KRTDAP, or keratinocyte differentiation-associated protein, is involved in the differentiation of keratinocytes. It is part of a cluster of genes related to stratified epithelium secreted peptides complex (SSC), and its expression is coordinated with other epidermal differentiation markers during epidermal morphogenesis [4]. The gene may also play a role in cell adhesion-related pathways as its expression was decreased in cancer stem-like cells isolated from primary oral squamous cell carcinomas [5].

In cancer research, KRTDAP shows potential as a biomarker. It was identified as a hub gene in clinically significant co-expression modules for HPV-negative head and neck squamous cell carcinoma (HNSCC), and along with PSMC2 and ORC5, was found to have high diagnostic value for HPV-negative HNSCC [1]. In oral squamous cell carcinoma (OSCC), its expression was significantly associated with well-differentiated OSCC, and it was among the first-reported genes in OSCC patients [2]. In diffuse malignant epithelioid mesothelioma, KRTDAP expression was higher in low-grade tumours [3]. In melanoma, it was identified as a potential diagnostic and prognostic biomarker [6].

In conclusion, KRTDAP is important in keratinocyte differentiation and may have a role in cell adhesion. Its potential as a biomarker in various cancers, such as HPV-negative HNSCC, OSCC, diffuse malignant epithelioid mesothelioma, and melanoma, makes it a gene of interest in disease diagnosis and prognosis. Although no gene knockout or conditional knockout mouse models were mentioned in the references, the findings from human-based studies suggest its significance in these disease areas.

References:

1. Su, Yushen, Zeng, Zhirui, Rong, Dongyun, Wu, Bei, Cao, Yu. 2021. PSMC2, ORC5 and KRTDAP are specific biomarkers for HPV-negative head and neck squamous cell carcinoma. In Oncology letters, 21, 289. doi:10.3892/ol.2021.12550. https://pubmed.ncbi.nlm.nih.gov/33732365/

2. Kengkarn, Sudaporn, Petmitr, Songsak, Boonyuen, Usa, Poomsawat, Sopee, Sanguansin, Sirima. 2020. Identification of Novel Candidate Biomarkers for Oral Squamous Cell Carcinoma Based on Whole Gene Expression Profiling. In Pathology oncology research : POR, 26, 2315-2325. doi:10.1007/s12253-020-00828-w. https://pubmed.ncbi.nlm.nih.gov/32468250/

3. Forest, Fabien, Laville, David, Habougit, Cyril, Tiffet, Olivier, Péoc'h, Michel. 2021. Histopathological typing in diffuse malignant epithelioid mesothelioma: implication for prognosis and molecular basis. In Pathology, 53, 728-734. doi:10.1016/j.pathol.2021.01.010. https://pubmed.ncbi.nlm.nih.gov/33965253/

4. Bazzi, Hisham, Fantauzzo, Katherine A, Richardson, Gavin D, Jahoda, Colin A B, Christiano, Angela M. . Transcriptional profiling of developing mouse epidermis reveals novel patterns of coordinated gene expression. In Developmental dynamics : an official publication of the American Association of Anatomists, 236, 961-70. doi:. https://pubmed.ncbi.nlm.nih.gov/17330888/

5. Mishra, Amrendra, Sriram, Harshini, Chandarana, Pinal, Ramaswamy, S, Sadasivam, Subhashini. . Decreased expression of cell adhesion genes in cancer stem-like cells isolated from primary oral squamous cell carcinomas. In Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine, 40, 1010428318780859. doi:10.1177/1010428318780859. https://pubmed.ncbi.nlm.nih.gov/29888653/

6. Miñoza, Jose Marie Antonio, Rico, Jonathan Adam, Zamora, Pia Regina Fatima, Dumancas, Gerard G, de Castro, Romulo. 2022. Biomarker Discovery for Meta-Classification of Melanoma Metastatic Progression Using Transfer Learning. In Genes, 13, . doi:10.3390/genes13122303. https://pubmed.ncbi.nlm.nih.gov/36553569/