The role of cellular senescence and SASP in tumour microenvironment

Emerging prodrug and nano-drug delivery strategies for the detection and elimination of senescent tumor cells

Tumor cellular senescence, characterized by reversible cell cycle arrest following anti-cancer therapies, presents a complex paradigm in oncology. Given that senescent tumor cells may promote angiogenesis, tumorigenesis, and metastasis, selective killing senescent cells (SCs)-a strategy termed senotherapy-has emerged as a promising approach to improve cancer treatment. However, the clinical implementation of senotherapy faces significant hurdles, including lack of precise methods for SCs identification and the potential for adverse effects associated with highly cytotoxic senolytic agents. In this account, we elucidate recent advancement in developing novel approaches for the detection and selective elimination of SCs, encompassing prodrugs, nanoparticles, and other cutting-edge drug delivery systems such as PROTAC technology and CAR T cell therapy. Furthermore, we explore the paradoxical nature of SCs, which can induce growth arrest in adjacent neoplastic cells and recruit immunomodulatory cells that contribute to tumor suppression. Therefore, we utilize SCs membrane as vehicles to elicit antitumor immunity and potentially augment existing anti-cancer therapies. Finally, the opportunities and challenges are put forward to facilitate the development and clinical transformation of SCs detection, elimination or utilization.

USP14/S100A11 axis promote colorectal cancer progression by inhibiting cell senescence

The aberrant expression of S100A11 has been identified in various malignancies but its functional roles and underlying mechanisms in colorectal cancer (CRC) have not been fully elucidated. Therefore, this study was designed to investigate the expression of S100A11 and its functional significance in CRC, indicating that S100A11 is significantly upregulated and correlates with poor survival outcomes in CRC. Functionally, S100A11 knockdown in CRC cell lines inhibited cell proliferation, invasion, and migration, leading to decreased tumour growth and metastasis in vivo. Mechanistic investigations revealed that S100A11 promotes cell proliferation and invasion by suppressing cell senescence. In addition, USP14 interacts with and mediates S100A11 deubiquitination. More importantly, the overexpression of S100A11 was able to partially counteract the reduction in cell proliferation caused by the knockdown of USP14. In summary, the novel regulatory axis involving USP14 and S100A11 modulates the malignant biological behavior of CRC cells through inhibiting cell senescence, therefore the interaction between USP14 and S100A11 represents a promising therapeutic target in CRC.

Sciellin inhibits senescence and promotes pancreatic cancer progress by activating the notch signaling pathway

Pancreatic cancer (PC) incidence is increasing annually globally, and the five-year survival rate of patients with PC is approximately 10%. Cellular senescence is a regulatory mechanism against cancer that prevents tumor development by inhibiting the proliferation of damaged or abnormal cells. However, the mechanisms underlying cellular senescence in PC is unclear. Sciellin (SCEL) is a precursor protein of the cornified envelope predominantly enriched in epithelial cells. Previous studies have discovered potential links between SCEL and cellular senescence through bioinformatics analysis. Therefore, the specific role of SCEL in cellular senescence and the malignant features of PC are unclear. In vivo and in vitro assays were performed to investigate the role of SCEL in PC cell senescence, proliferation, invasion, and metastasis. Gene set enrichment analysis was used to identify the Notch signaling pathways activated by SCEL, and coimmunoprecipitation was used to detect proteins that interact with SCEL. The results revealed that SCEL was significantly upregulated in PC tissues and cell models and was correlated with poor clinical outcomes. Further investigation revealed that the interaction between SCEL and Jagged-1 promotes the activation of the Notch signaling pathway, effectively inhibiting the senescence of PC cells while enhancing their proliferation, invasion, and metastatic capabilities. Therefore, SCEL is a potential therapeutic target for PC.

p21-Dependent Senescence Induction by BMP4 Renders Glioblastoma Cells Vulnerable to Senolytics

Glioblastoma (GBM) is a highly malignant brain tumor with extensive cellular heterogeneity and plasticity. Bone morphogenetic protein 4 (BMP4) has shown potential as a therapeutic agent by promoting differentiation, but its effects are complex and context dependent. While BMP4's role in differentiation is well established, its impact on senescence remains unclear. This study investigates BMP4's ability to induce senescence in GBM cells. Primary GBM cultures were treated with BMP4 and analyzed for senescence markers, including cell enlargement, p21 expression, senescence-related gene enrichment, and senescence-associated-β-galactosidase activity. A p21 knockout model was used to determine its role in BMP4-induced senescence, and sensitivity to the senolytic agent navitoclax was evaluated. BMP4 induced senescence in the GBM cultures, particularly in mesenchymal (MES)-like GBM cells with high baseline p21 levels. The knockout of p21 nearly abolished BMP4-induced senescence, maintaining cell size and proliferation. Furthermore, navitoclax effectively eliminated BMP4-induced senescent cells through apoptosis, while sparing cells with normal p21 expression. Our findings highlight BMP4 as an inducer of p21-dependent senescence in GBM, particularly in MES-like cells. This study clarifies BMP4's dual roles in differentiation and senescence, emphasizing their context dependence. Given the strong link between MES-like cells and therapy resistance, their heightened susceptibility to senescence may aid in developing targeted therapies for GBM and potentially other cancers with similar cellular dynamics.

A bifunctional fusion membrane-based biocompatible nanovaccine to potentiate cancer immunotherapy

Background: Cancer cell membrane-based nanovaccines derived from patients' tumor tissues have shown promising features as a personalized cancer treatment strategy. However, the weak immunogenicity of autologous tumor antigens undermines the therapeutic effects of personalized vaccines. Methods: We synthesized a biomimetic nanovaccine, Bio-HCP@FM-NPs, composed of senescent tumor cell membranes, Escherichia coli cytoplasmic membrane extracts, and granulocyte-macrophage colony-stimulating factor (GM-CSF)-encapsulated biocompatible hypercross-linked polymer nanoparticles. The nanovaccine's antitumor and enhanced immunotherapy effects were demonstrated in multiple tumor models. The tumor prevention effects of nanovaccine were assessed using a postoperative recurrence model. Results: The Bio-FM@HCP-NP vaccine showed promising therapeutic efficacy in the B16-F10 melanoma mouse model and significantly synergized with anti-PD-1 immunotherapy across multiple tumor models. Mechanistically, GM-CSF was promptly released to recruit naïve DCs to the nanovaccine. Thereafter, immature DCs were vigorously activated by FM-NPs, thereby activating the cytotoxic T cells. Furthermore, Bio-HCP@FM-NPs induced robust antigen-specific immune responses, prolonging postoperative survival in mice and providing long-term protection against tumor recurrence. Targeted depletion of immune cell populations revealed that T and B cells were essential for vaccine-induced tumor regression. Conclusion: The Bio-HCP@FM-NPs showed significant promise for immunotherapy and tailored postoperative treatment of cancer, leveraging the strong activation of innate immunity by senescent tumor cell membranes and bacterial cytoplasmic membrane extracts.

A Senescence-Associated Gene Signature for Prognostic Prediction and Therapeutic Targeting in Adrenocortical Carcinoma

Background/Objectives: Cellular senescence plays a critical role in tumorigenesis, immune cell infiltration, and treatment response. Adrenocortical carcinoma (ACC) is a malignant tumor that lacks effective therapies. This study aimed to construct and validate a senescence-related gene signature as an independent prognostic predictor for ACC and explore its impact on the tumor microenvironment, immunotherapy, and chemotherapy response. Methods: Data were collected from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) database. Using Kaplan-Meier survival analysis, LASSO penalized Cox regression and multivariable Cox regression, we identified a prognostic model with four senescence-related genes (HJURP, CDK1, FOXM1, and CHEK1). The model's prognostic value was validated through survival analysis, risk score curves, and receiver operating characteristic (ROC) curves. Tumor mutation burden was assessed with maftools, and the tumor microenvironment was analyzed using CIBERSORT and ESTIMATE. Immune and chemotherapeutic responses were assessed through Tumor Immune Dysfunction and Exclusion (TIDE) and OncoPredict. Results: The risk score derived from our model showed a strong association with overall survival (OS) in ACC patients (p < 0.001, HR = 2.478). Higher risk scores were correlated with more advanced tumor stages and a greater frequency of somatic mutations. Differentially expressed genes (DEGs) that were downregulated in the high-risk group were significantly enriched in immune-related pathways. Furthermore, high-risk patients were predicted to have reduced sensitivity to immunotherapy (p = 0.02). Bioinformatics analysis identified potential chemotherapeutic agents, including BI-2536 and MIM1, as more effective treatment options for high-risk patients. Conclusions: Our findings indicate that this prognostic model may serve as a valuable tool for predicting overall survival (OS) and treatment responses in ACC patients, including those receiving chemotherapy and immunotherapy.

The influence of senescent associated secretory phenotype on glucose homeostasis in C2C12 muscle cells: insights into potential p38 inhibitor interventions

Increased accumulation of senescent cells with aging is associated with reduced ability of insulin-target tissues to utilize glucose, resulting in increased insulin resistance and glucotoxicity. We investigated the role of the senescent-associated secretory phenotype (SASP) within C2C12, skeletal muscle cells on glucose homeostasis and if such effects could be reduced by blocking pro-inflammatory pathways. C2C12 myotubes were treated with 40% conditioned media from senescent fibroblasts. Indirect glucose uptake and glycogen content were measured. The effect of SASP on the generation of reactive oxygen species [1] and mitochondrial function was also measured. The experiments above were repeated with a p38 inhibitor. 40% SASP treatment significantly decreased glucose utilization and glycogen storage within myotubes (p < 0.0001). 40% SASP was successful in inducing oxidative stress and increased mitochondrial density, whilst reducing membrane potential following 48 h of incubation (p < 0.0001) and blocking NF-κβ, restored glucose utilization (p < 0.01) despite the presence of SASP. Co-incubation of 40% SASP with an NF-κβ inhibitor eliminates excessive ROS production and restores mitochondrial activity to levels comparable to control treatment (p < 0.0001). This study shows changes in glucose homeostasis in senescent cells is mediated through SASP, and interventions aimed at mitigating pro-inflammatory pathways can potentially improve insulin resistance.

Senolytics: charting a new course or enhancing existing anti-tumor therapies?

Cell senescence is a natural response within our organisms. Initially, it was considered an effective anti-tumor mechanism. However, it is now believed that while cell senescence initially acts as a robust barrier against tumor initiation, the subsequent accumulation of senescent cells can paradoxically promote cancer recurrence and cause damage to neighboring tissues. This intricate balance between cell proliferation and senescence plays a pivotal role in maintaining tissue homeostasis. Moreover, senescence cells secrete many bioactive molecules collectively termed the senescence-associated secretory phenotype (SASP), which can induce chronic inflammation, alter tissue architecture, and promote tumorigenesis through paracrine signaling. Among the myriads of compounds, senotherapeutic drugs have emerged as exceptionally promising candidates in anticancer treatment. Their ability to selectively target senescent cells while sparing healthy tissues represents a paradigm shift in therapeutic intervention, offering new avenues for personalized oncology medicine. Senolytics have introduced new therapeutic possibilities by enabling the targeted removal of senescent cells. As standalone agents, they can clear tumor cells in a senescent state and, when combined with chemo- or radiotherapy, eliminate residual senescent cancer cells after treatment. This dual approach allows for the intentional use of lower-dose therapies or the removal of unintended senescent cells post-treatment. Additionally, by targeting non-cancerous senescent cells, senolytics may help reduce tumor formation risk, limit recurrence, and slow disease progression. This article examines the mechanisms of cellular senescence, its role in cancer treatment, and the importance of senotherapy, with particular attention to the therapeutic potential of senolytic drugs.

Sensor-integrated gut-on-a-chip for monitoring senescence-mediated changes in the intestinal barrier

The incidence of inflammatory bowel disease among the elderly has significantly risen in recent years, posing a growing socioeconomic burden to aging societies. Moreover, non-gastrointestinal diseases, also prevalent in this demographic, have been linked to intestinal barrier dysfunction, thus highlighting the importance of investigating aged-mediated changes within the human gut. While gastrointestinal pathology often involves an impaired gut barrier, the impact of aging on the human gastrointestinal barrier function remains unclear. To explore the effect of senescence, a key hallmark of aging, on gut barrier integrity, we established and evaluated an in vitro gut-on-a-chip model tailored to investigate barrier changes by the integration of an impedance sensor. Here, a microfluidic gut-on-a-chip system containing integrated membrane-based electrode microarrays is used to non-invasively monitor epithelial barrier formation and senescence-mediated changes in barrier integrity upon treating Caco-2 cells with 0.8 μg mL-1 doxorubicin (DXR), a chemotherapeutic which induces cell cycle arrest. Results of our microfluidic human gut model reveal a DXR-mediated increase in impedance and cell hypertrophy as well as overexpression of p21, and CCL2, indicative of a senescent phenotype. Combined with the integrated electrodes, monitoring ∼57% of the cultivation area in situ and non-invasively, the developed chip-based senescent-gut model is ideally suited to study age-related malfunctions in barrier integrity.

The Common Hallmarks and Interconnected Pathways of Aging, Circadian Rhythms, and Cancer: Implications for Therapeutic Strategies

The intricate relationship between cancer, circadian rhythms, and aging is increasingly recognized as a critical factor in understanding the mechanisms underlying tumorigenesis and cancer progression. Aging is a well-established primary risk factor for cancer, while disruptions in circadian rhythms are intricately associated with the tumorigenesis and progression of various tumors. Moreover, aging itself disrupts circadian rhythms, leading to physiological changes that may accelerate cancer development. Despite these connections, the specific interplay between these processes and their collective impact on cancer remains inadequately explored in the literature. In this review, we systematically explore the physiological mechanisms of circadian rhythms and their influence on cancer development. We discuss how core circadian genes impact tumor risk and prognosis, highlighting the shared hallmarks of cancer and aging such as genomic instability, cellular senescence, and chronic inflammation. Furthermore, we examine the interplay between circadian rhythms and aging, focusing on how this crosstalk contributes to tumorigenesis, tumor proliferation, and apoptosis, as well as the impact on cellular metabolism and genomic stability. By elucidating the common pathways linking aging, circadian rhythms, and cancer, this review provides new insights into the pathophysiology of cancer and identifies potential therapeutic strategies. We propose that targeting the circadian regulation of cancer hallmarks could pave the way for novel treatments, including chronotherapy and antiaging interventions, which may offer important benefits in the clinical management of cancer.

The efferocytosis process in aging: Supporting evidence, mechanisms, and therapeutic prospects for age-related diseases

BACKGROUND

Aging is characterized by an ongoing struggle between the buildup of damage caused by a combination of external and internal factors. Aging has different effects on phagocytes, including impaired efferocytosis. A deficiency in efferocytosis can cause chronic inflammation, aging, and several other clinical disorders.

AIM OF REVIEW

Our review underscores the possible feasibility and extensive scope of employing dual targets in various age-related diseases to reduce the occurrence and progression of age-related diseases, ultimately fostering healthy aging and increasing lifespan. Key scientific concepts of review Hence, the concurrent implementation of strategies aimed at augmenting efferocytic mechanisms and anti-aging treatments has the potential to serve as a potent intervention for extending the duration of a healthy lifespan. In this review, we comprehensively discuss the concept and physiological effects of efferocytosis. Subsequently, we investigated the association between efferocytosis and the hallmarks of aging. Finally, we discuss growing evidence regarding therapeutic interventions for age-related disorders, focusing on the physiological processes of aging and efferocytosis.

From Embryogenesis to Senescence: The Role of Mammary Gland Physiology in Breast Cancer Risk

The mammary gland undergoes significant changes throughout a woman's life; from embryonic development to transformations after breastfeeding and during aging. These processes, while essential for normal breast physiology, can increase breast cancer risk when disrupted. This review explores three critical stages: embryonic development; postlactational involution; and age-related lobular involution (ARLI). We highlight key signaling pathways-Wnt, FGF, SHH, Notch, EGFR, and BMP-that guide embryonic development and discuss how their dysregulation can contribute to abnormal growth. For postlactational involution, we examine the two-phase process of cell death and tissue remodeling, showing how disruptions during this period, particularly postpartum, may foster a tumor-promoting environment. We also delve into ARLI and the role of cellular senescence in the aging mammary gland, focusing on the senescence-associated secretory phenotype (SASP) and its impact on inflammation and tissue remodeling. Understanding these processes provides new opportunities for breast cancer prevention and treatment strategies.

Exploring the link between fat-soluble vitamins and aging-associated immune system status: a literature review

The importance of vitamin D for a well-functioning immune system is becoming increasingly evident. Nevertheless, the other fat-soluble vitamins A, E and K also seem to play a central role regarding the adequate function of immune cells and to counteract excessive immune reactions and inflammatory processes. However, recognizing hidden hunger, particularly micronutrient deficiencies in vulnerable groups like the elderly, is crucial because older adults often lack sufficient micronutrients for various reasons. This review summarizes the latest findings on the immune modulating functions of fat-soluble vitamins in a physiological and pathophysiological context, provides a graphical comparison of the Recommended Daily Allowances between Deutschland, Austria, Confoederatio Helvetica (D-A-CH; eng. GSA, Germany, Switzerland, Austria), Deutsche Gesellschaft für Ernährung (DGE; eng. German Nutrition Society) and National Institutes of Health (NIH) across all age groups and, in particular, addresses the question regarding the benefits of supplementation of the respective micronutrients for the aging population of industrialized nations to strengthen the immune system. The following review highlights the importance of fat-soluble vitamins A, D, E and K which play critical roles in maintaining immune system function and, in some cases, in preventing excessive immune activation. Therefore, a better understanding of the relevance of adequate blood levels and consequently potential supplementation strategies may contribute to the prevention and management of infectious diseases as well as better overall health of the elderly.

Immune therapeutic strategies for the senescent tumor microenvironment

Senescent cells can either to promote immunosuppressive tumor microenvironment or facilitate immune surveillance. Despite the revolutionary impact of cancer immunotherapy, durable responses in solid tumors, particularly in advanced stages, remain limited. Recent studies have shed light on the influence of senescent status within the tumor microenvironment (TME) on therapy resistance and major efforts are needed to overcome these challenges. This review summarizes recent advancements in targeting cellular senescence, with a particular focus on immunomodulatory approaches on the hallmarks of cellular senescence.

Hypoxia increases methylated histones to prevent histone clipping and heterochromatin redistribution during Raf-induced senescence

Hypoxia enhances histone methylation by inhibiting oxygen- and α-ketoglutarate-dependent demethylases, resulting in increased methylated histones. This study reveals how hypoxia-induced methylation affects histone clipping and the reorganization of heterochromatin into senescence-associated heterochromatin foci (SAHF) during oncogene-induced senescence (OIS) in IMR90 human fibroblasts. Notably, using top-down proteomics, we discovered specific cleavage sites targeted by Cathepsin L (CTSL) in H3, H2B and H4 during Raf activation, identifying novel sites in H2B and H4. Hypoxia counteracts CTSL-mediated histone clipping by promoting methylation without affecting CTSL's activity. This increase in methylation under hypoxia protects against clipping, reshaping the epigenetic landscape and influencing chromatin accessibility, as shown by ATAC-seq analysis. These insights underscore the pivotal role of hypoxia-induced histone methylation in protecting chromatin from significant epigenetic shifts during cellular aging.

Cellular senescence in the tumor with a bone niche microenvironment: friend or foe?

Cellular senescence is understood to be a biological process that is defined as irreversible growth arrest and was originally recognized as a tumor-suppressive mechanism that prevents further propagation of damaged cells. More recently, cellular senescence has been shown to have a dual role in prevention and tumor promotion. Senescent cells carry a senescence-associated secretory phenotype (SASP), which is altered by secretory factors including pro-inflammatory cytokines, chemokines, and other proteases, leading to the alteration of the tissue microenvironment. Though senescence would eventually halt the growth of cancerous potential cells, SASP contributes to the tumor environment by promoting inflammation, matrix remodeling, and tumor cell invasion. The paradox of tumor prevention/promotion is particularly relevant to the bone niche tumor microenvironment, where longer-lasting, chronic inflammation promotes tumor formation. Insights into a mechanistic understanding of cellular senescence and SASP provide the basis for targeted therapies, such as senolytics, which aim to eliminate senescent cells, or SASP inhibitors, which would eliminate the tumor-promoting effects of senescence. These therapeutic interventions offer significant clinical implications for treating cancer and healthy aging.

Resolution of oncogene-induced senescence markers in HPV-infected cervical cancer tissue

BACKGROUND

Oncogene-Induced Senescence (OIS) is a form of senescence that occurs as a consequence of oncogenic overstimulation and possibly infection by oncogenic viruses. Whether senescence plays a role in the pathogenesis of cervical cancer (CC) is not well understood. Moreover, whether cervical epithelial cells that are part of the premalignant cervical intraepithelial neoplasia (CIN), exhibit markers of OIS in Human Papillomavirus (HPV)-infected tissue, has not been investigated.

METHODS

We utilized a set of patient-derived premalignant and malignant tissue samples to investigate the protein (Ki67 and Lamin B1) and gene (TP53, IL1A, CCL2, and MMP9) expression of several OIS-associated biomarkers using immunohistochemistry (IHC) and qRT-PCR, respectively. Furthermore, we characterized the HPV status of all tissue samples.

RESULTS

Most of the CC samples (34/37) were positive for HPV, mainly HPV-16 which was observed in 62.2% of the CC samples. Among CINs, HPV infection was found in 60.2% of the 32 samples with HPV-16 as the dominant genotype in 58.5% of the CINs. IHC analysis revealed a significant increase in the expression levels of both Ki67 and Lamin B1 proteins in CC tissue compared to CIN. On average, 93% of tumor cells were positive for Ki67 in comparison to only 25% of premalignant cells in CIN samples. Similarly, Lamin B1 expression was observed in 89% of tumor cells in malignant tissue on average, compared to 60% in CIN samples. Importantly, Lamin B1 expression was elevated in nonmalignant cervical tissue suggesting that its downregulation is more predominant in the premalignant state. Furthermore, RT-PCR revealed a significant decrease in the expression of TP53, IL1a, CCL2, and MMP9 markers in CC samples compared to CINs. Specifically, 84% of CC samples showed reduced TP53 expression, 90% showed reduced IL1a expression, 74% showed reduced CCL2 expression, and 76% showed reduced MMP9 expression when compared with their premalignant baseline. Infection of HPV was confirmed in 61% of the tumor tissues while only 25% of the CINs were positive for HPV.

CONCLUSION

This work shall provide an opportunity to further examine the role of OIS in the process of HPV-driven CC development.

Integrative Analysis of Radiation-Induced Senescence-Associated Secretory Phenotype Factors in Kidney Cancer Progression

BACKGROUND

Ionizing radiation (IR) is a well-known inducer of cellular senescence and the senescence-associated secretory phenotype (SASP). SASP factors play dual roles in cancer, either promoting or inhibiting its development. This study investigates IR-induced SASP factors specifically secreted by renal cortical epithelial (RCE) cells and their role in promoting renal cell carcinoma (RCC) progression.

METHODS

Proteomic data from the SASP Atlas were analyzed to identify IR-induced factors unique to RCE cells, with subsequent evaluations performed at both the gene and protein levels. Thirty-seven proteins were identified as exclusively upregulated and secreted by senescent RCE cells. Gene expression analysis of these RCE-specific SASP factors was conducted using the Gene Expression database of Normal and Tumor tissues (GENT2) and The Cancer Genome Atlas (TCGA). To assess their prognostic relevance in RCC, the corresponding proteins were further analyzed using the Human Protein Atlas (HPA), emphasizing the relationship between SASP factor expression and RCC progression.

RESULTS

ALDH18A1 and ASPH emerged as key RCE-specific SASP factors with significant upregulation at both the gene and protein levels (Log2 ratio > 1.15, p < 0.05). These proteins are implicated in pro-cancer activities and are strongly associated with poor prognostic outcomes in RCC. Their critical roles in RCC progression underscore their potential as promising therapeutic targets for the prevention and treatment of the disease.

CONCLUSIONS

This study provides novel insights into the role of IR-induced SASP in renal carcinogenesis, marking the first identification of ALDH18A1 and ASPH as specific secreted proteins associated with tumor progression in RCC. This study suggests that ALDH18A1 and ASPH hold promise as early biomarkers for RCC and as therapeutic targets for disease prevention and treatment.

METTL3-regulated m6A modification of lncRNA E230001N04Rik is involved in myofibroblast differentiation in arsenic-induced pulmonary fibrosis through promoting senescence of lung epithelial cells

Arsenic is a toxic agent that causes respiratory damage. Long non-coding RNAs (lncRNAs) are non-coding transcripts that adsorb specific miRNAs and regulate biological processes of human diseases. N6-Methyladenosine (m6A) is an internal modification of RNAs. However, there are few reports about lncRNAs and m6A modifications as co-regulators of pulmonary fibrosis. For 6 months, C57BL/6 mice were given water containing 0, 10, or 20 ppm arsenite. meRIP-seq and lncRNA-seq analyses showed that the m6A levels of the lncRNA E230001N04Rik were higher, and the levels of E230001N04Rik itself were lower in the high-dose arsenite group than in the controls. Murine lung epithelial 12 (MLE12) cells, exposed to 8 μM arsenite for 8 passages, had elevated METTL3 and miR-20b-3p and low E230001N04Rik. Arsenite induced cellular senescence, as demonstrated by secretion of factors related to the senescence-associated secretory phenotype (SASP). Arsenite-treated MLE12 cells co-cultured with primary lung fibroblasts (PLFs) caused myofibroblast differentiation. These data show that METTL3 reduces E230001N04Rik expression via controlling its m6A levels, which regulate miR-20b-3p and mediate the senescence of alveolar epithelial cells (AECs). Thereby, E230001N04Rik is involved in the arsenite-induced myofibroblast differentiation and in pulmonary fibrosis. These observations provide a prospective mechanism for chronic pulmonary disease caused by arsenite.

Variable Expression of Oncogene-Induced Senescence/SASP Surrogates in HPV-Associated Precancerous Cervical Tissue

Oncogene-induced senescence (OIS) is a form of cellular senescence triggered by oncogenic signaling and, potentially, by infection with oncogenic viruses. The role of senescence, along with its associated secretory phenotype, in the development of cervical cancer remains unclear. Additionally, the expression of the senescence-associated secretory phenotype (SASP) has not yet been explored in cervical premalignant lesions infected by the Human Papilloma Virus (HPV). This study aimed to investigate the expression of OIS and SASP markers in HPV-infected cervical precancerous lesions. We used a set of patient-derived precancerous (n = 32) and noncancerous (chronic cervicitis; n = 10) tissue samples to investigate the gene expression of several OIS (LMNB1, CDKN2A, CDKN2B, and CDKN1A), and SASP (IL1A, CCL2, TGFB1, CXCL8, and MMP9) biomarkers using qRT-PCR. OIS status was confirmed in precancerous lesions based on Lamin B1 downregulation by immunohistochemical staining. HPV status for all precancerous lesions was tested. Most of the noncancerous samples showed high Lamin B1 expression, however, precancerous lesions exhibited significant Lamin B1 downregulation (p < 0.001). Fifty-five percent of the precancerous samples were positive for HPV infection, with HPV-16 as the dominant genotype. Lamin B1 downregulation coincided with HPV E6 positive expression. CDKN2A and CDKN2B expression was higher in precancerous lesions compared to noncancerous tissue, while LMNB1 was downregulated. The SASP profile of premalignant lesions included elevated CXCL8 and TGFB1 and reduced IL1A, CCL2, and MMP9. this work shall provide an opportunity to further examine the role of OIS and the SASP in the process of malignant cervical transformation.

Vagus nerve stimulation: Novel concept for the treatment of glioblastoma and solid cancers by cytokine (interleukin-6) reduction, attenuating the SASP, enhancing tumor immunity

Immuno-oncology, specifically immune checkpoint inhibitors (ICIs), has revolutionized cancer care with dramatic, long-term responses and increased survival, including patients with metastatic cancer to the brain. Glioblastomas, and other primary brain tumors, are refractory to ICIs as monotherapy or in combination with standard therapy. The tumor microenvironment (TME) poses multiple biological hurdles: blood-brain barrier, immune suppression, heterogeneity, and tumor infiltration. Genomic analysis of the senescence-associated secretory phenotype (SASP) and preclinical models of glioma suggest that an exciting approach would entail reprogramming of the glioma microenvironment, attenuating the pro-inflammatory, pro-tumorigenic cytokines of the SASP, especially interleukin-6 (IL-6). A testable hypothesis now proposed is to modulate the immune system by harnessing the body's 'inflammatory reflex' to reduce cytokines. Vagus nerve stimulation can activate T cell immunity by the cholinergic, α7nicotinic acetylcholine receptor agonist (α7nAchR), and suppress IL-6 systemically, as well as other pro-inflammatory cytokines of the SASP, interleukin -1β (IL-1β) and tumor necrosis factor-alpha (TNF-α). The hypothesis predicts that electrical activation of the vagus nerve, with cytokine reduction, in combination with ICIs, would convert an immune resistant ("cold") tumor to an immune responsive ("hot") tumor, and halt glioma progression. The hypothesis also envisions cancer as an immune "dysautonomia" whereby a therapeutic intervention, vagus nerve stimulation (VNS), resets the systemic and local cytokine levels. A prospective, randomized, phase II clinical trial, to confirm the hypothesis, is a logical, exigent, next step. Cytokine reduction by VNS could also be useful for other forms of human cancer, e.g., breast, colorectal, head and neck, lung, melanoma, ovarian, pancreatic, and prostate cancer, as the emerging field of "cancer neuroscience" shows a role for neural regulation of multiple tumor types. Because IL-6, and companion pro-inflammatory cytokines, participate in the initiation, progression, spread and recurrence of cancer, minimally invasive VNS could be employed to suppress glioma or cancer progression, while also mitigating depression and/or seizures, thereby enhancing quality of life. The current hypothesis reimagines glioma pathophysiology as a dysautonomia with the therapeutic objective to reset the autonomic nervous system and form an immune responsive state to halt tumor progression and prevent recurrence. VNS, as a novel method to control cancer, can be administered with ICIs, standard therapy, or in clinical trials, combined with emerging immunotherapy: dendritic cell, mRNA, or chimeric antigen receptor (CAR) T cell vaccines.

Advancements in Research on Mesenchymal Stem-Cell-Derived Exosomal miRNAs: A Pivotal Insight into Aging and Age-Related Diseases

Mesenchymal stem cells (MSCs) are capable of differentiating into various cell types and play a crucial role in repairing aging tissues and diseased organs. Aging manifests as a gradual loss of cellular, tissue, and organ function, leading to the progression of pathologies. Exosomes (Exos) are extracellular vesicles secreted by cells, which maintain cellular homeostasis, clear cellular debris, and facilitate communication between cells and organs. This review provides a comprehensive summary of the mechanisms for the synthesis and sorting of MSC-Exo miRNAs and summarizes the current research status of MSCs-Exos in mitigating aging and age-related diseases. It delves into the underlying molecular mechanisms, which encompass antioxidative stress, anti-inflammatory response, and the promotion of angiogenesis. Additionally, this review also discusses potential challenges in and future strategies for advancing MSC-Exo miRNA-based therapies in the treatment of aging and age-related diseases.

Novel Arf1 Inhibitors Drive Cancer Stem Cell Aging and Potentiate Anti-Tumor Immunity

The small G protein Arf1 has been identified as playing a selective role in supporting cancer stem cells (CSCs), making it an attractive target for cancer therapy. However, the current Arf1 inhibitors have limited translational potential due to their high toxicity and low specificity. In this study, two new potent small-molecule inhibitors of Arf1, identified as DU101 and DU102, for cancer therapy are introduced. Preclinical tumor models demonstrate that these inhibitors triggered a cascade of aging in CSCs and enhance anti-tumor immunity in mouse cancer and PDX models. Through single-cell sequencing, the remodeling of the tumor immune microenvironment induced by these new Arf1 inhibitors is analyzed and an increase in tumor-associated CD8+ CD4+ double-positive T (DPT) cells is identified. These DPT cells exhibit superior features of active CD8 single-positive T cells and a higher percentage of TCF1+PD-1+, characteristic of stem-like T cells. The frequency of tumor-infiltrating stem-like DPT cells correlates with better disease-free survival (DFS) in cancer patients, indicating that these inhibitors may offer a novel cancer immunotherapy strategy by converting the cold tumor immune microenvironment into a hot one, thus expanding the potential for immunotherapy in cancer patients.

Senescence Biomarkers CKAP4 and PTX3 Stratify Severe Kidney Disease Patients

INTRODUCTION

Cellular senescence is the irreversible growth arrest subsequent to oncogenic mutations, DNA damage, or metabolic insult. Senescence is associated with ageing and chronic age associated diseases such as cardiovascular disease and diabetes. The involvement of cellular senescence in acute kidney injury (AKI) and chronic kidney disease (CKD) is not fully understood. However, recent studies suggest that such patients have a higher-than-normal level of cellular senescence and accelerated ageing.

METHODS

This study aimed to discover key biomarkers of senescence in AKI and CKD patients compared to other chronic ageing diseases in controls using OLINK proteomics.

RESULTS

We show that senescence proteins CKAP4 (p-value < 0.0001) and PTX3 (p-value < 0.0001) are upregulated in AKI and CKD patients compared with controls with chronic diseases, suggesting the proteins may play a role in overall kidney disease development.

CONCLUSIONS

CKAP4 was found to be differentially expressed in both AKI and CKD when compared to UHCs; hence, this biomarker could be a prognostic senescence biomarker of both AKI and CKD.

Inflammation-Associated Stem Cells in Gastrointestinal Cancers: Their Utility as Prognostic Biomarkers and Therapeutic Targets

Stem cells are critical for the development and homeostasis of the gastrointestinal (GI) tract. Inflammatory molecules are known to regulate the activity of stem cells. A comprehensive review specifically describing the role of inflammatory molecules in the regulation of stem cells within the GI tract and in GI cancers (GICs) is not available. This review focuses on understanding the role of inflammatory molecules and stem cells in maintaining homeostasis of the GI tract. We further discuss how inflammatory conditions contribute to the transformation of stem cells into tumor-initiating cells. We also describe the molecular mechanisms of inflammation and stem cell-driven progression and metastasis of GICs. Furthermore, we report on studies describing the prognostic value of cancer stem cells and the clinical trials evaluating their therapeutic utility. This review provides a detailed overview on the role of inflammatory molecules and stem cells in maintaining GI tract homeostasis and their implications for GI-related malignancies.

Targeting Cell Senescence and Senolytics: Novel Interventions for Age-Related Endocrine Dysfunction

Multiple changes occur in hormonal regulation with aging and across various endocrine organs. These changes are associated with multiple age-related disorders and diseases. A better understanding of responsible underling biological mechanisms could help in the management of multiple endocrine disorders over and above hormone replacement therapy (HRT). Cellular senescence is involved in multiple biological aging processes and pathologies common in elderly individuals. Cellular senescence, which occurs in many older individuals but also across the lifespan in association with tissue damage, acute and chronic diseases, certain drugs, and genetic syndromes, may contribute to such endocrine disorders as osteoporosis, metabolic syndrome, and type 2 diabetes mellitus. Drugs that selectively induce senescent cell removal, "senolytics,", and drugs that attenuate the tissue-destructive secretory state of certain senescent cells, "senomorphics," appear to delay the onset of or alleviate multiple diseases, including but not limited to endocrine disorders such as diabetes, complications of obesity, age-related osteoporosis, and cancers as well as atherosclerosis, chronic kidney disease, neurodegenerative disorders, and many others. More than 30 clinical trials of senolytic and senomorphic agents have already been completed, are underway, or are planned for a variety of indications. Targeting senescent cells is a novel strategy that is distinct from conventional therapies such as HRT, and thus might address unmet medical needs and can potentially amplify effects of established endocrine drug regimens, perhaps allowing for dose decreases and reducing side effects.

Cellular senescence and metabolic reprogramming: Unraveling the intricate crosstalk in the immunosuppressive tumor microenvironment

The intrinsic oncogenic mechanisms and properties of the tumor microenvironment (TME) have been extensively investigated. Primary features of the TME include metabolic reprogramming, hypoxia, chronic inflammation, and tumor immunosuppression. Previous studies suggest that senescence-associated secretory phenotypes that mediate intercellular information exchange play a role in the dynamic evolution of the TME. Specifically, hypoxic adaptation, metabolic dysregulation, and phenotypic shifts in immune cells regulated by cellular senescence synergistically contribute to the development of an immunosuppressive microenvironment and chronic inflammation, thereby promoting the progression of tumor events. This review provides a comprehensive summary of the processes by which cellular senescence regulates the dynamic evolution of the tumor-adapted TME, with focus on the complex mechanisms underlying the relationship between senescence and changes in the biological functions of tumor cells. The available findings suggest that components of the TME collectively contribute to the progression of tumor events. The potential applications and challenges of targeted cellular senescence-based and combination therapies in clinical settings are further discussed within the context of advancing cellular senescence-related research.

Alterations of receptors and insulin-like growth factor binding proteins in senescent cells

The knowledge about cellular senescence expands dynamically, providing more and more conclusive evidence of its triggers, mechanisms, and consequences. Senescence-associated secretory phenotype (SASP), one of the most important functional traits of senescent cells, is responsible for a large extent of their context-dependent activity. Both SASP's components and signaling pathways are well-defined. A literature review shows, however, that a relatively underinvestigated aspect of senescent cell autocrine and paracrine activity is the change in the production of proteins responsible for the reception and transmission of SASP signals, i.e., receptors and binding proteins. For this reason, we present in this article the current state of knowledge regarding senescence-associated changes in cellular receptors and insulin-like growth factor binding proteins. We also discuss the role of these alterations in senescence induction and maintenance, pro-cancerogenic effects of senescent cells, and aging-related structural and functional malfunctions.

Leveraging Senescent Cancer Cell Membrane to Potentiate Cancer Immunotherapy Through Biomimetic Nanovaccine

Senescent cancer cells are endowed with high immunogenic potential that has been leveraged to elicit antitumor immunity and potentially complement anticancer therapies. However, the efficacy of live senescent cancer cell-based vaccination is limited by interference from immunosuppressive senescence-associated secretory phenotype and pro-tumorigenic capacity of senescent cells. Here, a senescent cancer cell-based nanovaccine with strong immunogenicity and favorable potential for immunotherapy is reported. The biomimetic nanovaccine integrating a senescent cancer cell membrane-coated nanoadjuvant outperforms living senescent cancer cells in enhancing dendritic cells (DCs) internalization, improving lymph node targeting, and enhancing immune responses. In contrast to nanovaccines generated from immunogenic cell death-induced tumor cells, senescent nanovaccines facilitate DC maturation, eliciting superior antitumor protection and improving therapeutic outcomes in melanoma-challenged mice with fewer side effects when combined with αPD-1. The study suggests a versatile biomanufacturing approach to maximize immunogenic potential and minimize adverse effects of senescent cancer cell-based vaccination and advances the design of biomimetic nanovaccines for cancer immunotherapy.

Cell senescence in liver diseases: pathological mechanism and theranostic opportunity

The liver is not oblivious to the passage of time, as ageing is a major risk factor for the development of acute and chronic liver diseases. Ageing produces alterations in all hepatic cells, affecting their phenotype and function and worsening the prognosis of liver disease. The ageing process also implies the accumulation of a cellular state characterized by a persistent proliferation arrest and a specific secretory phenotype named cellular senescence. Indeed, senescent cells have key roles in many physiological processes; however, their accumulation owing to ageing or pathological conditions contributes to the damage occurring in chronic diseases. The aim of this Review is to provide an updated description of the pathophysiological events in which hepatic senescent cells are involved and their role in liver disease progression. Finally, we discuss novel geroscience therapies that could be applied to prevent or improve liver diseases and age-mediated hepatic deregulations.

Engineering principles for rationally design therapeutic strategies against hepatocellular carcinoma

The search for new therapeutic strategies against cancer has favored the emergence of rationally designed treatments. These treatments have focused on attacking cell plasticity mechanisms to block the transformation of epithelial cells into cancerous cells. The aim of these approaches was to control particularly lethal cancers such as hepatocellular carcinoma. However, they have not been able to control the progression of cancer for unknown reasons. Facing this scenario, emerging areas such as systems biology propose using engineering principles to design and optimize cancer treatments. Beyond the possibilities that this approach might offer, it is necessary to know whether its implementation at a clinical level is viable or not. Therefore, in this paper, we will review the engineering principles that could be applied to rationally design strategies against hepatocellular carcinoma, and discuss whether the necessary elements exist to implement them. In particular, we will emphasize whether these engineering principles could be applied to fight hepatocellular carcinoma.

Cellular Aging and Senescence in Cancer: A Holistic Review of Cellular Fate Determinants

This comprehensive review navigates the complex relationship between cellular aging, senescence, and cancer, unraveling the determinants of cellular fate. Beginning with an overview of cellular aging's significance in cancer, the review explores processes, changes, and molecular pathways influencing senescence. The review explores senescence as a dual mechanism in cancer, acting as a suppressor and contributor, focusing on its impact on therapy response. This review highlights opportunities for cancer therapies that target cellular senescence. The review further examines the senescence-associated secretory phenotype and strategies to modulate cellular aging to influence tumor behavior. Additionally, the review highlights the mechanisms of senescence escape in aging and cancer cells, emphasizing their impact on cancer prognosis and resistance to therapy. The article addresses current advances, unexplored aspects, and future perspectives in understanding cellular aging and senescence in cancer.

Endothelial CLEC-1b plays a protective role against cancer hematogenous metastasis

Metastasis, which is the spread of cancer cells into distant organs, is a critical determinant of prognosis in patients with cancer, and blood vessels are the major route for cancer cells to spread systemically. Extravasation is a critical process for the hematogenous metastasis; however, its underlying molecular mechanisms remain poorly understood. Here, we identified that senescent ECs highly express C-type lectin domain family 1 member B (CLEC-1b), and that endothelial CLEC-1b inhibits the hematogenous metastasis of a certain type of cancer. CLEC-1b expression was enhanced in ECs isolated from aged mice, senescent cultured human ECs, and ECs of aged human. CLEC-1b overexpression in ECs prevented the disruption of endothelial integrity, and inhibited the transendothelial migration of cancer cells expressing podoplanin (PDPN), a ligand for CLEC-1b. Notably, target activation of CLEC-1b in ECs decreased the hematogenous metastasis in the lungs by cancer cells expressing PDPN in mice. Our data reveal the protective role of endothelial CLEC-1b against cancer hematogenous metastasis. Considering the high CLEC-1b expression in senescent ECs, EC senescence may play a beneficial role with respect to the cancer hematogenous metastasis.

Emerging Roles of Vitamin B12 in Aging and Inflammation

Vitamin B12 (cobalamin) is an essential nutrient for humans and animals. Metabolically active forms of B12-methylcobalamin and 5-deoxyadenosylcobalamin are cofactors for the enzymes methionine synthase and mitochondrial methylmalonyl-CoA mutase. Malfunction of these enzymes due to a scarcity of vitamin B12 leads to disturbance of one-carbon metabolism and impaired mitochondrial function. A significant fraction of the population (up to 20%) is deficient in vitamin B12, with a higher rate of deficiency among elderly people. B12 deficiency is associated with numerous hallmarks of aging at the cellular and organismal levels. Cellular senescence is characterized by high levels of DNA damage by metabolic abnormalities, increased mitochondrial dysfunction, and disturbance of epigenetic regulation. B12 deficiency could be responsible for or play a crucial part in these disorders. In this review, we focus on a comprehensive analysis of molecular mechanisms through which vitamin B12 influences aging. We review new data about how deficiency in vitamin B12 may accelerate cellular aging. Despite indications that vitamin B12 has an important role in health and healthy aging, knowledge of the influence of vitamin B12 on aging is still limited and requires further research.

Neutrophil-activating secretome characterizes palbociclib-induced senescence of breast cancer cells

Senescent cells have a profound impact on the surrounding microenvironment through the secretion of numerous bioactive molecules and inflammatory factors. The induction of therapy-induced senescence by anticancer drugs is known, but how senescent tumor cells influence the tumor immune landscape, particularly neutrophil activity, is still unclear. In this study, we investigate the induction of cellular senescence in breast cancer cells and the subsequent immunomodulatory effects on neutrophils using the CDK4/6 inhibitor palbociclib, which is approved for the treatment of breast cancer and is under intense investigation for additional malignancies. Our research demonstrates that palbociclib induces a reversible form of senescence endowed with an inflammatory secretome capable of recruiting and activating neutrophils, in part through the action of interleukin-8 and acute-phase serum amyloid A1. The activation of neutrophils is accompanied by the release of neutrophil extracellular trap and the phagocytic removal of senescent tumor cells. These findings may be relevant for the success of cancer therapy as neutrophils, and neutrophil-driven inflammation can differently affect tumor progression. Our results reveal that neutrophils, as already demonstrated for macrophages and natural killer cells, can be recruited and engaged by senescent tumor cells to participate in their clearance. Understanding the interplay between senescent cells and neutrophils may lead to innovative strategies to cope with chronic or tumor-associated inflammation.

Cellular senescence in cancer: molecular mechanisms and therapeutic targets

Aging exhibits several hallmarks in common with cancer, such as cellular senescence, dysbiosis, inflammation, genomic instability, and epigenetic changes. In recent decades, research into the role of cellular senescence on tumor progression has received widespread attention. While how senescence limits the course of cancer is well established, senescence has also been found to promote certain malignant phenotypes. The tumor-promoting effect of senescence is mainly elicited by a senescence-associated secretory phenotype, which facilitates the interaction of senescent tumor cells with their surroundings. Targeting senescent cells therefore offers a promising technique for cancer therapy. Drugs that pharmacologically restore the normal function of senescent cells or eliminate them would assist in reestablishing homeostasis of cell signaling. Here, we describe cell senescence, its occurrence, phenotype, and impact on tumor biology. A "one-two-punch" therapeutic strategy in which cancer cell senescence is first induced, followed by the use of senotherapeutics for eliminating the senescent cells is introduced. The advances in the application of senotherapeutics for targeting senescent cells to assist cancer treatment are outlined, with an emphasis on drug categories, and the strategies for their screening, design, and efficient targeting. This work will foster a thorough comprehension and encourage additional research within this field.

A new perspective on prostate cancer treatment: the interplay between cellular senescence and treatment resistance

The emergence of resistance to prostate cancer (PCa) treatment, particularly to androgen deprivation therapy (ADT), has posed a significant challenge in the field of PCa management. Among the therapeutic options for PCa, radiotherapy, chemotherapy, and hormone therapy are commonly used modalities. However, these therapeutic approaches, while inducing apoptosis in tumor cells, may also trigger stress-induced premature senescence (SIPS). Cellular senescence, an entropy-driven transition from an ordered to a disordered state, ultimately leading to cell growth arrest, exhibits a dual role in PCa treatment. On one hand, senescent tumor cells may withdraw from the cell cycle, thereby reducing tumor growth rate and exerting a positive effect on treatment. On the other hand, senescent tumor cells may secrete a plethora of cytokines, growth factors and proteases that can affect neighboring tumor cells, thereby exerting a negative impact on treatment. This review explores how radiotherapy, chemotherapy, and hormone therapy trigger SIPS and the nuanced impact of senescent tumor cells on PCa treatment. Additionally, we aim to identify novel therapeutic strategies to overcome resistance in PCa treatment, thereby enhancing patient outcomes.

Anti-aging Factor GRSF1 Attenuates Cerebral Ischemia-Reperfusion Injury in Mice by Inhibiting GPX4-Mediated Ferroptosis

Abnormal accumulation of senescent cells in tissues has been shown to facilitate the onset and progression of various diseases. As an important protein involving in the regulation of cellular senescence process, researches suggested GRSF1 as a potential senolytic target to improve multiple physiological and pathological processes. However, the underlying mechanism of cellular senescence on cerebral ischemia-reperfusion injury (CIRI) has not been revealed. Here, we investigated the effect of GRSF1 on CIRI and delved into its specific mechanisms. In the present study, we established a mouse model of cerebral ischemia-reperfusion (CIR) and observed low expression of anti-aging factor GRSF1, along with greatly increased levels of senescence-related markers p16 and p21 and senescence-associated secretory phenotype TNF-α. Furthermore, we found that the expression of GPX4 was elevated parallel to GRSF1 in CIR mice with overexpression of GRSF1, oxidative stress, and iron metabolism-related proteins were inhibited. Functionally, overexpressing GRSF1 significantly ameliorated infarct volume and neurological function scores and suppressed apoptosis in CIR mice, while administration of GPX4 inhibitors reversed these beneficial phenotypes. Taken together, our results indicate cellular senescence as an important pathological mechanism to exacerbate cerebral injury during CIRI, while GRSF1 could inhibit oxidative stress-mediated ferroptosis through upregulating GPX4 to attenuate reperfusion injury, which makes senolytic treatment, especially GRSF1, a promising therapeutic target for CIRI.

CIP/KIP and INK4 families as hostages of oncogenic signaling

CIP/KIP and INK4 families of Cyclin-dependent kinase inhibitors (CKIs) are well-established cell cycle regulatory proteins whose canonical function is binding to Cyclin-CDK complexes and altering their function. Initial experiments showed that these proteins negatively regulate cell cycle progression and thus are tumor suppressors in the context of molecular oncology. However, expanded research into the functions of these proteins showed that most of them have non-canonical functions, both cell cycle-dependent and independent, and can even act as tumor enhancers depending on their posttranslational modifications, subcellular localization, and cell state context. This review aims to provide an overview of canonical as well as non-canonical functions of CIP/KIP and INK4 families of CKIs, discuss the potential avenues to promote their tumor suppressor functions instead of tumor enhancing ones, and how they could be utilized to design improved treatment regimens for cancer patients.

Senescent fibroblast facilitates re-epithelization and collagen deposition in radiation-induced skin injury through IL-33-mediated macrophage polarization

BACKGROUND

The need for radiotherapy among the elderly rises with increasing life expectancy and a corresponding increase of elderly cancer patients. Radiation-induced skin injury is one of the most frequent adverse effects in radiotherapy patients, severely limiting their life quality. Re-epithelialization and collagen deposition have essential roles in the recovery of skin injuries induced by high doses of ionizing radiation. At the same time, radiation-induced senescent cells accumulate in irradiated tissues. However, the effects and mechanisms of senescent cells on re-epithelialization and collagen deposition in radiation-induced skin injury have not been fully elucidated.

RESULTS

Here, we identified a role for a population of senescent cells expressing p16 in promoting re-epithelialization and collagen deposition in radiation-induced skin injury. Targeted ablation of p16+ senescent cells or treatment with Senolytics resulted in the disruption of collagen structure and the retardation of epidermal coverage. By analyzing a publicly available single-cell sequencing dataset, we identified fibroblasts as a major contributor to the promotion of re-epithelialization and collagen deposition in senescent cells. Notably, our analysis of publicly available transcriptome sequencing data highlighted IL-33 as a key senescence-associated secretory phenotype produced by senescent fibroblasts. Neutralizing IL-33 significantly impedes the healing process. Finally, we found that the effect of IL-33 was partly due to the modulation of macrophage polarization.

CONCLUSIONS

In conclusion, our data suggested that senescent fibroblasts accumulated in radiation-induced skin injury sites participated in wound healing mainly by secreting IL-33. This secretion regulated the local immune microenvironment and macrophage polarization, thus emphasizing the importance of precise regulation of senescent cells in a phased manner.

Differential DNA damage response and cell fate in human lung cells after exposure to genotoxic compounds

DNA damage can impair normal cellular functions and result in various pathophysiological processes including cardiovascular diseases and cancer. We compared the genotoxic potential of diverse DNA damaging agents, and focused on their effects on the DNA damage response (DDR) and cell fate in human lung cells BEAS-2B. Polycyclic aromatic hydrocarbons [PAHs; benzo[a]pyrene (B[a]P), 1-nitropyrene (1-NP)] induced DNA strand breaks and oxidative damage to DNA; anticancer drugs doxorubicin (DOX) and 5-bromo-2'-deoxyuridine (BrdU) were less effective. DOX triggered the most robust p53 signaling indicating activation of DDR, followed by cell cycle arrest in the G2/M phase, induction of apoptosis and senescence, possibly due to the severe and irreparable DNA lesions. BrdU not only activated p53, but also increased the percentage of G1-phased cells and caused a massive accumulation of senescent cells. In contrast, regardless the activation of p53, both PAHs did not substantially affect the cell cycle distribution or senescence. Finally, a small fraction of cells accumulated only in the G2/M phase and exhibited increased cell death after the prolonged incubation with B[a]P. Overall, we characterized differential responses to diverse DNA damaging agents resulting in specific cell fate and highlighted the key role of DNA lesion type and the p53 signaling persistence.

Analysis of the Genetic Characteristics and Metastatic Pathways of G1 and G2 Colorectal Neuroendocrine Neoplasms

Objective

G1 and G2 colorectal neuroendocrine neoplasms (NENs) are a group of rare and indolent diseases. We aimed to delineate their genetic characteristics and explore their metastatic mechanisms.

Methods

We used next-generation sequencing technology for targeted sequencing for 54 patients with G1 and G2 colorectal NENs. We delineated their genetic features and compared the genetic characteristics between metastatic NENs and nonmetastatic NENs. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was utilized to explore their abnormal pathways and study their potential metastatic mechanisms.

Results

We collected 23 metastatic NENs and 31 nonmetastatic NENs. In the whole cohort, the common mutated genes were NCOR2, BRD4, MDC1, ARID1A, AXIN2, etc. The common copy number variations (CNVs) included amplification of HIST1H3D, amplification of HIST1H3E, and loss of PTEN. The KEGG enrichment analysis revealed that PI3K-Akt, MAPK, and Rap1 were the major abnormal pathways. There were significantly different genetic features between metastatic NENs and nonmetastatic NENs. The metastatic NENs shared only 47 (22.5%) mutated genes and 6 (13.3%) CNVs with nonmetastatic NENs. NCOR2, BRD4, CDKN1B, CYP3A5, and EIF1AX were the commonly mutated genes in metastatic NENs, while NCOR2, MDC1, AXIN2, PIK3C2G, and PTPRT were the commonly mutated genes in nonmetastatic NENs. Metastatic NENs presented a significantly higher proportion of abnormal pathways of cell senescence (56.5% vs 25.8%, P = .022) and lysine degradation (43.5% vs 16.1%, P = .027) than nonmetastatic NENs.

Conclusion

G1 and G2 colorectal NENs are a group of heterogeneous diseases that might obtain an increased invasive ability through aberrant cell senescence and lysine degradation pathways.

Eternal Youth: A Comprehensive Exploration of Gene, Cellular, and Pharmacological Anti-Aging Strategies

The improvement of human living conditions has led to an increase in average life expectancy, creating a new social and medical problem-aging, which diminishes the overall quality of human life. The aging process of the body begins with the activation of effector signaling pathways of aging in cells, resulting in the loss of their normal functions and deleterious effects on the microenvironment. This, in turn, leads to chronic inflammation and similar transformations in neighboring cells. The cumulative retention of these senescent cells over a prolonged period results in the deterioration of tissues and organs, ultimately leading to a reduced quality of life and an elevated risk of mortality. Among the most promising methods for addressing aging and age-related illnesses are pharmacological, genetic, and cellular therapies. Elevating the activity of aging-suppressing genes, employing specific groups of native and genetically modified cells, and utilizing senolytic medications may offer the potential to delay aging and age-related ailments over the long term. This review explores strategies and advancements in the field of anti-aging therapies currently under investigation, with a particular emphasis on gene therapy involving adeno-associated vectors and cell-based therapeutic approaches.

Prognostic significance of senescence-related tumor microenvironment genes in head and neck squamous cell carcinoma

The impact of the senescence related microenvironment on cancer prognosis and therapeutic response remains poorly understood. In this study, we investigated the prognostic significance of senescence related tumor microenvironment genes (PSTGs) and their potential implications for immunotherapy response. Using the Cancer Genome Atlas- head and neck squamous cell carcinoma (HNSC) data, we identified two subtypes based on the expression of PSTGs, acquired from tumor-associated senescence genes, tumor microenvironment (TME)-related genes, and immune-related genes, using consensus clustering. Using the LASSO, we constructed a risk model consisting of senescence related TME core genes (STCGs). The two subtypes exhibited significant differences in prognosis, genetic alterations, methylation patterns, and enriched pathways, and immune infiltration. Our risk model stratified patients into high-risk and low-risk groups and validated in independent cohorts. The high-risk group showed poorer prognosis and immune inactivation, suggesting reduced responsiveness to immunotherapy. Additionally, we observed a significant enrichment of STCGs in stromal cells using single-cell RNA transcriptome data. Our findings highlight the importance of the senescence related TME in HNSC prognosis and response to immunotherapy. This study contributes to a deeper understanding of the complex interplay between senescence and the TME, with potential implications for precision medicine and personalized treatment approaches in HNSC.

Opportunities in Cancer Therapies: Deciphering the Role of Cancer Stem Cells in Tumour Repopulation

Tumour repopulation during treatment is a well acknowledged yet still challenging aspect of cancer management. The latest research results show clear evidence towards the existence of cancer stem cells (CSCs) that are responsible for tumour repopulation, dissemination, and distant metastases in most solid cancers. Cancer stem cell quiescence and the loss of asymmetrical division are two powerful mechanisms behind repopulation. Another important aspect in the context of cancer stem cells is cell plasticity, which was shown to be triggered during fractionated radiotherapy, leading to cell dedifferentiation and thus reactivation of stem-like properties. Repopulation during treatment is not limited to radiotherapy, as there is clinical proof for repopulation mechanisms to be activated through other conventional treatment techniques, such as chemotherapy. The dynamic nature of stem-like cancer cells often elicits resistance to treatment by escaping drug-induced cell death. The aims of this scoping review are (1) to describe the main mechanisms used by cancer stem cells to initiate tumour repopulation during therapy; (2) to present clinical evidence for tumour repopulation during radio- and chemotherapy; (3) to illustrate current trends in the identification of CSCs using specific imaging techniques; and (4) to highlight novel technologies that show potential in the eradication of CSCs.

A new face of old cells: An overview about the role of senescence and telomeres in inflammatory bowel diseases

Cellular senescence is a pivotal factor contributing to aging and the pathophysiology of age-related diseases. Despite the presence of inflammation and abnormal immune system function in both inflammatory bowel diseases (IBD) and senescence, the relationship between the two remains largely unexplored. Therefore, our study aimed to investigate the intricate connection between cellular senescence, telomeres, and IBD. The review highlights the presence of senescence markers, particularly p16 and p21, in IBD patients, suggesting their potential association with disease progression and mucosal inflammation. We emphasize the critical role of macrophages in eliminating senescent cells and how disturbance in effective clearance may contribute to persistent senescence and inflammation in IBD. Additionally, we shed light on the involvement of telomeres in IBD, as their dysfunction impairs enterocyte function and disrupts colonic barrier integrity, potentially exacerbating the pathogenesis of the disease. Targeting senescence and telomere dysfunctions holds promise for the development of innovative therapeutic approaches to mitigate intestinal inflammation and alleviate symptoms in IBD patients. By unraveling the precise role of senescence in IBD, we can pave the way for the discovery of novel therapeutic interventions that effectively address the underlying mechanisms of intestinal inflammation, offering hope for improved management and treatment of IBD patients.

Immune Diseases Associated with Aging: Molecular Mechanisms and Treatment Strategies

Aging is associated with a decline in immune function, thereby causing an increased susceptibility to various diseases. Herein, we review immune diseases associated with aging, focusing on tumors, atherosclerosis, and immunodeficiency disorders. The molecular mechanisms underlying these conditions are discussed, highlighting telomere shortening, tissue inflammation, and altered signaling pathways, e.g., the mammalian target of the rapamycin (mTOR) pathway, as key contributors to immune dysfunction. The role of the senescence-associated secretory phenotype in driving chronic tissue inflammation and disruption has been examined. Our review underscores the significance of targeting tissue inflammation and immunomodulation for treating immune disorders. In addition, anti-inflammatory medications, including corticosteroids and nonsteroidal anti-inflammatory drugs, and novel approaches, e.g., probiotics and polyphenols, are discussed. Immunotherapy, particularly immune checkpoint inhibitor therapy and adoptive T-cell therapy, has been explored for its potential to enhance immune responses in older populations. A comprehensive analysis of immune disorders associated with aging and underlying molecular mechanisms provides insights into potential treatment strategies to alleviate the burden of these conditions in the aging population. The interplay among immune dysfunction, chronic tissue inflammation, and innovative therapeutic approaches highlights the importance of elucidating these complex processes to develop effective interventions to improve the quality of life in older adults.

A multi-omics integrative approach unravels novel genes and pathways associated with senescence escape after targeted therapy in NRAS mutant melanoma

Therapy Induced Senescence (TIS) leads to sustained growth arrest of cancer cells. The associated cytostasis has been shown to be reversible and cells escaping senescence further enhance the aggressiveness of cancers. Chemicals specifically targeting senescent cells, so-called senolytics, constitute a promising avenue for improved cancer treatment in combination with targeted therapies. Understanding how cancer cells evade senescence is needed to optimise the clinical benefits of this therapeutic approach. Here we characterised the response of three different NRAS mutant melanoma cell lines to a combination of CDK4/6 and MEK inhibitors over 33 days. Transcriptomic data show that all cell lines trigger a senescence programme coupled with strong induction of interferons. Kinome profiling revealed the activation of Receptor Tyrosine Kinases (RTKs) and enriched downstream signaling of neurotrophin, ErbB and insulin pathways. Characterisation of the miRNA interactome associates miR-211-5p with resistant phenotypes. Finally, iCell-based integration of bulk and single-cell RNA-seq data identifies biological processes perturbed during senescence and predicts 90 new genes involved in its escape. Overall, our data associate insulin signaling with persistence of a senescent phenotype and suggest a new role for interferon gamma in senescence escape through the induction of EMT and the activation of ERK5 signaling.

Research progress of AMP-activated protein kinase and cardiac aging

The process of aging is marked by a gradual deterioration in the physiological functions and functional reserves of various tissues and organs, leading to an increased susceptibility to diseases and even death. Aging manifests in a tissue- and organ-specific manner, and is characterized by varying rates and direct and indirect interactions among different tissues and organs. Cardiovascular disease (CVD) is the leading cause of death globally, with older adults (aged >70 years) accounting for approximately two-thirds of CVD-related deaths. The prevalence of CVD increases exponentially with an individual's age. Aging is a critical independent risk factor for the development of CVD. AMP-activated protein kinase (AMPK) activation exerts cardioprotective effects in the heart and restores cellular metabolic functions by modulating gene expression and regulating protein levels through its interaction with multiple target proteins. Additionally, AMPK enhances mitochondrial function and cellular energy status by facilitating the utilization of energy substrates. This review focuses on the role of AMPK in the process of cardiac aging and maintaining normal metabolic levels and redox homeostasis in the heart, particularly in the presence of oxidative stress and the invasion of inflammatory factors.