As cancer researchers around the world struggle to find more effective treatments for malignant pleural mesothelioma, a team of Japanese doctors has published an editorial on two drugs they call “possible new therapeutic agents” for the asbestos cancer.
The agents are both drugs that have been in the spotlight for a while and have been tested as mesothelioma treatments with promising results. The authors, who are with Hyogo College of Medicine in Hyogo, Japan, summarized recent findings on the two drugs in a new issue of Expert Review of Anticancer Therapy.
Potential Mesothelioma Treatment 1: Anti-CD26 Monoclonal Antibody
The first agent mentioned in the editorial is a monoclonal antibody known as YS110 that targets the protein CD26. CD26 is a valuable target for mesothelioma treatment because it is overexpressed by mesothelioma cells but not by normal mesothelial cells.
CD26 is believed to play a role in mesothelioma tumor growth and invasion and in the process of cell death known as apoptosis. It is overexpressed in 85 percent of malignant mesothelioma cases.
When cancer researchers at Keio University in Tokyo exposed two different kinds of mesothelioma cells to YS110 in the lab, it slowed down the proliferation of one type by 20 percent in just 2 days. After equally promising tests in mice, the drug entered a Phase 1 trial that included 22 mesothelioma patients.
“YS110 exhibited a favorable safety profile and had signs of clinical activity in heavily pretreated CD26-positive malignant pleural mesothelioma patients who previously showed disease progression while receiving conventional standard chemotherapies,” observe authors Takashi Nakano, Kozo Kuribayashi, and Koji Mikami.
YS110 is now the subject of a Phase II trial to determine the best dose for mesothelioma treatment.
Potential Mesothelioma Treatment 2: Naftopidil and its Analog
The second drug highlighted in the editorial is a blood pressure medication called naftopidil and it’s chemically similar analogue, HUHS1015.
Naftopidil, which is marketed under the brand name Flivas in the US, is an alpha blocker or alpha-adrenergic antagonist. There is increasing evidence that it may have antitumor properties in a variety of cancer types, including mesothelioma.
In addition, recent research on the naftopidil analog HUHS1015 found that it reduced cell viability in malignant mesothelioma cells and suppressed tumor growth in mice.
“These preliminary encouraging results suggest that naftopidil and its analogue HUHS1015 can be developed as effective anticancer drugs for the treatment of malignant pleural mesothelioma,” write the study authors.
Mesothelioma is an aggressive malignancy that starts on the membranes that surround internal organs. Although mesothelioma can take decades to develop, once it progresses to the point that it begins to cause symptoms like chest pain and coughing, the prognosis is usually very poor. It is highly resistant to conventional cancer treatments.
Takashi, N et al, “Possible new therapeutic agents for malignant pleural mesothelioma: anti-CD26 monoclonal antibody and naftopidil”, October 8, 2016, Expert Review of Anticancer Therapy