Correlative studies have already provided evidence that five other protein members of KLK family (KLK4, KLK5, KLK7, KLK8
, and KLK10) were abundantly expressed in head and neck squamous cell carcinoma, showing diagnostic value .
Kallikrein-related peptidase-8 (KLK8
) is an active serine protease in human epidermis and sweat and is involved In a skin barrier proteolytic cascade.
We have examined the prognostic value of alternative mRNA variants of the KLK8  (kallikrein-related peptidase 8) gene.
KLK8 was originally cloned from a human skin library (9) as a homolog of a gene encoding mouse neuropsin.
To analyze KLK8 gene expression, we based the design and synthesis of primer sets on the published mRNA sequence of KLK8-T1 (set KLK8, GenBank accession no.
KLK8 was highly abundant in the esophagus, skin (adult and fetal), and tonsil, with lower concentrations in the adrenal gland (adult and fetal), breast, kidney (adult and fetal), fetal liver, salivary gland, and vagina.
The highest concentrations of KLK8 were found in breast milk and CVF.
We confirmed KLK8 presence in the ovary, esophagus, kidney, salivary gland, skin, tonsil, breast, and cervix, as reported (28).
(30) found no overexpression of the 15 tissue kallikreins in breast cancer tissue compared with healthy breast tissue and down-regulation of the expression of at least 4 tissue kallikrein genes (KLK5, KLK6, KLK8
, and KLK10) in breast cancer tissue.
[According to the official kallikrein gene nomenclature, KLK8 is the gene and hK8 is the protein (8).] Originally, KLK8 was cloned from a human skin cDNA library as a homolog of mouse neuropsin (9).
The 887-base fragment containing the full-length KLK8 cDNA was cut with EcoRI restriction enzyme from the KLK8/pGEM-T Easy plasmid (9) and ligated into the EcoRI sites of the pVL1393 transfer vector (PharMingen) to create plasmid KLK8/pVL1393.
The cells were then infected with 100 [micro]L of stock baculovirus solution containing full-length KLK8 cDNA (1.3 x [10.sup.8]-pfu/mL) and cultured at 27 [degrees]C for 4 days.