Steroid hormones regulate cell proliferation, survival and
development and have been involved in the origin and/or progression of cancer.
In the last decades, many epidemiological and experimental studies have
suggested that steroid hormones may be etiologic factors in tumor generation,
but whereas for some tumors, the link
between hormones and cancer is well established, in other cases the
relationship is not fully defined or even contradictory.
Many human cancers, especially those of reproductive
tissues, depend on progesterone. PG is known to participate in the regulation
of several physiological and pathological processes in mammals, such as ovarian
function, growth and differentiation of the uterine endometrium and mammary
gland. However, PG also participates in non-reproductive processes, such as
neural excitability, learning and memory, and in pathological processes like
cancer. In literature, however, data exploring the relationship between progesterone
and cancer are controversial. One of the main problems lies in the fact that
depending on the cell type, hormonal environment, growth conditions, and
developmental stage, progesterone can either stimulate or inhibit cell
proliferation or promote cell differentiation. It has been reported that the
lifetime exposure to reproductive hormones, in particular progesterone and/or
estrogens, affects the risk of breast cancer and melanoma.
Melanoma is a widespread skin cancer with very poor
prognosis. It is an old story, however still debated, that the outcome of
established melanoma is influenced by endocrine status although the acquisition
of melanoma does not seem to be influenced by female sex hormones. Early
studies showed that female patients with malignant melanoma had some survival
advantage, which in some studies was observed in preas opposed to
post-menopausal women.
No comments:
Post a Comment