Accelerated aging in older cancer survivors

A scoping review evaluating physical and cognitive functional outcomes in cancer survivors treated with chemotherapy: charting progress since the 2018 NCI think tank on cancer and aging phenotypes

PURPOSE

The primary goal of this scoping review was to summarize the literature published after the 2018 National Cancer Institute think tank, "Measuring Aging and Identifying Aging Phenotypes in Cancer Survivors," on physical and cognitive functional outcomes among cancer survivors treated with chemotherapy. We focused on the influence of chemotherapy on aging-related outcomes (i.e., physical functional outcomes, cognitive functional outcomes, and frailty), given the known associations between chemotherapy and biologic mechanisms that affect aging-related physiologic processes.

METHODS

A search was conducted across electronic databases, including PubMed, Scopus, and Web of Science, for manuscripts published between August 2018 and July 2023. Eligible studies: 1) included physical function, cognitive function, and/or frailty as outcomes; 2) included cancer survivors (as either the whole sample or a subgroup); 3) reported on physical or cognitive functional outcomes and/or frailty related to chemotherapy treatment (as either the whole sample or a subgroup); and 4) were observational in study design.

RESULTS

The search yielded 989 potentially relevant articles, of which 65 met the eligibility criteria. Of the 65 studies, 49 were longitudinal, and 16 were cross-sectional; 30 studies (46%) focused on breast cancer, 20 studies (31%) focused on the age group 60 + years, and 17 (26%) focused on childhood cancer survivors. With regards to outcomes, 82% of 23 studies reporting on physical function showed reduced physical function, 74% of 39 studies reporting on cognitive functional outcomes found reduced cognitive function, and 80% of 15 studies reporting on frailty found increasing frailty among cancer survivors treated with chemotherapy over time and/or compared to individuals not treated with chemotherapy. Fourteen studies (22%) evaluated biologic mechanisms and their relationship to aging-related outcomes. Inflammation was consistently associated with worsening physical and cognitive functional outcomes and epigenetic age increases. Further, DNA damage was consistently associated with worse aging-related outcomes.

CONCLUSION

Chemotherapy is associated with reduced physical function, reduced cognitive function, and an increase in frailty in cancer survivors; these associations were demonstrated in longitudinal and cross-sectional studies. Inflammation and epigenetic age acceleration are associated with worse physical and cognitive function; prospective observational studies with multiple time points are needed to confirm these findings.

IMPLICATIONS FOR CANCER SURVIVORS

This scoping review highlights the need for interventions to prevent declines in physical and cognitive function in cancer survivors who have received chemotherapy.

Functional decline in older breast cancer survivors treated with and without chemotherapy and non-cancer controls: results from the Hurria Older PatiEnts (HOPE) prospective study

PURPOSE

This study aimed to assess whether physical functional decline in older women with early-stage breast cancer is driven by cancer, chemotherapy, or a combination of both.

METHODS

We prospectively sampled three groups of women aged ≥ 65: 444 with early-stage breast cancer receiving chemotherapy (BC Chemo), 98 with early-stage breast cancer not receiving chemotherapy (BC Control), and 100 non-cancer controls (NC Control). Physical function was assessed at two timepoints (T1 [baseline] and T2 [3, 4, or 6 months]) using the Physical Functioning Subscale (PF-10) of the RAND 36-item Short Form. The primary endpoint was the change in PF-10 scores from T1 to T2, analyzed continuously and dichotomously (Yes/No, with "yes" indicating a PF-10 decline > 10 points, i.e., a substantial and clinically meaningful difference).

RESULTS

Baseline PF-10 scores were similar across all groups. The BC Chemo group experienced a significant decline at T2, with a median change in PF-10 of -5 (interquartile range [IQR], -20, 0), while BC Control and NC Control groups showed a median change of 0 (IQR, -5, 5; p < 0.001). Over 30% of BC Chemo participants had a substantial decline in PF-10 vs. 8% in the BC Control and 5% in the NC Control groups (p < 0.001).

CONCLUSION

In this cohort of older adults with early-stage breast cancer, the combination of breast cancer and chemotherapy contributes to accelerated functional decline. Our findings reinforce the need to develop interventions aimed at preserving physical function, particularly during and after chemotherapy.

IMPLICATIONS FOR CANCER SURVIVORS

The high prevalence of accelerated functional decline in older women undergoing breast cancer chemotherapy underscores the urgency to develop interventions aimed at preserving physical function and improving health outcomes.

CLINICAL TRIAL

NCT01472094, Hurria Older PatiEnts (HOPE) with Breast Cancer Study.

Enhancing Mobility and Well-Being in Older Adults with Cancer

OBJECTIVE

To analyze mobility challenges in older adult with cancer.

METHODS

Data from previous literature was extracted and analyzed pertaining to the topic of interest.

RESULTS

Mobility issues for the older adult with cancer are multi-factorial and are impacted by age-related changes, comorbidities, cancer itself, and cancer treatment.

CONCLUSIONS

Proven benefits have been suggested with mobility assessments, exercise and dietary interventions, and cancer rehabilitation programs however further research is needed to define integration and utilization of programs, facilitation of cancer survivors returning to work, inclusion of socially disadvantaged patients, program compliance, economic aspects, and caregiver involvement to improve quality of life across the cancer continuum.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses are in a key role to impact the care of the older adult with cancer with mobility through patient assessment of mobility function, facilitation of patient referrals for supportive services and cancer rehabilitation and execution of nurse-led intervention programs.

Health-related conditions among long-term cancer survivors diagnosed in adolescence and young adulthood (AYA): results of the SURVAYA study

BACKGROUND

With 5-year survival rates > 85%, gaining insight into the long-term and late health-related conditions of cancer survivors diagnosed in adolescence and young adulthood is of utmost importance to improve their quantity and quality of survival. This study examined the prevalence of and factors associated with, patient-reported health-related conditions and their latency times among long-term adolescent and young adult (AYA) cancer survivors.

METHODS

AYA cancer survivors (5-20 years after diagnosis) were identified by the population-based Netherlands Cancer Registry (NCR), and invited to participate in the SURVAYA questionnaire study. Participants reported the prevalence and date of diagnosis of health-related conditions. Clinical data were retrieved from the NCR.

RESULTS

Three thousand seven hundred seventy-six AYA cancer survivors (response rate 33.4%) were included for analyses. More than half of the AYAs (58.5%) experienced health-related conditions after their cancer diagnosis, of whom 51.4% were diagnosed with two or more conditions. Participants reported conditions related to vision (15.0%), digestive system (15.0%), endocrine system (14.1%), cardiovascular system (11.7%), respiratory system (11.3%), urinary tract system (10.9%), depression (8.6%), hearing (7.4%), arthrosis (6.9%), secondary malignancy (6.4%), speech-, taste and smell (4.5%), and rheumatoid arthritis (2.1%). Time since diagnosis, tumor type, age at diagnosis, and educational level were most frequently associated with a health-related condition.

CONCLUSIONS

A significant proportion of long-term AYA cancer survivors report having one or more health-related conditions.

IMPLICATIONS FOR CANCER SURVIVORS

Future research should focus on better understanding the underlying mechanisms of, and risk factors for, these health-related conditions to support the development and implementation of risk-stratified survivorship care for AYA cancer survivors to further improve their outcomes.

CLINICAL TRIALS REGISTRATION

NCT05379387.

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.

Feasibility of a Health Coach Intervention to Reduce Sitting Time and Improve Physical Functioning Among Breast Cancer Survivors: Pilot Intervention Study

BACKGROUND

Sedentary behavior among breast cancer survivors is associated with increased risk of poor physical function and worse quality of life. While moderate to vigorous physical activity can improve outcomes for cancer survivors, many are unable to engage in that intensity of physical activity. Decreasing sitting time may be a more feasible behavioral target to potentially mitigate the impact of cancer and its treatments.

OBJECTIVE

The purpose of this study was to investigate the feasibility and preliminary impact of an intervention to reduce sitting time on changes to physical function and quality of life in breast cancer survivors, from baseline to a 3-month follow-up.

METHODS

Female breast cancer survivors with self-reported difficulties with physical function received one-on-one, in-person personalized health coaching sessions aimed at reducing sitting time. At baseline and follow-up, participants wore the activPAL (thigh-worn accelerometer; PAL Technologies) for 3 months and completed physical function tests (4-Meter Walk Test, Timed Up and Go, and 30-Second Chair Stand) and Patient-Reported Outcomes Measurement Information System (PROMIS) self-reported outcomes. Changes in physical function and sedentary behavior outcomes were assessed by linear mixed models.

RESULTS

On average, participants (n=20) were aged 64.5 (SD 9.4) years; had a BMI of 30.4 (SD 4.5) kg/m2; and identified as Black or African American (n=3, 15%), Hispanic or Latina (n=4, 20%), and non-Hispanic White (n=14, 55%). Average time since diagnosis was 5.8 (SD 2.2) years with participants receiving chemotherapy (n=8, 40%), radiotherapy (n=18, 90%), or endocrine therapy (n=17, 85%). The intervention led to significant reductions in sitting time: activPAL average daily sitting time decreased from 645.7 (SD 72.4) to 532.7 (SD 142.1; β=-112.9; P=.001) minutes and average daily long sitting bouts (bout length ≥20 min) decreased from 468.3 (SD 94.9) to 366.9 (SD 150.4; β=-101.4; P=.002) minutes. All physical function tests had significant improvements: on average, 4-Meter Walk Test performance decreased from 4.23 (SD 0.95) to 3.61 (SD 2.53; β=-.63; P=.002) seconds, Timed Up and Go performance decreased from 10.30 (SD 3.32) to 8.84 (SD 1.58; β=-1.46; P=.003) seconds, and 30-Second Chair Stand performance increased from 9.75 (SD 2.81) to 13.20 completions (SD 2.53; β=3.45; P<.001). PROMIS self-reported physical function score improved from 44.59 (SD 4.40) to 47.12 (SD 5.68; β=2.53; P=.05) and average fatigue decreased from 52.51 (SD 10.38) to 47.73 (SD 8.43; β=-4.78; P=.02).

CONCLUSIONS

This 3-month pilot study suggests that decreasing time spent sitting may be helpful for breast cancer survivors experiencing difficulties with physical function and fatigue. Reducing sitting time is a novel and potentially more feasible approach to improving health and quality of life in cancer survivors.

Post-traumatic stress disorder symptoms and quality of life among older patients with cancer during the COVID-19 pandemic

INTRODUCTION

The Coronavirus (COVID-19) pandemic and its associated health restrictions have harmed the population psychologically. We aimed to compare the post-traumatic stress disorder (PTSD) symptoms and Quality of Life (QoL) in older French patients with cancer to the younger ones.

MATERIALS AND METHODS

This longitudinal multicenter study named COVIPACT began in April 2020 during the first French lockdown and has included 579 outpatients receiving treatment for a solid or hematological malignancy. Data were collected every three months, namely at the first release period (M3), at the second lockdown (M6), at the second release period (M9), and finally at the last curfew period (M12) in France. Standardized validated self-questionnaires were used to assess PTSD symptoms (using the Event Scale-Revised self-questionnaire), insomnia (through the Insomnia Severity Index questionnaire), QoL (using the Functional Assessment of Cancer Therapy - General questionnaire), and cognitive complaints (through the Functional Assessment of Cancer Therapy - Cognition questionnaire). Student (or Wilcoxon) tests and Chi-squared tests were used for continuous or discrete variables, respectively. We conducted linear mixed model to study the change during follow-up.

RESULTS

Out of 579 included patients, 157 (27%) were ≥ 70 years old at baseline, of whom 104 participated in the longitudinal study. At baseline, older patients reported fewer PTSD symptoms (17% versus 23%, p = .06), insomnia (17% versus 27%, p = .02), and cognitive complaint (3% versus 16%, p < .01) than younger patients. QoL at baseline was similar between age subgroups. We observed no significant difference in the trajectory of PTSD symptoms, insomnia, or emotional well-being between both groups during the follow-up. Cognitive complaints were lower at baseline in older patients but steadily increased during the follow-up and reached the same level as younger patients at one year.

DISCUSSION

One in five older patients reported PTSD symptoms, evolving similarly to younger patients during the first year of the COVID-19 pandemic. While cognitive complaints tend to recover in a bell-shaped curve at one year in younger patients, the trend is increasing in older ones. Screening for PTSD symptoms and late cognitive impairment should be given special attention in older patients.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT04366154.

Heterogeneity of financial toxicity and associated risk factors for older cancer survivors in China

In China, older cancer survivors may show heterogeneity in financial toxicity (FT). We aimed to identify FT profiles among older Chinese cancer survivors and examine the association between FT profiles and individual characteristics. We used a latent profile analysis to categorize participants and a multinomial logistic regression to examine the associations. We identified three distinct FT profiles: high, moderate, and low. Participants aged 65-69 years, with a monthly household income ≥ 5,000 CNY and a high school education or above were more likely to be classified into the moderate than high FT profile, a monthly household income ≥ 5,000 CNY increased the likelihood of being in the low FT profile and living alone negatively affected the odds of being in the low FT profile. The findings identified heterogeneity in FT among this population, may help identify high-risk groups, and may enable early intervention.

Exercise effects on functional capacity and quality of life in older patients with colorectal cancer: study protocol for the ECOOL randomized controlled trial

BACKGROUND

Surgery and treatment for colorectal cancer (CRC) in the elderly patient increase the risk of developing post-operative complications, losing functional independence, and worsening health-related quality of life (HRQoL). There is a lack of high-quality randomized controlled trials evaluating the potential benefit of exercise as a countermeasure. The primary aim of this study is to evaluate the effectiveness of a home-based multicomponent exercise program for improving HRQoL and functional capacity in older adults undergoing CRC surgery and treatment.

METHODS

This randomized, controlled, observer-blinded, single-center trial aims to randomize 250 patients (>74 years) to either an intervention or a control group (i.e., usual care). The intervention group will perform an individualized home-based multicomponent exercise program with weekly telephone supervision from diagnosis until three months post-surgery. The primary outcomes will be HRQoL (EORTC QLQ-C30; CR29; and ELD14) and functional capacity (Barthel Index and Short Physical Performance Battery), which will be assessed at diagnosis, at discharge, and one, three, and six months after surgery. Secondary outcomes will be frailty, physical fitness, physical activity, inspiratory muscle function, sarcopenia and cachexia, anxiety and depression, ambulation ability, surgical complications, and hospital length of stay, readmission and mortality.

DISCUSSION

This study will examine the effects of an exercise program in older patients with CRC across a range of health-related outcomes. Expected findings are improvement in HRQoL and physical functioning. If proven effective, this simple exercise program may be applied in clinical practice to improve CRC care in older patients.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT05448846.

Immunotherapeutic approach to reduce senescent cells and alleviate senescence-associated secretory phenotype in mice

Accumulation of senescent cells (SNCs) with a senescence-associated secretory phenotype (SASP) has been implicated as a major source of chronic sterile inflammation leading to many age-related pathologies. Herein, we provide evidence that a bifunctional immunotherapeutic, HCW9218, with capabilities of neutralizing TGF-β and stimulating immune cells, can be safely administered systemically to reduce SNCs and alleviate SASP in mice. In the diabetic db/db mouse model, subcutaneous administration of HCW9218 reduced senescent islet β cells and SASP resulting in improved glucose tolerance, insulin resistance, and aging index. In naturally aged mice, subcutaneous administration of HCW9218 durably reduced the level of SNCs and SASP, leading to lower expression of pro-inflammatory genes in peripheral organs. HCW9218 treatment also reverted the pattern of key regulatory circadian gene expression in aged mice to levels observed in young mice and impacted genes associated with metabolism and fibrosis in the liver. Single-nucleus RNA Sequencing analysis further revealed that HCW9218 treatment differentially changed the transcriptomic landscape of hepatocyte subtypes involving metabolic, signaling, cell-cycle, and senescence-associated pathways in naturally aged mice. Long-term survival studies also showed that HCW9218 treatment improved physical performance without compromising the health span of naturally aged mice. Thus, HCW9218 represents a novel immunotherapeutic approach and a clinically promising new class of senotherapeutic agents targeting cellular senescence-associated diseases.

Association of frailty with the incidence risk of cardiovascular disease and type 2 diabetes mellitus in long-term cancer survivors: a prospective cohort study

BACKGROUND

Comorbidities among cancer survivors remain a serious healthcare burden and require appropriate management. Using two widely used frailty indicators, this study aimed to evaluate whether frailty was associated with the incidence risk of cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) among long-term cancer survivors.

METHODS

We included 13,388 long-term cancer survivors (diagnosed with cancer over 5 years before enrolment) free of CVD and 6101 long-term cancer survivors free of T2DM, at the time of recruitment (aged 40-69 years), from the UK Biobank. Frailty was assessed by the frailty phenotype (FP_Frailty, range: 0-5) and the frailty index (FI_Frailty, range: 0-1) at baseline. The incident CVD and T2DM were ascertained through linked hospital data and primary care data, respectively. The associations were examined using Cox proportional hazards regression models.

RESULTS

Compared with non-frail participants, those with pre-frailty (FP_Frailty [met 1-2 of the components]: hazard ratio [HR]=1.18, 95% confidence interval [CI]: 1.05, 1.32; FI_Frailty [0.10< FI ≤0.21]: HR=1.51, 95% CI: 1.32, 1.74) and frailty (FP_Frailty [met ≥3 of the components]: HR=2.12, 95% CI: 1.73, 2.60; FI_Frailty [FI >0.21]: HR=2.19, 95% CI: 1.85, 2.59) had a significantly higher risk of CVD in the multivariable-adjusted model. A similar association of FI_Frailty with the risk of incident T2DM was observed. We failed to find such an association for FP_Frailty. Notably, the very early stage of frailty (1 for FP_Frailty and 0.1-0.2 for FI_Frailty) was also positively associated with the risk of CVD and T2DM (FI_Frailty only). A series of sensitivity analyses confirmed the robustness of the findings.

CONCLUSIONS

Frailty, even in the very early stage, was positively associated with the incidence risk of CVD and T2DM among long-term cancer survivors, although discrepancies existed between frailty indicators. While the validation of these findings is required, they suggest that routine monitoring, prevention, and interventive programs of frailty among cancer survivors may help to prevent late comorbidities and, eventually, improve their quality of life. Especially, interventions are recommended to target those at an early stage of frailty when healthcare resources are limited.

Low-Intensity Adjuvant Chemotherapy for Breast Cancer in Older Women: Results From the Prospective Multicenter HOPE Trial

PURPOSE

Older women with high-risk early breast cancer (EBC) benefit from adjuvant chemotherapy, but their treatment is frequently complicated by toxic side effects, resulting in dose reductions and delays. This makes it challenging for oncologists to maintain a relative dose intensity (RDI) ≥ 85%, as recommended for optimal curative-intent treatment. Understanding which women are at risk of receiving suboptimal RDI may inform treatment discussions and guide early, targeted supportive care or geriatric comanagement interventions.

METHODS

This was a prespecified secondary analysis of the HOPE trial, which enrolled women age ≥ 65 years with EBC initiating neoadjuvant or adjuvant chemotherapy. RDI was calculated as the ratio of delivered to planned chemotherapy dose intensity. The primary outcome was low RDI, defined as RDI < 85%. Multivariable logistic regression with stepwise selection was used to evaluate the association between baseline variables (demographic, clinical, and geriatric assessment) and low RDI. Survival probability was estimated using the Kaplan-Meier method, and the log-rank test was used to compare overall survival.

RESULTS

Three hundred twenty-two patients (median age at diagnosis, 70 years; range, 65-86 years) were included. The median follow-up was 4 years. Sixty-six patients (21%) had a low RDI. Age ≥ 76 years (odds ratio [OR], 2.57; 95% CI, 1.12 to 5.91; P = .03), lower performance status (OR, 4.32; 95% CI, 1.98 to 9.42; P < .001), and use of anthracycline-based or cyclophosphamide, methotrexate, and fluorouracil regimens (OR, 3.47; 95% CI, 1.71 to 7.05; P < .001) were associated with low RDI. The 5-year overall survival probability was 0.80 versus 0.91 in patients with RDI < 85 versus ≥ 85%, respectively (log-rank P = .02).

CONCLUSION

One in five older patients with EBC treated with standard chemotherapy received low RDI and had inferior survival outcomes. Older patients at risk for low RDI should be identified and targeted upfront before initiating chemotherapy.

Inflammation and Clinical Decline After Adjuvant Chemotherapy in Older Adults With Breast Cancer: Results From the Hurria Older Patients Prospective Study

PURPOSE

Older breast cancer survivors are at increased risk of clinical decline after adjuvant chemotherapy. This study aimed to evaluate whether inflammatory markers assessed before adjuvant chemotherapy are associated with chemotherapy-induced clinical decline in a population of fit older adults with breast cancer.

METHODS

In a prospective study of women age ≥ 65 years with stage I-III breast cancer treated with chemotherapy, we measured interleukin-6 (IL-6) and C-reactive protein (CRP) prechemotherapy (T1). We assessed frailty status, using a Deficit Accumulation Index (DAI; categorized as robust, prefrail, and frail), at T1 and postchemotherapy (T2). The population of interest was robust women at T1. The primary outcome was chemotherapy-induced decline in frailty status, defined as decline in DAI from robust (T1) to prefrail or frail (T2). Multivariable logistic regression was used to examine the association between inflammatory markers and the primary outcome, adjusted for sociodemographic and clinical characteristics.

RESULTS

Of the 295 robust women at T1, 76 (26%) experienced chemotherapy-induced decline in frailty status, among whom 66% had high IL-6, 63% had high CRP, and 46% had high IL-6 and CRP at T1. After adjusting for sociodemographic and clinical characteristics, women with high IL-6 and CRP had a > three-fold (odds ratio, 3.52; 95% CI, 1.55 to 8.01; P = .003) odds of chemotherapy-induced decline in frailty status compared with women with low IL-6 and CRP.

CONCLUSION

In this cohort of older women with early breast cancer who were clinically fit before chemotherapy initiation, high IL-6 and CRP prechemotherapy were associated with chemotherapy-induced decline in frailty status independent of sociodemographic and clinical risk factors. Further research is needed to examine whether inflammatory markers can inform more personalized approaches to treating older breast cancer survivors.

A Longitudinal Examination of the Association Between Loss of Control and Loneliness Among Older Adults Diagnosed with Cancer

Objectives: The objective of this paper is to examine whether feeling a loss of control over one's life is associated with an increased risk for loneliness among those diagnosed with cancer. Method: We draw on data from the Health and Retirement Study to identify three baseline and follow-up cohorts of cancer survivors age 50 and older. Ordinary least squared regression is used to examine predictors for future loneliness. Results: Upon adjusting for other known predictors of loneliness, feelings of loss of control was significantly predictive of loneliness among 4-year cancer survivors. Discussion: Social workers and other health care practitioners should seek to provide evidence-based interventions to reduce the risk for loneliness for cancer survivors feeling a loss of control.

Frailty-the missing constraint in radiotherapy treatment planning for older adults

Current demographic changes translate into an increased frequency of cancer in older adults. Available data show that about 45-55% of the new cancer patients will need RT treatments, with an expected increase of 20-30% in the future. To provide the best cancer care it is mandatory to assess frailty, offer appropriate curative treatments to patients and personalise them for the frail. Based on published data, the median prevalence of frailty in older population is about 42%. Recently, the free radical theory of frailty has been proposed stating that oxidative damage is more prevalent in frail patients. In parallel, RT is one of the most frequent cancer treatments offered to older adults and is a source of external free radicals. RT dose constraints correlate with toxicity rates, so we open the question whether frailty should be considered when defining these constraints. Thus, for this paper, we will highlight the importance of frailty evaluation for RT treatment decisions and outcomes.

Cancer treatment-induced NAD+ depletion in premature senescence and late cardiovascular complications

Numerous studies have revealed the critical role of premature senescence induced by various cancer treatment modalities in the pathogenesis of aging-related diseases. Senescence-associated secretory phenotype (SASP) can be induced by telomere dysfunction. Telomeric DNA damage response induced by some cancer treatments can persist for months, possibly accounting for long-term sequelae of cancer treatments. Telomeric DNA damage-induced mitochondrial dysfunction and increased reactive oxygen species production are hallmarks of premature senescence. Recently, we reported that the nucleus-mitochondria positive feedback loop formed by p90 ribosomal S6 kinase (p90RSK) and phosphorylation of S496 on ERK5 (a unique member of the mitogen-activated protein kinase family that is not only a kinase but also a transcriptional co-activator) were vital signaling events that played crucial roles in linking mitochondrial dysfunction, nuclear telomere dysfunction, persistent SASP induction, and atherosclerosis. In this review, we will discuss the role of NAD⁺ depletion in instigating SASP and its downstream signaling and regulatory mechanisms that lead to the premature onset of atherosclerotic cardiovascular diseases in cancer survivors.