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Archive - Apr 18, 2018

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To Starve Pancreatic Tumors, Researchers Seek to Block Autophagy & Other Fuel Sources

To get the extra energy they need to fuel their uncontrolled growth, cancer cells break down some of their own parts for fuel - a process known as autophagy, or "self-eating." Researchers from the University of North Carolina (UNC) Lineberger Comprehensive Cancer Center found a possible therapeutic strategy to block self-eating in one of the deadliest cancers, as well as to cut off the tumor's other energy sources. The researchers are reporting preclinical findings for a potential two-treatment strategy to block multiple mechanisms of cancer cell metabolism in pancreatic cancer at the American Association for Cancer Research (AACR) Annual Meeting in Chicago. The findings were presented on April 18, 2018. "We know that cancer cells have a greater need for energy than normal cells," said UNC Lineberger's Channing Der (photo), PhD, Sarah Graham Kenan Distinguished Professor in the UNC School of Medicine Department of Pharmacology. "They get their energy by changing normal metabolic processes to allow them to generate more energy, and one of these processes is self-eating. Basically what a cancer cell does is it does this more efficiently than a normal cell." In other studies, pancreatic cancer cells have been known to rely more heavily on autophagy, but UNC Lineberger scientists reported evidence that a type of treatment -- an ERK inhibitor -- actually increased their reliance on this. The researchers believe the compound prevents the cell from relying on other energy sources, driving it toward autophagy. "The cancer cell has many ways to achieve what it wants in terms of getting more energy," Dr. Der said. "We find that if you try to stop one, a cancer cell has the ability to compensate. I think the analogy many of us use is the 'whack-a-mole' concept where you knock one thing down, and something else pops up.

University of Pennsylvania Continues Advancements in Cancer Immunotherapy with New Perspective

(by Rachel DeRita, PhD Candidate,Thomas Jefferson University, Department of Cancer Biology). The Abramson Cancer Center at the University of Pennsylvania (UPenn) continues to make innovative advancements in the field of cancer immunotherapy in the midst of what has been called the “immune revolution” by the cancer center’s director, Robert H. Vonderheide (photo), MD, PhD. He explains that the success with the revolutionary immune system-based therapies is “bittersweet,” as many patients are either non-responsive or re-lapse after initial success. A main strategy of the current cancer immunotherapies is to block the immune system’s “off switch.” For example, when the molecule PD-1 on immune cells is bound to PD-L1 on tumor cells, the immune system deactivates and allows the cancer to hide from the immune system. Antibodies against PD-1 (pembrolizumab, brand name Keytruda) can block the deactivation caused by PD-1/PD-L1 binding, and are approved for the first-line treatment of metastatic non-small cell lung cancer with overexpression of PD-L1. Approximately 30% of patients to not respond to this treatment and another 25% exhibit further tumor progression after one year. The search for improvements to current immunotherapies has led to a new class of immunotherapy drugs known as monoclonal antibodies to a protein called CD40. CD40 is expressed by the antigen-presenting cells of the immune system, which are responsible for eliciting an anti-tumor response. When CD40 is bound by other surface markers on T-helper cells, the antigen-presenting cell (such as a B cells or dendritic cells) is activated to perform a number of functions to eventually target and kill tumor cells. By stimulating this molecule with an antibody, the anti-tumor response is strengthened. Dr.

Moss Capable of Removing Arsenic from Water Discovered in Northern Sweden

A moss capable of removing arsenic from contaminated water has been discovered by researchers from Stockholm University. And it happens quickly - in just one hour, the arsenic level is so low that the water is no longer harmful for people to drink. The study has been published in the in the June 2018 issue of Environmental Pollution. The article is titled “Phytofiltration of Arsenic by Aquatic Moss (Warnstorfia fluitans). The aquatic moss Warnstofia fluitans, which grows in northern Sweden, has the ability to quickly absorb and adsorb arsenic from water. The discovery allows for an environmentally friendly way to purify water of arsenic. One possible scenario is to grow the moss in streams and other watercourses with high levels of arsenic. In the northern part of Sweden, water from mining areas is often contaminated by arsenic. "We hope that the plant-based wetland system that we are developing will solve the arsenic problem in Sweden's northern mining areas," says Dr. Maria Greger, Associate Professor at the Department of Ecology, Environment and Plant Sciences at Stockholm University and leader of the research group. "Our experiments show that the moss has a very high capacity to remove arsenic. It takes no more than an hour to remove 80 per cent of the arsenic from a container of water. By then, the water has reached such a low level of arsenic that it is no longer harmful to people," says research assistant Arifin Sandhi, who has conducted the experiments. In 2004, the use of arsenic compounds in wood products was banned, but arsenic still reaches ground and water systems due to mining. This happens because the ground and bedrock in certain parts of Sweden naturally contain arsenic. As a result, the drinking water and water used for the irrigation of crops also contains elevated levels of arsenic.