TITLE:
Embryonic-like stem cells derived from postpartum placenta delivered after spotaneous labor emerging as universal prophylactic cancer vaccine
AUTHORS:
Manole Corocleanu
KEYWORDS:
Placenta; Embryonic-Like Stem Cells; Preventive Cancer Vaccine
JOURNAL NAME:
Stem Cell Discovery,
Vol.3 No.4,
October
30,
2013
ABSTRACT:
In the eighth decade of
the last century extensive clinical delayed-type hypersensitivity (DTH) skin
tests to an intradermal injection of a pharmaceutical allogeneic human Placenta
Suspension (phPS) performed in obstetrical, gynecological and control group
patients have shown positive reaction in 239 patients with clinical conditions
having been as histopatrhological substratum, a hypoxia-induced
adaptive/reactive epithelial cell proliferation, e.g. syncytiotrophoblastic
cell hyperplasia, endometrial cell hyperplasia, or different gynecological cancers. Because the immune response
against phPS has shown antigenc similarities between normal placental and endometrial hyperplastic cells and different kinds of cancer cells and because many cancers adopt an embryonic stem-like
gene expression pattern, it is suggested that the profile of hypoxia-promoting
placental and endometrial stem cell proliferation is more embryonic-like, and
that the immune respose against phPS is expected to cross-react with tumor
cells in vivo. In the process of persistent
growth and accelerated oxygen consumption
by hyperplastic cytotrophoblastic
cells and neoplastic cells in a hypoxic microenvironment, a basic shift
in energy metabolism is accompanied by appearance of heat shock proteins (HSPs), of fetal isoenzymes and of membrane
glycoproteins (reappearance of oncofetal
antigens, OFAs), which, as result of their overexpression/amplification
may induce a host immunological response. Thus, it is assumed that phPS
prepared from full-term human placentas delivered after a spontaneous labor
comprises stem/progenitor cells reverted to a proliferative embryonic stem
cell-like-state upon exposure to labor-inducing intrmittent placental hypoxia and that by expressing
HSP/OFAs could immunize to generate immune response againjst a variety of
antigens that are shared by different kinds of epithelial cancers. This
immunological feature of phPS qualifies is as a vaccine-related product that
may be used for a preventive cancer vaccine when mixed with a potent adjuvant
(BCG-Vaccine) and given normal healthy individuals.