An article published in Molecular Cancer Research by scientists at North Dakota State University, reveals potential mechanism of severe pain in pancreatic cancer. It seems that substance P ( SP), a neurotransmitter involved in pain development, has an important role in pancreatic cancer, and may be one possible target for cancer treatment.
The mechanism by which pain occurs in pancreatic cancer is not clear. One possible explanation lies in nerve invasion by pancreatic tumor. Therefore, the researchers wanted to find what is the underlying mechanism of perineural invasion on pancreatic cancer and the mechanism by which substance P induces pain in this type of cancer. Substance P is a neuropeptide that functions as a neurotransmitter and is secreted by cells of the central nervous system but also by APUD system cells (Amine Precursor Uptake and Decarboxylation), which are found in the gastrointestinal tract.
It seems that substance P is distributed not only in the nervous system, but also in pancreatic cells. In addition, researchers have found that NK-1R is overexpressed in pancreatic cancer cells. Studies conducted so far revealed that NK-1R antagonists inhibits the effects of substance P, which causes tumor growth and dissemination in the body. In addition, it appears that substance P is involved in neurite outgrowth and dissemination of pancreatic cancer cells in the posterior nerve roots.
Erxi Wu, assistant professor of pharmaceutical sciences, co-author of the paper, said that the study shows that substance P plays an important role in dissemination of pancreatic cancer and perineural invasion, and that blocking NK-1R signaling system, so the effects of substance P, may be a possible strategy for pancreatic cancer treatment.
In pancreatic cancer, one of the major symptoms is pain, besides general manifestations such as weight loss, fatigue, anorexia, etc.. Because it is sometimes severe, pain is the main symptom that sends the patient to the doctor. One mechanism of pain is nerve invasion by the tumor, so the occurrence of pain means that the cancer is large enough in size so that it compresses nerves.
It should be noted that pancreatic cancer behaves differently depending on location (pancreas is composed of head, body and tail). A tumor that occurs in the head of the pancreas has early symptoms: jaundice, itching, discolored feces, urine highly colored, diffuse pain etc. A tumor in the pancreatic body and tail has fewer symptoms: severe abdominal pain and, sometimes, splenomegaly.
Major treatment of pancreatic cancer is surgical (Whipple operation, for example) and is indicated for both tumor resection and digestive complications treatment. Besides surgery, radiotherapy and chemotherapy can prolong survival of patients with pancreatic cancer.