Disease relevance of KLK5

• We have previously shown that KLK5 is differentially expressed in ovarian and breast cancer [1].
• CONCLUSIONS: KLK5 should be further studied as a potential new prognostic marker in prostate cancer, whose expression is negatively correlated with cancer aggressiveness [1].
• Differential splicing of KLK5 and KLK7 in epithelial ovarian cancer produces novel variants with potential as cancer biomarkers [2].
• KLK5 and KLK7, two members of the human tissue kallikrein family, are differentially expressed in lung cancer [3].
• KLK5 expression is significantly more expressed in squamous cell carcinoma than in matched nonmalignant lung tissue (P=0.02), whereas expression of KLK7 was decreased in adenocarcinoma (P=0.003) [3].

High impact information on KLK5

• KLK5 was shown to be differentially expressed at the mRNA level in breast and ovarian cancer [4].
• 4. Human kallikrein (hK) gene 5 (KLK5) is a member of this family and encodes for a secreted serine protease (hK5) [4].
• Two members of the human tissue kallikrein (KLK) family of (chymo)tryptic-like serine proteases, KLK5 and KLK7, are implicated in desquamation by digestion of (corneo)desmosomes and inhibition by desquamation-related serine protease inhibitors (SPIs) [5].
• The new kallikrein-like gene, KLK-L2. Molecular characterization, mapping, tissue expression, and hormonal regulation [6].
• KLK-L2 is up-regulated by estrogens and progestins in the breast cancer cell line BT-474 [6].

Chemical compound and disease context of KLK5

• Like the genes that encode PSA and other kallikreins, the KLK5 gene was found to be regulated by steroid hormones in the BT-474 breast cancer cell line [7].
• Previous investigations have established that the expression of KLK5 is estrogen and progestin driven in the BT-474 breast cancer cell line [8].

Biological context of KLK5

• Down-regulation of the human kallikrein gene 5 (KLK5) in prostate cancer tissues [1].
• Since we had noted that not all trypsin-like activity in the plantar stratum corneum could be ascribed to KLK5, we set out to identify other skin proteases with similar primary substrate specificity [9].
• Altogether, our results suggest that variability in KLK5 and KLK7 gene expression might be involved in lung tumorigenesis and useful for clinical purposes [3].
• Kallikrein gene 5 (KLK5, also known as KLK-L2), located on chromosome 19q13.4, is one of the newly identified members of the kallikrein gene family, which is a subgroup of the serine protease enzyme family [10].
• KLK5-SV2 has 7 exons, the first 2 of which are untranslated, and 6 intervening introns [11].

Anatomical context of KLK5

• We also found that one novel KLK5 transcript with a short 5'-untranslated region and a novel KLK7 transcript with a long 3'-untranslated region were highly expressed in the ovarian cancer cell lines OVCAR-3 and PEO1, respectively, but were expressed at very low levels in normal ovarian epithelial cells [2].
• LEKTI is localized in lamellar granules, separated from KLK5 and KLK7, and is secreted in the extracellular spaces of the superficial stratum granulosum [12].
• In normal human tissues, KLK5 is highly expressed in skin, mammary gland and testis [10].
• KLK5-SV2 is expressed in a variety of tissues, with higher expression levels in the mammary gland, cervix, salivary gland and trachea [11].
• 4. Although it is expressed at low levels in various tissues, KLK5 expression is highest in the human mammary gland and testis [8].

Associations of KLK5 with chemical compounds

• Ovarian tissues were then classified as KLK5 positive or negative, based on ethidium bromide staining of the PCR product on agarose gels [10].

Regulatory relationships of KLK5

• Moreover, our results suggest that SCTE is able to activate the proform of SCCE [13].

Other interactions of KLK5

• In normal skin, LEKTI, KLK7, and KLK5 were all found in the lamellar granule (LG) system, but were separately localized [12].
• RESULTS: High KLK5 expression was found more frequently in pre-/perimenopausal (P = 0.026), node-positive (P = 0.029), and estrogen receptor-negative (P = 0.038) patients [7].
• Utilizing Expressed Sequence Tag database analysis and reverse transcriptase polymerase chain reaction, we identified a new alternatively spliced form of KLK5(KLK5-splice variant 2, KLK5-SV2) [11].

Analytical, diagnostic and therapeutic context of KLK5

• METHODS: We compared the expression of KLK5 in 29 pairs of histologically confirmed normal and prostate cancer tissues by quantitative RT-PCR using the LightCycler technology [1].
• Human kallikrein gene 5 (KLK5) expression by quantitative PCR: an independent indicator of poor prognosis in breast cancer [7].
• Antibodies against bacterial recombinant stratum corneum tryptic enzyme were produced and purified by affinity chromatography [14].

References