Could ALK Phosphorylation Be Linked to Outcomes in Merkel Cell Carcinoma?
Posted: Monday, July 26, 2021
According to research presented in PLOS One, phosphorylation of the oncogene ALK appeared to commonly occur in tumor samples from patients with Merkel cell carcinoma and may be associated with Merkel cell polyomavirus positivity and improved survival. However, phosphorylated ALK was rarely observed in patient cell line samples.
“Since the majority of established [Merkel cell carcinoma] cell lines lack ALK phosphorylation, the next approach would be to study ALK phosphorylation in patient-derived [Merkel cell carcinoma] xenograft models,” noted Virve Koljonen, MD, PhD, of the University of Helsinki, and colleagues. “Ultimately, in vitro drug testing with xenograft models or even in vivo trials could be necessary in order to resolve whether ALK inhibitors would be beneficial in treating [Merkel cell carcinoma].”
The study included tissue microarrays from 136 Merkel cell carcinoma tumor samples from patients who had been diagnosed between 1983 and 2013, as well as 9 Merkel cell carcinoma cell lines. Patient data were collected from the Finnish Cancer Registry and Helsinki University Hospital records. Immunohistochemistry was used to evaluate each microarray and cell line for the presence of ALK and phosphorylated ALK.
A total of 47.8% of the tumor samples were found to have phosphorylated ALK, the presence of which was associated with Merkel cell polyomavirus positivity, lack of metastases at diagnosis, younger age, and improved disease-specific survival outcomes. Of the nine cell lines evaluated, only two were found to have low levels of phosphorylated ALK, whereas five were positive for Merkel cell polyomavirus.
Disclosure: The study authors reported no conflicts of interest.