A joint study between UC Berkeley and Columbia University researchers demonstrated that an enzyme in cancer cells is a key part of the tumor-spreading process in human pancreatic cancer.
The study, published June 24, notes that the enzyme methionine sulfoxide reductase A, or MSRA, suppresses the spread of the most common pancreatic cancer in humans. However, researchers found that MSRA occurs less in pancreatic tumors that have already spread across the body.
A decline in MSRA in primary tumors allows another enzyme to increase migration of cancer cells and promote metastasis.
“We discovered a new target in cancer,” said Chris Chang, campus 1942 chair professor of the department of chemistry, in an email. “Loss of this protein in pancreatic cancer leaves these damaging oxygen marks on the proteome, like permanent ink, where they lead to reprogramming of the cancer’s metabolism to grow and metastasis.”
The study was conducted primarily through various experiments on specially bred mice, which can strongly mirror human physiology.
While the study did find that MSRA injection into primary tumors does not reduce their growth, it did demonstrate that a specially prepared MSRA injection through the spleen greatly reduced the spread of pancreatic cancer to the liver.
“Metastasis, where primary cancers seed and spread to other areas of the body, leads to poor patient prognosis,” Chang said in the email. “Identifying ways that cancers metastasize can help inform new diagnostics and treatments.”
Chang said these results are a culmination of a three-year effort in a multidisciplinary collaboration between various STEM fields at UC Berkeley and in animal biology and clinical samples at Columbia University. It was led by postdoctoral researcher Dan He, a member of Chang’s lab.
The study notes that these observations are particularly significant because they show a clear link between oxygen-based biology and cancer — a connection that is well-known but not understood in detail. Chang said in an email that his research group analyzed how the oxygen humans breathe affects several aspects of people’s health in order to define a “redox code” to study how adding or removing oxygen atoms on cellular proteins affects their behavior.
“We hope to expand this work to inform new companion diagnostics to profile patients to identify those with susceptibility for metastasis in their cancer tumors as well as new drug platforms that can target these oxygen-dependent vulnerabilities,” Chang said in the email.