University of Technology Sydney

An international research team has discovered a new way to effectively treat cancer, by using nutrients to reactivate suppressed metabolic pathways in cancer cells. An international research team has discovered a new way to effectively treat cancer, by using nutrients to reactivate suppressed metabolic pathways in cancer cells. The researchers used a common amino acid, tyrosine, packaged as a nanomedicine, to change the metabolism of melanoma, a deadly skin cancer, and prevent cancer growth. Australia has the highest rate of skin cancer in the world. This new approach could be combined with current therapies to better treat melanoma. The technique also has the potential to treat other types of cancer. The study, Nutrient-delivery and metabolism reactivation therapy for melanoma, was led by Professor Wenbo Bu from Fudan University and Professor Dayong Jin from the University of Technology Sydney, and recently published in the journal Nature Nanotechnology. Tyrosine has limited bioavailability in living organisms. However, the researchers used a new nanotechnology technique to package it into tiny particles called nanomicelles, which are attracted to cancer cell membranes, and break down easily, boosting absorption. The research team then tested the innovative treatment in mice and in human-derived melanoma cells in the lab and found that the tyrosine nanomicelles reactivated dormant metabolic pathways, triggered melanin synthesis, and inhibited tumour growth. "Uncontrolled rapid growth is a key feature that distinguishes cancer cells from normal cells. In cancer cells some metabolic pathways are over-activated, and others are suppressed, to create the environment necessary for rapid spread," said Professor Jin. "While a few metabolism-based drugs for cancer have been developed previously, such as aromatase inhibitors impeding estrogen synthesis in breast cancer and HK2 inhibitors targeting glycolysis in various cancers, these work by suppressing over-activate metabolic pathways," he said. "Our research shows for the first time that cancer can be stopped by reactivating metabolic pathways that are dormant. And this can be done using simple nutrients, such as amino acids, sugars, and vitamins, which are safe, readily available and well tolerated," said Professor Bu. Different types of cancer will respond to different nutrients. Melanoma cells develop from melanocytes -- skin cells that produce melanin. Tyrosine is needed to produce melanin and it can stimulate melanin production, hence its effectiveness with melanoma. The reactivation of melanin synthesis forces the melanoma cell to reduce glycolysis, the process of converting sugar to energy, which is believed to be the mechanism for its anti-cancer effect. Melanoma cells are also susceptible to heat stress. The researchers found that by combining tyrosine nanomicelle treatment with near-infrared laser treatment, they were able to eradicate melanoma in mice after six days and it did not reoccur during the study period. The findings suggest a promising a new frontier in the use of nanomedicine for cancer therapy.

With recent studies having established the presence of nano and microplastic particles in the respiratory systems of both human and bird populations, new research has modeled what happens when people breathe in different kinds of plastic particles and where they end up. With recent studies having established the presence of nano and microplastic particles in the respiratory systems of both human and bird populations, a new University of Technology Sydney (UTS) study has modelled what happens when people breathe in different kinds of plastic particles and where they end up. Led by Senior Lecturer of Mechanical Engineering Dr Suvash Saha, the UTS research team has used computational fluid-particle dynamics (CFPD) to study the transfer and deposition of particles of different sizes and shapes depending on the rate of breathing. The results of the modelling, published in the journal Environmental Advances, have pinpointed hotspots in the human respiratory system where plastic particles can accumulate, from the nasal cavity and larynx and into the lungs. Dr Saha said evidence was mounting on the significant impact of nano and microplastics on respiratory health and the UTS study would provide essential insights for the development of targeted strategies to mitigate potential risks and ensure effective health interventions. "Experimental evidence has strongly suggested that these plastic particles amplify human susceptibility to a spectrum of lung disorders, including chronic obstructive pulmonary disease, fibrosis, dyspnea (shortness of breath), asthma, and the formation of what are called frosted glass nodules," Dr Saha said. "Plastic particle air pollution is now pervasive and inhalation ranks as the second most likely pathway for human exposure. "The primary types are intentionally manufactured, including a wide array of cosmetics and personal care products such as toothpaste. "The secondary ones are fragments derived from the degradation of larger plastic products, such as water bottles, food containers and clothes. "Extensive investigations have identified synthetic textiles as a principal source of indoor airborne plastic particles, while the outdoor environment presents a multitude of sources encompassing contaminated aerosols from the ocean to particles originating from wastewater treatment." Dr Saha said the UTS team's modelling found that breathing rate along with particle size and shape determined where in the respiratory system plastic particles would be deposited. "Faster breathing rates led to heightened deposition in the upper respiratory tract, particularly for larger microplastics, whereas slower breathing facilitated deeper penetration and deposition of smaller nanoplastic particles," he said. "Particle shape was another factor, with non-spherical microplastic particles showing a propensity for deeper lung penetration compared to spherical microplastics and nanoplastics, potentially leading to different health outcomes. "These findings highlight the imperative consideration of breathing rates and particle sizes in health risk assessments associated with respiratory exposure to nano and microplastic particles."

Air conditioning doesn't just cool the air -- it can also reduce the risk of harm from wildfire smoke, new research suggests. Air conditioning in our workplaces and homes doesn't just cool the air -- it can also help trap particles from wildfire smoke and reduce our exposure to potentially harmful elements like soluble mercury, sulfate and nitrate, new research shows. Wildfire smoke can cause or exacerbate health conditions such as asthma, chronic obstructive pulmonary disease (COPD) and heart disease, and lead to an increased risk of hospitalisation and death. The study, recently published in the journal Environmental Pollution, was led by University of Technology Sydney (UTS) PhD candidate in environmental science Raissa Gill, a recipient of a UTS Research Excellence Scholarship, together with researchers from UTS and UNSW Sydney. "The wildfires that raged across Australia during the 2019-2020 'Black Summer' produced an enormous amount of air pollution, with plumes of smoke travelling long distances and cloaking Sydney and surrounding areas," said Gill. "We wanted to find out more about what was in the wildfire smoke we were breathing. By using commercial air conditioning filters, we were able to capture and analyse the chemical composition of particles that would otherwise have been inhaled," she said. The researchers collected particulate matter from heating, ventilation, and air-conditioning (HVAC) filters in UTS Buildings 4 and 7 during the peak of the Black Summer wildfires as well as one year later as a reference point. They found daily particulate matter concentrations were generally 2-3 times higher than normal, with hourly concentrations reaching up to 10.5 times the usual maximum. This exceeded the national standards on 19% of days across the four-month sampling window. The particles were also finer and contained a different mixture of toxic chemicals. "Wildfire aerosols contained much smaller, rounder particles than urban aerosols, making them more likely to be inhaled into our lungs and to transfer toxic elements into our blood stream," said co-author UTS Professor Martina Doblin. "These particles also contained more soluble forms of mercury, as well as higher concentrations of sulfate, nitrate and fluoride ions and metals including manganese, cobalt, and antimony. Mercury is quite toxic even in low concentrations and can cause neurological problems and lung damage." The study highlights the diverse chemical changes that severe wildfire events exert on the atmosphere. Understanding these changes is crucial for assessing the impact of wildfires and their potential consequences for human health and environmental quality. "While air quality in Sydney is usually good by world standards, recent evidence has clearly shown that the handful of days that we get every year with high pollution loads from wildfires and dust storms lead to significant disease and death in the community," said co-author UTS Associate Professor Fraser Torpy. "Studies that build an understanding of these high pollution events are critical in helping us determine what is causing these health crises, and will lead towards a better understanding of how we can protect the vulnerable members of the community that suffer from them," he said. While HVAC systems are not designed specifically for wildfire smoke, research on indoor air quality in Canberra during the 2019-2020 fires showed that outdoor concentrations of fine particulate matter were up to 10 times higher than measured values indoors with air conditioning. The current study shows the UTS HVAC filters were able to capture a significant portion of wildfire smoke, reducing exposure to toxic particles for staff and students working in these buildings. It also underscores the importance of considering higher-rated HVAC filters during fire seasons and maintaining and replacing the filters regularly. "Australians face significant obstacles in achieving satisfactory air quality during major wildfire events. Many homes and older buildings rely on natural ventilation or have poor HVAC filtration efficiency and gaps that allow smoke to enter. These systems can also be costly and complicated to manage for effective protection during wildfires," Gill said. "Given that severe wildfires are projected to increase with climate change, the role of wildfire-ready infrastructure in maintaining public health, as well as the need to reduce greenhouse gas emissions, is now more pressing than ever."