HSPA6 and cancer: Then, further mechanistic study showed that, although the mRNA levels of HSPA6 were increased in breast cancer tissues compared with matched normal tissues, the promoter regions of HSPA6 in BRCA samples were increased in cancer tissues compared with matched normal tissues, indicating that DNA methylation of HSPA6 may not be the regulatory mechanism for HSPA6 mRNA upregulation in those breast cancer tissues.