Ecological and evolutionary consequences of anticancer adaptations

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

Data analysis: Tumors alter life-history traits in the freshwater cnidarian, Hydra oligactis

Table S1 : The formulas of the different generalized linear mixed models constructed and the associated value of AICc's weights, related to the analysis of the traits related to asexual reproduction (i.e. budding rate, budding type, and gap between two reproductive episodes) First, there is the results for the random effect selection and then for the fixed effects selection. NC indicates that the model has not converged

Data analysis: Tumors alter life-history traits in the freshwater cnidarian, Hydra oligactis

Table S1 : The formulas of the different generalized linear mixed models constructed and the associated value of AICc's weights, related to the analysis of the traits related to asexual reproduction (i.e. budding rate, budding type, and gap between two reproductive episodes) First, there is the results for the random effect selection and then for the fixed effects selection. NC indicates that the model has not converged

The Nicotiana tabacum ABC transporter NtPDR3 secretes O-methylated coumarins in response to iron deficiency

Although iron is present in large amounts in the soil, its poor solubility means that plants have to use various strategies to facilitate its uptake. In this study, we show that expression of NtPDR3/NtABCG3, a Nicotiana tabacum plasma-membrane ABC transporter in the pleiotropic drug resistance (PDR) subfamily, is strongly induced in the root epidermis under iron deficiency conditions. Prevention of NtPDR3 expression resulted in N. tabacum plants that were less tolerant to iron-deficient conditions, displaying stronger chlorosis and slower growth than those of the wildtype when not supplied with iron. Metabolic profiling of roots and root exudates revealed that, upon iron deficiency, secretion of catechol-bearing O-methylated coumarins such as fraxetin, hydroxyfraxetin, and methoxyfraxetin to the rhizosphere was compromised in NtPDR3-silenced plants. However, exudation of flavins such as riboflavin was not markedly affected by NtPDR3-silencing. Expression of NtPDR3 in N. tabacum Bright Yellow-2 (BY-2) cells resulted in altered intra- and extracellular coumarin pools, supporting coumarin transport by this transporter. The results demonstrate that N. tabacum secretes both coumarins and flavins in response to iron deficiency and that NtPDR3 plays an essential role in the plant response to iron deficiency by mediating secretion of O-methylated coumarins to the rhizosphere

Can UV radiation and cadmium exposures induce tumors in freshwater invertebrates ?

International audienceBecause ecosystems on our planet are now polluted by mutagenic substances to a greater extent than ever before, it is increasingly suggested that human activities are oncogenic for wildlife species. To improve our knowledge on these timely issues, experimental evidence should however complete correlative field studies. Hydras and Planarians are freshwater invertebrates which sometimes develop tumors. Hydras tumors are able to be vertically transmitted during asexual reproduction. Because the etiology of these atypical tumors is unknown, our objective is to explore the extent to which they could be, at least partially, linked to human activities. Specifically, this project aims at testing if UV radiation (both UV-A and UV-B) and/or cadmium exposure can promote tumorigenesis, and to evaluate how transmissible these inducible tumors are. A second objective is to explore the extent to which UV & cadmium exposures induce tumors in planarians. This project not only represents an original contribution to the field of ecology in human-altered habitats, but also improves our knowledge on the evolutionary ecology of transmissible malignant cell lines, and host-tumor interactions

A review of the methods used to induce cancer in invertebrates to study its effects on the evolution of species and ecosystem functioning

International audience1. Cancer is an understudied but important process in wildlife that is predicted to have a significant effect on the evolution of metazoan species due to negative effects on host fitness. However, gaining understanding of the impact of cancer on species and ecosystems is currently relatively slow as the development of both animal models in which cancer can be induced and experiments that can be performed in an ecological setting are required. Invertebrates, because they are widely available and relatively easy to manipulate, are promising animal models. In this review we examine how tumours can be induced in invertebrates to use them as experimental models to study the effects of cancer on the ecology and evolution of species. We identified four main groups of invertebrates (planarian, bivalves, hydra and drosophila) in which such inductions are performed. We then reviewed the types and effectiveness of the methods employed to induce tumours in those groups. Cancer alters the phenotype of the host. We review how experiments using invertebrate models can be used to investigate the impact of cancer on tumour-bearing individuals for their movement, reproduction, feeding behaviours, social interactions, holobiont and predation risk.We provide recommendations to facilitate the development of new invertebrate models. We also highlight a series of key questions on the ecology and evolution of cancer that could be answered with the use of invertebrate models

Changes in plastic ingestion by yellow-legged gulls (Larus michahellis) over the breeding season

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Spontaneously occurring tumors in different wild-derived strains of hydra

Abstract Hydras are freshwater cnidarians widely used as a biological model to study different questions such as senescence or phenotypic plasticity but also tumoral development. The spontaneous tumors found in these organisms have been so far described in two female lab strains domesticated years ago (Hydra oligactis and Pelmatohydra robusta) and the extent to which these tumors can be representative of tumors within the diversity of wild hydras is completely unknown. In this study, we examined individuals isolated from recently sampled wild strains of different sex and geographical origin, which have developed outgrowths looking like tumors. These tumefactions have common features with the tumors previously described in lab strains: are composed of an accumulation of abnormal cells, resulting in a similar enlargement of the tissue layers. However, we also found diversity within these new types of tumors. Indeed, not only females, but also males seem prone to form these tumors. Finally, the microbiota associated to these tumors is different from the one involved in the previous lineages exhibiting tumors. We found that tumorous individuals hosted yet undescribed Chlamydiales vacuoles. This study brings new insights into the understanding of tumor susceptibility and diversity in brown hydras from different origins