Elevated Levels of SOX10 in Serum from Vitiligo and Melanoma Patients, Analyzed by Proximity Ligation Assay

• Published in: PloS one 2016-04, Vol.11 (4), p.e0154214-e0154214
• Main Authors: Blokzijl, Andries, Chen, Lei E, Gustafsdottir, Sigrun M, Vuu, Jimmy, Ullenhag, Gustav, Kämpe, Olle, Landegren, Ulf, Kamali-Moghaddam, Masood, Hedstrand, Håkan
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Analysis; Assaying; Biological Assay; Biological markers; Biology and Life Sciences; Biomarkers; Biomarkers, Tumor - blood; Biomarkers, Tumor - genetics; Blood donors; Blood serum; Cancer therapies; Case-Control Studies; Cohort Studies; Dermatology; Diagnosis; Early Diagnosis; Female; Humans; Immunology; Inspection; Laboratories; Lymphatic Metastasis; Male; Medical prognosis; Medical research; Medicin och hälsovetenskap; Medicine and Health Sciences; Melanocytes; Melanocytes - metabolism; Melanocytes - pathology; Melanoma; Melanoma - blood; Melanoma - diagnosis; Melanoma - genetics; Melanoma - pathology; Metastases; Metastasis; Middle Aged; Oncology; Pathology; Patients; Proteins; Research and Analysis Methods; S100 Calcium Binding Protein beta Subunit - blood; S100 Calcium Binding Protein beta Subunit - genetics; S100b protein; Science; Sensitivity analysis; Sensitivity and Specificity; Skin; Skin cancer; Skin Neoplasms - blood; Skin Neoplasms - diagnosis; Skin Neoplasms - genetics; Skin Neoplasms - pathology; Sox10 protein; sox10 proximity ligation assay; SOXE Transcription Factors - blood; SOXE Transcription Factors - genetics; Studies; Transcription factors; Treatment Outcome; Tumors; Vitiligo; Vitiligo - blood; Vitiligo - diagnosis; Vitiligo - genetics; Vitiligo - pathology
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0154214

The diagnosis of malignant melanoma currently relies on clinical inspection of the skin surface and on the histopathological status of the excised tumor. The serum marker S100B is used for prognostic estimates at later stages of the disease, but analyses are marred by false positives and inadequate sensitivity in predicting relapsing disorder. To investigate SOX10 as a potential biomarker for melanoma and vitiligo. In this study we have applied proximity ligation assay (PLA) to detect the transcription factor SOX10 as a possible serum marker for melanoma. We studied a cohort of 110 melanoma patients. We further investigated a second cohort of 85 patients with vitiligo, which is a disease that also affects melanocytes. The specificity of the SOX10 assay in serum was high, with only 1% of healthy blood donors being positive. In contrast, elevated serum SOX10 was found with high frequency among vitiligo and melanoma patients. In patients with metastases, lack of SOX10 detection was associated with treatment benefit. In two responding patients, a change from SOX10 positivity to undetectable levels was seen before the response was evident clinically. We show for the first time that SOX10 represents a promising new serum melanoma marker for detection of early stage disease, complementing the established S100B marker. Our findings imply that SOX10 can be used to monitor responses to treatment and to assess if the treatment is of benefit at stages earlier than what is possible radiologically.