Table I.

Summary of studies that have evaluated progesterone receptor expression and localisation in endometriotic lesions.

Reference	Sample	Phenotype	Findings
Bedaiwy et al., 2015	C, E, L	SUP, OMA	PRA (Western blot): C < E > OMA > SUP PRB (Western blot): C = E > OMA > SUP
Beliard et al., 2004	E, L	SUP	PRA + PRB (immunohistochemistry): C = E > L Down-regulation in the secretory phase in C and E, but not in L
Bono et al., 2014	L	OMA	PRA + PRB (immunohistochemistry): detected in 10/10 samples PRB (immunohistochemistry): detected in 6/10 samples
Eaton et al., 2013	C, L (stromal cells)	OMA	PRA (western blot): C > L PRB (western blot): C > L
Hayashi et al., 2012	C, L	OMA	PRA (immunohistochemistry): C = L PRB (immunohistochemistry): C > L
Wu et al., 2006	C, E, L	SUP, OMA	PRB mRNA (real-time PCR): C > E > L Hypermethylation or PGR at the PRB promoter region in L
Attia et al., 2000	E, L	‘extra-ovarian’	PRA (western blot): E > L PRB (western blot): only E
Beranič and Rižner, 2012	L (Z-12 cell line)	SUP	Expressed PRB mRNA (real time PCR) and protein (western blot)
Vinci et al., 2016	L	DIE	PRA + PRB (immunohistochemistry): detected in 34/112 samples
Zanatta et al., 2015	L	DIE	PRA + PRB (immunohistochemistry): detected in 17/18 samples PRB (immunohistochemistry): detected in 17/18 samples
Liu et al., 2018	C, L	OMA, DIE	PRB (Immunohistochemistry): C>DIE>OMA

C: control endometrium from healthy women; E: eutopic endometrium from women with endometriosis; L: endometriotic lesion; SUP: superficial peritoneal endometriosis; OMA: ovarian endometrioma; DIE: deep infiltrating endometriosis; PRA: progesterone receptor A; PRB: progesterone receptor B; PGR: progesterone receptor gene