Direct,
intracrine conversion of 25(OH) D to calcitriol by T cells.
10) The human ocular tissues are among the target tissues equipped for
intracrine synthesis and metabolism of oestrogens and androgens.
7,9,10) These observations suggest that adrenal and
intracrine contributions to the tumour androgen signaling axis represent important targets for further hormonal modulation of prostate cancer.
For example, the differentiation of endothelial cells and cancer cells is regulated by VEGF through an
intracrine mechanism (Carmeliet et al.
The single
intracrine FGF subfamily is the FGF11/12/13/14 subfamily.
Since the vascular epithelium is considered a metabolically active organ, possessing endocrine, paracrine, autocrine and
intracrine functions, (119) optimizing these functions can assist in optimizing blood pressure.
Actually a hormone, with endocrine, paracrine as well as
intracrine activity, Vitamin D is involved in both type 1 and type 2 diabetes mellitus development.
1,2,4) A second enzyme, CYP27B1, is found in over 30 cell types and acts to further metabolize 25(OH) D to form the locally produced
intracrine 1,25[(OH).
Indeed after menopause nearly 100% estrogens are formed in peripheral tissues and exert their effects locally in a paracrine or
intracrine manner.
It has become clear that angiogenic factors produced by leukemic blasts may also act in an autocrine or
intracrine fashion, thereby stimulating cell proliferation and survival through a mechanism independent from angiogenesis (6).
DHEA has indirect endocrine and
intracrine actions due to conversion to androgens and estrogens.
77,81-83) Thus, it has been proposed that local expression of POMC peptides and their corresponding receptors may alter melanoma behavior through autocrine,
intracrine, or paracrine mechanisms and/or through the modulation of the local immune and vascular systems.
