Expression of the stem cell marker CD133 is related to tumor development in colorectal carcinogenesis

Cancer stem cell marker expression and methylation status in patients with colorectal cancer

The number of individuals diagnosed with colorectal cancer (CRC) has been on an alarming upward trajectory over the past decade. In some countries, this cancer represents one of the most frequently diagnosed types of neoplasia. Therefore, it is an important demand to study the pathology underlying this disease to gain insights into the mechanism of resistance to treatment. Resistance of tumors to chemotherapy and tumor aggressiveness have been associated with a minor population of neoplastic cells, which are considered to be responsible for tumor recurrence. These types of neoplastic cells are known as cancer stem cells, which have been previously reported to serve an important role in pathogenesis of this malignant disease. Slovakia has one of the highest incidence rates of CRC worldwide. In the present study, the aim was to classify the abundance of selected stem cell markers (CD133, CD166 and Lgr5) in CRC tumors using flow cytometry. In addition, the methylation status of selected genomic regions of CRC biomarkers (ADAMTS16, MGMT, PROM1 (CD133), LGR5 and ALCAM) was investigated by pyrosequencing in a cohort of patients from Martin University Hospital, Martin, Slovakia. Samples from both primary tumors and metastatic tumors were tested. Analysis of DNA methylation in the genomic regions of indicated five CRC biomarkers was also performed, which revealed the highest levels of methylation in the A disintegrin and metalloproteinase with thrombospondin motifs 16 and O6-methyguanine-DNA methyl transferase genes, whereas the lowest levels of methylation were found in genes expressing prominin-1, leucine-rich repeat-containing G-protein-coupled receptor 5 and activated leukocyte cell adhesion molecule. Furthermore, tumor tissues from metastases showed significantly higher levels of CD133⁺ cells compared with that in primary tumors. Higher levels of CD133⁺ cells correlated with TNM stage and the invasiveness of CRC into the lymphatic system. Although relatively small number of samples was processed, CD133 marker was consider to be important marker in pathology of CRC.

ARE STEM CELL MARKER EXPRESSION AND CD133 ANALYSIS RELEVANT TO DIFFERENTIATE COLORECTAL CANCER?

Background:

CD133 and AXL have been described as cancer stem cell markers, and c-MYC as a key regulatory cellular mechanism in colorectal cancer (CRC).

Aim:

Evaluate the prognostic role of the biomarkers CD133, AXL and c-MYC and their association with clinicopathologic characteristics in colorectal adenocarcinomas and adenomas.

Methods:

A total of 156 patients with UICC stage I-IV adenocarcinomas (n=122) and adenomas (n=34) were analyzed. Tissue microarrays (TMA) from primary tumors and polyps for CD133, c-MYC and AXL expression were performed and analyzed for their significance with clinicopathologic characteristics.

Results:

Poorly differentiated adenocarcinomas and disease progression were independent risk factors for poor overall survival. The median overall survival time was 30 months. Positive CD133 expression (35.9% of all cases), particularly of right-sided CRCs (44.8% of the CD133+ cases), was negatively correlated with death in the univariate analysis, which did not reach significance in the multivariate analysis. c-MYC (15.4% of all cases) was predominantly expressed in advanced-stage patients with distant (non-pulmonary/non-hepatic) metastasis. AXL expression was found only occasionally, and predominantly dominated in adenomas, with less penetrance in high-grade dysplasia.

Conclusions:

CD133 expression was not associated with inferior overall survival in CRC. While AXL showed inconclusive results, c-MYC expression in primary CRCs was associated with distant metastasis.

Relationship between CD 163 Tumor-Associated Macrophages and Colorectal-Cancer Stem Cell Markers

BACKGROUND: Colorectal-cancer stem cells (CR-CSCs) represent a specific subpopulation of colorectal cancer (CRC) cells, which are characterized by the expression of CD133 and CD166. Tumor-associated macrophages (TAMs), found near CSCs may represent polarized macrophages, which are characterized by CD163 expression. In most tumors, TAMs may promote aggressive tumor development, leading to poor prognoses. AIM: The aim of this study was to determine whether any association exists between CD163 expression in TAMs and CD133 and CD166 expression in CR-CSCs. METHODS: This study used a cross-sectional design that was conducted at the General Hospital and affiliates in Medan, from September 2018 to July 2019. CRC tissues were collected from colonoscopy biopsies and surgical resections performed on CRC patients, who fulfilled all necessary inclusion and exclusion criteria and provided informed consent. Subjects were divided into high- and low-CD163-level groups. We analyzed the expression levels of CD163, CD133, and CD166 using immunohistochemical (IHC) assays. RESULTS: A total of 118 CRC patients were enrolled in this study, of whom 58.5% were male. No significant differences in hemoglobin, leukocyte, or platelet levels were observed between high- and low-level CD163 expression. We didn’t find any significant association of CD163 TAM with CRC histological grade and TNM stagings. Significant associations were found between the CD 163 expression level and the CD133 expression level (p < 0.001) and between the CD 163 expression level and the CD166 expression level (p< 0.001). Increased TAM levels of CD163 was associated with 2.770-fold and 2.616-fold increased risks of elevated CD133 and CD166 levels, respectively. CONCLUSION: An association was found between the expression levels of CD163 in TAMs and the expression levels of CD133 and CD166 in CR-CSCs.

FBXW11 contributes to stem-cell-like features and liver metastasis through regulating HIC1-mediated SIRT1 transcription in colorectal cancer

Colorectal tumorigenesis is a heterogeneous disease driven by multiple genetic and epigenetic alterations. F-box and WD repeat domain containing 11 (FBXW11) is a member of the F-box protein family that regulates the ubiquitination of key factors associated with tumor growth and aggressiveness. Our study aimed to explore the role of FBXW11 in the development and metastasis of colorectal cancer (CRC). FBXW11 was overexpressed in colorectal tumor tissues and its overexpression was associated with a poor prognosis of CRC patients. The upregulation of FBXW11 not only promoted cell proliferation, invasion, and migration, but also contributed to maintaining stem-cell features in colorectal tumor cells. Further analysis revealed that FBXW11 targeted hypermethylated in cancer 1 (HIC1) and reduced its stability in CRC cells through ubiquitination. Moreover, the expression of sirtuin 1 (SIRT1), a deacetylase in tumor cells was upregulated by FBXW11 via regulating HIC1 expression. The mouse xenograft models of CRC confirmed that FBXW11 knockdown impeded colorectal tumor growth and liver metastasis in vivo. In summary, our study identified FBXW11 as an oncogenic factor that contributed to stem-cell-like properties and liver metastasis in CRC via regulating HIC1-mediated SIRT1 expression. These results provide a rationale for the development of FBXW11-targeting drugs for CRC patients.

Beyond Colonoscopy: Exploring New Cell Surface Biomarkers for Detection of Early, Heterogenous Colorectal Lesions

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths among both men and women in the United States. Early detection and surgical removal of high-risk lesions in the colon can prevent disease from developing and spreading. Despite implementation of programs aimed at early detection, screening colonoscopies fail to detect a fraction of potentially aggressive colorectal lesions because of their location or nonobvious morphology. Optical colonoscopies, while highly effective, rely on direct visualization to detect changes on the surface mucosa that are consistent with dysplasia. Recent advances in endoscopy techniques and molecular imaging permit microscale visualization of the colonic mucosa. These technologies can be combined with various molecular probes that recognize and target heterogenous lesion surfaces to achieve early, real-time, and potentially non-invasive, detection of pre-cancerous lesions. The primary goal of this review is to contextualize existing and emergent CRC surface biomarkers and assess each’s potential as a candidate marker for early marker-based detection of CRC lesions. CRC markers that we include were stratified by the level of support gleaned from peer-reviewed publications, abstracts, and databases of both CRC and other cancers. The selected biomarkers, accessible on the cell surface and preferably on the luminal surface of the colon tissue, are organized into three categories: (1) established biomarkers (those with considerable data and high confidence), (2) emerging biomarkers (those with increasing research interest but with less supporting data), and (3) novel candidates (those with very recent data, and/or supportive evidence from other tissue systems). We also present an overview of recent advances in imaging techniques useful for visual detection of surface biomarkers, and discuss the ease with which these methods can be combined with microscopic visualization.

The shifting paradigm of colorectal cancer treatment: a look into emerging cancer stem cell-directed therapeutics to lead the charge toward complete remission

Introduction: Colorectal cancer (CRC) is one of the most common forms of cancer worldwide and is the second leading cause of cancer-related death in the United States. Despite advances in early detection, ~25% of patients are late stage, and treated patients have <12% chance of survival after five years. Tumor relapse and metastasis are the main causes of patient death. Cancer stem cells (CSCs) are a rare population of cancer cells characterized by properties of self-renewal, chemo- and radio-resistance, tumorigenicity, and high plasticity. These qualities make CSCs particularly important for metastasic seeding, DNA-damage resistance, and tumor repopulating.Areas Covered: The following review article focuses on the role of CRC-SCs in tumor initiation, metastasis, drug resistance, and tumor relapse, as well as on potential therapeutic options for targeting CSCs.Expert Opinion: Current studies are underway to better isolate and discriminate CSCs from normal stem cells and to produce CSC-targeted therapeutics. The intestinal receptor, guanylate cyclase C (GUCY2C) could potentially provide a unique therapeutic target for both non-stem cells and CSCs alike in colorectal cancer through immunotherapies. Indeed, immunotherapies targeting CSCs have the potential to break the treatment-recurrence cycle in the management of advanced malignancies.

Enrichment of cancer-initiating cells from colon cancer cells through porous polymeric membranes by a membrane filtration method

Cancer-initiating cells (CICs) or cancer stem cells (CSCs) are primarily responsible for tumor initiation, growth, and metastasis and represent a few percent of the total tumor cell population. We designed a membrane filtration protocol to enrich CICs (CSCs) from the LoVo colon cancer cell line via nylon mesh filter membranes with 11 and 20 μm pore sizes and poly(lactide-co-glycolic acid)/silk screen (PLGA/silk screen) porous membranes (pore sizes of 20-30 μm). The colon cancer cell solution was filtered through the membranes to obtain a permeate solution. Subsequently, the cell culture medium was filtered through the membranes to collect the recovery solution where the cells attached to the membranes were rinsed off into the recovery solution. Then, the membranes were cultivated in the cultivation medium to collect the migrated cells from the membranes. The cells migrated from any membrane had higher expression of the CSC surface markers CD44 and CD133, had higher colony formation levels, and produced more carcinoembryonic antigen (CEA) than the colon cancer cells cultivated on conventional tissue culture plates (control). We established a method to enrich the CICs (CSCs) of colon cancer cells from migrated cells through porous polymeric membranes by the membrane filtration protocol developed in this study.

ARE STEM CELL MARKER EXPRESSION AND CD133 ANALYSIS RELEVANT TO DIFFERENTIATE COLORECTAL CANCER?

Background:

CD133 and AXL have been described as cancer stem cell markers, and c-MYC as a key regulatory cellular mechanism in colorectal cancer (CRC).

Aim:

Evaluate the prognostic role of the biomarkers CD133, AXL and c-MYC and their association with clinicopathologic characteristics in colorectal adenocarcinomas and adenomas.

Methods:

A total of 156 patients with UICC stage I-IV adenocarcinomas (n=122) and adenomas (n=34) were analyzed. Tissue microarrays (TMA) from primary tumors and polyps for CD133, c-MYC and AXL expression were performed and analyzed for their significance with clinicopathologic characteristics.

Results:

Poorly differentiated adenocarcinomas and disease progression were independent risk factors for poor overall survival. The median overall survival time was 30 months. Positive CD133 expression (35.9% of all cases), particularly of right-sided CRCs (44.8% of the CD133+ cases), was negatively correlated with death in the univariate analysis, which did not reach significance in the multivariate analysis. c-MYC (15.4% of all cases) was predominantly expressed in advanced-stage patients with distant (non-pulmonary/non-hepatic) metastasis. AXL expression was found only occasionally, and predominantly dominated in adenomas, with less penetrance in high-grade dysplasia.

Conclusions:

CD133 expression was not associated with inferior overall survival in CRC. While AXL showed inconclusive results, c-MYC expression in primary CRCs was associated with distant metastasis.

A Novel Therapeutic Approach for Colorectal Cancer Stem Cells: Blocking the PI3K/Akt Signaling Axis With Caffeic Acid

Cancer stem cells (CSCs) have been identified in a multiple of cancer types and resistant to traditional cancer therapies such as chemotherapeutic agents and radiotherapy, which may destroy bulk tumor cells but not all CSCs, contributing to reformation tumor masses and subsequent relapse. Moreover, it is very difficult to effectively identify and eliminate CSCs because they share some common phenotypic and functional characteristics of normal stem cells. Therefore, finding better therapeutic strategies to selectively target CSCs might be helpful to reduce subsequent malignancies. In the present study, we found that caffeic acid effectively suppresses self-renewal capacity, stem-like characteristics, and migratory capacity of CD44+ and CD133+ colorectal CSCs in vitro and in vivo. In addition, we also revealed that PI3K/Akt signaling may be linked to multiple colorectal CSC-associated characteristics, such as radio-resistance, stem-like property, and tumorigenic potential. To the best of our knowledge, this is the first study demonstrating that caffeic acid effectively targets colorectal CSC populations by inhibiting the growth and/or self-renewal capacity of colorectal CSCs through PI3K/Akt signaling in vitro and in vivo.

Short tandem repeat profiling for the authentication of cancer stem-like cells

Colorectal and glioblastoma cancer stem‐like cells (CSCs) are essential for translational research. Cell line authentication by short tandem repeat (STR) profiling ensures reproducibility of results in oncology research. This technique enables to identify mislabeling or cross‐contamination of cell lines. In our study, we provide a reference dataset for a panel of colorectal and glioblastoma CSCs that allows authentication. Each cell line was entered into the cell Line Integrated Molecular Authentication database 2.1 to be compared to the STR profiles of 4485 tumor cell lines. This article also provides clinical data of patients from whom CSCs arose and data on the parent tumor stage and mutations. STR profiles and information of our CSCs are also available in the Cellosaurus database (ExPASy) as identified by unique research resource identifier codes.

Human cell lines obtained from cancer stem‐like cells represent an invaluable model for studying tumor properties. Cell line authentication by short tandem repeat (STR) profiling is an important tool to identify the potential mislabeling or cross‐contamination of cell lines. Here, the authors characterized 18 colorectal cancer stem‐like cell lines from 17 patients and 103 glioblastoma cancer stem‐like cell lines from 95 patients by STR profiling to create a reference dataset that allows the authentication of these cell lines and their identification through a unique research resource identifier. The results will help further ensure the reliability and reproducibility of research experiments.

Isolation and Characterization of Two Novel Colorectal Cancer Cell Lines, Containing a Subpopulation with Potential Stem-Like Properties: Treatment Options by MYC/NMYC Inhibition

Simple Summary

The aim of this study was to gain a better understanding of cancer stem cells, which are a small subpopulation of tumor cells with high plasticity driving tumor growth and metastasis. Here we isolated two novel colorectal cancer cell lines originating from a rectal neuroendocrine carcinoma and a colorectal adenocarcinoma, depicting stem-like properties. These in vitro models offer the possibility to evaluate pathophysiological mechanisms in order to develop tailored therapeutic strategies for distinct colorectal malignancies. Investigations revealed gene copy number gain of the N-myc proto-oncogene for both. Accordingly, inhibition of the protein–protein interaction of myc and N-myc proto-oncogenes with the myc-associated factor X utilizing small molecule KJ-Pyr-9, exhibited a significant reduction in survival of both cell lines by the induction of apoptosis. Consequently, the blockage of these interactions may serve as a possible treatment strategy for colorectal cancer cell lines with gene copy number gain of the N-myc proto-oncogene.

Abstract

Cancer stem cells (CSC) are crucial mediators of cancer relapse. Here, we isolated two primary human colorectal cancer cell lines derived from a rectal neuroendocrine carcinoma (BKZ-2) and a colorectal adenocarcinoma (BKZ-3), both containing subpopulations with potential stem-like properties. Protein expression of CSC-markers prominin-1 and CD44 antigen was significantly higher for BKZ-2 and BKZ-3 in comparison to well-established colon carcinoma cell lines. High sphere-formation capacity further confirmed the existence of a subpopulation with potential stem-like phenotype. Epithelial–mesenchymal transition markers as well as immune checkpoint ligands were expressed more pronounced in BKZ-2. Both cell populations demonstrated N-myc proto-oncogene (NMYC) copy number gain. Myc proto-oncogene (MYC)/NMYC activity inhibitor all-trans retinoic acid (ATRA) significantly reduced the number of tumor spheres for both and the volume of BKZ-2 spheres. In contrast, the sphere volume of ATRA-treated BKZ-3 was increased, and only BKZ-2 cell proliferation was reduced in monolayer culture. Treatment with KJ-Pyr-9, a specific inhibitor of MYC/NMYC-myc-associated factor X interaction, decreased survival by the induction of apoptosis of both. In summary, here, we present the novel colorectal cancer cell lines BKZ-2 and BKZ-3 as promising cellular in vitro models for colorectal carcinomas and identify the MYC/NMYC molecular pathway involved in CSC-induced carcinogenesis with relevant therapeutic potential.

Abuhamad A, Syahir A. Understanding Glioblastoma Biomarkers: Knocking a Mountain with a Hammer

Gliomas are the most frequent and deadly form of human primary brain tumors. Among them, the most common and aggressive type is the high-grade glioblastoma multiforme (GBM), which rapidly grows and renders patients a very poor prognosis. Meanwhile, cancer stem cells (CSCs) have been determined in gliomas and play vital roles in driving tumor growth due to their competency in self-renewal and proliferation. Studies of gliomas have recognized CSCs via specific markers. This review comprehensively examines the current knowledge of the most significant CSCs markers in gliomas in general and in glioblastoma in particular and specifically focuses on their outlook and importance in gliomas CSCs research. We suggest that CSCs should be the superior therapeutic approach by directly targeting the markers. In addition, we highlight the association of these markers with each other in relation to their cascading pathways, and interactions with functional miRNAs, providing the role of the networks axes in glioblastoma signaling pathways.

The Clinical and Molecular Characteristics of Sex-Determining Region Y-Box 2 and its Prognostic Value in Breast Cancer: A Systematic Meta-Analysis

Objective

Transcription factor SOX2 (sex-determining region Y-box 2) has a crucial role in the maintenance of the stem cell state. However, current evidence regarding the role of SOX2 in breast cancer is conflicting. We conducted this meta-analysis to clarify the association of SOX2 expression with clinical and molecular features and its prognostic effect on breast cancer.

Methods

All relevant articles were searched using electronic databases. The pooled odds ratios (ORs) or hazard ratios (HRs: multivariate Cox survival analysis) with their 95% confidence intervals (CIs) were calculated.

Results

A final total of 18 studies containing 3,080 patients with breast cancer were included. SOX2 protein expression was not related to age, menopausal status, lymph node metastasis, lymphovascular invasion, molecular estrogen receptor status, progesterone receptor status, triple-negative status, and the overall survival in breast cancer, but was closely associated with advanced tumor grade (grade 3 vs. grade 1-2: OR = 2.74, 95% CI = 1.85-4.06, p < 0.001), clinical stage (stage 3-4 vs. stage 0-2: OR = 2.46, 95% CI = 1.37-4.40, p = 0.002), pT stage (T stage 2-4 vs. T stage 1: OR = 1.52, 95% CI = 1.07-2.17, p = 0.019), molecular human epidermal growth factor receptor 2 (HER2) status (positive vs. negative: OR = 1.61, 95% CI = 1.21-2.14, p = 0.001), epidermal growth factor receptor (EGFR) status (positive vs. negative: OR = 2.21, 95% CI = 1.13-4.33, p = 0.021), and worse disease-free survival (DFS) (HR = 2.66, 95% CI = 1.20-5.91, p = 0.016) of breast cancer.

Conclusions

SOX2 expression is correlated with breast cancer progression, HER2 status, and EGFR status, and may be an independent prognostic marker for predicting poor DFS.

Nanomedicine in osteosarcoma therapy: Micelleplexes for delivery of nucleic acids and drugs toward osteosarcoma-targeted therapies

Osteosarcoma(OS) represents the main cancer affecting bone tissue, and one of the most frequent in children. In this review we discuss the major pathological hallmarks of this pathology, its current therapeutics, new active biomolecules, as well as the nanotechnology outbreak applied to the development of innovative strategies for selective OS targeting. Small RNA molecules play a role as key-regulator molecules capable of orchestrate different responses in what concerns cancer initiation, proliferation, migration and invasiveness. Frequently associated with lung metastasis, new strategies are urgent to upgrade the therapeutic outcomes and the life-expectancy prospects. Hence, the prominent rise of micelleplexes as multifaceted and efficient structures for nucleic acid delivery and selective drug targeting is revisited here with special emphasis on ligand-mediated active targeting. Future landmarks toward the development of novel nanostrategies for both OS diagnosis and OS therapy improvements are also discussed.

Clinical Significance of Cancer Stem Cell Markers CD133 and CXCR4 in Osteosarcomas

Objective:

Osteosarcomas (OS) is one the most common primary bone malignancy in humans with the lungs metastasis in most cases. Metastasis and recurrence of OS is attributed to cancer stem cells (CSCs). Our study aimed to evaluate the clinical significance of CD133 and C-X-C chemokine receptor type 4 (CXCR4) as the frequently applied markers for CSCs in OS patients.

Methods:

In this cross-sectional, a total of 50 tissue samples from the patients with primary OS were immunohistochemically examined to detect the expression of CD133 and CXCR4. The associations of the relative expression and clinical significance of each marker were also evaluated.

Results:

High level expression of CD133 was detected in 26% of OS patient tissues. Of the 12 patients who showed lung metastasis, 5 cases showed high expression of CD133 with marginal trend correlation (P=0.06). No significant correlation was observed between CD133 expression and clinicopathological factors. Only 36% of cases showed CXCR4 expression which was not significantly correlated with gender, age, tumor size, necrosis, stage and metastasis (P>0.05). Clinically, patients with concomitant CD133/CXCR4 expression had significant association with lung metastasis (P=0.05).

Conclusion:

Our findings showed that concomitant expression of CSC markers CD133/CXCR4 might had a synergistic effect on the OS poor prognosis. These markers could be considered as potential therapeutic candidates of OS targeted therapy.

Immunohistochemical Expression of CD133 and LGR5 in Ulcerative Colitis-associated Colorectal Cancer and Dysplasia

BACKGROUND/AIM

Cluster of differentiation 133 (CD133) and leu cine-rich orphan G-protein-coupled receptor 5 (LGR5) are the most putative stem cell markers for colorectal cancer (CRC), and are associated with poor prognosis of patients with CRC. However, the role of CD133 and LGR5 in the inflammation-dysplasia-carcinoma sequence has not been fully elucidated. We examined the expression of CD133 and LGR5 in ulcerative colitis-associated CRC (UC-CRC; n=20) and UC-associated colorectal dysplasia (n=16) by immunohistochemistry.

RESULTS

The rate of CD133-positive cases in UC-CRC was significantly higher than that in dysplasia (p=0.026), but that of LGR5 expression was not. Moreover, LGR5 expression was significantly positively associated with p53 expression (p=0.03), whereas CD133 expression positively correlated with p53 expression, but not significantly (p=0.10).

CONCLUSION

CD133 may play an important role in tumor development in the context of the inflammation-dysplasia-carcinoma sequence. LGR5-positive cancer stem cells may play a critical role in the development of UC-CRC, particularly upon loss of p53 function.

Colorectal cancer stem cells properties and features: evidence of interleukin-8 involvement

Colorectal cancer (CRC) still remains a disease with high percentage of death, principally due to therapy resistance and metastasis. During the time the hypothesis has been reinforced that CRC stem cells (CRCSC) are involved in allowing intratumoral heterogeneity, drug escape mechanisms and secondary tumors. CRCSC are characterized by specific surface markers (i.e., CD44 and CD133), signaling pathways activation (i.e., Wnt and Notch) and gene expression (i.e., Oct4 and Snail), which confer to CRCSC self-renewal abilities and pluripotent capacity. Interleukin (IL)-8 is correlated to CRC progression, development of liver metastases and chemoresistance; moreover, IL-8 modulates not only stemness maintenance but also stemness promotion, such as epithelial-mesenchymal transition. This review wants to give a brief and up-to-date overview on IL-8 implication in CRCSC cues.

CD133: An emerging prognostic factor and therapeutic target in colorectal cancer

Colorectal cancer (CRC) is one of the leading causes of death worldwide. Recently, the role of cancer stem cells (CSCs) has been highlighted as a crucial emerging factor in chemoresistance, cancer relapse, and metastasis. CD133 is a surface marker of CSCs and has been argued to have prognostic and therapeutic values in CRC along with its related pathways such as Wnt, Notch, and hedgehog. Several studies have successfully applied targeted therapies against CD133 in CRC models namely bispecific antibodies (BiAbs) and anti-Wnt and notch pathways agents. These studies have yielded initial promising results in this regard. However, none of the therapeutics have been used in the clinical setting and their efficacy and adverse effects profile are yet to be elucidated. This review aims to gather the old and most recent data on the prognostic and therapeutic values of CD133 and CD133-targeted therapies in CRC.

Emerging insights into the biology of metastasis: A review article

Metastasis means the dissemination of the cancer cells from one organ to another which is not directly connected to the primary site. Metastasis has a crucial role in the prognosis of cancer patients. A few theories, different types of cell and several molecular pathways have been proposed to explain the mechanism of metastasis. In this work, the related articles in the limited period of time, 2000-mid -2018 were reviewed, through search in PubMed, Google Scholar and Scopus database. The articles published in the last two decades related to the biology of cancer metastasis were selected and the most important factors were discussed. Metastasis is critical factor to predict survival in patients with advanced cancer and prognosis determines the treatment plan. Many different cell types and various signaling pathways control the metastatic process. Metastasis is a multistep process. Many signaling pathways and molecules are involved in metastasis. Increasing knowledge about the mechanism of metastasis can help in finding the promising targets of cancer therapy.

New emerging roles of CD133 in cancer stem cell: Signaling pathway and miRNA regulation

Cancer stem cells (CSC) are rare immortal cells within a tumor that are able to initiate tumor progression, development, and resistance. Advances studies show that, like normal stem cells, CSCs can be both self-renewed and given rise to many cell types, therefore form tumors. A number of cell surface markers, such as CD44, CD24, and CD133 are frequently used to identify CSCs. CD133, a transmembrane glycoprotein, either alone or in collaboration with other markers, has been mainly considered to identify CSCs from different solid tumors. However, the exactness of CD133 as a cancer stem cell biomarker has not been approved yet. The clinical importance of CD133 is as a CSC marker in many cancers. Also, it contributes to shorter survival, tumor progression, and tumor recurrence. The expression of CD133 is controlled by many extracellular or intracellular factors, such as tumor microenvironment, epigenetic factors, signaling pathways, and miRNAs. In this study, it was attempted to determine: 1) CD133 function; 2) the role of CD133 in cancer; 3) CD133 regulation; 4) the therapeutic role of CD133 in cancers.

Delivery of Anti-miRNA for Triple-Negative Breast Cancer Therapy Using RNA Nanoparticles Targeting Stem Cell Marker CD133

Triple-negative breast cancer (TNBC) is an aggressive disease with a short median time from relapse to death. The increased aggressiveness, drug resistance, disease relapse, and metastasis are associated with the presence of stem cells within tumors. Several stem cell markers, such as CD24, CD44, CD133, ALDH1, and ABCG2, have been reported, but their roles in breast cancer tumorigenesis remain unclear. Herein, we apply RNA nanotechnology to deliver anti-microRNA (miRNA) for TNBC therapy. The thermodynamically and chemically stable three-way junction (3WJ) motif was utilized as the scaffold to carry an RNA aptamer binding to CD133 receptor and a locked nuclei acid (LNA) sequence for miRNA21 inhibition. Binding assays revealed the specific uptake of the nanoparticles to breast cancer stem cells (BCSCs) and TNBC cells. Functional assays showed that cancer cell migration was reduced, miR21 expression was inhibited, and downstream tumor suppressor PTEN and PDCD4 expressions were upregulated. In vitro and in vivo studies revealed that these therapeutic RNA nanoparticles did not induce cytokine secretion. Systemic injection of these RNA nanoparticles in animal trial demonstrated high specificity in TNBC tumor targeting and high efficacy for tumor growth inhibition. These results revealed the clinical translation potential of these RNA nanoparticles for TNBC therapy.

DCLK1 Expression in Colorectal Polyps Increases with the Severity of Dysplasia

BACKGROUND

The expression of doublecortin-like kinase 1 (DCLK1) has been investigated in cancer; however not in precancerous adenomatous polyps.

MATERIALS AND METHODS

Immunohistological expression of DCLK1 was evaluated in various grades of adenomas, cancerous polyps, and hyperplastic polyps in resected human tissue specimens.

RESULTS

Ninety-two specimens were positive for DCLK1 and 134 were negative. Cancerous polyps showed a high DCLK1 positivity rate compared to adenomas (68.4% vs. 36.8%; p<0.01). The rate of DCLK1 positivity was not significantly different among the three grades of adenomas (mild, moderate, and severe). DCLK1 was highly positive in advanced adenomas than low risk adenomas (49.6% vs. 29.3%; p<0.01).

CONCLUSION

The expression of DCLK1 was found in low-grade adenomas and increased with worsening severity of dysplasia. DCLK1 expression was highly observed in advanced adenomas, which had a clinically higher malignant potential.

Cancer stem cells in progression of colorectal cancer

Colorectal cancer is one of the most common cancers worldwide with high mortality. Distant metastasis and relapse are major causes of patient death. Cancer stem cells (CSCs) play a critical role in the metastasis and relapse of colorectal cancer. CSCs are a subpopulation of cancer cells with unique properties of self-renewal, infinite division and multi-directional differentiation potential. Colorectal CSCs are defined with a group of cell surface markers, such as CD44, CD133, CD24, EpCAM, LGR5 and ALDH. They are highly tumorigenic, chemoresistant and radioresistant and thus are critical in the metastasis and recurrence of colorectal cancer and disease-free survival. This review article updates the colorectal CSCs with a focus on their role in tumor initiation, progression, drug resistance and tumor relapse.

Establishment of CMab-43, a Sensitive and Specific Anti-CD133 Monoclonal Antibody, for Immunohistochemistry

CD133, also known as prominin-1, was first described as a cell surface marker on early progenitor and hematopoietic stem cells. It is a five-domain transmembrane protein composed of an N-terminal extracellular tail, two small cytoplasmic loops, two large extracellular loops containing seven potential glycosylation sites, and a short C-terminal intracellular tail. CD133 has been used as a marker to identify cancer stem cells derived from primary solid tumors and as a prognostic marker of gliomas. Herein, we developed novel anti-CD133 monoclonal antibodies (mAbs) and characterized their efficacy in flow cytometry, Western blot, and immunohistochemical analyses. We expressed the full length of CD133 in LN229 glioblastoma cells, immunized mice with LN229/CD133 cells, and performed the first screening using flow cytometry. After limiting dilution, we established 100 anti-CD133 mAbs, reacting with LN229/CD133 cells but not with LN229 cells. Subsequently, we performed the second and third screening with Western blot and immunohistochemical analyses, respectively. Among 100 mAbs, 11 strongly reacted with CD133 in Western blot analysis. One of 11 clones, CMab-43 (IgG_2a, kappa), showed a sensitive and specific reaction against colon cancer cells, warranting the use of CMab-43 in detecting CD133 in pathological analyses of CD133-expressing cancers.