Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Chemical Compounds Present in Diet Increase Risk of Colon Cancer

04.04.2005


A team of researchers at the Universitat Autònoma de Barcelona, The Catalan Institute of Oncology and the Higher Council for Scientific Research (CSIC) have published a study indicating that exposure to organochlorine compounds, which we ingest in our diets, increases the risk of suffering colorectal cancer.



The authors have identified two types of compounds, present in the blood of cancer patients, in double the quantity of the non-affected population undergoing the study. In addition, the researchers studied the mechanism that triggers the disease. They have been able to deduce that these compounds cause genetic alterations in genes such as the K-Ras and the p53, which are involved in other cancers such as breast cancer or cancer of the pancreas.

Colorectal cancer is the third most frequent type of cancer in humans and the second deadliest in industrialised countries. Its causes, however, are not fully understood, but diet is believed to play an important role. It is thought that vegetables, fruit and fibre-rich foods protect against it; fats, red meat, as well as excessive consumption of calories, and obesity increase the risk of developing it.


To better understand the causes, a team of researchers led by Victor Moreno, researcher at the Universitat Autònoma de Barcelona and The Catalan Institute of Oncology, in collaboration with the CSIC’s Environmental Chemistry Group, have published the first work that establishes an association between organochlorine compounds and colorectal cancer. The article has been published in the specialised journal, Environmental Health Perspectives.

The researchers measured the concentration of organochlorines in the blood serum of a group of patients at the Bellvitge Hospital. One hundred and thirty-two of the patients had been diagnosed with the disease and 76 others were admitted for other reasons. The analyses identified two specific organochlorines: PCB 28 and PCB 118, which were found at a concentration double that found in the remaining patients. These substances belong to the PCBs or polychlorinated biphenyls. They are toxic compounds coming from industrial processes, which are absorbed into the body through what we eat.

At the same time, the team studied patients affected by colon cancer and two genes implicated in the cancer’s development: the K-Ras oncogene and the P53 tumour suppressing gene. The study of mutations indicated the relationship between exposure to PCBs and the presence of transversion type mutations in both genes. That result reinforces the role of PCBs 18 and 128 as probable causes of the carcinogenic processes in the population studied.

The authors believe that the two compounds’ ability to produce mutations lies in their unique shape. They have a flat conformation similar to that of the dioxins, which allows them to initiate a chain of chemical processes that can end in a carcinogenic process. An example of this would be the bonding of the compounds to the aryl hydrocarbon receptor that due to their shape would set off the activation of cellular enzymes that produce reactive oxygen species. The latter are precisely what cause damage to the DNA thereby initiating the carcinogenic process.

In addition, the researchers studied other variables such as food intake to discover whether other factors were involved in increasing the risk. Nevertheless, the results were negative for all groups of foods and only alcohol was seen to be an important risk factor for the population under study.

According to the authors, further studies will need to be done in the future to confirm the results. Those studies would benefit from the inclusion of additional organochlorines, which were not analysed this time, as well as by the inclusion of other compounds associated with cancer such as dioxins and furans.

Organochlorines and colorectal cancer

The organochlorine compounds come from industrial and agricultural uses and are widespread in the environment. Their use has been limited and safety measures for them tightened in the last few years due to their toxic effects in the body. Some of them such as DDT, which was formerly used as an insecticide, have even been prohibited. In spite of that, the organochlorines are persistent contaminants that remain in the environment for long periods of time due to slow degradation.

Diet constitutes the main route of entrance to the body. Once in the body, the organism has difficulty metabolising them and they usually become stored in the adipose tissue. That means that their half life within the body is on the order of years or even decades.

Organochlorines are excreted from the body by the intestinal route, either by recently ingested compounds or by others released from the adipose tissue. Faeces remain in the large intestine for 1 or 2 days. That amount of time makes possible an exchange of compounds with the epithelium of the large intestine, which does not occur in any other part of the intestinal tract. Those factors enhance the activity of the organochlorines and explains their possible implication in the appearance of colorectal cancer.

Octavi López Coronado | alfa
Further information:
http://www.uab.es/uabdivulga/eng

More articles from Health and Medicine:

nachricht Biofilm discovery suggests new way to prevent dangerous infections
23.05.2017 | University of Texas at Austin

nachricht Another reason to exercise: Burning bone fat -- a key to better bone health
19.05.2017 | University of North Carolina Health Care

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>