186
M. Irfan et al.
approaches are required to identify potential inhibitors of invasion and metastasis of
HCC. Rong et al. 2016 selected HCC metastasis- and cell-specific DNA aptamers
by applying cell-SELEX to HCCLM9 as target cells. One of the selected aptamers,
LY-1, could specifically bind to metastatic HCC with a dissociation constant (Kd) in
nanomolar range. An in vitro reduction in migration and invasion of HCCLM9 cells
along with in vivo suppression of xenograft growth was observed after treatment
of highly metastatic cells with LY-1. It could be a potential molecular probe and
promising chemotherapeutic agent against metastatic HCC, after taken together its
tumor targeting and tumor suppressive effects [43].
The cancer stem cells (CSCs) are responsible for pathogenesis, heterogeneity,
malignant degree, anticancer therapy resistance, and recurrence of tumors. Pancreatic
cancer is also one of the most lethal and common cancers caused by CSCs. The
stepping stone for treatment of this cancer is identification of cancer stem cells
(CSCs) [44]. Kim et al. 2017 reported pancreatic CSC-associated aptamers as a
novel tool for diagnosis and therapeutic agents. Aptamer-positive cells showed high
expression levels of CSC-associated genes compared with the aptamer-negative cells
by fluorescent-activated cell sorting (FACS) analysis. So, these pancreatic CSCassociated aptamers may be potential candidates for novel diagnostic markers, CSCtargeting drug delivery, or circulating tumor cell detection [45].
Ovarian cancer is another lethal cancer with poor long-term prognosis and few
treatment options, most often because of its identification in late stages. Singlestranded DNA aptamers specific to ovarian tumor cells were identified that can
specifically bind to tumor biomarkers, can be conjugated and functionalized by small
molecules, and can aid in early diagnosis of neoplastic disorders. It suggests their
physiological relevance and potential use in clinical applications [46]. Jiang et al.
2020 reported a recent advancement in personalized treatment of ovarian cancer as
novel miR-29b-loaded aptamer (AS1411)-directed liposome that could potentially
serve as a new platform to improve the therapeutic outcome [47].
In personalized therapeutics, anticancer agents loaded in aptamer functionalized
nanoparticles are being used for targeted delivery. It is proved to be an attractive
strategy which reduced their toxicity while increasing therapeutic efficacy. The
researcher used this therapeutic technique for targeted delivery of doxorubicin (DOX)
to colon cancer cells against epithelial cell adhesion molecule (EpCAM). They used
DOX-loaded mesoporous silica nanoparticles (MSN) guided by modified aptamer
(Ap). The results showed that Ap-MSN-DOX system improved therapeutic index
while reducing side effects. So, it was suggested that the devised system has great
potential for the targeted delivery of therapeutic agents into EpCAM positive colon
cancer cells [48].
Reviewing the situation of personalized anticancer therapeutics necessitates their
search of effective molecular agents and probes. Currently, there is a lack of early
diagnosis and efficient therapeutics for cholangiocarcinoma (CCA), which is an
aggressive biliary tract malignancy as well. Wan et al. 2015 reported a 23 nt truncated
sequence aptamer in specific recognition of human cholangiocarcinoma QBC-939
M. Irfan et al.
approaches are required to identify potential inhibitors of invasion and metastasis of
HCC. Rong et al. 2016 selected HCC metastasis- and cell-specific DNA aptamers
by applying cell-SELEX to HCCLM9 as target cells. One of the selected aptamers,
LY-1, could specifically bind to metastatic HCC with a dissociation constant (Kd) in
nanomolar range. An in vitro reduction in migration and invasion of HCCLM9 cells
along with in vivo suppression of xenograft growth was observed after treatment
of highly metastatic cells with LY-1. It could be a potential molecular probe and
promising chemotherapeutic agent against metastatic HCC, after taken together its
tumor targeting and tumor suppressive effects [43].
The cancer stem cells (CSCs) are responsible for pathogenesis, heterogeneity,
malignant degree, anticancer therapy resistance, and recurrence of tumors. Pancreatic
cancer is also one of the most lethal and common cancers caused by CSCs. The
stepping stone for treatment of this cancer is identification of cancer stem cells
(CSCs) [44]. Kim et al. 2017 reported pancreatic CSC-associated aptamers as a
novel tool for diagnosis and therapeutic agents. Aptamer-positive cells showed high
expression levels of CSC-associated genes compared with the aptamer-negative cells
by fluorescent-activated cell sorting (FACS) analysis. So, these pancreatic CSCassociated aptamers may be potential candidates for novel diagnostic markers, CSCtargeting drug delivery, or circulating tumor cell detection [45].
Ovarian cancer is another lethal cancer with poor long-term prognosis and few
treatment options, most often because of its identification in late stages. Singlestranded DNA aptamers specific to ovarian tumor cells were identified that can
specifically bind to tumor biomarkers, can be conjugated and functionalized by small
molecules, and can aid in early diagnosis of neoplastic disorders. It suggests their
physiological relevance and potential use in clinical applications [46]. Jiang et al.
2020 reported a recent advancement in personalized treatment of ovarian cancer as
novel miR-29b-loaded aptamer (AS1411)-directed liposome that could potentially
serve as a new platform to improve the therapeutic outcome [47].
In personalized therapeutics, anticancer agents loaded in aptamer functionalized
nanoparticles are being used for targeted delivery. It is proved to be an attractive
strategy which reduced their toxicity while increasing therapeutic efficacy. The
researcher used this therapeutic technique for targeted delivery of doxorubicin (DOX)
to colon cancer cells against epithelial cell adhesion molecule (EpCAM). They used
DOX-loaded mesoporous silica nanoparticles (MSN) guided by modified aptamer
(Ap). The results showed that Ap-MSN-DOX system improved therapeutic index
while reducing side effects. So, it was suggested that the devised system has great
potential for the targeted delivery of therapeutic agents into EpCAM positive colon
cancer cells [48].
Reviewing the situation of personalized anticancer therapeutics necessitates their
search of effective molecular agents and probes. Currently, there is a lack of early
diagnosis and efficient therapeutics for cholangiocarcinoma (CCA), which is an
aggressive biliary tract malignancy as well. Wan et al. 2015 reported a 23 nt truncated
sequence aptamer in specific recognition of human cholangiocarcinoma QBC-939