A series of studies have revealed that there is a genetic link between schizophrenia and cancer.
Schizophrenia is a biological condition that affects a person's ability to think clearly, distinguish reality from fantasy, to manage emotions, make decisions and relate to others.
The studies, led by Dr. Daniel Weinberger of National Institute for Mental Health (NIMH), and American College of Neuropsychopharmacology (ACNP) member, provide a possible scientific explanation for lower rates of cancer among patients with schizophrenia, despite having poor diets and high rates of smoking, and their parents.
Researchers emphasised that many of the genes associated with schizophrenia were the same as the genes associated with cancer, but that the cells that had these genes used them in opposite ways in the two disorders.
While cancer results from changes in the genes that cause cells to go into metabolic overdrive and multiply rapidly, those same genes cause cells in schizophrenia to slow to a crawl.
"We found that many of the same genes are involved in schizophrenia as in cancer, but in a yin and yang way. This will provide critical insight into the molecular structure of schizophrenia," said Weinberger.
Some of the genes showing this yin-yang effect include NRG1, AKT1, PIK3, COMT, PRODH and ErbB4. While these genes can't be used to predict exactly who will develop these diseases, Weinberger said that they could be used to help determine risk.
Dr. Amanda Law of the University of Oxford, who heads one of the teams working at the NIMH, explored specific genetic pathways that cells use to make basic decisions about their development and their fate.
"This is about basic decision making by cells—whether to multiply, move or change their basic architecture," said Law.
"Cancer and schizophrenia may be strange bedfellows that have similarities at the molecular level. The differences lie in how cells respond to external stimuli: in cancer the molecular system functions to speed up the cell and in schizophrenia the system is altered in such a way that causes the cell to slow down," Law added.
She said that selective targeting of these pathways might be a potential target in developing treatments for schizophrenia.
"It's very curious that a brain disorder associated with very complicated human behaviour has at a genetic and cellular level a striking overlap with cancer, a very non-behaviour related disorder. Understanding these pathways might provide us with some new strategies for thinking about cancer," said Weinberger.
Weinberger said that future research involves using this information to search for therapeutic insights that can reverse these processes, with implications not only for treatment of schizophrenia, but also maybe for cancer as well.