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.

CD44 and ALDH1 immunoexpression as prognostic indicators of invasion and metastasis in oral squamous cell carcinoma.

BACKGROUND: Tumour metastasis has been associated with cancer stem cells, a small population with stem-like cells properties, higher rate of migration and metastatic potential compared to cells from the tumour bulk. Our aim was to evaluate the immunoexpression of the putative cancer stem cell biomarkers ALDH1 and CD44 in primary tumour and corresponding metastatic lymph nodes. METHODS: Tumour tissue specimens (n = 50) and corresponding metastatic lymph nodes (n = 25) were surgically obtained from 50 patients with oral squamous cell carcinoma and submitted to immunohistochemistry. CD44 and ALDH1 were semi-quantitatively scored according to the proportion and intensity of positive cells within the invasive front and metastatic lymph nodes as a whole. A combined score was obtained by multiplying both parameters and later dichotomized into a final score classified as low (≤2) or high (>2) immunoexpression. RESULTS: ALDH1 immunoexpression and CD44 immunoexpression were detected in both tumour sites, although the means of ALDH1 (P = .0985) and CD44 (P = .4220) cells were higher in metastasis compared to primary tumours. ALDH1high was positively associated (P = .0184) with angiolymphatic invasion, while CD44high was positively associated (P = .0181) with metastasis (N+). At multivariate analysis, CD44 significantly increased the odds of lymph node metastasis, regardless of T stage (OR = 8.24; 1.64-65.64, P = .0088). CONCLUSIONS: CD44 immunoexpression was a significant predictor of lymph node metastasis, while ALDH1high immunostaining was associated with angiolymphatic invasion. Altogether, it suggests that immunoexpression of CD44 and ALDH1 links the cancer stem cell phenotype with oral squamous cell carcinoma invasion and metastasis.

Expression of cancer stem cell markers CD44, ALDH1 and p75NTR in actinic cheilitis and lip cancer.

PURPOSE: The aim of this work was to evaluate the expression of the cancer stem cell (CSC) markers CD44, ALDH1 and p75NTR in the ultraviolet-induced lesions actinic cheilitis (AC) and lip squamous cell carcinoma (LSCC), and to correlate it with p53 expression. METHODS: Immunohistochemistry was performed in 4 cases of normal lip (NL), 43 of AC and 20 of LSCC. RESULTS: All cases were positive for CD44, showing a membranous staining without differences between the groups. ALDH1 showed cytoplasmic staining and it was invariable amongst the grades of epithelial dysplasia and between AC and LSCC. p75NTR presented membranous/cytoplasmic staining in the basal and parabasal layer of NL and AC, while LSCC presented cytoplasmic staining in the peripheral layers of the tumor islands. p75NTR showed different expression amongst the dysplasia grades (p < 0.001) but no differences between AC and LSCC. p53 expression was similar amongst the dysplasia grades and between AC and LSCC. CD44, ALDH1 and p75NTR were unrelated amongst themselves and to p53 expression. CONCLUSIONS: CSC markers are expressed in potentially malignant and malignant lesions of the lip. Their expressions were invariable between AC and LSCC and unrelated to p53. p75NTR expression increased with the worsening of epithelial dysplasia grade.

Expression of stem cell markers in oral cavity and oropharynx squamous cell carcinoma.

OBJECTIVES: The aim of this study was to analyze the expression of CD24, CD44, CD133, ALDH1, CD29 (integrin-ß1), and Ki-67 in squamous cell carcinoma of the oral cavity and oropharynx. STUDY DESIGN: Fifty-two tumors and 21 metastatic lymph nodes were evaluated by using immunohistochemistry. RESULTS: Seven of 52 cases (13.5%) showed positive cytoplasmic staining of aldehyde dehydrogenase 1; integrin-ß1 was expressed in 45 of 50 cases (90%); 30 of 52 cases (57.7%) had positive membranous staining of CD44; CD24 was expressed in 44 of 50 cases (88%); and three of 52 cases (5.8%) stained positively for membranous CD133. Median proliferation rate, measured by Ki-67, was 37.1% for tumors. Five-year cancer-specific survival rates for the CD44-negative and CD44-positive groups were 74% and 38%, respectively, although this difference did not reach statistical significance (P = .052). CONCLUSIONS: Our study demonstrated the expression of putative stem cell markers in squamous cell carcinoma of the oral cavity and oropharynx, with participation of CD44-positive cells in association with poor survival outcome.

Snail-induced epithelial-mesenchymal transition in gastric carcinoma cells and generation of cancer stem cell characteristics.

Biological changes in Snail-overexpressed SGC7901 cells were studied by establishing a pEGFP-C1-Snail carrier. The significance of Snail in epithelial-mesenchymal transition (EMT) as well as the invasion and metastatic capacity of gastric cancer cells was also discussed; moreover, we attempted to verify the probable cancer stem cell characteristics of Snail-overexpressed cells. A pEGFP-C1-Snail eukaryotic expression plasmid was constructed and pEGFP-C1(-) and pEGFP-C1-Snail plasmids were extracted and transfected into SGC7901 cells using Lipofectamine 2000. Stably expressed SGC7901-N [control group containing pEGFP-C1(-)] and SGC7901-S (test group containing pEGFP-C1-Snail) cells were screened using a G418 resistance medium. Snail, E-cadherin, b-catenin, vimentin, and fibronectin gene and protein expressions were detected by real-time quantitative PCR, western blot, and immunofluorescence. Cell invasion and metastasis were tested by scratch test, invasion assay, and an adhesion experiment. The positive rate of aldehyde dehydrogenase-1 (ALDH-1) expression was analyzed by flow cytometry. The results indicated the occurrence of EMT, accompanied by morphological changes in the cells and a weakening of the cell adhesion capacity. We also observed a decrease in the expression of epithelial markers E-cadherin and b-catenin and an increase in mesenchymal (Snail and vimentin) marker expression. Moreover, the cells showed increased invasiveness and metastatic capacity, and decreased proliferative ability. Moreover, the Snail-treated SGC7901 cells moved towards the scratch and produced fewer clones compared to the control cells. Owing to its capacity for self-renewal, SGC7901-S cells produced new clones and expressed ALDH-1. Therefore, we concluded that Snail overexpression induced EMT and endowed cells with tumor stem cell characteristics.

The dental pulp stem cell niche based on aldehyde dehydrogenase 1 expression.

AIM: To detect cells expressing the stem cell marker ALDH1 (aldehyde dehydrogenase1) in the pulp of human permanent teeth and to investigate the expression of ALDH1 in isolated dental pulp cells. METHODOLOGY: Pulp tissue was collected and processed for immunohistochemistry to detect ALDH1-, STRO-1- and CD90-positive cells. In addition, cells were isolated and analysed by flow cytometry for ALDH1 activity and for the cell surface markers CD44, CD73, CD90, STRO-1 and CD45. Cells were also examined for multidifferentiation capacity. Within these cells, an ALDH1(+) cell subpopulation was selected and evaluated for multidifferentiation capacity. RESULTS: The immunohistochemistry analyses showed that ALDH1-, CD90- and STRO-1-positive cells were located mainly in the perivascular areas and nerve fibres of dental pulps. Cells on the fifth passage had high expression for CD44, CD73 and CD90, whereas moderate labelling was observed for STRO-1 and ALDH1 in flow cytometry analysis. On the same passages, cells were able to differentiate into osteogenic, adipogenic and chondrogenic lineages. The ALDH1(+) cell subpopulation also demonstrated multilineage differentiation ability. CONCLUSIONS: Dental pulp stem cells reside in the vicinity of blood vessels and nerve fibres, indicating the possible existence of more than one stem cell niche in dental pulps. Furthermore, ALDH1 was expressed by isolated dental pulp cells, which had mesenchymal stem cell characteristics. Thus, it can be suggested that ALDH1 may be used as a DPSC marker.

Ethanol modulates the synthesis and catabolism of retinoic acid in the rat prostate.

All-trans retinoic acid (atRA) maintains physiological stability of the prostate, and we reported that ethanol intake increases atRA in the rat prostate; however the mechanisms underlying these changes are unknown. We evaluated the impact of a low- and high-dose ethanol intake (UChA and UChB strains) on atRA metabolism in the dorsal and lateral prostate. Aldehyde dehydrogenase (ALDH) subtype 1A3 was increased in the dorsal prostate of UChA animals while ALDH1A1 and ALDH1A2 decreased in the lateral prostate. In UChB animals, ALDH1A1, ALDH1A2, and ALDH1A3 increased in the dorsal prostate, and ALDH1A3 decreased in the lateral prostate. atRA levels increased with the low activity of CYP2E1 and decreased with high CYP26 activity in the UChB dorsal prostate. Conversely, atRA was found to decrease when the activity of total CYP was increased in the UChA lateral prostate. Ethanol modulates the synthesis and catabolism of atRA in the prostate in a concentration-dependent manner.

Prevalencia de intento de suicidio adolescente y factores de riesgo asociados en una comuna rural de la provincia de Concepción / Suicide attempts among Chilean adolescents

Background: Suicide mortality rates are increasing among teenagers. Aim: To study the prevalence and predictive factors of suicide attempts among Chilean adolescents. Material and Methods: A random sample of 195 teenagers aged 16 ± 1 years (53% males) answered an anonymous survey about their demographic features, substance abuse, the Osaka suicidal ideation questionnaire, Smilksten familial Apgar. Beck hopelessness scale, Beck depression scale and Coppersmith self-esteem inventory. Results: Twenty five percent of respondents had attempted suicide at least in one occasion during their lives. These attempts were significantly associated with female gender, absent parents, family dysfunction, drug abuse, smoking, low self-esteem, hopelessness, depression and recent suicidal ideation. A logistic regression analysis accepted female gender, smoking and recent suicidal ideation as significant independent predictors of suicide attempt. Conclusions: Suicide attempted is common among teenagers and its predictors are female sex, smoking and previous suicidal ideation.

Retinaldehyde dehydrogenase activity is triggered during allograft rejection and it drives Th1/Th17 cytokine production.

Retinoic acid (RA), a vitamin A metabolite, has been attributed to relevant functions in adaptive immunity. On T cells, the disruption on RA signaling alters both CD4+ and CD8+ T cells effector function. In this study, we evaluated the contribution of RA synthesis during the immune response using an in vivo skin transplantation model. Our data indicates that the frequency and number of cells containing an active retinaldehyde dehydrogenase (RALDH), a key enzyme for RA synthesis, is increased during skin transplant rejection. In addition, we found that the expression of the mRNA coding for the isoform RALDH2 is up-regulated on graft rejecting draining lymph nodes (dLNs) cells. Lastly, we observed that IFN-γ and IL-17 production by ex vivo re-stimulated dLNs cells is greatly increased during rejection, which it turns depends on RA synthesis, as shown in experiments using a specific RALDH inhibitor. Altogether, our data demonstrate that RA synthesis is incremented during the immune response against an allograft, and also indicates that the synthesis of RA is required for cytokine production by dLNs resident T cells.

Aldehyde dehydrogenases in early stage lung cancer: nuclear expression.

PURPOSE: Aldehyde dehydrogenase enzymes are a family of intracellular enzymes that participate in cellular detoxification, differentiation and drug resistance through the oxidation of cellular aldehydes. The isoform 1 (ALDH1) has been proved useful for the identification of cancer stem cells. The ALDH1 cytoplasmatic expression has been associated with poor prognostis in several tumours, such as non-small cell lung cancer. The role of the ALDH1 nuclear expression remains unknown. METHODS: We conducted a historical cohort study in 89 patients diagnosed of stage I non-small cell lung cancer treated with surgery between 2009 and 2004 in the Thoracic Surgery Department in the Universitary Hospital Puerta de Hierro. We selected from this sample those cases with nuclear expression of the ALDH1. RESULTS: Three of the 89 (3.3 %) patients showed a nuclear expression of the ALDH1. The three of them are still alive with a median time of follow up of 73 months (more than 6 years). CONCLUSION: We have identified ALDH1 as a nuclear protein in early stage non-small cell lung cancer. It might have a function in cell cycle control, associating a better prognosis to these patients. More studies are necessary to clarify the role of nuclear expression of ALDH1.

Levels of the retinoic acid synthesizing enzyme aldehyde dehydrogenase-1A2 are lower in testicular tissue from men with infertility.

OBJECTIVE: To determine whether decreased testicular levels of enzymes necessary for retinoic acid biosynthesis were associated with male infertility, as retinoic acid is known to be necessary for spermatogenesis. DESIGN: Observational analysis of testicular tissue samples, sperm indices, and serum hormone concentrations. SETTING: Two infertility centers in Chile. PATIENT(S): 32 infertile men and 11 control men. INTERVENTION(S): Measurement of the three enzymes necessary for retinoic acid biosynthesis, aldehyde dehydrogenase (ALDH) 1A1, 1A2, and 1A3, in testicular tissue by a novel liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) peptide assay. MAIN OUTCOME MEASURE(S): ALDH isozyme levels compared by type of infertility and correlated with testicular germ cell numbers, sperm parameters, and serum and intratesticular hormone concentrations. RESULT(S): Men with infertility had statistically significantly reduced levels of ALDH1A2 but not ALDH1A1 or ALDH1A3 in their testicular tissue compared with men with normal spermatogenesis. The ALDH1A2 protein levels were strongly correlated with the number of germ cells found via testicular biopsy. CONCLUSION(S): These findings suggest that ALDH1A2 is the enzyme involved in retinoic acid biosynthesis in human germ cells. Further study of the relationship between intratesticular ALDH1A2 and male infertility is warranted to determine whether men with infertility have a reduced ability to synthesize retinoic acid within their germ cells that could impair spermatogenesis.

Parasite infections in multiple sclerosis modulate immune responses through a retinoic acid-dependent pathway.

We recently demonstrated better outcomes in helminth-infected multiple sclerosis (MS) patients, compared with uninfected ones. The present study evaluates the role of TLR2 and retinoic acid (RA) in parasite-driven protection in MS patients. RA serum levels were significantly higher in helminth-infected MS patients than in uninfected MS subjects or healthy controls. Genes involved in RA biosynthesis and metabolism, such as Adh1 and Raldh2, as well as RA receptors and IL-10, were induced in dendritic cells (DCs) via TLR2-dependent ERK signaling. This programmed DCs to induce FOXP3(+) T regulatory cells and suppressed production of proinflammatory cytokines (IL-6, IL-12, IL-23, and TNF-α) via induction of suppressor of cytokine signaling 3 (SOCS3), an effect mediated by soluble egg Ag (SEA) obtained from Schistosoma mansoni, and by RA. SEA-activated DCs also inhibited IL-17 and IFN-γ production through autoreactive T cells. These inhibitory effects were abrogated when SOCS3 gene expression was silenced, indicating that SEA-mediated signaling inhibited production of these cytokines by T cells, through a SOCS3-dependent pathway. Overall, helminth-related immunomodulation observed in MS patients was mediated by TLR2- and RA-dependent pathways, through two different mechanisms, as follows: 1) induction of IL-10 and FOXP3(+) T regulatory cells, and 2) suppression of proinflammatory cytokine production mediated by SOCS3.

Prognostic impact of the cancer stem cell related markers ALDH1 and EZH2 in triple negative and basal-like breast cancers.

AIMS: We assessed the expression of ALDH1 and EZH2, cancer stem cell (CSC) related markers, in triple negative and basal-like breast cancers, investigating their association with clinicopathological features and outcome. METHODS: Clinicopathological data were obtained from 140 cases of triple negative breast cancer. A tissue microarray was constructed and immunohistochemistry for ER, PR, HER2, ALDH1, EZH2, CK5, CK14, EGFR, p63, caveolin, and p53 was performed. Tumour cell and stromal expression of ALDH1 were evaluated. Multivariate analysis was conducted, including all significant variables. RESULTS: The majority of triple negative breast cancers were invasive ductal carcinomas of no special type (NST) (116/140). Tumour cells exhibited cytoplasmic expression of ALDH1 in 26 of 140 cases, while stromal expression was detected in 117 of 140 cases. Tumour cell expression did not correlate with any of the parameters. Conversely, stromal expression was associated with better overall survival (p=0.044). Assessment by Cox Regression Model showed a HR of 2.80 (HR = 1/0.357 = 2.80; 95%CI 0.178-0.714; p = 0.004) for breast cancer death when ALDH1 was not found in the stromal compartment of tumours, independent of age, histological type/grade, nodal status, stage, relapse, and expression of basal markers. High EZH2 expression was noted in 120 of 140 triple negative breast cancers and was not associated with other variables. Basal-like cancers comprised 75% (105/140) of triple negative breast cancers. Interestingly, we found association between EZH2 and CK14 expression (p = 0.041). CONCLUSIONS: ALDH1 expression is frequent in tumour-associated stromal cells of triple negative breast cancer and is associated with better outcome. Tumour microenvironment should be considered when studying prognostic impact of CSCs in breast cancer.

High expression of retinoic acid receptors and synthetic enzymes in the human hippocampus.

Retinoic acid, the active form of the nutrient vitamin A, regulates several facets of neuronal plasticity in the hippocampus, including neurogenesis and synaptic strength, acting via specific retinoic acid receptors (RARs). Essential for conversion of vitamin A to retinoic acid is the enzyme retinaldehyde dehydrogenase (RALDH) and in the rodent hippocampus this is only present in the adjacent meninges where it must act as a locally released paracrine hormone. Little is known though about the expression of RALDHs and RARs in the human hippocampus. This study confirms that RALDH levels are very low in mouse neurons but, surprisingly, strong expression of RALDH protein is detected by immunohistochemistry in hippocampal neurons. The receptors RARα, ß and γ were also detected, each receptor exhibiting differing subcellular locations implying their potential regulation of both transcription and non-genomic actions. These results imply an essential function of retinoic acid in the human hippocampus likely to include regulation of neuronal plasticity.

Retinoic acid modulates retinaldehyde dehydrogenase 1 gene expression through the induction of GADD153-C/EBPbeta interaction.

Mammalian class I aldehyde dehydrogenase (ALDH) plays an important role in the biosynthesis of the hormone retinoic acid (RA), which modulates gene expression and cell differentiation. RA has been shown to mediate control of human ALDH1 gene expression through modulation of the retinoic acid receptor alpha (RARalpha) and the CCAAT/enhancer binding protein beta (C/EBPbeta). The positive activation of these transcription factors on the ALDH1 promoter is inhibited by RA through a decrease of C/EBPbeta binding to the ALDH1 CCAAT box response element. However, the mechanism of this effect remains unknown. Here we report that the RARalpha/retinoid X receptor beta (RXRbeta) complex binds to the mouse retinaldehyde dehydrogenase 1 (Raldh1) promoter at a non-consensus RA response element (RARE) with similar affinity to that of the consensus RARE. We found that C/EBPbeta binds to a Raldh1 CCAAT box located at -82/-58bp, adjacent to the RARE. Treatment with RA increases GADD153 and GADD153-C/EBPbeta interaction resulting in a decreased cellular availability of C/EBPbeta for binding to the Raldh1 CCAAT box. These data support a model in which high RA levels inhibit Raldh1 gene expression by sequestering C/EBPbeta through its interaction to GADD153.