Repurposing a transplant drug for bone growth

The transplant immunosuppressant drug FK506, also known as tacrolimus or Prograf, can stimulate bone formation in both cell culture and animal Read more

Beyond the amyloid hypothesis: proteins that indicate cognitive stability

If you’re wondering where Alzheimer’s research might be headed after the latest large-scale failure of a clinical trial based on the “amyloid hypothesis,” check this Read more

Mother's milk is OK, even for the in-between babies

“Stop feeding him milk right away – just to be safe” was not what a new mother wanted to hear. The call came several days after Tamara Caspary gave birth to fraternal twins, a boy and a girl. She and husband David Katz were in the period of wonder and panic, both recovering and figuring out how to care for them. “A nurse called to ask how my son was doing,” says Caspary, a developmental Read more

chemotherapy

Overcoming cisplatin resistance

Despite being studied for decades, the chemotherapy drug cisplatin is revealing new aspects of how it works. Researchers at Winship Cancer Institute of Emory University have identified an enzyme responsible for making tumors and cancer cell lines resistant to cisplatin, along with an experimental drug that targets that enzyme.

The results were published on July 19 in Cancer Cell.

Winship researcher Sumin Kang, PhD

Cisplatin is a DNA-damaging agent used in standard treatment for lung, head and neck, ovarian, and testicular cancers. It has a simple structure, grabbing DNA with its metallic (platinum) arms to form crosslinks. It used to be known as “cis-flatten” because of its nausea-inducing side effects. The experimental drug, lestaurtinib, has already been tested in clinical studies in combination with other chemotherapy drugs, which means it could easily go into trials against tumors displaying cisplatin resistance.

Sumin Kang, PhD, and colleagues at Winship decided to look for enzymes whose activity was necessary for cancer cells to withstand cisplatin treatment. They chose kinases, enzymes that often control some aspect of cell growth and are have plenty of existing drugs targeting them. The researchers found that in combination with a sub-lethal amount of cisplatin, “knocking down” the activity of the kinase MAST1 kills a cell. But how does that combination work?

Read more

Posted on by Quinn Eastman in Cancer Leave a comment

SUMO wrestling enzyme important in DNA repair

The DNA in our cells is constantly being damaged by heat, radiation and other environmental stresses, and the enzyme systems that repair DNA are critical for life. A particularly toxic form of damage is the covalent attachment of a protein to DNA, which can be triggered by radiation or by anticancer drugs.

Keith Wilkinson, PhD

Emory biochemist Keith Wilkinson and colleagues have a paper this week in the journal eLife probing how a yeast protein called Wss1 is involved in repairing DNA-protein crosslinks. The researchers show how Wss1 wrestles with a protein tag called SUMO on the site of the DNA damage, and how Wss1 and SUMO are involved in the cleanup process.

Three interesting things about this paper:

*The paper grew out of first author Maxim Balakirev’s sabbatical with Wilkinson at Emory. Balakirev’s home base is at the CEA (Alternative Energy and Atomic Energy Commission) in Grenoble, France.

* Since many cancer chemotherapy drugs induce protein-DNA cross links, an inhibitor of cross link repair could enhance those drugs’ effectiveness. On the other side of the coin, mutations in a human gene called Spartan, whose sequence looks similar to Wss1’s, cause premature aging and susceptibility to liver cancer. Whether the Spartan-encoded protein has the same biochemical activity as Wss1 is not yet clear.

*SUMO stands for “small ubiquitin-like modifier”. The eLife digest has an elegant explanation of what’s happening: Read more

Posted on by Quinn Eastman in Cancer Leave a comment

Heated, targeted chemotherapy helps abdominal cancers

Cancer of the colon, ovaries, appendix or other organs within the abdomen often spreads to the lining of the abdominal cavity. Experts call this condition peritoneal surface malignancy. Until recently, treatment options for this form of cancer only provided relief from symptoms.

Emory University Hospital is one of a few facilities nationwide to utilize a new combination therapy to slow or prevent recurrence of this cancer. Hyperthermic intraperitoneal chemoperfusion (HIPEC) is a procedure done immediately following surgery that delivers heated chemotherapy directly into the abdominal cavity where it can penetrate cancerous tissue. Heat at 42 C (107 F) destroys cancer cells and enhances the power of chemotherapy.

The term “intraperitoneal” means that the treatment is delivered to the abdominal cavity. “Hyperthermic chemoperfusion” means that the solution containing chemotherapy is heated to a temperature greater than normal body temperature.

Charles Staley, MD, chief of surgical oncology at the Emory Winship Cancer Institute, says by bathing the abdomen with heated chemotherapy immediately following surgery doctors can administer a higher dose of medication than would normally be tolerated by a patient if given intravenously – the traditional way chemotherapy is administered.

During surgery, Staley removes all visible tumors throughout the abdomen, a procedure known as cytoreductive surgery. Following surgery, while still in the operating room, Staley administers the new treatment, which takes about two hours. Recent studies show improved prognosis in patients treated with HIPEC after the cytoreductive surgery.

Illustration of heated chemo therapy

Illustration of heated, targeted chemotherapy

Posted on by Vince Dollard in Uncategorized Leave a comment