Evaluation of plakophilin-3 mRNA as a biomarker for detection of circulating tumor cells in gastrointestinal cancer patients.
BACKGROUND
This study aims to assess Plakophilin-3 (PKP3) as a surrogate biomarker of circulating tumor cells in patients with gastrointestinal cancer.


METHODS
The primary aim is to estimate the diagnostic accuracy of PKP3 real-time reverse transcriptase-PCR in blood. Receiver operating characteristic curves were constructed. Correlations between the blood PKP3 levels and the clinicopathologic features of the study subjects were analyzed. Logistic regression was used to predict outcomes based on PKP3.


RESULTS
Sixty-four patients with gastrointestinal cancer and 23 controls were included. The mean relative PKP3 mRNA expression was 48.45 in cancer patients and 2.8 in controls (P < 0.0001). Comparing the PKP3 levels in patients and controls, the area under the curve was 0.852 (95% confidence interval, 0.76-0.94; P < 0.0001) in receiver operating characteristic analysis. A higher blood level of PKP3 mRNA was associated with a more advanced stage (P = 0.025), pT(3-4) tumors (P = 0.028), metastasis (P = 0.021), and residual (R2) disease (P = 0.037). Higher PKP3 mRNA was associated with the risk of cancer progression and death (odds ratio, 3.875; 95% confidence interval, 1.781-8.430; P = 0.001).


CONCLUSIONS
Increased PKP3 mRNA was detected in the blood of gastrointestinal cancer patients. Significant correlations were found with advanced stage, pT(3-4), metastatic disease, and the residual disease status. PKP3 mRNA in blood was associated with the risk of cancer progression and death.


CONCLUSIONS
PKP3 mRNA can be used as a marker of subclinical disease in gastrointestinal cancer and thus holds potential clinical relevance as a predictor for disease outcome.
Valladares-Ayerbes
Manuel
M
Medical Oncology, University Hospital, La Coruña, Spain. manuel.valladares.ayerbes@sergas.es
Díaz-Prado
Silvia
S
Reboredo
Margarita
M
Medina
Vanessa
V
Lorenzo-Patiño
Maria J
MJ
Iglesias-Díaz
Pilar
P
Haz
Mar
M
Pértega
Sonia
S
Santamarina
Isabel
I
Blanco
Moises
M
Quindós-Varela
Maria
M
Figueroa
Angélica
A
Antón-Aparicio
Luis M
LM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood / Q000235:genetics*; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000097:blood* / Q000235:genetics / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology; D051191:Plakophilins / Q000097:blood / Q000235:genetics*; D011237:Predictive Value of Tests; D012333:RNA, Messenger / Q000097:blood* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
D014408:Biomarkers, Tumor; C495339:PKP3 protein, human; D051191:Plakophilins; D012333:RNA, Messenger