RASSF1A promoter methylation is associated with increased risk of thyroid cancer: a meta-analysis

Figures & data

Figure 1 Flow chart of study selection procedure.

Table 1 Characteristics of eligible studies in the meta-analysis

References (year)	Country	Ethnicity	Histology	Control		Tumor		Methods	Control	QA score
				U (n)	M (n)	U (n)	M (n)
Santoro et al^Citation30 (2013)	Italy	Caucasian	TC	NR	NR	10	9	MSP	NR	NR
Brait et al^Citation31 (2012)	USA	Caucasian	TC	1	13	5	38	QMSP	NT	6
Brait et al^Citation31 (2012)	USA	Caucasian	TC	1	43	5	38	QMSP	BT	6
Qu and Xue^Citation37 (2012)	People’s Republic of China	Asian	TC	21	7	13	15	MSP	AT	8
Dai et al^Citation38 (2011)	People’s Republic of China	Asian	TC	22	10	20	30	MSP	BT	8
Mohammadi et al^Citation32 (2011)	Iran	Caucasian	TC	2	23	6	19	MSP	BT	7
Wang et al^Citation39 (2009)	People’s Republic of China	Asian	TC	10	0	25	63	MSP	NT	6
Lee et al^Citation33 (2008)	Sweden	Caucasian	FTC	16	5	3	18	MSP	NT	7
Nakamura et al^Citation34 (2005)	USA	Caucasian	TC	27	0	51	27	MSP	AT	7
Xing et al^Citation35 (2004)	USA	Caucasian	TC	14	0	32	19	QMSP	NT	7
Xing et al^Citation35 (2004)	USA	Caucasian	TC	14	0	5	4	QMSP	BT	7
Schagdarsurengin et al^Citation36 (2002)	Germany	Caucasian	TC	3	1	11	27	MSP	NT	6

Abbreviations: AT, adjacent tissue; BT, benign tissue; FTC, follicular thyroid carcinoma; M, methylation sample; MSP, methylation-specific PCR; NR, not reported; NT, normal tissue; PCR, polymerase chain reaction; QA, quality assessment; QMSP, quantitative methylation-specific PCR; TC, thyroid carcinoma; U, unmethylation sample.

Figure 2 Forest plot for the association between Ras-associated domain family 1A promoter methylation and risk of thyroid cancer.

Abbreviations: CI, confidence interval; OR, odds ratio.

Figure 3 Forest plot for the association between Ras-associated domain family 1A promoter methylation and risk of follicular thyroid carcinoma.

Abbreviations: CI, confidence interval; OR, odds ratio.

Figure 4 Forest plot for the association between Ras-associated domain family 1A promoter methylation and risk of papillary thyroid carcinoma.

Abbreviations: CI, confidence interval; OR, odds ratio.

Table 2 Meta-analysis of association between Ras-associated domain family 1A promoter methylation and thyroid cancer risk

Variables	Controls/cases (n)	OR	95% CI	Heterogeneity
				I^2 (%)	P-value
Total	118/347	8.27	4.38–15.62	47.20	0.078
Ethnicity
Caucasian	80/231	9.25	3.97–21.56	46.90	0.110
Asian	38/116	7.01	2.68–18.38	70.30	0.066
Disease type
FTC	104/94	11.88	5.80–24.32	51.50	0.067
PTC	83/166	8.07	3.54–18.41	8.4	0.359
Sample type
Normal tissue	63/241	9.55	4.21–21.67	51.80	0.081
Adjacent tissue	55/106	6.80	2.49–18.56	58.10	0.122
Pathogenesis
Distant metastasis	183/67	1.18	0.64–2.16	34.60	0.191
TNM-stage	64/32	1.79	0.72–4.44	52.60	0.121

Abbreviations: CI, confidence interval; FTC, follicular thyroid carcinoma; OR, odds ratio; PTC, papillary thyroid carcinoma.

Figure 5 Funnel plot of publication biases on the association between Ras-associated domain family 1A promoter methylation and thyroid cancer risk.

Figure 6 Funnel plot of publication biases on the association between Ras-associated domain family 1A promoter methylation and follicular thyroid carcinoma risk.

Figure 7 Funnel plot of publication biases on the association between Ras-associated domain family 1A promoter methylation and papillary thyroid carcinoma risk.

Figure 8 Trial sequential analysis comparing the Ras-associated domain family 1A promoter methylation frequency of control group and thyroid cancer group.

Abbreviation: RIS, required information size.

Table S1 Thyroid cancer risk

References	Country	Ethnicity	Histology	U (n)	M (n)	U (n)	M (n)	Methods	Control type	NOS score
Santoro et al^Citation1	Italy	Caucasian	Thyroid carcinoma	NR	NR	10	9	MSP	NR	NR
Brait et al^Citation2	USA	Caucasian	Thyroid carcinoma	1	13	5	38	QMSP	Normal tissue	6
Brait et al^Citation2	USA	Caucasian	Thyroid carcinoma	1	43	5	38	QMSP	Benign tissue	6
Qu and Xue^Citation3	People’s Republic of China	Asian	Thyroid carcinoma	21	7	13	15	MSP	Adjacent tissue	8
Dai et al^Citation4	People’s Republic of China	Asian	Thyroid carcinoma	22	10	20	30	MSP	Benign tissue	8
Mohammadi^Citation5	Iran	Caucasian	Thyroid carcinoma	2	23	6	19	MSP	Benign tissue	7
Wang et al^Citation6	China	Asian	Thyroid carcinoma	10	0	25	63	MSP	Normal tissue	6
Lee et al^Citation7	Sweden	Caucasian	Follicular thyroid carcinoma	16	5	3	18	MSP	Normal tissue	7
Nakamura et al^Citation8	USA	Caucasian	Thyroid carcinoma	27	0	51	27	MSP	Adjacent tissue	7
Xing et al^Citation9	USA	Caucasian	Thyroid carcinoma	14	0	32	19	QMSP	Normal tissue	7
Xing et al^Citation9	USA	Caucasian	Thyroid carcinoma	14	0	5	4	QMSP	Benign tissue	7
Schagdarsurengin et al^Citation10	Germany	Caucasian	Thyroid carcinoma	3	1	11	27	MSP	Normal tissue	6
Normal and adjacent tissue
Brait et al^Citation2	USA	Caucasian	Thyroid carcinoma	1	13	5	38	QMSP	Normal tissue	6
Qu and Xue^Citation3	People’s Republic of China	Asian	Thyroid carcinoma	21	7	13	15	MSP	Adjacent tissue	8
Wang et al^Citation6	People’s Republic of China	Asian	Thyroid carcinoma	10	0	25	63	MSP	Normal tissue	6
Lee et al^Citation7	Sweden	Caucasian	Follicular thyroid carcinoma	16	5	3	18	MSP	Normal tissue	7
Nakamura et al^Citation8	USA	Caucasian	Thyroid carcinoma	27	0	51	27	MSP	Adjacent tissue	7
Xing et al^Citation9	USA	Caucasian	Thyroid carcinoma	14	0	32	19	QMSP	Normal tissue	7
Schagdarsurengin et al^Citation10	Germany	Caucasian	Thyroid carcinoma	3	1	11	27	MSP	Normal tissue	6
Benign tissue
Brait et al^Citation2	USA	Caucasian	Thyroid carcinoma	1	43	5	38	QMSP	Benign tissue	6
Dai et al^Citation4	People’s Republic of China	Asian	Thyroid carcinoma	22	10	20	30	MSP	Benign tissue	8
Xing et al^Citation9	USA	Caucasian	Thyroid carcinoma	14	0	5	4	QMSP	Benign tissue	7
Mohammadi et al^Citation5	Iran	Caucasian	Thyroid carcinoma	2	23	6	19	MSP	Benign tissue	7

Abbreviations: M, methylation sample; MSP, methylation-specific PCR; NOS, Newcastle–Ottawa scale; NR, not reported; PCR, polymerase chain reaction; QMSP, quantitative methylation-specific PCR; U, unmethylation sample.

Table S2 Meta-analysis table

Variables	Controls/cases (n)	OR	95% CI	I^2 (%)	P-value
Heterogeneity
Total	136/365	5.94	2.09–16.89	55.40	0.028
Ethnicity
Caucasian	98/249	5.4	1.40–20.86	59.60	0.03
Asian	38/116	10.02	0.63–159.62	70.30	0.066
Disease type
FTC	104/94	11.88	5.80–24.32	51.50	0.067
PTC	152/133	2.18	0.48–9.83	68.40	0.007
Sample type
Normal tissue	81/259	5.85	1.43–23.91	62.60	0.02
Adjacent tissue	55/106	7.29	0.77–69.05	58.10	0.122
Pathogenesis
Distant metastasis	183/67	1.18	0.64–2.16	34.60	0.191
TNM-stage	64/32	1.79	0.72–4.44	52.60	0.121

Abbreviations: CI, confidence interval; FTC, follicular thyroid carcinoma; OR, odds ratio; PTC, papillary thyroid cancer.

Table S3 TNM-stage

References	Country	Ethnicity	Histology	Thyroid tumor				Methods
				TNM-stage I		TNM-stage II–IV
				U (n)	M (n)	U (n)	M (n)
Santoro et al^Citation1	Italy	Caucasian	Thyroid carcinoma	3	3	6	6	MSP
Qu and Xue^Citation2	People’s Republic of China	Asian	Thyroid carcinoma	13	7	1	7	MSP
Dai et al^Citation4	People’s Republic of China	Asian	Thyroid carcinoma	15	23	5	7	MSP

Abbreviations: M, methylation sample; MSP, methylation-specific PCR; PCR, polymerase chain reaction; U, unmethylation sample.

Table S4 Distant metastasis

References	Country	Ethnicity	Histology	Thyroid tumor				Methods
				M0 stage		M1 stage
				U (n)	M (n)	U (n)	M (n)
Santoro et al^Citation1	Italy	Caucasian	Thyroid carcinoma	6	8	3	1	MSP
Qu and Xue^Citation3	People’s Republic of China	Asian	Thyroid carcinoma	11	8	3	6	MSP
Dai et al^Citation4	People’s Republic of China	Asian	Thyroid carcinoma	16	27	4	3	MSP
Wang et al^Citation6	People’s Republic of China	Asian	Thyroid carcinoma	30	43	3	13	MSP
Schagdarsurengin et al^Citation10	Germany	Caucasian	Thyroid carcinoma	11	23	11	20	MSP

Abbreviations: M, methylation sample; MSP, methylation-specific PCR; PCR, polymerase chain reaction; U, unmethylation sample.

Table S5 Papillary thyroid carcinoma

References	Country	Ethnicity	Histology	Control		PTC			Methods
				U (n)	M (n)	U (n)	M (n)
Qu and Xue^Citation3	People’s Republic of China	Asian	Thyroid carcinoma	21	7	13		15	MSP
Wang et al^Citation6	People’s Republic of China	Asian	Thyroid carcinoma	10	0	19		42	MSP
Nakamura et al^Citation8	USA	Caucasian	Thyroid carcinoma	27	0	23		11	MSP
Xing et al^Citation9	USA	Caucasian	Thyroid carcinoma	14	0	24		6	QMSP
Schagdarsurengin et al^Citation10	Germany	Caucasian	Thyroid carcinoma	3	1	5		8	MSP

Abbreviations: M, methylation sample; MSP, methylation-specific PCR; PCR, polymerase chain reaction; PTC, papillary thyroid cancer; QMSP, quantitative methylation-specific PCR; U, unmethylation sample.

Table S6 Follicular thyroid carcinoma

References	Country	Ethnicity	Histology	Control		FTC		Methods
				U (n)	M (n)	U (n)	M (n)
Qu and Xue^Citation3	People’s Republic of China	Asian	Thyroid carcinoma	21	7	13	15	MSP
Lee et al^Citation7	Sweden	Caucasian	Follicular thyroid carcinoma	16	5	3	18	MSP
Schagdarsurengin et al^Citation10	Germany	Caucasian	Thyroid carcinoma	3	1	3	7	MSP
Xing et al^Citation9	USA	Caucasian	Thyroid carcinoma	3	9	14	0	QMSP
Wang et al^Citation6	People’s Republic of China	Asian	Thyroid carcinoma	1	14	10	0	MSP
Nakamura et al^Citation8	USA	Caucasian	Thyroid carcinoma	4	4	27	0	MSP

Abbreviations: FTC, follicular thyroid carcinoma; M, methylation sample; MSP, methylation-specific PCR; PCR, polymerase chain reaction; QMSP, quantitative methylation-specific PCR; U, unmethylation sample.

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QuFXueWJRASSF1A methylation and its clinical roles in papillary thyroid carcinomaJ Nantong University (Medical Sciences)201232490491

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NakamuraNCarneyJAJinLRASSF1A and NORE1A methylation and BRAFV600E mutations in thyroid tumorsLab Invest20058591065107515980887

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XingMCohenYMamboEEarly occurrence of RASSF1A hypermethylation and its mutual exclusion with BRAF mutation in thyroid tumorigenesisCancer Res20046451664166814996725

 PubMedGoogle Scholar

SchagdarsurenginUGimmOHoang-VuCDralleHPfeiferGPDammannRFrequent epigenetic silencing of the CpG island promoter of RASSF1A in thyroid carcinomaCancer Res200262133698370112097277

 PubMed Web of Science ®Google Scholar

SantoroAPannoneGCarosiMABRAF mutation and RASSF1A expression in thyroid carcinoma of southern ItalyJ Cell Biochem201311451174118223192464

 PubMedGoogle Scholar

BraitMLoyoMRosenbaumECorrelation between BRAF mutation and promoter methylation of TIMP3, RARbeta2 and RASSF1A in thyroid cancerEpigenetics20127771071922694820

 PubMed Web of Science ®Google Scholar

QuFXueWJRASSF1A methylation and its clinical roles in papillary thyroid carcinomaJ Nantong University (Medical Sciences)201232490491

 Google Scholar

DaiYLCaiDHChenHZhangZZhangHLiJThe association of the methylation of TSHR and RASSF1A with thyroid cancerShaanxi Med J2011401114461449

 Google Scholar

Mohammadi-aslJLarijaniBKhorgamiZQualitative and quantitative promoter hypermethylation patterns of the P16, TSHR, RASSF1A and RARbeta2 genes in papillary thyroid carcinomaMed Oncol20112841123112820535589

 PubMedGoogle Scholar

WangXHZhangGCLiuYLSunGFNongWXYaoESThe detection of RASSF1A promoter methylation in thyroid tumor patientsShaanxi Med J200938790792

 Google Scholar

LeeJJGeliJLarssonCGene-specific promoter hypermethylation without global hypomethylation in follicular thyroid cancerInt J Oncol200833486186918813801

 PubMed Web of Science ®Google Scholar

NakamuraNCarneyJAJinLRASSF1A and NORE1A methylation and BRAFV600E mutations in thyroid tumorsLab Invest20058591065107515980887

 PubMedGoogle Scholar

XingMCohenYMamboEEarly occurrence of RASSF1A hypermethylation and its mutual exclusion with BRAF mutation in thyroid tumorigenesisCancer Res20046451664166814996725

 PubMedGoogle Scholar

SchagdarsurenginUGimmOHoang-VuCDralleHPfeiferGPDammannRFrequent epigenetic silencing of the CpG island promoter of RASSF1A in thyroid carcinomaCancer Res200262133698370112097277

 PubMed Web of Science ®Google Scholar