Shani Alston

Cellular Senescence Promotes Adverse Effects of Chemotherapy and Cancer Relapse

Cellular senescence suppresses cancer by irreversibly arresting cell proliferation. Senescent cells acquire a proinflammatory senescence-associated secretory phenotype. Many genotoxic chemotherapies target proliferating cells nonspecifically, often with adverse reactions. In accord with prior work, we show that several chemotherapeutic drugs induce senescence of primary murine and human cells. Using a transgenic mouse that permits tracking and eliminating senescent cells, we show that therapy-induced senescent (TIS) cells persist and contribute to local and systemic inflammation. Eliminating TIS cells reduced several short- and long-term effects of the drugs, including bone marrow suppression, cardiac dysfunction, cancer recurrence, and physical activity and strength. Consistent with our findings in mice, the risk of chemotherapy-induced fatigue was significantly greater in humans with increased expression of a senescence marker in T cells prior to chemotherapy. These findings suggest that senescent cells can cause certain chemotherapy side effects, providing a new target to reduce the toxicity of anticancer treatments. SIGNIFICANCE Many genotoxic chemotherapies have debilitating side effects and also induce cellular senescence in normal tissues. The senescent cells remain chronically present where they can promote local and systemic inflammation that causes or exacerbates many side effects of the chemotherapy. Cancer Discov; 7(2); 165-76. ©2016 AACR.This article is highlighted in the In This Issue feature, p. 115.

Effect of Cytotoxic Chemotherapy on Markers of Molecular Age in Patients With Breast Cancer

BACKGROUND Senescent cells, which express p16 (INK4a) , accumulate with aging and contribute to age-related pathology. To understand whether cytotoxic agents promote molecular aging, we measured expression of p16 (INK4a) and other senescence markers in breast cancer patients treated with adjuvant chemotherapy. METHODS Blood and clinical information were prospectively obtained from 33 women with stage I to III breast cancer at four time points: before anthracycline-based chemotherapy, immediately after anthracycline-based chemotherapy, 3 months after anthracycline-based chemotherapy, and 12 months after anthracycline-based chemotherapy. Expression of senescence markers p16 (INK4a) and ARF mRNA was determined using TaqMan quantitative reverse-transcription polymerase chain reaction in CD3(+) T lymphocytes, telomere length was determined by Southern analysis, and senescence-associated cytokines were determined by enzyme-linked immunosorbent assay. Findings were independently assessed in a cross-sectional cohort of 176 breast cancer survivors enrolled a median of 3.4 years after treatment; 39% previously received chemotherapy. All statistical tests were two-sided. RESULTS In prospectively analyzed patients, expression of p16 (INK4a) and ARF increased immediately after chemotherapy and remained elevated 12 months after treatment. Median increase in log2 p16 (INK4a) was 0.81 (interquartile range = 0.28-1.62; Wilcoxon signed-rank P < .001), or a 75% absolute increase in expression, equivalent to the increase observed over 14.7 years of chronological aging. ARF expression was comparably increased (P < .001). Increased expression of p16 (INK4a) and ARF was associated with dose-dense therapy and hematological toxicity. Expression of two senescence-associated cytokines (VEGFA and MCP1) was durably increased by adjuvant chemotherapy. Telomere length was not affected by chemotherapy. In a cross-sectional cohort, prior chemotherapy exposure was independently associated with a log2-increase in p16 (INK4a) expression of 0.57 (repeated measures model, P < .001), comparable with 10.4 years of chronological aging. CONCLUSIONS Adjuvant chemotherapy for breast cancer is gerontogenic, inducing cellular senescence in vivo, thereby accelerating molecular aging of hematopoietic tissues.

Geriatric Assessment-Identified Deficits in Older Cancer Patients With Normal Performance Status

BACKGROUND We investigated whether a brief geriatric assessment (GA) would identify important patient deficits that could affect treatment tolerance and care outcomes within a sample of older cancer patients rated as functionally normal (80%-100%) on the Karnofsky performance status (KPS) scale. METHODS Cancer patients aged ≥65 years were assessed using a brief GA that included both professionally and patient-scored KPS and measures of comorbidity, polypharmacy, cognition, function, nutrition, and psychosocial status. Data were analyzed using descriptive statistics and multivariable logistic regression. RESULTS The sample included 984 patients: mean age was 73 years (range: 65-99 years), 74% were female, and 89% were white. GA was conducted before (23%), during (41%), or after (36%) treatment. Overall, 54% had a breast cancer diagnosis (n = 528), and 46% (n = 456) had cancers at other sites. Moreover, 81% of participants (n = 796) had both professionally and self-rated KPS ≥80, defined as functionally normal, and those patients are the focus of analysis. In this subsample, 550 (69%) had at least 1 GA-identified deficit, 222 (28%) had 1 deficit, 140 (18%) had 2 deficits, and 188 (24%) had ≥3 deficits. Specifically, 43% reported taking ≥9 medications daily, 28% had decreased social activity, 25% had ≥4 comorbidities, 23% had ≥1 impairment in instrumental activities of daily living, 18% had a Timed Up and Go time ≥14 seconds, 18% had ≥5% unintentional weight loss, and 12% had a Mental Health Index score ≤76. CONCLUSION Within this sample of older cancer patients who were rated as functionally normal by KPS, GA identified important deficits that could affect treatment tolerance and outcomes.

Feasibility of geriatric assessment in community oncology clinics.

OBJECTIVE Emerging results support the value of geriatric assessment (GA) in determining the risk and benefits of cancer treatment in older adults. A brief GA tool consisting of valid and reliable measures has been developed; however, little data exist on the ability to perform the GA in community oncology clinics. The objective of this study was to determine the feasibility of performing the GA in the community. MATERIALS AND METHODS Patients aged ≥65 were eligible. The GA included a health care provider assessment of performance status, cognitive function, a Timed Up and Go test, and a self-administered patient questionnaire that evaluated measures of functional status, comorbidity, psychological state, social support, and nutritional status. RESULTS From 2009 to 2013, 1088 patients were assessed including 339 (31%) from seven community clinics across North Carolina. The median amount of time to complete the patient-report portion of the GA was 19min in the academic center versus 22min in the community. The median amount of time to complete the entire GA was 23min in the academic center and 30min in community settings. Significantly more patients in the community required assistance completing the questionnaire (24% vs. 14%); however, most patients required no assistance (76%). CONCLUSION A brief GA can be performed in community oncology clinics. The time to complete the professional assessments and patient self-assessments were similar in both settings. Future studies are planned to determine if such assessments can improve cancer care for older patients.

Prevalence of sarcopenia in older patients with colorectal cancer

OBJECTIVE Sarcopenia is the age-related loss of muscle mass, strength, and function. It is a common finding in older patients and is associated with decreased life expectancy and potentially higher susceptibility to chemotherapy toxicity. This study describes the prevalence of sarcopenia in older adults with early stage colorectal cancer. MATERIALS AND METHODS Patients ≥70 years old who underwent surgical resection for stage I-III colorectal cancer between 2008 and 2013 were identified from the medical record. Sarcopenia was assessed by measuring the total muscle area on computerized tomography (CT) images obtained prior to surgery. Total muscle area was measured at the level of L3 and normalized using each patients height to produce a skeletal muscle index (SMI). Sarcopenia was defined using sex- and body mass index (BMI)-specific threshold values of SMI. RESULTS Eighty-seven patients were included, with a median age of 77 years (70-96). Twenty-five men (60% of 42) and 25 women (56% of 45) had sarcopenia. Sarcopenic patients had significantly lower BMI (p=0.03) compared to non-sarcopenic patients. There was a positive correlation between BMI and SMI for both men (r=0.44) and women (r=0.16). CONCLUSION Sarcopenia is highly prevalent among older patients with early stage colorectal cancer. BMI alone is a poor indicator of lean body mass and improved methods of screening for sarcopenia are necessary. CT scans are a viable option for identifying sarcopenic patients in whom timely interventions may improve survival, quality of life, and functional outcomes.

Patient engagement and study design of PROP UP: A multi-site patient-centered prospective observational study of patients undergoing hepatitis C treatment

BACKGROUND New highly efficacious direct-acting antiviral (DAA) therapies are available to treat chronic hepatitis C viral (HCV) infection. Real-world, patient-centered data on harms and benefits associated with these therapies are needed. METHODS PROP UP is a multi-center prospective observational study that plans to enroll 1600 patients starting treatment with recently-approved DAA regimens. Informed by extensive input from a HCV patient engagement group who prioritized outcomes most important to them, patient-reported outcomes will be characterized using surveys at five time points: Baseline (T1), treatment week 4 (T2), end of treatment (T3), 12weeks post-treatment (T4), 12months post-treatment (T5). OUTCOMES (1) Changes in side effects, functioning, pre-existing conditions, and out-of-pocket costs during therapy (T1 vs T2/T3); (2) Medication adherence in relation to a history of mental health/substance abuse, treatment regimens, pill burden, reasons for missed doses, and cure rates; (3) Short term impact of cure on functioning and amelioration of symptoms (T1 vs T4); (4) Long-term treatment harms or benefits of cure on symptoms, side effects, pre-existing conditions, and functioning (T1 vs T5). Similarities between regimens will be examined where comparisons are appropriate and meaningful. CONCLUSION PROP UP complements previous clinical trials by focusing on patient-reported outcomes in a representative sample of patients treated in clinical practice, by collaborating with a patient engagement group, by characterizing the experiences of vulnerable subgroups, and by investigating long-term harms and benefits of treatments. PROP UP is designed to provide novel and detailed information to support informed decision-making for patients and providers contemplating HCV treatment (PCORI CER-1408-20,660; NCT02601820).

Beyond sarcopenia: Characterization and integration of skeletal muscle quantity and radiodensity in a curable breast cancer population

Skeletal muscle loss, commonly known as sarcopenia, is highly prevalent and prognostic of adverse outcomes in oncology. However, there is limited information on adults with early breast cancer and examination of other skeletal muscle indices, despite the potential prognostic importance. This study characterizes and examines age‐related changes in body composition of adults with early breast cancer and describes the creation of a novel integrated muscle measure. Female patients diagnosed with stage I‐III breast cancer with abdominal computerized tomography (CT) scans within 12 weeks from diagnosis were identified from local tumor registry (N = 241). Skeletal muscle index (muscle area per height [cm2/m2]), skeletal muscle density, and subcutaneous and visceral adipose tissue areas, were determined from CT L3 lumbar segments. We calculated a novel integrated skeletal measure, skeletal muscle gauge, which combines skeletal muscle index and density (SMI × SMD). 241 patients were identified with available CT imaging. Median age 52 years and range of 23‐87. Skeletal muscle index and density significantly decreased with age. Using literature based cut‐points, older adults (≥65 years) had significantly higher proportions of sarcopenia (63 vs 28%) and myosteatosis (90 vs 11%) compared to younger adults (<50 years). Body mass index was positively correlated with skeletal muscle index and negatively correlated with muscle density. Skeletal muscle gauge correlated better with increasing age (ρ = 0.52) than with either skeletal muscle index (ρ = 0.20) or density (ρ = 0.46). Wide variations and age‐related changes in body composition metrics were found using routinely obtained abdominal CT imaging. Skeletal muscle index and density provide independent, complementary information, and the product of the two metrics, skeletal muscle gauge, requires further research to explore its impact on outcomes in women with curable breast cancer.