Detection of keratinocyte growth factor (KGF) messenger ribonucleic acid and immunolocalization of KGF in the canine testis

Trade‐offs between male fertility reduction and selected growth factors or the klotho response in a lipopolysaccharide-dependent mouse model

The increasing number of depression cases leads to a greater need for new antidepressant treatment development. It is postulated that antidepressants may harm male fertility, but the cellular mechanism is still poorly understood. The role of growth factors and klotho protein in maintaining normal male reproductive function is well documented. Hence, the study aimed to investigate the effect of the antidepressant drug – imipramine (tricyclic AD), and other substances with antidepressant potential (ALS), administered in combination or in combination with LPS (an animal model of depression) on gene expression and protein synthesis of IGF-2 (insulin-like growth factor 2), TGF-β1 (transforming growth factor β1), NGF (nerve growth factor), KGF (keratinocyte growth factor) and protein synthesis of VEGF-A (vascular endothelial growth factor A), IGF-IR (insulin-like growth factor receptor 1), EGFR (epidermal growth factor receptor) and klotho in the testis of mice. Mice were injected intraperitoneally with selected ALS and LPS or 10% DMSO (controls) (n = 7/group) once a day for 14 days. Animals were decapitated and testes collected for RNA and protein purification. PCR and western blot methods were employed for the evaluation of growth factors and klotho expression. The results obtained indicated a decreased level of most of the analyzed genes and proteins, except KGF; its expression increased after treatment with MTEP and IMI administrated individually and after NS-398, and IMI in combination with LPS. Our results may suggest that the tested ALS and LPS can contribute to a reduction of male fertility, but NS-398, IMI, and IMI+NS-398 may also act as stimulants after LPS.

Immunolocalization of the keratinocyte growth factor in benign and neoplastic human prostate and its relation to androgen receptor

BACKGROUND

Growth and development of the prostate are androgen-dependent. Keratinocyte growth factor (KGF), widely expressed by mesenchymal cells, is thought to act like an andromedin between stroma and epithelium of the prostate. Since KGF has recently emerged as an autocrine mediator in prostate cancer, we investigated the role KGF plays in the human prostate and its relationship to androgen receptor (AR).

METHODS

Normal (n = 13), benign hyperplastic (n = 5), and neoplastic (n = 14) human prostate tissues as well as cultured epithelial and stromal cells were analyzed using polymerase chain reaction (PCR), Western blot analysis, and immunohistochemistry.

RESULTS

Reverse transcriptase polymerase chain reaction and Western blotting showed KGF expression in stromal cultured cells of the normal prostate but not in epithelial cells. Using immunohistochemistry, KGF was found to be localized in fibroblasts and smooth muscle cells, independent of prostate disease. There was KGF expression in epithelial cells of BPH and prostate cancer. Human androgen receptor was uniformly expressed in the same secretory glandular cells that were positive for KGF in BPH and prostate cancer.

CONCLUSIONS

Our results provide evidence that KGF is a stromal-derived mediator, recently shown to act in a paracrine manner in normal prostate but now detected in epithelial cells in prostate cancer and BPH. These findings support the hypothesis that KGF might act as an autocrine factor in prostate cancer and BPH.

Parathyroid hormone-related protein is a positive regulator of keratinocyte growth factor expression by normal dermal fibroblasts

Parathyroid hormone-related protein (PTHrP), an important factor in the pathogenesis of humoral hypercalcemia of malignancy, is produced by many normal tissues, including the skin, where it regulates keratinocyte growth and differentiation and dermal fibroblast function. Keratinocyte growth factor (KGF), a member of the fibroblast growth factor (FGF) family, is a secretory product of stromal cells and functions as a mediator of epithelial cell growth and differentiation. Phenotypes of the skin in several transgenic mouse models, in which the KGF and PTHrP genes have been overexpressed or disrupted, suggest that these two factors interact in vivo to regulate homeostasis of the skin. In this study, we investigated the effects of KGF on PTHrP secretion and expression by normal human foreskin keratinocytes (NHFK) and the effects of PTHrP on KGF secretion and expression by normal human dermal fibroblasts (NHDF) in vitro. N-terminal PTHrP(1-36) increased KGF secretion, protein expression and mRNA expression by NHDF in a dose-dependent manner, however, KGF did not regulate PTHrP expression and secretion by NHFK. By flow cytometry, PTHrP also increased the percentage of NHDF producing KGF. Our results indicate that PTHrP produced by keratinocytes is a potential paracrine regulator of KGF expression by dermal fibroblasts in vivo. This paracrine regulation may explain, in part, the epidermal atrophy seen in the PTHrP null mice and epidermal hyperplasia seen in transgenic mice overexpressing PTHrP in their basal keratinocytes. Our results also suggest that PTHrP is an important mediator for the healing of skin wounds and growth of neoplasms of squamous origin.