Development of tissue-engineered models of oral dysplasia and early invasive oral squamous cell carcinoma

Background:

Current organotypic models of dysplasia and oral squamous cell carcinoma (OSCC) lack the complexity that mimics in vivo tissue. Here we describe a three-dimensional in vitro model of the oral epithelium that replicates tumour progression from dysplasia to an invasive phenotype.

Methods:

The OSCC cell lines were seeded as a cell suspension (D20, Cal27) or as multicellular tumour spheroids (FaDu) with oral fibroblasts on to a de-epidermised acellular dermis to generate tissue-engineered models and compared with patient biopsies.

Results:

The D20 and Cal27 cells generated a model of epithelial dysplasia. Overtime Cal27 cells traversed the basement membrane and invaded the connective tissue to reproduce features of early invasive OSCC. When seeded onto a model of the normal oral mucosa, FaDu spheroids produced a histological picture mimicking carcinoma in situ with severe cellular atypia juxtaposed to normal epithelium.

Conclusion:

It is possible to culture in vitro models with the morphological appearance and histological characteristics of dysplasia and tumour cell invasion seen in vivo using native dermis. Such models could facilitate study of the molecular processes involved in malignant transformation, invasion and tumour growth as well as in vitro testing of new treatments, diagnostic tests and drug delivery systems for OSCC.     

Oncolytic activity of Sindbis virus in human oral squamous carcinoma cells

Background:

Sindbis virus (SIN) infection causes no or only mild symptoms (fever, rash, and arthralgia) in humans. However, SIN has a strong cytopathic effect (CPE) on various cancer cells. This study focuses on the oncolytic activity of SIN AR399 on oral cancer cells compared with reovirus, a well-known oncolytic virus that targets cancer cells.

Methods:

We analysed the cytotoxicity and growth of SIN in 13 oral squamous cell carcinoma (OSCC) cell lines (HSC-2, HSC-3, HSC-4, Ca9-22, H-1, Sa-3, KON, KOSC-2, OK-92, HO-1-N1, SCC-4, SAT, SKN-3) and normal human oral keratinocytes (NHOKs).

Results:

Sindbis virus infection induced CPE in 12 OSCC cell lines at a low multiplicity of infection (MOI) of 0.01, but not in the OSCC cell line, HSC-4 or NHOKs. Sindbis viral growth was not observed in NHOKs, whereas high SIN growth was observed in all OSCC cell lines, including HCS-4. The cytotoxicity and growth of SIN was the same as reovirus at an MOI of 20 in 12 OSCC cell lines. The CPE was shown, by terminal deoxyribonucleotidyl transferase–mediated dUTP nick-end labelling assays, to be apoptotic cell death. Furthermore, quantitative RT-PCR of mRNA in HSC-3 and HSC-4 cells after SIN infection showed that activation of caspases, cytochrome c, and IκBα was associated with SIN-induced apoptosis.

Conclusion:

As a replication-competent oncolytic virus, SIN may be a useful therapeutic modality for oral cancers.     

口腔鳞状细胞癌及癌旁组织中抑癌基因PTEN mRNA表达的定量研究

目的定量研究蛋白酪氨酸磷酸酶（PTEN）mRNA在口腔鳞状细胞癌及对应癌旁正常组织中的表达。了解PTEN基因的表达与口腔癌发生、发展的关系。材料和方法应用实时荧光定量PCR方法检测42例口腔鳞状细胞癌及对应癌旁正常组织中PTENmRNA的表达,Rotor-Gene Real-TimePCRAnalysisSoftware6．0软件进行mRNA定量分析,在SPSS14．0统计软件平台上用配对t检验方法统计检验。结果42例口腔鳞状细胞癌和对应癌旁正常组织中均有PTENmRNA表达。口腔鳞状细胞癌组织中PTENmRNA表达量[1．10±0．13（10gPTEN／logβ-actin）]低于相应癌旁正常组织（1．48±0．28）,差异有统计学意义（P〈0．01）。结论口腔鳞状细胞癌的发生与PTENmRNA表达水平降低有一定关系。     

口腔鳞癌细胞增殖和细胞凋亡的相关性研究

目的：通过观察口腔鳞癌中细胞增殖和细胞凋亡之间的关系,探讨细胞凋亡在口腔鳞癌发生中的作用。方法：利用脱氧核糖核酸末端转移酶介导的dUTP缺口末端标记（TUNEL）技术及增殖细胞核抗原（PC—NA）免疫组织化学染色,对69例（维族36例、汉族33例）口腔鳞癌中的凋亡细胞和增殖细胞进行原位观察和比较。结果：口腔鳞癌不同组织学分级比较,高分化口腔鳞癌与中低分化口腔鳞癌之间增殖指数及凋亡指数均有显著性差异（P〈0．05）,不同部位的口腔鳞癌其增殖指数无显著差异,而舌癌组凋亡指数低于唇癌组和牙龈癌组（P〈0．05）,增殖指数与凋亡指数在口腔鳞癌中呈负相关关系（r=-0．663,P〈0．05）。结论：口腔鳞癌癌变过程不仅存在活跃的细胞增殖,而且存在细胞凋亡之异常,细胞增殖和细胞凋亡平衡失调在舌癌发病中可能起重要作用。     

In vitro effect of iASPP on cell growth of oral tongue squamous cell carcinoma

iASPP is an inhibitory member of the apoptosis-stimulating proteins of P53 （ASPP） family. iASPP is over expressed in several malignant tumors and potentially affects cancer progression. However, the expression and potential role of iASPP in oral tongue squamous cell carcinoma （OTSCC） have not been addressed. In our study, we detected iASPP expression in OTSCC by immunohistochemistry, iASPP expression is up-regulated in OTSCC tissues. Moreover, in clinical pathology specimens, we found that increased iASPP expression correlates with poor differentiation and lymph node metastasis. Using multicellular tumor spheroids （MTS） and flow cytometry, we demonstrated that iASPP down-regulation arrests OTSCC cells at the G0/G1 phase, induces OTSCC cell apoptosis and inhibits OTSCC cell proliferation. These results indicate that iASPP plays a significant role in the progression of OTSCC and may serve as a biomarker or therapeutic target for OTSCC patients.     

Expression of cell cycle markers and human papillomavirus infection in oral squamous cell carcinoma: use of fuzzy neural networks

Our aim was to evaluate in oral squamous cell carcinoma (OSCC) the relationship between some cell cycle markers and HPV infection, conditionally to age, gender and certain habits of patients, and to assess the ability of fuzzy neural networks (FNNs) in building up an adequate predictive model based on logic inference rules. Eighteen cases of OSCC were examined by immunohistochemistry for MIB-1, PCNA and survivin expression; presence of HPV DNA was investigated in exfoliated oral mucosa cells by nested PCR (nPCR, MY09-MY11/GP5-GP6), and HPV genotype was determined by direct DNA sequencing. Data were analyzed by traditional statistics (TS) and FNNs. HPV DNA was found in 9/18 OSCCs (50.0 %) without any significant higher risk of HPV infection with respect to the sociodemographic variables considered (p > 0.2), apart from tobacco smoking, reported in 44.4% of OSCC HPV-positive vs. 100% HPV-negative subjects (p = 0.029). Regarding cell cycle markers, TS and FNN revealed that survivin was expressed significantly more in HPV-negative than in HPV-positive OSCC [root mean-square error (RMSE) = 5.89 x 10(-6), % predicted 100.0]; furthermore, smoking played a protective role for survivin expression in HPV-positive cases (OR = 0.019, 95%CI 0.001-0.723, RMSE = 0.20, % of prevision 94.4). FNN, although on a small sample size, allowed us to confirm data by TS and to hypothesize a different cell cycle pattern for HPV-positive vs. HPV-negative OSCC. In the latter cases, the relevance of apoptotic vs. proliferative markers suggested that they may be related to the different supposed outcome of HPV-negative OSCC and that HPV may have a protective role in the expression level of survivin, especially in tobacco smokers.     

Carvacrol抑制ADAM9在口腔鳞状细胞癌中的表达

目的:探讨carvacrol对口腔鳞状细胞癌中ADAM9表达的影响。方法:蛋白印记法分析carvacrol处理的口腔鳞状细胞癌中的去整合素金属蛋白酶9（ADAM9）蛋白表达。另外,提取40 μmol/L carvacrol处理24小时的UM-SCC-23细胞系和Tca8113细胞系中总RNA进行反转录,利用实时定量PCR（real-time PCR）扩增检测ADAM9基因表达。结果:Carvacrol明显降低UM-SCC-23细胞系和Tca8113细胞系ADAM9的蛋白和基因表达。结论:研究揭示了carvacrol的重要机制,可能为口腔鳞状细胞癌治疗提供新的理论依据。     

Prognostic significance of nm23-H1 expression in oral squamous cell carcinoma

Recent studies indicated nm23-H1 played a role in cancer progression. Therefore, we investigated clinical significance of nm23-H1 expression in oral squamous cell carcinoma (OSCC). In total, 86 OSCC specimens were immunohistochemically stained with nm23-H1-specific monoclonal antibodies. Immunohistochemical staining of nm23-H1 was confirmed by immunoblotting. The relations between nm23-H1 expression and clinicopathologic variables were evaluated by chi(2) analysis. As increased size of primary tumour could escalate metastatic potential and the data of patients at the late T stage might confound statistical analyses, we thus paid special attention to 54 patients at the early T stage of OSCC. Statistical difference of survival was compared by a log-rank test. Immunohistochemically, nm23-H1 expression was detected in 48.8% (42 out of 86) of tumorous specimens. It positively correlated with larger primary tumour size (P=0.03) and inversely with cigarette-smoking habit (P=0.042). In patients at the early T stage, decreased nm23 expression was associated with increased incidence of lymph node metastasis (P=0.004) and indicated poor survival (P=0.014). Tumour nm23-H1 expression is a prognostic factor for predicting better survival in OSCC patients at the early T stage, which may reflect antimetastatic potential of nm23. Therefore, modulation of nm23-H1 expression in cancer cells can provide a novel possibility of improving therapeutic strategy at this stage. In addition, our results further indicated cigarette smoking could aggravate the extent of nm23-H1 expression and possibly disease progression of OSCC patients.     

Beneficial effect of KYP-2047, a propyl-oligopeptidase inhibitor,on oral squamous cell carcinoma

Oral squamous cell-carcinoma (OSCC) is a common cancer which arises from the alveolar ridge, buccal mucosa, and tongue. Among OSCC, the incidence of tongue squamous cell-carcinoma (TSCC) is growing all over the world. Oral carcinogenesis has been linked to genetic mutations, chromosomal aberrations and viral factors. Apoptosis and angiogenesis play a key role in the development of oral cancer. Therefore, it is very important discover new therapeutic strategies to counteract oral cancer progression. This study aimed to investigate the effect of KYP-2047 in an in vitro model of TSCC and in vivo CAL27-xenograft model. Our results demonstrated that KYP-2047 was able to reduce TSCCs cell viability at the concentrations of 50 μM and 100 μM. Additionally, KYP-2047 was able to increase Bax, Bad and caspase-3 expression, whereas Bcl-2 and p53 expression were reduced. Moreover, KYP-2047 significantly reduced vascular-endothelial-growth-factor (VEGF) and endothelial-nitric-oxide-synthase (eNOS) expression. In the vivo xenograft model, KYP-2047 at doses of 1 and 5 mg/kg significantly reduced tumor burden and tumor weight, decreasing also angiogenesis markers VEGF and eNOS. Moreover, KYP-2047 increased Bax and reduced Bcl2 expressions. Thus, KYP-2047 could represent a potential therapeutic treatment to counteract tongue oral-cancer growth, thanks its abilities to modulate angiogenesis and apoptosis pathways.     

朗氏细胞在口腔鳞状细胞癌中的作用(英文)

During the initiation, promotion, and progression of multi-step carcinogenesis, changes in specific host immunological factors have been observed. Although immunology of oral cancer has long been focused on antigens and lymphocytes, the fact remains that the antigen presenting cells, like the Langerhans cells (LCs) of the epithelium are initiators and modulators of the immune response. LCs as sentinels of immune response, have been investigated in several oral mucosal diseases, including cancer. Inadequate presentation of tumor antigens by host dendritic cells is one potential mechanism that allows tumor progression. In this review, the role of LCs in OSCC is discussed. Elucidation of the role of APCs, in particular LCs, may help to better understand the mechanisms underlying anti-tumour immune responses and, improve the effectiveness of anti-cancer immunity in tumour-bearing hosts. This section focuses on the roles LCs in the immunity of cancer and how cancer bypasses the dendritic cell-mediated immune responses, are discussed. Subsequently, the effects of tumor microenviornment on LC’s and their therapeutic implications are elaborated.     

RNA-binding protein CELF1 promotes tumor growth and alters gene expression in oral squamous cell carcinoma

The RNA binding protein CELF1 (also known as CUGBP1) is emerging as a critical regulator of cancer cell proliferation and apoptosis. Here, to provide a global prospective of CELF1 regulation of oral squamous cell carcinoma, we performed RNA-sequencing in oral cancer cells and CELF1 overexpression analysis in non-malignant human oral keratinocytes. Our approaches identified 1283 mRNAs differentially regulated as a function of CELF1 expression and more importantly CELF1 promoted alternative splicing of several target pre-mRNAs, which are known to be involved in various cancer biological processes. Overexpression of CELF1 in non-malignant human oral keratinocytes protected cells against oxidative damage and altered gene expression patterns. Finally, we provide evidence that reduction of CELF1 protein using a xenograft tumorigenesis mouse model decreased tumor growth. Altogether, these data provided a comprehensive view of the CELF1 mRNA regulatory network in oral cancer and suggests that CELF1 and/or its target mRNAs are viable candidates for therapeutic intervention.     

Inhibition of ICAM2 induces radiosensitization in oral squamous cell carcinoma cells

We recently identified genes and molecular pathways related to radioresistance of oral squamous cell carcinoma (OSCC) using Affymetrix GeneChip. The current study focused on the association between one of the target genes, intercellular adhesion molecule 2 (ICAM2), and resistance to X-ray irradiation in OSCC cells, and evaluated the antitumor efficacy of combining ICAM2 small interfering RNA (siRNA) and X-ray irradiation. Downregulation of ICAM2 expression by siRNA enhanced radiosensitivity of OSCC cells with the increased apoptotic phenotype via phosphorylation (ser473) of AKT and activation of caspase-3. Moreover, overexpression of ICAM2 induced greater OSCC cell resistance to the X-ray irradiation with the radioresistance phenotype. These results suggested that ICAM2 silencing is closely related to sensitivity of OSCC cells to radiotherapy, and that ICAM2 may be an effective radiotherapeutic target for this disease.     

High survivin expression is associated with favorable outcome in advanced primary oral squamous cell carcinoma after radiation therapy

Oral squamous cell carcinoma (OSCC) is a solid neoplasm exhibiting aggressive tumor phenotypes with unpredictable biological behavior. Recent studies suggested that high expression of the antiapoptotic protein survivin might be associated with adverse outcome in oral cancer patients. To investigate, whether increased copy numbers of the survivin-encoding gene BIRC5 results in elevated survivin levels and whether BIRC5 and survivin could serve as progression markers in the clinical course of OSCC, tumor tissue microarray analysis was performed applying fluorescence in situ hybridization and immunohistochemistry to 296 OSCC specimens. Gene copy number gain of BIRC5 was detected in 33.9% (150/227) of cases, which correlated significantly with high UICC stage and the presence of lymph node metastases (p = 0.003 and p = 0.001, respectively), but not with unfavorable patients' outcome (p > 0.05) in multivariate analysis. High survivin expression was found in 67.3% (169/251) of cases to predict increased 5- and 10-year overall survival of patients in a multivariate model including UICC stage and age as covariables (p = 0.035 and p = 0.026, respectively). Within a subgroup of patients, who received radiation therapy (n = 121), high survivin expression was found to be the only predictor of favorable 3-, 5- and 10-year overall survival in a multivariate cox regression analysis including UICC stage and age as covariables (p = 0.001, p = 0.004 and p = 0.006, respectively). In conclusion, high survivin expression might be useful to identify OSCC patients, who would benefit from radiotherapy.     

Stathmin guides personalized therapy in oral squamous cell carcinoma

The survival benefit from docetaxel, cisplatin and 5‐fluorouracil (TPF) induction chemotherapy in oral squamous cell carcinoma (OSCC) patients is not satisfactory. Previously, we identified that stathmin, a microtubule‐destabilizing protein, is overexpressed in OSCC. Here, we further investigated its role as a biomarker that impacts on OSCC chemosensitivity. We analyzed the predictive value of stathmin on TPF induction chemotherapy and its impact on OSCC cell chemosensitivity. Then, we further investigated the therapeutic effects of the combination therapy of TPF chemotherapy and PI3K‐AKT‐mTOR inhibitors in vitro and in vivo. We found that OSCC patients with low stathmin expression benefited from TPF induction chemotherapy, while OSCC patients with high stathmin expression could not benefit from TPF induction chemotherapy. Stathmin overexpression promoted cellular proliferation and decreased OSCC cell sensitivity to TPF treatment. In addition, inhibition of the PI3K‐AKT‐mTOR signaling pathway decreased stathmin expression and phosphorylation. The combination therapy of TPF chemotherapy and PI3K‐AKT‐mTOR inhibitors exhibited a potent antitumor effect both in vitro and in vivo. Therefore, stathmin can be used as a predictive biomarker for TPF induction chemotherapy and a combination therapy regimen based on stathmin expression might improve the survival of OSCC patients.     

Prognostic value of nuclear survivin expression in oesophageal squamous cell carcinoma

Survivin, a new member of the family of apoptosis inhibitors, is expressed almost exclusively in proliferating cells, above all in cancers. Subcellular localisation and prognostic implications of the survivin protein have not yet been determined in oesophageal squamous cell carcinoma. The survival of 84 patients with oesophageal squamous cell carcinomas was correlated with the extent of immunohistochemical survivin expression in tumour cell nuclei. Tumours were scored positive when >5% cells stained positive. Patients were followed up for at least 5 years or until death. In normal oesophageal squamous cell epithelium, some cytoplasmic survivin expression was detected in the basal cells, whereas proliferating cells showed nuclear staining of survivin. Nuclear expression of survivin was also detected in 67 cancers (80%). The mean survival for patients of this group (28 months, range 20-36) was significantly less than that for patients without survivin expression in the tumour cell nuclei (108 months, range 62-154, P=0.003). Using univariate analysis, nuclear survivin expression (P=0.003), tumour depth (P=0.001), lymph node metastasis (P=0.003) and stage (P<0.001) were the best predictors of survival. In contrast, cytoplasmic survivin staining was noted in 53 (63%) tumours and had no prognostic relevance. In conclusion, the analysis of nuclear survivin expression identifies subgroups in oesophageal squamous cell cancer with favourable (survivin(-)) or with poor prognosis (survivin(+)). We suggest that the determination of nuclear survivin expression could be used to individualise therapeutic strategies in oesophageal squamous cell cancer in the future.