Table 1

Frequency of methylation of the APC gene promoter 1A in breast and lung cancers, cancer cell lines, and control tissues

The differences in methylation frequencies between SCLC and NSCLC lines were significant (two-sided P = 0.001; Fisher’s exact test) for all samples.
SamplesNo. testedNo. methylated (%)a
Breast carcinoma
 Primary breast cancers4219 (45)
 Breast cancer cell lines3515 (42)
 Total breast cancer samples7734 (44)
SCLC
 Cell lines5013 (26)
NSCLC
 Primary tumors4822 (46)
 Cell linesa5834 (59)
 Total NSCLC samples10656 (53)
Nonmalignant tissues
 Peripheral blood lymphocytesb100 (0)
 Buccal swabsb120 (0)
 Nonmalignant breastc283 (11)
 Nonmalignant peripheral lungc180 (0)
  Total nonmalignant samples683 (4)
  • a The APC gene methylation frequency by tumor subtype was 72% (18 of 25) in adenocarcinomas, 50% (3 of 6) in squamous cell carcinomas, and 48% (13 of 27) in other subtypes (large cells, carcinoids, and mixed tumors).

  • b From healthy volunteers.

  • c From resections for breast and lung cancers.