Thursday, March 31, 2016

Don't Eat At Night: One Way to Reduce Risk of Breast Cancer Recurrence

In patients with breast cancer, a short overnight fast of less than 13 hours was associated with a 36 percent higher risk of breast cancer recurrence, according to research published online  in the Journal of the American Medical Association Oncology.

Ideal, then, would be eating dinner no later than 7 p.m. and breakfast no earlier than 8 p.m. Not the standard American model, is it? This is the second study done on night-time fasting by researchers at the University of California, San Diego School of Medicine.  

Fasting fewer hours per night was associated with significantly less sleep and higher levels of glycated hemoglobin (HbA1c), which is a measure of average blood sugar levels over a period of months. Ellevated HbA1c and poor sleeping habits have been linked to an increased risk of breast cancer. These findings corroborate a paper published in April 2015, in which researchers demonstrated that shorter overnight fasts were associated with worse blood sugar control.

“Previous research has focused on what to eat for cancer prevention, but when we eat may also matter because it appears to affect metabolic health,” said Catherine Marinac, lead author and doctoral candidate at UC San Diego Moores Cancer Center. 

The study included 2,413 non-diabetic breast cancer survivors between the age of 27 and 70 studied between 1995 and 2007, with follow up for breast cancer recurrence and mortality. Participants were 86 percent non-Hispanic white and 55 percent were college educated.

“If future trials confirm that habitual prolonged nightly fasting improves metabolic health, this would be an important discovery in prevention that could reduce the risk of cancers, type 2 diabetes, and cardiovascular disease,” said Ruth Patterson, PhD, senior author and leader of the cancer prevention program at Moores Cancer Center.

Source: News release from University of California, San Diego School of Medicine.

Wednesday, March 16, 2016

Four Distinct Subtypes of TNBC

A study just published in Breast Cancer Research caught my eye because it provided additional perspective on why some TNBC tumors are so much more aggressive than others. Earlier research has shown that there are different forms of TNBC, but the classification in this particular study seemed a little clearer and more straightforward. Plus, the entire publication is easily accessible.

The gist of the recent research is that, as has been obvious for some time, basal-like TNBC tumors are the most likely to be aggressive. But there has been a lot of confusion just about everywhere on whether or not all TNBC tumors are basal-like. They are not, and this study shows how and why, and breaks TNBC into four different subtypes. It also might show why some TNBC tumors react to androgen therapy.

The report is pretty easy to track, so take some time to noodle it. The essential nugget, though, comes in the Results section of the Abstract:

All of the 165 TNBC tumors were classified into four distinct clusters, including an immunomodulatory subtype (IM), a luminal androgen receptor subtype (LAR), a mesenchymal-like subtype (MES) and a basal-like and immune suppressed (BLIS) subtype. The IM subtype had high expressions of immune cell signaling and cytokine signaling genes. The LAR subtype was characterized by androgen receptor signaling. The MES subtype was enriched with growth factor signaling pathways. The BLIS subtype was characterized by down-regulation of immune response genes, activation of cell cycle, and DNA repair. Patients in this subtype experienced worse recurrence-free survival than others (log rank test, P = 0.045). Subtype-specific lncRNAs were identified, and their possible biological functions were predicted using co-expression network analyses.

Read more about triple-negative breast cancer in my book, Surviving Triple-Negative Breast Cancer.  Want more content on this page? Make a donation. Just click the Donate button on the link on the right hand column of the blog.