MART-1/Melan-A and tyrosinase transcripts in peripheral blood of melanoma patients: PCR analyses and follow-up testing in relation to clinical stage and disease progression

Abstract

The use of tyrosinase-based polymerase chain reaction (PCR) tests for the detection of circulating tumour cells in the blood of melanoma patients has led to highly controversial results. We here report on the analysis of 120 blood samples from 76 stage I to IV melanoma patients using a new MART-1/Melan-A PCR system in conjunction with the tyrosinase-specific assay reported in the literature. While there were no positive results in localized disease (stages I and II), identification of specific PCR products in stage III melanoma patients was restricted to the MART-1/Melan-A tests, with positive results in 11% (two out of 19) of the blood specimens analysed. Stage IV melanoma patients presented with the highest incidence of detectable mRNA levels, with positive results for tyrosinase in 38% (12 out of 32) and for MART-1/Melan-A in 22% (seven out of 32). By delineating 64 follow-up specimens covering sampling periods of up to 33 weeks, stable mRNA expression profiles were identified in nearly 95%. Four patients, however, showed PCR changes towards positive MART-1/Melan-A expression that were linked to metastatic melanoma progression. Taken together, PCR tests for tyrosinase and MART-1/Melan-A seem to lack sufficient detection frequencies for the routine monitoring of melanoma disease. Regarding the link between MART-1/Melan-A seroconversion and the development of metastatic disease, further studies are needed to clarify the clinical value of this observation.

Prognostic Value of Multiple Reverse Transcription-PCR Tyrosinase Testing for Circulating Neoplastic Cells in Malignant Melanoma

“…In the majority of published studies, results indicated that TYR-positive patients have a higher risk of recurrence of disease (7, 9 -11, 14, 15, 17, 19 -21 ) and a lower probability of overall survival (8, 11, 18, 20 -24 ). However, other investigators raised doubts concerning the clinical value of monitoring MM progression with use of the TYR test because they found no relationship between positive TYR results and diseasefree and overall survival (13,17,(25)(26)(27)(28).…”

Lack of Prognostic Importance of Reverse-Transcriptase Polymerase Chain Reaction Detection of Circulating Messenger RNA in Patients with Melanoma

“…There have been numerous conflicting reports of the prognostic significance of tyrosinase mRNA. 2,[5][6][7][8][9][10][11][12][13][14][15][16] Our study population showed the expected correlation between disease stage and the outcomes of recurrence and survival, but we observed an unexpected negative correlation between polymerase chain reaction result and time to recurrence. This observation may have been caused by a lack of standardized clinical follow-up in our study.…”

“…This demonstrates the limited clinical value of reverse-transcriptase polymerase chain reaction detection of tyrosinase mRNA in detecting metastatic melanoma and confirms similar findings reported by others. 2,[5][6][7][8][9][10] However, the literature contains a wide range in reported rates of reverse-transcriptase polymerase chain reaction detection of circulating messenger tyrosinase RNA. In a recent meta-analysis by Tsao et al that examined 23 studies, reversetranscriptase polymerase chain reaction for tyrosinase mRNA was positive in 18 percent of patients with stage I disease, 28 percent of patients with stage II disease, 19 percent of patients with stage I/II localized disease, 30 percent of patients with stage III disease, and 45 percent of patients with stage IV disease.…”

“…21 In contrast, Strohal et al concluded that polymerase chain reaction tests for tyrosinase and MART-1/Melan-A lacked sufficient detection frequencies for the monitoring of melanoma disease. 9 Multimarker assays may be associated with an increase in cost and complexity and the higher possibility of falsepositive results. 2 Despite theoretical advantages, multimarker polymerase chain reaction assays do not seem to be consistent/useful at this time.…”

Prognostic role of circulating melanoma cells detected by reverse transcriptase-polymerase chain reaction for tyrosinase mRNA in patients with melanoma

“…RT-PCR for tyrosinase may help identify subgroups of patients at high risk for early relapse for more aggressive adjuvant therapy as different prospective analyses suggest that the PCR result is of prognostic value in melanoma [16][17][18][19][20][21][22][23][24][25]31,33,34,[40][41][42][43][45][46][47][48].…”