Circadian Timing in Cancer Treatments

Microbiota and metabolites alterations in proximal and distal gastric cancer patients

Background

Globally, gastric cancer is the third most common cancer and the third leading cause of cancer death. Proximal and distal gastric cancers have distinct clinical and biological behaviors. The microbial composition and metabolic differences in proximal and distal gastric cancers have not been fully studied and discussed.

Methods

In this study, the gastric microbiome of 13 proximal gastric cancer tissues, 16 distal gastric cancer tissues, and their matched non-tumor tissues were characterized using 16S rRNA amplicon sequencing. Additionally, 10 proximal gastric cancer tissues, 11 distal gastric cancer tissues, and their matched non-tumor tissues were assessed by untargeted metabolomics.

Results

There was no significant difference in microbial diversity and richness between the proximal and distal gastric cancer tissues. At the genus level, the abundance of Rikenellaceae_RC9_gut_group, Porphyromonas, Catonella, Proteus, Oribacterium, and Moraxella were significantly increased in Proximal T, whereas that of Methylobacterium_Methylorubrum was significantly increased in Distal T. The untargeted metabolomics analysis revealed 30 discriminative metabolites between Distal T and Distal N. In contrast, there were only 4 discriminative metabolites between Proximal T and Proximal N. In distal gastric cancer, different metabolites were scattered through multiple pathway, including the sphingolipid signaling pathway, arginine biosynthesis, protein digestion and absorption, alanine, aspartate and, glutamate metabolism, etc.In proximal gastric cancer, differential microbial metabolites were mainly related to hormone metabolism.

Conclusion

Methylobacterium-Methylorubrum was significantly increased in Distal T, positively correlated with cancer-promoting metabolites, and negatively correlated with cancer-inhibiting metabolites. Rikenellaceae_RC_gut_group was significantly increased in Proximal T and positively correlated with cancer-promoting metabolites. Further studies regarding the functions of the above-mentioned microorganisms and metabolites were warranted as the results may reveal the different mechanisms underlying the occurrence and development of proximal and distal gastric cancers and provide a basis for future treatments.

Importance

First, the differences in microbial composition and metabolites between the proximal and distal gastric cancers were described; then, the correlation between microbiota and metabolites was preliminarily discussed. These microbes and metabolites deserve further investigations as they may reveal the different mechanisms involved in the occurrence and development of proximal and distal gastric cancers and provide a basis for future treatments.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03650-x.

A guideline proposal for mice preparation and care in 18F-FDG PET imaging

The experimental outcomes of small-animal positron emission tomography (PET) imaging with ¹⁸F-labelled fluorodeoxyglucose (¹⁸F-FDG) can be particularly compromised by animal preparation and care. Several works intend to improve research reporting and amplify the quality and reliability of published research. Though these works provide valuable information to plan and conduct animal studies, manuscripts describe different methodologies—standardization does not exist. Consequently, the variation in details reported can explain the difference in the experimental results found in the literature. Additionally, the resources and guidelines defining protocols for small-animal imaging are scarce, making it difficult for researchers to obtain and compare accurate and reproducible data. Considering the selection of suitable procedures key to ensure animal welfare and research improvement, this paper aims to prepare the way for a future guideline on mice preparation and care for PET imaging with ¹⁸F-FDG. For this purpose, a global standard protocol was created based on recommendations and good practices described in relevant literature.

Récepteurs nucléaires et rythmes circadiens

L’horloge circadienne programme l’ensemble des processus physiologiques, dont l’activité du système immunitaire, à des moments précis de la journée. Elle permet d’optimiser les fonctions de l’organisme en anticipant les changements quotidiens tels que les cycles jour/nuit. Nos habitudes de vie comme l’exposition à la lumière artificielle ou une prise alimentaire irrégulière désynchronisent cependant cette horloge et provoquent des maladies, par exemple inflammatoires. Au niveau moléculaire, elle consiste en un réseau de facteurs de transcription dont certains sont des récepteurs nucléaires, activables par des ligands. Une meilleure compréhension des rythmes biologiques et du rôle des récepteurs nucléaires de l’horloge circadienne permettrait d’ouvrir un champ thérapeutique nouveau. La chronothérapie qui consiste en l’administration d’un composé pharmacologique au moment de la journée le plus propice, permettrait, en ciblant ces récepteurs, d’optimiser l’efficacité du traitement et d’en réduire les possibles effets secondaires.

Genome-wide CRISPR Screening Reveals Pyrimidine Metabolic Reprogramming in 5-FU Chronochemotherapy of Colorectal Cancer

Objective

Disruption of the circadian rhythm is associated with cancer occurrence, response to chemotherapy, and poor prognosis. Thus, using internal clock-based chronotherapy to optimize the administration time may improve the therapeutic effects of anticancer drugs while reducing the side effects. Chronotherapy with 5-fluorouracil (5-FU) has been observed in colorectal cancer (CRC) for a long time, but its effect is under controversial and the mechanism remains unclear.

Methods

Genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screening and RNA-sequencing were combined to identify the potential genes or pathways involved in 5-FU chronochemotherapy. Genetic deletion or overexpression of pyrimidine metabolic pathway genes were conducted to examine cellular viability with or without 5-FU via flow cytometry. Western blotting, qPCR, chromatin immunoprecipitation, gain-of-function and loss-of-function assays of several CRC cell lines in vitro and in vivo were used to elaborate and validate the mechanism of 5-FU chronotherapeutic effects.

Results

Chronochemotherapeutic effects of 5-FU on CRC in vivo were verified. Furthermore, 5-FU chronochemotherapy related genes such as UPP2, UCK2 and UMPS in the pyrimidine metabolic pathway were identified. Disturbance in these genes, especially UMPS, perturbs 5-FU treatment outcomes in CRC cells. Mechanistically, the core circadian gene, brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein-1 (BMAL1), extensively regulate gene expression in pyrimidine metabolic pathway by binding to E-box element in the promoter region of key genes such as UMPS and perturb their enzymatic activities, thereby maintain diurnal efficacy of 5-FU in CRC cells.

Conclusion

This study uncovered a new mechanism by which a core circadian gene BMAL1 increases the effectiveness of 5-FU by enhancing the expression and enzymatic activities of key genes in the pyrimidine metabolic pathway in CRC cells. The findings suggest a novel strategy for CRC chemotherapy by targeting chrono-modulated genes of the 5-FU metabolic pathway.

Effects and Prognostic Values of Circadian Genes CSNK1E/GNA11/KLF9/THRAP3 in Kidney Renal Clear Cell Carcinoma via a Comprehensive Analysis

Kidney renal clear cell carcinoma (KIRC) is one of the most prevalent and deadly types of renal cancer in adults. Recent research has identified circadian genes as being involved in the development and progression of KIRC by altering their expression. This study aimed to identify circadian genes that are differentially expressed in KIRC and assess their role in KIRC progression. In KIRC, there were 553 differentially expressed rhythm genes (DERGs), with 300 up-regulated and 253 down-regulated DERGs. Functional enrichment analyses showed that DERGs were greatly enriched in the circadian rhythm and immune response pathways. Survival analyses indicated that higher expression levels of CSNK1E were related to shorter overall survival of KIRC patients, whereas lower expression levels of GNA11, KLF9, and THRAP3 were associated with shorter overall survival of KIRC patients. Through cell assay verification, the mRNA level of CSNK1E was significantly up-regulated, whereas the mRNA levels of GNA11, KLF9, and THRAP3 were dramatically down-regulated in KIRC cells, which were consistent with the bioinformatics analysis of KIRC patient samples. Age, grade, stage, TM classification, and CSNK1E expression were all shown to be high-risk variables, whereas GNA11, KLF9, and THRAP3 expression were found to be low-risk factors in univariate Cox analyses. Multivariate Cox analyses showed that CSNK1E and KLF9 were also independently related to overall survival. Immune infiltration analysis indicated that the proportion of immune cells varied greatly between KIRC tissues and normal tissue, whereas CSNK1E, GNA11, KLF9, and THRAP3 expression levels were substantially linked with the infiltration abundance of immune cells and immunological biomarkers. Moreover, interaction networks between CSNK1E/GNA11/KLF9/THRAP3 and immune genes were constructed to explore the stream connections. The findings could help us better understand the molecular mechanisms of KIRC progression, and CSNK1E/GNA11/KLF9/THRAP3 might be used as molecular targets for chronotherapy in KIRC patients in the near future.

The 4th dimension of in vitro systems - Time to level up

Various in vitro model systems have been established over the last decades to understand physiological processes, the causalities of diseases and the response of humans to environmental and industrial chemicals or therapeutic drugs. Common to all is a limited biological significance due to the impairment of functionality, for instance by the lack of physiological 3D tissue architecture or the loss of fundamental regulatory mechanisms including the circadian rhythm. The circadian rhythm is an adaption of living organisms to rhythmic environmental changes of the day-night cycle and coordinates behavior as well as various crucial physiological processes in a 24-hour pattern. Here, we discuss the impact of integrating circadian regulation in experimental approaches and toxicological assessments to improve the biological relevance of the obtained results. In particular, it is known for some time that an ongoing disruption of the circadian rhythmicity is associated with an increased risk for cardiovascular disease, metabolic dysfunction or cancer. In the context of health recovery, the importance of circadian control mechanism is recognized by chronopharmacological concepts to increase the efficiency of pharmacological treatment strategies. Despite the undeniable circadian dependency and the biological relevance of manifold cellular and molecular processes, the impact of circadian regulation is hardly considered in a wide range of biomedical and toxicological research areas. Reactivating the circadian regulation holds the promise to enhance the biological relevance and reliability of in vitro approaches. In the context of human health protection the implementation of a circadian regulation will subsequently generate advanced physiologically relevant in vitro approaches and allows an improved toxicological assessment of health risks. In addition, the establishment of circadian disruption as a novel toxicological endpoint will provide a better understanding of toxicological mode of actions of environmental and industrial chemicals or drugs and enlarge the knowledge of disease development.

Transcriptome analysis of clock disrupted cancer cells reveals differential alternative splicing of cancer hallmarks genes

Emerging evidence points towards a regulatory role of the circadian clock in alternative splicing (AS). Whether alterations in core-clock components may contribute to differential AS events is largely unknown. To address this, we carried out a computational analysis on recently generated time-series RNA-seq datasets from three core-clock knockout (KO) genes (ARNTL, NR1D1, PER2) and WT of a colorectal cancer (CRC) cell line, and time-series RNA-seq datasets for additional CRC and Hodgkin’s lymphoma (HL) cells, murine WT, Arntl KO, and Nr1d1/2 KO, and murine SCN WT tissue. The deletion of individual core-clock genes resulted in the loss of circadian expression in crucial spliceosome components such as SF3A1 (in ARNTL^KO), SNW1 (in NR1D1^KO), and HNRNPC (in PER2^KO), which led to a differential pattern of KO-specific AS events. All HCT116^KO cells showed a rhythmicity loss of a crucial spliceosome gene U2AF1, which was also not rhythmic in higher progression stage CRC and HL cancer cells. AS analysis revealed an increase in alternative first exon events specific to PER2 and NR1D1 KO in HCT116 cells, and a KO-specific change in expression and rhythmicity pattern of AS transcripts related to cancer hallmarks genes including FGFR2 in HCT116_ARNTL^KO, CD44 in HCT116_NR1D1^KO, and MET in HCT116_PER2^KO. KO-specific changes in rhythmic properties of known spliced variants of these genes (e.g. FGFR2 IIIb/FGFR2 IIIc) correlated with epithelial-mesenchymal-transition signalling. Altogether, our bioinformatic analysis highlights a role for the circadian clock in the regulation of AS, and reveals a potential impact of clock disruption in aberrant splicing in cancer hallmark genes.

FBXW7 and the Hallmarks of Cancer: Underlying Mechanisms and Prospective Strategies

FBXW7, a member of the F-box protein family within the ubiquitin–proteasome system, performs an indispensable role in orchestrating cellular processes through ubiquitination and degradation of its substrates, such as c-MYC, mTOR, MCL-1, Notch, and cyclin E. Mainly functioning as a tumor suppressor, inactivation of FBXW7 induces the aberrations of its downstream pathway, resulting in the occurrence of diseases especially tumorigenesis. Here, we decipher the relationship between FBXW7 and the hallmarks of cancer and discuss the underlying mechanisms. Considering the interplay of cancer hallmarks, we propose several prospective strategies for circumventing the deficits of therapeutic resistance and complete cure of cancer patients.

Circadian rhythms and cancers: the intrinsic links and therapeutic potentials

The circadian rhythm is an evolutionarily conserved time-keeping system that comprises a wide variety of processes including sleep-wake cycles, eating-fasting cycles, and activity-rest cycles, coordinating the behavior and physiology of all organs for whole-body homeostasis. Acute disruption of circadian rhythm may lead to transient discomfort, whereas long-term irregular circadian rhythm will result in the dysfunction of the organism, therefore increasing the risks of numerous diseases especially cancers. Indeed, both epidemiological and experimental evidence has demonstrated the intrinsic link between dysregulated circadian rhythm and cancer. Accordingly, a rapidly increasing understanding of the molecular mechanisms of circadian rhythms is opening new options for cancer therapy, possibly by modulating the circadian clock. In this review, we first describe the general regulators of circadian rhythms and their functions on cancer. In addition, we provide insights into the mechanisms underlying how several types of disruption of the circadian rhythm (including sleep-wake, eating-fasting, and activity-rest) can drive cancer progression, which may expand our understanding of cancer development from the clock perspective. Moreover, we also summarize the potential applications of modulating circadian rhythms for cancer treatment, which may provide an optional therapeutic strategy for cancer patients.

Understanding the significance of biological clock and its impact on cancer incidence

The circadian clock is an essential timekeeper that controls, for humans, the daily rhythm of biochemical, physiological, and behavioral functions. Irregular performance or disruption in circadian rhythms results in various diseases, including cancer. As a factor in cancer development, perturbations in circadian rhythms can affect circadian homeostasis in energy balance, lead to alterations in the cell cycle, and cause dysregulation of chromatin remodeling. However, knowledge gaps remain in our understanding of the relationship between the circadian clock and cancer. Therefore, a mechanistic understanding by which circadian disruption enhances cancer risk is needed. This review article outlines the importance of the circadian clock in tumorigenesis and summarizes underlying mechanisms in the clock and its carcinogenic mechanisms, highlighting advances in chronotherapy for cancer treatment.

Science Forum: Sex differences and sex bias in human circadian and sleep physiology research

Growing evidence shows that sex differences impact many facets of human biology. Here we review and discuss the impact of sex on human circadian and sleep physiology, and we uncover a data gap in the field investigating the non-visual effects of light in humans. A virtual workshop on the biomedical implications of sex differences in sleep and circadian physiology then led to the following imperatives for future research: (1) design research to be inclusive and accessible, (2) implement recruitment strategies that lead to a sex-balanced sample, (3) use data visualization to grasp the effect of sex, (4) implement statistical analyses that include sex as a factor and/or perform group analyses by sex, where possible, (5) make participant-level data open and available to facilitate future meta-analytic efforts.

Chronotherapy of Early Colon Cancer: Advantage of Morning Dose Schedules

Colon adenomas with proliferating mutant cells may progress to invasive carcinomas. Proliferation of cells in human colorectal tissue is circadian, greater in the interval 4 to 12 hours after midnight than 16 to 24 hours after midnight. We have tested the hypothesis that chemotherapy administered during the time of greater cell proliferation will be more effective than chemotherapy administered during the time of lesser proliferation. An agent-based computer model of cell proliferation in colon crypts was calibrated with measurements of cell numbers in human biopsy specimens. It was used to simulate cytotoxic chemotherapy of an early stage of colon cancer, adenomas with about 20% of mutant cells. Chemotherapy doses were scheduled at different 4-hour intervals during the 24-hour day, and repeated at weekly intervals. Chemotherapy administered at 4 to 8 hours after midnight cured mutant cells in 100% of 50 trials with an average time to cure of 7.82 days (s.e.m. = 0.99). In contrast, chemotherapy administered at 20 to 24 hours after midnight cured only 18% of 50 trials, with the average time to cure of 23.51 days (s.e.m. = 2.42). These simulation results suggest that clinical chemotherapy of early colon cancer may be more effective when given in the morning than later in the day.

Chronodisruption and Ambulatory Circadian Monitoring in Cancer Patients: Beyond the Body Clock

Purpose of Review

Circadian rhythms impose daily rhythms a remarkable variety of metabolic and physiological functions, such as cell proliferation, inflammation, and DNA damage response. Accumulating epidemiological and genetic evidence indicates that circadian rhythms’ disruption may be linked to cancer. The integration of circadian biology into cancer research may offer new options for increasing cancer treatment effectiveness and would encompass the prevention, diagnosis, and treatment of this disease.

Recent Findings

In recent years, there has been a significant development and use of multi-modal sensors to monitor physical activity, sleep, and circadian rhythms, allowing, for the very first time, scaling accurate sleep monitoring to epidemiological research linking sleep patterns to disease, and wellness applications providing new potential applications.

Summary

This review highlights the role of circadian clock in tumorigenesis, cancer hallmarks and introduces the state-of-the-art in sleep-monitoring technologies, discussing the eventual application of insights in clinical settings and cancer research.

New Insights Into Cancer Chronotherapies

Circadian clocks participate in the coordination of various metabolic and biological activities to maintain homeostasis. Disturbances in the circadian rhythm and cancers are closely related. Circadian clock genes are differentially expressed in many tumors, and accelerate the development and progression of tumors. In addition, tumor tissues exert varying biological activities compared to normal tissues due to resetting of altered rhythms. Thus, chronotherapeutics used for cancer treatment should exploit the timing of circadian rhythms to achieve higher efficacy and mild toxicity. Due to interpatient differences in circadian functions, our findings advocate an individualized precision approach to chronotherapy. Herein, we review the specific association between circadian clocks and cancers. In addition, we focus on chronotherapies in cancers and personalized biomarkers for the development of precision chronotherapy. The understanding of circadian clocks in cancer will provide a rationale for more effective clinical treatment of tumors.

A multidisciplinary perspective on the complex interactions between sleep, circadian, and metabolic disruption in cancer patients

Sleep is a basic need that is frequently set aside in modern societies. This leads to profound but complex physiological maladaptations in the body commonly referred to as circadian disruption, which recently has been characterized as a carcinogenic factor and reason for poor treatment outcomes, shortened survival, and reduced quality of life in cancer patients. As sleep and circadian physiology in cancer patients spans several disciplines including nursing science, neurology, oncology, molecular biology and medical technology, there is a lack of comprehensive and integrated approaches to deal with this serious and growing issue and at best a fractionated understanding of only part of the problem among researchers within each of these segments. Here, we take a multidisciplinary approach to comprehensively review the diagnosis and impact of sleep and circadian disruption in cancer patients. We discuss recent discoveries on molecular regulation of the circadian clock in healthy and malignant cells, the neurological and endocrine pathways controlling sleep and circadian rhythmicity, and their inputs to and outputs from the organism. The benefits and drawbacks of the various technologies, devices, and instruments used to assess sleep and circadian function, as well as the known consequences of sleep disruption and how sleep can be corrected in cancer patients, will be analyzed. We will throughout the review highlight the extensive crosstalk between sleep, circadian rhythms, and metabolic pathways involved in malignancy and identify current knowledge gaps and barriers for addressing the issue of sleep and circadian disruption in cancer patients. By addressing these issues, we hope to provide a foundation for further research as well as better and more effective care for the patients in the future.

Circadian and chemotherapy-related changes in urinary modified nucleosides excretion in patients with metastatic colorectal cancer

Urinary levels of modified nucleosides reflect nucleic acids turnover and can serve as non-invasive biomarkers for monitoring tumour circadian dynamics, and treatment responses in patients with metastatic colorectal cancer. In 39 patients, median overnight urinary excretion of LC-HRMS determinations of pseudouridine, was ~ tenfold as large as those of 1-methylguanosine, 1-methyladenosine, or 4-acetylcytidine, and ~ 100-fold as large as those of adenosine and cytidine. An increase in any nucleoside excretion after chemotherapy anticipated plasma carcinoembryonic antigen progression 1–2 months later and was associated with poor survival. Ten fractionated urines were collected over 2-days in 29 patients. The median value of the rhythm-adjusted mean of urinary nucleoside excretion varied from 64.3 for pseudouridine down to 0.61 for cytidine. The rhythm amplitudes relative to the 24-h mean of 6 nucleoside excretions were associated with rest duration, supporting a tight link between nucleosides turnover and the rest-activity rhythm. Moreover, the amplitude of the 1-methylguanosine rhythm was correlated with the rest-activity dichotomy index, a significant predictor of survival outcome in prior studies. In conclusion, urinary excretion dynamics of modified nucleosides appeared useful for the characterization of the circadian control of cellular proliferation and for tracking early responses to treatments in colorectal cancer patients.

A mathematical model of the circadian clock and drug pharmacology to optimize irinotecan administration timing in colorectal cancer

Scheduling anticancer drug administration over 24 h may critically impact treatment success in a patient-specific manner. Here, we address personalization of treatment timing using a novel mathematical model of irinotecan cellular pharmacokinetics and -dynamics linked to a representation of the core clock and predict treatment toxicity in a colorectal cancer (CRC) cellular model. The mathematical model is fitted to three different scenarios: mouse liver, where the drug metabolism mainly occurs, and two human colorectal cancer cell lines representing an in vitro experimental system for human colorectal cancer progression. Our model successfully recapitulates quantitative circadian datasets of mRNA and protein expression together with timing-dependent irinotecan cytotoxicity data. The model also discriminates time-dependent toxicity between the different cells, suggesting that treatment can be optimized according to their cellular clock. Our results show that the time-dependent degradation of the protein mediating irinotecan activation, as well as an oscillation in the death rate may play an important role in the circadian variations of drug toxicity. In the future, this model can be used to support personalized treatment scheduling by predicting optimal drug timing based on the patient's gene expression profile.

NPAS2 ameliorates myocardial ischaemia/reperfusion injury in rats via CX3CL1 pathways and regulating autophagy

BACKGROUND

Myocardial ischemia/reperfusion (I/R) injury is common during the treatment of cardiovascular diseases. Neuronal PAS Domain Protein 2 (NPAS2) is one of the core genes that control the rhythm of the biological clock. NPAS2 also regulates the biological rhythm.

RESULTS

The rat I/R model showed that the expression of NPAS2 decreased with the increase of reperfusion time. Overexpressing NPAS2 adenovirus (ad-NPAS2) was injected into IR rat which demonstrated that ad-NPAS2 ameliorated rats I/R injury. A hypoxia/reoxygenation (H/R) model in rat cardiomyocytes showed that ad-NPAS2 inhibited cardiomyocyte apoptosis. Co-Immunoprecipitation results showed that there is an interaction between NPAS2 and Cry2. Knockdown of Cry2 aggravated the cardiomyocyte apoptosis induced by H/R. Additionally, NPAS2 directly act on the promoter region of CX3CL1. Knockdown of CX3CL1 reverse the protective effect of ad-NPAS2 on rat myocardial ischemia-reperfusion injury and H/R-induced cardiomyocyte apoptosis. CX3CL1 also regulates autophagy through the downstream AKT/mTOR pathway.

CONCLUSIONS

research demonstrated that overexpression of NPAS2 interacts with Cry2 and promotes the transcriptional activity of CX3CL1. Moreover, overexpression of NPAS2 regulates the downstream AKT/mTOR pathway to inhibit autophagy in order to improve rat cardiac I/R injury.

Relationship of Circadian Rhythm and Psychological Health in Adolescents and Young Adults With Cancer

BACKGROUND

Evidence shows that adolescent and young adult (AYA) cancer patients have an increasing survival rate but experience psychological distress and circadian rhythm dysregulation. Little is known about the effect of circadian rhythm on psychological distress.

OBJECTIVE

To investigate the type of circadian rhythm in Chinese AYA cancer survivors and examine the associations among chronotype, demographic characteristics, psychological distress, anxiety and depression, character strengths, and medical coping in this group.

METHODS

This cross-sectional study enrolled 800 AYA cancer participants, 728 of whom completed the Chinese version of the Morningness-Eveningness Questionnaire, the Distress Thermometer, the Hospital Anxiety and Depression Scale, the Three-Dimensional Inventory of Character Strengths, and the Medical Coping Modes Questionnaire.

RESULTS

Evening- and morning-type participants accounted for 35.0% and 19.1%, respectively, among participants, which was significantly higher than those found in the general population. The prevalence of psychological distress was 84.9% among AYA cancer participants. Exercise, Distress Thermometer, and depression were important predictive factors for the circadian rhythm.

CONCLUSIONS

Circadian rhythm disorder and psychological distress were common among AYA cancer survivors. Evening-type participants performed worse on character strength, confrontation, and avoidance of medical coping.

IMPLICATIONS FOR PRACTICE

Healthcare professionals need to understand the circadian rhythm and psychological health of AYA cancer survivors. Psychological rehabilitation guidance, especially within the 6 months after diagnosis, may benefit AYA survivors according to their chronotype. Character strengths can also be used during rehabilitation to properly guide AYA survivors.

Circadian disruption in lung cancer

Despite major developments in lung cancer investigations and the progress of innovative oncology treatments in recent decades, lung cancer continues to be the predominant cause of cancer-related mortality globally, with over a million deaths each year. This highlights the urgent need to develop a deeper understanding of the current state of cancer care. At the environmental and cellular levels, circadian rhythms are closely associated with living organisms. In humans, the suprachiasmatic nucleus is the principal circadian pacemaker. Circadian gene feedback loops regulate the clock, connecting peripheral tissue metabolism, cell proliferation, DNA repair, and cell death to energy homeostasis, physical activity, and neurohormonal regulation at the organismal level. Endogenous circadian homeostasis has been frequently disturbed in modern civilizations, resulting in a higher risk of many disorders, including lung cancer. Despite major developments in lung cancer investigations and the progress of innovative oncology treatments in recent decades, lung cancer continues to be the predominant cause of cancer-related mortality globally, with over a million deaths each year. This highlights the urgent need to develop a deeper understanding of the current state of cancer care. At the environmental and cellular levels, circadian rhythms are closely associated with living organisms. In humans, the suprachiasmatic nucleus is the principal circadian pacemaker. Circadian gene feedback loops regulate the clock, connecting peripheral tissue metabolism, cell proliferation, DNA repair, and cell death to energy homeostasis, physical activity, and neurohormonal regulation at the organismal level. Endogenous circadian homeostasis has been frequently disturbed in modern civilizations, resulting in a higher risk of many disorders, including lung cancer. The mammalian circadian clock controls metabolism and cell division, and disruption of these processes may lead to cancer pathogenesis. Furthermore, circadian disturbance has recently been identified as a self-regulating cancer risk factor and is listed as a carcinogen. The theory that both somatic and systemic disturbances of circadian rhythms are related to a higher risk of lung cancer development and poor prognosis is addressed in this study. The chronotherapy principles hold much more promise for enhancing the lung cancer care options currently available. Developing a better understanding of the molecular interactions that control the physiological equilibrium between both the circadian rhythm and the cycle of cell division could significantly influence the development of novel treatments for lung cancer and other diseases.

Dosing-time dependent testicular toxicity of everolimus in mice

The circadian timing system controls many biological functions in mammals including drug metabolism and detoxification, cell cycle events, and thus may affect pharmacokinetics, target organ toxicity and efficacy of medicines. Selective mTOR (mammalian target of rapamycin) inhibitor everolimus is an immunosuppressant and anticancer drug that is effective against several cancers. The aim of this study was to investigate dosing-time dependent testicular toxicity of subacute everolimus administration in mice. C57BL/6 J male mice were synchronized with Light-Dark (12h:12 h) cycle, with Light-onset at Zeitgeber Time (ZT)-0. Everolimus (5 mg/kg/day) was administered orally to mice at ZT1_rest-span or ZT13_{activity-span} for 4 weeks. Body weight loss, clinical signs, changes in testicular weights, testis histology, spermatogenesis and proliferative activity of germinal epithelium of seminiferous tubules were examined. Steady-state everolimus concentrations in testes were determined with validated HPLC method. Everolimus toxicity was less severe following dosing at ZT13 compared to ZT1, as shown with least body weight loss (p<0.001), least reductions in testes weights (p<0.001) and least histopathological findings. Everolimus-induced histological changes on testes included vacuolisation and atrophy of germinal epithelium, and loss of germinal cell attachment. The severity of everolimus-induced histological toxicity on testes was significantly more evident in mice treated at ZT1 than ZT13 (p<0.001). Spermatogenic cell population significantly decreased when everolimus administered at ZT1 compared to ZT13 (p<0.001). Proliferative activity of germinal epithelium was significantly decreased due to treatment at ZT1 compared to ZT13 (p<0.001). Everolimus concentrations in testes indicated a pronounced circadian variation, which was greater in mice treated at ZT1 compared to ZT13 (p<0.05). Our study revealed dosing-time dependent testicular toxicity of everolimus in mice, which was greater in severity when everolimus administered at early rest-span (daytime-ZT1) than early activity-span (nighttime-ZT13). These findings support the concept of everolimus chronotherapy for minimizing reproductive toxicity and increasing the tolerability of everolimus, as a clinical advantage.

Exploring the link between chronobiology and drug delivery: effects on cancer therapy

Circadian clock is an impressive timing system responsible for the control of several metabolic, physiological and behavioural processes. Nowadays, the connection between the circadian clock and cancer occurrence and development is consensual. Therefore, the inclusion of circadian timing into cancer therapy may potentially offer a more effective and less toxic approach. This way, chronotherapy has been shown to improve cancer treatment efficacy. Despite this relevant finding, its clinical application is poorly exploited. The conception of novel anticancer drug delivery systems and the combination of chronobiology with nanotechnology may provide a powerful tool to optimize cancer therapy, instigating the incorporation of the circadian timing into clinical practice towards a more personalized drug delivery. This review focuses on the recent advances in the field of cancer chronobiology, on the link between cancer and the disruption of circadian rhythms and on the promising targeted drug nanodelivery approaches aiming the clinical application of cancer chronotherapy.

Alterations of sleep quality and circadian rhythm genes expression in elderly thyroid nodule patients and risks associated with thyroid malignancy

To study the alterations of sleep quality and circadian rhythm genes expressions upon elderly thyroid nodule patients, the risk factors associated with thyroid malignancies, and the potential relationship involved. The elderly people enrolled in our study were divided into three groups according to the thyroid histopathology: malignant nodule group, benign nodule group, and normal group, and the clinical data and sleep quality were collected. Among the patients of surgery, 56 fresh thyroid tissues were collected for real-time PCR, immunohistochemistry and western blotting analysis of CLOCK, BMAL1, CRYs and PERs. Poor sleep quality, sleep latency and daytime dysfunction were the independent risk factors of malignant nodule after adjusted by other impacts. The expression levels of CLOCK, BMAL1 and PER2 in thyroid malignant group were significantly higher than benign and normal groups, while CRY2 was decreased, p < 0.05. In addition, CLOCK and BMAL1 protein levels were positively correlated with PSQI of corresponding patients and CRY2 was negatively correlated. Circadian rhythm genes mainly altered in malignant nodules, and sleep disorders may be involved in the occurrence of elderly thyroid malignancy through the high expressions of CLOCK and BMAL1, and low expression of CRY2.

His and her mathematical models of physiological systems

Beyond the reproductive system and reproductive behaviors, men and women exhibit major differences in many organ systems, including the anatomy of the brain, the activities of the stress and immune systems, and the metabolic and cardiovascular functions. A comprehensive understanding of the impact of these sex differences on health and disease is crucial to the development of effective sex-based therapies. Mathematical modeling has the potential of facilitating and contributing to advancing the understanding of sex differences in health and disease. Indeed, explosion of mathematical models have been developed in recent decades for different aspects of human physiology and pathophysiology. This review contains a survey of sex-specific mathematical models of physiological systems, describe insights that have been revealed in those modeling studies, and discuss future opportunities.

Bioinformatics Analysis of Differentially Expressed Rhythm Genes in Liver Hepatocellular Carcinoma

Liver Hepatocellular Carcinoma (LIHC), a malignant tumor with high incidence and mortality, is one of the most common cancers in the world. Multiple studies have found that the aberrant expression of rhythm genes is closely related to the occurrence of LIHC. This study aimed to use bioinformatics analysis to identify differentially expressed rhythm genes (DERGs) in LIHC. A total of 563 DERGs were found in LIHC, including 265 downregulated genes and 298 upregulated genes. KEGG pathway enrichment and GO analyses showed that DERGs were significantly enriched in rhythmic and metabolic processes. Survival analysis revealed that high expression levels of CNK1D, CSNK1E, and NPAS2 were significantly associated with the low survival rate in LIHC patients. Through cell experiment verification, the mRNA expression levels of CSNK1D, CSNK1E, and NPAS2 were found to be strongly upregulated, which was consistent with the bioinformatics analysis of LIHC patient samples. A total of 23 nodes and 135 edges were involved in the protein–protein interaction network of CSNK1D, CSNK1E, and NPAS2 genes. Clinical correlation analyses revealed that CSNK1D, CSNK1E, and NPAS2 expression levels were high-risk factors and independently connected with the overall survival rate in LIHC patients. In conclusion, the identification of these DERGs contributes to the exploration of the molecular mechanisms of LIHC occurrence and development and may be used as diagnostic and prognostic biomarkers and molecular targets for chronotherapy in LIHC patients in the future.

MOSAIC: a joint modeling methodology for combined circadian and non-circadian analysis of multi-omics data

MOTIVATION

Circadian rhythms are approximately 24-h endogenous cycles that control many biological functions. To identify these rhythms, biological samples are taken over circadian time and analyzed using a single omics type, such as transcriptomics or proteomics. By comparing data from these single omics approaches, it has been shown that transcriptional rhythms are not necessarily conserved at the protein level, implying extensive circadian post-transcriptional regulation. However, as proteomics methods are known to be noisier than transcriptomic methods, this suggests that previously identified arrhythmic proteins with rhythmic transcripts could have been missed due to noise and may not be due to post-transcriptional regulation.

RESULTS

To determine if one can use information from less-noisy transcriptomic data to inform rhythms in more-noisy proteomic data, and thus more accurately identify rhythms in the proteome, we have created the Multi-Omics Selection with Amplitude Independent Criteria (MOSAIC) application. MOSAIC combines model selection and joint modeling of multiple omics types to recover significant circadian and non-circadian trends. Using both synthetic data and proteomic data from Neurospora crassa, we showed that MOSAIC accurately recovers circadian rhythms at higher rates in not only the proteome but the transcriptome as well, outperforming existing methods for rhythm identification. In addition, by quantifying non-circadian trends in addition to circadian trends in data, our methodology allowed for the recognition of the diversity of circadian regulation as compared to non-circadian regulation.

AVAILABILITY AND IMPLEMENTATION

MOSAIC's full interface is available at https://github.com/delosh653/MOSAIC. An R package for this functionality, mosaic.find, can be downloaded at https://CRAN.R-project.org/package=mosaic.find.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Circadian Variation in Efficacy of Medications

Although much has been learned about circadian clocks and rhythms over the past few decades, translation of this foundational science underlying the temporal regulation of physiology and behavior to clinical applications has been slow. Indeed, acceptance of the modern study of circadian rhythms has been blunted because the phenomenology of cyclic changes had to counteract the 20th century dogma of homeostasis in the biological sciences and medicine. We are providing this review of clinical data to highlight the emerging awareness of circadian variation in efficacy of medications for physicians, clinicians, and pharmacists. We are suggesting that gold-standard double-blind clinical studies should be conducted to determine the best time of day for optimal effectiveness of medications; also, we suggest that time of day should be tracked and reported as an important biological variable in ongoing clinical studies hereafter. Furthermore, we emphasize that time of day is, and should be considered, a key biological variable in research design similar to sex. In common with biomedical research data that have been historically strongly skewed toward the male sex, most pharmaceutical data have been skewed toward morning dosing without strong evidence that this is the optimal time of efficacy.

In vivo flow cytometry reveals a circadian rhythm of circulating tumor cells

Circulating tumor cells (CTCs) is an established biomarker of cancer metastasis. The circulation dynamics of CTCs are important for understanding the mechanisms underlying tumor cell dissemination. Although studies have revealed that the circadian rhythm may disrupt the growth of tumors, it is generally unclear whether the circadian rhythm controls the release of CTCs. In clinical examinations, the current in vitro methods for detecting CTCs in blood samples are based on a fundamental assumption that CTC counts in the peripheral blood do not change significantly over time, which is being challenged by recent studies. Since it is not practical to draw blood from patients repeatedly, a feasible strategy to investigate the circadian rhythm of CTCs is to monitor them by in vivo detection methods. Fluorescence in vivo flow cytometry (IVFC) is a powerful optical technique that is able to detect fluorescent circulating cells directly in living animals in a noninvasive manner over a long period of time. In this study, we applied fluorescence IVFC to monitor CTCs noninvasively in an orthotopic mouse model of human prostate cancer. We observed that CTCs exhibited stochastic bursts over cancer progression. The probability of the bursting activity was higher at early stages than at late stages. We longitudinally monitored CTCs over a 24-h period, and our results revealed striking daily oscillations in CTC counts that peaked at the onset of the night (active phase for rodents), suggesting that the release of CTCs might be regulated by the circadian rhythm.

BMAL1 Knockdown Leans Epithelial-Mesenchymal Balance toward Epithelial Properties and Decreases the Chemoresistance of Colon Carcinoma Cells

The circadian clock coordinates biological and physiological functions to day/night cycles. The perturbation of the circadian clock increases cancer risk and affects cancer progression. Here, we studied how BMAL1 knockdown (BMAL1-KD) by shRNA affects the epithelial-mesenchymal transition (EMT), a critical early event in the invasion and metastasis of colorectal carcinoma (CRC). In corresponding to a gene set enrichment analysis, which showed a significant enrichment of EMT and invasive signatures in BMAL1_high CRC patients as compared to BMAL1_low CRC patients, our results revealed that BMAL1 is implicated in keeping the epithelial-mesenchymal equilibrium of CRC cells and influences their capacity of adhesion, migration, invasion, and chemoresistance. Firstly, BMAL1-KD increased the expression of epithelial markers (E-cadherin, CK-20, and EpCAM) but decreased the expression of Twist and mesenchymal markers (N-cadherin and vimentin) in CRC cell lines. Finally, the molecular alterations after BMAL1-KD promoted mesenchymal-to-epithelial transition-like changes mostly appeared in two primary CRC cell lines (i.e., HCT116 and SW480) compared to the metastatic cell line SW620. As a consequence, migration/invasion and drug resistance capacities decreased in HCT116 and SW480 BMAL1-KD cells. Together, BMAL1-KD alerts the delicate equilibrium between epithelial and mesenchymal properties of CRC cell lines, which revealed the crucial role of BMAL1 in EMT-related CRC metastasis and chemoresistance.

Telemonitored Human Circadian Temperature Dynamics During Daily Routine

BACKGROUND

Circadian rhythms in body temperature coordinate peripheral molecular clocks, hence they could potentially predict optimal treatment timing (chronotherapy) in individual patients. Circadian parameters in chest surface body temperature (Chesttemp) were recorded remotely and in real time through the use of wearable sensors.

METHODS

The dynamics of circadian oscillations in Chesttemp and core body temperature (Coretemp) and their moderation by sex and age were analysed in 38 men and 50 women, aged 21-78 years. In two studies (ST1 and ST2), Chesttemp was measured every minute and teletransmitted using a BLE-connected sensor for 3.6-28.3 days. Additionally, in ST2, Coretemp was recorded per minute in 33 age- and sex-stratified subjects using electronic ingestible pills with radio-frequency transmissions. Circadian parameters were computed using spectral analysis and cosinor modelling. The temporal relations between Chesttemp and Coretemp cosinor parameters were summarised with principal component (PC) analysis. The effect of sex and age was analysed through multivariate regression.

RESULTS

Using spectral analysis, a dominant period of 24- or 12-h was identified in 93.2% of the Chesttemp and in 100% of the Coretemp time series. The circadian parameters varied largely between-subjects both for Chesttemp (ranges: mesors, 33.2-36.6°C; amplitudes, 0.2-2.5°C; acrophases, 14:05-7:40), and Coretemp (mesors, 36.6-37.5°C; amplitudes, 0.2-0.7°C; bathyphases, 23:50-6:50). Higher PC loadings mainly corresponded to (i) large Chesttemp amplitudes, and phase advance of both temperature rhythms for the first PC (PC1, 27.2% of variance var.), (ii) high mesors in both temperature rhythms for PC2 (22.4% var.), and (iii) large Coretemp amplitudes for PC3 (12.9% var.). Chesttemp and Coretemp mesors and PC2 loadings decreased in females, while remaining quite stable in males as a function of age. In contrast, Coretemp amplitude and PC3 loadings increased with age in females, but decreased in males. Finally, older subjects, both female and male, displayed a reduction in ultradian variabilities, and an increase in both Chesttemp circadian amplitude and PC1 loadings.

INTERPRETATION

The dynamics relations between Chesttemp and Coretemp rhythms were largely moderated by age and sex, with results suggesting that treatment timing could be most critical for therapeutic index in women and in order people.

Effect of Two Interventions on Sleep Quality for Adolescent and Young Adult Cancer Survivors: A Pilot Randomized Controlled Trial

BACKGROUND

Sleep disturbance is common among adolescent and young adult (AYA) cancer survivors. Physical activity (PA) and behavioral activation (BA) therapy have been reported as enhancing sleep quality, but few studies exist on the effects of such interventions combined with technology to promote sleep quality in AYA cancer patients.

OBJECTIVE

The aim of this study was to investigate the feasibility and effects of intelligent wearable device-based PA therapy and internet-based modified BA therapy to improve sleep quality among AYA cancer patients.

METHODS

A randomized controlled trial with 143 AYA cancer patients was conducted. Participants were randomly assigned to a control group (n = 48), which performed routine care, a PA group (n = 47), which received 8-week PA therapy based on intelligent wearable devices, and a BA group (n = 48), which participated in internet-based modified BA therapy for 8 weeks.

RESULTS

At 1 week and 3 months after the intervention for sleep quality, there were statistically significant differences between the PA group and the control group (P = .020), but no statistically significant difference between the BA group and the control group.

CONCLUSIONS

The intelligent wearable device-based PA therapy has more advantages than internet-based modified BA therapy in improving the overall state of AYA cancer patients, and the intervention effect was sustained for at least 3 months.

IMPLICATIONS FOR PRACTICE

Developing and implementing PA plans for AYA cancer survivors can improve their sleep quality. Social media, intelligent wearable devices, and mobile health applications have unique advantages in promoting sleep quality for AYA cancer survivors.

A novel approach to management of sleep-associated problems in patients with breast cancer (MOSAIC) during chemotherapy : A pilot study

STUDY OBJECTIVES

This pilot randomized controlled trial (RCT) was conducted to assess the preliminary effects of Brief Behavioral Therapy for Cancer-Related Insomnia (BBT-CI) delivered by trained research staff in comparison to a sleep hygiene pamphlet control and to assess moderators of treatment effect in patients with breast cancer undergoing chemotherapy.

METHODS

Of 74 participants recruited, 37 were randomized to BBT-CI and 37 were randomized to the control condition. Trained staff members delivered the intervention during chemotherapy treatments to reduce patients' burden. Insomnia was assessed with the Insomnia Severity Index (ISI), anxiety was assessed with the Spielberger State-Trait Anxiety Inventory, symptom burden was assessed with the Symptom Inventory (SI), and study staff recorded previous treatments and surgeries received by patients.

RESULTS

Patients randomized to BBT-CI showed significantly greater improvements in their ISI scores compared to the sleep hygiene group. Additionally, several treatment moderators were identified. The effect of BBT-CI was greater among individuals with lower baseline state-trait anxiety, with previous surgery for cancer, and with higher baseline somatic symptom severity.

CONCLUSIONS

BBT-CI shows preliminary efficacy compared to the sleep hygiene handout on insomnia in cancer patients undergoing chemotherapy. A large-phase III RCT needs to be conducted to replicate the preliminary findings.

Circadian Effects of Drug Responses

Circadian rhythms describe physiological systems that repeat themselves with a cycle of approximately 24 h. Our understanding of the cellular and molecular origins of these oscillations has improved dramatically, allowing us to appreciate the significant role these oscillations play in maintaining physiological homeostasis. Circadian rhythms allow living organisms to predict and efficiently respond to a dynamically changing environment, set by repetitive day/night cycles. Since circadian rhythms underlie almost every aspect of human physiology, it is unsurprising that they also influence the response of a living organism to disease, stress, and therapeutics. Therefore, not only do the mechanisms that maintain health and disrupt homeostasis depend on our internal circadian clock, but also the way drugs are perceived and function depends on these physiological rhythms. We present a holistic view of the therapeutic process, discussing components such as disease state, pharmacokinetics, and pharmacodynamics, as well as adverse reactions that are critically affected by circadian rhythms. We outline challenges and opportunities in moving toward personalized medicine approaches that explore and capitalize on circadian rhythms for the benefit of the patient.

PER2 Circadian Oscillation Sensitizes Esophageal Cancer Cells to Chemotherapy

Simple Summary

There are growing evidences that the circadian rhythm modulates key cellular processes in physiological and pathological conditions. Here, we characterized the consequences of the daily oscillations of the clock-related gene PER2 in esophageal cancer cells and found that chemotherapy is more efficient when PER2 expression is low. These results suggest that chronotherapy might be used to potentiate the impact of current chemotherapy regimen.

Abstract

Esophageal squamous cell carcinoma (eSCC) accounts for more than 85% cases of esophageal cancer worldwide and the 5-year survival rate associated with metastatic eSCC is poor. This low survival rate is the consequence of a complex mechanism of resistance to therapy and tumor relapse. To effectively reduce the mortality rate of this disease, we need to better understand the molecular mechanisms underlying the development of resistance to therapy and translate that knowledge into novel approaches for cancer treatment. The circadian clock orchestrates several physiological processes through the establishment and synchronization of circadian rhythms. Since cancer cells need to fuel rapid proliferation and increased metabolic demands, the escape from circadian rhythm is relevant in tumorigenesis. Although clock related genes may be globally repressed in human eSCC samples, PER2 expression still oscillates in some human eSCC cell lines. However, the consequences of this circadian rhythm are still unclear. In the present study, we confirm that PER2 oscillations still occur in human cancer cells in vitro in spite of a deregulated circadian clock gene expression. Profiling of eSCC cells by RNAseq reveals that when PER2 expression is low, several transcripts related to apoptosis are upregulated. Consistently, treating eSCC cells with cisplatin when PER2 expression is low enhances DNA damage and leads to a higher apoptosis rate. Interestingly, this process is conserved in a mouse model of chemically-induced eSCC ex vivo. These results therefore suggest that response to therapy might be enhanced in esophageal cancers using chronotherapy.

Mathematical modeling of mammalian circadian clocks affecting drug and disease responses

To align with daily environmental changes, most physiological processes in mammals exhibit a time-of-day rhythmicity. This circadian control of physiology is intrinsically driven by a cell-autonomous clock gene network present in almost all cells of the body that drives rhythmic expression of genes that regulate numerous molecular and cellular processes. Accordingly, many aspects of pharmacology and toxicology also oscillate in a time-of-day manner giving rise to diverse effects on pharmacokinetics and pharmacodynamics. Genome-wide studies and mathematical modeling are available tools that have significantly improved our understanding of these nonlinear aspects of physiology and therapeutics. In this manuscript current literature and our prior work on the model-based approaches that have been used to explore circadian genomic systems of mammals are reviewed. Such basic understanding and having an integrative approach may provide new strategies for chronotherapeutic drug treatments and yield new insights for the restoration of the circadian system when altered by diseases.

Dose- and time-dependent tolerability and efficacy of organo-osmium complex FY26 and its tissue pharmacokinetics in hepatocarcinoma-bearing mice

The organo-osmium complex [OsII(ɳ6-p-cym)(PhAzPy-NMe2)I]+ (FY26) exhibits promising in vitro antitumour activity against mouse hepatocarcinoma Hepa1-6 and other mouse or human cancer cell lines. Here, we drastically enhance water solubility of FY26 through the replacement of the PF6- counter-anion with chloride using a novel synthesis method. FY26⋅PF6 and FY26⋅Cl displayed similar in vitro cytotoxicity in two cancer cell models. We then show the moderate and late anticancer efficacy of FY26⋅PF6 and FY26⋅Cl in a subcutaneous murine hepatocarcinoma mouse model. Both efficacy and tolerability varied according to FY26 circadian dosing time in hepatocarcinoma tumour-bearing mice. Tumour and liver uptake of the drug were determined over 48 h following FY26⋅Cl administration at Zeitgeber time 6 (ZT6), when the drug is least toxic (in the middle of the light span when mice are resting). Our studies suggest the need to administer protracted low doses of FY26 at ZT6 in order to optimize its delivery schedule, for example through the use of chrono-releasing nanoparticles.

A novel similarity score based on gene ranks to reveal genetic relationships among diseases

Knowledge of similarities among diseases can contribute to uncovering common genetic mechanisms. Based on ranked gene lists, a couple of similarity measures were proposed in the literature. Notice that they may suffer from the determination of cutoff or heavy computational load, we propose a novel similarity score SimSIP among diseases based on gene ranks. Simulation studies under various scenarios demonstrate that SimSIP has better performance than existing rank-based similarity measures. Application of SimSIP in gene expression data of 18 cancer types from The Cancer Genome Atlas shows that SimSIP is superior in clarifying the genetic relationships among diseases and demonstrates the tendency to cluster the histologically or anatomically related cancers together, which is analogous to the pan-cancer studies. Moreover, SimSIP with simpler form and faster computation is more robust for higher levels of noise than existing methods and provides a basis for future studies on genetic relationships among diseases. In addition, a measure MAG is developed to gauge the magnitude of association of anindividual gene with diseases. By using MAG the genes and biological processes significantly associated with colorectal cancer are detected.

A Tangled Threesome: Circadian Rhythm, Body Temperature Variations, and the Immune System

Simple Summary

In mammals, including humans, the body temperature displays a circadian rhythm and is maintained within a narrow range to facilitate the optimal functioning of physiological processes. Body temperature increases during the daytime and decreases during the nighttime thus influencing the expression of the molecular clock and the clock-control genes such as immune genes. An increase in body temperature (daytime, or fever) also prepares the organism to fight aggression by promoting the activation, function, and delivery of immune cells. Many factors may affect body temperature level and rhythm, including environment, age, hormones, or treatment. The disruption of the body temperature is associated with many kinds of diseases and their severity, thus supporting the assumed association between body temperature rhythm and immune functions. Recent studies using complex analysis suggest that circadian rhythm may change in all aspects (level, period, amplitude) and may be predictive of good or poor outcomes. The monitoring of body temperature is an easy tool to predict outcomes and maybe guide future studies in chronotherapy.

Abstract

The circadian rhythm of the body temperature (CRBT) is a marker of the central biological clock that results from multiple complex biological processes. In mammals, including humans, the body temperature displays a strict circadian rhythm and has to be maintained within a narrow range to allow optimal physiological functions. There is nowadays growing evidence on the role of the temperature circadian rhythm on the expression of the molecular clock. The CRBT likely participates in the phase coordination of circadian timekeepers in peripheral tissues, thus guaranteeing the proper functioning of the immune system. The disruption of the CRBT, such as fever, has been repeatedly described in diseases and likely reflects a physiological process to activate the molecular clock and trigger the immune response. On the other hand, temperature circadian disruption has also been described as associated with disease severity and thus may mirror or contribute to immune dysfunction. The present review aims to characterize the potential implication of the temperature circadian rhythm on the immune response, from molecular pathways to diseases. The origin of CRBT and physiological changes in body temperature will be mentioned. We further review the immune biological effects of temperature rhythmicity in hosts, vectors, and pathogens. Finally, we discuss the relationship between circadian disruption of the body temperature and diseases and highlight the emerging evidence that CRBT monitoring would be an easy tool to predict outcomes and guide future studies in chronotherapy.

Tissue physiology revolving around the clock: circadian rhythms as exemplified by the intervertebral disc

Circadian clocks in the brain and peripheral tissues temporally coordinate local physiology to align with the 24 hours rhythmic environment through light/darkness, rest/activity and feeding/fasting cycles. Circadian disruptions (during ageing, shift work and jet-lag) have been proposed as a risk factor for degeneration and disease of tissues, including the musculoskeletal system. The intervertebral disc (IVD) in the spine separates the bony vertebrae and permits movement of the spinal column. IVD degeneration is highly prevalent among the ageing population and is a leading cause of lower back pain. The IVD is known to experience diurnal changes in loading patterns driven by the circadian rhythm in rest/activity cycles. In recent years, emerging evidence indicates the existence of molecular circadian clocks within the IVD, disruption to which accelerates tissue ageing and predispose animals to IVD degeneration. The cell-intrinsic circadian clocks in the IVD control key aspects of physiology and pathophysiology by rhythmically regulating the expression of ~3.5% of the IVD transcriptome, allowing cells to cope with the drastic biomechanical and chemical changes that occur throughout the day. Indeed, epidemiological studies on long-term shift workers have shown an increased incidence of lower back pain. In this review, we summarise recent findings of circadian rhythms in health and disease, with the IVD as an exemplar tissue system. We focus on rhythmic IVD functions and discuss implications of utilising biological timing mechanisms to improve tissue health and mitigate degeneration. These findings may have broader implications in chronic rheumatic conditions, given the recent findings of musculoskeletal circadian clocks.

Temozolomide chronotherapy in patients with glioblastoma: a retrospective single-institute study

BACKGROUND

Chronotherapy is an innovative approach to improving survival through timed delivery of anti-cancer treatments according to patient daily rhythms. Temozolomide (TMZ) is a standard-of-care chemotherapeutic agent for glioblastoma (GBM). Whether timing of TMZ administration affects GBM patient outcome has not previously been studied. We sought to evaluate maintenance TMZ chronotherapy on GBM patient survival.

METHODS

This retrospective study reviewed patients with newly diagnosed GBM from January 1, 2010 to December 31, 2018 at Washington University School of Medicine who had surgery, chemoradiation, and were prescribed TMZ to be taken in the morning or evening. The Kaplan-Meier method and Cox regression model were used for overall survival (OS) analyses. The propensity score method accounted for potential observational study biases. The restricted mean survival time (RMST) method was performed where the proportional hazard assumption was violated.

RESULTS

We analyzed 166 eligible GBM patients with a median follow-up of 5.07 years. Patients taking morning TMZ exhibited longer OS compared to evening (median OS, 95% confidence interval [CI] = 1.43, 1.12-1.92 vs 1.13, 0.84-1.58 years) with a significant year 1 RMST difference (-0.09, 95% CI: -0.16 to -0.018). Among MGMT-methylated patients, median OS was 6 months longer for AM patients with significant RMST differences at years 1 (-0.13, 95% CI = -0.24 to -0.019) to 2.5 (-0.43, 95% CI = -0.84 to -0.028). Superiority of morning TMZ at years 1, 2, and 5 (all P < .05) among all patients was supported by RMST difference regression after adjusting for confounders.

CONCLUSIONS

Our study presents preliminary evidence for the benefit of TMZ chronotherapy to GBM patient survival. This impact is more pronounced in MGMT-methylated patients.

Circadian regulation of transporter expression and implications for drug disposition

Introduction: Solute Carrier (SLC) and ATP-binding cassette (ABC) transporters expressed in the intestine, liver, and kidney determine the absorption, distribution, and excretion of drugs. In addition, most molecular and cellular processes show circadian rhythmicity controlled by circadian clocks that leads to diurnal variations in the pharmacokinetics and pharmacodynamics of many drugs and affects their therapeutic efficacy and toxicity.Area covered: This review provides an overview of the current knowledge on the circadian rhythmicity of drug transporters and the molecular mechanisms of their circadian control. Evidence for coupling drug transporters to circadian oscillators and the plausible candidates conveying circadian clock signals to target drug transporters, particularly transcription factors operating as the output of clock genes, is discussed.Expert opinion: The circadian machinery has been demonstrated to interact with the uptake and efflux of various drug transporters. The evidence supports the concept that diurnal changes that affect drug transporters may influence the pharmacokinetics of the drugs. However, more systematic studies are required to better define the timing of pharmacologically important drug transporter regulation and determine tissue- and sex-dependent differences. Finally, the transfer of knowledge based on the results and conclusions obtained primarily from animal models will require careful validation before it is applied to humans.

Metallodrugs are unique: opportunities and challenges of discovery and development

Metals play vital roles in nutrients and medicines and provide chemical functionalities that are not accessible to purely organic compounds. At least 10 metals are essential for human life and about 46 other non-essential metals (including radionuclides) are also used in drug therapies and diagnostic agents. These include platinum drugs (in 50% of cancer chemotherapies), lithium (bipolar disorders), silver (antimicrobials), and bismuth (broad-spectrum antibiotics). While the quest for novel and better drugs is now as urgent as ever, drug discovery and development pipelines established for organic drugs and based on target identification and high-throughput screening of compound libraries are less effective when applied to metallodrugs. Metallodrugs are often prodrugs which undergo activation by ligand substitution or redox reactions, and are multi-targeting, all of which need to be considered when establishing structure-activity relationships. We focus on early-stage in vitro drug discovery, highlighting the challenges of evaluating anticancer, antimicrobial and antiviral metallo-pharmacophores in cultured cells, and identifying their targets. We highlight advances in the application of metal-specific techniques that can assist the preclinical development, including synchrotron X-ray spectro(micro)scopy, luminescence, and mass spectrometry-based methods, combined with proteomic and genomic (metallomic) approaches. A deeper understanding of the behavior of metals and metallodrugs in biological systems is not only key to the design of novel agents with unique mechanisms of action, but also to new understanding of clinically-established drugs.

Do malignant cells sleep at night?

Biological rhythms regulate the biology of most, if not all living creatures, from whole organisms to their constitutive cells, their microbiota, and also parasites. Here, we present the hypothesis that internal and external ecological variations induced by biological cycles also influence or are exploited by cancer cells, especially by circulating tumor cells, the key players in the metastatic cascade. We then discuss the possible clinical implications of the effect of biological cycles on cancer progression, and how they could be exploited to improve and standardize methods used in the liquid biopsy field.

Chronotoxicity of Streptomycin-Induced Renal Injury in Mice

The aim of the present study was to investigate the "chronotoxicity" of streptomycin (SM) in relation to its circadian periodicity. Male ICR mice were injected intraperitoneally with SM (780 mg/kg, one shot) one of six time points throughout the day. Mortality was monitored until 14 d after the injection and clearly differed depending on the timing of the injection (i.e., mice were more sensitive to injection during the dark phase). Moreover, when mice were administered with non-lethal doses of SM (550 mg/kg, every 24 h for 3 d, in the light phase or dark phase), the levels of nephrotoxicity indicators (blood urea nitrogen and renal levels of malondialdehyde and cyclooxygenase-2) were significantly increased by the injection in the dark phase, but not in the light phase. These results suggested that SM showed clear chronotoxicity. Our current data indicated that chronotoxicology may provide valuable information on the importance of injection timings for evaluations of toxicity and undesirable side effects.

Investigation of treatment-time differences in colistin-induced nephrotoxicity in Wistar rats

Colistin-induced nephrotoxicity (CIN) occurs in up to 60% of patients, and this has restricted its clinical use. In view of its efficacy amidst the rising challenge of infections caused by multidrug-resistant bacteria, current studies are focusing on ways to ameliorate colistin-induced nephrotoxicity. This study investigated treatment-time differences in colistin-induced nephrotoxicity in Wistar rats. A dose of 600,000 IU/Kg/day of colistimethate sodium (CMS) was administered to male Wistar rats to induce nephrotoxicity; the rats tolerated the higher dose for the treatment duration with higher mean values of serum creatinine, urea, and malondialdehyde compared to the group that received 450,000 IU/Kg/day CMS (p ≤ 0.05). Four groups (n = 8/group) of rats received intraperitoneal (i.p.) injections of 600,000 IU/Kg/day CMS each at four equally spaced circadian times (00:00, 06:00, 12:00, and 18:00 h) to determine the time of administration with least renal toxicity. Biomarkers of oxidative stress and renal toxicity were measured and kidney histology studied after the treatments. The results showed a 24-h pattern in nephrotoxicity from CIN, and that treatment during the activity time period (dark phase) caused lowest CIN. Histological findings supported this finding, with photomicrographs consistently showing more pronounced features of CIN in the groups treated during time frame that coincided with the rest phase in rats (12:00 and 18:00).

An Optimal Time for Treatment-Predicting Circadian Time by Machine Learning and Mathematical Modelling

Tailoring medical interventions to a particular patient and pathology has been termed personalized medicine. The outcome of cancer treatments is improved when the intervention is timed in accordance with the patient's internal time. Yet, one challenge of personalized medicine is how to consider the biological time of the patient. Prerequisite for this so-called chronotherapy is an accurate characterization of the internal circadian time of the patient. As an alternative to time-consuming measurements in a sleep-laboratory, recent studies in chronobiology predict circadian time by applying machine learning approaches and mathematical modelling to easier accessible observables such as gene expression. Embedding these results into the mathematical dynamics between clock and cancer in mammals, we review the precision of predictions and the potential usage with respect to cancer treatment and discuss whether the patient's internal time and circadian observables, may provide an additional indication for individualized treatment timing. Besides the health improvement, timing treatment may imply financial advantages, by ameliorating side effects of treatments, thus reducing costs. Summarizing the advances of recent years, this review brings together the current clinical standard for measuring biological time, the general assessment of circadian rhythmicity, the usage of rhythmic variables to predict biological time and models of circadian rhythmicity.

Comparing Conventional Chemotherapy to Chronomodulated Chemotherapy for Cancer Treatment: Protocol for a Systematic Review

BACKGROUND

Chronomodulated chemotherapy aims to achieve maximum drug safety and efficacy by adjusting the time of treatment to an optimal biological time as determined by the circadian clock. Although it is a promising alternative to conventional (non-time-stipulated) chemotherapy in several instances, the lack of scientific consensus and the increased logistical burden of timed administration limit the use of a chronomodulated administration protocol.

OBJECTIVE

With the goal to increase scientific consensus on this subject, we plan to conduct a systematic review of the current literature to compare the drug safety and efficacy of chronomodulated chemotherapy with those of conventional chemotherapy.

METHODS

This systematic review will comply with the PRISMA (Preferred Reporting Items for the Systematic Reviews and Meta-Analysis) guidelines. In order to identify relevant studies, we conducted a comprehensive search in PubMed and Embase on May 18, 2020. We included clinical studies that compare either the safety or efficacy of chronomodulated chemotherapy with that of conventional chemotherapy. Potential studies will be reviewed and screened by 2 independent reviewers. Quality assessment will be performed using the National Institutes of Health's Study Quality Assessment Tool (Quality Assessment of Controlled Intervention Studies). Disagreements will be resolved by consulting a third independent reviewer.

RESULTS

This protocol has received funding, and the search for studies from databases commenced on May 18, 2020. The systematic review is planned to be completed by October 31, 2020.

CONCLUSIONS

In this systematic review, we will compare drug safety and drug efficacy for cancer patients who were administered either chronomodulated chemotherapy or conventional chemotherapy. Moreover, we will highlight the outcomes and quality of the selected trials for this review.

TRIAL REGISTRATION

PROSPERO International Prospective Register of Systematic Reviews CRD42020177878; https://tinyurl.com/y53w9nq6.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/18023.

Effect of the Interaction Between Cadmium Exposure and CLOCK Gene Polymorphisms on Thyroid Cancer: a Case-Control Study in China

The exposure to endocrine disruptors and the disruption of the circadian rhythms can both affect thyroid hormones, with results that are most likely carcinogenic in humans. The effects of cadmium (Cd) level and circadian-related single-nucleotide polymorphisms (SNPs) on thyroid cancer (TC) risk have rarely been reported. In this study, the associations of urine Cd, CLOCK gene polymorphisms, and TC risk were evaluated, in addition to the effect of the gene-environment interaction on TC risk. In this case-control study, 218 TC cases and 218 controls were enrolled. Cd in urinary samples was determined by atomic absorption spectrometry. Three SNPs (rs3805151, rs3805154, and rs78929565) were genotyped with an improved multiplex ligation detection reaction technique. The individuals with a high Cd level were 1.72-fold more likely to have TC (OR = 1.72, 95%CI 1.04-2.85), and a high Cd level was associated with higher tumor T stage and N stage (OR = 2.42, 95%CI 1.28-4.58; OR = 3.26, 95%CI 1.67-6.33, respectively). Individuals with TT genotype of rs78929565 had a 107 % increase in TC risk (OR = 2.07, 95%CI 1.00-4.29). Cases with CT genotype tended to have a higher AJCC stage (OR = 2.79, 95% CI 1.01-7.78). A significant interaction was detected between the rs78929565 variant and Cd exposure (p interaction = 0.04). The TT genotype carriers of rs78929565 with a high Cd level were more susceptible to thyroid cancer than the major homozygotes carriers who were exposed to a low cadmium level (OR = 2.66, 95%CI 1.07-6.59). These findings suggested that Cd exposure and the CLOCK variant genotypes were associated with TC risk and tumor severity. Individuals with minor allele of rs78929565 and higher Cd exposure had increased susceptibility to TC. Further studies are required to confirm these findings.