Mitf-KO Mouse

Mitf, also known as microphthalmia-associated transcription factor, is a basic helix-loop-helix leucine zipper (bHLH-LZ) transcription factor. It is an important regulator of melanogenesis, melanocyte development, and survival. It plays a role in multiple biological processes such as melanin synthesis, local proliferation, and inhibition of invasion, inflammation, and epithelial-to-mesenchymal (EMT) transition in normal melanocytes [1]. MITF is also a lineage-survival oncogene involved in melanoma development [2].

In uveal melanoma (UM), mitfa deficiency in zebrafish models (a form of loss-of-function experiment) was found to accelerate UM tumor onset and progression. This indicates that MITF acts as a tumor suppressor in UM, which is in contrast to its essential role in cutaneous melanoma (CM) development and maintenance [4]. In melanoma, MITF promotes proliferation, suppresses senescence, and anticorrelates with immune infiltration and therapy resistance [3].

In conclusion, Mitf is crucial for melanocyte-related biological functions including development, pigmentation, and survival. Model-based research, especially the zebrafish model with mitfa deficiency, has revealed its distinct roles in different types of melanoma. These findings contribute to understanding the mechanisms of melanoma development and may provide potential targets for melanoma treatment.

References:

1. Gelmi, Maria Chiara, Houtzagers, Laurien E, Strub, Thomas, Krossa, Imène, Jager, Martine J. 2022. MITF in Normal Melanocytes, Cutaneous and Uveal Melanoma: A Delicate Balance. In International journal of molecular sciences, 23, . doi:10.3390/ijms23116001. https://pubmed.ncbi.nlm.nih.gov/35682684/

2. Louphrasitthiphol, Pakavarin, Loffreda, Alessia, Pogenberg, Vivian, Mazza, Davide, Goding, Colin R. 2023. Acetylation reprograms MITF target selectivity and residence time. In Nature communications, 14, 6051. doi:10.1038/s41467-023-41793-7. https://pubmed.ncbi.nlm.nih.gov/37770430/

3. Chauhan, Jagat S, Hölzel, Michael, Lambert, Jean-Philippe, Buffa, Francesca M, Goding, Colin R. 2022. The MITF regulatory network in melanoma. In Pigment cell & melanoma research, 35, 517-533. doi:10.1111/pcmr.13053. https://pubmed.ncbi.nlm.nih.gov/35771179/

4. Phelps, Grace B, Hagen, Hannah R, Amsterdam, Adam, Lees, Jacqueline A. 2022. MITF deficiency accelerates GNAQ-driven uveal melanoma. In Proceedings of the National Academy of Sciences of the United States of America, 119, e2107006119. doi:10.1073/pnas.2107006119. https://pubmed.ncbi.nlm.nih.gov/35512098/