A pair of cancer researchers from Rome say treatment for malignant pleural mesothelioma could be improved if more clinicians considered the newest prognostic tools in their treatment planning.
Pleural mesothelioma is a malignancy of the membranes that encase the lungs. It is caused by exposure to the mineral asbestos and is highly resistant to conventional cancer therapies. Many mesothelioma patients do not survive longer than 12 months from the onset of their symptoms. But Tommaso Mineo, MD, and Vincenzo Ambrogi, PhD, of the Department of Experimental Medicine and Surgery at Policlinico Tor Vergata University say newly discovered biomarkers and other tumor factors could lead to more tailored treatment and, potentially, better outcomes.
“Therapy is currently guided by gross tumor characteristics and patient features; however, these seem less accurate than the biological fingerprint of the tumor,” they write in a recent issue of Oncology. The two go on to summarize the new and existing factors that could help doctors better select patients for targeted therapies.
The first category of prognostic indicators they discuss are genetic factors. These include chromosomal alternations, DNA methylation (implying a downregulation of individual genes), microRNA expression and gene mutations. Several studies have also found that mesothelioma patients tend to exhibit a deregulation of gene expression.
Another category of prognostic indicators, according to the mesothelioma study, are molecular pathway factors. According to the authors, these involve various cell mechanisms, including growth factors, cell-cycle regulators, apoptosis (pre-programmed cell death) and angiogenesis (formation of new blood vessels). Oxidative stress, as indicated by high cyclooxygenase-2 (COX-2) expression and the overexpression of certain growth factors such as epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) fall under this category. Molecular pathways also include other signaling pathways, some newly-discovered, that either impede normal cell death in mesothelioma cells or help them grow by speeding up angiogenesis.
“These all might be of help in formulating an early diagnosis as well as in selecting a more accurately targeted treatment,” conclude the authors. Because mesothelioma is so difficult to treat, most cases require a multimodal approach. Drs. Mineo and Ambrogi contend that “an adequate knowledge and evaluation of prognostic factors can help in defining the multidisciplinary approach to therapy in order to reduce the mortality from this lethal disease.”