Table 4.

Protein biomarkers of endometrial receptivity

Study group	Protein	Role	Up-/downregulated, unique in group	References
Proliferative endometrium	Progesterone receptor B, CPM, PALLD, MCM6, ENPP3, PPL, HGD, and PIGR	Cellular growth, proliferation	Up	[107]
Secretory endometrium	PAEP	Inhibition of immune response	Up	[107]
Secretory endometrium	NMDA receptor subunit zeta 1 precursor, FRAT1	Leading to apoptosis, inhibiting subsequent apoptosis	Up	[108]
Proliferative endometrium	Calreticulin precursor, fibrinogen, KAD5, transferrin	Calcium-binding protein, blood-clotting protein, energy metabolism, and blood plasma protein	Up	[109]
Secretory endometrium	ANXA5, PRDX6, AAT, creatine kinase	Apoptosis, antioxidant, protease inhibitor, and energy metabolism.	Up	[109]
Secretory endometrium	ANXA4, KRT8, and HSPB1	Differentiation, apoptosis, inhibition of proliferation, cellular assembly and organization, heat stress	Up	[110]
Secretory endometrium	ALBU	Binding and transportation	Down	[110]
Receptive endometrium	ANXA2	Skeletal development	Up	[111]
Receptive endometrium	STMNI	Cytoskeleton, intracellular signaling cascade	Down	[111]
Receptive endometrium	PGRMCI, ANXA6	Metabolism, rearrangement of cytoskeleton	Down	[112]
Proliferative endometrium	Haptoglobin	Binding of hemoglobin, multi-factorial mechanism protecting the fetus from a maternal allograft-like immune response	Up	[113]
Successful implantation	HSP cognate, HSP, plastin-2, PDIA3, arginase-1, CAPZA-1, ACTBL3, actin, cytoplasmic1, PSMB4, protein deglycase DJ-1, SOD2, CDC42, stathmin, MYDGF, TBCA, GAP-DH, CAPZB, ANXA2	Cell growth, signal transduction, metabolism, cell communication, blood coagulation, barbed-end actin filament capping and regulation of nucleobase, nucleoside, nucleotide and nucleic acid metabolism	Down	[115]
	Catalase, ALBU, serotransferrin, Lg kappa chain V	Transport, metabolism	Up	[115]
Proliferative endometrium	ANT3, A2M	Anti-inflammatory properties, deactivation of MMPs and limits trophoblast invasion	Up	[106]
Secretory endometrium	Haptoglobin precursoranti-TNF a antibody, apolipoprotein A1 fragment, transferrin precursor, vitamin D binding protein variant	Host defense and molecule transport	Up	[117]
	Heat shock protein b1, clusterin precursor, cofilin1, haptoglobin precursor, and other	Apoptosis regulation, cell proliferation, host defense	Down	[117]
Increased in high E2 group	STF, hemopexin, fibrinogen β chain, AACT, C4	Iron transport, acute-phase reaction, blood coagulation, complement activation, programmed cell death, development	Up	[118]
Infertile group	ECM1, TGFB1, SFRP4, CD44	Negative regulation of signaling, cell communication, tissue development	Down	[119]
Infertile group	TGM2, IGHG4	Angiogenesis, wound healing, cell differentiation, immune response	Up	[119]
Fertile group	FLNA, PZP, OVGP1, HSP90B1, ANXA6, RPS3, SEPT2	Cilium assembly, actin filament organization, macromolecule catabolic process	Unique	[119]
Infertile group	AHNAK, ASRGL1, CMPK1, PGM1, CRNN, SBSN	Carbohydrate metabolism, cellular process	Unique	[119]
Pregnant group	LRG isoforms	Infiltration of decidua by uterine natural killer cells	Up	[121]
Receptive endometrium	HMGBI	DNA binding non-histone protein	Down	[120]
No implantation group	PYGB	Glycogenolysis, oxidative stress response	Down	[122]