Single Review on past events

Cancer is a major public health problem and the second leading cause of death. This is one of the reasons why chemist Marilena Manea is interested in developing a cancer chemotherapeutic approach that targets the tumors with peptides. How this works she explained in her Jour Fixe talk. The most common treatments of cancer are surgery, radiation therapy and chemotherapy. However, in the case of advanced or metastatic cancer, chemotherapy is still the main therapeutic approach. Mainly due to their lack of selectivity, the administration of free chemotherapeutic agents (i.e., conventional chemotherapy) is followed by side effects like a decreased production of blood cells, immunosuppression, inflammation of the lining of the digestive tract, hair loss etc. Therefore, the development of an alternative targeted chemotherapeutic method, providing increased selectivity and decreased systemic toxicity, is of interest for Marilena Manea and represents one of her research topics.

What is the main difference compared to the conventional method? In case of the targeted chemotherapy, the anticancer drug is attached to a so-called targeting moiety, for instance a peptide, which will specifically bind to its receptors expressed on the surface of cancer cells. Thus, the hybrid cytotoxic compound (i.e., anticancer drug-peptide bioconjugate) will enter the cancer cells by a receptor mediated way.  It has been found that several regulatory peptides have membrane-bound receptors on different types of tumors.  One of these peptides – that the chemist uses in her work – is the Gonadotropin-releasing hormone (GnRH). GnRH receptors are highly expressed on cancer cells, with limited expression in healthy tissues; hence, they are important molecular targets for cancer therapy. GnRH derivatives are employed as targeting moieties for the attachment and subsequent delivery of anticancer drugs to tumors expressing GnRH receptors. In her work, Marilena Manea employs modified GnRH peptides to reach the best results in targeting the tumors and reducing the side effects of chemotherapeutic agents. But that´s what makes her research also highly difficult and surely will take her yet some more years to find a targeted chemotherapeutic agent that could be applied on humans.

Marilena Manea´s talk was also her farewell, as her 5-year Fellowship at the Zukunftskolleg ended. But she will stay at the University of Konstanz working on a transitional position in the Department of Chemistry.