Shining light on a malignant lung cancer
Treating a rare type of malignant lung cancer could improve, thanks to near-infrared irradiation and a cancer-targeting compound. Nagoya University oncologist Kazuhide Sato and colleagues tested the treatment and published their findings in the journal Cells.
Malignant pleural mesothelioma (MPM) is a rare type of cancer that affects the lung lining. It rarely spreads to other parts of the body, but is usually diagnosed too late, leading to a poor prognosis and very limited treatment options.
“The lungs and chest cavity contain a large amount of air and are thus very good at effectively transmitting near-infrared light,” says Sato. “NIR-PIT is a safe phototherapy option that can target a region of interest. The antibody-IR700 conjugate is also non-toxic to the body in the absence of near-infrared light irradiation. We thus thought that NIR-PIT could be an effective strategy for controlling localized MPM.”
The team’s research showed that podoplanin was widely expressed in a variety of MPM cell lines. They found that NZ-1 conjugates well with the photoabsorber IR700 and that NZ-1-IR700 specifically bound to podoplanin on cells in the lab. When podoplanin-positive cells, including MPM cancer cells, were mixed with NZ-1-IR700 and then irradiated with near-infrared light, the cells immediately swelled and ruptured.
Sato and his colleagues say further studies are needed to find ways that ensure the treatment will not kill healthy podoplanin-positive cells. The researchers also suggest a more focused dose of light could be achieved by shining it into a drainage device inserted into the chest cavity, which is normally used anyway in MPM patients to drain the chest from excess fluids.