. 2020 Jan 25;21(3):796. doi: 10.3390/ijms21030796

Table 1.

Expression of different connexins and their function in normal and leukemic hematopoiesis.

Cell Type	Connexin Type	Function	Ref.
Normal HSC and BM Stromal Cells
LT-HSC and progenitors	Cx43, Cx45, Cx31, Cx31.1, Cx32, Cx37, and Cx50	Expression	[15,28]
LSK and LK cells	Cx32	Maintain HSPC quiescence and stemness	[29]
HSPC	Cx43	Reduces HSC senescence via ROS transfer to BMSC during stress induced hematopoietic regeneration	[14,15]
BM stromal cells (Osteoblasts, MSC and endothelial cells)	Cx31	Expression	[93]
BM stromal cells (Osteoblasts, MSC and endothelial cells)	Cx43 and Cx45	Regulates CXCL12 secretion, HSC growth, differentiation and homing	[8,17,112,142]
BM stromal cells	Cx43	1) Determine bone mass and bone mineral density by modulating osteogenesis	[16,110,142,182]
		2) Mitochondria transfer from BMSC to HSC and emergency granulopoiesis
		3) HSPC proliferation and differentiation of myeloid blood cell precursor
		4) Hematopoietic regeneration after chemotherapy
BM Endothelial cells	Cx43	Normal vascular function, leukocyte adhesion and transmigration	[9,183]
Leukemia Cell Lines, Primary Cells, and Leukemic BM Stromal Cells
OCIM2 and OCI-AML3 cells	Cx43 and Cx32	↑Cell proliferation	[156]
CCRF-CEM lymphoblast cells	Cx33, Cx40, Cx43, Cx45, Cx46, and Cx50	↑ Chemoresistance	[147]
		↓Apoptosis
		↓Differentiation
HL-60 and PBL-985 cells	GJ	↓Differentiation	[155]
U937 AML cells expressing AML1-ETO fusion protein	Cx43	↓Cell proliferation	[162]
KG-1, KG-1a, HL-60, OCI-AML3, MV4-11, MoLM-13 Jurkat, and THP1 cells	Cx25, Cx31.9, Cx40, Cx43, Cx45, and Cx59	↑Cell proliferation	[161]
	Cx25, Cx31.9, Cx40, Cx43, Cx45, and Cx59	↑Chemoresistance	[161]
Primary AML cells	Cx26, Cx32, Cx37, Cx43, and Cx45	↑ Chemoresistance	[163]
Primary AML cells	Cx26, Cx32, Cx37, Cx43, and Cx45	↓Apoptosis	[163]
AML-blasts and BM CD34⁺ cells	Cx43, Cx45, Cx25, Cx31.9, and Cx59	↑Cell proliferation	[153,163]
AML-blasts and BM CD34⁺ cells	Cx43, Cx45, Cx25, Cx31.9, and Cx59	↑Chemoresistance	[153,163]
AML BM-stromal cells	Cx25, Cx26, Cx30, Cx31, Cx32, Cx36, Cx37, Cx40, Cx46, and Cx62	↑Cell proliferation	[153]
AML BM-stromal cells		↑Chemoresistance	[153]
Primary Multiple Myeloma (MM) cells and cell lines (RPMI 8226, U266, and XG-7)	Cx43	Adhesion and migration of MM cells	[164,165]
		↑Cell proliferation
		↑Chemoresistance
Multiple Myeloma BM-stromal cells	Cx43	Adhesion and migration of MM cells	[164,165]
		↑Cell proliferation
		↑Chemoresistance
Cx32-KO mice		↑Leukemia incidence	[76]