Do malignant cells sleep at night?

Authors: Luis Enrique Cortés-Hernández, Zahra Eslami-S, Antoine M. Dujon, Mathieu Giraudeau, Beata Ujvari, Frédéric Thomas & Catherine Alix-Panabières

Source: Genome Biology (NOV 2020)

Brief summary of the paper:

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.

Unravelling the cancer puzzle from an ecological and evolutionary perspective – an Australian and French International Associated Laboratory

In case you’ve missed this, a recording of the conference – “Unravelling the cancer puzzle from an ecological and evolutionary perspective – an Australian and French International Associated Laboratory” – is now available online. Click HERE to watch the recording.

Presenters Professor Frédéric Thomas (CNRS, France) and Associate Professor Beata Ujvari (Deakin University) will focus on how applying evolutionary principles to cancer revolutionises treatment strategies and approaches.

The Melbourne Salon is a joint venture between RMIT University, the Institute for the Study of French-Australian Relations and the Alliance Française de Melbourne. It is a place where curious and open-minded people can engage in French-Australian cross-cultural dialogues with the aim of broadening the understanding of French and Australian perspectives on contemporary topics through conversation, debate and discussion.

Genetic rescue restores long-term viability of an isolated population of adders (Vipera berus)

Authors: Thomas Madsen; Jon Loman; Lewis Anderberg; Håkan Anderberg; Arthur Georges & Beata Ujvari

Source: Current Biology (NOV 2020)

Brief summary of the paper:

Climate change is regarded as a major threat to global biodiversity [1]. However, another key driver of declines in biodiversity during the last century has been, and still is, the devastating impact of anthropogenic habitat destruction.

Human degradation of natural habitats has resulted in large, formerly homogeneous areas becoming exceedingly isolated and fragmented, resulting in reduced genetic diversity and a concomitant increased vulnerability to pathogens and increased risk of inbreeding.

In order to restore genetic diversity in small isolated or fragmented populations, genetic rescue — that is, an intervention in which unrelated individuals are brought into a population, leading to introduction of novel alleles — has been shown to reduce the deleterious effects of inbreeding

Cancer risk landscapes: A framework to study cancer in ecosystems

Authors: Antoine M. Dujon; Beata Ujvari; FrédéricThomas

Source: Science of The Total Environment (OCT 2020)

Brief summary of the paper:

Cancer is a family of diseases that has been documented in most metazoan species and ecosystems. Human induced environmental changes are increasingly exposing wildlife to carcinogenic risk factors, and negative repercussions on ecosystems and on the conservation of endangered species are already been observed.

It is therefore of key importance to understand the spatiotemporal variability of those risk factors and how they interact with the biosphere to mitigate their effects.

Here we introduce the concept of cancer risk landscape that can be applied to understand how species are exposed to, interact with, and modify cancer risk factors.

With this publication we aim to provide a framework in order to stimulate a discussion on how to mitigate cancer-causing risk factors.

Ecological and evolutionary consequences of anticancer adaptations

Authors: Justine BOUTRY; Antoine DUJON; G.E.R.A.R.D. Anne-Lise; Sophie TISSOT; Nick MACDONALD; Aaron SCHULTZ; Peter A. BIRO; Christa BECKMANN; Rodrigo HAMEDE; David G. HAMILTON; Mathieu GIRAUDEAU; Beata UJVARI; Frédéric THOMAS

Source: iScience (Oct 2020)

Brief summary of the paper:

Cellular cheating leading to cancers exists in all branches of multicellular life, favoring the evolution of adaptations to avoid or suppress malignant progression, and/or to alleviate its fitness consequences.

Ecologists have until recently largely neglected the importance of cancer cells for animal ecology, presumably because they did not consider either the potential ecological or evolutionary consequences of anticancer adaptations.

Here, we review the diverse ways in which the evolution of anticancer adaptations has significantly constrained several aspects of the evolutionary ecology of multicellular organisms at the cell, individual, population, species and ecosystem levels, and suggest some avenues for future research.

Long term effects of outbreeding: experimental founding of island population eliminates malformations and improves hatching success in sand lizards

Authors: Willow R. Lindsay; Thomas Madsen; Erik Wapstra; Mette Lillie; Lisa Loeb; Beata Ujvari; Mats Olsson

Source: BIOLOGICAL CONSERVATION (Jul 2020)

Brief summary of the paper:

Loss of genetic variation is an increasing problem in many natural populations as a result of population fragmentation, inbreeding, and genetic drift, which may lead to inbreeding depression and subsequent “extinction vortices”. In such cases, outbreeding offers a potential population saviour from extinction.

Here we compare offspring viability between an experimentally founded outbred island population of sand lizards Lacerta agilis, and an inbred mainland source population on the Swedish West coast.

We have studied the mainland population for over a decade during which >4000 offspring from >500 parents were monitored. We conducted an outbreeding experiment in which lizards from the mainland population with relatively low genetic variation were crossbred with lizards from distant populations that lack gene flow.

The resulting 454 offspring were introduced to an otherwise uninhabited island with ideal sand lizard habitat. A survey of the island two decades later showed that offspring produced by females from the experimentally founded population had 13% higher hatching success (99.3% versus 86.4%) and elimination of the malformations occurring in 21% of clutches in the mainland source population.

These results co-occur with higher genetic diversity. We conclude that outbreeding improved offspring viability in our island population ca 5–6 generations after the founding event, that is, with sustained viability effects at a time when heterotic effects are expected to have subsided.

Darwin, the devil, and the management of transmissible cancers

Authors: Rodrigo Hamede; Thomas Madsen; Hamish McCallum; Andrew Storfer; Paul A. Hohenlohe; Hannah Siddle; Jim Kaufman; Mathieu Giraudeau; Menna Jones; Frédéric Thomas & Beata Ujvari

Source: Conservation Biology (SEP 2020)

Brief summary of the paper:

Evolutionary processes related to pathogens and functional genomics provide new tools for infectious disease management in the wild.

The ecology and evolution of wildlife cancers: Applications for management and conservation

Authors: Rodrigo Hamede, Rachel Owen, Hannah Siddle, Sarah Peck, Menna Jones, Antoine M. Dujon, Mathieu Giraudeau, Benjamin Roche, Beata Ujvari, Frédéric Thomas

Source: Evolutionary Applications (MAR 2020)

Brief summary of the paper:

Ecological and evolutionary concepts have been widely adopted to understand host–pathogen dynamics, and more recently, integrated into wildlife disease management.

Cancer is a ubiquitous disease that affects most metazoan species; however, the role of oncogenic phenomena in eco‐evolutionary processes and its implications for wildlife management and conservation remains undeveloped.

Despite the pervasive nature of cancer across taxa, our ability to detect its occurrence, progression and prevalence in wildlife populations is constrained due to logistic and diagnostic limitations, which suggests that most cancers in the wild are unreported and understudied. Nevertheless, an increasing number of virus‐associated and directly transmissible cancers in terrestrial and aquatic environments have been detected. Furthermore, anthropogenic activities and sudden environmental changes are increasingly associated with cancer incidence in wildlife.

This highlights the need to upscale surveillance efforts, collection of critical data and developing novel approaches for studying the emergence and evolution of cancers in the wild. Here, we discuss the relevance of malignant cells as important agents of selection and offer a holistic framework to understand the interplay of ecological, epidemiological and evolutionary dynamics of cancer in wildlife.

We use a directly transmissible cancer (devil facial tumour disease) as a model system to reveal the potential evolutionary dynamics and broader ecological effects of cancer epidemics in wildlife. We provide further examples of tumour–host interactions and trade‐offs that may lead to changes in life histories, and epidemiological and population dynamics.

Within this framework, we explore immunological strategies at the individual level as well as transgenerational adaptations at the population level. Then, we highlight the need to integrate multiple disciplines to undertake comparative cancer research at the human–domestic–wildlife interface and their environments.

Finally, we suggest strategies for screening cancer incidence in wildlife and discuss how to integrate ecological and evolutionary concepts in the management of current and future cancer epizootics.

Spontaneous activity rates and resting metabolism: Support for the allocation model of energy management at the among‐individual level

Authors: Peter A. Biro, Frédéric Thomas, Beata Ujvari, Bart Adriaenssens & Christa Beckmann

Source: ETHOLOGY (JAN 2020)

Brief summary of the paper:

Despite continuing interest in the proximate energetic constraints on individual variation in behavior, there is presently equivocal evidence for correlations between metabolism and behavior at the among‐individual level.

Possible reasons for this include imprecise estimates of individual mean behavior and metabolism due to no repeated measures on one or more of the traits, analyses that do not take into account the labile nature of these traits and the uncertainty in individual estimates, and changing environmental conditions not accounted for.

Predicted mean values for individual activity rate and resting metabolic rate (RMR), and associated SE’s for each, as extracted from the bivariate mixed‐effects model. Values are expressed as deviations from the mean level model and are in units of standard deviations due to data standardization to mean zero and SD = 1. The overall average mass‐corrected RMR was 184 mg O2/g/h (range = 138–240 among individuals)

In this empirical study, we repeatedly measured activity rates and resting metabolic rates (RMR) of individual male mosquitofish over an extended period, lasting several months under constant laboratory conditions. Repeatability of each trait was significant (RMR:  = .41; activity:  = .72), indicating consistent variation among individuals, making covariance between them possible. Contrary to expectations, bivariate mixed model analysis revealed that more active individuals had lower RMR ( = −.58) after accounting for mass effects and other covariates.

This result suggests that high activity rates require individuals to allocate less energy toward maintenance, and thus provides evidence for the “allocation” model of energy management. We suggest that it would be valuable to study whether and how behavior‐RMR correlations change over individual lifetime, a topic that has yet to be addressed.