cancer patients with newly diagnosed OSA was performed. Epworth Sleepiness Scale (ESS) and fatigue reported at baseline and within 6 months of starting PAP therapy were compared between PAP-adherent and PAP-non-adherent patients.

RESULTS

65 cancer patients with OSA and ESS >10 were recommended PAP therapy, including 45 patients with fatigue. 29 patients pursued PAP therapy with 79% (n = 23) adherent at follow-up. The median baseline apnea hypopnea index (AHI) for OSA was 24.0 (interquartile range [IQR] 14.3, 32.3) and 23.8 (IQR 10.1, 42.8) events/hour among PAP-adherent and PAP-non-adherent patients, respectively (p = 0.90). Median baseline ESS was 14.0 (IQR 12.0, 17.0) among adherent and 17.0 (IQR 11.0, 17.3) among non-adherent patients (p = 0.73). The median ESS at follow-up of the adherent and non-adherent groups was 8.0 (IQR 6.0, 10.0) and 11.0 (IQR 8.0, 15.8), respectively (p = 0.08). Median ESS change was -5.0 (IQR -7.0, -4.0) in PAP adherent patients and -2.5 (IQR -5.25, -1.50) in PAP-non-adherent patients (p = 0.07). When the groups are examined separately, the median change in the PAP-adherent group was highly significant (p = 0.001), while the ESS median change in the PAP-non-adherent group was considerably less (p = 0.04). 17 out of the 21 PAP-adherent patients reporting fatigue at baseline indicated improvement at follow-up.

CONCLUSIONS

PAP therapy for OSA in cancer patients improves EDS and fatigue. Larger studies are necessary to evaluate the efficacy of PAP in improving fatigue in this population.

Regulation of Cancer-Associated miRNAs Expression under Hypoxic Conditions

Solid tumors frequently experience hypoxia or low O2 levels. In these conditions, hypoxia-inducible factor 1 alpha (HIF-1α) is activated and acts as a transcription factor that regulates cancer cell adaptation to O2 and nutrient deprivation. HIF-1α controls gene expression associated with various signaling pathways that promote cancer cell proliferation and survival. MicroRNAs (miRNAs) are 22-nucleotide noncoding RNAs that play a role in various biological processes essential for cancer progression. This review presents an overview of how hypoxia regulates the expression of multiple miRNAs in the progression of cancer cells.

Predictors of moderate to severe obstructive sleep apnea in patients with lung cancer

BACKGROUND AND OBJECTIVES

OSA is a known medical condition that is associated with several comorbidities and affect patients' quality of life. The association between OSA and lung cancer remains debated. Some studies reported increased prevalence of OSA in patients with lung cancer. We aimed to assess predictors of moderate-to-severe OSA in patients with lung cancer.

METHODS

We enrolled 153 adult patients who were newly diagnosed with lung cancer. Cardiorespiratory monitoring was performed using home sleep apnea device. We carried out Univariate and multivariate logistic regression analysis on multiple parameters including age, gender, smoking status, neck circumference, waist circumference, BMI, stage and histopathology of lung cancer, presence of superior vena cava obstruction, and performance status to find out the factors that are independently associated with a diagnosis of moderate-to-severe OSA.

RESULTS

Our results suggest that poor performance status is the most significant predictor of moderate to severe OSA in patients with lung cancer after controlling for important confounders.

CONCLUSION

Performance status is a predictor of moderate to severe OSA in patients with lung cancer in our population of middle eastern ethnicity.

Investigation of Common Pathways and Putative Biomarker Candidates of Colorectal Cancer and Insomnia by Using Integrative In-Silico Approaches

Background

Colorectal cancer (CRC) is one of the leading causes of cancer-related mortalities across the globe. Accumulating evidence shows that individuals having sleep disorders such as insomnia are at high risk of developing CRC, yet the association of sleep disorders with CRC risk is still unclear. Here, we investigated the potential molecular connections between CRC and insomnia using integrative in silico approaches.

Objective

This study aims to explore the potential molecular connections between CRC and insomnia utilizing integrative in-silico methodologies.

Methods and Methods

Gene expression microarray datasets for CRC and insomnia samples were retrieved from the NCBI-GEO database and analyzed using R. Functional enrichment analysis of common differentially expressed genes (DEGs) was performed by the g: Profiler tool. Cytoscape software was used to construct a protein-protein interaction network and hub gene identification. Expression profiles of hub genes in TCGA datasets were also determined, and predicted miRNAs targeting hub genes were analyzed by miRNA target prediction tools.

Results

Our results revealed a total of 113 shared DEGs between the CRC and insomnia datasets. Six genes (HSP8A, GAPDH, HSP90AA1, EEF1G, RPS6, and RPLP0), which were also differently expressed in TCGA datasets, were prioritized as hub genes and were found to be enriched in pathways related to protein synthesis. hsa-miR-324-3p, hsa-miR-769-3p, and hsa-miR-16-5p were identified as promising miRNA biomarkers for two diseases.

Conclusions

Our in-silico analysis provides promising evidence of the molecular link between CRC and insomnia and highlights multiple potential molecular biomarkers and pathways. Validation of the results by wet lab work can be utilized for novel translational and precision medicine applications to alleviate the public health burden of CRC.

Dysregulation in CD39/CD73 Axis May Trigger the Upsurge of the Immune Suppressive Agent Adenosine in OSA Patients

INTRODUCTION

Although higher incidence of cancer represents a major burden for obstructive sleep apnea (OSA) patients, the molecular pathways driving this association are not completely understood. Interestingly, adenosinergic signaling has emerged as a powerful immune checkpoint driving tumor development and progression.

METHODS

Here, we explored the expression of the adenosinergic ecto-enzymes CD39 and CD73 in T-lymphocytes of OSA patients without any evidence of cancer, as well as their soluble forms in plasma (sCD39 and sCD73), along with adenosine. In addition, we explored the role of intermittent hypoxia (IH) in this context by in vitro models.

RESULTS

Our results showed that CD39 is upregulated while CD73 is downregulated in OSA T-cells' membrane. Moreover, our findings suggest that IH, through HIF-1, mediates the upregulation of both CD39 and CD73; and that CD73 downregulation could be mediated by a higher release of sCD73 by OSA T-lymphocytes. Importantly, we found that both sCD39 and sCD73 are upregulated in OSA plasma, suggesting T-lymphocytes as a potential source for plasmatic sCD73. Finally, our data propose the alterations in CD39/CD73 axis could underlie the upsurge of adenosine levels in the plasma of OSA patients.

CONCLUSION

Our study reveals a hypoxia-mediated alteration of the CD39/CD73 axis in OSA patients, which could trigger ADO upregulation, thus potentially contributing to the immune suppressive environment and ultimately facilitating tumor development and progression. Therefore, our data highlights the need for new longitudinal studies evaluating CD39 and/or CD73 as potential cancer-risk prognostic biomarkers in OSA patients.

Hypoxia preconditioning of adipose stem cell-derived exosomes loaded in gelatin methacryloyl (GelMA) promote type H angiogenesis and osteoporotic fracture repair

The challenges posed by delayed atrophic healing and nonunion stand as formidable obstacles in osteoporotic fracture treatment. The processes of type H angiogenesis and osteogenesis emerge as pivotal mechanisms during bone regeneration. Notably, the preconditioning of adipose-derived stem cell (ADSC) exosomes under hypoxic conditions has garnered attention for its potential to augment the secretion and functionality of these exosomes. In the present investigation, we embarked upon a comprehensive elucidation of the underlying mechanisms of hypo-ADSC-Exos within the milieu of osteoporotic bone regeneration. Our findings revealed that hypo-ADSC-Exos harboured a preeminent miRNA, namely, miR-21-5p, which emerged as the principal orchestrator of angiogenic effects. Through in vitro experiments, we demonstrated the capacity of hypo-ADSC-Exos to stimulate the proliferation, migration, and angiogenic potential of human umbilical vein endothelial cells (HUVECs) via the mediation of miR-21-5p. The inhibition of miR-21-5p effectively attenuated the proangiogenic effects mediated by hypo-ADSC-Exos. Mechanistically, our investigation revealed that exosomal miR-21-5p emanating from hypo-ADSCs exerts its regulatory influence by targeting sprouly1 (SPRY1) within HUVECs, thereby facilitating the activation of the PI3K/AKT signalling pathway. Notably, knockdown of SPRY1 in HUVECs was found to potentiate PI3K/AKT activation and, concomitantly, HUVEC proliferation, migration, and angiogenesis. The culminating stage of our study involved a compelling in vivo demonstration wherein GelMA loaded with hypo-ADSC-Exos was validated to substantially enhance local type H angiogenesis and concomitant bone regeneration. This enhancement was unequivocally attributed to the exosomal modulation of SPRY1. In summary, our investigation offers a pioneering perspective on the potential utility of hypo-ADSC-Exos as readily available for osteoporotic fracture treatment.

The dual role of MiR-210 in the aetiology of cancer: A focus on hypoxia-inducible factor signalling

Tumorigenesis exemplifies the complex process of neoplasm origination, which is characterised by somatic genetic alterations and abnormal cellular growth. This multidimensional phenomenon transforms previously dormant cells into malignant equivalents, resulting in uncontrollable proliferation and clonal expansion. Various elements, including random mutations, harmful environmental substances, and genetic predispositions, influence tumorigenesis's aetiology. MicroRNAs (miRNAs) are now recognised as crucial determinants of gene expression and key players in several biological methods, including oncogenesis. A well-known hypoxia-inducible miRNA is MiR-210, which is of particular interest because of its complicated role in the aetiology of cancer and a variation of physiological and pathological situations. MiR-210 significantly impacts cancer by controlling the hypoxia-inducible factor (HIF) signalling pathway. By supporting angiogenesis, metabolic reprogramming, and cellular survival in hypoxic microenvironments, HIF signalling orchestrates adaptive responses, accelerating the unstoppable development of tumorous growth. Targeting several components of this cascade, including HIF-1, HIF-3, and FIH-1, MiR-210 plays a vital role in modifying HIF signalling and carefully controlling the HIF-mediated response and cellular fates in hypoxic environments. To understand the complexities of this relationship, careful investigation is required at the intersection of MiR-210 and HIF signalling. Understanding this relationship is crucial for uncovering the mechanisms underlying cancer aetiology and developing cutting-edge therapeutic approaches. The current review emphasises MiR-210's significance as a vital regulator of the HIF signalling cascade, with substantial implications spanning a range of tumor pathogenesis.

Intermittent Hypoxia Promotes TAM-Induced Glycolysis in Laryngeal Cancer Cells via Regulation of HK1 Expression through Activation of ZBTB10

Obstructive sleep apnea (OSA), characterized by intermittent hypoxia (IH), may increase the risk of cancer development and a poor cancer prognosis. TAMs of the M2 phenotype, together with the intermittent hypoxic environment within the tumor, drive tumor aggressiveness. However, the mechanism of TAMs in IH remains unclear. In our study, IH induced the recruitment of macrophages, and IH-induced M2-like TAMs promoted glycolysis in laryngeal cancer cells through hexokinase 1. The hexokinase inhibitor 2-deoxy-D-glucose and HK1 shRNA were applied to verify this finding, confirming that M2-like TAMs enhanced glycolysis in laryngeal cancer cells through HK1 under intermittent hypoxic conditions. Comprehensive RNA-seq analysis disclosed a marked elevation in the expression levels of the transcription factor ZBTB10, while evaluation of a laryngeal cancer patient tissue microarray demonstrated a positive correlation between ZBTB10 and HK1 expression in laryngeal carcinoma. Knockdown of ZBTB10 decreased HK1 expression, and overexpression of ZBTB10 increased HK1 expression in both laryngeal cancer cells and 293T cells. The luciferase reporter assay and Chromatin immunoprecipitation assay confirmed that ZBTB10 directly bound to the promoter region of HK1 and regulated the transcriptional activity of HK1. Finally, the CLEC3B level of the M2 supernatant is significantly higher in the IH group and showed a protumor effect on Hep2 cells. As ZBTB10-mediated regulation of HK1 affects glycolysis in laryngeal cancer, our findings may provide new potential therapeutic targets for laryngeal cancer.