DNA Methylation of the Homeobox Genes PITX2 and SHOX2 Predicts Outcome in Non–small-cell Lung Cancer Patients

Abstract

Biomarkers that facilitate prediction of disease progression in lung cancer patients might be clinically valuable in optimizing individualized therapy. In this study, the ability of the DNA methylation biomarkers PITX2 and SHOX2 to predict disease outcome in lung cancer patients has been evaluated. Quantitative, methylation-specific (HeavyMethyl), real-time polymerase chain reaction assays were used to measure DNA methylation of PITX2 and SHOX2 in bisulfite-converted DNA from formalin-fixed, paraffin-embedded tissues from 474 non-small-cell lung cancer patients. In univariate Cox Proportional Hazard analysis, high methylation of SHOX2 and PITX2 was a significant predictor of progression-free survival [SHOX2: n=465, hazard ratio (HR)=1.395 (1.130 to 1.721), P=0.002; PITX2: n=445, HR=1.312 (1.059 to 1.625), P=0.013]. Patients with low methylation of either PITX2 and/or SHOX2 (n=319) showed a significantly higher risk of disease progression as compared with patients with higher methylation of both genes [n=126; HR=1.555 (1.210 to 1.999), P=0.001]. This was particularly true for the subgroup of patients receiving no adjuvant radiotherapy or chemotherapy [n=258, HR=1.838 (1.252 to 2.698), P=0.002]. In multivariate analysis, both biomarkers added significant independent prognostic information to pT, pN, pM, and grade. Another interesting finding of this study was that SHOX2 and PITX2 DNA methylation was shown to be inversely correlated with TTF1 (also known as NKX2-1) expression (PITX2: P=0.018, SHOX2: P<0.001). TFF1 expression was previously found to be associated with improved survival in the same patient cohort. DNA methylation of PITX2 and SHOX2 is an independent prognostic biomarker for disease progression in non-small-cell lung cancer patients.

SOCS3 Modulates the Response to Enzalutamide and Is Regulated by Androgen Receptor Signaling and CpG Methylation in Prostate Cancer Cells

“…Methylation analysis of the SOCS3 promoter region was performed as previously described (25,26). Briefly, DNA was isolated from formalin-fixed, paraffin-embedded (FFPE) tissue blocks and subsequently converted with bisulfite using the InnuCONVERT Bisulfite All-In-One Kit (Analytik Jena) as previously described (27).…”

“…All qPCRs were run in triplicate. Relative methylation levels were computed using the DDC t method as previously described (25).…”

Development and Clinical Validation of a Real-Time PCR Assay for PITX2 DNA Methylation to Predict Prostate-Specific Antigen Recurrence in Prostate Cancer Patients Following Radical Prostatectomy

“…8,9 DNA methylation of the PITX2 gene locus has been established in several studies as a prognostic biomarker in various cancers. Methylation of PITX2 has been reported to be strongly associated with disease outcome in lung cancer patients 10 and in hormone receptorepositive breast cancer patients. 11e14 In addition, PITX2 methylation was found to be strongly associated with BCR in prostate cancer patients who received radical prostatectomy.…”

Analysis of Gene Methylation Shox2, Tgfbr1, Mir-375 in Different Types of Lung Cancer

“…Увеличение числа копий гена SHOX2 было признано одним из самых распро-страненных и значимых хромосомных пере-строек при раке легкого [7][8][9][10][11]. В то же время, ненормальное метилирование гена SHOX2 является отличительной чертой раковых опухо-лей легких и коррелирует с увеличением числа копий участка локуса 3q25.3 [12,13].…”

“…Стоит отметить, что метилирование гена SHOX2 наблюдается в раз-личных гистологических подтипах рака легких [12,[14][15][16], с особенно высокой частотой при мелкоклеточном и плоскоклеточном раке лег-кого [16]. Однако, в настоящее время не хватает информации о молекулярном механизме регу-лирования SHOX2.…”