A common spice frequently used in Asian cooking may hold the key to hindering the advancement of mesothelioma, a type of cancer found in the lining of the lung.
Scientists from Case Western Reserve University, Cleveland, Ohio, and the Georg-Speyer-Haus, Frankfurt, Germany, have shown that applying curcumin – derived from the spice turmeric – in the presence of cancer-inhibiting peptides can boost the strength of a cancer-slowing protein inhibitor. It is hoped the study’s findings can lead scientists a step closer to understanding how patients can become cancer free.
Understanding the value of curcumin for cancer patients
Curcumin is an antioxidant and an active ingredient in turmeric. Antioxidants are compounds frequently found in plants and known to protect the body’s cells from the onslaught of activated molecules – known as free radicals – that are believed to cause a variety of diseases and disorders.
According to the American Cancer Society, benefits of turmeric can be illustrated by the fact that curcumin has demonstrated some anti-cancer effects in the lab by interfering with several significant molecular pathways believed to be involved in cancer presence, growth, and spread. Research results have shown curcumin inhibited the formation of cancer-causing enzymes in rodents, according to the American Cancer Society, which added that curcumin can kill and slow the growth of cancer cells in vitro.
It has also been shown to reduce cancer growth and shrink tumors of lab animals.
Why is curcumin so effective at preventing cancer cell growth?
A 2011 study looked at the benefits of turmeric by taking advantage of the fact that curcumin stays in the intestine rather than absorbing into the bloodstream, leading researchers to investigate whether it might reduce the number of cancer precursors in the rectum and colon.
They found that smokers who consumed 4 grams of curcumin a day had fewer abnormal crypt foci following the study than smokers who took only 2 grams a day, who showed no change. Research continues on whether curcumin can actually reduce the prevalence of colon and rectum cancers – leaving patients cancer free.
Science is looking at ways to slow down the progression of cancer
In the most recent study, Onio and German investigators analyzed tissue samples of mesothelioma tumors from patients at three geographical locations across the United States, comparing patient mortality and the specific type of mesothelioma suffered.
While mesothelioma has been linked to asbestos exposure, many of the 43,000 people killed worldwide by this cancer on an annual basis have never been exposed to asbestos. While widespread, treatment options have remained limited, with less-than-optimal results.
Senior research author Afshin Dowlati, MD, Professor of Medicine – Hematology/Oncology, Case Western Reserve University School of Medicine, was quoted in a statement by the University confirming that better ways to treat mesothelioma are necessary.
“We now understand the mechanisms that drive cell proliferation and growth in malignant mesothelioma,” said Dowlati, a member of the Case Comprehensive Cancer Center, referring to the study’s findings.
It is believed that many cancers, mesothelioma included, are triggered by the action of an intraceullular protein and transcription factor known as STAT3. STAT stands for “signal transducer and activator of transcription.” A signal transducer and activator acts as a pathway for instructing growth and survival of cells throughout the body. The term “transcription factor” refers to a protein that controls genetic information that tells cells how to perform.
Cancer is linked to the presence of STAT3 because the transcription factor has a reputation for providing misdirection that sparks the onset of human cancers and then fuels their continued growth. However, the protein inhibitor known as PIAS3, which stands for “protein inhibitor of activated STAT3,” has the ability to slow, and even block, the ability of STAT3 to spur cancer growth.
Has science discovered the true ‘anticancer’ power of curcumin?
Investigators were able to link levels of PIAS3 with STAT3 activity in each tissue sample. In addition, the researchers assessed the impact of curcumin and peptides extracted from PIAS3 on malignant mesothelioma cells in vitro.
Curcumin and PIAS3 peptides raised PIAS3 levels in the study, which inhibited the cancer-causing activity of STAT3, even killing off mesothelioma cells. These latest findings are believed to provide proof that these two compounds are effective in treating malignant mesothelioma. The research is characterized as representing the first steps toward an actual clinical trial for treatment.
A potential treatment strategy for cancer patients is on the horizon
The medical community has long observed that mesothelioma does not progress consistently in patients even when stages, grades and clinical presentation of the tumor are very comparable. This suggests that the presence of PIAS3 in patients could serve as a marker because its expression was found to have a positive impact on patient survival, based on the study’s findings.
The results have led investigators to suggest that PIAS3 activation could be a therapeutic strategy for mesothelioma patients. “Mesothelioma patients who have low PIAS3 and high STAT3 have a greater chance of dying early,” explained Dowlati. “On the flip side, those patients with high PIAS3 levels have a 44 percent decreased chance of dying in one year, which is substantial.”
The scientists believe these findings may lead to further investigation of what role PIAS3 could hold in inhibiting other cancers that are caused by STAT3 action.