melan A

melan A

A protein encoded by MART1, which is expressed in melanosomes,  the endoplasmic reticulum and the Golgi apparatus.

Normal expression
Melanocytes of skin and retina.

Abnormal expression
Melanoma (more than 80%), adrenal cortical carcinoma, angiomyolipoma.
References in periodicals archive ?
Tyrosinase, melan A, and KBA62 as markers for the immunohistochemical identification of metastatic amelanotic melanomas on paraffin sections.
In certain cases a Melan A stain was also conducted on selected blocks.
In cases where both stains were done, a pan-nuclear sAC to Melan A ratio was determined.
The average pan-nuclear sAC to Melan A ratio at the margin was 0.
Following our initial assessment of lentigo maligna margins with R21 and Melan A, we felt this immunostain held promise as a tool to both diagnose lentigo maligna and assess surgical margins.
In our study, a relatively high-density pattern of proliferation revealed by Melan A stain could be seen at seemingly negative margins.
In lesions stained by the original protocol, which also highlights sAC expression in keratinocytes, examination of margins can be facilitated by comparison between Melan A and R21 stains.