Cytokeratin 15 (CK15), CD10, CD34, and bcl2 have all been evaluated as potential markers for distinguishing trichoepithelioma from BCC, but the utility of these markers largely relies on the ability to interpret particular patterns of staining in the tumor epithelium and/ or surrounding stroma (71(1472),72-76); the authors do not routinely use these markers in their practice (Table 4).
One proposed immunohistochemical algorithm for distinction of MAC, DTE, and morpheaform BCC uses BerEP4, PHLDA1 (pleckstrin homology-like domain, family A, member 1), CK15, and CK19.
Sudden deaths also occurred in 3 broiler chicken flocks (Ck12, Ck15
, Ck21) and 1 duck flock (Dk18); mortality rates were 29%-52% (online Technical Appendix 1 Table 1, https:// wwwnc.cdc.gov/EID/article/24/5/17-1935-Techapp1.pdf).
Most studies have detected negative staining for calponin, CK15
, smooth muscle actin, ER, PR, HER2, and CK5/6 (14).
One of them is cytokeratin 15 (CK15
), which is why CK15+/integrin [alpha]6+ or CD34+/integrin [alpha]6+ cells have been identified as "bulge" cells .
Immuno-histochemical studies have revealed that trichofolliculoma is characterized by activated, aberrant cytokeratin-15 (CK15
)-positive follicle stem cells that show outer root sheath differentiation while attempting to make hair.
All tumours expressed one or more of CK7, CK15
, CK20 and AE1/AE3 and were negative for EBV.
Sections were incubated with primary antibodies, Carcinoembryonic antigen (CEA)/[alpha]-SMA and cytokeratin 15 (CK15
)/[alpha]-SMA at 4[degrees]C overnight.
(86,90) In addition, CK15
stains positive in MAC and is negative in mBCC.
Their recommended panel included p63, D2-40, and CK15
. Positive staining with all 3 favors a PCAN diagnosis, rather than that of metastatic adenocarcinoma (Table 1).
Whereas hypertrophic gene collagen [chi], platelet-derived growth factor [alpha], and reticulocalbin 3 have been identified in chondroid tumors, but not in chordomas, specific cytokeratins such as CK8, CK15
, and CK19; periplakin; CD24; discoidin domain receptor 1; and brachyury are noticeably expressed in chordoma.