Keratinocytes Isolated From Individual Cleft Lip/Palate Patients Display Variations in Their Differentiation Potential in vitro

To gain more understanding of the complex molecular processes underlying cleft lip/palate (CLP), we established a unique human cell bank, consisting of keratinocytes and corresponding fibroblasts from individual CLP patients as a new study tool. After their careful characterization, we used such patient-derived cell cultures as well as control keratinocytes for in vitro differentiation and proliferation assays. Foreskin-derived control cells as a group showed significant higher induction of the late differentiation markers Loricrin and Filaggrin than the group of CLP patients-derived keratinocytes. Additionally, we detected great variations between individual CLP keratinocyte cell cultures in regard to their potential to terminally differentiate as assessed by the induction of Loricrin and Filaggrin. Primary patient cell cultures that did not properly differentiate, exhibited high proliferation rates. Moreover, we could correlate the expression levels of transcription factor IRF6 to the ability of individual cell cultures to terminally differentiate. Using clinically relevant, patient-derived cells, our results suggest that some of the genetic predispositions causing CLP might also lead to deficiencies in keratinocyte differentiation manifested in in vitro assays.

Co-treatment of tumor cells with hyaluronan plus doxorubicin affects endothelial cell behavior independently of VEGF expression

Hyaluronan, the main glycosaminoglycan of extracellular matrices, is concentrated in tissues with high cell proliferation and migration rates. In cancer, hyaluronan expression is altered and it becomes fragmented into low-molecular-weight forms, affecting mechanisms associated with cell proliferation, invasion, angiogenesis and multidrug resistance. Here, we analyzed the effect of low-molecular-weight hyaluronan on the response of T lymphoma, osteosarcoma, and mammary adenocarcinoma cell lines to the antineoplastic drug doxorubicin, and whether co-treatment with hyaluronan and doxorubicin modified the behavior of endothelial cells. Our aim was to associate the hyaluronan-doxorubicin response with angiogenic alterations in these tumors. After hyaluronan and doxorubicin co-treatment, hyaluronan altered drug accumulation and modulated the expression of ATP-binding cassette transporters in T-cell lymphoma cells. In contrast, no changes in drug accumulation were observed in cells from solid tumors, indicating that hyaluronan might not affect drug efflux. However, when we evaluated the effect on angiogenic mechanisms, the supernatant from tumor cells treated with doxorubicin exhibited a pro-angiogenic effect on endothelial cells. Hyaluronan-doxorubicin co-treatment increased migration and vessel formation in endothelial cells. This effect was independent of vascular endothelial growth factor but related to fibroblast growth factor-2 expression. Besides, we observed a pro-angiogenic effect on endothelial cells during hyaluronan and doxorubicin co-treatment in the in vivo murine model of T-cell lymphoma. Our results demonstrate for the first time that hyaluronan is a potential modulator of doxorubicin response by mechanisms that involve not only drug efflux but also angiogenic processes, providing an adverse tumor stroma during chemotherapy.

MiRNA influences in mesenchymal stem cell commitment to neuroblast lineage development

Mesenchymal Stem Cells (MSCs) are widely used in therapeutic applications. Their plasticity and predisposition to differentiate into a variety of cell types, including those of the neuronal lineage, makes them ideal to study whether a selection of miRNAs may direct the differentiation of MSCs into neuroblasts or neuroblastoma to mature neurons. Following a short-listing, miR-107, 124 and 381 were selected as the most promising candidates for this differentiation. MSCs differentiated into cells of the neural lineage (Conditioned Cells) upon addition of conditioned medium (rich in microvesicles containing miRNAs) obtained from cultured SH-SY5Y neuroblastoma cells. Characterisation of stemness (including SOX2, OCT4, Nanog and HCG) and neural markers (including Nestin, MASH1, TUBB3 and NeuN1) provided insight regarding the neuronal state of each cell type. This was followed by transfection of the three miRNA antagonists and mimics, and quantification of their respective target genes. MiRNA target gene expression following transfection of MSCs with miRNA inhibitors and mimics demonstrated that these three miRNAs were not sufficient to induce differentiation. In conditioned cells the marginal changes in the miRNA target expression levels reflected potential for the modulation of intermediate neural progenitors and immature neuron cell types. Transfection of various combinations of miRNA inhibitors and/or mimics revealed more promise. Undoubtedly, a mix of biomolecules is being released by the SH-SY5Y in culture that induce MSCs to differentiate. Screening for those biomolecules acting synergistically with specific miRNAs will allow further combinatorial testing to elucidate the role of miRNA modulation.

Novel biomarkers in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths and the fifth most common cancer worldwide. Most of these patients are seen with advanced disease at the time of presentation. In spite of its high prevalence, there are not many therapeutic options available for patients with advanced-stage HCC. There is an urgent need for improving early detection and prognostication of patients with HCC. In addition, the development of new therapies targeting specific pathways involved in the pathogenesis of HCC should be a major goal for future research, with the objective of improving outcomes of patients with HCC. Biomarkers represent a relatively easy and noninvasive way to detect and estimate disease prognosis. In spite of the numerous efforts to find molecules as possible biomarkers, there is not a single ideal marker in HCC. Many new findings have shown promising results both in diagnosing and treating HCC. In this review, we summarized the most recent and relevant biomarkers in HCC.

Targeting glypican-4 overcomes 5-FU resistance and attenuates stem cell-like properties via suppression of Wnt/β-catenin pathway in pancreatic cancer cells

The existences of cancer stem cells in patients with pancreatic cancer are considered as pivotal factors contributing to chemoresistance and disease relapse. Glypican-4 (GPC4) is one of the members of the glypicans family, which underlies human congenital malformations and multiple diseases. However, its potential biological function in pancreatic cancer still remains elusive. In this study, we are the first to demonstrate that GPC4 was involved in 5-fluorouracil (5-FU) resistance and pancreatic cancer stemness through comprehensive bioinformatical analysis. Functional experiments showed that knockdown of GPC4 sensitized pancreatic cancer cells to 5-FU and attenuated stem cell-like properties. In terms of mechanism research, knockdown of GPC4 suppressed the activation of Wnt/β-catenin pathway and its downstream targets. Furthermore, the expression of GPC4 was significantly upregulated in pancreatic cancer tissues compared with normal tissues and remarkably correlated with patients' overall survival according to the data derived from the Cancer Genome Atlas database. Taken together, our results suggest that GPC4 is a key regulator in chemoresistance and pancreatic cancer stemness. Thus, targeting GPC4 may serve as a promising strategy for pancreatic cancer therapy.

The combination of aldehyde dehydrogenase 1 (ALDH1) and CD44 is associated with poor outcomes in endometrial cancer

Aldehyde dehydrogenase 1 (ALDH1) and CD44 have been established as biomarkers for predicting the survival of many types of cancer patients. This study evaluated the expression and clinical significance of these putative cancer-cell markers in a series of tumor samples from endometrial cancer (EC) patients using tissue microarray. We examined 245 endometrial samples, including 132 (53.87%) pre-malignancy lesions and 113 (46.12%) malignant endometrial lesions from biopsies or hysterectomies. We examined the expression of CD44 and ALDH1 in these samples using immunohistochemistry staining. Correlations in the relative expression of these markers with clinicopathological parameters were also assessed. A high level of expression of ALDH1 was found in 44.25% (50/113) of the endometrial cancer samples, which was significantly correlated with a poor overall survival rate (p = 0.035). High-level CD44 expression was found in 35.4% (40/113) of the cases and was also correlated with a poor overall survival rate (p = 0.035). A simultaneous high expression of both markers was correlated with an extremely poor overall survival (p = 0.013). Our results show that tumors with higher expressions of both ALDH1 and CD44 were related to a poorer overall survival rate among EC patients. The combination of ALDH1 and CD44 could be a promising marker for developing additional targeted therapy for severe endometrial cancers.

Hyaluronic acid shell and disulfide-crosslinked core micelles for in vivo targeted delivery of bortezomib for the treatment of multiple myeloma

Bortezomib (BTZ) provides one of the best treatments for multiple myeloma (MM). The efficacy of BTZ is, nevertheless, restricted by its fast clearance, low selectivity, and dose limiting toxicities. Here, we report on targeted BTZ therapy of MM in vivo by hyaluronic acid-shelled and core-disulfide-crosslinked biodegradable micelles (HA-CCMs) encapsulating lipophilized BTZ, bortezomib-pinanediol (BP). HA-CCMs loaded with 7.3 BTZ equiv. wt% exhibited a small size of 78 nm, good stability in 10% FBS, and glutathione-triggered drug release. MTT assays in CD44 positive LP-1 multiple myeloma cells revealed that BP encapsulated in HA-CCMs caused enhanced antiproliferative effect compared with free BP. Flow cytometry, confocal microscopy and MTT assays indicated BP-loaded HA-CCMs (HA-CCMs-BP) could actively target to LP-1 cells and induce high antitumor effect. Proteasome activity assays in vitro showed HA-CCMs-BP had a similar proteasome activity inhibition as compared to free BTZ at 18 h. The fluorescence imaging using Cy5-labeled HA-CCMs showed that HA-CCMs had a long elimination half-life and enhanced tumor accumulation via HA-mediated uptake mechanism. The therapeutic studies in LP-1 MM-bearing mice revealed better treatment efficacy of HA-CCMs-BP compared with free BTZ, in which HA-CCMs-BP at 3 mg BTZ equiv./kg brought about significant tumor growth inhibition and survival benefits. Loading of lipophilized BTZ into HA-shelled multifunctional micelles has emerged as an exciting approach for bortezomib therapy of MM. STATEMENT OF SIGNIFICANCE: Multiple myeloma (MM) is the second most common hematological malignancy. Bortezomib (BTZ), a potent proteasome inhibitor, provides one of the best treatments for MM. The clinical efficacy of BTZ is, however, limited by its quick clearance, poor selectivity, and significant side effects including myelosuppression and peripheral neuropathy. Here, we report on targeted BTZ therapy of MM in vivo by hyaluronic acid-shelled and core-disulfide-crosslinked biodegradable micelles (HA-CCMs) encapsulating lipophilized BTZ, bortezomib-pinanediol (BP). Our results showed that BP-loaded HA-CCMs exhibit markedly enhanced toleration, broadened therapeutic window, and significantly more effective growth suppression of CD44-overexpressed multiple myeloma in nude mice than free bortezomib. Lipophilized BTZ-loaded HA-CCMs has opened a new avenue for targeted bortezomib therapy of multiple myeloma.

Targeting Membrane Receptors of Ovarian Cancer Cells for Therapy

Ovarian cancer is a leading cause of death worldwide from gynecological malignancies, mainly because there are few early symptoms and the disease is generally diagnosed at an advanced stage. In addition, despite the effectiveness of cytoreductive surgery for ovarian cancer and the high response rates to chemotherapy, survival has improved little over the last 20 years. The management of patients with ovarian cancer also remains similar despite studies showing striking differences and heterogeneity among different subtypes. It is therefore clear that novel targeted therapeutics are urgently needed to improve clinical outcomes for ovarian cancer. To that end, several membrane receptors associated with pivotal cellular processes and often aberrantly overexpressed in ovarian cancer cells have emerged as potential targets for receptor-mediated therapeutic strategies including specific agents and multifunctional delivery systems based on ligand-receptor binding. This review focuses on the profiles and potentials of such strategies proposed for ovarian cancer treatment and imaging.

Overexpression of cysteine-glutamate transporter and CD44 for prediction of recurrence and survival in patients with oral cavity squamous cell carcinoma

BACKGROUND

This study analyzed the expression of CD44 and cystine-glutamate transporter SLC7A11 (xCT) in primary oral cavity squamous cell carcinoma (SCC) and the relationships of expression to tumor recurrence and patient survival.

METHODS

Associations between CD44 and xCT expression and clinicopathologic results were analyzed in 231 patients with oral cavity SCC. Cox proportional hazard analyses were used to identify factors associated with recurrence-free survival (RFS), disease-specific survival (DSS), and overall survival (OS).

RESULTS

Overexpression of CD44 and/or xCT was associated with advanced T classification, perineural invasion, and lymphovascular invasion (P < .05 each). High expression of xCT was also associated with nodal metastasis and depth of invasion (P < .01 each). Multivariate analysis indicated that high expression of xCT and both xCT and CD44 were independent predictors of poor RFS, DSS, and OS (P < .05 each).

CONCLUSION

Overexpression of xCT or xCT plus CD44 may predict posttreatment recurrence and survival in patients with oral cavity SCC.

Overexpression of CD44 Variant 9: A Novel Cancer Stem Cell Marker in Human Cholangiocarcinoma in Relation to Inflammation

Various CD44 isoforms are expressed in several cancer stem cells during tumor progression and metastasis. In particular, CD44 variant 9 (CD44v9) is highly expressed in chronic inflammation-induced cancer. We investigated the expression of CD44v9 and assessed whether CD44v9 is a selective biomarker of human cholangiocarcinoma (CCA). The expression profile of CD44v9 was evaluated in human liver fluke Opisthorchis viverrini-related CCA (OV-CCA) tissues, human CCA (independent of OV infection, non-OV-CCA) tissues, and normal liver tissues. CD44v9 overexpression was detected by immunohistochemistry (IHC) in CCA tissues. There was a higher level of CD44v9 expression and IHC score in OV-CCA tissues than in non-OV-CCA tissues, and there was no CD44v9 staining in the bile duct cells of normal liver tissues. In addition, we observed significantly higher expression of inflammation-related markers, such as S100P and COX-2, in OV-CCA tissues compared to that in non-OV and normal liver tissues. Thus, these findings suggest that CD44v9 may be a novel candidate CCA stem cell marker and may be related to inflammation-associated cancer development.

EI24 Suppresses Tumorigenesis in Pancreatic Cancer via Regulating c-Myc

The EI24 autophagy-associated transmembrane protein is frequently associated with tumor growth and patient survival. In the present study, we found that EI24 was downregulated in pancreatic ductal adenocarcinoma (PDAC) tissues compared with adjacent normal tissues and was associated with cancer cell differentiation. Overexpression of EI24 suppressed cancer cell growth in vitro and in vivo and induced cell cycle S phase arrest, with no impact on caspase-dependent apoptosis. EI24 overexpression also resulted in reduced c-Myc expression, an oncogene in PDAC, accompanied with increased LC3B-II formation, increased Beclin-1, and diminished p62. Together, we propose that EI24 suppresses cell proliferation and prompts cell cycle arrest in pancreatic cancer cells by activating the autophagic lysosomal degradation of c-Myc. Our results suggest a potential mechanism underlying the antitumor effects of EI24 in PDAC and provide insight into the crosstalk between autophagy and cell proliferation involving a possible EI24/Beclin-1/p62/c-Myc signaling pathway.

Characterisation of mesenchymal colon tumour-derived cells in tumourspheres as a model for colorectal cancer progression

Cellular plasticity, the ability of cells to switch from an epitheial phenotype to a mesenchymal one and vice versa, plays a crucial role in tumour progression and metastases development. In 20-25% of patients with colon cancer and in 18% of patients with rectal cancer, metastases are present at the time of the first diagnosis. They are the first cause of colorectal cancer (CRC)-related mortality, defining stage IV CRC, which is characterized by a relatively short overall survival. We previously isolated two primary colon adenocarcinoma cell cultures that had undergone epithelial-mesenchymal transition (EMT), one with a high microsatellite instability phenotype (T88) and one with a chromosomal instability phenotype (T93). The aim of this study was to establish a model with which to study EMT, stemness features and cell plasticity in cancer progression and to examine the effects of incubation with lithium chloride (LiCl), a specific glycogen synthase kinase 3 β (GSK-3β) inhibitor, on these cellular processes. Indeed, GSK3β is an important regulator of cell survival, which promotes tumourigenesis in colon cells by facilitating the crosstalk between colorectal cancer pathways. Thus, we further characterized our system of adherent primary mesenchymal colon cancer cells and their paired tumourspheres by examining the expression and localisation of a panel of markers, including E- and N‑cadherin, CD133, CD44v6, aldehyde dehydrogenase 1 (ALDH1) and leucine-rich repeat‑containing G-protein coupled receptor 5 (LGR5). We also characterised the molecular features of these tumourspheres and examined their response to LiCl. Furthermore, we explored the effects of LiCl on cell motility and plasticity. We demonstrated that LiCl reduced cell migration, stemness features and cell plasticity. We also observed the atypical nuclear localisation of membrane proteins, including N‑cadherin, CD133 and CD44v6 in mesenchymal tumour cells. Of note, CD133 and CD44v6 appeared to localise at the plasma membrane in cells with a more epithelial phenotype, suggesting that the cytoplasmic/nuclear localisation of these proteins could favour and characterize cell plasticity in colorectal cancer progression.

Cell-cell adhesion: linking Wnt/β-catenin signaling with partial EMT and stemness traits in tumorigenesis

Changes in cell adhesion and motility are considered key elements in determining the development of invasive and metastatic tumors. Co-opting the epithelial-to-mesenchymal transition (EMT) process, which is known to occur during embryonic development, and the associated changes in cell adhesion properties in cancer cells are considered major routes for tumor progression. More recent in vivo studies in tumor tissues and circulating tumor cell clusters suggest a stepwise EMT process rather than an “all-or-none” transition during tumor progression. In this commentary, we addressed the molecular mechanisms underlying the changes in cell adhesion and motility and adhesion-mediated signaling and their relationships to the partial EMT states and the acquisition of stemness traits by cancer cells.

Context-dependent functions of KLF4 in cancers: Could alternative splicing isoforms be the key?

Krüppel-like factor 4 (KLF4) is an important transcription factor that is expressed in a variety of tissues and regulates many critical physiologic and cellular processes, including cell proliferation, differentiation, stem cell reprogramming, maintenance of genomic stability, and normal tissue homeostasis. KLF4 has both tumor suppressive and oncogenic functions in gastrointestinal and other cancers. These functions are thought to be context dependent, but how KLF4 exerts these differential functions and the molecular mechanisms behind them remain poorly understood. Recent studies have shown that the KLF4 gene undergoes alternative splicing, and the protein products of certain transcripts antagonize wild-type KLF4 function, suggesting an additional layer of regulation of KLF4 function. Therefore, detailed study of KLF4 alternative splicing may not only provide new insights into the complexity of KLF4 functions but also lead to rational targeting of KLF4 for cancer prevention and therapy.

Cancer Stem Cells, CD44, and Outcomes Following Chemoradiation in Locally Advanced Cervical Cancer: Results From a Prospective Study

PURPOSE

Although cancer stem cells (CSCs) have been reported across solid tumors, there is a dearth of data regarding CSC and its impact on outcomes of cervical cancer.

METHODS AND MATERIALS

From October 2013 to December 2015, patients with squamous cancer of the cervix (stage IB2-IVA) were included. Pretreatment and posttreatment biopsy was obtained and immunohistochemistry was performed for SOX-2, OCT-4, Nanog, CD44, and Podoplanin. All patients received concurrent radiation and brachytherapy to an equivalent dose of 80 to 84 Gy to point A with concurrent weekly cisplatin. Correlation of CSC expression was performed with known prognostic factors. The effect of stem cell expression on disease outcomes was tested within multivariate analysis.

RESULTS

One hundred fifty patients were included. The median dose to point A was 83 Gy (46-89 Gy) and a median of 4 cycles (range, 0-6 cycles) of chemotherapy was administered. At baseline, moderate to strong immunohistochemical expression of SOX-2, OCT-4, Nanog, CD44, and Podoplanin was observed in 12.8%, 4.8%, 24.4%, 15.5%, and 1.3% of patients, respectively. At median follow-up of 30 months (range, 3-51 months), locoregional and distant relapse was observed in 12.2% and 23.1% of patients, of whom 4.7% had both local and distant relapse. The 3-year disease-free survival rate was 87%. On multivariate analysis, moderate to high CSC expression and CD44 low status (hazard ratio [HR] = 8.8; 95% confidence interval [CI], 1.0-77.2; P < .04) independently predicted for locoregional relapse-free survival. International Federation of Gynecology and Obstetrics stage (HR = 2.6; 95% CI, 1.3-5.4; P = .004) and presence of residual tumor after external radiation (HR = 3.5; 95% CI, 1.8-6.5; P = .0001) predicted for a detriment in disease-free survival.

CONCLUSIONS

The presence of stem cell proteins and loss of CD44 independently predicts for reduced locoregional control in locally advanced cervical cancer. Further investigation into the interaction of stem cell and CD44 biology is warranted.

Prognostic value of differentiation status in gastric cancer

Background

Up to date, investigation of the prognostic value of differentiation status mainly focused on signet ring cell and mucinous gastric cancer. Thus, the present study aims to investigate the clinicopathological features and prognosis of gastric cancer patients with well, moderately and poorly differentiation status.

Methods

From September 2008 to March 2015, a total of 3090 gastric cancer patients treated with radical D2 gastrectomy were enrolled in the present study. Clinicopathological characteristics and prognosis of gastric cancer patients with well, moderately and poorly differentiation status were analyzed.

Results

There were 2422 male (78.4%) and 668 female (21.6%). The median age was 58 (20–90) years. There were 370 (12.0%) well differentiated tumors, 836 (27.0%) moderately differentiated tumors and 1884 (61.0%) poorly differentiated tumors. Well and moderately differentiation status were associated with older age, male gender, smaller tumor, shallower invasion, less lymph node involvement and earlier tumor stage (all p < 0.001). Inversely, poorly differentiation status was associated with younger age, female gender, larger tumor, deeper invasion, more lymph node involvement and later tumor stage (all p < 0.001). With respect to prognosis, well differentiation status was associated with favorable overall survival and poorly differentiation status was associated with unfavorable overall survival (p < 0.001). However, after matching with age, tumor size, T and N stage, there was no significant difference among the overall survival of the three groups (p = 0.415).

Conclusions

Well, moderately and poorly differentiation status was significantly associated with clinicopathological features of gastric cancer patients. However, it was not associated with the prognosis of gastric cancer patients.

The osteopontin-CD44 axis in hepatic cancer stem cells regulates IFN signaling and HCV replication

Osteopontin (OPN) is involved in cell proliferation, migration, inflammation, and tumor progression in various tissues. OPN induces stemness by interacting with CD44, but the functional relevance of OPN-mediated interferon (IFN) signaling and hepatitis C virus (HCV) replication in stem cell populations remains unclear. In this study, we investigated the effect of OPN on HCV replication and IFN signaling in cancer stem cells (CSCs) positive for epithelial cell adhesion molecule (EpCAM) and CD44. We show that the EpCAM⁺/CD44⁺ CSCs show marked HCV replication when compared to EpCAM⁻/CD44⁻ cells. In addition, OPN significantly enhances this HCV replication in EpCAM⁺/CD44⁺ CSCs and markedly suppresses IFN-stimulated gene expression. The GSK-3β inhibitor BIO increases the EpCAM⁺/CD44⁺ CSC population and OPN expression and impairs IFN signaling via STAT1 degradation. Taken together, our data suggest that OPN enhances HCV replication in the EpCAM⁺/CD44⁺ CSCs, while it also negatively regulates the IFN signaling pathway via inhibition of STAT1 phosphorylation and degradation. Therefore, OPN may represent a novel therapeutic target for treating HCV-related hepatocellular carcinoma.

Conjugated Bile Acids Promote Invasive Growth of Esophageal Adenocarcinoma Cells and Cancer Stem Cell Expansion via Sphingosine 1-Phosphate Receptor 2-Mediated Yes-Associated Protein Activation

Esophageal adenocarcinoma (EAC) is the sixth leading cause of cancer deaths worldwide and has been dramatically increasing in incidence over the past decade. Gastroesophageal reflux and Barrett esophagus are well-established risk factors for disease progression. Conjugated bile acids (CBAs), including taurocholate (TCA), represent the major bile acids in the gastroesophageal refluxate of advanced Barrett esophagus and EAC patients. Our previous studies suggested that CBA-induced activation of sphingosine 1-phosphate receptor 2 (S1PR2) plays a critical role in promoting cholangiocarcinoma cell invasive growth. However, the role of CBAs in EAC development and underlying mechanisms remains elusive. In the current study, we identified that the expression level of S1PR2 is correlated to invasiveness of EAC cells. TCA significantly promoted cell proliferation, migration, invasion, transformation, and cancer stem cell expansion in highly invasive EAC cells (OE-33 cells), but had less effect on the lower invasive EAC cells (OE-19 cells). Pharmacologic inhibition of S1PR2 with specific antagonist JTE-013 or knockdown of S1PR2 expression significantly reduced TCA-induced invasive growth of OE-33 cells, whereas overexpression of S1PR2 sensitized OE-19 cells to TCA-induced invasive growth. Furthermore, TCA-induced activation of S1PR2 was closely associated with YAP and β-catenin signaling pathways. In conclusion, CBA-induced activation of the S1PR2 signaling pathway is critically involved in invasive growth of EAC cells and represents a novel therapeutic target for EAC.

Overexpression of CD44 Standard Isoform Upregulates HIF-1α Signaling in Hypoxic Breast Cancer Cells

Cluster of differentiation 44 (CD44), a cell surface receptor for hyaluronic acid (HA), is involved in aggressive cancer phenotypes. Herein, we investigated the role of the CD44 standard isoform (CD44s) in hypoxia-inducible factor-1α (HIF-1α) regulation using MCF7 overexpressing CD44s (pCD44s-MCF7). When pCD44s-MCF7 was incubated under hypoxia, levels of HIF-1α, vascular endothelial growth factor, and the HIF-1α response element-derived luciferase activity were significantly increased compared to those in the control MCF7. Incubation of pCD44s-MCF7 cells with HA further increased HIF-1α accumulation, and the silencing of CD44s attenuated HIF-1α elevation, which verifies the role of CD44s in HIF-1α regulation. In addition, the levels of phosphorylated extracellular signal-regulated kinase (ERK) was higher in hypoxic pCD44s-MCF7 cells, and HIF-1α accumulation was diminished by the pharmacological inhibitors of ERK. CD44s-mediated HIF-1α augmentation resulted in two functional outcomes. First, pCD44s-MCF7 cells showed facilitated cell motility under hypoxia via the upregulation of proteins associated with epithelial-mesenchymal transition, such as SNAIL1 and ZEB1. Second, pCD44s-MCF7 cells exhibited higher levels of glycolytic proteins, such as glucose transporter-1, and produced higher levels of lactate under hypoxa. As a consequence of the enhanced glycolytic adaptation to hypoxia, pCD44s-MCF7 cells exhibited a higher rate of cell survival under hypoxia than that of the control MCF7, and glucose deprivation abolished these differential responses of the two cell lines. Taken together, these results suggest that CD44s activates hypoxia-inducible HIF-1α signaling via ERK pathway, and the CD44s-ERK-HIF-1α pathway is involved in facilitated cancer cell viability and motility under hypoxic conditions.

Emerging immunotherapeutic strategies targeting telomerases in genitourinary tumors

Telomerase activity and telomere length are essential for the pathogenesis of several human diseases, including genitourinary tumors. Telomerase constitutes a complex system that includes human telomerase reverse transcriptase (hTERT), human telomerase RNA component (hTR) and telomerase associated protein 1 (TEP1), which are overexpressed in tumor cells compared to normal cells and are involved in the carcinogenesis and progression of renal cell carcinoma (RCC), bladder (BC) and prostate cancer (PCa). In addition, telomerase degraded peptide fragments expressed on the surface of tumor cells lead to their recognition by immune cells. On this scenario, in vitro and in vivo studies have shown effective anti-tumor activity of hTERT-tailored strategies in genitourinary tumors, including active immunotherapy with hTERT-peptide vaccines and passive immunotherapy with hTERT-transduced T cell infusion. This review emphasizes the role of telomerase in the carcinogenesis and progression of genitourinary tumors, thus underlying the potential of emerging telomerase-tailored immunotherapies in these patients.

Inflammatory breast cancer biology: the tumour microenvironment is key

Inflammatory breast cancer (IBC) is a rare and aggressive disease that accounts for ~2-4% of all breast cancers. However, despite its low incidence rate, IBC is responsible for 7-10% of breast cancer-related mortality in Western countries. Thus, the discovery of robust biological targets and the development of more effective therapeutics in IBC are crucial. Despite major international efforts to understand IBC biology, genomic studies have not led to the discovery of distinct biological mechanisms in IBC that can be translated into novel therapeutic strategies. In this Review, we discuss these molecular profiling efforts and highlight other important aspects of IBC biology. We present the intrinsic characteristics of IBC, including stemness, metastatic potential and hormone receptor positivity; the extrinsic features of the IBC tumour microenvironment (TME), including various constituent cell types; and lastly, the communication between these intrinsic and extrinsic components. We summarize the latest perspectives on the key biological features of IBC, with particular emphasis on the TME as an important contributor to the aggressive nature of IBC. On the basis of the current understanding of IBC, we hope to develop the next generation of translational studies, which will lead to much-needed survival improvements in patients with this deadly disease.

The Use of Normal Stem Cells and Cancer Stem Cells for Potential Anti-Cancer Therapeutic Strategy

BACKGROUND

Despite recent advance in conventional cancer therapies including surgery, radiotherapy, chemotherapy, and immunotherapy to reduce tumor size, unfortunately cancer mortality and metastatic cancer incidence remain high. Along with a deeper understanding of stem cell biology, cancer stem cell (CSC) is important in targeted cancer therapy. Herein, we review representative patents using not only normal stem cells as therapeutics themselves or delivery vehicles, but also CSCs as targets for anti-cancer strategy.

METHODS

Relevant patent literatures published between 2005 and 2017 are discussed to present developmental status and experimental results on using normal stem cells and CSCs for cancer therapy and explore potential future directions in this field.

RESULTS

Stem cells have been considered as important element of regenerative therapy by promoting tissue regeneration. Particularly, there is a growing trend to use stem cells as a target drug-delivery system to reduce undesirable side effects in non-target tissues. Noteworthy, studies on CSC-specific markers for distinguishing CSCs from normal stem cells and mature cancer cells have been conducted as a selective anti-cancer therapy with few side effects. Many researchers have also reported the development of various substances with anticancer effects by targeting CSCs from cancer tissues.

CONCLUSION

There has been a continuing increase in the number of studies on therapeutic stem cells and CSC-specific markers for selective diagnosis and therapy of cancer. This review focuses on the current status in the use of normal stem cells and CSCs for targeted cancer therapy. Future direction is also proposed.

Influence of transcriptional variants on metastasis

Cancer metastasis is defined as the dissemination of malignant cells from the primary tumor site, leading to colonization of distant organs and the establishment of a secondary tumor. Metastasis is frequently associated with chemoresistance and is the major cause of cancer-related mortality. Metastatic cells need to acquire the ability to resist to stresses provided by different environments, such as reactive oxygen species, shear stress, hemodynamic forces, stromal composition, and immune responses, to colonize other tissues. Hence, only a small population of cells has a metastasis-initiating potential. Several studies have revealed the misregulation of transcriptional variants during cancer progression, and many splice events can be used to distinguish between normal and tumoral tissue. These variants, which are abnormally expressed in malignant cells, contribute to an adaptive response of tumor cells and the success of the metastatic cascade, promoting an anomalous cell cycle, cellular adhesion, resistance to death, cell survival, migration and invasion. Understanding the different aspects of splicing regulation and the influence of transcriptional variants that control metastatic cells is critical for the development of therapeutic strategies. In this review, we describe how transcriptional variants contribute to metastatic competence and discuss how targeting specific isoforms may be a promising therapeutic strategy.

Downregulation of miR-218-5p promotes invasion of oral squamous cell carcinoma cells via activation of CD44-ROCK signaling

The invasion front of oral squamous cell carcinoma (OSCC) harbors the most aggressive cells of the tumor and is critical for cancer invasion and metastasis. MicroRNAs (miRNAs) play important roles in OSCC progression. In this study, we modelled the OSCC invasion front on a microfluidic chip, and investigated differences in miRNA profiles between cells in the invasion front and those in the tumor mass by small RNA sequencing. We found that miR-218-5p was downregulated in invasion front cells and negatively regulates OSCC invasiveness by targeting the CD44-ROCK pathway. Thus, miR-218-5p may serve as a useful therapeutic target for OSCC. Moreover, invasion front cell isolation based-on microfluidic technology provided a useful strategy for cancer invasion study.

Glycosylation of Cancer Stem Cells: Function in Stemness, Tumorigenesis, and Metastasis

Aberrant glycosylation plays a critical role in tumor aggressiveness, progression, and metastasis. Emerging evidence associates cancer initiation and metastasis to the enrichment of cancer stem cells (CSCs). Several universal markers have been identified for CSCs characterization; however, a specific marker has not yet been identified for different cancer types. Specific glycosylation variation plays a major role in the progression and metastasis of different cancers. Interestingly, many of the CSC markers are glycoproteins and undergo differential glycosylation. Given the importance of CSCs and altered glycosylation in tumorigenesis, the present review will discuss current knowledge of altered glycosylation of CSCs and its application in cancer research.

Mobilized Peripheral Blood versus Cord Blood: Insight into the Distinct Role of Proinflammatory Cytokines on Survival, Clonogenic Ability, and Migration of CD34+ Cells

Inflammation may play a role in cancer. However, the contribution of cytokine-mediated crosstalk between normal hemopoietic stem/progenitor cells (HSPCs) and their (inflammatory) microenvironment is largely elusive. Here we compared survival, phenotype, and function of neonatal (umbilical cord blood (CB)) and adult (normal G-CSF-mobilized peripheral blood (mPB)) CD34⁺ cells after in vitro exposure to combined crucial inflammatory factors such as interleukin- (IL-) 1β, IL-6, tumor necrosis factor- (TNF-) α, or tissue inhibitor of metalloproteinases-1 (TIMP-1). To mimic bone marrow (BM) niche, coculture experiments with normal BM stromal cells (BMSCs) were also performed. We found that combined inflammatory cytokines increased only the in vitro survival of CB-derived CD34⁺ cells by reducing apoptosis. Conversely, selected combinations of inflammatory cytokines (IL-1β + TNF-α, IL-6 + TNF-α, and IL-1β + TNF-α + TIMP-1) mainly enhanced the in vitro CXCR4-driven migration of mPB-derived CD34⁺ cells. TNF-α, alone or in combination, upregulated CD44 and CD13 expression in both sources. Finally, BMSCs alone increased survival/migration of CB- and mPB-derived CD34⁺ cells at the same extent of the combined inflammatory cytokines; importantly, their copresence did not show additive/synergistic effect. Taken together, these data indicate that combined proinflammatory stimuli promote distinct in vitro functional activation of neonatal or adult normal HSPCs.

High CD44 expression mediates p62-associated NFE2L2/NRF2 activation in breast cancer stem cell-like cells: Implications for cancer stem cell resistance

Cluster of differentiation 44 (CD44) is the most common cancer stem cell (CSC) marker and high CD44 expression has been associated with anticancer drug resistance, tumor recurrence, and metastasis. In this study, we aimed to investigate the molecular mechanism by which CD44 and nuclear factor erythroid 2-like 2 (NFE2L2; NRF2), a key regulator of antioxidant genes, are linked to CSC resistance using CD44high breast CSC-like cells. NRF2 expression was higher in CD44high cell populations isolated from doxorubicin-resistant MCF7 (ADR), as well as MCF7, MDA-MB231, and A549 cells, than in corresponding CD44low cells. High NRF2 expression in the CD44highCD24low CSC population (ADR44P) established from ADR cells depended on standard isoform of CD44. Silencing of CD44 or overexpression of CD44 resulted in the reduction or elevation of NRF2, respectively, and treatment with hyaluronic acid, a CD44 ligand, augmented NRF2 activation. As functional implications, NRF2 silencing rendered ADR44P cells to retain higher levels of reactive oxygen species and to be sensitive to anticancer drug toxicity. Moreover, NRF2-silenced ADR44P cells displayed tumor growth retardation and reduced colony/sphere formation and invasion capacity. In line with these, CD44 significantly colocalized with NRF2 in breast tumor clinical samples. The molecular mechanism of CD44-mediated NRF2 activation was found to involve high p62 expression. CD44 elevation led to an increase in p62, and inhibition of p62 resulted in NRF2 suppression in ADR44P. Collectively, our results showed that high CD44 led to p62-associated NRF2 activation in CD44high breast CSC-like cells. NRF2 activation contributed to the aggressive phenotype, tumor growth, and anticancer drug resistance of CD44high CSCs. Therefore, the CD44-NRF2 axis might be a promising therapeutic target for the control of stress resistance and survival of CD44high CSC population within breast tumors.

ALDH1A inhibition sensitizes colon cancer cells to chemotherapy

Background

Recent evidence in cancer research, developed the notion that malignant tumors consist of different subpopulations of cells, one of them, known as cancer stem cells, being attributed many important properties such as enhanced tumorigenicity, proliferation potential and profound multidrug resistance to chemotherapy. Several key stem cells markers were identified in colon cancer. In our study we focused on the aldehyde dehydrogenase type 1 (ALDH1) expression in colon cancer-derived cell lines HT-29/eGFP, HCT-116/eGFP and LS-180/eGFP, and its role in the chemoresistance and tumorigenic potential.

Methods

The effect of pharmacological inhibition of ALDH activity by diethylaminobenzaldehyde (DEAB) and also effect of molecular inhibition by specific siRNA was evaluated in vitro in cultures of human colorectal cell lines. The expression level of different isoenzymes of aldehyde dehydrogenase was determined using qPCR. Changes in cell biology were evaluated by expression analysis, western blot and apoptosis assay. The efficiency of cytotoxic treatment in the presence of different chemotherapeutic drugs was analyzed by fluorimetric assay. Tumorigenicity of cells with specific ALDH1A1 siRNA was tested in xenograft model in vivo.

Results

Treatment by DEAB partially sensitized the tested cell lines to chemotherapeutics. Subsequently the molecular inhibition of specific isoforms of ALDH by ALDH1A1 or ALDH1A3 siRNA led to sensitizing of cell lines HT-29/eGFP, HCT-116/eGFP to capecitabine and 5-FU. On the model of athymic mice we observed the effect of molecular inhibition of ALDH1A1 in HT-29/eGFP cells by siRNA. We observed inhibition of proliferation of subcutaneous xenografts in comparison to control cells.

Conclusion

This research, verifies the significance of the ALDH1A isoforms in multidrug resistance of human colorectal cancer cells and its potential as a cancer stem cell marker. This provides the basis for the development of new approaches regarding the treatment of patients with colorectal adenocarcinoma and potentially the treatment of other tumor malignancies.

Photoacoustic Imaging-Guided Photothermal Therapy with Tumor-Targeting HA-FeOOH@PPy Nanorods

Cancer theragnosis agents with both cancer diagnosis and therapy abilities would be the next generation of cancer treatment. Recently, nanomaterials with strong absorption in near-infrared (NIR) region have been explored as promising cancer theragnosis agents for bio-imaging and photothermal therapy (PTT). Herein, we reported the synthesis and application of a novel multifunctional theranostic nanoagent based on hyaluronan (HA)-coated FeOOH@polypyrrole (FeOOH@PPy) nanorods (HA-FeOOH@PPy NRs) for photoacoustic imaging (PAI)-guided PTT. The nanoparticles were intentionally designed with rod-like shape and conjugated with tumor-targeting ligands to enhance the accumulation and achieve the entire tumor distribution of nanoparticles. The prepared HA-FeOOH@PPy NRs showed excellent biocompatible and physiological stabilities in different media. Importantly, HA-FeOOH@PPy NRs exhibited strong NIR absorbance, remarkable photothermal conversion capability, and conversion stability. Furthermore, HA-FeOOH@PPy NRs could act as strong contrast agents to enhance PAI, conducting accurate locating of cancerous tissue, as well as precise guidance for PTT. The in vitro and in vivo photothermal anticancer activity results of the designed nanoparticles evidenced their promising potential in cancer treatment. The tumor-bearing mice completely recovered after 17 days of PTT treatment without obvious side effects. Thus, our work highlights the great potential of using HA-FeOOH@PPy NRs as a theranostic nanoplatform for cancer imaging-guided therapy.

Cancer Stem Cell Metabolism and Potential Therapeutic Targets

Malignant tumors contain heterogeneous populations of cells in various states of proliferation and differentiation. The presence of cancer stem or initiating cells is a well-established concept wherein quiescent and poorly differentiated cells within a tumor mass contribute to drug resistance, and under permissive conditions, are responsible for tumor recurrence and metastasis. A number of studies have identified molecular markers that are characteristic of tissue-specific cancer stem cells (CSCs). Isolation of CSCs has enabled studies on the metabolic status of CSCs. As metabolic plasticity is a hallmark of cancer cell adaptation, the intricacies of CSC metabolism and their phenotypic behavior are critical areas of research. Unlike normal stem cells, which rely heavily on oxidative phosphorylation (OXPHOS) as their primary source of energy, or cancer cells, which are primarily glycolytic, CSCs demonstrate a unique metabolic flexibility. CSCs can switch between OXPHOS and glycolysis in the presence of oxygen to maintain homeostasis and, thereby, promote tumor growth. Here, we review key factors that impact CSC metabolic phenotype including heterogeneity of CSCs across different histologic tumor types, tissue-specific variations, tumor microenvironment, and CSC niche. Furthermore, we discuss how targeting key players of glycolytic and mitochondrial pathways has shown promising results in cancer eradication and attenuation of disease recurrence in preclinical models. In addition, we highlight studies on other potential therapeutic targets including complex interactions within the microenvironment and cellular communications in the CSC niche to interfere with CSC growth, resistance, and metastasis.

UMI-count modeling and differential expression analysis for single-cell RNA sequencing

Read counting and unique molecular identifier (UMI) counting are the principal gene expression quantification schemes used in single-cell RNA-sequencing (scRNA-seq) analysis. By using multiple scRNA-seq datasets, we reveal distinct distribution differences between these schemes and conclude that the negative binomial model is a good approximation for UMI counts, even in heterogeneous populations. We further propose a novel differential expression analysis algorithm based on a negative binomial model with independent dispersions in each group (NBID). Our results show that this properly controls the FDR and achieves better power for UMI counts when compared to other recently developed packages for scRNA-seq analysis.

Salvianolic acid B reverses multidrug resistance in nude mice bearing human colon cancer stem cells

Salvianolic acid B (SalB) is a water-soluble phenolic compound, extractable from Salvia miltiorrhiza, and has previously been demonstrated to reverse tumor multidrug resistance (MDR) in colon cancer cells. Cancer stem cells (CSCs) are closely associated with drug resistance. Therefore, establishing a nude mouse model bearing human colon CSCs is important for the study of the mechanisms underlying colon cancer drug resistance as well as the reversal of drug resistance. The present study aimed to establish a nude mouse model bearing human colon CSCs and to investigate the effects of SalB on the drug resistance exhibited by the nude mouse model as well as determine its underlying mechanism. Cells from two colon cancer cell lines (LoVo and HCT-116) were cultured in serum-free medium to obtain CSCs-enriched spheroid cells. Following this, nude mice were transplanted with LoVo and HCT-116 colon CSCs to establish the CSC nude mouse model, which was subsequently demonstrated to exhibit MDR. The results of the present study revealed that following treatment with SalB, the chemotherapeutic drug resistance of xenografts was reversed to a certain extent. Western blot analysis was performed to investigate the expression levels of cluster of differentiation (CD)44, CD133, transcription factor sox-2 (SOX2) and ATP-binding cassette sub-family G member 2 (ABCG2) proteins, and the results demonstrated that treatment with SalB downregulated the expression of CD44, SOX2 and ABCG2 proteins in both LoVo and HCT-116 colon CSCs xenografts. In conclusion, the results of the present study revealed that a serum-free suspension method can be performed to successfully isolate colon CSCs. In addition, a nude mice bearing colon CSCs animal model was successfully established, and associated tumors were confirmed to exhibit MDR. Furthermore, SalB was demonstrated to successfully reverse MDR in nude mice bearing LoVo and HCT-116 colon CSCs, as well as suppress the expression of CD44, SOX2 and ABCG2 proteins.

CD44 targeted PLGA nanomedicines for cancer chemotherapy

In recent years scientific community has drawn a great deal of attention towards understanding the enigma of cluster of differentiation-44 (CD44) in order to deliver therapeutic agents more selectively towards tumor tissues. Moreover, its over-expression in variety of solid tumors has attracted drug delivery researchers to target this receptor with nanomedicines. Conventional nanomedicines based on biodegradable polymers such as poly(lactide-co-glycolide) (PLGA) are often associated with insufficient cellular uptake by cancer cells, due to lack of active targeting moiety on their surface. Therefore, to address this limitation, CD44 targeted PLGA nanomedicines has gained considerable interest for enhancing the efficacy of chemotherapeutic agents. In this review, we have elaborately discussed the recent progress in the design and synthesis of CD44 targeted PLGA nanomedicines used to improve tumor-targeted drug delivery. We have also discussed strategies based on co-targeting of CD44 with other targeting moieties such as folic acid, human epidermal growth factor 2 (HER2), monoclonal antibodies using PLGA based nanomedicines.

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.

The biology and role of CD44 in cancer progression: therapeutic implications

CD44, a non-kinase transmembrane glycoprotein, is overexpressed in several cell types including cancer stem cells and frequently shows alternative spliced variants that are thought to play a role in cancer development and progression. Hyaluronan, the main ligand for CD44, binds to and activates CD44 resulting in activation of cell signaling pathways that induces cell proliferation, increases cell survival, modulates cytoskeletal changes, and enhances cellular motility. The different functional roles of CD44 standard (CD44s) and specific CD44 variant (CD44v) isoforms are not fully understood. CD44v contain additional peptide motifs that can interact with and sequester growth factors and cytokines at the cell surface thereby functioning as coreceptors to facilitate cell signaling. Moreover, CD44v were expressed in metastasized tumors, whereas switching between CD44v and CD44s may play a role in regulating epithelial to mesenchymal transition (EMT) and in the adaptive plasticity of cancer cells. Here, we review current data on the structural and functional properties of CD44, the known roles for CD44 in tumorigencity, the regulation of CD44 expression, and the potential for targeting CD44 for cancer therapy.

Paragangliomas arise through an autonomous vasculo-angio-neurogenic program inhibited by imatinib

Tumours can be viewed as aberrant tissues or organs sustained by tumorigenic stem-like cells that engage into dysregulated histo/organogenetic processes. Paragangliomas, prototypical organoid tumours constituted by dysmorphic variants of the vascular and neural tissues found in normal paraganglia, provide a model to test this hypothesis. To understand the origin of paragangliomas, we built a biobank comprising 77 cases, 18 primary cultures, 4 derived cell lines, 80 patient-derived xenografts and 11 cell-derived xenografts. We comparatively investigated these unique complementary materials using morphofunctional, ultrastructural and flow cytometric assays accompanied by microRNA studies. We found that paragangliomas contain stem-like cells with hybrid mesenchymal/vasculoneural phenotype, stabilized and expanded in the derived cultures. The viability and growth of such cultures depended on the downregulation of the miR-200 and miR-34 families, which allowed high PDGFRA and ZEB1 protein expression levels. Both tumour tissue- and cell culture-derived xenografts recapitulated the vasculoneural paraganglioma structure and arose from mesenchymal-like cells through a fixed developmental sequence. First, vasculoangiogenesis organized the microenvironment, building a perivascular niche which in turn supported neurogenesis. Neuroepithelial differentiation was associated with severe mitochondrial dysfunction, not present in cultured paraganglioma cells, but acquired in vivo during xenograft formation. Vasculogenesis was the Achilles’ heel of xenograft development. In fact, imatinib, that targets endothelial-mural signalling, blocked paraganglioma xenograft formation (11 xenografts from 12 cell transplants in the control group versus 2 out of 10 in the treated group, P = 0.0015). Overall our key results were unaffected by the SDHx gene carrier status of the patient, characterized for 70 out of 77 cases. In conclusion, we explain the biphasic vasculoneural structure of paragangliomas and identify an early and pharmacologically actionable phase of paraganglioma organization.

PanCD44 Immunohistochemical Evaluation in Prostatectomies from Patients with Adenocarcinoma

Introduction

CD44 has been proposed as a prognostic marker and a stem cell marker but studies in patients with prostate cancer have yielded inconsistent results.

Patients and Methods

Patients submitted to radical prostatectomy between 2008 and 2013 at a university hospital were followed with biannual serum PSA tests to determine the biochemical recurrence (BR). Archived paraffin blocks with neoplastic and nonneoplastic tissue were evaluated immunohistochemically for a panCD44 and MYC.

Results

Sixty-nine patients completed follow-up and were included. CD44 positivity was observed in inflammatory cells (42%), nonneoplastic epithelium (39.7%), and neoplastic tissue (12.3%). In nonneoplastic tissues staining was observed in basal and luminal cells with the morphology of terminally differentiated cells. In neoplastic tissues, CD44 negativity was correlated with higher Gleason scores (Rho = −0.204; p = 0.042) and higher preoperative serum PSA levels when evaluated continuously (p = 0.029). CD44 expression was not associated with tumor stage (p = 0.668), surgical margin status (p = 0.471), or BR (p = 0.346), nor was there any association between CD44 and MYC expression in neoplastic tissue (p = 1.0).

Conclusion

In the bulk of cells, the minority of cancer stem cells would not be detected by immunohistochemistry using panCD44. As a prognostic marker, its expression was weakly correlated with Gleason score and preoperative PSA level, but not with surgical margin status, tumor stage, or BR.

CD44 overexpression related to lymph node metastasis and poor prognosis of pancreatic cancer

BACKGROUND

CD44 has recently been reported as a biomarker for pancreatic cancer. However, the predictive value of CD44 in pancreatic cancer remains controversial. Therefore, we performed this meta-analysis to evaluate the association between the expression of CD44 and clinicopathological features, and the outcome of pancreatic cancer patients.

MATERIALS AND METHOD

A comprehensive literature search was performed using PubMed, Embase, and Chinese National Knowledge Infrastructure. The statistical analysis was conducted using Stata software.

RESULTS

A total of nine studies including 583 cases were included in this meta-analysis. The meta-analysis indicated that CD44 overexpression was associated with poor five-year overall survival rate (OR 0.52; 95% CI 0.30, 0.91; P = 0.02), more lymph node invasion (OR 3.14 (positive vs. negative); 95% CI 1.47, 6.73; P = 0.003), more advanced T stage (OR 2.4 (T3,4 vs. T1,2); 95% CI 1.28, 4.52; P = 0.007), and more advanced TNM stage (OR 4.53 (III~IV vs. I~II); 95% CI 1.46, 14.08; P = 0.01). However, CD44 overexpression was not associated with other clinicopathological features, such as tumor size, differentiation, and distance metastasis.

CONCLUSIONS

The current evidence suggests that CD44 is an efficient prognostic factor in pancreatic cancer.

Stemness-Attenuating miR-503-3p as a Paracrine Factor to Regulate Growth of Cancer Stem Cells

Cancer stem cells (CSCs) with self-renewal abilities endorse cellular heterogeneity, resulting in metastasis and recurrence. However, there are no promising therapeutics directed against CSCs. Herein, we found that miR-503-3p inhibited tumor growth via the regulation of CSC proliferation and self-renewal. miR-503-3p, isolated from human adipose stem cell- (ASC-) derived exosomes, suppressed initiation and progression of CSCs as determined by anchorage-dependent (colony formation) and anchorage-independent (tumorsphere formation) assays. The expression of pluripotency genes was significantly decreased in miR-503-3p-treated CSCs. Furthermore, xenografts, which received miR-503-3p, exhibited remarkably reduced tumor growth in vivo. Thus, miR-503-3p may function as a stemness-attenuating factor via cell-to-cell communications.

Metastatic ability and the epithelial-mesenchymal transition in induced cancer stem-like hepatoma cells

Cancer stem cells (CSCs) are thought to play important roles in cancer malignancy. Previously, we successfully induced sphere cancer stem-like cells (CSLCs) from several cell lines and observed the property of chemoresistance. In the present study, we examined the metastatic potential of these induced CSLCs. Sphere cancer stem-like cells were induced from a human hepatoma cell line (SK-HEP-1) in a unique medium containing neural survival factor-1. Splenic injection of cells into immune-deficient mice was used to assess hematogenous liver metastasis. Transcriptomic strand-specific RNA-sequencing analysis, quantitative real-time PCR, and flow cytometry were carried out to examine the expression of epithelial-mesenchymal transition (EMT)-related genes. Splenic injection of CSLCs resulted in a significantly increased frequency of liver metastasis compared to parental cancer cells (P < .05). In CSLCs, a mesenchymal marker, Vimentin, and EMT-promoting transcription factors, Snail and Twist1, were upregulated compared to parental cells. Correspondingly, significant enrichment of the molecular signature of the EMT in CSLCs relative to parental cancer cells was shown (q < 0.01) by RNA-sequencing analysis. This analysis also revealed differential expression of CD44 isoforms between CSLCs and parental cancer cells. Increasing CD44 isoforms containing an extra exon were observed, and the standard CD44 isoform decreased in CSLCs compared to parental cells. Interestingly, another CD44 variant isoform encoding a short cytoplasmic tail was also upregulated in CSLCs (11.7-fold). Our induced CSLCs possess an increased liver metastatic potential in which promotion of the EMT and upregulation of CD44 variant isoforms, especially short-tail, were observed.

Expression and shedding of CD44 in the endometrium of women with endometriosis and modulating effects of vitamin D: A randomized exploratory trial

Endometriosis is an estrogen-dependent disease. The impaired estrogen and progesterone signaling over-activates the Wnt/β-catenin pathway in endometriosis patients, which can explain the increased invasion potency of endometrial cells derived from the endometrium of women with endometriosis. The regulatory effects of vitamin D on Wnt/β-catenin pathway were demonstrated by previous studies. According to gene prioritization method, among Wnt target genes, CD44 was in high ranking in relation to endometriosis. The aim of this study is to investigate the expression of CD44 in the endometrium of women with endometriosis and to study the effects of vitamin D on its expression. This prospective study was performed, during a 12 months period from December 2015 to November 2016, on healthy women as the control group (n = 14) and endometriosis patients (n = 34). The endometriosis patients randomly divided into two groups: One group treated according to the routine protocol and the other group, alongside the routine protocol, took 50,000 IU vitamin D weekly for 12-14 weeks. Blood, endometrial fluid, and endometrial tissue samples were obtained from the control group and endometriosis groups before and after the intervention. We used in silico gene prioritization to study the relevance of CD44. The expression of CD44 was evaluated using the techniques of Western blot, real-time polymerase chain reaction, and ELISA. The eutopic endometrium of women with endometriosis in mid-secretory phase expressed significantly higher levels of CD44s, CD44V, and CD44v6. The concentration of soluble CD44 in the serum and endometrial fluid of endometriosis patients was higher than of healthy women. The expression level of CD44s, CD44V, and CD44v6 in the eutopic endometrium as well as the concentration of soluble CD44 in the endometrial fluid was decreased after modification of the circulating levels of 25(OH)D. It seems that the increased expression and extensive shedding of CD44 in eutopic endometrium play a role in the pathogenesis of endometriosis. Vitamin D can control and modify this process at least in part. We suggest more in vivo investigations on the therapeutic potency of vitamin D in endometriosis.

Quantitative assessment of CD44 genetic variants and cancer susceptibility in Asians: a meta-analysis

CD44 is a well-established cancer stem cell marker playing a crucial role in tumor metastasis, recurrence and chemo-resistance. Genetic variants of CD44 have been shown to be associated with susceptibility to various cancers; however, the results are confounding. Hence, we performed a meta-analysis to clarify these associations more accurately. Overall, rs13347 (T vs. C: OR=1.30, p=<0.004, p_corr=0.032; CT vs. CC: OR=1.29, p=0.015, p_corr=0.047; TT vs. CC: OR=1.77, p=<0.000, p_corr=0.018; CT+TT vs. CC: OR=1.34, p=<0.009, p_corr=0.041) and rs187115 (GG vs. AA: OR=2.34, p=<0.000, p_corr=0.025; AG vs. AA: OR=1.59, p=<0.000, p_corr=0.038; G vs. A allele OR=1.56, p=0.000, p_corr=0.05; AG+GG vs. AA: OR=1.63, p=<0.000, p_corr=0.013) polymorphisms were found to significantly increase the cancer risk in Asians. On the other hand, rs11821102 was found to confer low risk (A vs. G: OR=0.87, p=<0.027, p_corr=0.04; AG vs. GG: OR=0.85, p=<0.017, p_corr=0.01; AG+AA vs. GG: OR=0.86, p=<0.020, p_corr=0.02). Based on our analysis, we suggest significant role of CD44 variants (rs13347, rs187115 and rs11821102) in modulating individual's cancer susceptibility in Asians. Therefore, these variants may be used as predictive genetic biomarkers for cancer predisposition in Asian populations. However, more comprehensive studies involving other cancers and/or populations, haplotypes, gene-gene and gene-environment interactions are necessary to delineate the role of these variants in conferring cancer risk.

Galunisertib suppresses the staminal phenotype in hepatocellular carcinoma by modulating CD44 expression

Cancer stem cells (CSCs) niche in the tumor microenvironment is responsible for cancer recurrence and therapy failure. To better understand its molecular and biological involvement in hepatocellular carcinoma (HCC) progression, one can design more effective therapies and tailored then to individual patients. While sorafenib is currently the only approved drug for first-line treatment of advanced stage HCC, its role in modulating the CSC niche is estimated to be small. By contrast, transforming growth factor (TGF)-β pathway seems to influence the CSC and thus may impact hallmarks of HCC, such as liver fibrosis, cirrhosis, and tumor progression. Therefore, blocking this pathway may offer an appealing and druggable target. In our study, we have used galunisertib (LY2157299), a selective ATP-mimetic inhibitor of TGF-β receptor I (TGFβI/ALK5) activation, currently under clinical investigation in HCC patients. Because the drug resistance is mainly mediated by CSCs, we tested the effects of galunisertib on stemness phenotype in HCC cells to determine whether TGF-β signaling modulates CSC niche and drug resistance. Galunisertib modulated the expression of stemness-related genes only in the invasive (HLE and HLF) HCC cells inducing a decreased expression of CD44 and THY1. Furthermore, galunisertib also reduced the stemness-related functions of invasive HCC cells decreasing the formation of colonies, liver spheroids and invasive growth ability. Interestingly, CD44 loss of function mimicked the galunisertib effects on HCC stemness-related functions. Galunisertib treatment also reduced the expression of stemness-related genes in ex vivo human HCC specimens. Our observations are the first evidence that galunisertib effectiveness overcomes stemness-derived aggressiveness via decreased expression CD44 and THY1.

Oral cancer stem cells - properties and consequences

Research on cancer stem cells (CSCs) has greatly increased in the field of medicine and pathology; however, some conceptual misunderstandings are still present among the public as well as within the general scientific community that is not yet familiar with the subject. The very first problem is the misinterpretation of CSCs as a synonym of their normal counterparts, the well-known stem cells (SCs). Particularly in Dentistry, another common mistake is the misinterpretation of oral CSCs as normal tooth-derived SCs. The present review aims to clarify important concepts related to normal SCs and CSCs, as well as discuss the relevance of CSCs to the development, metastasis and therapy resistance of oral squamous cell carcinoma.