ALDH1A1 promotes immune escape of tumor cells through ZBTB7B-glycolysis pathway.

The primary impediment to the success of immunotherapy lies in the immune evasion orchestrated by tumors, contributing to the suboptimal overall response rates observed. Despite this recognition, the intricacies of the underlying mechanisms remain incompletely understood. Through preliminary detection of clinical patient tissues, we have found that ALDH1A1 was a key gene for the prognosis of cancer patients and tumor glycolysis. In vitro experiments and tumor formation in nude mice suggested that targeting ALDH1A1 could inhibit tumor growth. Through further analysis of xenograft tumor models in immune-normal mice and flow cytometry, we found that deficiency in ALDH1A1 could promote immune system suppression of tumors in vivo. Specifically, RNA-seq analysis, combined with qPCR and western blot, identified the transcription factor ZBTB7B as downstream of ALDH1A1. The binding sites of the transcription factor ZBTB7B on the LDHA promoter region, which is responsible for regulating the rate-limiting enzyme gene LDHA in glycolysis, were determined using luciferase reporter gene detection and Chip-qPCR, respectively. In addition, the increased SUMOylation of ZBTB7B stabilized its transcriptional activity. Further in vivo and in vitro experiments confirmed that the combination of targeting ALDH1A1 and ZBTB7B with immune checkpoint inhibitors could synergistically inhibit tumors in vivo. Finally, after conducting additional verification of patient tissue and clinical data, we have confirmed the potential translational value of targeting ALDH1A1 and ZBTB7B for tumor immunotherapy. These results emphasize the potential translational significance of targeting ALDH1A1 and ZBTB7B in the realm of tumor immunotherapy. The convergence of ALDH1A1 inhibition and immune checkpoint blockade, particularly with PD-L1/PD-1 mAb, presents a compelling avenue for curtailing tumor immune escape.

Dynamic upregulation of retinoic acid signal in the early postnatal murine heart promotes cardiomyocyte cell cycle exit and maturation.

The adult mammalian heart has extremely limited cardiac regenerative capacity. Most cardiomyocytes live in a state of permanent cell-cycle arrest and are unable to re-enter the cycle. Cardiomyocytes switch from cell proliferation to a maturation state during neonatal development. Although several signaling pathways are involved in this transition, the molecular mechanisms by which these inputs coordinately regulate cardiomyocyte maturation are not fully understood. Retinoic acid (RA) plays a pivotal role in development, morphogenesis, and regeneration. Despite the importance of RA signaling in embryo heart development, little is known about its function in the early postnatal period. We found that mRNA expression of aldehyde dehydrogenase 1 family member A2 (Aldh1a2), which encodes the key enzyme for synthesizing all-trans retinoic acid (ATRA) and is an important regulator for RA signaling, was transiently upregulated in neonatal mouse ventricles. Single-cell transcriptome analysis and immunohistochemistry revealed that Aldh1a2 expression was enriched in cardiac fibroblasts during the early postnatal period. Administration of ATRA inhibited cardiomyocyte proliferation in cultured neonatal rat cardiomyocytes and human cardiomyocytes. RNA-seq analysis indicated that cell proliferation-related genes were downregulated in prenatal rat ventricular cardiomyocytes treated with ATRA, while cardiomyocyte maturation-related genes were upregulated. These findings suggest that RA signaling derived from cardiac fibroblasts is one of the key regulators of cardiomyocyte proliferation and maturation during neonatal heart development.

The role of ALDH1A1 in glioblastoma proliferation and invasion.

High-grade gliomas, including glioblastoma multiforme (GBM), continue to be a leading aggressive brain tumor in adults, marked by its rapid growth and invasive nature. Aldehyde dehydrogenase 1 family, member A1 (ALDH1A1), an enzyme, plays a significant role in tumor progression, yet its function in high-grade gliomas is still poorly investigated. In this study, we evaluated ALDH1A1 levels in clinical samples of GBM. We also assessed the prognostic significance of ALDH1A1 expression in GBM and LGG (low grade glioma) patients using TCGA (The Cancer Genome Atlas) database analysis. The MTT and transwell assays were utilized to examine cell growth and the invasive capability of U87 cells, respectively. We quantitatively examined markers for cell proliferation (Ki-67 and cyclin D1) and invasion (MMP2 and 9). A Western blot test was conducted to determine the downstream signaling of ALDH1A1. We found a notable increase in ALDH1A1 expression in high-grade gliomas compared to their low-grade counterparts. U87 cells that overexpressed ALDH1A1 showed increased cell growth and invasion. We found that ALDH1A1 promotes the phosphorylation of AKT, and inhibiting AKT phosphorylation mitigates the ALDH1A1's effects on tumor growth and migration. In summary, our findings suggest ALDH1A1 as a potential therapeutic target for GBM treatment.

ALDH1A1 as a marker for metastasis initiating cells: A mechanistic insight.

Since metastasis accounts for the majority of cancer morbidity and mortality, attempts are focused to block metastasis and metastasis initiating cellular programs. It is generally believed that hypoxia, reactive oxygen species (ROS) and the dysregulated redox pathways regulate metastasis. Although induction of epithelial to mesenchymal transition (EMT) can initiate cell motility to different sites other than the primary site, the initiation of a secondary tumor at a distant site depends on self-renewal property of cancer stem cell (CSC) property. That subset of metastatic cells possessing CSC property are referred to as metastasis initiating cells (MICs). Among the different cellular intermediates regulating metastasis in response to hypoxia by inducing EMT and self-renewal property, ALDH1A1 is a critical molecule, which can be used as a marker for MICs in a wide variety of malignancies. The cytosolic ALDHs can irreversibly convert retinal to retinoic acid (RA), which initiates RA signaling, important for self-renewal and EMT. The metastasis permissive tumor microenvironment increases the expression of ALDH1A1, primarily through HIF1α, and leads to metabolic reprograming through OXPHOS regulation. The ALDH1A1 expression and its high activity can reprogram the cancer cells with the transcriptional upregulation of several genes, involved in EMT through RA signaling to manifest hybrid EMT or Hybrid E/M phenotype, which is important for acquiring the characteristics of MICs. Thus, the review on this topic highlights the use of ALDH1A1 as a marker for MICs, and reporters for the marker can be effectively used to trace the population in mouse models, and to screen drugs that target MICs.

Establishing nomograms for predicting disease-free survival and overall survival in patients with breast cancer.

BACKGROUND: Prognostic factors-based nomograms have been utilised to detect the likelihood of the specific cancer events. We have focused on the roles of aldehyde dehydrogenase 1 (ALDH1) and p-AKT in predicting the prognosis of BC patients. This study was designed to establish nomograms based on the integration of aldehyde dehydrogenase 1 (ALDH1) and p-AKT in predicting the disease-free survival (DFS) and overall survival (OS) of breast cancer (BC) patients. METHODS: Demographic and clinical data were obtained from BC patients admitted to our hospital between September 2015 and August 2016. Univariate and multivariate Cox regression analyses were utilised to analyse the risk factors of recurrence and mortality. The nomograms for predicting the DFS and OS were established using the screened risk factors. Stratified analysis was performed with the cut-off value of exp (pi) of 4.0-fold in DFS and OS, respectively. RESULTS: Multivariate Cox regression analysis indicated that ALDH, p-AKT and pathological stage III were independent risk factors for the recurrence among BC patients. ALDH1, p-AKT, pathological stage III and ER-/PR-/HER2- were independent risk factors for the mortality among BC patients. The established nomograms based on these factors were effective for predicting the DFS and OS with good agreement to the calibration curve and acceptable area under the receiver operating characteristic (ROC) curve. Finally, stratified analyses showed patients with a low pi showed significant decrease in the DFS and OS compared with those of high risk. CONCLUSION: We established nomograms for predicting the DFS and OS of BC patients based on ALDH1, p-AKT and pathological stages. The ER-/PR-/HER2- may be utilised to predict the OS rather than DFS in the BC patients.

Many breast cancer patients show poor response after treatment due to recurrence and metastasis. Therefore, early prediction of the disease-free survival and overall survival is crucial to the treatment outcome and clinical decision-making. In this study, we established nomograms with the demographic and clinical data from breast cancer patients admitted to our hospital between September 2015 and August 2016. Univariate and multivariate Cox regression analyses showed that some important proteins and signalling pathways were risk factors for decreased disease-free survival and overall survival of breast cancer patients. On this basis, we established an effective nomogram for predicting the disease-free survival and overall survival of these patients based on these factors. This study offers new options in the predicting the treatment outcome of breast cancer patients.

ALDH1+ tumor stem cells promote the progression of malignant fibrous tissue sarcoma by inhibiting SYNPO2 through hsa-mir-206.

This research aims to explore the mechanism by which microRNAs may regulate the biological behavior of tumor cells in ALDH1+ fibrosarcoma. We identified differentially expressed miRNAs in ALDH + NMFH-1 cells, screened genes related to sarcoma metastasis in the TCGA database, and finally obtained key genes regulated by miRNAs that are involved in metastasis. The function and mechanism of these key genes were then validated at the cellular level. Using the ULCAN database, a significant correlation was found between hsa-mir-206 and mortality in sarcoma patients. WGCNA analysis identified 352 genes related to tumor metastasis. Through Venn diagrams, we obtained 15 metastasis-related genes regulated by hsa-mir-206. Survival analysis showed that SYNPO2 expression is significantly correlated with survival rate and is significantly underexpressed in multiple tumors. SYNPO2 showed a negative correlation with macrophages and a positive correlation with CD8+ T cells. After inhibiting the expression of hsa-mir-206 with siRNA plasmids, the mRNA expression of SYNPO2 was significantly upregulated. The results of CCK8 assay, scratch assay, and transwell assay showed that the proliferation and migration ability of NFMH-1 cells were promoted after SYNPO2 was inhibited. ALDH1+ tumor stem cells promote the proliferation and invasion of malignant fibrous histiocytoma cells by inhibiting SYNPO2 through hsa-mir-206.

Dual-responsive near-infrared turn-on fluorescent probe for cancer stem cell-specific visualization.

Aldehyde dehydrogenase 1A1 (ALDH1A1) stands out as one of the most reliable intracellular biomarkers for stem cells because it is expressed in both cancer stem cells (CSCs) and normal somatic stem cells (NSCs). Although several turn-on fluorescent probes for ALDH1A1 have been developed to visualize CSCs in cancer cells, the discrimination of CSCs from NSCs is difficult. We here report an AND-type dual-responsive fluorescent probe, CHO_ßgal, the near-infrared fluorescence of which can be turned on after responding to both ALDH1A1 and ß-galactosidase. The AND-type dual responsiveness enables CSCs to be clearly visualized, whereas NSCs are non-emissive in microscopy. CSC-positive metastasis model lungs were successfully discriminated from normal lungs in ex vivo staining experiments using CHO_ßgal, whereas the single-input ALDH1A1-responsive probe failed to achieve this discrimination owing to pronounced false-positive fluorescence output from lung NSCs. In tissue slice staining experiments, even in the presence of adjacent normal tissues, the peripheral region-specific localization of CSCs was clear. The versatility of CHO_ßgal holds promise not only as a fundamental in vitro research tool for visualizing CSCs but also as a valuable asset in practical tissue staining diagnosis, significantly contributing to the assessment of cancer malignancy.

RUNX3 exerts tumor-suppressive role through inhibiting EXOSC4 expression.

Breast cancer severely affects women health. 70% of breast cancer are estrogen receptor positive. Breast cancer stem cells are a group of tumor with plasticity, causing tumor relapse and metastasis. RUNX3 is a tumor suppressor frequently inactivated in estrogen receptor positive breast cancer. However, the mechanism of how RUNX3 is involved in the regualation of cancer stem cell traits in estrogen receptor positive breast cancer remains elusive. In this study, we utilized cut-tag assay to investigate the binding profile RUNX3 in BT474 and T47D cell, and confirmed EXOSC4 as the bona-fide target of RUNX3; RUNX3 could bind to the promoter are of EXOSC4 to suppress its expression. Furthermore, EXOSC4 could increase the colony formation, cell invasion and mammosphere formation ability of breast cancer cells and upregulate the the expression of SOX2 and ALDH1. Consistent with these findings, EXOSC4 was associated with poorer survival for Luminal B/Her2 breast cancer patiens. At last, we confirmed that EXOSC4 mediated the tumor suppressive role of RUNX3 in breast cancer cells. In conclusion, we demonstrate that RUNX3 directly binds to the promoter region of EXOSC4, leading to the suppression of EXOSC4 expression and exerting a tumor-suppressive effect in estrogen receptor postivive breast cancer cells.

Associations of stem cell markers CD44, CD24 and ALDH1A1 with mammographic breast density in women with benign breast biopsies.

BACKGROUND: We examined associations of CD44, CD24 and ALDH1A1 breast stem cell markers with mammographic breast density (MBD), a well-established breast cancer (BCa) risk factor. METHODS: We included 218 cancer-free women with biopsy-confirmed benign breast disease within the Nurses' Health Study (NHS) and NHSII. The data on BCa risk factors were obtained from biennial questionnaires. Immunohistochemistry (IHC) was done on tissue microarrays. For each core, the IHC expression was assessed using a semi-automated platform and expressed as percent of positively stained cells for each marker out of the total cell count. MBD was assessed with computer-assisted techniques. Generalised linear regression was used to examine the associations of each marker with square root-transformed percent density (PD), absolute dense and non-dense areas (NDA), adjusted for BCa risk factors. RESULTS: Stromal CD44 and ALDH1A1 expression was positively associated with PD (≥ 10% vs. <10% ß = 0.56, 95% confidence interval [CI] [0.06; 1.07] and ß = 0.81 [0.27; 1.34], respectively) and inversely associated with NDA (ß per 10% increase = -0.17 [-0.34; -0.01] and ß for ≥10% vs. <10% = -1.17 [-2.07; -0.28], respectively). Epithelial CD24 expression was inversely associated with PD (ß per 10% increase = -0.14 [-0.28; -0.01]. Stromal and epithelial CD24 expression was positively associated with NDA (ß per 10% increase = 0.35 [0.2 × 10-2; 0.70] and ß per 10% increase = 0.34 [0.11; 0.57], respectively). CONCLUSION: Expression of stem cell markers is associated with MBD.

Modeling alcohol-associated liver disease in humans using adipose stromal or stem cell-derived organoids.

Alcohol-associated liver disease (ALD) is a prevalent liver disease, yet research is hampered by the lack of suitable and reliable human ALD models. Herein, we generated human adipose stromal/stem cell (hASC)-derived hepatocellular organoids (hAHOs) and hASC-derived liver organoids (hALOs) in a three-dimensional system using hASC-derived hepatocyte-like cells and endodermal progenitor cells, respectively. The hAHOs were composed of major hepatocytes and cholangiocytes. The hALOs contained hepatocytes and nonparenchymal cells and possessed a more mature liver function than hAHOs. Upon ethanol treatment, both steatosis and inflammation were present in hAHOs and hALOs. The incubation of hALOs with ethanol resulted in increases in the levels of oxidative stress, the endoplasmic reticulum protein thioredoxin domain-containing protein 5 (TXNDC5), the alcohol-metabolizing enzymes ADH1B and ALDH1B1, and extracellular matrix accumulation, similar to those of liver tissues from patients with ALD. These results present a useful approach for understanding the pathogenesis of ALD in humans, thus facilitating the discovery of effective treatments.

CSChighE-cadherinlow immunohistochemistry panel predicts poor prognosis in oral squamous cell carcinoma.

Identifying marker combinations for robust prognostic validation in primary tumour compartments remains challenging. We aimed to assess the prognostic significance of CSC markers (ALDH1, CD44, p75NTR, BMI-1) and E-cadherin biomarkers in OSCC. We analysed 94 primary OSCC and 67 metastatic lymph node samples, including central and invasive tumour fronts (ITF), along with clinicopathological data. We observed an increase in ALDH1+/CD44+/BMI-1- tumour cells in metastatic lesions compared to primary tumours. Multivariate analysis highlighted that elevated p75NTR levels (at ITF) and reduced E-cadherin expression (at the tumour centre) independently predicted metastasis, whilst ALDH1high exhibited independent predictive lower survival at the ITF, surpassing the efficacy of traditional tumour staging. Then, specifically at the ITF, profiles characterized by CSChighE-cadherinlow (ALDH1highp75NTRhighE-cadherinlow) and CSCintermediateE-cadherinlow (ALDH1 or p75NTRhighE-cadherinlow) were significantly associated with worsened overall survival and increased likelihood of metastasis in OSCC patients. In summary, our study revealed diverse tumour cell profiles in OSCC tissues, with varying CSC and E-cadherin marker patterns across primary tumours and metastatic sites. Given the pivotal role of reduced survival rates as an indicator of unfavourable prognosis, the immunohistochemistry profile identified as CSChighE-cadherinlow at the ITF of primary tumours, emerges as a preferred prognostic marker closely linked to adverse outcomes in OSCC.

Molecular characterization and expression profile of the ALDH1A1 gene and its functions in yak luteal cells.

The ALDH1A1 gene encodes a cytoplasmic member of the aldehyde dehydrogenase 1 family, which plays an important role in regulating animal reproductive performance, including estrus cycle and embryonic development. The aim of this study was to characterize ALDH1A1 activity in ovaries of 3-5 year-old yaks and to determine its effects on cell proliferation, apoptosis, and progesterone secretion in luteal cells (LCs). The coding sequence (CDS) of the ALDH1A1 gene was cloned by reverse transcription-PCR and immunohistochemical analysis was used to confirm localization of the ALDH1A1 protein in the ovary. To assess the activity of ALDH1A1 in regulating progesterone secretion, si-ALDH1A1 was transfected into LCs in vitro and progesterone levels in LC supernatants were measured by ELISA. The interference efficiency was assessed by real-time quantitative PCR (RT-qPCR) and immunofluorescence staining, and cell proliferation and apoptosis were evaluated by EdU and TUNEL staining, respectively. The cloned ALDH1A1 sequence contained 1462 bp, encoding 487 amino acids. Immunohistochemical analysis showed that ALDH1A1 protein expression, which was significantly higher in LCs, was mainly found in antral follicles and the corpus luteum (CL). The expression of ALDH1A1 mRNA in LCs was effectively inhibited by si-ALDH1A1transfection, and progesterone secretion was markedly decreased along with the significant down-regulation of progesterone pathway-related genes, STAR, CYP11A1, CYP19A1, CYP17A1, 3ß-HSD, and HSD17B1. Knockdown of ALDH1A1 mRNA expression decreased cell proliferation and increased apoptosis in LCs. The mRNA expression of the proliferation-related genes, PCNA, CCND1, CCNB1 and CDC25A, was significantly down-regulated, while expression of the apoptosis-promoting CASP3 gene was significantly increased. In summary, we characterized the yak ALDH1A1 gene and revealed that ALDH1A1 knockdown promoted apoptosis, repressed cell proliferation, and decreased progesterone secretion by yak LCs, potentially by regulating the mRNA expression of genes related to proliferation, apoptosis, and progesterone synthesis and secretion.

Impact of the thyroid hormone T3 and its nuclear receptor TRα1 on colon cancer stem cell phenotypes and response to chemotherapies.

Colorectal cancers (CRCs) are highly heterogeneous and show a hierarchical organization, with cancer stem cells (CSCs) responsible for tumor development, maintenance, and drug resistance. Our previous studies showed the importance of thyroid hormone-dependent signaling on intestinal tumor development and progression through action on stem cells. These results have a translational value, given that the thyroid hormone nuclear receptor TRα1 is upregulated in human CRCs, including in the molecular subtypes associated with CSC features. We used an established spheroid model generated from the human colon adenocarcinoma cell line Caco2 to study the effects of T3 and TRα1 on spheroid formation, growth, and response to conventional chemotherapies. Our results show that T3 treatment and/or increased TRα1 expression in spheroids impaired the response to FOLFIRI and conferred a survival advantage. This was achieved by stimulating drug detoxification pathways and increasing ALDH1A1-expressing cells, including CSCs, within spheroids. These results suggest that clinical evaluation of the thyroid axis and assessing TRα1 levels in CRCs could help to select optimal therapeutic regimens for patients with CRC. Proposed mechanism of action of T3/TRα1 in colon cancer spheroids. In the control condition, TRα1 participates in maintaining homeostatic cell conditions. The presence of T3 in the culture medium activates TRα1 action on target genes, including the drug efflux pumps ABCG2 and ABCB1. In the case of chemotherapy FOLFIRI, the increased expression of ABC transcripts and proteins induced by T3 treatment is responsible for the augmented efflux of 5-FU and Irinotecan from the cancer cells. Taken together, these mechanisms contribute to the decreased efficacy of the chemotherapy and allow cells to escape the treatment. Created with BioRender.com .

Characterization of a Human Respiratory Mucosa Model to Study Odorant Metabolism.

Nasal xenobiotic metabolizing enzymes (XMEs) are important for the sense of smell because they influence odorant availability and quality. Since the major part of the human nasal cavity is lined by a respiratory mucosa, we hypothesized that this tissue contributed to nasal odorant metabolism through XME activity. Thus, we built human respiratory tissue models and characterized the XME profiles using single-cell RNA sequencing. We focused on the XMEs dicarbonyl and l-xylulose reductase, aldehyde dehydrogenase (ALDH) 1A1, and ALDH3A1, which play a role in food odorant metabolism. We demonstrated protein abundance and localization in the tissue models and showed the metabolic activity of the corresponding enzyme families by exposing the models to the odorants 3,4-hexandione and benzaldehyde. Using gas chromatography coupled with mass spectrometry, we observed, for example, a significantly higher formation of the corresponding metabolites 4-hydroxy-3-hexanone (39.03 ± 1.5%, p = 0.0022), benzyl alcohol (10.05 ± 0.88%, p = 0.0008), and benzoic acid (8.49 ± 0.57%, p = 0.0004) in odorant-treated tissue models compared to untreated controls (0 ± 0, 0.12 ± 0.12, and 0.18 ± 0.18%, respectively). This is the first study that reveals the XME profile of tissue-engineered human respiratory mucosa models and demonstrates their suitability to study nasal odorant metabolism.

ALDH1A1 confers resistance to RAF/MEK inhibitors in melanoma cells by maintaining stemness phenotype and activating PI3K/AKT signaling.

The mitogen-activated protein kinase (MAPK/ERK) pathway is pivotal in controlling the proliferation and survival of melanoma cells. Several mutations, including those in BRAF, exhibit an oncogenic effect leading to increased cellular proliferation. As a result, the combination therapy of a MEK inhibitor with a BRAF inhibitor demonstrated higher efficacy and lower toxicity than BRAF inhibitor alone. This combination has become the preferred standard of care for tumors driven by BRAF mutations. Aldehyde dehydrogenase 1A1 (ALDH1A1) is a known marker of stemness involved in drug resistance in several type of tumors, including melanoma. This study demonstrates that melanoma cells overexpressing ALDH1A1 displayed resistance to vemurafenib and trametinib through the activation of PI3K/AKT signaling instead of MAPK axis. Inhibition of PI3K/AKT signaling partially rescued sensitivity to the drugs. Consistently, pharmacological inhibition of ALDH1A1 activity downregulated the activation of AKT and partially recovered responsiveness to vemurafenib and trametinib. We propose ALDH1A1 as a new potential target for treating melanoma resistant to MAPK/ERK inhibitors.

Aldehyde Dehydrogenese-1 High Cancer Stem-like Cells/Cancer-initiating Cells Escape from Cytotoxic T Lymphocytes due to Lower Expression of Human Leukocyte Antigen Class 1.

BACKGROUND/AIM: Human gastric cancer stem-like cells (CSCs)/cancer-initiating cells can be identified as aldehyde dehydrogenase-high (ALDHhigh) cells. Cancer immunotherapy employing immune checkpoint blockade has been approved for advanced gastric cancer cases. However, the effectiveness of cancer immunotherapy against gastric CSCs/CICs remains unclear. This study aimed to investigate the susceptibility of gastric CSCs/CICs to immunotherapy. MATERIALS AND METHODS: Gastric CSCs/CICs were isolated as ALDHhigh cells using the human gastric cancer cell line, MKN-45. ALDHhigh clone cells and ALDHlow clone cells were isolated using the ALDEFLUOR assay. ALDH1A1 expression was assessed via qRT-PCR. Sphere-forming ability was evaluated to confirm the presence of CSCs/CICs. A model neoantigen, AP2S1, was over-expressed in ALDHhigh clone cells and ALDHlow clone cells, and susceptibility to AP2S1-specific TCR-T cells was assessed using IFNγ ELISPOT assay. RESULTS: Three ALDHhigh clone cells were isolated from MKN-45 cells. ALDHhigh clone cells exhibited a stable phenotype in in vitro culture for more than 2 months. The High-36 clone cells demonstrated the highest sphere-forming ability, whereas the Low-8 cells showed the lowest sphere-forming ability. High-36 cells exhibited lower expression of HLA-A24 compared to Low-8 cells. TCR-T cells specific for AP2S1 showed lower reactivity to High-36 cells compared to Low-8 cells. CONCLUSION: High-36 cells and Low-8 cells represent novel gastric CSCs/CICs and non-CSCs/CICs, respectively. ALDHhigh CSCs/CICs evade T cells due to lower expression of HLA class 1.

Associations of Early-Life and Adult Anthropometric Measures with the Expression of Stem Cell Markers CD44, CD24, and ALDH1A1 in Women with Benign Breast Biopsies.

BACKGROUND: According to the stem cell hypothesis, breast carcinogenesis may be related to the breast stem cell pool size. However, little is known about associations of breast cancer risk factors, such as anthropometric measures, with the expression of stem cell markers in noncancerous breast tissue. METHODS: The analysis included 414 women with biopsy-confirmed benign breast disease in the Nurses' Health Study and Nurses' Health Study II. Birthweight, weight at age 18, current weight, and current height were reported via self-administered questionnaires. IHC staining of stem cell markers (CD44, CD24, and aldehyde dehydrogenase family 1 member A1) in histopathologically normal epithelial and stromal breast tissue was quantified using an automated computational image analysis system. Linear regression was used to examine the associations of early-life and adult anthropometric measures with log-transformed stem cell marker expression, adjusting for potential confounders. RESULTS: Birthweight [≥10.0 vs. <5.5 lbs: ß (95% confidence interval) = 4.29 (1.02, 7.56); P trend = 0.001 in the stroma] and adult height [≥67.0 vs. <63.0 inch: 0.86 (0.14, 1.58); P trend = 0.02 in the epithelium and stroma combined] were positively associated with CD44 expression. Childhood body fatness was inversely associated (P trend = 0.03) whereas adult height was positively associated with CD24 expression in combined stroma and epithelium (P trend = 0.03). CONCLUSIONS: Our data suggest that anthropometric measures, such as birthweight, adult height, and childhood body fatness, may be associated with the stem cell expression among women with benign breast disease. IMPACT: Anthropometric measures, such as birthweight, height, and childhood body fatness, may have long-term impacts on stem cell population in the breast.

Graphene Quantum Dots Eradicate Resistant and Metastatic Cancer Cells by Enhanced Interfacial Inhibition.

Drug-resistant and metastatic cancer cells such as a small population of cancer stem cells (CSCs) play a crucial role in metastasis and relapse. Conventional small-molecule chemotherapeutics, however, are unable to eradicate drug-resistant CSCs owing to limited interface inhibitory effects. Herein, it is reported that enhanced interfacial inhibition leading to eradication of drug-resistant CSCs can be dramatically induced by self-insertion of bioactive graphene quantum dots (GQDs) into DNA major groove (MAG) sites in cancer cells. Since transcription factors regulate gene expression at the MAG site, MAG-targeted GQDs exert greatly enhanced interfacial inhibition, downregulating the expression of a collection of cancer stem genes such as ALDH1, Notch1, and Bmi1. Moreover, the nanoscale interface inhibition mechanism reverses cancer multidrug resistance (MDR) by inhibiting MDR1 gene expression when GQDs are used at a nontoxic concentration (1/4 × half-maximal inhibitory concentration (IC50)) as the MDR reverser. Given their high efficacy in interfacial inhibition, CSC-mediated migration, invasion, and metastasis of cancer cells can be substantially blocked by MAG-targeted GQDs, which can also be harnessed to sensitize clinical cytotoxic agents for improved efficacy in combination chemotherapy. These findings elucidate the inhibitory effects of the enhanced nano-bio interface at the MAG site on eradicating CSCs, thus preventing cancer metastasis and recurrence.

Impaired spermatogenesis and associated endocrine effects of azole fungicides in peripubertal Xenopus tropicalis.

Early life exposure to endocrine disrupting chemicals (EDCs) has been suggested to adversely affect reproductive health in humans and wildlife. Here, we characterize endocrine and adverse effects on the reproductive system after juvenile exposure to propiconazole (PROP) or imazalil (IMZ), two common azole fungicides with complex endocrine modes of action. Using the frog Xenopus tropicalis, two short-term (2-weeks) studies were conducted. I: Juveniles (2 weeks post metamorphosis (PM)) were exposed to 0, 17 or 178 µg PROP/L. II: Juveniles (6 weeks PM) were exposed to 0, 1, 12 or 154 µg IMZ/L. Histological analysis of the gonads revealed an increase in the number of dark spermatogonial stem cells (SSCs)/testis area, and in the ratio secondary spermatogonia: dark SSCs were increased in all IMZ groups compared to control. Key genes in gametogenesis, retinoic acid and sex steroid pathways were also analysed in the gonads. Testicular levels of 3ß-hsd, ddx4 were increased and cyp19 and id4 levels were decreased in the IMZ groups. In PROP exposed males, increased testicular aldh1a2 levels were detected, but no histological effects observed. Although no effects on ovarian histology were detected, ovarian levels of esr1, rsbn1 were increased in PROP groups, and esr1 levels were decreased in IMZ groups. In conclusion, juvenile azole exposure disrupted testicular expression of key genes in retinoic acid (PROP) and sex steroid pathways and in gametogenesis (IMZ). Our results further show that exposure to environmental concentrations of IMZ disrupted spermatogenesis in the juvenile testis, which is a cause for concern as it may lead to impaired fertility. Testicular levels of id4, ddx4 and the id4:ddx4 ratio were associated with the number of dark SSCs and secondary spermatogonia suggesting that they may serve as a molecular markers for disrupted spermatogenesis.

Luminal B Breast Cancer Coexpressing p62 and ALDH1A3 Is Less Susceptible to Radiotherapy.

BACKGROUND/AIM: We have reported that p62 (also known as sequestosome 1) is needed for survival/proliferation and tumor formation by aldehyde dehydrogenase 1 (ALDH1) -positive cancer stem cells (CSCs) and that p62high ALDH1A3high expression is associated with a poor prognosis in luminal B breast cancer. However, the association between p62high ALDH1A3high and the benefit from radiotherapy in patients with luminal B breast cancer remains unclear. MATERIALS AND METHODS: Datasets from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and The Cancer Genome Atlas (TCGA) were downloaded, and data from p62high ALDH1A3high luminal B patients treated without or with radiotherapy were analyzed by Kaplan-Meier and multivariate Cox regression analyses. We also performed an in vitro tumor sphere formation assay after X-ray irradiation using p62-knockdown ALDH1high luminal B BT-474 cells. RESULTS: p62high ALDH1A3high patients had poorer clinical outcomes than other luminal B breast cancer patients treated with radiotherapy. The combination of p62 DsiRNA KD and X-ray irradiation suppressed in vitro tumor sphere formation by ALDH1high BT-474 cells. These results suggest that p62 is involved in the reduced effect of X-ray irradiation on ALDH1-positive luminal B breast CSCs. CONCLUSION: p62 and ALDH1A3 may serve as prognostic biomarkers for luminal B breast cancer patients treated with radiotherapy. Additionally, the combination of p62 inhibition and radiotherapy could be useful for targeted strategies against ALDH1-positive luminal B breast CSCs.