Potential and application of abortive transcripts as a novel molecular marker of cancers

Table 1 Protein tumor biomarkers

Biomarker	Alteration	Related tumor	Detection method	Advantage	Disadvantage	Ref.
AFP	Up-regulation	Primary liver cancer, viral hepatitis, liver cirrhosis, gonad embryonic tumor, etc.	Blood	The most sensitive and specific index for early diagnosis of primary liver cancer, and suitable for large-scale census	For patients with early liver cancer, the detection rate of AFP is low and the misdiagnosis rate is high	[43]
CEA	Up-regulation	Colon cancer, rectal cancer, pancreatic cancer, gastric cancer, lung cancer, etc.	Blood	A broad-spectrum tumor marker	The specificity is not strong, the sensitivity is not high, and the early diagnosis of tumor is not obvious	[44-46]
PSA	Up-regulation	Prostate cancer	Blood	Avoid some unnecessary biopsies	Benign prostatic hyperplasia and prostatitis can also show positive PSA	[47]
SCCA	Up-regulation	Cervical cancer, lung squamous cell carcinoma, head and neck cancer, etc.	Blood and tissue	High specificity	Low sensitivity	[48-49]
CYFRA21-1	Up-regulation	Lung cancer, esophageal cancer, hepatocellular carcinoma, etc.	Blood	The sensitivity and specificity of the diagnosis for bladder cancer are good	Screening for lung cancer is not highly specific	[50-52]
TPA	Up-regulation	Lung cancer, breast cancer, ovarian cancer, bladder cancer	Blood	High detection rate for malignant tumors, and high sensitivity in the observation of curative effect	Has no correlation with tumor site or tissue type	[53-56]
HE4	Up-regulation	Ovarian cancer	Blood	High sensitivity and specificity for the diagnosis of ovarian cancer, especially in early ovarian cancer, and related to the stage and metastasis of ovarian cancer	A high positive rate in endometrial cancer	[57]

AFP: Alpha-fetoprotein; CEA: Carcinoembryonic antigen; PSA: Prostate specific antigen; SCCA: Squamous cell carcinoma antigen; CYFRA21-1: Cytokeratin 19 fragment; TPA: Tissue polypeptide antigen; HE4: Human epididymal protein 4.

Table 2 Glycochain antigen tumor biomarkers

Biomarker	Alteration	Related tumor	Detection method	Advantage	Disadvantage	Ref.
CA125	Up-regulation	Ovarian cancer	Blood	High sensitivity of diagnosis	Poor specificity, nearly half of early cases are not elevated	[58]
CA15-3	Up-regulation	Lung cancer, colon cancer, pancreatic cancer, ovarian cancer, breast cancer, etc.	Blood	The most important specific marker for breast cancer	Low sensitivity in the early stages of breast cancer	[59]
CA19-9	Up-regulation	Pancreatic cancer, gallbladder cancer	Blood	The sensitivity and specificity can reach more than 90%	The elevation of CA19-9 is susceptible to many benign diseases	[60-61]
CA50	Up-regulation	Pancreatic cancer, colon cancer, liver cirrhosis, lung cancer	Blood	Double identify Lewis antigen negative and positive tumors, a broader broad-spectrum tumor marker than CA19-9	Inflammation of the gastrointestinal tract may cause mild or transient elevation of CA50	[62]

CA125: Glycochain antigen 125; CA15-3: Glycochain antigen 15-3; CA19-9: Glycochain antigen 19-9; CA50: Glycochain antigen 50.

Table 3 Enzymatic tumor biomarkers

Biomarker	Alteration	Related tumor	Detection method	Advantage	Disadvantage	Ref.
NSE	Up-regulation	Small cell lung cancer	Blood	The diagnostic sensitivity can reach 80% and the specificity can reach 80%-90%	NSE alone is not sufficient to accurately differentiate SCLC from NSCLC	[63]
ProGRP	Up-regulation	Small cell lung cancer	Blood	High sensitivity and specificity	Insufficiency of kidney function can also lead to elevated ProGRP values	[64]
PAP	Up-regulation	Prostate cancer	Blood	An auxiliary index for tumor grading	Serum PAP may be elevated in some patients with benign prostatic hyperplasia	[65]

NSE: Neuron specific enolase; ProGRP: Gastrin releases peptide precursors; PAP: Prostatic acid phosphatase.