Inside our cells, strands of DNA wrap around spool-like histone proteins to form a DNA-histone complex called chromatin. Bradley Bernstein, a pathologist at Massachusetts General Hospital, Harvard University, and Broad Institute, has always been fascinated by this process. What interests him is the fact that an approximately 6-foot-long strand of DNA can be folded and packed into orderly chromatin structures inside a cell nucleus that’s just 0.0002 inch wide.
Bernstein’s fascination with DNA packaging led to the recent major discovery that, when chromatin misfolds in brain cells, it can activate a gene associated with the cancer glioma . This suggested a new cancer-causing mechanism that does not require specific DNA mutations. Now, with a 2016 NIH Director’s Pioneer Award, Bernstein is taking a closer look at how misfolded and unstable chromatin can drive tumor formation, and what that means for treating cancer.
Caption: My wife Diane inspired me and my staff to volunteer to make dinner for patients and their families at The Children’s Inn at NIH. Credit: NIH Record
My blog usually celebrates biomedical advances made possible by NIH-supported research. But every August, I like to try something different and highlight an aspect of the scientific world that might not make headlines. This year, I’d like to take a moment to pay tribute to just a few of the many NIH family members around the country who, without pay or fanfare, freely give of themselves to make a difference in their communities.
I’d like to start by recognizing my wife Diane Baker, a genetic counselor who has always found time during her busy career to volunteer. When I was first being considered as NIH director, we had lots of kitchen table discussions about what it might mean for us as a couple. We decided to approach the position as a partnership. Diane immediately embraced the NIH community and, true to her giving spirit, now contributes to some wonderful charities that lend a welcome hand to patients and their loved ones who come to the NIH Clinical Center here in Bethesda, MD.
Caption: Oncologists review a close-up image of a brain tumor (green dot). Credit: National Cancer Institute
Scientists have spent much time and energy mapping the many DNA misspellings that can transform healthy cells into cancerous ones. But recently it has become increasingly clear that changes to the DNA sequence itself are not the only culprits. Cancer can also be driven by epigenetic changes to DNA—modifications to chemical marks on the genome don’t alter the sequence of the DNA molecule, but act to influence gene activity. A prime example of this can been seen in glioblastoma, a rare and deadly form of brain cancer that strikes about 12,000 Americans each year.
In fact, an NIH-funded research team recently published in Nature Communications the most complete portrait to date of the epigenetic patterns characteristic of the glioblastoma genome . Among their findings were patterns associated with how long patients survived after the cancer was detected. While far more research is needed, the findings highlight the potential of epigenetic information to help doctors devise more precise ways of diagnosing, treating, and perhaps even preventing glioblastoma and many other forms of cancer.
Caption: Remembering a few of the many children who’ve died of DIPG; Left, Lyla Nsouli and parents; upper right, Andrew Smith and mom; lower right, Alexis Agin and parents. Credits: Nsouli, Smith, and Agin families
Every year in the United States, several hundred children and their families receive a devastating diagnosis: diffuse intrinsic pontine glioma (DIPG). Sadly, this inoperable tumor of the brain stem, little known by the public, is almost always fatal, and efforts to develop life-saving treatments have been hampered by a lack of molecular data to identify agents that might specifically target DIPG. In fact, more than 200 clinical trials of potential drugs have been conducted in DIPG patients without any success.
Now, using cell lines and mouse models created with tumor tissue donated by 16 DIPG patients, an international research coalition has gained a deeper understanding of this childhood brain cancer at the molecular level. These new preclinical tools have also opened the door to identifying more precise targets for DIPG therapy, including the exciting possibility of using a drug already approved for another type of cancer.