Potential Cancer Stem Cell Marker Research Articles

CD133+/ABCC5+ cervical cancer cells exhibit cancer stem cell properties

ObjectiveThis study explores the correlation between Forkhead box M1 (FOXM1) and ATP-binding cassette subfamily C member 5 (ABCC5) in relation to paclitaxel resistance in cervical cancer. It aims to identify potential cervical cancer stem cell markers, offering fresh perspectives for developing therapeutic strategies to overcome paclitaxel chemoresistance in cervical cancer. MethodsPaclitaxel-resistant Hela cells (Hela/Taxol) were developed by intermittently exposing Hela cells to progressively increasing concentrations of paclitaxel. We assessed the biological properties of both Hela and Hela/Taxol cells using various assays: cell proliferation, clonogenic, cell cycle, apoptosis, scratch, and transwell. To determine which markers better represent tumor stem cells, we analyzed various known and potential stem cell markers in combination. Flow cytometry was employed to measure the proportion of positive markers in both parental and drug-resistant cell lines. Following statistical analysis to establish relative stability, CD133+ABCC5+ cells were sorted for further examination. Subsequent tests included sphere-forming assays and Western blot analysis to detect the presence of the stem cell-specific protein Sox2, aiding in the identification of viable cervical cancer stem cell markers. ResultsThe Hela/Taxol cell line exhibited significantly enhanced proliferation, migration, and invasion capabilities compared to the Hela cell line, alongside a marked reduction in apoptosis rates (P < 0.01). Notably, proportions of CD44+, CD24+CD44+, ABCC5+, CD24+CD44+ABCC5+, CD44+ABCC5+, CD24+CD44+FOXM1+, CD44+FOXM1+, CD133+ABCC5+, and CD133+FOXM1+ were significantly higher (P < 0.05). Furthermore, the size and number of spheres formed byCD133+ABCC5+ cells were greater in the sorted Hela/Taxol line (P < 0.01), with increased expression of the stem cell marker Sox2 (P < 0.001). ConclusionThe Hela/Taxol cells demonstrate increased tumoral stemness, suggesting that CD133+ABCC5+ may serve as a novel marker for cervical cancer stem cells.

Identification of a novel combination treatment strategy in clear cell renal cell carcinoma stem cells with shikonin and ipilimumab.

Management of clear cell renal cell carcinoma (ccRCC) has changed rapidly in recent years with the advent of immune checkpoint inhibitors (ICIs). However, only a limited number of patients can sustainably respond to immune checkpoint inhibitors and many patients develop resistance to therapy, creating an additional need for therapeutic strategies to improve the efficacy of systemic therapies. Binding probability and target genes prediction using online databases, invasion, migration, and apoptosis assays as well as the inhibition of cancer stem cells (CSCs) markers in ccRCC cell lines were used to select the most promising phytochemicals (PTCs). Mixed lymphocyte tumor cell culture (MLTC) system and flow cytometry were performed to confirm the potential combination strategy. The potential immunotherapeutic targets and novel CSC markers were identified via the NanoString analysis. The mRNA and protein expression, immune signatures as well as survival characteristics of the marker in ccRCC were analyzed via bioinformation analysis. Shikonin was selected as the most promising beneficial combination partner among 11 PTCs for ipilimumab for the treatment of ccRCC patients due to its strong inhibitory effect on CSCs, the significant reduction of FoxP3+ Treg cells in peripheral blood mononuclear cells (PBMCs) of patients and activation of the endogenous effector CD3+CD8+ and CD3+CD4+ T cells in response to the recognition of tumor specific antigens. Based on NanoString analysis VCAM1, CXCL1 and IL8 were explored as potential immunotherapeutic targets and novel CSC markers in ccRCC. The expression of VCAM1 was higher in the tumor tissue both at mRNA and protein levels in ccRCC compared with normal tissue, and was significantly positively correlated with immune signatures and survival characteristics in ccRCC patients. We propose that a combination of shikonin and ipilimumab could be a promising treatment strategy and VCAM1 a novel immunotherapeutic target for the treatment of ccRCC.

The clinical significance of CD44v6 in malignant and benign primary bone tumors

BackgroundThe objective of this study was to assess the expression profile of CD44v6, a potential cancer stem cell marker, and its diagnostic and predictive significance in three distinct types of primary bone tumors.MethodsIn this study, we utilized real-time qRT-PCR and immunohistochemistry to examine the gene and protein levels of CD44v6 in a total of 138 fresh bone tissues. This included 69 tumor tissues comprising osteosarcoma (N = 23), chondrosarcoma (N = 23), and GCT (N = 23), as well as 69 corresponding non-cancerous tumor margins. Furthermore, we investigated the circulating level of CD44v6 by isolating peripheral blood mononuclear cells from 92 blood samples. Among these, 69 samples were obtained from patients diagnosed with primary bone tumors, while the remaining 23 samples were from healthy donors. The primary objectives of our investigation were to assess the correlation between CD44v6 expression levels and clinic-pathological features of the patients, as well as to evaluate the diagnostic and predictive values of CD44v6 in this context.ResultsIn patients with osteosarcoma and chondrosarcoma tumors, both the gene and protein expression of CD44v6 were found to be significantly higher compared to the GCT group. Furthermore, the circulating level of CD44v6 was notably elevated in patients diagnosed with osteosarcoma and chondrosarcoma in comparison to the GCT group and patients with malignant tumor characteristics. Additionally, we observed a strong correlation between the gene and protein levels of CD44v6 and important tumor indicators such as tumor grade, metastasis, recurrence, and size at the tumor site. CD44v6 shows potential in differentiating patients with bone tumors from both control groups and tumor groups with severe and invasive characteristics from those with non-severe features. Importantly, the expression level of CD44v6 also demonstrated predictive value for determining tumor grade and the likelihood of recurrence.ConclusionCD44v6 is likely to play a role in the development of primary bone tumors and has the potential to serve as a diagnostic biomarker for bone cancer. However, to obtain more accurate and conclusive findings, further mechanistic investigations involving larger population samples are necessary.

Proportion of CD44+ Subset of Tumour Cells in Single Cell Suspension Prepared from FFPET Sections Directly Correlates with Histological Subtyping of Head and Neck Squamous Cell Carcinoma

CD44 expression in tumours imparts potential to progress, metastasize, recurrence, and resistance against antineoplastic therapy. In this study, we sought to describe the variation in the immuno-expression and numeration of MDR1+ and CD44+ potential cancer stem cells in different histological grades and subtypes of head and neck squamous cell carcinoma (HNSCC). Flow-cytometric analysis was performed on single cell suspension prepared from formalin fixed paraffin embedded tissue (FFPET) sections of HNSCC using anti-CD44 and anti-MDR1/ABCB-1 primary monoclonal antibodies. Immunohistochemical (IHC) staining was also carried out using both of these antibodies on HNSCC tissue sections mounted on super frosted glass slides. On immunohistochemical analysis, the mean IRS for CD44 and MDR1 were 8.6364 ±3.02114 and 1.5909 ±1.27674 respectively. When mean immune-expression scores of CD44 antibody and MDR1/ABCB-1 were compared with histological grades and subtypes of HNSCC, the relationship was found to be statistically insignificant. Interestingly, a strong statistical difference (p = 0.000) was observed when the mean score of subset of dysplastic squamous epithelial cells with characteristics of cell stemness (CD326+CD44+) was compared among different histological subtypes of HNSCC using flowcytometric analysis. While no statistically significant association was observed when the mean score for subset of dysplastic cells with potential of drug resistance (CD44+MDR1+) was compared among different histological subtypes of HNSCC. Although potential cancer stem cell marker CD44 and the multidrug resistance maker ABCB-1/MDR1 co-expressed in HNSCC but the proportion of CD326+CD44+ subset of tumour cells (potential cancer stem cells/CSCs) significantly correlates with least aggressive to more aggressive tumour subtypes.

Lung Cancer Stem Cell Markers as Therapeutic Targets: An Update on Signaling Pathways and Therapies.

Cancer stem cells, a relatively small group of self-renewing cancer cells, were first isolated from acute myeloid leukemia. These cells can play a crucial role in tumor metastasis, relapse, and therapy resistance. The cancer stem cell theory may be applied to lung cancer and explain the inefficiency of traditional treatments and eventual recurrence. However, because of the unclear accuracy and illusive biological function of cancer stem cells, some researchers remain cautious about this theory. Despite the ongoing controversy, cancer stem cells are still being investigated, and their biomarkers are being discovered for application in cancer diagnosis, targeted therapy, and prognosis prediction. Potential lung cancer stem cell markers mainly include surface biomarkers such as CD44, CD133, epithelial cell adhesion molecule, and ATP-binding cassette subfamily G member 2, along with intracellular biomarkers such as aldehyde dehydrogenase, sex-determining region Y-box 2, NANOG, and octamer-binding transcription factor 4. These markers have different structures and functions but are closely associated with the stem potential and uncontrollable proliferation of tumor cells. The aberrant activation of major signaling pathways, such as Notch, Hedgehog, and Wnt, may be associated with the expression and regulation of certain lung cancer stem cell markers, thus leading to lung cancer stem cell maintenance, chemotherapy resistance, and cancer promotion. Treatments targeting lung cancer stem cell markers, including antibody drugs, nanoparticle drugs, chimeric antigen receptor T-cell therapy, and other natural or synthetic specific inhibitors, may provide new hope for patients who are resistant to conventional lung cancer therapies. This review provides comprehensive and updated data on lung cancer stem cell markers with regard to their structures, functions, signaling pathways, and promising therapeutic target approaches, aiming to elucidate potential new therapies for lung cancer.

Update on Glycosphingolipids Abundance in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the most frequent type of primary liver cancer. Low numbers of HCC patients being suitable for liver resection or transplantation and multidrug resistance development during pharmacotherapy leads to high death rates for HCC patients. Understanding the molecular mechanisms of HCC etiology may contribute to the development of novel therapeutic strategies for prevention and treatment of HCC. UDP-glucose ceramide glycosyltransferase (UGCG), a key enzyme in glycosphingolipid metabolism, generates glucosylceramide (GlcCer), which is the precursor for all glycosphingolipids (GSLs). Since UGCG gene expression is altered in 0.8% of HCC tumors, GSLs may play a role in cellular processes in liver cancer cells. Here, we discuss the current literature about GSLs and their abundance in normal liver cells, Gaucher disease and HCC. Furthermore, we review the involvement of UGCG/GlcCer in multidrug resistance development, globosides as a potential prognostic marker for HCC, gangliosides as a potential liver cancer stem cell marker, and the role of sulfatides in tumor metastasis. Only a limited number of molecular mechanisms executed by GSLs in HCC are known, which we summarize here briefly. Overall, the role GSLs play in HCC progression and their ability to serve as biomarkers or prognostic indicators for HCC, requires further investigation.

Evaluation of correlation between CD44, radiotherapy response, and survival rate in patients with advanced stage of head and neck squamous cell carcinoma (HNSCC).

PurposeCancer stem cells (CSCs) constitute a distinctive subpopulation of cancer cells that are competent in tumor initiation, invasion, recurrence, and resistance to chemoradiotherapy. CD44, a hyaluronic acid (HA) receptor has been considered as a potential CSC marker in head and neck cancer. The purpose of this study is to evaluate the correlation between CD44 and clinicopathological parameters, treatment response, survival, and recurrence.MethodsThe CD44 expression was examined by immunohistochemistry (IHC) in 90 samples of head and neck squamous cell carcinoma (HNSCC) confirmed patients. The expression of CD44 and its association with clinicopathological parameters, treatment response, and survival was determined.ResultsIn all HNSCC patient samples, CD44 was expressed consistently at different intensities. Tumor size (p < 0.001), stage (p < 0.001), and treatment response (p < 0.001) showed statistically significant association with CD44 expression. Alcohol and CD44 were observed as independent predictors of response to radiotherapy using multivariate ordinal logistic regression analysis. Analysis of 2‐year overall survival (OS) showed that CD44 expression (p = 0.02), tumor size (p = 0.001), lymph node status (p < 0.001), stage (p < 0.001), and grade (p = 0.007) were significantly associated with OS. Using Cox regression analysis, lymph node status (p = 0.001), grade (p < 0.001), recurrence (p < 0.001), and CD44 expression (p = 0.003) were found to be potential independent predictors of OS.ConclusionOur findings suggest that CD44 contributes to resistance to radiotherapy and poor OS. The results also suggest that except for CD44 there could be other factors such as lymph node metastasis, grade, and alcohol which should be investigated as potential targets for therapy.

FUS-DDIT3 Fusion Oncoprotein Expression Affects JAK-STAT Signaling in Myxoid Liposarcoma.

Myxoid liposarcoma is one of the most common sarcoma entities characterized by FET fusion oncogenes. Despite a generally favorable prognosis of myxoid liposarcoma, chemotherapy resistance remains a clinical problem. This cancer stem cell property is associated with JAK-STAT signaling, but the link to the myxoid-liposarcoma-specific FET fusion oncogene FUS-DDIT3 is not known. Here, we show that ectopic expression of FUS-DDIT3 resulted in elevated levels of STAT3 and phosphorylated STAT3. RNA sequencing identified 126 genes that were regulated by both FUS-DDIT3 expression and JAK1/2 inhibition using ruxolitinib. Sixty-six of these genes were connected in a protein interaction network. Fifty-three and 29 of these genes were confirmed as FUS-DDIT3 and STAT3 targets, respectively, using public chromatin immunoprecipitation sequencing data sets. Enriched gene sets among the 126 regulated genes included processes related to cytokine signaling, adipocytokine signaling, and chromatin remodeling. We validated CD44 as a target gene of JAK1/2 inhibition and as a potential cancer stem cell marker in myxoid liposarcoma. Finally, we showed that FUS-DDIT3 interacted with phosphorylated STAT3 in association with subunits of the SWI/SNF chromatin remodeling complex and PRC2 repressive complex. Our data show that the function of FUS-DDIT3 is closely connected to JAK-STAT signaling. Detailed deciphering of molecular mechanisms behind tumor progression opens up new avenues for targeted therapies in sarcomas and leukemia characterized by FET fusion oncogenes.

Lung Adenocarcinoma Mouse Models Based on Orthotopic Transplantation of Syngeneic Tumor-Initiating Cells Expressing EpCAM, SCA-1, and Ly6d.

Simple SummaryLung cancer is the leading cause of cancer deaths worldwide and lung adenocarcinoma (LUAD) is the most common type of lung cancer. To better understand the relation between genetic alterations and the characteristics of lung cancer as well as the interactions between tumor cells and components of the tumor microenvironment, we have developed organoid-based orthotopic and syngeneic mouse models of LUAD driven by the KRASG12V or EML4-ALK oncogene. These models formed tumors closely recapitulating the pathology of human LUAD and proved useful tools for in vitro and in vivo drug efficacy studies. In addition, with the use of these models, we identified Ly6d as a potential novel cancer stem cell marker for LUAD. Given their clinical relevance, our mouse models are important tools for studying cancer stem cell biology and LUAD drug development.Somatic mutations in EGFR and KRAS as well as chromosome rearrangements affecting ALK, ROS1, and RET have been identified in human lung adenocarcinoma (LUAD). We here developed organoid-based orthotopic and syngeneic mouse models for studies of the pathogenesis and treatment of LUAD. We isolated EpCAM-positive epithelial cells from mouse lungs and cultured them as organoids to maintain epithelial stem cell properties. These cells were transformed by KRAS(G12V) or EML4-ALK and then transplanted via the trachea into the lungs of the syngeneic mice, where they formed tumors that expressed the lung lineage marker TTF-1 and which closely recapitulated the pathology of human LUAD. Treatment with crizotinib suppressed the growth of tumors formed by the EML4-ALK–expressing lung epithelial cells in a subcutaneous transplantation model. Organoid culture of normal lung epithelial cells resulted in enrichment of EpCAM+SCA-1(Ly6a)+ cells as well as in that of cells expressing another member of the Ly6 protein family, Ly6d, which was found to be required for the growth of the LUAD-initiating cells expressing KRAS(G12V) or EML4-ALK. We also found that a high expression level of LY6D was associated with poor prognosis in human LUAD. Our results thus suggest that LY6D is a potential lung cancer stem cell marker.

Role of doublecortin-like kinase 1 and leucine-rich repeat-containing G-protein-coupled receptor 5 in patients with stage II/III colorectal cancer: Cancer progression and prognosis.

BACKGROUNDCancer stem cells (CSCs) are a subpopulation of cancer cells with the potential of self-renewal and differentiation. CSCs play critical roles in tumorigenesis, recurrence, metastasis, radiation tolerance and chemoresistance.AIMTo assess the expression patterns and clinical potential of doublecortin-like kinase 1 (DCLK1) and leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5), as prognostic CSC markers of colorectal cancer (CRC). METHODSThe expression of DCLK1 and Lgr5 in CRC tissue sections from 92 patients was determined by immunohistochemistry. Each case was evaluated using a combined scoring method based on signal intensity staining (scored 0-3) and the proportion of positively stained cancer cells (scored 0-3). The final staining score was calculated as the intensity score multiplied by the proportion score. Low expression of DCLK1 and Lgr5 was defined as a score of 0-3; high expression of DCLK1 and Lgr5 was defined as a score of ≥ 4. Specimens were categorized as either high or low expression, and the correlation between the expression of DCLK1 or Lgr5 and clinicopathological factors was investigated.RESULTSDCLK1 and Lgr5 expression levels were significantly positively correlated. CRC patients with high DCLK1, Lgr5 and DCLK1/Lgr5 expressions had poorer progression-free survival and overall survival. Moreover, high expression of DCLK1 was an independent prognostic factor for recurrence and overall survival in patients with CRC by multivariate analysis (P = 0.026 and P = 0.049, respectively).CONCLUSIONDCLK1 may be a potential CSC marker for the recurrence and survival of CRC patients.

Expression patterns and clinical significance of the potential cancer stem cell markers OCT4 and NANOG in colorectal cancer patients

ABSTRACT Colorectal cancer (CRC) is one of the most important malignancies and causes of cancer-related deaths worldwide. Cancer stem cell markers identification could be helpful to acquire important prognostic information and develop new treatment regimens. This study aimed to evaluate the expression of OCT4 and NANOG in CRC patients and their clinical significance. Totally 359 CRC samples were stained for OCT4 and NANOG expression using tissue microarray. The correlation between their expression and clinical and pathological features was explored. The majority of CRC cases showed low-level expression of OCT4 (80%) and NANOG (75%). Lower expression of OCT4 was more often detected in CRC cases with no vascular involvement (P = .01). Also, a trend found between low level of OCT4 expression and absence of distant metastasis or lymph node involvement (P = .07 and P = .09, respectively). Surprisingly, a significant positive correlation was observed between NANOG expression and cellular differentiation (P = .05). Our combined analysis demonstrated that OCT4 low/NANOG low phenotype has frequently seen in colorectal cancer cases with no vascular invasion (P = .05). Our observations indicated that higher expression of OCT4 and NANOG can confer malignant and aggressive behavior to CRC. Evaluation of the co-expression of these cancer stem cell markers can serve a new diagnostic and prognostic approach in CRC patients. These findings also suggested that simultaneous expression of OCT4 and NANOG can be considered as a therapeutic marker for targeted therapy of CRC, especially in advanced stages.

Cancer Stem Cells of Diffuse Large B Cell Lymphoma Are Not Enriched in the CD45+CD19- cells but in the ALDHhigh Cells.

Although the existence of cancer stem cells (CSCs) has been suggested in diffuse large B cell lymphoma (DLBCL), there is still no definitive marker. CD45+CD19- has been regarded as a potential marker of CSCs in mantle cell lymphoma (MCL). So, we explored the role of CD45+CD19- in DLBCL. However, both CD45+CD19- cells and CD45+CD19+ cells did not generate tumors until more than 100,000 cells were inoculated in NOD/SCID mice, even CD45+CD19+ cells generated more and larger tumors, as well as the soft agar colony formation in vitro; The aldehyde dehydrogenase (ALDH) activity was also identified in this study. Only 1,500 ALDHhigh cells were enough to generate tumors in mice while the same number of ALDH- cells were not. Moreover, both groups formed tumors when more cells were inoculated, but ALDHhigh cells formed more and larger tumors. The similar result was obtained in vitro clonogenicity experiments. OCT4, SOX2, Nanog, and ABCG2 genes did not show any difference in CD45+CD19+, CD45+CD19-, ALDHhigh and ALDH- cells. Taken together, CSCs are not enriched in the CD45+CD19- cells but in the ALDHhigh cells in DLBCL cell lines.

Characterization of CD44-positive Cancer Stem-like Cells in COLO 201 Cells.

Cancer stem cells (CSCs) are considered to be one of the causes of tumor recurrence after chemotherapy. The purpose of our study was to isolate CSCs from human colorectal cancer cell (CRC) lines. Nine CRC lines were screened based on the expression level of potential CSC markers to identify putative CSCs. Tumor formation capacity in immunodeficient mice was compared with that of their counterparts. Stemness, differentiation potency and sensitivity to 5-fluorouracil (5-FU), in vitro, were also assessed. Microarray analysis was used to characterize the features of the putative CSCs. COLO 201 cells were separated into two populations based on CD44 expression. CD44 positive (CD44+) cells showed significantly higher tumor formation capacity than CD44- cells in immunodeficient mice. CD44+ cells also possessed stemness properties and lower sensitivity to 5-FU in vitro. Moreover, cancer stemness and chemoresistance-related genes were highly up-regulated in CD44+ cells. CD44+ COLO 201 cells possessed the features of CSCs; therefore, the present CSC model could serve as a valuable tool to accelerate CSC research.

Integrin α7 correlates with worse clinical features and prognosis, and its knockdown inhibits cell proliferation and stemness in tongue squamous cell carcinoma.

The present study aimed to evaluate the correlation of integrin α7 (ITGA7) with clinicopathological characteristics and overall survival (OS) in patients with tongue squamous cell carcinoma (TSCC), and to investigate the effect of ITGA7 knockdown on proliferation, apoptosis and stemness of TSCC cells in vitro. ITGA7 expression was measured in tumor tissues and paired adjacent normal tissues from 60 patients with TSCC using immunohistochemistry. ITGA7 expression in human TSCC cell lines and normal oral keratinocytes was measured using quantitative PCR and western blotting. Lentiviruses carrying short hairpin (sh) RNA targeting ITGA7 were used to knockdown its expression in CAL-27 and HSC-4 cells, and then proliferation, apoptosis and stemness were measured. In addition, CAL-27 and HSC-4 cancer stem cells (CSCs) were constructed and their ITGA7 expression was measured. The results demonstrated that ITGA7 was upregulated in the tumor tissues compared with the paired adjacent tissues, and its high expression was correlated with worse pathological grade, N stage, TNM stage and OS. In vitro, ITGA7 expression levels were demonstrated to be increased in the TSCC CAL-27, SCC-9, HSC-4 and SCC-25 cell lines compared to the normal HOK cell line. In CAL-27 and HSC-4 cells, ITGA7 knockdown inhibited cell proliferation, promoted apoptosis, increased CD24 expression, decreased CD44 and CD133 expression, reduced drug resistance to cisplatin and attenuated sphere formation efficiency. Finally, ITGA7 expression levels were greatly elevated in CAL-27 and HSC-4 CSCs compared with parental CAL-27 and HSC-4 cells. In conclusion, ITGA7 knockdown inhibited tumor cell proliferation and stemness in TSCC cells. These findings indicated that ITGA7 might serve as a potential marker for CSCs and may correlate with worse clinical features and prognosis in TSCC.

Identification of Breast Cancer Stem Cell Related Genes Using Functional Cellular Assays Combined With Single-Cell RNA Sequencing in MDA-MB-231 Cells.

Breast cancer tumors display different cellular phenotypes. A growing body of evidence points toward a population of cancer stem cells (CSCs) that is important for metastasis and treatment resistance, although the characteristics of these cells are incomplete. We used mammosphere formation assay and label-retention assay as functional cellular approaches to enrich for cells with different degree of CSC properties in the breast cancer cell line MDA-MB-231 and performed single-cell RNA sequencing. We clustered the cells based on their gene expression profiles and identified three subpopulations, including a CSC-like population. The cell clustering into these subpopulations overlapped with the cellular enrichment approach applied. To molecularly define these groups, we identified genes differentially expressed between the three subpopulations which could be matched to enriched gene sets. We also investigated the transition process from CSC-like cells into more differentiated cell states. In the CSC population we found 14 significantly upregulated genes. Some of these potential breast CSC markers are associated to reported stem cell properties and clinical survival data, but further experimental validation is needed to confirm their cellular functions. Detailed characterization of CSCs improve our understanding of mechanisms for tumor progression and contribute to the identification of new treatment targets.

Increased expression of DCLK1, a novel putative CSC maker, is associated with tumor aggressiveness and worse disease-specific survival in patients with bladder carcinomas

Doublecortin-like kinase 1 (DCLK1) has been characterized as a novel potential cancer stem cell (CSC) marker in several types of cancer. It is considered as one of the most specific markers for distinguishing colorectal CSCs from normal stem cells. Yet, there are limited reports on the role of DCLK1 as a putative CSC marker in bladder cancer. Using immunohistochemistry, DCLK1 expression was examined in a well-defined tissue microarray series of 472 bladder cancer tissues. The association between DCLK1 protein expression and clinicopathological features, as well as survival outcomes, was assessed. Our findings showed strong, moderate, and weak DCLK1 expression in 123 (26.1%), 230 (48.7%), and 119 (25.2%) of the bladder cancer specimens, respectively. Higher expression of DCLK1 was significantly associated with increase in histological grade (P ≤ .001), pT stage (P = .014), lamina propria (P = .006), and lamina propria/muscularis (L/M) involvement (P = .014). On multivariate analysis, pT stage (P < .001), histological grade (P = .021), and lamina propria involvement (P = .001) were independent prognostic factors in DCLK1 expression. Moreover, the expression of DCLK1 was found to be an independent marker of poor prognosis for disease- specific survival (DSS) (P = .048) in bladder carcinomas. Our observations showed that DCLK1 expression was associated with more aggressive tumor behavior, more advanced disease, and poorer DSS in patients with bladder carcinomas. However, any potential clinical applications of DCLK1 as a novel target molecule in bladder cancer patients would require further investigations.

Characterization of OCT3/4, Nestin, NANOG, CD44 and CD24 as stem cell markers in canine prostate cancer.

The cancer cell population is heterogeneous, and cancer stem cells (CSCs) are important for tumor growth and maintenance. The CSC population is associated with different neoplastic characteristics, such as cell migration, resistance to apoptosis, radiation therapy and chemotherapy. To increase the knowledge of CSCs in canine prostate cancer (PC), we characterized CSC markers in canine PC tissues and tumorspheres. We performed immunohistochemistry of OCT3/4, Nestin, NANOG, CD44 and CD24 in 10 normal canine prostatic tissue samples, 10 prostatic hyperplastic (PH) tissue samples and 28 PC tissue samples. Then, we established two canine prostate cancer cell cultures and characterized the CSC profile of tumorspheres grown from these cultures. Normal and PH tissues were positive for Nestin, NANOG, CD44 and CD24 only in the basal cell layer. OCT3/4 was expressed in the luminal cells of normal and PH tissues. There was no significant difference in Nestin expression among the prostatic tissues. However, we found higher expression of NANOG and CD44 in canine PC tissues than that in normal and PH tissues. Tumorspheres from canine prostate cancer cells express OCT3/4, Nestin, NANOG and CD44, indicating that these markers may be potential cancer stem cell markers in canine PC. The results obtained can be useful to better characterize the stem cell population in canine prostatic cancer and to guide future studies in comparative oncology.

Abstract 3052: Identification and characterization of DPPA2 as a potential cancer stem cell marker in hepatocellular carcinoma

Abstract Cancer stem cells (CSC) are a small subpopulation of tumor cells that share many properties with embryonic stem cells, including the ability to differentiate and self-renew. The study of stemness-associated genes might give us a hint on the tumorigenesis and tumor progression. By comparing the expression profiles of human embryonic stem cells (ESC), endoderm, liver progenitors, premature hepatocytes as well as two pairs of non-tumor and tumor tissues of hepatocellular carcinoma (HCC), we found that the gene Developmental Pluripotency Associated 2 (DPPA2) was highly expressed in the stage of ESC, and decreased dramatically along with development, suggesting its role as a stemness associated gene. Analysis of HCC clinical samples showed that elevated expression of DPPA2 was significantly associated with differentiation, TNM stage, the number of tumor nodules and thrombus, as well as poorer prognosis. Functional studies demonstrated that DPPA2 - overexpressed cells displayed enhanced stemness feature, increasing the ability of self-renewal, tumorigenicity and chemo-resistance. We also found that overexpression of DPPA2 could increase the expression of some cancer stem cell markers. RNA-sequencing results suggested that Wnt signaling was abnormally activated after DPPA2 overexpression. Our findings point to a new potential cancer stem cell marker which may provide an attractive therapeutic target for HCC patients. Citation Format: Dandan Yu, Qian Yan, Yu Zhang, Ling Guo, Chuanyue Wu, Xin-yuan Guan. Identification and characterization of DPPA2 as a potential cancer stem cell marker in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3052.

Abstract 260: Apigenin nanoparticle suppresses sphere formation in CD133+/ALDH1high prostate cancer stem cells through downregulation of stem cell markers

Abstract The recurrence of prostate cancer after definitive treatment(s) is thought to be due to the potential of rare cancer stem cells (CSCs) to withstand therapy and initiate tumor formation. CSCs are a subpopulation of cancer cells capable of self-renewal and plastic adaptation mediating tumorigenesis, metastasis, and therapy resistance. CSCs are associated with cancer progression and clinical outcome in cancer patients. In the present study, we isolated CSCs from various human prostate cancer 22Rv1, DU145 and PC-3 cells by applying selection of cluster of differentiation 133 cell surface marker and high ALDH1 activity (CD133+/ALDH1high). Next we aimed to identify CD133+/ALDH1high CSCs isolated from human prostate cancer cells and compare their profiles with non-CSCs as bulk counterparts of the population. Subsequently, the CSC population continued to grow in the three-dimensional multicellular spheroids. Differentiation investigated with stem cell-related genomic characteristics exhibited significant increase in genes viz. CD44, Nanog, β-catenin, c-Myc, SOX2 and Oct4 in CSCs at the message level. In further studies we determine the effect of natural plant flavone apigenin on CSC population. Apigenin is abundantly present in common fruits and vegetables and possess remarkable anticancer, anti-angiogenic and anti-metastatic properties. Apigenin loaded polyethylene glycol nanoparticles (Ap-NP) was characterized for particle size, morphology, zeta potential, drug release and encapsulation. Cellular entry and intracellular localization of Ap-NP were assessed by transmission electron microscopy. Treatment of CD133+/ALDH1high CSCs with Ap-NP inhibited cell viability and sphere formation at higher extent in time dependent manner, compared to the non-CSCs counterparts. Furthermore, Ap-NP exposure resulted in the downregulation of Nanog, β-catenin, c-Myc, SOX2 and Oct4 in the CSCs. Taken together, our study demonstrate overexpression of potential CSC markers and the ability to target these CSCs by the use of non-toxic agent apigenin killing this rare population that may lead to the total abolition of tumor recurrence and/or metastasis. Citation Format: Rajnee Kanwal, Sanjeev Shukla, Agata A. Exner, Andreas G. Tzakos, Sanjay Gupta. Apigenin nanoparticle suppresses sphere formation in CD133+/ALDH1high prostate cancer stem cells through downregulation of stem cell markers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 260.

MicroRNA and transcriptome analysis in periocular Sebaceous Gland Carcinoma

Sebaceous gland carcinoma (SGC) is a rare, but life-threatening condition with a predilection for the periocular region. Eyelid SGC can be broadly categorised into two subtypes, namely either nodular or pagetoid with the latter being more aggressive and requiring radical excision to save life. We have identified key altered microRNAs (miRNA) involved in SGC shared by both subtypes, hsa-miR-34a-5p and hsa-miR-16-5p. However, their gene targets BCL2 and MYC were differentially expressed with both overexpressed in pagetoid but unchanged in nodular suggesting different modes of action of these two miRNAs on BCL/MYC expression. Hsa-miR-150p is nodular-specifically overexpressed, and its target ZEB1 was significantly downregulated in nodular SGC suggesting a tumour suppressor role. Invasive pagetoid subtype demonstrated specific overexpression of hsa-miR-205 and downregulation of hsa-miR-199a. Correspondingly, miRNA gene targets, EZH2 (by hsa-miR-205) and CD44 (by hsa-miR-199a), were both overexpressed in pagetoid SGC. CD44 has been identified as a potential cancer stem cell marker in head and neck squamous cell carcinoma and its overexpression in pagetoid cells represents a novel treatment target. Aberrant miRNAs and their gene targets have been identified in both SGC subtypes, paving the way for better molecular understanding of these tumours and identifying new treatment targets.