Molecular Alterations in Sporadic Primary Hyperparathyroidism

Table 1

Summary of the molecular alterations associated with familial and sporadic parathyroid tumors.

	MEN1 [20, 50–52]	CCND1 [31, 53–55]	HRPT2 [13, 56–58]	RET [48]	CaSR [49, 59–61]
Germline mutations	Inactivating mutations, LOH	—	Inactivating mutations, LOH	Activating mutations	Inactivating mutations
(Familial syndrome)	(MEN1)		(HPT-JT)	(MEN2A)	(NSHPT/FHH)
Benign
Somatic mutations	Inactivating mutations, LOH	Activating Inv (11) (p15; q13)	Inactivating mutations	N	N
Prevalence of somatic alteration	20 to 30%	~5%	2 to 4%	—	—
Protein expression (%)	Downregulation (20 to 40%)	Overexpression (30 to 40%)	Downregulation (ND)	ND	Downregulation (Up to 90%)
Malignant
Somatic mutations	Inactivating	ND	Inactivating mutations, LOH	N	ND
Prevalence of somatic alteration	~13%	ND	70 to 100%	—	—
Protein expression (%)	ND	Overexpression (~90%)	Downregulation/loss of expression; (70 to 100%)	ND	Downregulation (~30%)

N: negative; ND: not determined.