Table 3.

DR agonist/antagonists.

Subtype	Drug	Material basis	Model	Effect	Mechanism	References
DR agonists	Fenoldopam	1	MDA-MB-231 cells BALB/c mice	Suppressed cell viability, inhibited invasion, and induced apoptosis in multiple breast cancer cell lines	Inhibited the cGMP/protein kinase G (PKG) pathway	[18]
	l-stepholidine (l-SPD)	2	Pharmacodynamics, PD model	The reduction in the number of lung metastases was approximately proportional to the square of the drug dose	Inhibited the emission rate of tumor cells in situ to inhibit metastasis	[156]
	A77636	3	MDA-MB-231 cells 4T1 cells BALB/c mice	Inhibited the proliferation of breast cancer cells and the bone metastasis of breast cancer mice	The expression of activated T-nuclear factor 1 was downregulated to inhibit the development of osteoclasts, reduce osteolytic lesions, and improve the bone density of the femur and tibia	[92]
	C17	4	4T1 cells BALB/c mice	Inhibited lung metastasis in 4TL in situ mouse model of breast cancer	Upregulated E-cadherin, downregulated Snail and N-cadherin
	Bromocriptine	7	MCF-7 cells	Inhibited cell proliferation	Activated DRD2	[109]
DR antagonist	Thioridazine	5	MDA-MB-231 cells MCF-7 cells BALB/c mice	Promoted cell apoptosis and inhibited tumor growth in mouse models of breast cancer	Upregulated E-cadherin and downregulated β-catenin	[157]
	Sulpiride	6	MCF-7 cells	There was no inhibitory effect of single use, but the inhibitory effect was obvious when combined with dexamethasone	Downregulated MMP2 and upregulated E-cadherin	[82]