Researchers identify enzyme involved in deadly brain tumors

One of the most common types of brain tumors in adults, glioblastoma multiforme, is one of the most devastating. Even with recent advances in surgery, radiation and chemotherapy, the aggressive and invasive tumors become resistant to treatment, and median survival of patients is only about 15 months. In a study published in Neuro-Oncology, researchers at Mayo Clinic identify an important association between the naturally occurring enzyme Kallikrein 6, also known as KLK6, and the malignant tumors.

"Our study of Kallikrein 6 showed that higher levels of this enzyme in the tumor are negatively associated with patient survival, and that the enzyme functions by promoting the survival of tumor cells," says senior author Isobel Scarisbrick, Ph.D., of Mayo Clinic's Department of Physical Medicine and Rehabilitation.

The findings introduce a new avenue for potential treatment of deadly glioblastomas: targeting the function of KLK6. The became more susceptible to treatment when researchers blocked the where the KLK6 enzyme can dock and initiate the survival signal.

Researchers looked at 60 samples of grade IV astrocytomas—also known at this stage as glioblastomas—as well as less aggressive grade III astrocytomas. They found the highest levels of KLK6 were present in the most severe grade IV tumors. Looking at the tumor samples, researchers found higher levels of KLK6 associated with shorter patient survival. Those with the highest levels lived 276 days, and those with lower levels lived 408 days.

"This suggests that the level of KLK6 in the tumor provides a prognosticator of patient survival," Dr. Scarisbrick says.

The group also investigated the mechanism of the enzyme to determine whether it plays a significant role in . Researchers also found glioblastoma cells treated in a with KLK6 become resistant to radiation and treatment.

"Our results show that KLK6 functions like a hormone, activating a signaling cascade within the cell that promotes tumor cell survival," Dr. Scarisbrick says. "The higher the level of the enzyme, the more resistant the tumors are to conventional therapies."

The study is the latest step in Dr. Scarisbrick's investigations of KLK6 in nervous system cells known as astrocytes. arise from astrocytes that have grown out of control. Her lab has shown that KLK6 also plays a role in the perseverance of inflammatory immune cells that occur in multiple sclerosis and in aberrant survival of T-lymphocyte leukemia cell lines.

"Our findings in glioma affirm KLK6 as part of a fundamental physiological mechanism that's relevant to multiple diseases and have important implications for understanding principles of tissue regeneration," she says. "Targeting KLK6 signaling may be a key to the development of treatments for pathologies in which it's necessary to intervene to regulate cell survival and tissue regeneration in a therapeutic fashion. Ultimately, we might be able to harness the power of KLK6 for the repair of damaged organs."

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

Pepper and halt: Spicy chemical may inhibit gut tumors

3 hours ago

Researchers at the University of California, San Diego School of Medicine report that dietary capsaicin – the active ingredient in chili peppers – produces chronic activation of a receptor on cells lining ...

Expressive writing may help breast cancer survivors

4 hours ago

Writing down fears, emotions and the benefits of a cancer diagnosis may improve health outcomes for Asian-American breast cancer survivors, according to a study conducted by a researcher at the University of Houston (UH).

Taking the guesswork out of cancer therapy

10 hours ago

Researchers and doctors at the Institute of Bioengineering and Nanotechnology (IBN), Singapore General Hospital (SGH) and National Cancer Centre Singapore (NCCS) have co-developed the first molecular test ...

Brain tumour cells found circulating in blood

11 hours ago

(Medical Xpress)—German scientists have discovered rogue brain tumour cells in patient blood samples, challenging the idea that this type of cancer doesn't generally spread beyond the brain.

International charge on new radiation treatment for cancer

12 hours ago

(Medical Xpress)—Imagine a targeted radiation therapy for cancer that could pinpoint and blast away tumors more effectively than traditional methods, with fewer side effects and less damage to surrounding tissues and organs.

User comments