Evaluation of a simple method for storage of blood samples that enables isolation of circulating tumor cells 96 h after sample collection

Table 1 Endpoint PCR data

Storage time (h)	Gene expression in CD45-negative cells from healthy individuals
Storage time (h)	18S rRNA	ACTB	EPCAM	KRT19	PECAM1	CDH2
0	+	+	−	−	+	−
24	+	+	−	−	+	−
48	+	+	−	−	+	−
72	+	+	−	−	+	−
96	+	+	−	−	+	−

Storage time (h)	Gene expression in breast-cancer cells spiked into blood from healthy individuals
Storage time (h)	18S rRNA	ACTB	EPCAM	KRT19	PECAM1	CDH2
0	+	+	+	+	−	+
24	+	+	+	+	−	+
48	+	+	+	+	−	+
72	+	+	+	+	−	+
96	+	+	+	−	−	−

Storage time (h)	Gene expression in colon-cancer cells spiked into blood from healthy individuals
Storage time (h)	18S rRNA	ACTB	EPCAM	KRT19	PECAM1	CDH2
0	+	+	+	+	−	+
24	+	+	+	+	−	+
48	+	+	+	+	−	+
72	+	+	+	+	−	+
96	+	+	+	−	−	−

Expression of genes was determined electrophoretically by the presence of a product band at the end of PCR. “+” indicates expression, whereas “−” indicates the absence of expression

ISSN: 2241-5793