by ecancer reporter Clare Sansom

The conference of the International Institute for Anticancer Research (IIAR) took place from the 6-10 October 2014 at the prestigious (and now just off season) Porto Carras Meliton Hotel in Sidonika, Greece.

This conference series, which began 1995 and was last held on the island of Kos in 2008, now covers almost every aspect of basic and clinical cancer research.

The ninth conference is held under the auspices of the IIAR and twenty-four other national and specialist cancer societies, most based in Europe; before it ends it will have featured well over 700 presented abstracts arranged in a total of 79 separate sessions.

The principal organiser of this conference series since its beginning has been the tireless John Delinasios, director of the IIAR and editor of the journal Anticancer Research.

Franco Muggia of New York University Langone Medical Center, New York, USA, praised Delinasios – a collaborator of many years’ standing – for his commitment to building dialogue between basic and clinical cancer researchers across the world, and for his breadth of knowledge and wide network of contacts.

Muggia was the first speaker in one of the first clinical sessions of the congress, which took a new look at chemotherapy drugs.

In a wide-ranging overview, he described how endometrial cancer was rare among solid tumours in being well treated with surgery only, and how the relatively few patients who needed systemic treatment can benefit from well-established chemotherapy agents including platinum-containing drugs and taxanes.

A series of Phase III clinical trials in advanced or recurrent endometrial cancer has established carboplatin and paclitaxel, with or without doxorubicin, as the standard of care.

However, the patient population is changing, with a higher percentage of older patients, obese patients and patients with co-morbidities and further trials are needed to determine the best treatment for these.

Ola Brodin from the Karolinska Institute, Stockholm, Sweden gave an interesting presentation of the first clinical trial of a form of selenium as an anti-cancer agent.

Selenium is an important trace element for humans, and an essential component of about 25 of our proteins, although high doses are toxic.

This Phase I trial, SECAR, set out to determine the maximum tolerated dose of sodium selenite.

A small number of patients with confirmed carcinomas who were also receiving chemotherapy were given the selenium salt for two to four weeks.

The results of this trial established a maximum tolerated dose of 10.2 mg/m2 and there seemed to be some indication of efficacy: fourteen patients achieved stable disease, and there was one full remission: a phase II trial is planned.

Other talks in this session covered poly-chemotherapy regimens for exocrine pancreatic cancer, which has an extremely poor prognosis, and the use of 90Y in brachytherapy.

The afternoon’s sessions included a wide-ranging and well attended one covering oncogenes, tumour suppressors, growth factors and signal transduction.

Firstly, Dean Felsher of Stanford University, CA, USA introduced the concept of “oncogene addiction”, which suggests that inactivating some but not all oncogenes will always lead to cellular senescence or apoptosis.

He proposed that the Myc would have these properties, and described a transgenic mouse model developed in his group in which this gene can be reversibly inactivated.

Results from this model suggest that a healthy immune system is necessary for Myc inactivation to cause tumour regression.

Roche-Philippe Charles from Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA described the mutational landscape of anaplastic thyroid carcinoma (ATC), which is the most aggressive form of thyroid cancer.

Only about 5% of thyroid tumours are classified as anaplastic, but these are hard to treat and responsible for many more cancer deaths than papillary or follicular thyroid cancer.

The V600E mutation of the proto-oncogene BRAF is found in 25% of anaplastic thyroid cancers, where it is frequently found in combination with mutations in the catalytic subunit of PI3 kinase.

Transgenic mice bearing mutations in both these genes rapidly develop dense cellular thyroid carcinomas that dramatically increase the volume of the thyroid.

Charles suggested that this mouse model forms an excellent pre-clinical platform for testing drugs against ATC or other tumours that bear these mutations.

Arun Seth from Ontario Institute of Cancer Research, Canada, who co-chaired the session with Felscher, described a mouse model of bone metastasis from breast cancer in which mouse flanks were implanted with healthy bone taken from women undergoing hip replacements as well as with human breast cancer cells.

These mice are being used to evaluate potential treatments for metastatic breast cancer, as a quick test of whether an individual breast tumour is likely to metastasise, and to compare gene expression in metastatic and indolent breast tumours.

Seth and his co-workers discovered that insulin-like growth factor binding protein 7 (IGFBP7) was down-regulated only in metastatic breast tumours.

Other speakers, including Warren Thomas from Beaumont Hospital, Dublin, Ireland, discussed the clinical application of studies of signal transduction in cancer.

Thomas gave an interesting talk about mesothelioma, an aggressive tumour that is linked to asbestos exposure and that is expected to peak in incidence in the UK and Ireland in the 2020s as the exposed population ages.

He presented survey results that showed that females with this condition have, on average, a longer survival time after diagnosis than males.

This suggested a link between this cancer and oestrogen signalling, and Thomas found that high levels of one oestrogen receptor beta isoform, ERβ2 – which cannot bind oestrogen – were correlated with good median survival.

High levels of the steroid receptor co-activator SRC-2 and of p16 were also associated with a relatively good prognosis in these patients.

Further presentations covered personalised therapies for lung cancer and an association between the BRAFV600E mutation in colorectal cancer, right-sided tumour presentation and anaemia.