'Bouncing' T-Cells could spell new hope for success of mesothelioma treatment
According to a study reported in the British Journal of Cancer
, mesothelioma patients whose T-cell counts bounce back
rapidly after chemotherapy have a better likelihood of surviving
the usually fatal asbestos-related disease.
Researchers were seeking prognostic indicators in mesothelioma patients undergoing chemotherapy. Noting a growing interest in coupling chemotherapy to immunotherapy
, the team also sought a way to decide who would benefit most from the combination.
Chemotherapy is the most common treatment for mesothelioma, an aggressive cancer which attacks the lining, or pleura, of the lungs. It involves flooding the body with a drug or combination of drugs
designed to eliminate cancerous cells.
With immunotherapy, the immune system is 'programmed' to recognise cancer cells as foreign bodies
, attacking them as they would a virus or bacteria.
Researchers wanted to devise a prognostic method for mesothelioma patients
who might undergo both types of therapy. The team looked for longitudinal changes in peripheral T-cell subsets in 40 patients with malignant mesothelioma or advanced non-small cell lung cancer. All subjects were receiving platinum-based chemotherapy.
The study found that the T-cells of all study subjects were almost completely knocked out within 8 days of chemotherapy
. However, most bounced back quickly and even passed baseline levels.
With their immunosuppressive properties, regulatory T-cells (Treg) are responsible for keeping order in the immune system. The study found that Treg cells
were most profoundly depleted by chemotherapy.
Because the effectiveness of immunotherapy depends on the depletion of related Treg cells and the strength of the T-cell pool, the researchers suggested that patients showing the most dramatic changes in these two cell type areas are most likely to benefit from a combined chemotherapy/immunotherapy approach
The researchers concluded that chemotherapy potentially delivers a "favourable environment
" in which to implement immunotherapy in mesothelioma patients, and that T-cell proliferation was likely to be a useful signifier of probable outcomes.