Expression of G6PD: Prognostic Marker for Merkel Cell Carcinoma?
Posted: Monday, March 1, 2021
Akimichi Morita, MD, PhD, of Nagoya City University Graduate School of Medical Sciences, Japan, and colleagues suggested that expression of the glucose-6-phosphate dehydrogenase (G6PD) gene may be a helpful marker for predicting immunotherapy responses in patients with Merkel cell carcinoma. The results, published in the Journal for ImmunoTherapy of Cancer, indicated that G6PD expression was an accurate detector through both blood serum tests and immunohistochemical staining. By contrast, previously reported prognostic markers, such as Merkel cell polyomavirus infection or PD-L1 expression, remain insufficient for predicting variable patient outcomes.
“The relationship between G6PD and immune activity in Merkel cell carcinoma opens up a new therapeutic concept for all malignancies,” the research team concluded.
The researchers collected 90 specimens from 71 patients and 53 blood serum samples from 21 patients with Merkel cell carcinoma. Samples were analyzed using next-generation sequencing, immunohistochemical staining, and blood serum tests.
Next-generation sequencing classified the tissue samples into two types: “immune active” and “cell division.” The immune active type was associated with improved clinical outcomes versus the cell division type. Also, a significantly upregulated level of expression of G6PD was observed in the cell division type samples. Furthermore, G6PD gene expression was significantly correlated with lymph node or distant metastasis during the disease course and negatively correlated with PD-L1 expression.
Compared with PD-L1 expression as a prognostic marker, immunohistochemical staining of G6PD exhibited less heterogeneity in results. G6PD activity was also accurately reflected using blood serum tests—the detection values significantly increased with cancer progression and significantly decreased after treatment.
Disclosure: For full disclosures of the study authors, visit jitc.bmj.com.