Research news in brief

Cancer survival worst among the poorest

Disparities in cancer survival based on a person’s socio-economic background are widening in New South Wales, according to a study published in open access journal BMC Public Health. Researchers from the University of South Australia extracted data from the population-based NSW Cancer Registry for cancer cases diagnosed in NSW between 1980 and 2008 (n = 651 245). They found that people living in the least disadvantaged areas had a higher chance of cancer survival compared with people from all other areas, with the most pronounced disparities observed for liver, melanoma, prostate, lung, colon and breast cancers. The study also found that people living in outer regional or remote areas had a slightly increased risk of cancer death compared with people living in major cities, with the highest risk elevations seen for stomach, colon, cervix and prostate cancers. When the researchers looked at the disparities over time, they found that there were significant time variations in relation to socio-economic background. Specifically, disparities appear to be widening over time. According to the researchers, the increased risk of cancer death from living in a deprived area needs urgent attention in order to plan targeted actions to reduce the gap. Collaboration between policymakers, government and health care providers is needed to ensure a comprehensive approach, given disparities are likely to be driven by multiple, complex processes. A policy emphasis on socio-economic disadvantage is required if the widening gap in death from cancer trend is to be reversed.

Carbohydrates may be key to a better malaria vaccine

Researchers from the Walter and Eliza Hall Institute (WEHI) of Medical Research have shown for the first time that carbohydrates on the surface of malaria parasites play a critical role in malaria’s ability to infect mosquito and human hosts. The discovery may lead to improvement in the only vaccine approved to protect people against Plasmodium falciparum malaria – the deadliest form of the disease. Published in Nature Communications, the study showed that the malaria parasite “tags” its proteins with carbohydrates in order to stabilise and transport them, and that this process was crucial to completing the parasite’s lifecycle. The first malaria vaccine for human use – RTS,S/AS01 – was approved by European regulators in July 2015, but has not been as successful as hoped, with marginal efficacy that wanes over time. Dr Ethan Goddard-Borger from WEHI said that the research had attracted much interest because of the implications it has for improving malaria vaccine design. “It was hoped that the vaccine would generate a good antibody response that protected against the parasite; however, it has unfortunately not been as effective at evoking protective immunity as hoped. With this study, we’ve shown that the parasite protein is tagged with carbohydrates, making it slightly different to the vaccine, so the antibodies produced may not be optimal for recognising target parasites,” Dr Goddard-Borger said. He said that there were many documented cases where attaching carbohydrates to a protein improved its efficacy as a vaccine. “It may be that a version of RTS,S with added carbohydrates will perform better than the current vaccine,” he said. “Now that we know how important these carbohydrates are to the parasite, we can be confident that the malaria parasite cannot ‘escape’ vaccination pressure by doing away with its carbohydrates.”

Threatened microbes we shouldn’t ignore

Microorganisms are being moved around the world at an unprecedented scale thanks to human trade, tourism and waste disposal. This is changing global ecosystems and could have big implications for human health — including the spread of diseases — and agriculture, according to researchers from Macquarie University and an international team writing in Science. It could also be driving some bacteria species towards extinction, which is a problem because of the critical role bacteria play in how the planet operates. “The oxygen we breathe is largely made by photosynthetic bacteria in the oceans (and not by rainforests, as is commonly believed),” said Macquarie University biologist Michael Gillings. “Over 95% of the poo in the world comes from humans and the animals we farm. And our poo is travelling around the world with a billion tourists, spreading microbes and antibiotic resistance genes. Until 100 years ago, all the nitrogen in our food came from bacteria we nurtured in our crops. Now more than half comes from artificial fertilisers. And we’re moving trillions of ocean microbes around the world in ballast water. Some one hundred million tonnes of ballast water are dumped in US waters each year. We know they’re introducing foreign starfish, sea snails and seaweed. But we don’t know what invisible changes they’re making to ocean microbes.” The authors called for urgent action to: monitor and model the changes we’re making to the microbial world, and improve waste water and manure treatments to reduce the spread of microbes and resistance genes.

No need to delay using frozen embryos after IVF

Using frozen embryos within a month of their creation improves the chances of having a baby, according to Australian research published in the Australian and New Zealand Journal of Obstetrics and Gynaecology. Frozen embryo transfer (FET) is often delayed after embryos are created to minimise any suspected residual effects from egg stimulation and harvesting. However, until now there were little data to help doctors decide on the right time to implant embryos. The research from Monash University and the University of Melbourne shows that delaying the use of frozen embryos out to 50–70 days had worse pregnancy outcomes than if the embryos are implanted within 25–35 days. The retrospective cohort study, based on a multisite private in vitro fertilisation (IVF) clinic, categorised women into two groups: those having FET cycles administered within 25–35 days or 50–70 days of IVF stimulation cycle and embryo freeze. Outcomes measured were clinical pregnancy and live birth rates. When comparing the patients who had a 25–35 day gap between embryo freeze and FET with the matched patients who had a 50–70 day gap, the statistically significant results showed an adjusted odds ratio for live birth of 1.31 (1.02–1.67). The adjusted odds ratio for clinical pregnancy in matched case control analysis was not statistically significant at 1.22 (0.97–1.53). “A gap of 25–35 days between embryo freeze and FET was associated with improved live birth rates compared to a gap of 50–70 days,” the authors concluded.

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