Expression Of Octamer-binding Transcription Factor 4 Research Articles

Trk Inhibition Reduces Tumorsphere Formation and Changes Expression of Stemness Markers in SK-ES-1 Ewing Sarcoma Cells

Introduction: Ewing sarcoma (ES) is a highly aggressive type of childhood cancer characterized by a chromosomal translocation resulting in fusions between the gene encoding EWS RNA Binding Protein 1 (EWSR1) and one gene of the ETS family, most frequently FLI-1, resulting in the EWS-FLI1 aberrant transcription factor. ES tumors can contain a subpopulation of cells showing cancer stem cell (CSC) features, which express stemness markers including CD133, OCT4 (Octamer-binding transcription factor 4), and NANOG, and display capacity to form tumorspheres likely enriched in CSCs. Neurotrophin (NT) receptors of the tropomyosin receptor kinase (Trk) family (TrkA, TrkB, and TrkC) may play a role in stimulating ES progression, but their possible role in CSCs remains unknown. Objective: To verify the effect of Trks inhibition on the formation of tumorspheres as well as the gene expression of stem markers. Method: The cells were dissociated and the formation of spheres was induced with supplemented culture medium and the K252a treatment was performed. After RNA extraction, mRNA expression levels of target genes Prom1 (CD133), OCT4 (POU5F1), SOX2, and Musashi-1 (MSI1) were analyzed by qPCR. Results: The pan-Trk inhibitor K252a (100 or 500 mM) hindered tumorsphere formation in human SK-ES-1 ES cell cultures. K252a also reduced mRNA expression of Prom1 (CD133-coding gene) while enhancing expression of OCT4. No changes in mRNA levels of SOX2 or Musashi-1 were observed. Conclusion: These findings provide the first evidence suggesting that Trk activity can influence stemness in ES cells.

Plantamajoside Reduces Gastric Cancer Cell Migration and Invasion by Inhibiting PI3K/AKT and ERK Pathways

Gastric cancer is a common malignancy with a poor survival rate. Plantamajoside, a phenylethanoid glycoside from Plantago asiatica, has been shown to inhibit the progression of many different types of cancer; however, its effect on gastric cancer remains to be explored. To this end, the effect of plantamajoside on the proliferation, apoptosis, stemness, mobility, and invasion of gastric cancer was evaluated by cell survival assay, flow cytometry, colony formation, sphere formation, transwell, and Western blot assays. Also, the potential molecular mechanism was addressed by Western blot assays for the expression of various signal proteins. Plantamajoside reduced cell viability, enhanced apoptosis, reduced cell mobility, and increased invasion of both AGS and HS746T cells in a dose-dependent manner. Plantamajoside also decreased the diameter of the spheroid and the relative expression of octamer-binding transcription factor-4 and the cluster of differentiation 44 proteins in both AGS and HS746T cells. Furthermore, plantamajoside downregulated the relative protein levels of p-PI3K/ PI3K, p-AKT/AKT, and p-ERK/ERK in both AGS and HS746T cells.

Delivery of dCas9 Activator System Using Magnetic Nanoparticles Technology as a Vector Delivery Method for Human Skin Fibroblast

The overexpression of stem cell-related genes such as octamer-binding transcription factor 4 (OCT4) and (sex determining region Y)-box 2 (SOX2) has been indicated to play several critical roles in stem cell self-renewal; moreover, the elevation of the self-renewal of cancer cells with stem cell-like properties has been suggested. The clustered and regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9) protein fused to transactivation domains can be used to activate gene expression in human cells. CRISPR-mediated activation (CRISPRa) systems represent an effective genome editing tool for highly specific gene activation in which a nuclease-deficient Cas9 (dCas9) is utilized to target a transcriptional activator to the gene’s regulatory element, such as a promoter and enhancer. The main drawback of typical delivery methods for CRISPR/Cas9 components is their low transfection efficiency or toxic effects on cells; thus, we generated superparamagnetic iron oxide nanoparticles (SPIONs) coated with polyethylenimine (PEI) to improve the delivery of CRISPR/Cas9 constructs into human foreskin fibroblast cells. The delivery system with magnetic PEI-coated nanoparticles complex was applied to constitute plasmid DNA lipoplexes. CRISPRa systems were used to overexpress the endogenous OCT4 and SOX2 in fibroblast cells. The quantitative polymerase chain reaction (QPCR) assessment exhibited a three-times higher expression of OCT4 and SOX2 transfected by CRISPRa using MNPs. Moreover, no additional cytotoxicity was observed with the application of magnetic nanoparticles (MNPs) compared to lipofectamine. Our results demonstrate that MNPs enable the effective delivery of the CRISPR/Cas9 construct into human foreskin fibroblasts with low cell toxicity and a consequential overexpression of endogenous OCT4 and SOX2.

HPV16 E6-Activated OCT4 Promotes Cervical Cancer Progression by Suppressing p53 Expression via Co-Repressor NCOR1.

Human papillomaviruses (HPV), mainly HPV16 and HPV18, of high-risk classification are involved in cervical cancer carcinogenesis and progression. Octamer-binding transcription factor 4 (OCT4) is a key transcription factor that is increased in various cancer types. Cervical cancer patients with higher levels of OCT4 had worse survival rates. However, the definite mechanisms underlying its function in the development of cervical cancer still remain to be explicated. Here, our study demonstrated that OCT4 expression was slightly increased in cervical cancer tissues than in precancerous ones. However, OCT4 was significantly upregulated in HPV16-positive tissues, in contrast to the expression profiling for p53. Moreover, knockdown of HPV16 E6 in SiHa cells suppressed the expression of OCT4 with impaired activities of cell proliferation, migration, and invasion, while it recovered the expression of p53. Overexpression of OCT4 and p53 exerted opposite roles on cell proliferation, migration, invasion, and colony formation of cervical cancer cells. More importantly, the enforced expression of OCT4 augmented p53-inhibited cell migration, invasion, and colony formation in human cervical cancer by promoting EMT. Finally, we identified that OCT4 could bind to the p53 promoter region to repress p53 expression by recruiting co-repressor NCOR1 using luciferase, ChIP, and co-IP experiments. We further illustrated that OCT4 not only increased the lung metastasis of cervical cancer but also effectively reversed p53-inhibited lung metastasis. In conclusion, our results suggested that HPV16 E6 activated the expression of OCT4 and subsequently crippled the transcription of p53 via co-repressor NCOR1, which contributed to cervical cancer progression.

Gene Expression of SOX2, OCT4, and Nanog by Small Molecule Compound VC6TFZ on Peripheral Blood Mononuclear Cell

Peripheral blood mononuclear cells are a potential source of cells to be induced into pluripotent stem cells because the collection procedure is easy, minimally invasive, and can be stored in a frozen form. Small molecule compound VC6TFZ consisting of valproic acid (VPA), CHIR990210 (CHIR), 616452, Tranylcypromine, Farsokline, 3-deazaneplanocin (DZnep) and TTNPB has been shown to induce pluripotency in mouse fibroblasts, but this has not been proven in peripheral blood cells. This chemical reprogramming strategy has the potential to be used in producing the desired functional cell types for clinical applications. This study aims to determine whether the small molecule compound VC6TFZ can induce pluripotency of peripheral blood mononuclear cells to become induced pluripotent stem cells. Mononuclear cells were isolated from peripheral venous blood by density gradient centrifugation method. The cells are grouped into 4 groups. Group 1 was the control group, which was not exposed to the small molecule. Groups 2-4 were experimental groups exposed to different doses of the small molecule VC6TFZ. Identification of induced pluripotent stem cells was carried out by identifying colony morphology and pluripotent gene expression of Octamer-binding transcription factor-4 (OCT4), Sex-determining region Y-box 2 (SOX2), and Nanog using Real-Time Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). Colonies with a round shape, large, cobble stone like, and clear boundaries resembling pluripotent stem cell colonies appeared on the 9th day of the induction process. OCT4 and Nanog gene expression were significantly increased in the treatment group compared to the control.

Effects of long-term exposure to sevoflurane on the proliferation, migration, invasion, and cisplatin sensitivity of esophageal cancer.

BackgroundEsophageal cancer has a high incidence and one of the highest mortality rates worldwide. There are few studies on the effects of sevoflurane on postoperative metastasis and recurrence of esophageal cancer. This study aimed to investigate the effect of sevoflurane on the progression of esophageal cancer and the underlying mechanism of the sensitivity to cisplatin.MethodsWe used the esophageal squamous cell carcinoma (ESCC) line EC109 and esophageal adenocarcinoma (EADC) line SKGT-4. Cell proliferation and stemness potential were determined by MTT assay and sphere-forming assays, respectively. The protein expression of (sex determining region Y)-box 2 (SOX2) and octamer-binding transcription factor 4 (OCT4) was determined by western blot. Cell migration and invasion ability were separately determined by scratch assay and transwell assays, respectively. The distribution of cell cycle and apoptosis were detected by flow cytometry, and the levels of lactate dehydrogenase (LDH) were measured by the enzyme-linked immunosorbent assay (ELISA).ResultsIn the SKGT-4 cells, exposure to sevoflurane inhibited proliferation, increased the migration and invasion potential, increased the number of cells in S phase, promoted self-renewal ability, and up-regulated the expression of SOX2 and OCT4 compared with control cells. Compared with the cisplatin treated group, treatment with sevoflurane plus cisplatin reduced the level of LDH and inhibited apoptosis in the SKGT-4 cells. However, sevoflurane did not affect EC109 cells.ConclusionsLong-term exposure to sevoflurane inhibited the proliferation, increased migration and invasion capacity, and decreased the sensitivity to cisplatin in EADC by promoting stemness. However, sevoflurane had no effect on the behavior of ESCC.

Molecular Characterization of Differentiated-Resistance MSC Subclones by Single-Cell Transcriptomes.

Background: The mechanism of tumorigenicity potentially evolved in mesenchymal stem cells (MSCs) remains elusive, resulting in inconsistent clinical application efficacy. We hypothesized that subclones in MSCs contribute to their tumorgenicity, and we approached MSC-subclones at the single-cell level. Methods: MSCs were cultured in an osteogenic differentiation medium and harvested on days 12, 19, and 25 for cell differentiation analysis using Alizarin Red and followed with the single-cell transcriptome. Results: Single-cell RNA-seq analysis reveals a discrete cluster of MSCs during osteogenesis, including differentiation-resistant MSCs (DR-MSCs), differentiated osteoblasts (DO), and precursor osteoblasts (PO). The DR-MSCs population resembled cancer initiation cells and were subjected to further analysis of the yes associated protein 1 (YAP1) network. Verteporfin was also used for YAP1 inhibition in cancer cell lines to confirm the role of YAP1 in MSC--involved tumorigenicity. Clinical data from various cancer types were analyzed to reveal relationships among YAP1, OCT4, and CDH6 in MSC--involved tumorigenicity. The expression of cadherin 6 (CDH6), octamer-binding transcription factor 4 (OCT4), and YAP1 expression was significantly upregulated in DR-MSCs compared to PO and DO. YAP1 inhibition by Verteporfin accelerated the differentiation of MSCs and suppressed the expression of YAP1, CDH6, and OCT4. A survey of 56 clinical cohorts revealed a high degree of co-expression among CDH6, YAP1, and OCT4 in various solid tumors. YAP1 inhibition also down-regulated HeLa cell viability and gradually inhibited YAP1 nuclear localization while reducing the transcription of CDH6 and OCT4. Conclusions: We used single-cell sequencing to analyze undifferentiated MSCs and to discover a carcinogenic pathway in single-cell MSCs of differentiated resistance subclones.

Clinical significance of cytokeratin 19 and OCT4 as survival markers in non-metastatic and metastatic breast cancer patients.

IntroductionCytokeratin 19 (CK19) is highly expressed in epithelial tumours such as breast cancer (BC). Octamer-binding transcription factor 4 (OCT4), a transcription factor of the POU (Pit-Oct-UNC) family, plays a criti-cal role in the self-renewal and maintenance of pluripotency of embryonic stem cells; therefore, it has been used as a promising CSC marker.Material and methodsCK19 was assessed in peripheral blood using flow-cytometric analysis while OCT4 was evaluated in breast tissue samples by immunohistochemistry from 70 patients (non-metastatic BC, meta-static BC, and non-malignant breast tumours).ResultsCK19 and OCT4 were significantly associated with BC patients compared to control (p < 0.001). CK19 was detected in 38 patients with BC (62.2%); meanwhile, OCT4 was positive in 37 BC patients (60.6%). CK19 was positively associated with grade (p = 0.002), HER2 (p = 0.009), metastasis (p = 0.026), molecular subtypes and LN (p < 0.001), and stage (p = 0.001) while OCT4 expression was positively associated with BMI (p < 0.023), aggressive molecular subtype (p < 0.019), ER expression (p = 0.025), presence of LN metastases (p < 0.017), and distant metastasis (p < 0.018). A non-significant relation was found between the expression of CK19 and OCT (p = 0.291). The positive expression of CK19 and OCT4 was significantly and inversely associated with both 3-year OS and 3-year PFS.ConclusionsCK19 and OCT4 are associated with BC, so they can be considered as prognostic and predictive markers for poor OS and PFS in non-metastatic as well as metastatic BC patients.

In Vivo Expression of Reprogramming Factor OCT4 Ameliorates Myelination Deficits and Induces Striatal Neuroprotection in Huntington's Disease.

White matter atrophy has been shown to precede the massive loss of striatal GABAergic neurons in Huntington’s disease (HD). This study investigated the effects of in vivo expression of reprogramming factor octamer-binding transcription factor 4 (OCT4) on neural stem cell (NSC) niche activation in the subventricular zone (SVZ) and induction of cell fate specific to the microenvironment of HD. R6/2 mice randomly received adeno-associated virus 9 (AAV9)-OCT4, AAV9-Null, or phosphate-buffered saline into both lateral ventricles at 4 weeks of age. The AAV9-OCT4 group displayed significantly improved behavioral performance compared to the control groups. Following AAV9-OCT4 treatment, the number of newly generated NSCs and oligodendrocyte progenitor cells (OPCs) significantly increased in the SVZ, and the expression of OPC-related genes and glial cell-derived neurotrophic factor (GDNF) significantly increased. Further, amelioration of myelination deficits in the corpus callosum was observed through electron microscopy and magnetic resonance imaging, and striatal DARPP32+ GABAergic neurons significantly increased in the AAV9-OCT4 group. These results suggest that in situ expression of the reprogramming factor OCT4 in the SVZ induces OPC proliferation, thereby attenuating myelination deficits. Particularly, GDNF released by OPCs seems to induce striatal neuroprotection in HD, which explains the behavioral improvement in R6/2 mice overexpressing OCT4.

Generation of biologically active recombinant human OCT4 protein from E. coli.

The online version contains supplementary material available at 10.1007/s13205-021-02758-z.

Use of miR‑145 and testicular nuclear receptor 4 inhibition to reduce chemoresistance to docetaxel in prostate cancer.

The human testicular nuclear receptor 4 (TR4) is a critical regulatory gene for the progression of prostate cancer (PCa). Although it has been revealed that TR4 causes chemoresistance in PCa via the activation of octamer-binding transcription factor 4 (OCT4), the detailed mechanism remains unexplored. In the present study, it was revealed that inhibition of TR4 by shRNA in PCa enhanced the sensitivity to docetaxel in vitro and in vivo. TR4 induced the downregulation of miR-145 by directly binding it to the promoter of miR-145, which was confirmed by chromatin immunoprecipitation analysis and luciferase assay. The overexpression of miR-145 suppressed both the chemoresistance and the expression of OCT4 mRNA and protein. Additionally, the TR4 shRNA mediated re-sensitization to docetaxel, along with the downregulated expression of OCT4, were reversed by the concurrent inhibition of miR-145. The luciferase assay revealed that the activity of the wild-type OCT4 3′ untranslated region reporter was suppressed. This suppression diminished when the miR-145 response element mutated. These findings suggest an undescribed regulatory pathway in PCa, by which TR4 directly suppressed the expression of miR-145, thereby inhibiting its direct target OCT4, leading to the promotion of chemoresistance in PCa.

Investigation of alterations in PIK3CA and OCT-4 gene expression in breast cancer

Breast cancer (BCa) is one of the most prevalent cancer amongst women and PIK3CA mutations have a crucial role in carcinogenesis. On the other hand, Octamer-Binding Transcription Factor 4 (OCT-4) is common biomarkers of cancer stem cells, which provide to the pathological processes of numerous carcinomas. In this study, we evaluated the association of OCT-4 gene expression levels with the PIK3CA mutation in BCa patients.The mRNA expression level of the OCT-4 gene was detected by qPCR in 44 BCa patients and 30 BCa patients control have positive PIK3CA mutations. Exon 9 and exon 20 of PIK3CA mutations were identified by sequencing. OCT-4 gene expression and PIK3CA mutations were also clinically evaluated in BCa patients.The frequency of PIK3CA mutation in 44 new cases were 32%. PIK3CA mutations were significantly associated with HER2-positive (p = 0.0271) status, Ki-67 status (p = 0.0434) and patient age (p = 0.0149). OCT-4 mRNA expression was significantly higher in the BCa tissue in comparison to normal breast tissue (p = 0.0305). A significant correlation was found between expression of OCT-4 and node status (p = 0.0190). OCT-4 mRNA expression was higher in the PIK3CA mutation tissue than the wild type tissue. However, no association was found between the expression of OCT-4 and the PIK3CA mutation or wild type samples (p = 0.7908).Our results provided that OCT-4 gene and PIK3CA mutations may have a role in development of BCa. OCT-4 mRNA expression level and PIK3CA mutations have a potential important for BCa diagnosis or treatment.

Papillary Thyroid Cancer Tumor Spheres Cultured by Passaging Without Sorting Exhibit Cancer Stemness.

Cancer stem-like cell (CSC) markers and the role of CSCs derived from papillary thyroid carcinoma (PTC) in pathogenesis are unclear. This study aimed to investigate CSC properties using tumor spheres from passaged PTC cells but without sorting CSCs. To identify the properties of CSCs derived from PTC, the expression of SRY-box transcription factor 2(SOX2), octamer-binding transcription factor 4 (OCT4), Nanog homeobox (NANOG), thyroglobulin (TG), thyroid-stimulating hormone receptor (TSHR), E-cadherin, YES-associated protein 1 (YAP1), and signal transducer and activator of transcription 3 (STAT3) was investigated in tumor spheres serially passaged without sorting CSCs. The cultured tumor spheres had cancer stemness; high expression of OCT4, SOX2, NANOG, and YAP1; low expression of E-cadherin; and varied expression of TG, TSHR, and STAT3. PTC tumor spheres transfected with small interfering RNA targeting YAP1 had fewer CSC properties than the non-transfected tumor spheres did. Tumor spheres derived from PTC cells by passaging without sorting CSCs have more stem-like cell properties, and less differentiation potential. Thus, this simple and cost-effective method can be used for the enrichment of PTC stemness for employment in cell-based models, reducing the need for use of animal models.

Role of OCT4 in the Regulation of FSH-Induced Granulosa Cells Growth in Female Mice

As a member of the POU (Pit-Oct-Unc) transcription factor family, OCT4 (Octamer-binding transcription factor 4) is associated with the cellular proliferative. However, the roles of OCT4 in regulating the transition from preantral follicle to early antral follicle are still remains unclear. To evaluate the effect of OCT4 on cellular development in ovary, mice were injected with eCG in vivo or granulosa cells were co-cultured with FSH in vitro. The results showed that eCG up-regulated ovarian OCT4 expression. Meanwhile, OCT4 expression in granulosa cells was also up-regulated by FSH, and knockdown of OCT4 by siRNA significantly decreased FSH-induced cellular viability. Moreover, gonadotropin increased p-GSK3β (Glycogen synthase kinase 3-beta) level, β-catenin expression and its translocation to nuclear in ovarian cells. In addition, the inhibition of GSK3β activity by CT99021 significantly increased the expression of β-catenin and OCT4 in granulosa cells. And knockdown β-catenin by siRNA dramatically abolished FSH-induced OCT4 expression and cellular development. Furthermore, FSH-induced the phosphorylation of GSK3β, expression of β-catenin and OCT4, and translocation of β-catenin were mediated by the PI3K/Akt pathway. Taken together, the present study demonstrates that FSH regulated OCT4 expression via GSK3β/β-catenin pathway, which was mediated by the PI3K/Akt pathway. And these regulations are involved in ovarian cell development.

Putative stemness markers octamer-binding transcription factor 4, sex-determining region Y-box 2, and NANOG in non-small cell lung carcinoma: A clinicopathological association.

The promising improvement in the clinical outcome of lung cancer can be possibly achieved by identification of the molecular events that underlie its pathogenesis. Cancer stem cell (CSC) being one of the subsets of tumor majorly participates in drug resistance and treatment failure because of the moderate cell cycle, lower proliferation, and increased expression of DNA repair and anti-apoptosis genes. Although many putative CSC markers exist, a precise characterization for non-small cell lung cancer is of utmost importance due to increased mortality rate and lack of targeted therapies. Hence, the article focuses on the expression of stemness-associated markers, namely octamer-binding transcription factor 4 (OCT4), NANOG, and sex-determining region Y-box 2 (SOX2) in non-small cell lung cancer (NSCLC) patients. The expression of OCT4, NANOG, and SOX2 were evaluated in 32 histopathologically confirmed NSCLC tissues using real-time polymerase chain reaction. The obtained expression was correlated with clinical and pathological manifestations using the statistical test such as Student's t-test and Pearson correlation in varied statistical software. Results showed a significantly higher expression of OCT4 and NANOG compared to SOX2 in the tumor tissues. When the expression of these markers was correlated with the clinical parameters, higher expression was seen in males, patients with age above 60 years, and in adenocarcinoma subtype. In correlation with the habit, higher expression of OCT4 and SOX2 was observed in habituated patients. Expression of NANOG and OCT4 was higher even in patients with poor differentiation. The expression and prognostic significance of CSC markers obviously vary depending on histological NSCLC subtype. Importantly, our findings suggest that OCT4, SOX2, and NANOG network together may be promising for ongoing targeted therapies in specific NSCLC subgroups.

Effect of low oxygen tension on transcriptional factor OCT4 and SOX2 expression in New Zealand rabbit bone marrow-derived mesenchymal stem cells.

Background and Aim:Octamer-binding transcription factor 4 (OCT4) and sex-determining region Y-box 2 (SOX2) are transcription factors whose functions are essential to maintain the pluripotency of embryonic stem cells. The purpose of this study was to derive stem cells for in vitro culture and to maintain their viability and pluripotency, with the goal to obtain a cell line for transplantation in patients with degenerative diseases or injuries. This research focused on examining the effect of low oxygen tension on the ability of bone marrow-derived mesenchymal stem cells (BM-MSCs) to express OCT4 and SOX2 in vitro.Materials and Methods:BM-MSCs were obtained from femurs of 2000 to 3000 g New Zealand male rabbits. BM-MSCs were divided into three groups to test different culture conditions: A control group under hyperoxia condition (21% O2) and two treatment groups with low oxygen tension (1% and 3% O2). We characterized the BM-MSCs using flow cytometric measurement of cluster differentiation 44 (CD44) and cluster differentiation 90 (CD90) expression. The expression of OCT4 and SOX2 was measured by immunofluorescence staining after 48 h of incubation in chambers with normal or low oxygen tension with controlled internal atmosphere consisting of 95% N2, 5% CO2, and 1% O2 (T1) and 3% O2 (T2). We considered OCT4 and SOX2 as two markers of pluripotency induction. All immunofluorescence data were subjected to a post hoc normality Tukey’s honestly significant difference test; all differences with p<5% were considered significant.Results:BM-MSCs were positive for CD44 and CD90 expression after isolation. Oxygen tension culture conditions of 1% and 3% O2 led to OCT4 and SOX2 expression on culture days 2 and 4 (p<0.05), respectively, as compared to the hyperoxia condition (21% O2).Conclusion:Based on the OCT4 and SOX2 immunofluorescence data, we conclude that the stem cells were pluripotent at low O2 tension (at 1% O2 on day 2 and at 3% O2 on day 4), whereas under 21% O2 the OCT4 and SOX2 were not expressed.

Role of Cancer Stem Cell, Apoptotic Factor, DNA Repair, and Telomerase Toward Radiation Therapy Response in Stage IIIB Cervical Cancer.

ObjectivesCancer stem cells are involved in radioresistant cancers. Transcription factors Sry-related HMG box (SOX2) and octamer binding transcription factor 4 (OCT4) can confer pluripotent cell characteristics and self-renewal ability and are involved in carcinogenesis, metastasis, tumor recurrence, and resistance to therapy. Apoptosis, DNA repair, and telomerase factors also contribute to radioresistance. We sought to identify the role of SOX2 and OCT4 as cancer stem cell markers and their effects on apoptosis (via caspase 3), DNA repair (Chk1) and telomerase (hTERT) in conferring resistance to radiotherapy.MethodsWe conducted a case-control study of 40 patients with stage IIIB cervical squamous cell carcinoma who completed radiation therapy at Cipto Mangunkusumo Hospital, Jakarta, Indonesia. The patients were classified according to their treatment response as having exhibited a complete or incomplete response. Clinical follow-up and Pap smears were performed between six and 12 months after therapy for those with a good initial response to determine the final response to therapy. Immunohistochemistry was used to analyze SOX2, OCT4, caspase-3, Chk1, and hTERT expression in paraffin sections of the initial biopsy.ResultsStrong expression of SOX2 (p = 0.011, p = 0.001) and OCT4 (p < 0.001, p < 0.001) was significantly associated with both an incomplete initial and final therapy response, respectively. Multivariate analysis showed that SOX2 and OCT4 expression levels were the strongest markers of an incomplete response to radiotherapy (odds ratio (OR) = 5.12, p = 0.034, and OR = 17.03, p = 0.004, respectively).ConclusionsStrong expression of SOX2 and OCT4 may be a good indicator of incomplete radiotherapy outcome in patients with stage IIIB cervical cancer.

EXPRESSION OF CANCER STEM CELL MARKER OCTAMER-BINDING TRANSCRIPTION FACTOR 4 IN HIGH-GRADE TRANSITIONAL CELL CARCINOMA

Objectives: The objectives of this study were to provide an outlook of urothelial carcinoma through the immunohistochemical expression patterns of octamer-binding transcription factor 4 (OCT4) in high-grade transitional cell carcinoma (TCC) of the urinary bladder.&#x0D; Methods: A total number of 60 tissue samples were collected for the study. Patients were divided into two groups according to the pathological diagnosis of the bladder tissue, Group A: 30 cases with high-grade TCC of the bladder and Group B: 30 cases with apparently normal bladder tissue. Tissue immunohistochemical analysis was applied to investigate the expression patterns of cancer stem cell (CSC) markers OCT4 in bladder samples.&#x0D; Results: OCT4 was positive in 80% of specimens of Group A and 3.3% in specimens of Group B. The association between OCT4 marker result and certain histopathological features in high-grade group: Positive OCT4 result was found in patients with inflammation and necrosis (90.9%) with a significant association (p=0.013). Regarding muscular invasion, we noticed that 87.5% of patients with muscular invasion showed positive OCT4 marker result with a significant association (p=0.039) between OCT4 marker result and muscular invasion. As well, OCT4 marker was highly sensitive and specific (sensitivity=66.7%, specificity=96.7%, and accuracy=76.7%).&#x0D; Conclusion: There was a significant expression of CSC OCT4 in high-grade TCC, OCT4 can be considered as a key regulator of tumor progression, aggressive behavior, and metastasis.

KLF4 expression in the surgical cut margin is associated with disease relapse of oral squamous cell carcinoma

The presence of cancer stem-like cells (CSCs) in the majority of tumors is one of the factors responsible for disease relapse in oral squamous cell carcinoma (OSCC). In this study, we investigated the role of octamer-binding transcription factor 4 (OCT4) and Kruppel-like factor 4 (KLF4) in OSCC progression and disease relapse. In this study, 102 patients with OSCC were included. The expression of β-catenin and CSC markers (KLF4 and OCT4) in surgical cut margin and tumor were investigated through Western blot analysis, immunohistochemistry, and quantitative polymerase chain reaction analysis. The χ2 test was used to evaluate the association of β-catenin, OCT4, and KLF4 expression with clinicopathologic characteristics. Kaplan-Meier and Cox regression analyses were performed to correlate different clinical factors with the prognoses of patients with OSCC. We observed increased expression of OCT4, KLF4, and β-catenin in the cut margins (CMs) in recurrent OSCC. The χ2 test exhibited recurrence as one of the key factors associated with high expression of these markers. Kaplan-Meier and COX regression analyses demonstrated that increased expression of KLF4 in the CM region of recurrent patients was independently associated with a poor prognosis. Our findings indicated that expression of KLF4 can be used for monitoring disease progression and may serve as prognostic marker to predict recurrence.

Protein expression of the transcription factors DMRT1, TCLF5, and OCT4 in selected germ cell neoplasms of the testis

In the present study, we investigated protein expression of the transcription factors mammalian doublesex and mab-3 related transcription factor 1 (DMRT1), basic helix-loop-helix transcription factor-like 5 (TCLF5), and octamer-binding transcription factor 4 (OCT4) in normal human spermatogenesis, testicular mixed germ cell-sex cord stromal tumor (MGC-SCST), spermatocytic tumor, and seminoma. In normal human spermatogenesis, DMRT1 is expressed in the nuclei of spermatogonia but not in those of more mature germ cells. By way of contrast, TCLF5 is expressed in the nuclei of some clusters of primary spermatocytes that have entered meiosis 1, in secondary spermatocytes, and in round (early) spermatids in the seminiferous tubules of adults during the reproductive years. OCT4 is expressed in primordial germ cells but not in the seminiferous tubules of the normal adult testis during the reproductive years. DMRT1 is expressed in the germ cells of both testicular MGC-SCST and spermatocytic tumor, whereas TCLF5 is not expressed in either neoplasm. These low-grade neoplasms, however, differ histologically in that all the germ cell nuclei of testicular MGC-SCST resemble spermatogonia, whereas in spermatocytic tumor, the nuclei of the medium-sized and large cells resemble those of primary spermatocytes. Both neoplasms lack expression of OCT4. By way of contrast, in seminoma, a fully malignant testicular germ cell tumor, the germ cell nuclei express OCT4 but do not express either DMRT1 or TCLF5.