Polygenic sex determination in vertebrates - is there any such thing?

Genetic sex determination (SD) in most vertebrates is controlled by a single master sex gene, which ensures a 1:1 sex ratio. However, more complex systems abound, and several have been ascribed to polygenic SD (PSD), in which many genes at different loci interact to produce the sexual phenotype. Here we examine claims for PSD in vertebrates, finding that most constitute transient states during sex chromosome turnover, or aberrant systems in species hybrids. To avoid confusion about terminology, we propose a consistent nomenclature for genetic SD systems.

Biased precursor ingression underlies the center-to-pole pattern of male sex determination in mouse.

During mammalian development, gonadal sex determination results from the commitment of bipotential supporting cells to Sertoli or granulosa cell fates. Typically, this decision is coordinated across the gonad to ensure commitment to a single organ fate. When unified commitment fails in an XY mouse, an ovotestis forms in which supporting cells in the center of the gonad typically develop as Sertoli cells, while supporting cells in the poles develop as granulosa cells. This central bias for Sertoli cell fate was thought to result from the initial expression of the drivers of Sertoli cell fate, SRY and/or SOX9, in the central domain, followed by paracrine expansion to the poles. However, we show here that the earliest cells expressing SRY and SOX9 are widely distributed across the gonad. In addition, Sertoli cell fate does not spread among supporting cells through paracrine relay. Instead, we uncover a center-biased pattern of supporting cell precursor ingression that occurs in both sexes and results in increased supporting cell density in the central domain. Our findings prompt a new model of gonad patterning in which a density-dependent organizing principle dominates Sertoli cell fate stabilization.

Inefficient Sox9 upregulation and absence of Rspo1 repression lead to sex reversal in the B6.XYTIR mouse gonad†.

Sry on the Y-chromosome upregulates Sox9, which in turn upregulates a set of genes such as Fgf9 to initiate testicular differentiation in the XY gonad. In the absence of Sry expression, genes such as Rspo1, Foxl2, and Runx1 support ovarian differentiation in the XX gonad. These two pathways antagonize each other to ensure the development of only one gonadal sex in normal development. In the B6.YTIR mouse, carrying the YTIR-chromosome on the B6 genetic background, Sry is expressed in a comparable manner with that in the B6.XY mouse, yet, only ovaries or ovotestes develop. We asked how testicular and ovarian differentiation pathways interact to determine the gonadal sex in the B6.YTIR mouse. Our results showed that (1) transcript levels of Sox9 were much lower than in B6.XY gonads while those of Rspo1 and Runx1 were as high as B6.XX gonads at 11.5 and 12.5 days postcoitum. (2) FOXL2-positive cells appeared in mosaic with SOX9-positive cells at 12.5 days postcoitum. (3) SOX9-positive cells formed testis cords in the central area while those disappeared to leave only FOXL2-positive cells in the poles or the entire area at 13.5 days postcoitum. (4) No difference was found at transcript levels of all genes between the left and right gonads up to 12.5 days postcoitum, although ovotestes developed much more frequently on the left than the right at 13.5 days postcoitum. These results suggest that inefficient Sox9 upregulation and the absence of Rspo1 repression prevent testicular differentiation in the B6.YTIR gonad.

SOX4 silencing alleviates renal injury in rats with acute renal failure by inhibiting the NF-κB signaling pathway and reducing apoptosis and oxidative stress.

Acute renal failure (ARF) is a huge threat to the lives of most patients in intensive care units, and there is currently no satisfactory treatment strategy. SRY-box transcription factor 4 (SOX4) plays a key role in the development of various diseases, but its effect on ARF is unknown. Therefore, this study aimed to explore the relationship between SOX4 and ARF. Blood samples were collected from 20 ARF patients and 20 healthy volunteers. We also established an ARF rat model by excising the right kidney and ligating the left renal artery, and SOX4 knockdown in ARF rats was achieved down by means of lentiviral infection. Subsequently, we used quantitative polymerase chain reaction and western bolt assays to detect the expression levels of SOX4 and nuclear factor-κB (NF-κB) signaling pathway-related proteins in human blood or rat renal tissue and hematoxylin and eosin and terminal deoxynucleotidyl transferase (TdT) 2'-deoxyuridine 5'-triphosphate (dUTP) nick-end labeling staining to observe the pathological changes and apoptosis of renal tissue. Enzyme-linked immunosorbent assay and biochemical kits were used to measure the levels of renal function-related indicators (blood urea nitrogen, creatinine, and neutrophil gelatinase-associated lipocalin) and inflammatory factors (interleukin [IL]-1ß, IL-6, and tumor necrosis factor-alpha), as well as changes in oxidative stress-related indicators (malondialdehyde [MDA], superoxide dismutase [SOD], and reactive oxygen species [ROS]) in rat serum. SOX4 expression levels in blood samples from ARF patients and renal tissue from ARF rats were significantly higher compared with those in healthy volunteers and control rats, respectively. ARF model rats displayed the typical ARF phenotype, while SOX4 silencing significantly improved pathological injury and apoptosis of renal tissue in ARF rats. Moreover, SOX4 silencing significantly inhibited increased levels of renal function-related indicators and inflammatory factors and reduced the level of excessive oxidative stress (MDA and ROS were upregulated, and SOD was downregulated) in ARF rats. SOX4 also reduced the activity of the NF-κB signaling pathway in ARF samples. Thus, SOX4 knockdown may reduce oxidative stress, the inflammatory response, and apoptosis by reducing the activity of the NF-κB signaling pathway, thereby improving renal injury in ARF rats.

Unusual sex chromosomal DSD in a domestic Shorthair cat with a 37,X/38,XY mosaic karyotype.

BACKGROUND: Sex chromosome abnormalities associated with disorders of sexual development (DSD) are rarely described in cats, mainly due to the lack of chromossome studies that precisely reveal the condition. Genetic approaches are therefore required in order to detect sex chromossomes abnormalities as variations in the number and structure of chromosomes, or the presence of a second cell line as mosaicim or chimerism. CASE PRESENTATION: A male Shorthair cryptorchid cat was presented with clinical signs of anorexia, tenesmus and hyperthermia. Ultrasonography revealed a fluid-filled structure, with approximately 1 cm in diameter, adjacent to the descending colon. Computed tomography evidenced a tubular structure, ventral to the descending colon and caudal to the bladder, which extended cranially, through two branches. Histopathological evaluation confirmed the presence of two atrophic uterine horns and one hypoplastic testicle with epididymis at the end of one of the uterine horns. The end of the other uterine horn was attached to a structure composed by a mass of adipocytes. Cytogenetic analysis revealed a mosaic 37,X/38,XY karyotype. The two cell lines were found in 15% and 85% of the lymphocytes, respectively. Genetic analysis confirmed the presence of SRY and ZFY genes in blood and hair bulbs, and revealed a marked reduction in SRY expression in the testicle. Additionally, this case presented exceptionally rare features, such as a Leydig' cell tumour and a chronic endometritis in both uterine horns. CONCLUSIONS: Complete imaging workup, cytogenetic analysis and SRY gene expression should be systematically realized, in order to properly classify disorders of sexual development (DSD) in cats.

SOX17 Deficiency Mediates Pulmonary Hypertension: At the Crossroads of Sex, Metabolism, and Genetics.

Rationale: Genetic studies suggest that SOX17 (SRY-related HMG-box 17) deficiency increases pulmonary arterial hypertension (PAH) risk. Objectives: On the basis of pathological roles of estrogen and HIF2α (hypoxia-inducible factor 2α) signaling in pulmonary artery endothelial cells (PAECs), we hypothesized that SOX17 is a target of estrogen signaling that promotes mitochondrial function and attenuates PAH development via HIF2α inhibition. Methods: We used metabolic (Seahorse) and promoter luciferase assays in PAECs together with the chronic hypoxia murine model to test the hypothesis. Measurements and Main Results: Sox17 expression was reduced in PAH tissues (rodent models and from patients). Chronic hypoxic pulmonary hypertension was exacerbated by mice with conditional Tie2-Sox17 (Sox17EC-/-) deletion and attenuated by transgenic Tie2-Sox17 overexpression (Sox17Tg). On the basis of untargeted proteomics, metabolism was the top pathway altered by SOX17 deficiency in PAECs. Mechanistically, we found that HIF2α concentrations were increased in the lungs of Sox17EC-/- and reduced in those from Sox17Tg mice. Increased SOX17 promoted oxidative phosphorylation and mitochondrial function in PAECs, which were partly attenuated by HIF2α overexpression. Rat lungs in males displayed higher Sox17 expression versus females, suggesting repression by estrogen signaling. Supporting 16α-hydroxyestrone (16αOHE; a pathologic estrogen metabolite)-mediated repression of SOX17 promoter activity, Sox17Tg mice attenuated 16αOHE-mediated exacerbations of chronic hypoxic pulmonary hypertension. Finally, in adjusted analyses in patients with PAH, we report novel associations between a SOX17 risk variant, rs10103692, and reduced plasma citrate concentrations (n = 1,326). Conclusions: Cumulatively, SOX17 promotes mitochondrial bioenergetics and attenuates PAH, in part, via inhibition of HIF2α. 16αOHE mediates PAH development via downregulation of SOX17, linking sexual dimorphism and SOX17 genetics in PAH.

Molecular Pathways and Animal Models of Tricuspid Atresia and Univentricular Heart.

The process of valve formation is a complex process that involves intricate interplay between various pathways at precise times. Although we have not completely elucidated the molecular pathways that lead to normal valve formation, we have identified a few major players in this process. We are now able to implicate TGF-ß, BMP, and NOTCH as suspects in tricuspid atresia (TA), as well as their downstream targets: NKX2-5, TBX5, NFATC1, GATA4, and SOX9. We know that the TGF-ß and the BMP pathways converge on the SMAD4 molecule, and we believe that this molecule plays a very important role to tie both pathways to TA. Similarly, we look at the NOTCH pathway and identify the HEY2 as a potential link between this pathway and TA. Another transcription factor that has been implicated in TA is NFATC1. While several mouse models exist that include part of the TA abnormality as their phenotype, no true mouse model can be said to represent TA. Bridging this gap will surely shed light on this complex molecular pathway and allow for better understanding of the disease process.

Neural Crest.

This chapter discusses the role of cardiac neural crest cells in the formation of the septum that divides the cardiac arterial pole into separate systemic and pulmonary arteries. Further, cardiac neural crest cells directly support the normal development and patterning of derivatives of the caudal pharyngeal arches, including the great arteries, thymus, thyroid, and parathyroids. Recently, cardiac neural crest cells have also been shown to indirectly influence the development of the secondary heart field, another derivative of the caudal pharynx, by modulating signaling in the pharynx. The contribution and function of the cardiac neural crest cells has been learned in avian models; most of the genes associated with cardiac neural crest function have been identified using mouse models. Together these studies show that the neural crest cells may not only critical for normal cardiovascular development but also may be involved secondarily because they represent a major component in the complex tissue interactions in the caudal pharynx and outflow tract. Cardiac neural crest cells span from the caudal pharynx into the outflow tract, and therefore may be susceptible to any perturbation in or by other cells in these regions. Thus, understanding congenital cardiac outflow malformations in human sequences of malformations resulting from genetic and/or environmental insults necessarily requires better understanding the role of cardiac neural crest cells in cardiac development.

Knockout of the HMG domain of the porcine SRY gene causes sex reversal in gene-edited pigs.

The sex-determining region on the Y chromosome (SRY) is thought to be the central genetic element of male sex development in mammals. Pathogenic modifications within the SRY gene are associated with a male-to-female sex reversal syndrome in humans and other mammalian species, including rabbits and mice. However, the underlying mechanisms are largely unknown. To understand the biological function of the SRY gene, a site-directed mutational analysis is required to investigate associated phenotypic changes at the molecular, cellular, and morphological level. Here, we successfully generated a knockout of the porcine SRY gene by microinjection of two CRISPR-Cas ribonucleoproteins, targeting the centrally located "high mobility group" (HMG), followed by a frameshift mutation of the downstream SRY sequence. This resulted in the development of genetically male (XY) pigs with complete external and internal female genitalia, which, however, were significantly smaller than in 9-mo-old age-matched control females. Quantitative digital PCR analysis revealed a duplication of the SRY locus in Landrace pigs similar to the known palindromic duplication in Duroc breeds. Our study demonstrates the central role of the HMG domain in the SRY gene in male porcine sex determination. This proof-of-principle study could assist in solving the problem of sex preference in agriculture to improve animal welfare. Moreover, it establishes a large animal model that is more comparable to humans with regard to genetics, physiology, and anatomy, which is pivotal for longitudinal studies to unravel mammalian sex determination and relevant for the development of new interventions for human sex development disorders.

Impaired communication ability in SOX11 syndrome.

BACKGROUND: Speech and language skills are important for social interaction and learning. This study characterised the communication abilities of verbal individuals with SOX11 syndrome using a standardised parent/carer questionnaire, the Children's Communication Checklist (CCC-2). METHOD: Thirteen parent/carers of verbal individuals (aged 5-19 years) diagnosed with SOX11 syndrome completed the CCC-2. In order to contextualise findings, responses were compared to norms and to data from Noonan syndrome, a relatively well-known genetic diagnosis associated with communication impairment. RESULTS: For all individuals, the CCC-2 composite score indicated significant communication difficulties. Language structure (speech, syntax, semantics and coherence), pragmatic language (inappropriate initiation, stereotyped language use of context and non-verbal communication) and autistic features (social relations and interests) scores were lower than typically developing norms. Subscale comparisons revealed relative difference in use of context compared to other pragmatic domains (stereotyped language and inappropriate initiation). Individual scores showed substantial variation, particularly in regard to language structure profile. Differences were more pronounced than for Noonan syndrome, specifically in domains of speech, syntax, non-verbal communication and social relations. CONCLUSIONS: SOX11 syndrome is associated with communication impairment. It is important to assess communication abilities as part of the management of individuals with SOX11 syndrome and understand individual strengths and difficulties in order to provide targeted support.

Clinical and genetic characteristics of disorders of sex development in Sudanese patients

Given the scarce data on DSD in Sudan, we aimed to characterize DSD's clinical and genetic profile in Sudanese patients. We studied 60 patients with DSD using clinical data, cytogenetics, and PCR for the SRY gene. The results showed that 65% grew up as females and 35% as males. There was a high percentage of consanguineous parents (85%). Female genital mutilation (FGM) was performed in 75% of females. Patients who presented after pubertal age were 63%, with ambiguous genitalia in 61.7%, followed by primary amenorrhea (PA) in 30%. The SRY gene was positive in 3.3% of patients with 46,XX karyotype and negative in 6.7% of patients with 46,XY karyotype. 5αR2D-DSD was seen in 43.3%, gonadal dysgenesis in 21.7%, Ovotesticular syndrome in 6.7%, Swyer and Turner syndrome in 5% each, and Androgen Insensitivity Syndrome (AIS) in 3.3%. In conclusion, DSD in Sudan has a distinct profile with late presentation, dominated by 5αR2D-DSD due to the increased consanguineous marriage, and FGM represents a significant risk for DSD patients.

Compte tenu du peu de données sur le DSD au Soudan, nous avons cherché à caractériser le profil clinique et génétique du DSD chez les patients soudanais. Nous avons étudié 60 patients atteints de DSD en utilisant des données cliniques, cytogénétiques et PCR pour le gène SRY. Les résultats ont montré que 65 % ont grandi en tant que femmes et 35 % en tant qu'hommes. Il y avait un pourcentage élevé de parents consanguins (85 %). Des mutilations génitales féminines (MGF) ont été pratiquées chez 75 % des femmes. Les patientes qui se sont présentées après l'âge pubertaire étaient 63 %, avec des organes génitaux ambigus dans 61,7 %, suivis d'une aménorrhée primaire (AP) dans 30 %. Le gène SRY était positif chez 3,3 % des patients de caryotype 46,XX et négatif chez 6,7 % des patients de caryotype 46,XY. Le 5αR2D-DSD a été observé dans 43,3 %, la dysgénésie gonadique dans 21,7 %, le syndrome ovotesticulaire dans 6,7 %, le syndrome de Swyer et Turner dans 5 % chacun et le syndrome d'insensibilité aux androgènes (AIS) dans 3,3 %. En conclusion, le DSD au Soudan présente un profil distinct avec une présentation tardive, dominé par le 5αR2D-DSD en raison de l'augmentation des mariages consanguins, et les MGF représentent un risque important pour les patients DSD.

[Genetic and clinical characteristics of 46,XX testicular disorders of sex development].

OBJECTIVE: To investigate the genetic and clinical characteristics of 46, XX testicular disorders of sex development (DSD). METHODS: We collected the clinical data on the patients with 46,XX testicular DSD diagnosed in the Center of Reproductive Medicine of the First Affiliated Hospital of Nanjing Medical University from January 2017 to January 2023, and analyzed their genetic and clinical characteristics and the SRY gene chromosomal location for those with SRY-positive. RESULTS: A total of 26 patients were included in this study, all with 46,XX and deletion of the AZFa, b and c regions, with a mean height of (168.3±5.9) cm, body weight of (64.0±7.5) kg, BMI of (22.66±2.79) kg/m2, left testis volume of (2.53±1.16) ml and right testis volume of (2.74±1.34) ml. The semen volume of the patients averaged 1.35 (0.18－2.78) ml, FSH (36.85±18.01) IU/L, LH (19.71±9.71) IU/L, and T (6.08±2.71) nmol/L. The SRY-negative patients had a higher incidence rate of development disorders in the reproductive system than the SRY-positive ones (5/6 vs 3/20, P = 0.004), but no statistically significant differences were observed in the other parameters. The SRY gene was localized at the end of Xp in 13 of the 14 SRY-positive cases, and at chromosome 15 in the other 1. CONCLUSION: 46,XX testicular DSD has some similarity and heterogeneity in genetics and clinical characteristics.

ROR2 deficit may induce the tetralogy of Fallot via down-regulating of ß-catenin/SOX3/HSPA6 in vitro and in vivo.

Tetralogy of Fallot (TOF) is the highly conventional appearance of cyanotic congenital heart disease. Our study aimed to assess the involvement of receptor tyrosine kinase-like orphan receptor 2 (ROR2) in TOF and elucidate the specific mechanism. Upon investigation of human tissue samples, we observed a decrease in ROR2 expression in TOF patients compared to healthy control individuals. Transcriptome analysis revealed diminished ROR2 expression in TOF pathological samples relative to normal tissues. Of the 2246 genes that exhibited altered expression, 886 were upregulated, while 1360 were down-regulated. KEGG analysis and GO analysis of the differentially expressed genes indicated that these genes were significantly enriched in the Wnt signalling pathway, apoptosis and cardiac development function. Importantly, ROR2 was the only gene shared among the three pathways. Furthermore, interference with ROR2 promotes apoptosis and curtails cell proliferation in vitro. The knockdown of the ROR2 gene in AC16 cells resulted in a significant decrease in Edu-positive cells. Flow cytometry studies indicated an increase in the percentage of cells in the S phase. In contrast, the G2/M cell cycle transition was blocked in the ROR2-knockdown group, leading to a significant increase in apoptosis. Moreover, the CCK-8 cell viability assay demonstrated a reduced proliferation in the ROR2-knockdown group. Furthermore, both in vivo and in vitro data indicated that the expression of HSPA6 (Recombinant Heat Shock 70 kDa Protein6), an essential gene enriched in cardiac tissue and associated with apoptosis, was down-regulated following ROR2 knockdown mediated by the ß-catenin/SOX3 signalling pathway. In conclusion, low expression of ROR2 plays a crucial role in the occurrence and development of TOF, which may be related to the downregulation of HSPA6 through the ß-catenin/SOX3 signalling pathway.

Transforming growth factor-ß challenge alters the N-, O-, and glycosphingolipid glycomes in PaTu-S pancreatic adenocarcinoma cells.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by poor prognosis and high mortality. Transforming growth factor-ß (TGF-ß) plays a key role in PDAC tumor progression, which is often associated with aberrant glycosylation. However, how PDAC cells respond to TGF-ß and the role of glycosylation therein is not well known. Here, we investigated the TGF-ß-mediated response and glycosylation changes in the PaTu-8955S (PaTu-S) cell line deficient in SMA-related and MAD-related protein 4 (SMAD4), a signal transducer of the TGF-ß signaling. PaTu-S cells responded to TGF-ß by upregulating SMAD2 phosphorylation and target gene expression. We found that TGF-ß induced expression of the mesenchymal marker N-cadherin but did not significantly affect epithelial marker E-cadherin expression. We also examined differences in N-glycans, O-glycans, and glycosphingolipid-linked glycans in PaTu-S cells upon TGF-ß stimulation. TGF-ß treatment primarily induced N-glycome aberrations involving elevated levels of branching, core fucosylation, and sialylation in PaTu-S cells, in agreement with TGF-ß-induced changes in the expression of glycosylation-associated genes. In addition, we observed differences in O glycosylation and glycosphingolipid glycosylation profiles after TGF-ß treatment, including lower levels of sialylated Tn antigen and neoexpression of globosides. Furthermore, the expression of transcription factor sex-determining region Y-related high-mobility group box 4 was upregulated upon TGF-ß stimulation, and its depletion blocked TGF-ß-induced N-glycomic changes. Thus, TGF-ß-induced N-glycosylation changes can occur in a sex-determining region Y-related high-mobility group box 4-dependent and SMAD4-independent manner in the pancreatic PaTu-S cancer cell line. Our results open up avenues to study the relevance of glycosylation in TGF-ß signaling in SMAD4-inactivated PDAC.

Differential activity of transcription factor Sox9 in early and adult oligodendroglial progenitor cells.

The high-mobility-group domain-containing transcription factor Sox9 confers glial competence to neuroepithelial precursors in the developing central nervous system and is an important determinant of astroglial and oligodendroglial specification. In oligodendroglial cells, it remains expressed in oligodendrocyte progenitor cells (OPCs) of the developing nervous system, but is shut off in differentiating oligodendrocytes as well as in OPCs that persist in the adult nervous system. To better understand the role of Sox9 in OPCs, we generated mouse models that allowed oligodendroglial expression of a Sox9 transgene during development or in the adult. With transgene expression beginning in the last trimester of pregnancy, the number of OPCs increased dramatically, followed by comparable gains in the number of pre-myelinating and myelinating oligodendrocytes as assessed by marker gene expression. This argues that Sox9 boosts oligodendrogenesis during ontogenetic development at all stages, including terminal oligodendrocyte differentiation. When Sox9 transgene expression started in the adult, many transgene-expressing OPCs failed to maintain their progenitor cell identity and instead converted into myelinating oligodendrocytes. As infrequent and inefficient differentiation of adult OPCs is one of the main obstacles to effective remyelination in demyelinating diseases such as Multiple Sclerosis, increased Sox9 levels in adult OPCs may substantially increase their remyelination capacity.

The injury-induced transcription factor SOX9 alters the expression of LBR, HMGA2, and HIPK3 in the human kidney.

Induction of SRY box transcription factor 9 (SOX9) has been shown to occur in response to kidney injury in rodents, where SOX9-positive cells proliferate and regenerate the proximal tubules of injured kidneys. Additionally, SOX9-positive cells demonstrate a capacity to differentiate toward other nephron segments. Here, we characterized the role of SOX9 in normal and injured human kidneys. SOX9 expression was found to colocalize with a proportion of so-called scattered tubular cells in the uninjured kidney, a cell population previously shown to be involved in kidney injury and regeneration. Following injury and in areas adjacent to inflammatory cell infiltrates, SOX9-positive cells were increased in number. With the use of primary tubular epithelial cells (PTECs) obtained from human kidney tissue, SOX9 expression was spontaneously induced in culture and further increased by transforming growth factor-ß1, whereas it was suppressed by interferon-γ. siRNA-mediated knockdown of SOX9 in PTECs followed by analysis of differential gene expression, immunohistochemical expression, and luciferase promoter assays suggested lamin B receptor (LBR), high mobility group AT-hook 2 (HMGA2), and homeodomain interacting protein kinase 3 (HIPK3) as possible target genes of SOX9. Moreover, a kidney explant model was used to demonstrate that only SOX9-positive cells survive the massive injury associated with kidney ischemia and that the surviving SOX9-positive cells spread and repopulate the tubules. Using a wound healing assay, we also showed that SOX9 positively regulated the migratory capacity of PTECs. These findings shed light on the functional and regulatory aspects of SOX9 activation in the human kidney during injury and regeneration.NEW & NOTEWORTHY Recent studies using murine models have shown that SRY box transcription factor 9 (SOX9) is activated during repair of renal tubular cells. In this study, we showed that SOX9-positive cells represent a proportion of scattered tubular cells found in the uninjured human kidney. Furthermore, we suggest that expression of LBR, HMGA2, and HIPK3 is altered by SOX9 in the kidney tubular epithelium, suggesting the involvement of these gene products in kidney injury and regeneration.

SRY-Related Transcription Factors in Head and Neck Squamous Cell Carcinomas: In Silico Based Analysis.

Head and neck squamous cell carcinoma (HNSCC) is the sixth leading cancer and the fifth cause of cancer-related deaths worldwide with a poor 5-year survival. SOX family genes play a role in the processes involved in cancer development such as epithelial-mesenchymal transition (EMT), the maintenance of cancer stem cells (CSCs) and the regulation of drug resistance. We analyzed the expression of SOX2-OT, SOX6, SOX8, SOX21, SOX30 and SRY genes in HNSCC patients using the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets, to assess their biological role and their potential utility as biomarkers. We demonstrated statistically significant differences in expression between normal and primary tumor tissues for SOX6, SOX8, SOX21 and SOX30 genes and pointed to SOX6 as the one that met the independent diagnostic markers criteria. SOX21 or SRY alone, or the panel of six SRY-related genes, could be used to estimate patient survival. SRY-related genes are positively correlated with immunological processes, as well as with keratinization and formation of the cornified envelope, and negatively correlated with DNA repair and response to stress. Moreover, except SRY, all analyzed genes were associated with a different tumor composition and immunological profiles. Based on validation results, the expression of SOX30 is higher in HPV(+) patients and is associated with patients' survival. SRY-related transcription factors have vast importance in HNSCC biology. SOX30 seems to be a potential biomarker of HPV infection and could be used as a prognostic marker, but further research is required to fully understand the role of SOX family genes in HNSCC.

Zinc finger protein 24-dependent transcription factor SOX9 up-regulation protects tubular epithelial cells during acute kidney injury.

Transcriptional profiling studies have identified several protective genes upregulated in tubular epithelial cells during acute kidney injury (AKI). Identifying upstream transcriptional regulators could lead to the development of therapeutic strategies augmenting the repair processes. SOX9 is a transcription factor controlling cell-fate during embryonic development and adult tissue homeostasis in multiple organs including the kidneys. SOX9 expression is low in adult kidneys; however, stress conditions can trigger its transcriptional upregulation in tubular epithelial cells. SOX9 plays a protective role during the early phase of AKI and facilitates repair during the recovery phase. To identify the upstream transcriptional regulators that drive SOX9 upregulation in tubular epithelial cells, we used an unbiased transcription factor screening approach. Preliminary screening and validation studies show that zinc finger protein 24 (ZFP24) governs SOX9 upregulation in tubular epithelial cells. ZFP24, a Cys2-His2 (C2H2) zinc finger protein, is essential for oligodendrocyte maturation and myelination; however, its role in the kidneys or in SOX9 regulation remains unknown. Here, we found that tubular epithelial ZFP24 gene ablation exacerbated ischemia, rhabdomyolysis, and cisplatin-associated AKI. Importantly, ZFP24 gene deletion resulted in suppression of SOX9 upregulation in injured tubular epithelial cells. Chromatin immunoprecipitation and promoter luciferase assays confirmed that ZFP24 bound to a specific site in both murine and human SOX9 promoters. Importantly, CRISPR/Cas9-mediated mutation in the ZFP24 binding site in the SOX9 promoter in vivo led to suppression of SOX9 upregulation during AKI. Thus, our findings identify ZFP24 as a critical stress-responsive transcription factor protecting tubular epithelial cells through SOX9 upregulation.

Comprehensive molecular analysis identifies eight novel variants in XY females with disorders of sex development.

Disorders of sex development (DSD) are a group of clinical conditions with variable presentation and genetic background. Females with or without development of secondary sexual characters and presenting with primary amenorrhea (PA) and a 46,XY karyotype are one of the classified groups in DSD. In this study, we aimed to determine the genetic mutations in 25 females with PA and a 46,XY karyotype to show correlations with their phenotypes. Routine Sanger sequencing with candidate genes like SRY, AR, SRD5A2, and SF1, which are mainly responsible for 46,XY DSD in adolescent females, was performed. In a cohort of 25 patients of PA with 46,XY DSD, where routine Sanger sequencing failed to detect the mutations, next-generation sequencing of a targeted gene panel with 81 genes was used for the molecular diagnosis. The targeted sequencing identified a total of 21 mutations including 8 novel variants in 20 out of 25 patients with DSD. The most frequently identified mutations in our series were in AR (36%), followed by SRD5A2 (20%), SF1 (12%), DHX37 (4%), HSD17B3 (4%), and DMRT2 (4%). We could not find any mutation in the DSD-related genes in five (20%) patients due to complex molecular mechanisms in 46,XY DSD, highlighting the possibility of new DSD genes which are yet to be discovered in these disorders. In conclusion, genetic testing, including cytogenetics and molecular genetics, is important for the diagnosis and management of 46,XY DSD cases.

Spindle pole body component 24 homolog potentiates tumor progression via regulation of SRY-box transcription factor 2 in clear cell renal cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is the most common pathological subtype of human kidney cancer with a high probability of metastasis. To understand the molecular processing essential for ccRCC tumorigenicity, we conducted an integrative in silico analysis of The Cancer Genome Atlas (TCGA) ccRCC dataset and clustered randomly interspersed short palindromic repeats (CRISPR) screening dataset of ccRCC cell lines from Depmap. We identified spindle pole body component 24 homolog (SPC24) as an essential gene for ccRCC cell lines with prognostic significance in the TCGA database. Targeting SPC24 by CRISPR/Cas9-mediated gene knockout attenuated ccRCC proliferation, metastasis, and in vivo tumor growth. Furthermore, we found that SPC24 regulates metastasis genes expression in a SRY-box transcription factor 2 (SOX2)-dependent manner. The anti-proliferative effects of SPC24 knockout were strengthened with SOX2 knockdown. Collectively, our findings suggest SPC24 has a pivotal function in promoting ccRCC progression, providing a new insight for the treatment of ccRCC.