Prognostic and clinicopathological significance of cyclin D1 expression in oral squamous cell carcinoma: A systematic review and meta-analysis

F. Nucleatum enhances oral squamous cell carcinoma proliferation via E-cadherin/β-Catenin pathway

BACKGROUND

Fusobacterium nucleatum (F. nucleatum) is a microbial risk factor whose presence increases the risk of oral squamous cell carcinoma (OSCC) progression. However, whether it can promote the proliferation of OSCC cells remains unknown.

METHODS

In this study, we investigated F. nucleatum effect on OSCC cell proliferation using in vitro and in vivo experiments.

RESULTS

Our results showed that F. nucleatum promoted OSCC cell proliferation, doubling the cell count after 72 h (CCK-8 assay). Cell cycle analysis revealed G2/M phase arrest. F. nucleatum interaction with CDH1 triggered phosphorylation, upregulating downstream protein β-catenin and activating cyclinD1 and Myc. Notably, F. nucleatum did not affect noncancerous cells, unrelated to CDH1 expression levels in CAL27 cells. Overexpression of phosphorylated CDH1 in 293T cells did not upregulate β-catenin and cycle-related genes. In vivo BALB/c nude experiments showed increased tumor volume and Ki-67 proliferation index after F. nucleatum intervention.

CONCLUSION

Our study suggests that F. nucleatum promotes OSCC cell proliferation through the CDH1/β-catenin pathway, advancing our understanding of its role in OSCC progression and highlighting its potential as a therapeutic target.

Oral squamous cell carcinomas: state of the field and emerging directions

Oral squamous cell carcinoma (OSCC) develops on the mucosal epithelium of the oral cavity. It accounts for approximately 90% of oral malignancies and impairs appearance, pronunciation, swallowing, and flavor perception. In 2020, 377,713 OSCC cases were reported globally. According to the Global Cancer Observatory (GCO), the incidence of OSCC will rise by approximately 40% by 2040, accompanied by a growth in mortality. Persistent exposure to various risk factors, including tobacco, alcohol, betel quid (BQ), and human papillomavirus (HPV), will lead to the development of oral potentially malignant disorders (OPMDs), which are oral mucosal lesions with an increased risk of developing into OSCC. Complex and multifactorial, the oncogenesis process involves genetic alteration, epigenetic modification, and a dysregulated tumor microenvironment. Although various therapeutic interventions, such as chemotherapy, radiation, immunotherapy, and nanomedicine, have been proposed to prevent or treat OSCC and OPMDs, understanding the mechanism of malignancies will facilitate the identification of therapeutic and prognostic factors, thereby improving the efficacy of treatment for OSCC patients. This review summarizes the mechanisms involved in OSCC. Moreover, the current therapeutic interventions and prognostic methods for OSCC and OPMDs are discussed to facilitate comprehension and provide several prospective outlooks for the fields.

Prognostic and Clinicopathological Significance of Epidermal Growth Factor Receptor (EGFR) Expression in Oral Squamous Cell Carcinoma: Systematic Review and Meta-Analysis

The aim of this systematic review and meta-analysis was to evaluate the current evidence in relation to the clinicopathological and prognostic significance of epidermal growth factor receptor (EGFR) overexpression in patients with oral squamous cell carcinoma (OSCC). We searched MEDLINE/PubMed, Embase, Web of Science, and Scopus for studies published before November 2022. We evaluated the quality of primary-level studies using the QUIPS tool, conducted meta-analyses, examined inter-study heterogeneity via subgroup analyses and meta-regressions, and performed small-study effects analyses. Fifty primary-level studies (4631 patients) met the inclusion criteria. EGFR overexpression was significantly associated with poor overall survival (hazard ratio [HR] = 1.38, 95% confidence intervals [CI] = 1.06-1.79, p = 0.02), N+ status (odds ratio [OR] = 1.37, 95%CI = 1.01-1.86, p = 0.04), and moderately-poorly differentiated OSCC (OR = 1.43, 95% CI = 1.05-1.94, p = 0.02). In addition, better results were obtained by the application of a cutoff point ≥10% tumor cells with EGFR overexpression (p < 0.001). In conclusion, our systematic review and meta-analysis supports that the immunohistochemical assessment of EGFR overexpression may be useful as a prognostic biomarker for OSCC.

Evaluation of Cyclin D1 and Human Epidermal Growth Factor Receptor 2 Neu Protein Expression in Head and Neck Squamous Cell Carcinoma

Background Head and neck cancers are highly aggressive, frequently occurring cancers that are prevalent worldwide. The mainstay of their treatment is surgery, followed by adjuvant therapy. Various studies have documented the usefulness of molecular markers in carcinogenesis and have proven helpful in the diagnosis and treatment of head and neck cancers. Cyclin D1 is a proto‑oncogene, overexpression of which leads to the accelerated entry of cells in the S phase of the cell cycle, causing uncontrolled proliferation of the cells. The dysregulation of human epidermal growth factor receptor 2 (HER2) neu is also related to multiple features of malignancy, including loss of cell cycle control, induction of angiogenesis, and resistance to apoptotic stimuli. This study seeks to identify a subset of patients with a bad prognosis who may require aggressive treatment strategies. Aim This study aims to determine the proportion of the expression of cyclin D1 and HER2 neu in head and neck squamous cell carcinoma (HNSCC) and analyze the association between the expression of cyclin D1 and HER2 neu using histological grading, tumor, node, and metastasis (TNM) staging, and nodal status of the tumor. Furthermore, this study also aims to document clinical outcomes, such as locoregional control, depth of invasion (DOI), and regional metastasis regarding the expression of cyclin D1 and HER2 neu in HNSCC. Setting and design This study is a laboratory-based observational study. Materials and methods Seventy histologically proven cases of HNSCC were studied for various histopathological parameters, and further immunohistochemistry (IHC) was performed for cyclin D1 and HER2 neu. The expression and intensity of cyclin D1 were multiplied, and the total score was derived. The College of American Pathologists/American Society of Clinical Oncology (CAP/ASCO) guidelines for HER2 neu testing in breast cancer were used for scoring. Result Out of 70 cases, 52 (75%) demonstrated strong and moderate positivity for cyclin D1, and the p-values were 0.017, 0.001, and 0.032 for depth of invasion, TNM stage, and lymph node metastases, respectively, for cyclin D1, which was considered statistically significant. For HER2 neu, five out of 70 cases were positive, and the p-value was significant for depth of invasion (0.008). Conclusion The expression of the above marker cyclin D1 increases with stage, DOI, and positive lymph node status. Hence, cyclin D1 immunoexpression can be helpful in the early assessment of HNSCC behavior and can serve as an independent prognostic marker. Furthermore, it was observed that HER2 neu was significant with an increase in depth of invasion of tumor, which, in the American Joint Committee on Cancer (AJCC) eighth edition, is considered an important factor for determining the stage of the tumor. Further research is needed to examine whether HER2 neu can act as a prognostic factor for HNSCC and if it can be targeted for treatment options.

Clinicopathological and prognostic value of chemokine receptor CCR7 expression in head and neck squamous cell carcinoma: a systematic review and meta-analysis

OBJECTIVES

This study aimed to identify the clinicopathological characteristics and prognostic value of CC chemokine receptor 7 (CCR7) expression in patients with head and neck squamous cell carcinoma (HNSSC).

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed in this meta-analysis. Up to the 2^nd of July 2022 a search was conducted using five databases: PubMed, Embase, Scopus, ProQuest, and Web of Science. The methodological standards for the epidemiological research scale were used to assess the quality of the included articles, and Stata software was used to synthesise the meta-analysis.

RESULTS

We considered 13 of the 615 studies which included 1005 HNSCC patients. High expression of CCR7 increased the pooled odds ratio (OR) of advanced stage, tumour size, metastasis and recurrence by 2.82 [95% confidence interval (CI) 1.84 to 4.33], 2.48 (95% CI 1.68, to 3.67), 3.57, 95% CI 2.25 to 5.05) and 3.93 (95% CI 2.03 to 7.64), respectively. High CCR7 reduced overall patient survival [hazard ratio 2.62 (95% CI 1.59 to 4.32)].

CONCLUSION

This study showed that high expression of CCR7 in HNSCC tumours was significantly associated with worse clinicopathological and survival outcomes, suggesting that CCR7 and its pathway could be potential therapeutic strategies for HNSCC.

Hallmarks of Cancer Expression in Oral Lichen Planus: A Scoping Review of Systematic Reviews and Meta-Analyses

Oral lichen planus (OLP) is a common chronic inflammatory disease of unknown etiology and likely autoimmune nature that is currently considered an oral potentially malignant disorder, implying that patients suffering from this process are at risk of developing oral cancer in their lifetime. The molecular alterations that develop in OLP and that make the affected oral epithelium predisposed to malignancy are unknown, although, as in other autoimmune diseases (ulcerative colitis, primary biliary cirrhosis, etc.), they may be linked to oncogenesis-promoting effects mediated by the inflammatory infiltrate. So far there is no in-depth knowledge on how these hallmarks of cancer are established in the cells of the oral epithelium affected by OLP. In this scoping review of systematic reviews and meta-analyses the state of evidence based knowledge in this field is presented, to point out gaps of evidence and to indicate future lines of research. MEDLINE, Embase, Cochrane Library and Dare were searched for secondary-level studies published before October 2022. The results identified 20 systematic reviews and meta-analyses critically appraising the hallmarks tumor-promoting inflammation (n = 17, 85%), sustaining proliferative signaling (n = 2, 10%), and evading growth suppressors (n = 1, 5%). No evidence was found for the other hallmarks of cancer in OLP. In conclusion, OLP malignization hypothetically derives from the aggressions of the inflammatory infiltrate and a particular type of epithelial response based on increased epithelial proliferation, evasion of growth-suppressive signals and lack of apoptosis. Future evidence-based research is required to support this hypothesis.

Hallmarks of Cancer Applied to Oral and Oropharyngeal Carcinogenesis: A Scoping Review of the Evidence Gaps Found in Published Systematic Reviews

Simple Summary

This scoping review of systematic reviews aims to accurately assess the degree of existing scientific evidence on the cancer hallmarks proposed in 2011 by Hanahan and Weinberg, in the form of systematic reviews and meta-analyses, applied to oral potentially malignant disorders, oral cavity and oropharyngeal squamous cell carcinomas, in order to point out gaps in evidence and lines of research that should be implemented in the future to improve the malignant transformation prediction, diagnosis and/or prognosis of these diseases.

Abstract

In 2000 and 2011, Hanahan and Weinberg published two papers in which they defined the characteristics that cells must fulfil in order to be considered neoplastic cells in all types of tumours that affect humans, which the authors called “hallmarks of cancer”. These papers have represented a milestone in our understanding of the biology of many types of cancers and have made it possible to reach high levels of scientific evidence in relation to the prognostic impact that these hallmarks have on different tumour types. However, to date, there is no study that globally analyses evidence-based knowledge on the importance of these hallmarks in oral and oropharyngeal squamous cell carcinomas. For this reason, we set out to conduct this scoping review of systematic reviews with the aim of detecting evidence gaps in relation to the relevance of the cancer hallmarks proposed by Hanahan and Weinberg in oral and oropharyngeal cancer, and oral potentially malignant disorders, and to point out future lines of research in this field.

Prognostic Significance of CircRNAs Expression in Oral Squamous Cell Carcinoma

OBJECTIVE

This systematic review was aimed to comprehensively evaluate the clinicopathological and prognostic value of dysregulated expression of circRNAs in OSCC.

MATERIALS AND METHODS

The research was carried out by searching mainstream electronic databases including PubMed, Embase, Web of Science, Scopus, LILACS and Cochrane Library to collect relevant studies on prognostic role of circRNAs in OSCC. Pooled hazard ratios (HRs) and odds ratios(ORs) with 95% confidence intervals(CIs) were calculated to assess the association between circRNAs expression, overall survival(OS), disease/recurrence/progression survival(DFS/RFS/PFS) and clinical parameters.

RESULTS

This research included 1813 patients from 26 selected articles. The pooled HR values(95% CIs) in OS were 2.38(1.92-2.93) for oncogenic circRNAs and 0.43(0.28-0.66) for tumor-suppressor circRNAs respectively, in DFS/RFS/PFS were 2.34(1.73-3.17). The meta-analysis on clinicopathology features showed higher level of oncogenic circRNAs is related to advanced TNM stage and tumor stage, worse histological differentiation, lymph node and distant metastasis, while enforced expression of tumor-suppressor circRNAs is related to inferior TNM stage tumor stage and lymphatic metastasis.

CONCLUSION

Our meta-analysis implies that circRNAs may be candidate biomarkers for the prognosis and clinicopathology of OSCC.

The Relationship between MACC1/c-Met/Cyclin D1 Axis Expression and Prognosis in ESCC

Background

Esophageal cancer is one of the most common malignant tumors of the digestive system, with high incidence and mortality.

Methods

Immunohistochemical method was used to detect the expression of MACC1, c-Met, and cyclin D1 in ESCC and its adjacent tissues. Statistical analysis was done by SPSS 23.0.

Results

The high expression of MACC1 and cyclin D1 was significantly correlated with tumor size. High c-Met expression was associated with patient ethnicity. MACC1 expression was positively correlated with both c-Met and cyclin D1. c-Met expression was also positively correlated with cyclin D1. Patients with high expression of MACC1 and c-Met had worse OS; patients with high c-Met expression also had worse PFS.

Conclusion

MACC1, c-Met, and cyclin D1 proteins are closely related to the occurrence and development of esophageal squamous cell carcinoma. MACC1 may affect the prognosis of ESCC by regulating the expression of the c-Met/cyclin D1 axis.

18F-FDG PET cannot predict expression of clinically relevant histopathological biomarkers in head and neck squamous cell carcinoma: a meta-analysis

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is a common cancer. Positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) is a widely used imaging modality in HNSCC.

PURPOSE

To provide evident data about associations between 18F-FDG PET and histopathology in HNSCC.

MATERIAL AND METHODS

The MEDLINE database was screened for associations between maximum standard uptake values (SUV_max) derived from 18F-FDG PET and histopathological features in HNSCC up to May 2020. Only papers containing correlation coefficients between SUV_max and histopathology were acquired. Overall, 23 publications were collected.

RESULTS

The following correlations were calculated: KI 67: 12 studies (345 patients), pooled correlation coefficient (PCC): 0.23 (95% confidence interval [CI] 0.06-0.40); hypoxia-inducible factor-1α: eight studies (240 patients), PCC: 0.24 (95% CI 0.06-0.42); microvessel density: three studies (64 patients), PCC: 0.33 (95% CI 0.02-0.65); vascular endothelial growth factor: two studies (59 cases), PCC: 0.27 (95% CI 0.02-0.51); tumor suppressor protein p53: four studies (159 patients), PCC: 0.05 (95% CI -0.41 to 0.51); epidermal growth factor receptor: two studies (124 patients), PCC: 0.21 (95% CI 0.05-0.37); tumor cell count: three studies (67 patients), PCC: 0.18 (95% CI -0.06 to 0.42); tumor cell apoptosis: two studies (40 patients), PCC: 0.07 (95% CI = -0.85 to 0.99); B-cell lymphoma-2 protein: two studies (118 patients); PCC: 0.04 (95% CI -0.65 to 0.74); glucose-transporter 1: 10 studies (317 patients), PCC: 0.20 (95% CI 0.10-0.30).

CONCLUSION

SUV_max derived from 18F-FDG PET cannot reflect relevant histopathological features in HNSCC.

The Prognostic Role of Cyclin D1 in Multiple Myeloma: A Systematic Review and Meta-Analysis

Purpose: Cyclin D1 has been identified as a proto-oncogene associated with the uncontrolled proliferation of tumor cells. This systematic review and meta-analysis aims to estimate the prognostic significance of cyclin D1 in multiple myeloma (MM) patients. Method: We searched for qualified data in PubMed, Embase, and Web of Science up to February 2020. Data quality was assessed by the Newcastle-Ottawa scale (NOS). Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were used to evaluate the relationship between cyclin D1 expression and overall survival (OS), progression-free survival (PFS)/event-free survival (EFS) in patients with MM. Result: A total of 13 studies involving 961 patients were included. Overall, pooled analysis revealed significant heterogeneity between cyclin D1 expression and the prognosis of MM (OS, HR = 1.08, 95% CI: 0.71-1.64, I2 = 67.9%; PFS/EFS, HR = 0.97, 95% CI: 0.49-1.93, I2 = 85.8%). Subgroup analysis revealed that the prolongation of OS was relevant to increased expression of cyclin D1 in MM patients in the relapsed and refractory group (OS, HR = 0.46, 95% CI: 0.24-0.90). Another subgroup assessment of OS established that MM patients with CCND1 overexpression in the bortezomib group had longer survival time (HR = 0.30, 95% CI: 0.11-0.82), whereas, those overexpressing CCND1 in the conventional chemotherapy group had poor prognosis (HR = 2.19, 95% CI: 1.18-4.08). We also found that increased cyclin D1 expression correlated favorably with PFS in the autologous stem cell transplantation (ASCT) (HR = 0.45, 95% CI: 0.28-0.73) or reverse transcription-polymerase chain reaction (RT-PCR) group (HR = 0.41, 95% CI: 0.26-0.64). Conclusion: The result of this meta-analysis suggested that CCND1 overexpression might be a predictive biomarker for MM patients when treated with bortezomib, receiving ASCT, or in relapsed and refractory period.

Prognostic and Clinicopathological Significance of the Aberrant Expression of β-Catenin in Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

Simple Summary

β-catenin is a multifunctional protein whose physiological functions are mainly related to the maintenance of cell-cell adhesion by forming complexes with the adhesion molecule E-cadherin, both responsible for the preservation of squamous epithelia homeostasis. The loss of β-catenin expression in the cell membrane, the failure of cytoplasmic degradation mechanisms—essentially related to the activation of Wnt canonical oncogenic pathway—and/or its translocation to the nucleus—developing actions as a transcription factor of oncogenes—are aberrant mechanisms with oncogenic implications in oral carcinogenesis. In this systematic review and meta-analysis on 41 studies and 2746 oral squamous cell carcinoma (OSCC) patients we demonstrate that the aberrant expression of β-catenin—mainly the immunohistochemical analysis of its loss in the cell membrane—behaves as a prognostic biomarker, significantly associated with poor survival, essentially linked to the increased risk for the development of lymph node metastases, higher tumour size and clinical stage in these patients.

Abstract

This systematic review and meta-analysis aims to evaluate the prognostic and clinicopathological significance of the aberrant expression of β-catenin (assessed through the immunohistochemical loss of membrane expression, cytoplasmic and nuclear expression) in oral squamous cell carcinoma (OSCC). We searched for primary-level studies published before October-2021 through PubMed, Embase, Web of Science, Scopus, and Google Scholar, with no limitation in regard to their publication date or language. We evaluated the methodological quality and risk of bias of the studies included using the QUIPS tool, carried out meta-analyses, explored heterogeneity and their sources across subgroups and meta-regression, and conducted sensitivity and small-study effects analyses. Forty-one studies (2746 patients) met inclusion criteria. The aberrant immunohistochemical expression of β-catenin was statistically associated with poor overall survival (HR = 1.77, 95% CI = 1.20–2.60, p = 0.004), disease-free survival (HR = 2.44, 95% CI = 1.10–5.50, p = 0.03), N+ status (OR = 2.39, 95% CI = 1.68–3.40, p < 0.001), higher clinical stage (OR = 2.40, 95% CI = 1.58–3.63, p < 0.001), higher tumour size (OR = 1.76, 95% CI = 1.23–2.53, p = 0.004), and moderately-poorly differentiated OSCC (OR = 1.57, 95% CI = 1.09–2.25, p = 0.02). The loss of β-catenin in the cell membrane showed the largest effect size in most of meta-analyses (singularly for poor overall survival [HR = 2.37, 95% CI = 1.55–3.62, p < 0.001], N+ status [OR = 3.44, 95% CI = 2.40–4.93, p < 0.001] and higher clinical stage [OR = 2.51, 95% CI = 1.17–5.35, p = 0.02]). In conclusion, our findings indicate that immunohistochemical assessment of the aberrant expression of β-catenin could be incorporated as an additional and complementary routine prognostic biomarker for the assessment of patients with OSCC.

Circular RNA Mitochondrial Translation Optimization 1 homologue (CircMTO1) induced by Zinc Finger Protein 460 (ZNF460) promotes oral squamous cell carcinoma progression through the microRNA miR-320a / Alpha Thalassemia/Mental Retardation, X-linked (ATRX) axis

Oral squamous cell carcinoma (OSCC) is one of the most common cancer types of head and neck cancer, accounting for 95% of all cases. However, the mechanisms underlying the pathogenesis of OSCC remain unclear. Circular RNA (CircRNA) has been extensively studied in the past decades and is a promising direction for the development of OSCC therapeutic targets. In this study, we aimed to investigate the role of circMTO1 in OSCC progression. First, we validated the characterization and expression of circMTO1 in OSCC. It was found that circMTO1 was upregulated in OSCC tumor tissues and cells. Subsequently, we conducted biological experiments. It was found that circMTO1 knockdown inhibited OSCC cell proliferation, migration, and invasion. Furthermore, we conducted a series of experiments to elucidate the underlying mechanisms. A novel circMTO1/miR-320a/ATRX axis was identified. Our results suggest that circMTO1 modulates ATRX expression to accelerate OSCC progression by sponging miR-320a. Moreover, we found that circMTO1 expression in OSCC was transcriptionally regulated by Zinc Finger Protein 460 (ZNF460). Our study showed a novel ZNF460/circMTO1/miR-320a/ATRX signaling in OSCC development.

Human papillomavirus co-infection and survival in oral and oropharyngeal squamous cell carcinoma: A study in 235 Brazilian patients

OBJECTIVES

While unknown for oropharyngeal squamous cell carcinoma (OPSCC) and oral squamous cell carcinoma (OSCC), some studies assessing cervical carcinoma have shown that human papillomavirus (HPV) co-infection can be associated with its prognosis.

METHODS

Through in situ hybridization (HPV and Epstein-Barr virus [EBV] probes) and immunohistochemistry (p16^INK4a, cyclin D1, p53, and Ki-67 antibodies), 126 OPSCC and 109 OSCC samples were assessed.

RESULTS

All patients were EBV-negative. OPSCC (25%) showed a significant association with HPV compared to OSCC (11%). Almost all HPV-associated cases were p16^INK4a-positive. Regarding OPSCC and OSCC, 23 and 7 cases were positive for high-risk HPV (HRHPV) only, 6 and 3 cases for low-risk HPV (LRHPV) only, and 3 and 2 cases for HRHPV/LRHPV, respectively. HPV-associated carcinomas showed a significantly higher proliferative index than HPV-unassociated carcinomas. Both carcinomas showed a similar overall survival rate, which was not affected by the HPV status. However, when comparing HPV-associated subgroups, patients with HRHPV/LRHPV-associated carcinomas showed worse survival.

CONCLUSION

LRHPV-associated and HRHPV/LRHPV-associated cases can also be detected when assessing OSCC and OPSCC. Further studies, especially in populations with a high prevalence of HPV-associated OPSCC, are necessary to understand the clinicopathological behavior of these neoplasm subgroups.

Prognostic and Clinicopathological Significance of CCND1/Cyclin D1 Upregulation in Melanomas: A Systematic Review and Comprehensive Meta-Analysis

Our objective was to evaluate the prognostic and clinicopathological significance of cyclin D1 (CD1) overexpression/CCND1 amplification in melanomas. We searched studies published before September 2019 (PubMed, Embase, Web of Science, Scopus). We evaluated the quality of the studies included (QUIPS tool). The impact of CD1 overexpression/CCND1 amplification on overall survival and relevant clinicopathological characteristic were meta-analyzed. We performed heterogeneity, sensitivity, small-study effects, and subgroup analyses. Forty-one studies and 3451 patients met inclusion criteria. Qualitative evaluation demonstrated that not all studies were performed with the same rigor, finding the greatest risk of bias in the study confounding domain. Quantitative evaluation showed that immunohistochemical CD1 overexpression had a statistical association with Breslow thickness (p = 0.007; OR = 2.09,95% CI = 1.23-3.57), significantly higher frequency of CCND1/cyclin D1 abnormalities has been observed in the primary tumor compared to distant metastases (p = 0.004), revealed also by immunohistochemical overexpression of the protein (p < 0.001; OR = 0.53,95% CI = 0.40-0.71), while the CCND1 gene amplification does not show association (p = 0.43); while gene amplification, on the contrary, appeared more frequently in distant metastases (p = 0.04; OR = 1.70,95% CI = 1.01-2.85) and not in the primary tumor. In conclusion, CCND1/cyclin D1 upregulation is a common molecular oncogenic alteration in melanomas that probably favors the growth and expansion of the primary tumor. This upregulation is mainly consequence to the overexpression of the cyclin D1 protein, and not to gene amplification.

Alteration of Pituitary Tumor Transforming Gene 1 by MicroRNA-186 and 655 Regulates Invasion Ability of Human Oral Squamous Cell Carcinoma

Background: Pituitary tumor-transforming gene 1 (PTTG1) was recently shown to be involved in the progression as well as the metastasis of cancers. However, their expression and function in the invasion of oral squamous cell carcinoma (SCC) remain unclear. Methods: The expressions of PTTG1 and PTTG1-targeted miRNA in oral SCC cell lines and their invasion capability depended on PTTG1 expression were analyzed by quantitative RT-PCR, Western blots, the transwell insert system and Zymography. Results: Invasion abilities were decreased in oral SCC cells treated with siRNA-PTTG1. When PTTG1 were downregulated in oral SCC cells treated with microRNA-186 and -655 inhibited their invasion abilities via MMP-9 activity. Conclusions: These results indicate that alteration of expression of PTTG1 in oral SCC cells by newly identified microRNA-186 and -655 can regulate invasion activity. Therefore, these data offer new insights into further understanding PTTG1 function in oral SCC and should provide new strategies for diagnostic markers for oral SCC.

Molecular phenotypes of circulating tumor cells and efficacy of nivolumab treatment in patients with head and neck squamous cell carcinoma

The emergence of immune checkpoint inhibitors (ICIs) has revolutionized the treatment of recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC). Biomarkers of the therapeutic efficacy of ICIs have been extensively investigated. In this study, we aimed to analyze whether molecular phenotypes of circulating tumor cells (CTCs) are associated with treatment responses and clinical outcomes in patients with R/M HNSCC treated with nivolumab. Peripheral blood samples were collected before treatment initiation and after four infusions of nivolumab. CTCs isolated by depletion of CD45-positive cells were analyzed to determine the expression of EPCAM, MET, KRT19, and EGFR using real-time quantitative polymerase chain reaction. CTC-positive samples were analyzed to determine the expression of PIK3CA, CCND1, SNAI1, VIM, ZEB2, CD44, NANOG, ALDH1A1, CD47, CD274, and PDCD1LG2. Of 30 patients treated with nivolumab, 28 (93.3%) were positive for CTCs. In 20 CTC-positive patients, molecular alterations in CTCs before and after nivolumab treatment were investigated. Patients with MET-positive CTCs had significantly shorter overall survival than those with MET-negative CTCs (p = 0.027). The expression level of CCND1 in CTCs of disease-controlled patients was significantly higher than that of disease-progressed patients (p = 0.034). In disease-controlled patients, the expression level of CCND1 in CTCs significantly decreased after nivolumab treatment (p = 0.043). The NANOG expression in CTCs was significantly increased in disease-controlled patients after nivolumab treatment (p = 0.036). Our findings suggest that the molecular profiling of CTCs is a promising tool to predict the treatment efficacy of nivolumab.

MAGE-A3 is a prognostic biomarker for poor clinical outcome in cutaneous squamous cell carcinoma with perineural invasion via modulation of cell proliferation

Perineural invasion is a pathologic process of neoplastic dissemination along and invading into the nerves. Perineural invasion is associated with aggressive disease and a greater likelihood of poor outcomes. In this study, 3 of 9 patients with cutaneous squamous cell carcinoma and perineural invasion exhibited poor clinical outcomes. Tumors from these patients expressed high levels of MAGE-A3, a cancer testis antigen that may contribute to key processes of tumor development. In addition to perineural invasion, the tumors exhibited poor differentiation and deep invasion and were subsequently classified as Brigham and Women's Hospital tumor stage 3. Cyclin E, A and B mRNA levels were increased in these tumors compared with normal skin tissues (102.93±15.03 vs. 27.15±4.59, 36.83±19.41 vs. 11.59±5.83, 343.77±86.49 vs. 95.65±29.25, respectively; p<0.05). A431 cutaneous squamous cell carcinoma cells pretreated with MAGE-A3 antibody exhibited a decreased percentage S-phase cells (14.13±2.8% vs. 33.97±1.1%; p<0.05) and reduced closure in scratch assays (43.88±5.49% vs. 61.17±3.97%; p = 0.0058). In a syngeneic animal model of squamous cell carcinoma, immunoblots revealed overexpression of MAGE-A3 and cyclin E, A, and B protein in tumors at 6 weeks. However, knockout of MAGE-A3 expression caused a reduction in tumor growth (mean tumor volume 155.3 mm3 vs. 3.2 mm3) compared with parental cells. These results suggest that MAGE-A3 is a key mediator in cancer progression. Moreover, elevated collagen XI and matrix metalloproteases 3, 10, 11, and 13 mRNA levels were observed in poorly differentiated cutaneous squamous cell carcinoma with perineural invasion compared with normal skin tissue (1132.56±882.7 vs. 107.62±183.62, 1118.15±1109.49 vs. 9.5±5, 2603.87±2385.26 vs. 5.29±3, 957.95±627.14 vs. 400.42±967.66, 1149.13±832.18 vs. 19.41±35.62, respectively; p<0.05). In summary, this study highlights the potential prognostic value of MAGE-A3 in clinical outcomes of cutaneous squamous cell carcinoma patients.

Effect of Photodynamic Therapy on Cyclin D1 and P53 mRNA Levels in Head and Neck Squamous Cell Carcinoma Cell Line

Background: Photodynamic Therapy (PDT) is considered as one of the alternative treatments for Head and Neck Squamous Cell Carcinoma (HNSCC). P53 mRNA is a tumor suppressor gene whose mutation increases the likelihood of uncontrolled cancer-like divisions. The mutation of CCND1 oncogenic increases the production of cyclin D1 as a tumorigenic protein. Objectives: This study aimed to determine the effect of PDT using toluidine blue as a photosensitizer on the CCND1 and P53 mRNA levels in the HNSCC cell line. Methods: A human HNSCC cell line from NCBI.C196 designation HN5 was used. Cells were divided into four groups: Group I (HNSCC cell line under the influence of toluidine blue and laser irradiation), group II (HNSCC cell line under the influence of toluidine blue), group III (HNSCC cell line under laser irradiation), group IV (control group, HNSCC cell line). A 660 nm THOR laser using toluidine blue as a photosensitizer was applied. The RNA extraction was performed in three steps, including cell degradation, purification, and precipitation by alcohol. The cDNA was prepared using Takara Kit. The Amplicon kit and Real-Time PCR analysis were used for the assessment of mRNA relative levels. Results: The P53 mRNA relative levels were 1.50 ± 0.33 in group I (P = 0.65), 1.49 ± 0.23 (P =0.5) in group II, and 1.40 ± 1.05 (P = 0.63) in group III. Compared to the control group, the mean increases in CCND1 mRNA were 18.01 ± 3.37 (p=0.04) in group I, 17.69 ± 3.3 (P = 0.03) in group II, and 9.01 ± 6.17 (P = 0.20) in group III. Conclusions: The comparison of the fold change index for P53 and CCND1 mRNA by the one-way ANOVA test showed that despite the increased expression of P53 and CCND1 mRNA in treatment groups compared to the control group, there was no statistically significant difference between the increases in P53 mRNA (P = 0.99) and CCND1 mRNA (P = 0.22) index between the groups. The results of this study could be a starting point for a better understanding of the mechanism of genes in PDT of the HNSCC cell line.

Age and risk of recurrence in oral tongue squamous cell carcinoma: Systematic review

The incidence of oral tongue squamous cell carcinoma has been increasing in young patients (≤45 years) without a clear etiologic driver. It is unknown if younger patients have an increased risk of recurrence compared to older patients. A literature search was conducted through January 2020 using PubMed/MEDLINE, Embase, Cochrane, Scopus, Science Direct, and clinicaltrials.gov. This review was registered with PROSPERO (ID: CRD42020167498) and the PRISMA statement was followed. Studies were eligible for inclusion if they assessed risk of recurrence by age using a time-to-event analysis, used an age cutoff of ≤45 years or less for the younger cohort, and limited the analysis to the oral tongue subsite. Data were extracted independently by two reviewers using a form with a prespecified list of variables. There were 13 articles that met criteria for the qualitative synthesis (n = 1763 patients). The reported 5-year rates of disease-free survival ranged from 30% to 72% for the younger cohorts and 42% to 81% for the older cohorts. Three studies reported a statistically significant increased risk of recurrence in younger patients, three studies reported a nonsignificant increased risk in younger patients, and seven studies reported a similar risk in younger patients based on the time-to-event analyses. There may be an increased risk of recurrence for younger patients with oral tongue cancer. A definitive conclusion is precluded by limitations among individual studies, and additional research is warranted to examine this question.

Prognostic and Clinicopathological Significance of FADD Upregulation in Head and Neck Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

Fas-associated death domain (FADD) upregulation, i.e., gene amplification, protein phosphorylation and/or overexpression, has shown promising prognostic implications in head and neck squamous cell carcinoma (HNSCC). This systematic review and meta-analysis aims to evaluate the clinicopathological and prognostic significance of FADD upregulation in HNSCC. We searched studies published before February 2020 through PubMed, Embase, Web of Science, Scopus and Google Scholar. We evaluated the quality of the studies included using the QUIPS tool. The impact of FADD upregulation on survival and clinicopathological variables was meta-analysed. We explored heterogeneity and their sources, conducted sensitivity analyses and investigated small-study effects. Thirteen studies (1,923 patients) met inclusion criteria. FADD immunohistochemical overexpression was statistically associated with worse overall survival (hazard ratio [HR] = 1.52, 95% confidence intervals [CI] = 1.28-1.81, p < 0.001), disease-specific survival (HR = 2.52, 95% CI = 1.61-3.96, p < 0.001), disease-free survival (HR = 1.67, 95% CI=1.29-2.15, p < 0.001), higher clinical stage (odds ratio [OR] = 1.72, 95% CI = 1.17-2.51, p = 0.005) and a large magnitude of effect with N+ status (OR = 2.36, 95% CI = 1.85-3.00, p < 0.001). FADD phosphorylation in ser-194 demonstrated no prognostic value, while no conclusive results can be drawn for FADD gene amplification. In conclusion, our findings indicate that immunohistochemical assessment of FADD overexpression could be incorporated into the prognostic evaluation of HNSCC.

Regulatory mechanism of tumor suppressor gene miR-302b in malignant tumors

MicroRNAs are a class of endogenous non-coding RNA molecules that regulate the translation of proteins. They play important regulatory roles in the growth, development, and aging of organisms, as well as cell proliferation, differentiation, apoptosis, and even cancer. miR-302b can participate in the regulation of the expression of a variety of genes, and functions as a tumor suppressor gene in the occurrence, development, invasion, and metastasis of malignant tumors. This article discusses the expression of miR-302b in malignant tumors and its biological functions and molecular mechanism.

Differential Expression and Prognostic Value of Cytoplasmic and Nuclear Cyclin D1 in Prostate Cancer

Cyclin D1 (CCND1) has been revealed as a key regulating protein in cell cycle (G1 phase) and plays a critical role in promoting tumor development. The purpose of our study was to investigate the associations between CCND1 and biochemical recurrence of prostate cancer (PCa). We performed immunostaining of CCND1 on a tissue microarray and evaluated the CCND1 expression levels based on the intensity and extent of staining. The clinical data was collected, and the follow-up data was received by searching our follow-up database called "PC-follow". We revealed that CCND1 expression patterns were different between cytoplasm and nucleus in this study, and the expression of CCND1 in adjacent normal tissues was higher than that in PCa tissues (P < 0.001), while nuclear CCND1 showed the opposite distribution characteristic (P < 0.001). The cytoplasmic CCND1 also showed correlation with several clinical factors, e.g., tumor T stage (P < 0.001), Gleason score (P = 0.028), positive surgical margin (P = 0.037), and capsule invasion (P = 0.04). We also revealed that cytoplasmic CCND1 is a protective prognostic factor in the biochemical recurrence (BCR) free time analysis (P = 0.002). However, the nuclear CCND1 showed no correlation with clinical factors or prognostic value in this study. This study found that cytoplasmic and nuclear CCND1 have significant different expression patterns in PCa tissues, and cytoplasmic CCND1 has a certain prognostic value in the BCR analysis.

Circular RNA circMDM2 accelerates the glycolysis of oral squamous cell carcinoma by targeting miR-532-3p/HK2

Circular RNAs (circRNAs) function as an essential regulator in the progression of oral squamous cell carcinoma (OSCC). However, the potential roles and mechanism of circRNAs in OSCC are still elusive. Here, this research investigates the roles and molecular mechanism of novel circRNA (circMDM2) in OSCC progression. Clinically, circMDM2 was overexpressed in OSCC tissue and cells, and the overexpression served as a poor prognostic factor for OSCC patients. Functionally, cellular experiments confirmed that circMDM2 accelerated OSCC cell proliferation and glycolysis in vitro and circMDM2 knockdown repressed the tumour growth in vivo. Mechanistically, circMDM2 sponged miR‐532‐3p to promote the hexokinase 2 (HK2), forming the circMDM2/miR‐532‐3p/HK2 axis. In conclusion, these findings demonstrated that circMDM2/miR‐532‐3p/HK2 axis promotes the proliferation and glycolysis of OSCC, rendering a potential diagnostic biomarker and prospective therapeutic target for OSCC.

An update on the implications of cyclin D1 in melanomas

Cyclin D1 is a protein encoded by the CCND1 gene, located on 11q13 chromosome, which is a key component of the physiological regulation of the cell cycle. CCND1/cyclin D1 is upregulated in several types of human tumors including melanoma and is currently classified as an oncogene that promotes uncontrolled cell proliferation. Despite the demonstrated importance of CCND1/cyclin D1 as a central oncogene in several types of human tumors, its knowledge in melanoma is still limited. This review examines data published on upregulation of the CCND1 gene and cyclin D1 protein in the melanoma setting, focusing on the pathways and molecular mechanisms involved in the activation of the gene and on the clinical and therapeutic implications.

Clinico-pathological significance of Drp1 dysregulation and its correlation to apoptosis in oral cancer patients

Dysregulation in mitochondrial dynamics has been associated with several diseases including cancer. Present study assessed the alteration in mitochondrial fission protein (Drp1) in oral epithelial cells collected from clinically confirmed pre-cancer and cancer patients and further correlates it with the cellular apoptosis signaling. Results indicate the ROS accumulation in OSCC patients is accompanied by several changes including increase in mitochondrial mass, expression of mitochondrial fission protein (Drp1) and alteration in apoptotic signaling. The positive co-relation has been observed between the expressions of anti-apoptotic Bcl-2proteinswith mitochondrial fission protein Drp1. Higher mitochondrial fission in oral cancer cells was also correlated with the increased expression of cell cycle marker CyclinD1 indicating highly proliferative stage of oral cancer cells. The clinical correlation can be extended to develop biomarker for diagram and program in oral cancer management.

Diabetes mellitus and oral cancer/oral potentially malignant disorders: A systematic review and meta-analysis

The objective was to evaluate current evidence on the prevalence and risk of oral cancer and potentially malignant oral disorders among patients with diabetes mellitus. We searched PubMed, Embase, Web of Science, and Scopus for observational studies published before November 2019. We evaluated the study quality using GRADE, QUIPS, and a specific method for systematic reviews addressing prevalence questions. Meta-analyses were conducted, and heterogeneity and publication bias were examined. A total of 1,489 studies were found, 116 analyzed in full text, 52 included in qualitative synthesis and 49 meta-analyzed. Pooled prevalence (PP) of oral cancer in patients with diabetic was 0.25% (95% CI = 0.15-0.39)-250 per 100,000 patients with diabetes mellitus -with a greater chance of oral cancer among patients with diabetes mellitus (OR = 1.41 [95% CI = 1.10-1.81], p = .007). Patients with oral cancer and diabetes mellitus had a higher mortality than controls (HR = 2.09 [95%CI = 1.36-3.22], p = .001). Leukoplakia had a PP = 2.49% (95% CI = 1.14-4.29)-2,490 per 100,000 patients with diabetes mellitus -(OR = 4.34 [95% CI = 1.14-16.55], p = .03). A PP of 2.72 (95% CI = 1.64-4.02) was obtained for oral lichen planus among patients with diabetic -2,720 per 100,000 patients with diabetes mellitus (OR = 1.87 [95% CI = 1.37-2.57], p < .001). A low PP was estimated for erythroplakia (0.02%[95%CI = 0.00-0.12]-20 per 100,000 patients with diabetes mellitus. In conclusion, patients with diabetes mellitus have a higher prevalence and greater chance of oral cancer and OPMD development in comparison with non-diabetic patients. In addition, patients with oral cancer suffering from diabetes mellitus have a higher mortality compared to non-diabetic patients with oral cancer.

Molecular biology of oral cavity squamous cell carcinoma

Oral cavity squamous cell carcinoma (OCSCC) is a heterogeneous and complex disease that arises due to dysfunction of multiple molecular signaling pathways. Recent advances in high-throughput genetic sequencing technologies coupled with innovative analytical techniques have begun to characterize the molecular determinants driving OCSCC. An understanding of the key molecular signaling networks underlying the initiation and progression of is essential for informing treatment of the disease. In this chapter, we discuss recent findings of key genes altered in OCSCC and potential treatments targeting these genes.

The double dealing of cyclin D1

The cell cycle is tightly regulated by cyclins and their catalytic moieties, the cyclin-dependent kinases (CDKs). Cyclin D1, in association with CDK4/6, acts as a mitogenic sensor and integrates extracellular mitogenic signals and cell cycle progression. When deregulated (overexpressed, accumulated, inappropriately located), cyclin D1 becomes an oncogene and is recognized as a driver of solid tumors and hemopathies. Recent studies on the oncogenic roles of cyclin D1 reported non-canonical functions dependent on the partners of cyclin D1 and its location within tumor cells or tissues. Support for these new functions was provided by various mouse models of oncogenesis. Finally, proteomic and transcriptomic data identified complex cyclin D1 networks. This review focuses on these aspects of cyclin D1 pathophysiology, which may be crucial for targeted therapy.Abbreviations: aa, amino acid; AR, androgen receptor; ATM, ataxia telangectasia mutant; ATR, ATM and Rad3-related; CDK, cyclin-dependent kinase; ChREBP, carbohydrate response element binding protein; CIP, CDK-interacting protein; CHK1/2, checkpoint kinase 1/2; CKI, CDK inhibitor; DDR, DNA damage response; DMP1, cyclin D-binding myb-like protein; DSB, double-strand DNA break; DNA-PK, DNA-dependent protein kinase; ER, estrogen receptor; FASN, fatty acid synthase; GSK3β, glycogen synthase-3β; HAT, histone acetyltransferase; HDAC, histone deacetylase; HK2, hexokinase 2; HNF4α, and hepatocyte nuclear factor 4α; HR, homologous recombination; IR, ionizing radiation; KIP, kinase inhibitory protein; MCL, mantle cell lymphoma; NHEJ, non-homologous end-joining; PCAF, p300/CREB binding-associated protein; PGC1α, PPARγ co-activator 1α; PEST, proline-glutamic acid-serine-threonine, PK, pyruvate kinase; PPAR, peroxisome proliferator-activated receptor; RB1, retinoblastoma protein; ROS, reactive oxygen species; SRC, steroid receptor coactivator; STAT, signal transducer and activator of transcription; TGFβ, transforming growth factor β; UPS, ubiquitin-proteasome system; USP22, ubiquitin-specific peptidase 22; XPO1 (or CRM1) exportin 1.

[Effect of circular RNA hsa_circ_0002203 on the proliferation, migration, invasion, and apoptosis of oral squamous cell carcinoma cells]

OBJECTIVE

To investigate the effect of circular RNA hsa_circ_0002203 on the malignant biological behavior of oral squamous cell carcinoma (OSCC) cell lines.

METHODS

Forty patients with oral squamous cell carcinoma were included. Real-time fluorescent polymerase chain reaction (PCR） was used to detect the expression level of circular RNA hsa_circ_
0002203 in OSCC and corresponding adjacent tissues, OSCC cell lines, and human oral keratinocytes (HOK). SCC15 and CAL27 cells were transfected with lenti-virus. The expression level of circular RNA hsa_circ_0002203 was detected by real-time fluorescent PCR. Cell proliferation was detected by cell counting assay (CCK-8). Cell migration and invasion ability was detected by scratch assay and Transwell migration and invasion assay. Apoptosis level was detected by flow cytometry. The expression of corresponding protein was detected by Western blot. Murine tumor formation experiments were performed to observe the effect of hsa_circ_0002203 on the tumorigenesis of SCC15 cells in vivo.

RESULTS

The expression of circular RNA hsa_circ_0002203 in OSCC tissues was lower than that in adjacent tissues (P<0.01), and the expression in OSCC cell lines was lower than that in HOK (P<0.001). Hsa_circ_
0002203 expression increased after the lentiviral infection of SCC15 and CAL27. The proliferation, migration, and invasion of SCC15 and CAL27 reduced, and apoptosis level was promoted. The tumor volume, weight decreased, and growth rate of nude mice decreased.

CONCLUSIONS

The low expression of circular RNA hsa_circ_0002203 in oral squamous cell carcinoma can enhance the proliferation, migration, and invasion of cancer cells and inhibit tumor cell apoptosis.

Integrative analysis of gene alterations and immunoexpression profiles of cell cycle checkpoints in oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) represents 95% of all cancers of the head and neck region. The five-year survival rate of OSCC patients is about 60% and has not gone throw significant improvements despite recent advances in molecular biology, or the identification of key pathways in its pathophysiology such as cell cycle.

OBJECTIVE

1) to analyse the inmunoexpression of cell cycle checkpoints (CPs) in an OSCC institutional cohort and to relate it to clinicopathological features and survival, and 2) to study CPs-related genes in the OSCC subset of the TCGA database.

METHODS

Immunohistochemistry (IHC) for p16INK4a, p21CIP1, cyclin D1 and p27KIP1 protein expression was quantified by tissue microarray analysis in 68 samples from OSCC patients. In order to analyse its correlation with genetic information, a cohort belonging to The Cancer Genome Atlas (TCGA) database was analysed.

RESULTS

Of 68 patients, 34 (50%) developed recurrence, and 36 (52.09%) died as a result of disease progression (mean survival 34.09 months). IHC staining for nuclear cyclin D1 was associated with worse staging and tobacco use. p16INK4a, p21CIP1, cyclin D1, and p27KIP1 expression was unrelated to overall survival. No statistically significant correlation linked the CPs-related genes mutations to OSCC overall survival in the TCGA database.

CONCLUSIONS

CPs variations at a phenotype and genotype level seem not to affect significantly clinicopathological features and survival in the studied OSCC cohorts.

Tumor-suppressor gene SOX1 is a methylation-specific expression gene in cervical adenocarcinoma

The present study is to analyze the difference of gene methylation in early cervical adenocarcinoma and to find molecular markers for predicting the occurrence and development of cervical adenocarcinoma.A total of 15 cases of primary cervical adenocarcinoma and 10 cases of primary cervical squamous cell carcinoma at stages IB1 or IIA1 were included in the study. Infinium MethylationEPIC BeadChip (850K) was used to screen specifically expressed genes in cervical adenocarcinoma tissues. Bisulfite sequencing polymerase chain reaction (BSP) and quantitative real-time polymerase chain reaction (qRT-PCR) were used to verify the methylation levels in cervical adenocarcinoma, cervical squamous cell carcinoma, and normal cervical tissues.Sex determining region Y-box 1 (SOX1) and cyclin D1 (CCND1) genes participated in multiple signaling pathways, being the central nodes of gene regulatory networks. SOX1 gene, but not CCND1 gene, was a specifically methylated gene in cervical adenocarcinoma according to BSP. According to qRT-PCR, methylation level of SOX1 in cervical adenocarcinoma tissues is significantly different from that in cervical squamous cell carcinoma tissues or normal cervical tissues, and the methylation level of CCND1 in cervical adenocarcinoma tissues or cervical squamous cell carcinoma tissues is significantly different from that in normal cervical tissues.The present study demonstrates that tumor-suppressor gene SOX1 is a methylation-specific expression gene of cervical adenocarcinoma and is expected to become a specific molecular marker for the diagnosis of cervical adenocarcinoma. However, CCND1 gene was not proven to be a specific methylation expression gene in cervical adenocarcinoma in the present study.

Hsa_circ_0005379 regulates malignant behavior of oral squamous cell carcinoma through the EGFR pathway

Background

Oral squamous cell carcinoma (OSCC) is an oral and maxillofacial malignancy with a high incidence worldwide. Accumulating evidence indicates that circular RNAs (circRNAs) play a vital role in modulating tumor development. However, the mechanism of circRNA action in human OSCC remains largely unknown.

Methods

By using high-throughput transcriptome sequencing technology, we conducted a comprehensive study of circRNAs in human OSCC. The effect of circRNA hsa_circ_0005379 on OSCC tissues and cell lines was monitored by qRT-PCR, Transwell assay, flow cytometry, and western blot analysis. Xenograft mouse models were used to assess tumor growth and animal survival.

Results

We found that circRNA hsa_circ_0005379 expression is significantly lower in OSCC tissue compared to paired non-cancerous matched tissue and is associated with tumor size and differentiation. Overexpression of hsa_circ_0005379 effectively inhibits migration, invasion, and proliferation of OSCC cells in vitro and suppresses OSCC growth in nude mice in vivo. Mechanistic studies revealed that hsa_circ_0005379 may be involved in the regulation of the epidermal growth factor receptor (EGFR) pathway. Furthermore, we found that high expression of hsa_circ_0005379 could significantly enhance the sensitivity of OSCC to the cetuximab drug.

Conclusions

Our findings provide evidence that hsa_circ_0005379 regulates OSCC malignancy and may be a new therapeutic target for OSCC treatment.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5593-5) contains supplementary material, which is available to authorized users.

Prognostic role of cyclin D2/D3 in multiple human malignant neoplasms: A systematic review and meta-analysis

Cyclin D2/D3 (CCND2/3) are core components of the machinery that drives cell cycle progression and therefore, are associated with tumorigenesis. Currently, there are contradictory evidences on the function of CCND2/3 in tumorigenesis. Thus, we conducted a comprehensive meta‐analysis to derive a precise predictive value of CCND2/3 in various tumors. We searched PubMed, EMBASE, Web of Science for eligible studies up to October 8, 2018. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) of OS or DFS/PFS/RFS were calculated using Forest plot analysis to demonstrate their associations. A total of 14 studies were ultimately included in this meta‐analysis. Our results indicated CCND2/3 played an oncogenic role in all of the cancer patients (CCND2: pooled HR = 2.21, 95% CI: 1.67‐2.93; CCND3: pooled HR = 2.29, 95% CI: 1.05‐5.03). In tumor subgroup, CCND2 was associated with shorter OS in patients with gastric cancer (HR = 2.20, 95% CI: 1.66‐2.92), whereas it might be a tumor suppressor in NSCLC (HR = 0.28, 95% CI: 0.12‐0.64). In addition, CCND3 was correlated to reduced OS in breast cancer patients (HR = 1.64, 95% CI: 1.07‐2.52) and shorter DFS/PFS/RFS in bladder cancer patients (HR = 4.60, 95% CI: 1.89‐12.57). Taken together, CCND2/3 could be the promising biomarkers for predicting the prognosis of patients with malignant neoplasms.

Long non-coding RNA highly up-regulated in liver cancer promotes epithelial-to-mesenchymal transition process in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is an oral and maxillofacial malignancy that exhibits high incidence worldwide. In diverse human cancers, the long non-coding RNA (lncRNA) highly up-regulated in liver cancer (HULC) is aberrantly expressed, but how HULC affects OSCC development and progression has remained mostly unknown. We report that HULC was abnormally up-regulated in oral cancer tissues and OSCC cell lines, and that suppression of HULC expression in OSCC cells not only inhibited the proliferation, drug tolerance, migration and invasion of the cancer cells, but also increased their apoptosis rate. Notably, in a mouse xenograft model, HULC depletion reduced tumorigenicity and inhibited the epithelial-to-mesenchymal transition process. Collectively, our findings reveal a crucial role of the lncRNA HULC in regulating oral cancer carcinogenesis and tumour progression, and thus suggest that HULC could serve as a novel therapeutic target for OSCC.

Knockdown of MALAT1 inhibits osteosarcoma progression via regulating the miR‑34a/cyclin D1 axis

Long non-coding (lnc)RNAs have been demonstrated to be involved in the development of various types of cancers, such as osteosarcoma (OS). Long non-coding (lnc) RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT1) expression was reported to be highly expressed in OS and promoted the development of this disease; however, the underlying molecular mechanism by which MALAT1 promotes the progression of OS requires further investigation. In the present study, the expression of MALAT1 and miR-34a was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The abundance of cyclin D1 (CCND1) was detected by RT-qPCR and western blotting. Cell viability, migration and invasion were examined by MTT and Transwell assays. The interaction between miR-34a and MALAT1 or CCND1 was probed by a dual luciferase reporter assay and RNA immunoprecipitation. Xenograft tumor assay was performed to verify the roles of MALAT1 and miR-34a in tumor growth in vivo. The results demonstrated that MALAT1 and CCND1 mRNA expression levels were upregulated and miR-34a was downregulated in OS tissues and cells. Additionally, MALAT1 expression was correlated with tumor size, clinical stage and distant metastasis in patients with OS. In addition, MALAT1 promoted OS cell viability, invasion and migration, while MALAT1 silencing exhibited opposing effects. Moreover, MALAT1 functioned as a ceRNA to suppress miR-34a expression and in turn upregulate CCND1 in OS cells. Rescue experiments further demonstrated that MALAT1 knockdown partially reversed anti-miR-34a-mediated promotion on OS cell viability, migration and invasion; overexpression of CCND1 partially reversed the effects of MALAT1 silencing on OS progression. Furthermore, in vivo experiments also revealed that MALAT1 promoted OS tumor growth via miR-34a inhibition and upregulating the expression of CCND1. In conclusion, the present study suggested that MALAT1 exerted its oncogenic function in OS by regulating the miR-34a/CCND1 axis in OS, which may provide novel insight into the diagnosis and therapy for OS.