Beata U.

Authors: Frédéric Thomas, Randolph M. Nesse, Robert Gatenby, Cindy Gidoin, François Renaud, Benjamin Roche, Beata Ujvari

Source: Trends in Cancer, Volume 2, Issue 8, p409–415, August 2016

Brief summary of the paper: There is striking variation in the incidence of cancer in human organs. Malignant tumors are common in the colon and breast but rare in the heart and small bowel. The uterus frequently develops benign fibroid tumors but uterine cancers are relatively rare. The organ-specific difference in cancer prevalence has been explained primarily by the relative roles of intrinsic and extrinsic risk factors.

In this opinion article, we propose also considering organs as distinct but connected ecosystems whose different vulnerabilities to malignant transformation may be partially explained by how essential each organ is for survival through the age of reproduction. We present and discuss some of the basic concepts and assumptions of this perspective on evolutionary medicine.

SPEAKER: Associate Professor Janine Deakin, Institute for Applied Ecology, University of Canberra

DATE: Friday, 12th August 2016
LOCATION: Geelong Campus at Waurn Ponds, Room KA4.207
TIME: 1:30pm
Seminar will also be video linked to the following campuses: Melbourne Campus at Burwood, Burwood Corporate Centre (BCC) and Warrnambool Campus, Room J2.22

External visitors – wish to join us and connect to our seminars?

• You may connect to the live seminar via *N SEBE VMP LES Seminars 52236958@deakin.edu.au [ID.36958] or via the methods listed HERE.
• For Deakin staff and students, please join via Skype for Business (Lync).
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ABSTRACT: Tasmanian devils are currently under the threat of extinction in the wild due to a transmissible tumour known as devil facial tumour (DFT) disease. The unusual feature of this disease is that the tumour cells themselves are the infectious agent, being spread when devils bite each other during social interactions.

By studying DFT chromosomes, it has been possible to trace the evolution of this tumour as it spreads through the population. The comparison of different DFT strains has provided important insight into the evolution of this infectious agent and is helping to determine whether there is a chance of the tumour evolving to a point where devils will be able to survive DFT infections, permitting the survival of the population in the wild.

Cases of transmissible cancers are rare but it appears that a second transmissible facial tumour (DFT2) has been identified in individuals from southern Tasmania. DFT2 is genetically distinct from DFT1. The emergence of a second transmissible tumour raises the questions about the origin of transmissible tumours. Is there something about devils that makes them susceptible to developing these diseases? I will discuss the work my team has been doing on both transmissible tumours.

BIO: Janine is an Associate Professor in the Institute for Applied Ecology at the University of Canberra. She received her PhD in Biology from Macquarie University.

She then carried out postdoctoral research at the University of Texas Health Science Center at San Antonio before returning to Australia to take up a research position at ANU in the Comparative Genomics group.

In 2010, Janine was awarded an ARC Future Fellowship to track the evolution of devil facial tumours but also has research projects on other native Australian species, such as chromosomal speciation in rock-wallabies and sex determination in the central bearded dragon.

Appointments with guest speaker may be made via Beata Ujvari.

SPEAKER: Professor Arthur Georges, Institute for Applied Ecology, University of Canberra, ACT

DATE: Friday, 29th July 2016
LOCATION: Geelong Campus at Waurn Ponds, Room KA4.207
TIME: 1:30pm
Seminar will also be video linked to the following campuses: Melbourne Campus at Burwood, Burwood Corporate Centre (BCC) and Warrnambool Campus, Room J2.22

External visitors – wish to join us and connect to our seminars?

• You may connect to the live seminar via *N SEBE VMP LES Seminars52236958@deakin.edu.au [ID.36958], or via the methods listed HERE.
• For Deakin staff and students, please join via Skype for Business (Lync).
• Could not log in? More info on how to connect is available HERE.
• Please note that connection is only available while a seminar is taking place. See exact times.

As a courtesy, we request that when connecting to the seminar that you mute your microphone unless you are required to speak, this would ensure that the sound from the speaker to the audience is not disrupted by feedback from your microphone – thank you!

ABSTRACT: Although phenotype is governed by underlying genotype, the translation of the genetic blueprint to traits possessed by the individual is under varying degrees of environmental influence, leading to phenotypic variation in traits with a common genetic underpinning.

Sex of an individual, at least in vertebrates, was once thought to be strictly determined by the complement of chromosomes passed to the offspring from the parents. The prevailing view of a 1:1 correspondence between genotype and sexual phenotype (genetic sex determination or GSD) that is so prevalent in mammals and birds, fell away with the discovery of astonishing diversity in the mechanisms of sex determination of many lineages of reptile and fish.

Environmental sex determination is now well established in these groups, and temperature early in development is the primary factor involved (hence, temperature-dependent sex determination, or TSD). Indeed, sex determination in reptiles is seen as one of the most profound examples of developmental plasticity among vertebrates.

Furthermore, it falls in a special class of phenotypic plasticity, along with castes in bees and winged/winglessness in aphids – a polyphenism with two states, whereby intermediate forms are either not viable or with severely compromised fitness.

In this presentation, the focus will be on a special case of sex determination where genotype and environment interact to determine sex, and discuss the mechanisms by which temperature may bring influence.

The dragon lizard, Pogona vitticeps, has well defined sex chromosomes – a ZZ/ZW system as in birds – yet temperature can over-ride the genetic signal to reverse the ZZ male trajectory to a female phenotype, both in the laboratory and in the wild.

This is one example where developmental plasticity can drive rapid evolutionary responses to changing climate, responses that challenge our understanding of the evolution of temperature-dependent sex determination.

BIO: Professor Arthur Georges is an ecologist and herpetologist whose research interests lie in the evolution, ecology and systematics of Australian reptiles. A fundamental interest in these fascinating animals takes him into the field and the laboratory to learn more of their biology and to apply what he has learned in solving contemporary challenges for their conservation.

Arthur recently led the consortium to generate an annotated genome sequence for the Australian dragon lizard, Pogona vitticeps, which he and his team are using to probe the intricacies of sex determination in reptiles.

Appointments with guest speaker may be made via Beata Ujvari.

Beata U.

Title: Do cell-autonomous and non-cell-autonomous effects drive the structure of tumor ecosystems?

Authors: Tissot, T; Ujvari, B; Solary, E; Lassus, P; Roche, B; Thomas, F

Source: BIOCHIMICA ET BIOPHYSICA ACTA-REVIEWS ON CANCER, 1865 (2):147-154, APR 2016

Brief summary of the paper: By definition, a driver mutation confers a growth advantage to the cancer cell in which it occurs, while a passenger mutation does not: the former is usually considered as the engine of cancer progression, while the latter is not.

Actually, the effects of a given mutation depend on the genetic background of the cell in which it appears, thus can differ in the subclones that form a tumor. In addition to cell-autonomous effects generated by the mutations, non-cell-autonomous effects shape the phenotype of a cancer cell.

Here, we review the evidence that a network of biological interactions between subclones drives cancer cell adaptation and amplifies intra-tumor heterogeneity. Integrating the role of mutations in tumor ecosystems generates innovative strategies targeting the tumor ecosystem’s weaknesses to improve cancer treatment.

Strong representation by the WGG (Wild Genes Group) at the SMBE 2016 – the annual meeting of the Society for Molecular Biology and Evolution at the Gold Coast Convention & Exhibition Centre, Queensland, Australia (@OfficialSMBE).

A big ‘thank you’ to SMBE for awarding Kimberly Pinch and Nynke Raven with student travel awards and making it possible for them to attend SMBE 2016!

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