14 Perspectives of Aptamers for Medical Applications
425
specified that patients diagnosed with acute myocardial infarction (AMI)-, the most
immediately life-threatening syndrome leading to particularly severe cardiac events,
e.g., irreversible damage in the myocardium, have a saliva cTnI level as high as
675 pg mL
−1 [124].
B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide
(NT-pro-BNP) have been recognized as powerful cardiovascular biomarkers for acute
heart failure. BNP is a desirable biomarker for heart failure because of its short
circulation time of about 20 min, which permits its release and diffusion rapidly
from injured tissue to the blood [125]. In healthy patients, the BNP blood level is
low (20 pg mL
−1 ; 6 pM) and only rises to 2 ng mL
−1 (600 pM) in patients with
acute heart failure [126]. It brings the big challenge for its application as biomarker
in clinical scenarios.
A variety of different methods have been developed for BNP assay. Grabowska
et al. [127] first reported a electrochemical biosensors for BNP with a detection limit
of 20–40 pg mL
−1 ; the assay is rather time-consuming to complete (2 h), and the
analysis has to be performed in a deaerated alkaline solution. Bruno et al. [128]
developed an aptamer–magnetic bead electrochemiluminescence sandwich assay
with a ultrasensitive, low pg/mL detection limit for BNP in serum. Recently, Tu et al.
[129] developed a cost-effective fluorescence resonance energy transfer (FRET) platform for the detection of B-type natriuretic peptide (BNP), based on the ON (strong
emission) and OFF (quenching) states of FRET in the presence and absence of
BNP, respectively, specific detection of BNP was achieved in the range of 0.074–
0.56 pg/mL with a limit of detection as low as 45 fg/mL. This platform was also
applied to detect BNP in 45 blood samples, which demonstrated a close correlation
(r = 0.961; P = 0.000) to that traditional method with improved specificity (68.8
versus 65.6%) and positive predictive value (33.3 versus 31.3%) in heart failure
diagnosis. Table 14.3 tabulated sequences info of aptamers for biomarkers of
cardiovascular diseases.
14.3.3.2 Pelvic Cancer
Women reproductive organs are commonly affected by various cancers including
ovarian, cervical, endometrial, vaginal, fallopian tube, and vulvar cancers. Earlier
diagnosis of these cancers will improve the life quality of women. Applications of
aptamers and aptamer-nanomaterial conjugates for cancer detection and therapy have
attracted increasing attention nowadays. Aptamers for a lot of gynecological cancer
biomarkers which include HE4, CA125, VEGF, OCCA (for ovarian cancer), EGFR,
FGFR1, K-ras (for endometrial cancer), HPV E-16, HPV E-7, HPV E-6, tyrosine,
and kinase (for cervical cancer) have been generated successively, which help to
identify the cancers in woman reproductive organs.
CA 125 (cancer antigen 125) is a transmembrane glycoprotein which is the only
Food and Drug Administration (FDA) approved biomarker for ovarian cancer. It is
expressed on the cell surface and released into the blood serum. Elevation of CA125
in blood is closely correlated with different stages of ovarian cancer. Chen et al. [130]
425
specified that patients diagnosed with acute myocardial infarction (AMI)-, the most
immediately life-threatening syndrome leading to particularly severe cardiac events,
e.g., irreversible damage in the myocardium, have a saliva cTnI level as high as
675 pg mL
−1 [124].
B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide
(NT-pro-BNP) have been recognized as powerful cardiovascular biomarkers for acute
heart failure. BNP is a desirable biomarker for heart failure because of its short
circulation time of about 20 min, which permits its release and diffusion rapidly
from injured tissue to the blood [125]. In healthy patients, the BNP blood level is
low (20 pg mL
−1 ; 6 pM) and only rises to 2 ng mL
−1 (600 pM) in patients with
acute heart failure [126]. It brings the big challenge for its application as biomarker
in clinical scenarios.
A variety of different methods have been developed for BNP assay. Grabowska
et al. [127] first reported a electrochemical biosensors for BNP with a detection limit
of 20–40 pg mL
−1 ; the assay is rather time-consuming to complete (2 h), and the
analysis has to be performed in a deaerated alkaline solution. Bruno et al. [128]
developed an aptamer–magnetic bead electrochemiluminescence sandwich assay
with a ultrasensitive, low pg/mL detection limit for BNP in serum. Recently, Tu et al.
[129] developed a cost-effective fluorescence resonance energy transfer (FRET) platform for the detection of B-type natriuretic peptide (BNP), based on the ON (strong
emission) and OFF (quenching) states of FRET in the presence and absence of
BNP, respectively, specific detection of BNP was achieved in the range of 0.074–
0.56 pg/mL with a limit of detection as low as 45 fg/mL. This platform was also
applied to detect BNP in 45 blood samples, which demonstrated a close correlation
(r = 0.961; P = 0.000) to that traditional method with improved specificity (68.8
versus 65.6%) and positive predictive value (33.3 versus 31.3%) in heart failure
diagnosis. Table 14.3 tabulated sequences info of aptamers for biomarkers of
cardiovascular diseases.
14.3.3.2 Pelvic Cancer
Women reproductive organs are commonly affected by various cancers including
ovarian, cervical, endometrial, vaginal, fallopian tube, and vulvar cancers. Earlier
diagnosis of these cancers will improve the life quality of women. Applications of
aptamers and aptamer-nanomaterial conjugates for cancer detection and therapy have
attracted increasing attention nowadays. Aptamers for a lot of gynecological cancer
biomarkers which include HE4, CA125, VEGF, OCCA (for ovarian cancer), EGFR,
FGFR1, K-ras (for endometrial cancer), HPV E-16, HPV E-7, HPV E-6, tyrosine,
and kinase (for cervical cancer) have been generated successively, which help to
identify the cancers in woman reproductive organs.
CA 125 (cancer antigen 125) is a transmembrane glycoprotein which is the only
Food and Drug Administration (FDA) approved biomarker for ovarian cancer. It is
expressed on the cell surface and released into the blood serum. Elevation of CA125
in blood is closely correlated with different stages of ovarian cancer. Chen et al. [130]