BACKGROUND: Stem cells have been associated with self-renewing and plasticity and have been investigated in various odontogenic lesions in association with their pathogenesis and biological behavior. We aim to provide a systematic review of stem cell markers\' expression in odontogenic tumors and cysts.
METHODS: The literature was searched through the MEDLINE/PubMed, EMBASE via OVID, Web of Science, and CINHAL via EBSCO databases for original studies evaluating stem cell markers\' expression in different odontogenic tumors/cysts, or an odontogenic disease group and a control group. The studies\' risk of bias (RoB) was assessed via a Joanna Briggs Institute Critical Appraisal Tool. Meta-analysis was conducted for markers evaluated in the same pair of odontogenic tumors/cysts in at least two studies.
RESULTS: 29 studies reported the expression of stem cell markers, e.g., SOX2, OCT4, NANOG, CD44, ALDH1, BMI1, and CD105, in various odontogenic lesions, through immunohistochemistry/immunofluorescence, polymerase chain reaction, flow cytometry, microarrays, and RNA-sequencing. Low, moderate, and high RoBs were observed in seven, nine, and thirteen studies, respectively. Meta-analysis revealed a remarkable discriminative ability of SOX2 for ameloblastic carcinomas or odontogenic keratocysts over ameloblastomas.
CONCLUSIONS: Stem cells might be linked to the pathogenesis and clinical behavior of odontogenic pathologies and represent a potential target for future individualized therapies.

The signet-ring cell variant of squamous cell carcinoma (SCC) is an extremely rare histological subtype, with only 24 cases (including the present case) reported in the Medline database: 15 affecting the external surface of the body, 3 in the lung, 2 affecting the uterine cervix, 1 involving the gingiva, another one affecting the esophagus and the present case that is the first reported at the gastro-esophageal junction (GEJ). In one case, the location of the lesion was not mentioned. A 59-year-old male patient underwent segmental eso-gastrectomy for carcinoma of the GEJ. The microscopic examination showed a pT3N1-staged SCC composed of solid nests admixed in over 30% of the tumor, with cells having eccentrically located nuclei and clear vacuolated cytoplasm. The signet-ring cells did not show mucinous secretion and were positive for keratin 5/6 and vimentin, with nuclear expression of β-catenin and Sox2 and focal membrane positivity for E-cadherin. Based on these features, the case was considered a signet-ring SCC with epithelial-mesenchymal transition. Thirty-one months after surgery, the patient was disease-free, with no local recurrence and no known distant metastases. In SCC, a signet-ring cell component might be an indicator of the dedifferentiation of tumor cells towards a mesenchymal molecular subtype.

OBJECTIVE: Prognostic biomarkers in cervical cancer are widely investigated, including cancer stem cell (CSC) markers. However, their significance remains uncertain. This study aimed to determine the role of cervical cancer stem cell (CCSC) markers for survival.
METHODS: We conducted a systematic review and meta-analysis (PROSPERO CRD42021237072) of studies reporting CCSC markers as the prognostic predictor based on PRISMA guidelines. We included English articles investigating associations of CCSCs expression in tissue tumor with overall survival (OS) or disease-free survival (DFS) from PubMed, EBSCO, and The Cochrane Library databases. The quality of studies was analyzed based on Newcastle-Ottawa Quality Assessment Scale.
RESULTS: From 413 publications, after study selection with inclusion and exclusion criteria, 22 studies were included. High expressions of CCSC markers were associated with poor OS and DFS (HR= 1.05, 95% CI: 1.03 - 1.07, P <0.0001; HR= 1.31, 95% CI: 1.09 - 1.17, P <0.00001; respectively). Sub-analysis of individual CCSC markers indicated significant correlations between CD44 (HR= 1.14, 95% CI: 1.07 - 1.22, P 0.0001), SOX2 (HR= 1.58, 95% CI: 1.17 - 2.14, P 0.003), OCT4 (HR= 1.03, 95% CI: 1.01 - 1.06, P 0.008), ALDH1 (HR= 1.36, 95% CI: 1.13 - 1.64, P 0.001), and CD49f (HR= 3.02, 95% CI: 1.37 - 6.64, P 0.006) with worse OS; OCT4 (HR= 1.14, 95% CI 1.06 - 1.22, P 0.0003), SOX2 (HR= 1.11, 95% CI: 1.06 - 1.16, P <0.0001), and ALDH1 (HR= 1.22, 95% CI: 1.10 - 1.35, P 0.0002) with poor DFS. We did not conduct a meta-analysis for MSI-1 and CK17 because only one study investigated those markers.
CONCLUSIONS: Expressions of OCT4, SOX2, and ALDH1 were associated with poor OS and DFS in cervical cancer tissue. These markers might have potential roles as prognostic biomarkers to predict unfavorable survival.

SOX2 variants and deletions are a common cause of anophthalmia and microphthalmia (A/M). This article presents data from a cohort of patients with SOX2 variants, some of whom have been followed for 20+ years. Medical records from patients enrolled in the A/M Research Registry and carrying SOX2 variants were reviewed. Thirty-seven patients were identified, ranging in age from infant to 30 years old. Eye anomalies were bilateral in 30 patients (81.1%), unilateral in 5 (13.5%), and absent in 2 (5.4%). Intellectual disability was present in all with data available and ranged from mild to profound. Seizures were noted in 18 of 27 (66.6%) patients, usually with abnormal brain MRIs (10/15, 66.7%). Growth issues were reported in 14 of 21 patients (66.7%) and 14 of 19 (73.7%) had gonadotropin deficiency. Genitourinary anomalies were seen in 15 of 19 (78.9%) male patients and 5 of 15 (33.3%) female patients. Patients with SOX2 nucleotide variants, whole gene deletions or translocations are typically affected with bilateral or unilateral microphthalmia and anophthalmia. Other associated features include intellectual disability, seizures, brain anomalies, growth hormone deficiency, gonadotropin deficiency, and genitourinary anomalies. Recommendations for newly diagnosed patients with SOX2 variants include eye exams, MRI of the brain and orbits, endocrine and neurology examinations. Since the clinical spectrum associated with SOX2 alleles has expanded beyond the originally reported phenotypes, we propose a broader term, SOX2-associated disorder, for this condition.

Extragonadal germ cell tumors (EGGCTs) are uncommon neoplasms, which arise in anatomical locations other than gonads. The pathogenesis of these neoplasms is still poorly understood and it is a matter of debate if they really represent extragondal primary neoplasms or rather extragondal metastasis from occult gonadal neoplasms. The actual observations suggest that EGGCTs represent a unique entity, so their biology and behavior are substantially different from gonadal counterparts. The diagnosis of EGGCTs is often challenging, and differential diagnosis is particularly wide. Nevertheless, a correct diagnosis is essential for the correct management of the patient. We summarize the state of art about EGGCTs, with particular emphasis on diagnosis and prognosis.

Up to now, the prognosis of non-small cell lung cancer (NSCLC) is poor. With progress of cancer biology, a number of genes have been investigated for predicting prognosis of NSCLC, such as cancer stem cell markers SRY (sex determining region Y)-box 2 (SOX2) and Nestin. Recently, a series of studies have been performed to examine the associations of SOX2 and Nestin with clinical parameters and prognosis in NSCLC, however, the results were not consistent. In the present study, we conducted a systematic review and meta-analysis to summarize the associations. Four English databases (PubMed, ISI web of science, Embase, and Ovid) were used to search the relevant studies with the last date of November 10, 2015. The pooling analyses were stratified by DNA amplification and protein expression. The pooling ORs or HRs were used to assess the strength of the associations. Finally, we included 19 articles for SOX2 and six articles for Nestin according to the inclusion and exclusion criteria. The pooling analyses revealed that there were significant associations between SOX2 DNA amplification and clinical features of NSCLC, gender, smoking status, squamous cell cancer (SCC) histology, and differentiations. And significant associations were also identified between SOX2 protein expression and clinical parameters, smoking status and SCC histology. For Nestin, its protein expression was correlated with lymph node metastasis and stage. Simultaneously, we found that high/positive SOX2 alterations, either DNA amplification or protein expression, were favorable for overall survival (OS) in NSCLC. On the contrary, high/positive Nestin protein expression was poor for OS.

The existence of tissue-specific progenitor/stem cells in the adult pituitary gland of the mouse has been demonstrated recently using genetic tracing experiments. These cells have the capacity to differentiate into all of the different cell lineages of the anterior pituitary and self-propagate in vitro and can therefore contribute to normal homeostasis of the gland. In addition, they play a critical role in tumor formation, specifically in the etiology of human adamantinomatous craniopharyngioma, a clinically relevant tumor that is associated with mutations in CTNNB1 (gene encoding β-catenin). Mouse studies have shown that only pituitary embryonic precursors or adult stem cells are able to generate tumors when targeted with oncogenic β-catenin, suggesting that the cell context is critical for mutant β-catenin to exert its oncogenic effect. Surprisingly, the bulk of the tumor cells are not derived from the mutant progenitor/stem cells, suggesting that tumors are induced in a paracrine manner. Therefore, the cell sustaining the mutation in β-catenin and the cell-of-origin of the tumors are different. In this review, we will discuss the in vitro and in vivo evidence demonstrating the presence of stem cells in the adult pituitary and analyze the evidence showing a potential role of these stem cells in pituitary tumors.

Lung cancer is the leading cause of cancer-related mortality worldwide. Diagnosis of lung cancer in an early stage is still a challenge due to the asymptomatic course of early stages of the disease and the lack of a standard screening program for the population. Nowadays, learning about the mechanisms that lead to cancerogenesis in the lung is crucial for the development of new diagnostic and therapeutic strategies. Recently, many studies have proved that cancer stem cells (CSCs) are responsible for the initiation, progression, metastasis, recurrence, and even resistance of chemo- and radiotherapeutic treatment in patients with lung cancer. The expression of pluripotency transcription factors is responsible for stemness properties. In this review, we summarize the current knowledge on the role of CSCs and pluripotency transcription factors in lung carcinogenesis.