A Novel Role For Nanog As An Early Cancer Risk Marker In Patients With Laryngeal Precancerous Lesions

Secreted factors from M1 macrophages drive prostate cancer stem cell plasticity by upregulating NANOG, SOX2, and CD44 through NFκB-signaling

The inflammatory tumor microenvironment (TME) is a key driver for tumor-promoting processes. Tumor-associated macrophages are one of the main immune cell types in the TME and their increased density is related to poor prognosis in prostate cancer. Here, we investigated the influence of pro-inflammatory (M1) and immunosuppressive (M2) macrophages on prostate cancer lineage plasticity. Our findings reveal that M1 macrophage secreted factors upregulate genes related to stemness while downregulating genes associated with androgen response in prostate cancer cells. The expression of cancer stem cell (CSC) plasticity markers NANOG, KLF4, SOX2, OCT4, and CD44 was stimulated by the secreted factors from M1 macrophages. Moreover, AR and its target gene PSA were observed to be suppressed in LNCaP cells treated with secreted factors from M1 macrophages. Inhibition of NFκB signaling using the IKK16 inhibitor resulted in downregulation of NANOG, SOX2, and CD44 and CSC plasticity. Our study highlights that the secreted factors from M1 macrophages drive prostate cancer cell plasticity by upregulating the expression of CSC plasticity markers through NFκB signaling pathway.

Informed by Cancer Stem Cells of Solid Tumors: Advances in Treatments Targeting Tumor-Promoting Factors and Pathways

Cancer stem cells (CSCs) represent a subpopulation within tumors that promote cancer progression, metastasis, and recurrence due to their self-renewal capacity and resistance to conventional therapies. CSC-specific markers and signaling pathways highly active in CSCs have emerged as a promising strategy for improving patient outcomes. This review provides a comprehensive overview of the therapeutic targets associated with CSCs of solid tumors across various cancer types, including key molecular markers aldehyde dehydrogenases, CD44, epithelial cellular adhesion molecule, and CD133 and signaling pathways such as Wnt/β-catenin, Notch, and Sonic Hedgehog. We discuss a wide array of therapeutic modalities ranging from targeted antibodies, small molecule inhibitors, and near-infrared photoimmunotherapy to advanced genetic approaches like RNA interference, CRISPR/Cas9 technology, aptamers, antisense oligonucleotides, chimeric antigen receptor (CAR) T cells, CAR natural killer cells, bispecific T cell engagers, immunotoxins, drug-antibody conjugates, therapeutic peptides, and dendritic cell vaccines. This review spans developments from preclinical investigations to ongoing clinical trials, highlighting the innovative targeting strategies that have been informed by CSC-associated pathways and molecules to overcome therapeutic resistance. We aim to provide insights into the potential of these therapies to revolutionize cancer treatment, underscoring the critical need for a multi-faceted approach in the battle against cancer. This comprehensive analysis demonstrates how advances made in the CSC field have informed significant developments in novel targeted therapeutic approaches, with the ultimate goal of achieving more effective and durable responses in cancer patients.

Clinical significance of type IV vascularization of laryngeal lesions according to the Ni classification

Background

Scattered, small, dot-like intraepithelial papillary capillary loops (IPCLs) represent type IV epithelial vascularization according to "Ni classification" and are considered to be nonmalignant. According to the European Laryngological Society classification, these loops are malignant vascular changes. This contradiction has high clinical importance; therefore, clarification of the clinical significance of type IV vascularization according to the Ni classification is needed.

Methods

The study was performed between June 2015 and December 2022. All recruited patients (n = 434) were symptomatic, with macroscopic laryngeal lesions (n = 674). Patients were investigated using the enhanced endoscopic methods of narrow band imaging (NBI) and the Storz Professional Image Enhancement System (IMAGE1 S). The microvascular patterns in the lesions were categorized according to Ni classification from 2011 and all lesions were examined histologically.

Results

A total of 674 lesions (434 patients) were investigated using flexible NBI endoscopy and IMAGE1 S endoscopy. Type IV vascularization was recognized in 293/674 (43.5%) lesions. Among these 293 lesions, 178 (60.7%) were benign (chronic laryngitis, hyperplasia, hyperkeratosis, polyps, cysts, granulomas, Reinkeho oedema and recurrent respiratory papillomatosis); 9 (3.1%) were squamous cell carcinoma; 61 (20.8%) were mildly dysplastic, 29 (9.9%) were moderately dysplastic, 14 (4.8%) were severe dysplastic and 2 (0.7%) were carcinoma in situ. The ability to recognize histologically benign lesions in group of nonmalignant vascular pattern according to Ni (vascularization type I-IV) and distinguish them from precancers and malignancies was with accuracy 75.5%, sensitivity 54.4%, specificity 94.4%, positive predictive value 89.6% and negative predictive value 69.9%.

Conclusion

Laryngeal lesions with type IV vascularization as defined by Ni present various histological findings, including precancerous and malignant lesions. Patients with type IV vascularization must be followed carefully and, in case of progression mucosal lesion microlaryngoscopy and excision are indicated.

[Risk factors of recurrence and canceration for premalignant vocal fold lesions after surgery]

Objective:To analyze the risk factors of recurrence and canceration for premalignant vocal fold lesions after surgery, and to provide a reasonable basis for preoperative evaluation and postoperative follow-up. Methods:This study retrospective analyzed the relationship between clinicopathological factors and clinical outcome（recurrence, canceration, recurrence-free survival, and canceration-free survival） in 148 patients undergoing surgical treatment in Chongqing General Hospital from 2014 to 2017. Results:The five-year overall recurrence rate was 14.86% and the overall recurrence rate was 8.78%. Univariate analysis showed that smoking index, laryngopharyngeal reflux and lesion range were significantly associated with recurrence（P<0.05）, and smoking index and lesion range were significantly associated with canceration（P<0.05）. Multivariate logistic regression analysis showed that smoking index ≥600 and laryngopharyngeal reflux were independent risk factors for recurrence（P<0.05）, and smoking index ≥600 and lesion range ≥1/2 vocal cord were independent risk factors for canceration（P<0.05）. The mean carcinogenesis interval for the postoperative smoking cessation group was significantly longer（P<0.05）. Conclusion:Excessive smoking, laryngopharyngeal reflux and a wide range of lesions may be related to postoperative recurrence or malignant progression of precancerous lesions in the vocal cord, and further large-scale multi-center prospective randomized controlled studies are needed to clarify the effects of the above factors on recurrence and malignant changes in the future.

SUMOylation and the oncogenic E17K mutation affect AKT1 subcellular distribution and impact on Nanog-binding dynamics to chromatin in embryonic stem cells

AKT/PKB is a kinase involved in the regulation of a plethora of cell processes. Particularly, in embryonic stem cells (ESCs), AKT is crucial for the maintenance of pluripotency. Although the activation of this kinase relies on its recruitment to the cellular membrane and subsequent phosphorylation, multiple other post-translational modifications (PTMs), including SUMOylation, fine-tune its activity and target specificity. Since this PTM can also modify the localization and availability of different proteins, in this work we explored if SUMOylation impacts on the subcellular compartmentalization and distribution of AKT1 in ESCs. We found that this PTM does not affect AKT1 membrane recruitment, but it modifies the AKT1 nucleus/cytoplasm distribution, increasing its nuclear presence. Additionally, within this compartment, we found that AKT1 SUMOylation also impacts on the chromatin-binding dynamics of NANOG, a central pluripotency transcription factor. Remarkably, the oncogenic E17K AKT1 mutant produces major changes in all these parameters increasing the binding of NANOG to its targets, also in a SUMOylation dependent manner. These findings demonstrate that SUMOylation modulates AKT1 subcellular distribution, thus adding an extra layer of regulation of its function, possibly by affecting the specificity and interaction with its downstream targets.

Dysplastic Lesions of the Larynx

There have been many advancements in the clinical and histologic diagnosis of laryngeal dysplasia (LD), but diagnosis still necessitates invasive histologic evaluation. Furthermore, despite improved histologic identification of dysplastic lesions, the exact details of pathophysiologic progression and the risk of malignant transformation is still uncertain. These unknowns create a barrier to establishing an ideal grading and classification system, which prevents the establishment of a precise and consistent treatment paradigm. Identifying these gaps in knowledge serves to highlight where further studies are warranted, ideally focusing on a better understanding of the biological behavior of LD. This would ultimately allow for the creation of a reliable grading and classification system and for the formalization of management and treatment guidelines for LD.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Hypopharynx, Larynx, Trachea and Parapharyngeal Space

In this article, we review the chapter on tumors of the larynx, hypopharynx, trachea and parapharyngeal space in the new edition of the WHO book, focusing on the new developments in comparison to the previous edition. Squamous cell carcinoma (SCC) and its variants are by far the most common malignancies at these locations, with very limited new insights. The most important is the introduction of new targeted treatment-checkpoint inhibitors, with a new task for pathologists, who may help to predict the response to treatment by analyzing the expression of targeted proteins in biopsy samples. Precancerous lesions remain a controversial topic and, similarly to other organs, it is acceptable to use the terms "dysplasia" or "squamous intraepithelial lesion" (SIL), but there is a slight difference between low-grade dysplasia and low-grade SIL: in the former, mild atypia must be present, while the latter also includes hyperplastic epithelium without atypia. Two approaches have been proposed: a two-tiered system with low- and high-grade dysplasia/SIL and a three-tiered system with an additional category, carcinoma in situ. We are still searching for reliable diagnostic markers to surpass the subjectivity in biopsy diagnosis, with a few potential candidate markers on the horizon, e.g., stem cell markers. Other tumors are rare at these locations, e.g., hematolymphoid, neuroendocrine and salivary gland neoplasms, and are no longer included in Chapter 3. They must be diagnosed according to criteria described in specific chapters. The same holds true for soft tissue tumors, with the exception of cartilaginous neoplasms, which are still included in Chapter 3.

Qualitative and Quantitative Diagnosis in Head and Neck Cancer

The diagnosis is the art of determining the nature of a disease, and an accurate diagnosis is the true cornerstone on which rational treatment should be built. Within the workflow in the management of head and neck tumours, there are different types of diagnosis. The purpose of this work is to point out the differences and the aims of the different types of diagnoses and to highlight their importance in the management of patients with head and neck tumours. Qualitative diagnosis is performed by a pathologist and is essential in determining the management and can provide guidance on prognosis. The evolution of immunohistochemistry and molecular biology techniques has made it possible to obtain more precise diagnoses and to identify prognostic markers and precision factors. Quantitative diagnosis is made by the radiologist and consists of identifying a mass lesion and the estimation of the tumour volume and extent using imaging techniques, such as CT, MRI, and PET. The distinction between the two types of diagnosis is clear, as the methodology is different. The accurate establishment of both diagnoses plays an essential role in treatment planning. Getting the right diagnosis is a key aspect of health care, and it provides an explanation of a patient’s health problem and informs subsequent decision. Deep learning and radiomics approaches hold promise for improving diagnosis.

Nanog, in Cooperation with AP1, Increases the Expression of E6/E7 Oncogenes from HPV Types 16/18

Persistent infections with some types of human papillomavirus (HPV) constitute the major etiological factor for cervical cancer development. Nanog, a stem cell transcription factor has been shown to increase during cancer progression. We wanted to determine whether Nanog could modulate transcription of E6 and E7 oncogenes. We used luciferase reporters under the regulation of the long control region (LCR) of HPV types 16 and 18 (HPV16/18) and performed RT-qPCR. We found that Nanog increases activity of both viral regulatory regions and elevates endogenous E6/E7 mRNA levels in cervical cancer-derived cells. We demonstrated by in vitro mutagenesis that changes at Nanog-binding sites found in the HPV18 LCR significantly inhibit transcriptional activation. Chromatin immunoprecipitation (ChIP) assays showed that Nanog binds in vivo to the HPV18 LCR, and its overexpression increases its binding as well as that of c-Jun. Surprisingly, we observed that mutation of AP1-binding sites also affect Nanog's ability to activate transcription, suggesting cooperation between the two factors. We searched for putative Nanog-binding sites in the LCR of several HPVs and surprisingly found them only in those types associated with cancer development. Our study shows, for the first time, a role for Nanog in the regulation of E6/E7 transcription of HPV16/18.

Cancer of the Larynx and Hypopharynx

The Radiation Therapy Oncology Group 91-11 trial and US Veterans Affairs trial revolutionized the way locally advanced laryngeal cancers are treated. Adjuvant therapies exist aimed toward laryngeal preservation using docetaxel, cisplatin, and fluorouracil. Cetuximab is a cornerstone of treatment due to the large role of epidermal growth factor receptor in laryngeal and hypopharyngeal carcinomas. In addition, the immune system is vital in the prevention of recurrence, and various immunomodulators against programmed cell death receptor 1 are being investigated. Multidisciplinary management of the patient with laryngeal and hypopharyngeal is key, as many vital functions are affected by this devastating disease.

SUMO conjugation susceptibility of Akt/protein kinase B affects the expression of the pluripotency transcription factor Nanog in embryonic stem cells

Akt/PKB is a kinase involved in the regulation of a wide variety of cell processes. Its activity is modulated by diverse post-translational modifications (PTMs). Particularly, conjugation of the small ubiquitin-related modifier (SUMO) to this kinase impacts on multiple cellular functions, such as proliferation and splicing. In embryonic stem (ES) cells, this kinase is key for pluripotency maintenance. Among other functions, Akt is known to promote the expression of Nanog, a central pluripotency transcription factor (TF). However, the relevance of this specific PTM of Akt has not been previously analyzed in this context. In this work, we study the effect of Akt1 variants with differential SUMOylation susceptibility on the expression of Nanog. Our results demonstrate that both, the Akt1 capability of being modified by SUMO conjugation and a functional SUMO conjugase activity are required to induce Nanog gene expression. Likewise, we found that the common oncogenic E17K Akt1 mutant affected Nanog expression in ES cells also in a SUMOylatability dependent manner. Interestingly, this outcome takes places in ES cells but not in a non-pluripotent heterologous system, suggesting the presence of a crucial factor for this induction in ES cells. Remarkably, the two major candidate factors to mediate this induction, GSK3-β and Tbx3, are non-essential players of this effect, suggesting a complex mechanism probably involving non-canonical pathways. Furthermore, we found that Akt1 subcellular distribution does not depend on its SUMOylatability, indicating that Akt localization has no influence on the effect on Nanog, and that besides the membrane localization of E17K Akt mutant, SUMOylation is also required for its hyperactivity. Our results highlight the impact of SUMO conjugation in the function of a kinase relevant for a plethora of cellular processes, including the control of a key pluripotency TF.

Prognostic implication of SOX2 expression in small intestinal adenocarcinoma

The presence of KRAS mutation enhances the stem cell features of colorectal carcinoma cells containing mutant adenomatous polyposis coli (APC). However, their potential role in small intestinal adenocarcinoma remains elusive. Here, we aimed to investigate the clinical significance of cancer stem cell markers expression in the context of small intestinal adenocarcinoma with the KRAS genotype. SOX2, NANOG, and OCT4 expression were assessed by immunohistochemistry and digital image analysis, and their potential association with KRAS was further examined in 185 Korean patients with small intestinal adenocarcinomas, which were collected from 22 institutions in South Korea. Positive expression of SOX2, NANOG, and OCT4 was detected in 65 (35.1%), 94 (50.8%), and 82 (44.3%) of patients, respectively. Patients with high SOX2 (SOX2+) expression displayed worse overall survival compared to those with low SOX2 (SOX2-) expression (P < 0.001). Patients with SOX2+/mutant KRAS (KRAS^MT) (11.1 months) had significantly shorter overall survival than those with SOX2-/KRAS^WT (53.6 months) (P < 0.001). In multivariate analysis, SOX2+, distal location, high pT and pN categories, microsatellite stable, and absence of predisposing diseases were independent prognostic factors for worse overall survival. These results suggest that SOX2 expression has the potential to predict clinical outcomes in patients with small intestinal adenocarcinomas.

Reprogramming oral epithelial keratinocytes into a pluripotent phenotype for tissue regeneration

Objectives

We set out to reprogram adult somatic oral epithelial keratinocytes into pluripotent cells for regenerative dentistry.

Setting and Sample population

Immortalized murine oral keratinocyte cell (IMOK) line raised from adult mouse mucosa were cultured in vitro in our studies.

Materials and Methods

Adult murine oral epithelial keratinocytes were chronically treated with TGF‐β1 in vitro, and the expression of Oct4, Nanog, Sox2 and Nestin, as well as specific homeobox Gata and Pax gene family members were investigated.

Results

We documented the induction of stem factors linked with pluripotency and/or the maintenance and regulation of stem‐cell self‐renewal in oral epithelial keratinocytes by TGFβ1. Moreover, we discovered that this TGF‐β1‐induced increase in Oct4, Nanog, Sox2 and Nestin was inhibited by SB431542, suggesting that TGF‐β1 signals via the TGF‐βRI receptor to induce pluripotency and stemness.

Conclusions

Adult oral epithelial keratinocytes treated chronically with TGF‐β1 acquired phenotypic characteristics consistent with pluripotent stem cells, highlighting the facileness of reprogramming adult oral keratinocytes into an unlimited supply of pluripotent stem cells.

MicroRNAs and Long Non-Coding RNAs as Regulators of NANOG Expression in the Development of Oral Squamous Cell Carcinoma

NANOG is a stem cell transcription factor that is believed to play an important role in the development of oral squamous cell carcinoma (OSCC), but there is limited data regarding the role of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in the regulation of NANOG expression. We therefore analyzed expression of NANOG, NANOG-regulating miRNAs and lncRNAs in OSCC cancerogenesis, using oral biopsy samples from 66 patients including normal mucosa, dysplasia, and OSCC. Expression analysis of NANOG, miR-34a, miR-145, RoR, SNHG1, AB209630, and TP53 was performed using qPCR and immunohistochemistry for NANOG protein detection. NANOG protein showed no staining in normal mucosa, very weak in low-grade dysplasia, and strong staining in high-grade dysplasia and OSCC. NANOG, miR-145, RoR, and SNHG1 showed up-regulation, TP53 and miR-34a showed down-regulation, and AB209630 showed variable expression during cancerogenesis. NANOG mRNA was up-regulated early in cancerogenesis, before strong protein expression can be detected. NANOG was in correlation with miR-145 and RoR. Our results suggest that miRNAs and lncRNAs, particularly miR-145 and RoR, might be important post-transcription regulatory mechanisms of NANOG in OSCC cancerogenesis. Furthermore, NANOG protein detection has a diagnostic potential for oral high-grade dysplasia, distinguishing it from low-grade dysplasia and non-neoplastic reactive lesions.

European Laryngological Society position paper on laryngeal dysplasia Part II: diagnosis, treatment, and follow-up

PURPOSE OF REVIEW

To give an overview of the current knowledge regarding the diagnosis, treatment, and follow-up of laryngeal dysplasia (LD) and to highlight the contributions of recent literature. The diagnosis of LD largely relies on endoscopic procedures and on histopathology. Diagnostic efficiency of endoscopy may be improved using videolaryngostroboscopy (VLS) and bioendoscopic tools such as Narrow Band Imaging (NBI) or Storz Professional Image Enhancement System (SPIES). Current histological classifications are not powerful enough to clearly predict the risk to carcinoma evolution and technical issues such as sampling error, variation in epithelial thickness and inflammation hamper pathological examination. Almost all dysplasia grading systems are effective in different ways. The 2017 World Health Organization (WHO) system should prove to be an improvement as it is slightly more reproducible and easier for the non-specialist pathologist to apply. To optimize treatment decisions, surgeons should know how their pathologist grades samples and preferably audit their transformation rates locally. Whether carcinoma in situ should be used as part of such classification remains contentious and pathologists should agree with their clinicians whether they find this additional grade useful in treatment decisions. Recently, different studies have defined the possible utility of different biomarkers in risk classification. The main treatment modality for LD is represented by transoral laser microsurgery. Radiotherapy may be indicated in specific circumstances such as multiple recurrence or wide-field lesions. Medical treatment currently does not have a significant role in the management of LD. Follow-up for patients treated with LD is a fundamental part of their care and investigations may be supported by the same techniques used during diagnosis (VLS and NBI/SPIES).

Biomarkers for Malignant Potential in Vocal Fold Leukoplakia: A State of the Art Review

OBJECTIVE

To explore biomarkers that are candidates for understanding potential degeneration to malignancy of vocal fold leukoplakia (VFL), with the goal of guiding future diagnostic and treatment recommendations.

DATA SOURCES

PubMed and Medline search engines.

REVIEW METHODS

A systematic review was conducted by searching the following key words: vocal fold or laryngeal, coupled with leukoplakia or dysplasia, and combined with the term prognostic markers. We collated the biomarkers and their significance, followed by observing the power of their evidence by assessing the quality of the studies according to guidelines of tumor marker prognostic studies (REMARK).

CONCLUSIONS

Prognostic biomarkers in the 16 studies are generally divided into 3 categories according to their biological roles: proliferation (Ki-67, CK-1 RS14024 SNP), cell cycle control (P53, p16, cyclin D1, p57kip2, interleukin-10 [IL-10], miR-10a, and miR-34c), cell adhesion, and invasion (neutrophil-to-lymphocyte ratio, OPN/CD44v6 axis, MMP-1, vascular endothelial growth factor A, MMP-9, serpin peptidase inhibitor 1, plasminogen activator, CTNN/B1, β-catenin, NANOG, HERG1). The prognostic use of these biomarkers is limited due to the variable methodologies, study design, assay methods, and statistical analysis performed.

IMPLICATIONS FOR PRACTICE

Prognostic factors in vocal fold leukoplakia have important clinical implications regarding the potential for malignant degeneration. Although further study is needed, the currently available evidence suggests that p53, p16, cyclin D1, IL-10, NLR, OPN and CD44v6, CTNNB1, and CTTN and FAK might be of particular interest in determining prognosis of VFL as related to malignancy. Future, large, well-designed, prospective studies are expected to determine the prognostic power of these biomarkers before their implementation in routine clinical practice.

Expression of NANOG and Its Regulation in Oral Squamous Cell Carcinoma

Background

Results of previous studies suggest that NANOG may be an important prognostic biomarker in oral squamous cell carcinoma (OSCC), but there are contradictory results regarding NANOG expression patterns on mRNA and protein levels, and the mechanisms of its regulation are poorly understood. Our aim was to analyze the expression and diagnostic significance of NANOG in OSCC, and the possible mechanisms of its regulation, i.e., protein regulators on mRNA level (OCT4, SOX2, KLF4, AGR2, and NOTCH1), methylation status, copy number variation, and regulatory miRNAs, miR-145, miR-335, miR-150, miR-34a, miR-128, and miR-27a.

Methods

Our study included 120 patients with OSCC. Expression of NANOG protein and mRNA was analyzed using immunohistochemistry and qPCR. Expression of regulatory factors, miRNAs, and copy number variation was performed using qPCR. Methylation status of NANOG promoter was determined using PCR and Sanger sequencing.

Results

We detected upregulation of NANOG and OCT4 and downregulation of NOTCH1 and AGR2 mRNA in OSCC with lymph node metastases compared to OSCC without lymph node metastases. We observed a strong positive correlation between mRNAs of NANOG and those of its protein regulators OCT4, SOX2, NOTCH1, AGR2, and KLF4. The expression of NANOG was in positive correlation with the expression of miR-34a. There was also a correlation between T status of OSCC and the expression of miR-335 and miR-150 and a correlation of miR-150 with the N status of T2 OSCC. NANOG promoter methylation and copy number variation were only observed in a small proportion of samples.

Conclusions

Our findings confirm the diagnostic significance of NANOG in OSCC and provide information on NANOG expression patterns on both mRNA and protein levels. They also suggest that protein regulators and microRNAs might play a crucial role, whereas methylation of its promoter and copy number variation probably have a minor role in the regulation of NANOG expression in OSCC.

Prognostic Significance of the Pluripotency Factors NANOG, SOX2, and OCT4 in Head and Neck Squamous Cell Carcinomas

Cancer stem cells (CSCs) play major roles in tumor initiation, progression, and resistance to cancer therapy. Several CSC markers have been studied in head and neck squamous cell carcinomas (HNSCC), including the pluripotency factors NANOG, SOX2, and OCT4; however, their clinical significance is still unclear. NANOG, SOX2, and OCT4 expression was evaluated by immunochemistry in 348 surgically-treated HNSCC, and correlated with clinicopathological parameters and patient outcomes. mRNA expression was further analyzed in 530 The Cancer Genome Atlas (TCGA) HNSCC. NANOG protein expression was detected in 250 (72%) cases, more frequently in patients with lymph node metastasis (p = 0.003), and was an independent predictor of better survival in multivariate analysis. While OCT4 expression was undetectable, SOX2 expression was observed in 105 (30%) cases, and strongly correlated with NANOG expression. Combined expression of both proteins showed the highest survival rates, and double-negative cases the worst survival. Strikingly, the impact of NANOG and SOX2 on outcome varied depending on tumor site and lymph node infiltration, specifically showing prognostic significance in pharyngeal tumors. Correlation between NANOG and SOX2 at mRNA and protein was specifically observed in node positive (N+) patients, and consistently correlated with better survival rates. According to our findings, NANOG protein expression is frequent in HNSCC, thereby emerging as an independent predictor of better prognosis in pharyngeal tumors. Moreover, this study uncovers a differential impact of NANOG and SOX2 expression on HNSCC prognosis, depending on tumor site and lymph node infiltration, which could facilitate high-risk patient stratification.

Developing Classifications of Laryngeal Dysplasia: The Historical Basis

During the last 60 years numerous significant attempts have been made to achieve a widely acceptable terminology and histological grading for laryngeal squamous intraepithelial lesions. While dysplasia was included in the pathology of the uterine cervix already in 1953, the term dysplasia was accepted in laryngeal pathology first after the Toronto Centennial Conference on Laryngeal Cancer in 1974. In 1963 Kleinsasser proposed a three-tier classification, and in 1971 Kambic and Lenart proposed a four-tier classification. Since then, four editions of the World Health Organisation (WHO) classification have been proposed (1978, 1991, 2005 and 2017). Several terms such as squamous intraepithelial neoplasia (SIN) and laryngeal intraepithelial neoplasia (LIN) are now being abandoned and replaced by squamous intraepithelial lesions (SIL). The essential change between the 2005 and 2017 WHO classifications is the attempt to induce a simplification from a four- to a two-tier system. The current WHO classification (2017) thus recommends the use of a two-tier system with reasonably clear histopathological criteria for the two groups: low-grade and high-grade dysplasia. Problems with interobserver variability apart, subjectivities and uncertainties remain, but to a lesser degree. Ongoing and additional molecular studies may help to clarify underlying events that will increase our understanding and possibly can facilitate our attempts to obtain an even better classification. The classification needs to be easier for the general pathologist to perform and easier for the clinician to interpret. These two objectives are equally important to provide each patient the best personalised treatment available for squamous intraepithelial lesions.

Laryngeal Dysplasia: Persisting Dilemmas, Disagreements and Unsolved Problems-A Short Review

We present the historical review and current state of the histopathological classifications and terminology of laryngeal precursor lesions. Attention to recent genetic findings is also presented; although in need of additional confirmation, these raise possibility for early detection of patients at risk of dysplasia progression. Although a number of identified genetic alterations with a promising diagnostic and prognostic value are emerging, none of the known genetic alterations can be currently implemented in clinical practice as a completely reliable diagnostic and/or prognostic marker. Regarding the terminology of precursor lesions, dysplasia remains the most frequently used term, but squamous intraepithelial lesion can be used as a synonym as well. Histological findings, in spite of certain degree of subjectivity, remain at present the most reliable method for an accurate diagnosis. The current 2017 WHO classification seems to successfully stratify risk of malignant progression, with a significantly different risk of malignant progression between low-grade dysplasia and high-grade dysplasia. In case of pronounced architectural disorders, severe cellular and nuclear atypias, and an increased number of mitoses, also atypical form, the high-grade dysplasia and carcinoma in situ can be separated. The Slovenian tertiary centers have a policy of surgical removal of high-grade SILs and life-long close follow-up. Radiotherapy is reserved for more pronounced intraepithelial lesions classified as carcinoma in situ and invasive cancer. Such a distinction can facilitate clinical decision to use radiotherapy if complete surgical removal is not possible.

NANOG expression in human development and cancerogenesis

NANOG is an important stem cell transcription factor involved in human development and cancerogenesis. Its expression is complex and regulated on different levels. Moreover, NANOG protein might regulate hundreds of target genes at the same time. NANOG is crucial for preimplantation development phase and progressively decreases during embryonic stem cells differentiation, thus regulating embryonic and fetal development. Postnatally, NANOG is undetectable or expressed in very low amounts in the majority of human tissues. NANOG re-expression can be detected during cancerogenesis, already in precancerous lesions, with increasing levels of NANOG in high grade dysplasia. NANOG is believed to enable cancer cells to obtain stem-cell like properties, which are believed to be the source of expanding growth, tumor maintenance, metastasis formation, and tumor relapse. High NANOG expression in cancer is frequently associated with advanced stage, poor differentiation, worse overall survival, and resistance to treatment, and is therefore a promising prognostic and predictive marker. We summarize the current knowledge on the role of NANOG in cancerogenesis and development, including our own experience. We provide a critical overview of NANOG as a prognostic and diagnostic factor, including problems regarding its regulation and detection.

The Emerging Role of NANOG as an Early Cancer Risk Biomarker in Patients with Oral Potentially Malignant Disorders

NANOG, a key regulator of pluripotency and self-renewal in embryonic and adult stem cells, is frequently overexpressed in multiple cancers, including oral squamous cell carcinoma (OSCC). It has been frequently associated with poor outcomes in epithelial cancers, and recently implicated in laryngeal tumorigenesis. On this basis, we investigated the role of NANOG protein expression as an early cancer risk biomarker in oral potentially malignant disorders (OPMD), and the impact on prognosis and disease outcomes in OSCC patients. NANOG expression was evaluated by immunohistochemistry in 55 patients with oral epithelial dysplasia, and 125 OSCC patients. Correlations with clinical and follow-up data were assessed. Nuclear NANOG expression was detected in 2 (3.6%) and cytoplasmic NANOG expression in 9 (16.4%) oral dysplasias. NANOG expression increased with the grade of dysplasia. Cytoplasmic NANOG expression and the histopathological grading were significantly correlated with oral cancer risk, although dysplasia grading was the only significant independent predictor of oral cancer development in multivariate analyses. Cytoplasmic NANOG expression was also detected in 39 (31%) OSCC samples. Positive NANOG expression was significantly associated with tobacco and alcohol consumption, and was more frequent in pN0 tumors, early I-II stages. These data unveil the clinical relevance of NANOG in early stages of OSCC tumorigenesis rather than in advanced neoplastic disease. NANOG expression emerges as an early predictor of oral cancer risk in patients with OPMD.

MYCT1 represses apoptosis of laryngeal cancerous cells through the MAX/miR-181a/NPM1 pathway

MYCT1 is an important gene known to regulate cell viability and apoptosis of laryngeal cancer cells. However, the underlying molecular mechanism remains unclear. Here, we show that MAX enhances the expression of miR-181a by directly binding to its promoter, whereas miR-181a targets NPM1 and suppresses its expression in laryngeal cancer cells. MYCT1 and miR-181a decrease cell viability and colony formation through enhanced apoptosis, whereas NPM1 displays opposite effects in laryngeal cancer cells. Their opposing functions are further supported by the findings (a) that miR-181a is down-regulated, while NPM1 is up-regulated in laryngeal cancer, and (b) that either inhibition of miR-181a or overexpression of NPM1 can revert the pro-apoptotic effects of MYCT1 on laryngeal cancer cells through extracellular and intracellular apoptotic pathways. Our data suggest that MYCT1 may synergistically interact with MAX as a co-transcription factor or a component of MAX transcriptional complex, to transcriptionally regulate the expression of miR-181a, which, in turn, decreases NPM1 expression at post-transcriptional levels, leading to enhanced apoptosis in laryngeal cancer cells. These factors may serve as potential targets for early diagnosis and treatment of laryngeal cancer.

The Novel Role of SOX2 as an Early Predictor of Cancer Risk in Patients with Laryngeal Precancerous Lesions

The SOX2 gene located at 3q26 is frequently amplified and overexpressed in multiple cancers, including head and neck squamous cell carcinomas (HNSCC). The tumor-promoting activity and involvement of SOX2 in tumor progression has been extensively demonstrated, thereby emerging as a promising therapeutic target. However, the role of SOX2 in early stages of tumorigenesis and its possible contribution to malignant transformation remain unexplored. This study investigates for the first time SOX2 protein expression by immunohistochemistry and gene amplification by real-time PCR using a large series of 94 laryngeal precancerous lesions. Correlations with the histopathological classification and the risk of progression to invasive carcinoma were established. Nuclear SOX2 expression was frequently detected in 38 (40%) laryngeal dysplasias, whereas stromal cells and normal adjacent epithelia showed negative expression. SOX2 gene amplification was detected in 18 (33%) of 55 laryngeal dysplasias. Univariate Cox analysis showed that SOX2 gene amplification (p = 0.046) and protein expression (p < 0.001) but not histological grading (p = 0.432) were significantly associated with laryngeal cancer risk. In multivariate stepwise analysis including age, tobacco, histology, SOX2 gene amplification and SOX2 expression, SOX2 expression (HR = 3.531, 95% CI 1.144 to 10.904; p = 0.028) was the only significant independent predictor of laryngeal cancer development. These findings underscore the relevant role of SOX2 in early tumorigenesis and a novel clinical application of SOX2 expression as independent predictor of laryngeal cancer risk in patients with precancerous lesions beyond current WHO histological grading. Therefore, targeting SOX2 could lead to effective strategies for both cancer prevention and treatment.

Differential sequences of exosomal NANOG DNA as a potential diagnostic cancer marker

NANOG has been demonstrated to play an essential role in the maintenance of embryonic stem cells, and its pseudogene, NANOGP8, is suggested to promote the cancer stem cell phenotype. As the roles of these genes are intimately involved with glioblastoma multiforme progression and exosomes are critical in intercellular communication, we conducted a detailed analysis of the association of the NANOG gene family with exosomes to identify diagnostic markers for cancer. Exosomes were precipitated from conditioned culture media from various cell lines, and NANOG gene fragments were directly amplified without DNA isolation using multiple primer sets. The use of the enzymes AlwNI and SmaI with restriction fragment length polymorphism analysis functioned to distinguish NANOGP8 from other NANOG family members. Collectively, results suggest that the NANOG DNA associated with exosomes is not full length and that mixed populations of the NANOG gene family exist. Furthermore, sequence analysis of exosomal DNA amplified with a NANOGP8 specific primer set frequently showed an insertion of a 22 bp sequence into the 3’ UTR. The occurrence rate of this insertion was significantly higher in exosomal DNA clones from cancer cells as compared to normal cells. We have detected mixed populations of NANOG DNA associated with exosomes and have identified preferential modulations in the sequences from cancer samples. Our findings, coupled with the properties of exosomes, may allow for the detection of traditionally inaccessible cancers (i.e. GBM) through minimally invasive techniques. Further analysis of exosomal DNA sequences of NANOG and other embryonic stemness genes (OCT3/4, SOX2, etc.) may establish a robust collection of exosome based diagnostic markers, and further elucidate the mechanisms of cancer formation, progression, and metastasis.

Aggressive Phenotype of Cells Disseminated via Hematogenous and Lymphatic Route in Breast Cancer Patients

Intratumoral heterogeneity of breast cancer remains a major challenge in successful treatment. Failure of cancer therapies can also be accredited to inability to systemically eradicate cancer stem cells (CSCs). Recent evidence points to the role of epithelial-mesenchymal transition (EMT) in expanding the pool of tumor cells with CSCs features. Thus, we assessed expression level as well as heterogeneity of CSCs markers in primary tumors (PT), lymph node metastasis (LNM), and circulating tumor cells (CTCs)-enriched blood fractions in order to correlate them with signs of EMT activation as well as clinicopathological data of breast cancer patients. Level of CSCs markers (ALDH1, CD44, CD133, OCT-4, NANOG) and EMT markers was quantified in PT (N=107), LNM (N=56), and CTCs-enriched blood fractions (N=85). Heterogeneity of CSCs markers expression within each PT and LNM was assessed by calculating Gini Index. Percentage of ALDH1-positive cells was elevated in PT in comparison to LNM (P = .005). However, heterogeneity of the four CSCs markers: ALDH1 (P = .019), CD133 (P = .009), OCT-4 (P = .027), and CD44 (P < .001) was decreased in LNM. Samples classified as mesenchymal (post-EMT) showed elevated expression of CSCs markers (OCT-4 and CD44 in PT; OCT-4 in LNM; ALDH1, OCT-4, NANOG, CD44 in CTCs). Patients with mesenchymal-like CTCs had worse prognosis than patients with epithelial-like or no CTCs (P = .0025). CSCs markers are enriched in PT, LNM, and CTCs with mesenchymal features, but their heterogeneity is decreased in metastatic lymph nodes. Mesenchymal CTCs phenotype correlates with poor prognosis of the patients.