Immunosenescence profile and expression of the aging biomarker (p16INK4a) in testicular cancer survivors treated with chemotherapy

Review of evidence linking exposure to environmental stressors and associated alterations in the dynamics of immunosenescence (ISC) with the global increase in multiple sclerosis (MS)

Historical survey confirms that, over the latter part of the 20th century, autoimmune-based diseases, including multiple sclerosis (MS), have shown a worldwide increase in incidence and prevalence. Analytical population studies have established that the exponential rise in MS is not solely due to improvements in diagnosis and healthcare but relates to an increase in autoimmune risk factors. Harmful environmental exposures, including non-communicable social determinants of health, anthropogens and indigenous or transmissible microbes, constitute a group of causal determinants that have been closely linked with the global rise in MS cases. Exposure to environmental stressors has profound effects on the adaptive arm of the immune system and, in particular, the associated intrinsic process of immune ageing or immunosenescence (ISC). Stressor-related disturbances to the dynamics of ISC include immune cell-linked untimely or premature (p) alterations and an accelerated replicative (ar) change. A recognised immune-associated feature of MS is pISC and current evidence supports the presence of an arISC during the disease. Moreover, collated data illustrates the immune-associated alterations that characterise pISC and arISC are inducible by environmental stressors strongly implicated in causing duplicate changes in adaptive immune cells during MS. The close relationship between exposure to environmental risk factors and the induction of pISC and arISC during MS offers a valid mechanism through which pro-immunosenescent stressors may act and contribute to the recorded increase in the global rate and number of new cases of the disease. Confirmation of alterations to the dynamics of ISC during MS provides a rational and valuable therapeutic target for the use of senolytic drugs to either prevent accumulation and enhance ablation of less efficient untimely senescent adaptive immune cells or decelerate the dysregulated process of replicative proliferation. A range of senotherapeutics are available including kinase and transcriptase inhibitors, rapalogs, flavanols and genetically-engineered T cells and the use of selective treatments to control emerging and unspecified aspects of pISC and arISC are discussed.

Aging-related biomarkers in testicular cancer survivors after different oncologic treatments

PURPOSE

Testicular cancer survivors (TCS) exposed to chemotherapy have an increased expression of CDKN2A/p16INK4a and a lymphocyte phenotype associated with immunosenescence. We seek to define whether the immunosenescent phenotype is associated with chemotherapy.

METHODS

Case-control study of TCS, disease-free ≥3 months and stratified by primary treatment modality into orchiectomy only, chemotherapy, or bone marrow transplant (BMT). Each group was compared with age-matched healthy controls (HC). We measured the relative proportions of lymphocyte subpopulations using flow cytometry, levels of C-reactive protein, and relative expression of CDKN2A/p16INK4a quantified by qPCR.

RESULTS

We included 65 patients; 19 were treated with orchiectomy only, 35 received different doses of chemotherapy, and 11 underwent BMT. The chemotherapy and BMT groups had decreased naïve CD4 cells compared to HC. The chemotherapy group showed increased central and effector memory CD4 cells, as well as effector and terminally differentiated CD8 cells, compared to HC. Chemotherapy (chemotherapy 1.84 vs. HC 0.92; p < 0.01) and BMT (BMT 6.96 vs. HC 1.25; p < 0.005) groups had higher expression of CDKN2A/p16INK4a compared to HC. The orchiectomy group showed no significant difference with HC (orchiectomy 1.73 vs. HC 1.01; p = 0.17). CRP levels were higher in all groups when compared with HC; in the orchiectomy group, they were only marginally increased (chemotherapy 0.22 vs. HC 0.06; p < 0.01; BMT 0.26 vs. HC 0.06; p < 0.01; orchiectomy 0.09 vs. HC 0.07; p < 0.01).

CONCLUSIONS

Among TCS, only patients exposed to cytotoxic agents developed an immunosenescent phenotype. This finding supports the attribution of this alteration to the cytotoxic treatment.

Senescence marker p16INK4a expression in patients with multiple sclerosis

OBJECTIVES

Telomere attrition is associated with disability accumulation and brain atrophy in multiple sclerosis (MS). Downstream of telomere attrition is cellular senescence. We sought to determine differences in the cellular senescence marker p16INK4a expression between MS and healthy control participants and the association of p16INK4a expression with MS disability and treatment exposure.

METHODS

Patients meeting diagnostic criteria for MS and healthy controls were recruited for a cross-sectional pilot study. RNA was extracted from peripheral blood mononuclear cells (PBMCs) and p16INK4a expression levels were measured using qRT PCR. Spearman correlation coefficients and regression models were applied to compare expression levels to chronological age, assess case control differences, and determine associations with clinical outcome measures.

RESULTS

Fifty-two participants with MS (67 % female, ages 25-70) and 38 healthy controls (66 % female, ages 23-65) were included. p16INK4a levels were not linearly correlated with chronological age in MS (rhos = -0.01, p = 0.94) or control participants (rhos = 0.02, p = 0.92). Higher median p16INK4a levels were observed in the >50-year age group for MS (0.25, IQR 0.14-0.35) vs. controls (0.12, IQR 0.05-0.15) and in this age group B cell depletion therapy was associated with lower expression levels. p16INK4a expression was not associated with any of the measured MS disability outcomes.

DISCUSSION

Caution is needed with using p16INK4a expression level from PBMCs as an aging biomarker in MS participants, given lack of correlation with chronological age or large associations with clinical outcomes.

Accelerated Aging in Cancer Survivors: Cellular Senescence, Frailty, and Possible Opportunities for Interventions

The population of cancer survivors has markedly increased due to the rapid improvements in cancer treatment. However, cancer survivors experience accelerated aging, which leads to chronic diseases and other age-related conditions, such as frailty. Those conditions may persist years after cancer diagnosis and treatment. Cellular senescence, a hallmark of aging, is one of the mechanisms that contribute to accelerated aging in cancer survivors. Several aging measures, including measures based on clinical markers and biomarkers, have been proposed to estimate the aging process, and some of them have shown associations with mortality and frailty in cancer survivors. Several anti-aging interventions, including lifestyle changes and anti-aging drugs, have been proposed. Future research, particularly in large-scale studies, is needed to determine the efficiency of these aging measures and anti-aging interventions before considering their application in clinics. This review focuses on the mechanisms of cellular senescence and accelerated aging in cancer survivors, assessment of the aging process using clinical markers and biomarkers, and the high prevalence of frailty in that population, as well as possible opportunities for anti-aging interventions. A deeper understanding of aging measures and anti-aging interventions in cancer survivors will contribute to the development of effective strategies to mitigate accelerated aging in cancer survivors and improve their quality of life.

Identification and immuno-infiltration analysis of cuproptosis regulators in human spermatogenic dysfunction

Introduction: Cuproptosis seems to promote the progression of diverse diseases. Hence, we explored the cuproptosis regulators in human spermatogenic dysfunction (SD), analyzed the condition of immune cell infiltration, and constructed a predictive model.

Methods: Two microarray datasets (GSE4797 and GSE45885) related to male infertility (MI) patients with SD were downloaded from the Gene Expression Omnibus (GEO) database. We utilized the GSE4797 dataset to obtain differentially expressed cuproptosis-related genes (deCRGs) between SD and normal controls. The correlation between deCRGs and immune cell infiltration status was analyzed. We also explored the molecular clusters of CRGs and the status of immune cell infiltration. Notably, weighted gene co-expression network analysis (WGCNA) was used to identify the cluster-specific differentially expressed genes (DEGs). Moreso, gene set variation analysis (GSVA) was performed to annotate the enriched genes. Subsequently, we selected an optimal machine-learning model from four models. Finally, nomograms, calibration curves, decision curve analysis (DCA), and the GSE45885 dataset were utilized to verify the predictions’ accuracy.

Results: Among SD and normal controls, we confirmed that there are deCRGs and activated immune responses. Through the GSE4797 dataset, we obtained 11 deCRGs. ATP7A, ATP7B, SLC31A1, FDX1, PDHA1, PDHB, GLS, CDKN2A, DBT, and GCSH were highly expressed in testicular tissues with SD, whereas LIAS was lowly expressed. Additionally, two clusters were identified in SD. Immune-infiltration analysis showed the existing heterogeneity of immunity at these two clusters. Cuproptosis-related molecular Cluster2 was marked by enhanced expressions of ATP7A, SLC31A1, PDHA1, PDHB, CDKN2A, DBT, and higher proportions of resting memory CD4+ T cells. Furthermore, an eXtreme Gradient Boosting (XGB) model based on 5-gene was built, which showed superior performance on the external validation dataset GSE45885 (AUC = 0.812). Therefore, the combined nomogram, calibration curve, and DCA results demonstrated the accuracy of predicting SD.

Conclusion: Our study preliminarily illustrates the relationship between SD and cuproptosis. Moreover, a bright predictive model was developed.

The LncRNA MIAT is identified as a regulator of stemness-associated transcript in glioma

BACKGROUND

Myocardial infarction-associated transcript (MIAT) is a long non-coding RNA (lncRNA) with altered expression in different diseases and malignancies. In this study, the potential expression and function of lncRNA MIAT in intuition and progression of brain cancer was investigated.

METHODS AND RESULTS

At first, TCGA data analysis demonstrated that lncRNA MIAT is significantly upregulated in various malignancies, especially its expression is dramatically elevated in brain tumors. In line with the data, we further evaluated the expression of MIAT in a series of brain tumor tissue, and our results revealed that the expression of MIAT was noticeably overexpressed in glioblastoma (p = < 0.0001). We further found that the expression of MIAT was markedly upregulated in low-grade brain tumors rather than high-grade ones. To further investigate the biological function of MIAT in brain cancer cells, its expression was suppressed by si-RNA-mediated knocking down. Inhibition of MIAT resulted in reduced proliferation of brain tumor cells followed by cell cycle arrest at the G1 phase, and significant induction of apoptosis, and senescence, but limited the migration ability and epithelial-mesenchymal-transition (EMT). Moreover, knocking-down of MIAT reduced the expression of stemness factors, followed by upregulation of their downstream miRNAs (micro RNAs), let-7a-5p, and miR-29b-3p.

CONCLUSIONS

Altogether, our data demonstrated that lncRNA MIAT could control proliferation, migration, and metastasis of brain cancer cells via regulating the Nanog/ Sox2 / let-7a-5p / miR-29b-3p axis. This data could introduce lncRNA MIAT as a novel oncogene in brain cancer pathogenesis.

Premature aging in childhood cancer survivors

Progress in medicine has increased the survival time of children suffering from cancer; >80% of patients survive for at least 5 years from the end of treatment. However, there are late effects of anticancer therapy, which accompany this success. Two-thirds of childhood cancer survivors (CCSs) have at least one late effect (any side effects or complications of anticancer treatment that appear months to years after the completion of treatment), e.g. endocrinopathies, cardiovascular diseases or subsequent cancers, and half of these late effects are serious or life threatening. These late consequences of childhood cancer treatment pose a serious health, social and economic problem. A common mechanism for developing a number of late effects is the onset of premature biological aging, which is associated with the early onset of chronic diseases and death. Cellular senescence in cancer survivors is caused by therapy that can induce chromosomal aberrations, mutations, telomere shortening, epigenetic alterations and mitochondrial dysfunctions. The mechanisms of accelerated aging in cancer survivors have not yet been fully clarified. The measurement of biological age in survivors can help improve the understanding of aging mechanisms and identify risk factors for premature aging. However, to the best of our knowledge, no single marker for the evaluation of biological or functional age is known, so it is therefore necessary to measure the consequences of anticancer treatment using complex assessments. The present review presents an overview of premature aging in CCSs and of the mechanisms involved in its development, focusing on the association of senescence and late effects.

Upregulation of p16INK4A in Peripheral White Blood Cells as a Novel Screening Marker for Colorectal Carcinoma

OBJECTIVE

Screening of colorectal cancer (CRC) is important for the early detection. CRC is relating to aging and immuno-senescence. One such senescent marker is p16INK4A expression in immune cells. The objective of the study is to investigate the protein expression of p16INK4A in peripheral white blood cells as a screening marker for colorectal cancer.

METHODS

A case-control studies were conducted. Cases were patients with colorectal cancer and controls were matched with cases based on age and sex. Peripheral blood was collected from patients and controls and the protein p16INK4A was measured with immunofluorescent techniques. The p16INK4A levels from cases and controls were evaluated using ROC analysis to be used as a screening marker in CRC patients. Mean fluorescent intensity of p16INK4A of cases and controls were analyzed in CD45+, CD3+ or CD14+ cells. The p16INK4A levels of cases were also correlated with clinical data.

RESULT

Statistically significant increased expression of p16INK4A levels were found in cases compared to controls. p16INK4A in peripheral immune cells had 78% sensitivity and 71% specificity which can possibly be used as a diagnosis tool for colorectal cancer. P16INK4A-positive cell percentage and mean florescent intensity were significantly higher in CD45+ cells, CD3 positive cells and CD14 positive cells. No significant correlation was observed with the clinical data and p16INK4A level of CRC patients.

CONCLUSION

The significant increase of p16 INK4A expression level in peripheral immune cells represents potential for use as a CRC screening marker.

The Achilles' heel of cancer survivors: fundamentals of accelerated cellular senescence

Recent improvements in cancer treatment have increased the lifespan of pediatric and adult cancer survivors. However, cancer treatments accelerate aging in survivors, which manifests clinically as the premature onset of chronic diseases, such as endocrinopathies, osteoporosis, cardiac dysfunction, subsequent cancers, and geriatric syndromes of frailty, among others. Therefore, cancer treatment-induced early aging accounts for significant morbidity, mortality, and health expenditures among cancer survivors. One major mechanism driving this accelerated aging is cellular senescence; cancer treatments induce cellular senescence in tumor cells and in normal, nontumor tissue, thereby helping mediate the onset of several chronic diseases. Studies on clinical monitoring and therapeutic targeting of cellular senescence have made considerable progress in recent years. Large-scale clinical trials are currently evaluating senotherapeutic drugs, which inhibit or eliminate senescent cells to ameliorate cancer treatment-related aging. In this article, we survey the recent literature on phenotypes and mechanisms of aging in cancer survivors and provide an up-to-date review of the major preclinical and translational evidence on cellular senescence as a mechanism of accelerated aging in cancer survivors, as well as insight into the potential of senotherapeutic drugs. However, only with time will the clinical effect of senotherapies on cancer survivors be visible.

Assessment of cell cycle regulators in human peripheral blood cells as markers of cellular senescence

Cellular senescence has gained increasing interest during recent years, particularly due to causal involvement in the aging process corroborated by multiple experimental findings. Indeed, cellular senescence considered to be one of the hallmarks of aging, is defined as a stable growth arrest predominantly mediated by cell cycle regulators p53, p21 and p16. Senescent cells have frequently been studied in the peripheral blood of humans due to its accessibility. This review summarizes ex vivo studies describing cell cycle regulators as markers of senescence in human peripheral blood cells, along with detection methodologies and associative studies examining demographic and clinical characteristics. The utility of techniques such as the quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), microarray, RNA sequencing and nCounter technologies for detection at the transcriptional level, along with Western blotting, enzyme-linked immunosorbent assay and flow cytometry at the translational level, will be brought up at salient points throughout this review. Notably, housekeeping genes or proteins serving as controls such as GAPDH and β-Actin, were found not to be stably expressed in some contexts. As such, optimization and validation of such genes during experimental design were recommended. In addition, the expression of cell cycle regulators was found to vary not only between different types of blood cells such as T cells and B cells but also between stages of cellular differentiation such as naïve T cells and highly differentiated T cells. On the other hand, the associations of the presence of cell cycle regulators with demographics (age, gender, ethnicity, and socioeconomic status), clinical characteristics (body mass index, specific diseases, disease-related parameters) and lifestyle vary in groups of participants. One envisions that increased understanding and insights into the assessment of cell cycle regulators as markers of senescence in human peripheral blood cells will help inform prognostication and clinical intervention in elderly individuals.

Cellular senescence in the cholangiopathies: a driver of immunopathology and a novel therapeutic target

The cholangiopathies are a group of liver diseases that affect cholangiocytes, the epithelial cells that line the bile ducts. Biliary atresia (BA), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) are three cholangiopathies with significant immune-mediated pathogenesis where chronic inflammation and fibrosis lead to obliteration of bile ducts and eventual liver cirrhosis. Cellular senescence is a state of cell cycle arrest in which cells become resistant to apoptosis and profusely secrete a bioactive secretome. Recent evidence indicates that cholangiocyte senescence contributes to the pathogenesis of BA, PBC, and PSC. This review explores the role of cholangiocyte senescence in BA, PBC, and PSC, ascertains how cholangiocyte senescence may promote a senescence-associated immunopathology in these cholangiopathies, and provides the rationale for therapeutically targeting senescence as a treatment option for BA, PBC, and PSC.

Cancer Treatment-Induced Accelerated Aging in Cancer Survivors: Biology and Assessment

Rapid improvements in cancer survival led to the realization that many modalities used to treat or control cancer may cause accelerated aging in cancer survivors. Clinically, "accelerated aging" phenotypes in cancer survivors include secondary cancers, frailty, chronic organ dysfunction, and cognitive impairment, all of which can impact long-term health and quality of life in cancer survivors. The treatment-induced accelerated aging in cancer survivors could be explained by telomere attrition, cellular senescence, stem cell exhaustion, DNA damage, and epigenetic alterations. Several aging clocks and biomarkers of aging have been proposed to be potentially useful in estimating biological age, which can provide specific information about how old an individual is biologically independent of chronological age. Measuring biological age in cancer survivors may be important for two reasons. First, it can better predict the risk of cancer treatment-related comorbidities than chronological age. Second, biological age may provide additional value in evaluating the effects of treatments and personalizing cancer therapies to maximize efficacy of treatment. A deeper understanding of treatment-induced accelerated aging in individuals with cancer may lead to novel strategies that reduce the accelerated aging and improve the quality of life in cancer survivors.

Immunosenescence in Testicular Cancer Survivors: Potential Implications of Cancer Therapies and Psychological Distress

Testicular cancer (TC) is the most frequent solid tumor diagnosed in young adult males. Although it is a curable tumor, it is frequently associated with considerable short-term and long-term morbidity. Both biological and psychological stress experienced during cancer therapy may be responsible for stimulating molecular processes that induce premature aging and deterioration of immune system (immunosenescence) in TC survivors, leading to an increased susceptibility to infections, cancer, and autoimmune diseases. Immunosenescence is a remodeling of immune cell populations with inversion of the CD4:CD8 ratio, accumulation of highly differentiated memory cells, shrinkage of telomeres, shift of T-cell response to Th2 type, and release of pro-inflammatory signals. TC survivors exposed to chemotherapy show features of immunological aging, including an increase in memory T-cells (CD4+ and CD8+) and high expression of the senescence biomarker p16INK4a in CD3+ lymphocytes. However, the plethora of factors involved in the premature aging of TC survivors make the situation more complex if we also take into account the psychological stress and hormonal changes experienced by patients, as well as the high-dose chemotherapy and hematopoietic stem cell transplantation that some individuals may be required to undergo. The relatively young age and the long life expectancy of TC patients bear witness to the importance of improving quality of life and of alleviating long-term side-effects of cancer treatments. Within this context, the present review takes an in-depth look at the molecular mechanisms of immunosenescence, describing experimental evidence of cancer survivor aging and highlighting the interconnected relationship between the many factors modulating the aging of the immune system of TC survivors.