Colorectal Cancer Cells Enter a Diapause-like DTP State to Survive Chemotherapy.

Cancer cells enter a reversible drug-tolerant persister (DTP) state to evade death from chemotherapy and targeted agents. It is increasingly appreciated that DTPs are important drivers of therapy failure and tumor relapse. We combined cellular barcoding and mathematical modeling in patient-derived colorectal cancer models to identify and characterize DTPs in response to chemotherapy. Barcode analysis revealed no loss of clonal complexity of tumors that entered the DTP state and recurred following treatment cessation. Our data fit a mathematical model where all cancer cells, and not a small subpopulation, possess an equipotent capacity to become DTPs. Mechanistically, we determined that DTPs display remarkable transcriptional and functional similarities to diapause, a reversible state of suspended embryonic development triggered by unfavorable environmental conditions. Our study provides insight into how cancer cells use a developmentally conserved mechanism to drive the DTP state, pointing to novel therapeutic opportunities to target DTPs.

DNA-Demethylating Agents Target Colorectal Cancer Cells by Inducing Viral Mimicry by Endogenous Transcripts.

DNA-demethylating agents have shown clinical anti-tumor efficacy via an unknown mechanism of action. Using a combination of experimental and bioinformatics analyses in colorectal cancer cells, we demonstrate that low-dose 5-AZA-CdR targets colorectal cancer-initiating cells (CICs) by inducing viral mimicry. This is associated with induction of dsRNAs derived at least in part from endogenous retroviral elements, activation of the MDA5/MAVS RNA recognition pathway, and downstream activation of IRF7. Indeed, disruption of virus recognition pathways, by individually knocking down MDA5, MAVS, or IRF7, inhibits the ability of 5-AZA-CdR to target colorectal CICs and significantly decreases 5-AZA-CdR long-term growth effects. Moreover, transfection of dsRNA into CICs can mimic the effects of 5-AZA-CdR. Together, our results represent a major shift in understanding the anti-tumor mechanisms of DNA-demethylating agents and highlight the MDA5/MAVS/IRF7 pathway as a potentially druggable target against CICs.

Epigenetic therapy induces transcription of inverted SINEs and ADAR1 dependency.

Cancer therapies that target epigenetic repressors can mediate their effects by activating retroelements within the human genome. Retroelement transcripts can form double-stranded RNA (dsRNA) that activates the MDA5 pattern recognition receptor1-6. This state of viral mimicry leads to loss of cancer cell fitness and stimulates innate and adaptive immune responses7,8. However, the clinical efficacy of epigenetic therapies has been limited. To find targets that would synergize with the viral mimicry response, we sought to identify the immunogenic retroelements that are activated by epigenetic therapies. Here we show that intronic and intergenic SINE elements, specifically inverted-repeat Alus, are the major source of drug-induced immunogenic dsRNA. These inverted-repeat Alus are frequently located downstream of 'orphan' CpG islands9. In mammals, the ADAR1 enzyme targets and destabilizes inverted-repeat Alu dsRNA10, which prevents activation of the MDA5 receptor11. We found that ADAR1 establishes a negative-feedback loop, restricting the viral mimicry response to epigenetic therapy. Depletion of ADAR1 in patient-derived cancer cells potentiates the efficacy of epigenetic therapy, restraining tumour growth and reducing cancer initiation. Therefore, epigenetic therapies trigger viral mimicry by inducing a subset of inverted-repeats Alus, leading to an ADAR1 dependency. Our findings suggest that combining epigenetic therapies with ADAR1 inhibitors represents a promising strategy for cancer treatment.

Denosumab in a pediatric kidney transplant recipient with late, resistant hypercalcemia secondary to Pneumocystis jirovecii pneumonia.

Kidney transplant recipients (KTR) are at an increased risk of developing Pneumocystis jirovecii pneumonia (PCP), especially during the first year after transplantation. This is the first reported pediatric KTR, with chronic kidney disease (CKD) secondary to kidney dysplasia and vesicoureteral reflux, who developed refractory and symptomatic hypercalcemia 5 years after transplantation. The hypercalcemia was resistant to treatment with intravenous hyperhydration, furosemide, and a low-calcium diet. A respiratory tract infection due to PCP treated with trimethoprim-sulfamethoxazole did not improve calcium levels. Due to the hypercalcemic symptom burden for the patient, a single dose of subcutaneous denosumab was used to achieve sustained clinical and biochemical improvement, without any severe adverse events. This case highlights the potential use of denosumab as a treatment option in pediatric KTR with refractory hypercalcemia related to PCP. Further study of denosumab in young people with CKD or kidney transplants is needed before routine use can be recommended.

Sensitive tumour detection and classification using plasma cell-free DNA methylomes.

The use of liquid biopsies for cancer detection and management is rapidly gaining prominence1. Current methods for the detection of circulating tumour DNA involve sequencing somatic mutations using cell-free DNA, but the sensitivity of these methods may be low among patients with early-stage cancer given the limited number of recurrent mutations2-5. By contrast, large-scale epigenetic alterations-which are tissue- and cancer-type specific-are not similarly constrained6 and therefore potentially have greater ability to detect and classify cancers in patients with early-stage disease. Here we develop a sensitive, immunoprecipitation-based protocol to analyse the methylome of small quantities of circulating cell-free DNA, and demonstrate the ability to detect large-scale DNA methylation changes that are enriched for tumour-specific patterns. We also demonstrate robust performance in cancer detection and classification across an extensive collection of plasma samples from several tumour types. This work sets the stage to establish biomarkers for the minimally invasive detection, interception and classification of early-stage cancers based on plasma cell-free DNA methylation patterns.

Oral antimicrobial therapy for cellulitis versus outpatient parenteral antimicrobial therapy: a single-centre audit of cellulitis outcomes.

BACKGROUND: Cellulitis is a common acute skin and soft tissue infection that causes substantial morbidity and healthcare costs. AIMS: To audit the impact on cellulitis management, regimen tolerability and outcomes of switching from outpatient parenteral antimicrobial therapy (OPAT) using intravenous (i.v.) cefazolin once daily plus probenecid to oral beta-lactam therapy (OBLT) using oral flucloxacillin plus probenecid. METHODS: We undertook a retrospective audit on cellulitis management, regimen tolerability and outcomes at the Dunedin Public Hospital Emergency Department (ED) before and after a change of the local outpatient cellulitis treatment pathway from OPAT using i.v. cefazolin once daily plus probenecid to OBLT using oral flucloxacillin plus probenecid. RESULTS: OPAT was used in 97/123 (78.9%) patients with cellulitis before compared to 1/70 (1.4%) after the pathway change (odds ratio (OR), 0.04, P < 0.01). OBLT was used in 26/123 (21.1%) patients with cellulitis before and 69/70 (98.6%) after (OR, 218.8, P < 0.01). Antimicrobial change due to intolerance occurred in 4/123 (3.2%) patients with cellulitis before and 4/70 (5.7%) after (OR, 1.8, P, not significant (NS)) the pathway change. Inpatient admission within 28 days occurred in 15/123 (12.2%) cellulitis patients before and 9/70 (12.9%) after (OR, 1.1, P, NS) the pathway change. CONCLUSIONS: Implementation of a change in outpatient cellulitis treatment pathway resulted in a significant change in prescribing practice. Our findings suggest that OBLT was both tolerable and had similar outcomes to OPAT.

A Longitudinal Study of Adherence among Cystic Fibrosis Patients: Associations with Gratitude Over the Course of One Year.

BACKGROUND: Daily airway clearance therapy (ACT) is a critical aspect of treatment in cystic fibrosis (CF), but poor adherence is a prominent concern. Identifying factors that might enhance or diminish adherence is a priority for treatment centers. Gratitude, a generalized tendency to notice and appreciate positive facets of experience, is a psychosocial resource that has commanded growing research interest. This longitudinal study examined whether gratitude at baseline was associated with ongoing or persistent ACT adherence over the course of a year. METHODS: Trait gratitude was evaluated at baseline using a validated measure, among adults receiving care at a regional CF treatment center. Self-reported adherence to ACT was assessed at baseline, 6 months, and 12 months using the Cystic Fibrosis Treatment Questionnaire. Average age of participants was 27.2 years, 45.5% were women, and 19.7% had severe disease. RESULTS: In multivariable logistic regression models that accounted for disease severity (Forced Expiratory Volume1% predicted) and other clinical and demographic variables, individuals with higher baseline gratitude were significantly more likely to demonstrate persistent adherence over the course of the year. Gratitude remained predictive after additionally adjusting for other well-known psychosocial resource variables (social support and emotional well-being). CONCLUSION: This is among the first demonstrations that gratitude is associated with persistent self-reported adherence to treatment over time. Findings suggest that gratitude may be important psychosocial resource for adults with CF, as they contend with complex, highly burdensome treatment regimens. Further research is warranted to examine these relationships and their impact on downstream health outcomes.

N6-Methyladenosine Reader YTHDF1 Promotes ARHGEF2 Translation and RhoA Signaling in Colorectal Cancer.

BACKGROUND & AIMS: N6-methyladenosine (m6A) governs the fate of RNAs through m6A readers. Colorectal cancer (CRC) exhibits aberrant m6A modifications and expression of m6A regulators. However, how m6A readers interpret oncogenic m6A methylome to promote malignant transformation remains to be illustrated. METHODS: YTH N6-methyladenosine RNA binding protein 1 (Ythdf1) knockout mouse was generated to determine the effect of Ythdf1 in CRC tumorigenesis in vivo. Multiomic analysis of RNA-sequencing, m6A methylated RNA immunoprecipitation sequencing, YTHDF1 RNA immunoprecipitation sequencing, and proteomics were performed to unravel targets of YTHDF1 in CRC. The therapeutic potential of targeting YTHDF1-m6A-Rho/Rac guanine nucleotide exchange factor 2 (ARHGEF2) was evaluated using small interfering RNA (siRNA) encapsulated by lipid nanoparticles (LNP). RESULTS: DNA copy number gain of YTHDF1 is a frequent event in CRC and contributes to its overexpression. High expression of YTHDF1 is significantly associated with metastatic gene signature in patient tumors. Ythdf1 knockout in mice dampened tumor growth in an inflammatory CRC model. YTHDF1 promotes cell growth in CRC cell lines and primary organoids and lung and liver metastasis in vivo. Integrative multiomics analysis identified RhoA activator ARHGEF2 as a key downstream target of YTHDF1. YTHDF1 binds to m6A sites of ARHGEF2 messenger RNA, resulting in enhanced translation of ARHGEF2. Ectopic expression of ARHGEF2 restored impaired RhoA signaling, cell growth, and metastatic ability both in vitro and in vivo caused by YTHDF1 loss, verifying that ARHGEF2 is a key target of YTHDF1. Finally, ARHGEF2 siRNA delivered by LNP significantly suppressed tumor growth and metastasis in vivo. CONCLUSIONS: We identify a novel oncogenic epitranscriptome axis of YTHDF1-m6A-ARHGEF2, which regulates CRC tumorigenesis and metastasis. siRNA-delivering LNP drug validated the therapeutic potential of targeting this axis in CRC.

Physical reserve: construct development and predictive utility.

BACKGROUND: Physical reserve (PR) refers to one's ability to maintain physical functioning despite age, illness, or injury. The measurement and predictive utility of PR, however, are not well established. AIMS: We quantified PR using a residual measurement approach by extracting standardized residuals from gait speed, while accounting for demographic and clinical/disease variables, and used it to predict fall-risk. METHODS: Participants (n = 510; age ≥ 70ys) were enrolled in a longitudinal study. Falls were assessed annually (in-person) and bimonthly (via structured telephone interview). RESULTS: General Estimating Equations (GEE) revealed that higher baseline PR was associated with reduced odds of reporting falls over repeated assessments in the total sample, and incident falls among those without fall's history. The protective effect of PR against fall risk remained significant when adjusting for multiple demographic and medical confounders. DISCUSSION/CONCLUSION: We propose a novel framework to assessing PR and demonstrate that higher PR is protective against fall-risk in older adults.

Hope and healthy lifestyle behaviors in older adulthood.

OBJECTIVES: Hope has been associated with better health and social well-being outcomes, including emotional adjustment, positive affect, life satisfaction, reduced risk of all-cause mortality, and increased physical activity, yet how hope as a construct impacts these health benefits in older adults is not very well-understood. This study examined: (1) the relationship between hope and health behaviors in older adults; (2) how this relationship may differ across different socio-demographic groups; and (3) how hope relates to perceived future selves among older adults. METHODS: The study used cross-sectional data from 711 community-dwelling adults aged ≥55 years (280 men, 431 women). Survey measures included the Snyder Adult Dispositional Hope Scale (ADHS) and the Herth Hope Index (HHI), a health behaviors checklist, self-reported health, and a future self-scale. Data were analyzed using bivariate and multiple regressions. RESULTS: Hope was positively associated with healthy behaviors in older adults. Participants with higher levels of hope also reported more positive future selves and better health. The associations were similar across different racial/ethnic groups. CONCLUSIONS: This study fills an important gap in our understanding of hope and its association with health behaviors in community-dwelling older adults. These findings highlight a need to promote hope in older adults in order to enhance their sense of well-being.

Controlling peripheral intravenous catheter failure by needleless connector design: A pilot randomised controlled trial.

AIM: To test the feasibility of a study protocol that compared the efficacy of neutral- and negative-pressure needleless connectors (NCs). DESIGN: A single-centre, parallel-group, pilot randomised control trial. METHODS: Our study compared neutral-(intervention) and negative-pressure (control) NCs among adult patients in an Australian hospital. The primary feasibility outcome was measured against predetermined criteria (e.g. eligibility, attrition). The primary efficacy outcome was all-cause peripheral intravenous catheter failure, analysed as time-to-event data. RESULTS: In total, 201 (100 control; 101 intervention) participants were enrolled between March 2020 and September 2020. All feasibility criteria were met except eligibility, which was lower (78%) than the 90% criterion. All-cause peripheral intravenous catheter failure was significantly higher in the intervention group (39%) compared to control (19%). CONCLUSION: With minor modifications to participant screening for eligibility, this randomised control trial is feasible for a large multicentre randomised control trial. The neutral NC was associated with an increased risk of peripheral intravenous catheter failure. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: There are several NC designs available, often identified by their mechanism of pressure (positive, negative and neutral). However, NCs can contribute to peripheral intravenous catheter failure. This is the first randomised controlled trial to compare neutral and negative NC designs. Negative pressure NCs had lower PIVC failure compared to neutral NCs, however the results might not be generalisable to other brands or treatment settings. Further high-quality research is needed to explore NC design. REPORTING METHOD: Study methods and results reported in adherence to the CONSORT Statement. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

Safety and efficacy of midline catheters versus peripheral intravenous catheters: A pilot randomized controlled trial.

BACKGROUND: Despite pervasive need for peripheral intravenous catheters, insertion is often difficult, and approximately two thirds fail prematurely. Midline catheters are an alternative long peripheral catheter, inserted in the upper arm, ideal for patients with difficult access. AIM: The aim of this study is to test feasibility of the protocol and compare the efficacy and safety of midline catheters to peripheral intravenous catheters. DESIGN: A parallel-group, pilot randomized controlled trial of adult medical/surgical hospitalized patients, from a single Australian referral hospital. METHODS: Participants with difficult vascular access (≤2 palpable veins) and/or anticipated ≥5 days of peripherally compatible intravenous therapy were recruited between May 2019 and March 2020. Participants were randomized to (1) peripheral intravenous catheter or (2) midline catheter. Primary feasibility outcome measured eligibility, recruitment, protocol adherence, retention and attrition. Primary clinical outcomes measured device insertion failure and post-insertion failure. RESULTS: In total, n = 143 participants (71 peripheral intravenous catheters and 72 midline catheters) were recruited; n = 139 were analysed. Most feasibility criteria were met. Peripheral intravenous catheters had shorter functional dwell time, with higher incidence of post-insertion failure compared to midline catheters. CONCLUSION: Midline catheters appear to be superior for patients with difficult vascular access or receiving prolonged intravenous therapy; a large, multi-centre trial to confirm findings is feasible.

Does longer peripheral intravenous catheter length optimise antimicrobial delivery? Protocol for the LEADER study.

BACKGROUND: Hospitalised patients receiving intravenous antimicrobial therapy require a reliable device through which this is delivered. Short peripheral intravenous catheters (PIVCs) are the default device for antimicrobial therapy but up to half fail before therapy completion, leading to suboptimal drug dosing, patient distress from repeated insertions, and increased healthcare costs. This study will investigate the use of long PIVCs to determine if they are more reliable at delivering antimicrobial therapy. METHODS: A two-arm, parallel randomised controlled trial of hospitalised adults requiring at least 3 days of peripherally compatible intravenous antimicrobials. Participants will be randomised to a short (<4 cm) or long (4.5-6.4 cm) PIVC. After interim analysis ( n=70) for feasibility and safety, 192 participants will be recruited. Primary outcome is disruption to antimicrobial administration from all-cause PIVC failure. Secondary outcomes include: number of devices to complete therapy, patient-reported pain and satisfaction, and a cost analysis. Ethical and regulatory approvals have been received.

Agreement of telemetric temperature capsules ingested 48 hours apart.

Telemetric temperature capsules are frequently utilized to measure deep body temperature. Whereas most methods to measure temperature are conducted at a single site (e.g., rectal temperature), the location of ingested telemetry capsules varies. If distinct regions of the gastrointestinal tract have different temperatures, the measurements obtained using telemetry capsules will vary accordingly. This study examined the agreement of two telemetric temperature capsules in fifty-seven Army Ranger School students ingested 64 and 16 h before a cool weather waterborne movement. Twenty-one subjects (37%) (age: 25 ± 4, weight: 81±7 kg) retained both capsules. Subjects completed activities that could increase (e.g. exercise) and decrease (e.g. cold water immersion) body temperature. Agreement between the two capsules was assessed through concordance and Bland Altman analysis using a linear mixed model. Bias between the two capsules was low (0.01 °C, SE = 0.03, before a neck-deep immersion river crossing and -0.09 °C, SE = 0.08, after the river crossing), but there were large differences in the variance components (0.044 vs 0.155 total variance for the pre-crossing vs the post-crossing data). The 95% Limits of Agreement indicate that discordance between the two capsules was lower before the river crossing (-0.40 to +0.42 °C) than after (-0.86 to +0.68 °C). In summary, this study examined telemetry capsule agreement with more time between capsule ingestion (48 h) in a larger sample size than most previous studies on the topic, and found notable (95% LoA>0.4 °C) variability between the two capsules which was exacerbated after crossing a cold river. Differences in gastrointestinal location of telemetry capsules can introduce variability into the measurement of deep body temperature due to regional temperature differences. This variability may be acceptable for some study designs, but unacceptable when small changes in temperature are important to detect. If the convenience of telemetric temperature capsules is desired, an alternative is to use the capsule as a rectal suppository.

Building research capacity and culture: Exploring nurses' experience of implementing a nurse-led clinical trial.

AIM: To explore the experiences of a nursing team who implemented an international nurse-led clinical trial in practice and understand the facilitators to their involvement. BACKGROUND: The role and responsibilities of the clinical nurse are advancing to encompass research activity to help inform evidence-based practice. However, several personal and organisational challenges can inhibit nurses' capacity to implement and undertake research within clinical practice. METHODS: Three focus groups were conducted with members of a nursing team (N = 18). Thematic analysis was employed, and themes were identified and agreed upon by the research team. RESULTS: Five themes were identified: 'Previous experience of and attitudes to participation in clinical research', 'Decision-making regarding participation in the clinical trial', 'Facilitators of participation in the clinical trial', 'Challenges of research in nursing practice' and 'Future orientation towards research'. CONCLUSION: Through their experiences of implementing a nurse-led clinical trial within practice, nurses recognized a number of facilitators and challenges to their participation. The perceived relevance of the clinical trial to the nurses' practice, potential to improve patient care and appreciation of the nurse leader's expertise and understanding of their context were key motivators. Reciprocal trust with the nurse leader who was encouraging, motivating, supportive and accessible resulted in the engagement and commitment of the nursing team. IMPLICATIONS FOR NURSING MANAGEMENT: This paper offers a perspective that can inform senior nursing management teams when implementing and conducting evidence-based research amongst nursing teams and in doing so meet the needs of developing research capacity amongst clinical nurses.

Adequacy of lymph node harvest following colectomy for obstructed and nonobstructed colon cancer.

BACKGROUND: Technical and clinical differences in resection of obstructed and non-obstructed colon cancers may result in differences in lymph node retrieval. The objective of this study is to compare the lymph node harvest following resection of obstructed and nonobstructed colon cancer patients. METHODS: A retrospective analysis utilizing the 2014-2018 NSQIP colectomy targeted data set was conducted. One-to-one coarsened exact matching (CEM) was utilized between patients undergoing resection for obstructed and non-obstructed colon cancer. The primary outcome was the adequacy of lymph node retrieval (LNR, ≥12 nodes). RESULTS: CEM resulted in 9412 patients. Patients with obstructed tumors were more likely to have inadequate LNR (13.3% vs 8.2%, p < .001) compared to those with nonobstructed tumors. Multivariate analysis demonstrated that patients with obstructing tumors had worse LNR compared to non-obstructed tumors (odds ratio [OR]: 0.74, 95% confidence interval [CI]: 0.62-0.87; p < .005). Increased age (OR: 0.99, 95% CI: 0.098-0.99), presence of preoperative sepsis (OR: 0.70, 95% CI: 0.055-0.90), left-sided and sigmoid tumors compared to right-sided (OR: 0.64, 95% CI: 0.51-0.81; OR: 0.69, 95% CI: 0.58-0.82, respectively), and open surgical resection compared to an minimally invasive surgical approach were associated with inadequate LNR (p < .05). CONCLUSION: This study demonstrated that resection for obstructing colon cancer compared to non-obstructed colon cancer is associated with increased odds of inadequate lymph node harvest.

Inherent and modifiable risk factors for peripheral venous catheter failure during cancer treatment: a prospective cohort study.

PURPOSE: To identify modifiable and non-modifiable risk factors for peripheral intravenous catheter (PIV) failure among patients requiring intravenous treatment for oncology and haematology conditions. METHODS: A single-centre prospective cohort study was conducted between October 2017 and February 2019. Adult in-patients requiring a PIV for therapy were prospectively recruited from two cancer units at a tertiary hospital in Queensland, Australia. The primary outcome was a composite of complications leading to PIV failure (local and bloodstream infection; occlusion; infiltration/extravasation; leakage; dislodgement; and/or phlebitis). Secondary outcomes were (i) PIV dwell time; (ii) insertion and (iii) failure of a CVAD; (iv) adverse events; (v) length of hospital stay. Outcomes were investigated using Bayesian multivariable linear regression modelling and survival analysis. RESULTS: Of 200 participants, 396 PIVs were included. PIV failure incidence was 34.9%; the most common failure type was occlusion/infiltration (n = 74, 18.7%), then dislodgement (n = 33, 8.3%), and phlebitis (n = 30, 7.6%). While several patient and treatment risk factors were significant in univariable modelling, in the final multivariable model, only the use of non-sterile tape (external to the primary dressing) was significantly associated with decreased PIV dislodgement (hazard ratio 0.06, 95% confidence interval 0.01, 0.48; p = 0.008). CONCLUSION: PIV failure rates among patients receiving cancer treatment are high, the sequelae of which may include delayed treatment and infection. Larger studies on risk factors and interventions to prevent PIV failure in this population are needed; however, the use of secondary securements (such as non-sterile tape) to provide further securement to the primary PIV dressing is particularly important. TRIAL REGISTRATION: Study methods were registered prospectively with the Australian New Zealand Clinical Trials Registry on the 27th March 2017 (ACTRN12617000438358); https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372191&isReview=true.

Associations Between Religious/Spiritual Coping and Depression Among Adults with Cystic Fibrosis: A 12-Month Longitudinal Study.

Individuals with cystic fibrosis (CF) face a challenging disease, and depression is a significant concern. Many patients draw on religious/spiritual resources to assist them in managing the demands of chronic illness; however, these coping efforts rarely have been evaluated among adults with CF. This longitudinal study examined relationships between distinct types of positive and negative religious/spiritual coping at baseline (assessed with the RCOPE) and depression screening outcomes 12 month later (assessed with the Hospital Anxiety and Depression Scale). In logistic regression analyses controlling for disease severity (FEV1% predicted), lower likelihood of depression caseness at 12 months was predicted by higher general religiousness at baseline, greater use of benevolent religious reappraisal coping, greater use of spiritual connection coping, and lower spiritual discontent. Results suggest that distinct aspects religious/spiritual coping have differential associations with subsequent depression outcomes. Findings extend prior research to an important, understudied medical population, and address a clinically meaningful outcome.