If, however, p53 has mutated and become defective, the cancer cells can acquire the ability to evade apoptosis and become more resistant to therapy. Researchers at Karolinska Institutet and Karolinska University Hospital have now obtained results from the first tests using a new substance that can restore the function of defective p53 and activate apoptosis in cancer cells.
The substance is known as APR-246 and has now been tested on humans in a phase I/II study, which was conducted on 22 patients with advanced blood or prostate cancer. Some of the patients came from the Haematology Centre at the Karolinska University Hospital in, Stockholm, where the studys lead investigator, consultant Dr Sören Lehmann is based. The remainder of the patients were from other clinics in Gothenburg, Lund, Uppsala and Örebro.
The patients received daily infusions of APR-246 for four days. When the researchers analyzed the cancer cells taken before and after treatment, they saw indications that the p53 gene had been activated to varying degrees, and that this had triggered the suicide program in the cancer cells. Ten patients could be evaluated as regards the development of their cancer, and in two of them there were signs of tumour regression.
However, the study was actually not designed to test the clinical effects but to ascertain how well the substance was tolerated by the body. With the main adverse reactions confined to temporary tiredness, nausea, headache and confusion, their results would suggest that the substance is well tolerated.
"The side-effects were totally different to those produced by conventional chemotherapy, which bodes well for designing combination therapies," says Dr Lehmann. "And it's in precisely this kind of combination that we think the substance has the greatest potential. In previous laboratory studies we've seen that APR-246 has generated synergy gains when used with chemotherapy due to the mutually enhancing effects of both substances."
Defective p53 is considered one of the most common factors behind the development of cancer. In some cancers, such as ovarian cancer, the vast majority of tumours have defective p53. In total, the p53 tumour suppressor gene is mutated in at least half of all tumours.
"In theory, a drug that restores p53 function should be effective against many different kinds of cancer, provided that the individual tumour contains defective p53," says study team member Professor Klas Wiman. "We should keep in mind, however, that tumours are very complex."
APR-246 was discovered by Klas Wiman and colleagues at Karolinska Institutet, and the present study was led from Karolinska University Hospital in association with Aprea AB. Aprea AB's principal shareholder is Karolinska Development, a company listed on the NASDAQ OMX Stockholm exchange. Professor Wiman is co-founder and shareholder of Aprea, and a member of its board.
Sören Lehmann, Vladimir J.N. Bykov, Dina Ali, Ove Andrén, Honar Cherif, Ulf Tidefelt, Bertil Uggla, Jeffrey Yachnin, Gunnar Juliusson, Ali Moshfegh, Christer Paul, Klas G. Wiman and Per-Ola Andersson
Targeting p53 in vivo: A first-in-man study with the p53-targeting compound APR-246 (PRIMA-1MET) in refractory hematological malignancies and prostate cancerJournal of Clinical Oncology, early online publication 10 September 2012, doi: 10.1200/JCO.2011.40.7783.
Press Office | EurekAlert!
'Y' a protein unicorn might matter in glaucoma
23.10.2017 | Georgia Institute of Technology
Microfluidics probe 'cholesterol' of the oil industry
23.10.2017 | Rice University
Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
23.10.2017 | Event News
17.10.2017 | Event News
10.10.2017 | Event News
23.10.2017 | Life Sciences
23.10.2017 | Physics and Astronomy
23.10.2017 | Health and Medicine