Alterations in MDM2 expression in esophageal squamous cell carcinoma: Relationship with p53 status

In view of the significance of MDM2 as a regulator as well as critical target of wild type p53, this study was undertaken to determine the alteration in MDM2 expression in esophageal squamons cell carcinoma (ESCC) and its relationship to clinicopathological parameters as well as p53gene and protein status. Immunohistochemical analysis of MDM2 and p53 proteins on paraffin embedded sections from 64 surgically resected ESCCs and matched histologically normal tissues showed overexpression of MDM2 protein in 23/64 (36%) ESCCs, while the histopathologically normal esophageal tissues did not show detectable level of MDM2 immunoreactivity. Interestingly, MDM2 /p53 + phenotype was observed in 37/64 (58%) cases. None of the cases with p53 mis-sense mutations (12/30, 40%) showed detectable level of MDM2 protein. Missense p53 mutations were significantly associated with discordant p53 + /MDM2 immunophenotype (p= 0.004). The most intriguing feature of the study was accumulation of MDM2 in the absence of detectable p53 in 11% of and overexpression of MDM2 and p53 in 25% of ESCCs, suggesting a p53-independent role for MDM2 in a subset of tumors. These results underscore the involvement of MDM2 in p53-dependent and -independent pathways in the pathogenesis of esophageal cancer in the Indian population.     

PKM2在食管鳞癌组织中的表达及其临床意义

目的:探讨食管癌中丙酮酸激酶2(PKM2)的表达情况及临床意义.方法:收集川北医学院附属医院外科手术切除并经病理确诊的食管鳞癌30例(其中高分化9例、中分化10例、低分化11例)及正常组织(包含切缘组织)标本30例,采用免疫组化方法检测PKM2的表达.结果:PKM2在正常食管组织、切缘组织、食管鳞癌组织中的阳性表达率分别为0、0、90％,PKM2在食管鳞癌组织中的表达与正常组织、切缘组织的表达差异有统计学意义(P＜0.001).在食管癌鳞癌中,不同浸润程度的食管鳞癌组织PKM2的表达差异有统计学意义.PKM2的表达水平在不同分化程度、是否淋巴结转移中的差异无显著性意义.结论:PKM2在食管鳞癌组织中存在显著高表达.     

Effects of MDM2 promoter polymorphisms and p53 codon 72 polymorphism on risk and age at onset of squamous cell carcinoma of the head and neck

Both p53 tumor suppressor and murine double minute 2 (MDM2) oncoprotein are crucial in carcinogenesis. We hypothesized that MDM2 promoter single nucleotide polymorphisms (SNPs) SNP309 T > G, A2164G, and p53 codon 72 are associated with risk and age at onset of squamous cell carcinoma of head and neck (SCCHN). We genotyped these SNPs in a study of 1,083 Caucasian SCCHN cases and 1,090 cancer-free controls. Although none of these SNPs individually had a significant effect on risk of SCCHN, nor did their combined putative risk genotypes (i.e., MDM2 SNP309 GT + GG, 2164 AA, and p53 codon 72 CC), we found that individuals with two to three risk genotypes had significantly increased risk of non-oropharyngeal cancer (OR = 1.42; 95% CI = 1.07-1.88). This increased risk was more pronounced among young subjects, men, smokers, and drinkers. In addition, female patients carrying the MDM2 SNP309 GT and GG genotypes showed a 3-yr (56.7 yr) and 9-yr (51.2 yr) earlier age at onset of non-oropharyngeal cancer (P(trend) = 0.007), respectively, compared with those carrying the TT genotype (60.1 yr). The youngest age (42.5 yr) at onset of non-oropharyngeal cancer was observed in female patients with the combined MDM2 SNP309 GG and p53 codon 72 CC genotypes. The findings suggest that MDM2 SNP309, A2164G, and p53 codon 72 SNPs may collectively contribute to non-oropharyngeal cancer risk and that MDM2 SNP309 individually or in combination with p53 codon 72 may accelerate the development of non-oropharyngeal cancer in women. Further studies with large sample sizes are warranted to validate these results.     

Functional characterization of p53 molecules expressed in human squamous cell carcinomas of the head and neck

Mutation of the p53 tumor suppressor gene has been demonstrated in a large proportion of human head and neck squamous cell carcinomas (HNSCCs) and has been assumed to play a role in the pathogenesis of these tumors, although no formal evidence of functional aberration has been demonstrated. In this study, we isolated cDNA clones encoding the entire p53 coding region from six human HNSCC cell lines that showed aberrant patterns of p53 expression in the parental cells, analyzed their nucleotide sequences, and characterized their function in vivo. cDNAs cloned from four cell lines harbored alterations within the p53 coding sequence (one missense mutation, one missense mutation plus in-frame deletion, one splice donor mutation, and a 1-nt insertion). HN30 cells, which contained wild-type p53 nucleotide sequences, showed a high constitutive level of protein expression. HN26 cells contained wild-type coding sequences but did not express the 53-kDa protein, although the mRNA was transcribed and a molecule of increased molecular mass (70 kDa) was observed by western blotting. Functional studies revealed that none of the four proteins encoded by mutant cDNAs were able to transactivate expression of a reporter plasmid containing a wild-type p53 consensus binding site when cotransfected into p53-null cells, whereas molecules encoded by wild-type p53 cDNAs increased reporter gene expression about a hundredfold over uninduced levels. Co-expression of each mutant cDNA with wild-type p53 cDNA and a wild-type p53-responsive reporter gene demonstrated that each of the proteins encoded by mutant cDNAs harbored some degree of inhibitory activity that varied depending on the mutation present. Thus, aberrant p53 function as a result of mutation or altered expression characterizes oral squamous cell carcinomas. The inhibitory activity of these molecules may be a mechanism for deregulation of the function of co-expressed wild-type p53 that may be of importance during the early stages of tumor development. Mol. Carcinog. 18:89–96, 1997. © 1997 Wiley-Liss, Inc.     

Loss of MTBP expression is associated with reduced survival in a biomarker-defined subset of patients with squamous cell carcinoma of the head and neck

BACKGROUND:

Recent genetic studies have implicated p53 mutation as a significant risk factor for therapeutic failure in squamous cell carcinoma of the head and neck (SCCHN). However, in a recent meta‐analysis in the literature of p53 from major anatomical subsites (larynx, oral cavity, oropharynx/hypopharynx), associations between patient survival and p53 status were ambiguous.

METHODS:

The authors examined a cohort of SCCHNs using a previously developed biomarker combination that likely predicts p53 status based on p53/MDM2 expression levels determined by immunohistochemistry (IHC). In addition, the authors generated and validated an antibody to MTBP (an MDM2 binding protein that alters p53/MDM2 homeostasis and may contribute to metastatic suppression) and have incorporated data for MTBP expression into the current analyses.

RESULTS:

Analysis of expression data for p53 and MDM2 in 198 SCCHN patient samples revealed that the biomarker combination p53 + ve/MDM2‐low (likely indicative of p53 mutation) was significantly associated with reduced overall survival (log‐rank P = .035) and was an independent prognostic factor (P = .013; HR, 1.705; 95% CI, 1.12‐2.60); thus, these data were compatible with earlier genetic analyses. By using IHC for p53 and MDM2 to dichotomize patients, the authors found that loss of MTBP expression was significantly associated with reduced survival (log‐rank P = .004) and was an independent prognostic factor (P = .004; HR, 2.78; 95% CI, 1.39‐5.54) in p53 + ve/MDM2‐low patients.

CONCLUSIONS:

These results represent the first examination of MTBP expression in human tissues and provide evidence for a p53 status‐dependent role for MTBP in suppressing disease progression in SCCHN patients as well as confirming a role for p53 pathway function in delaying disease progression. Cancer 2011. © 2011 American Cancer Society.     

外阴鳞癌动物模型的建立及MDM2表达的研究

目的:探讨外阴鳞癌动物模型建立的方法,研究在鼠外阴癌变发生、演进过程中MDM2的表达变化。方法:采用苯甲酸雌二醇注入32只129/J型鼠腹部皮下,8只为对照组,观测肿瘤的体积,取材做病理诊断。采用RT-PCR技术检测MDM2基因的mRNA表达。结果:外阴上皮内瘤变(VIN)发生率为65.5%(19/29),其中VIN1、VIN2各5例,VIN39例;外阴鳞状细胞癌(VSCC)发生率为34.5%。VIN1～2、VIN3、VSCC和对照组中,MDM2基因的mRNA的相对表达量分别为0.34±0.11、0.42±0.20、1.84±0.32和0.30±0.01;VSCC分别与VIN1～2、VIN3和对照组相比,差异均有统计学意义(P<0.05)。结论:129/J型鼠可为外阴病变(VINs/VSCC)的研究提供动物模型。MDM2在鼠外阴鳞癌中的变化与人组织相同,MDM2可作为外阴癌变的生物学指标。     

Heat-induced growth inhibition and apoptosis in transplanted human head and neck squamous cell carcinomas with different status of p53

To examine p53-dependency in hyperthermic cancer therapy, heat-induced growth inhibition and apoptosis in transplanted human head and neck squamous cell carcinoma (HNSCC) tumours were analysed with different status of p53 into nude mice. The tumour tissue from HNSCC cell line (SAS) transfected with mutant p53 gene (SAS/mp53) or control vector containing neo gene (SAS/neo) was transplanted into the subcutaneous tissue of the thigh of nude mice using a trocar. Hyperthermia was performed at 42°C when the mean diameter of tumour was 5–6?mm. The diameter of tumours was measured using vernier calipers and tumour weight (TW) and the relative tumour weight (RW) was calculated. Tumour regrowth delay was evaluated when the RW reached 5-fold against the control group. The accumulation of p53 and Bax proteins was examined by an immunohistochemical technique. Apoptotic cells in the sections were detected by staining of DNA ends using an immunohistochemical technique. SAS/mp53 tumours showed more heat-resistance than SAS/neo tumours. The p53-positively staining cells were observed in untreated SAS/mp53 tumours, but not in untreated SAS/neo tumours. After heat treatment, the accumulation of p53 and Bax proteins was observed in SAS/neo tumours, but little in SAS/mp53 tumours. The incidence of apoptotic cells induced by heat treatment was very low in SAS/mp53 tumours compared with SAS/neo tumours. In conclusion, the heat-induced growth inhibition of a transplanted HNSCC may be correlated with the induction of p53-dependent Bax-mediated apoptosis. Thus, p53 status appears to be one of the useful parameters for the predictive assays in hyperthermic cancer therapy.     

IRF2在食管鳞癌中的表达及临床意义

目的:探讨干扰素调节因子2（interferon regulatory factor 2,IRF2）在人食管鳞癌组织中的表达及其与病理特征和预后的关系。方法:采用免疫组化SP法检测69例食管鳞癌组织和45 例癌旁组织的IRF2 表达,分析其与临床病理特征及预后之间的关系。结果:IRF2在食管鳞癌组织中的表达明显高于癌旁组织,并与肿瘤分化程度、淋巴转移及TNM分期明显相关。单因素生存分析发现IRF2表达、分化程度、淋巴转移与患者的无进展生存显著相关,多因素分析则证实IRF2是预后的独立风险因子。结论:IRF2在食管鳞癌中高表达,并且是不良预后的独立风险因子,提示其可能发挥癌基因的功能。     

CtBP2 在食管鳞状细胞癌中的表达及其临床意义*

目的：研究羧基末端结合蛋白2（C-terminal binding protein 2,CtBP2）在食管鳞状细胞癌组织中的表达情况及其与食管癌发生发展的关系。方法：Westernblot法检测8 对食管鳞状细胞癌新鲜冰冻组织、免疫组化法检测90例食管鳞状细胞癌石蜡切片组织中CtBP2 表达情况,结合临床病理和随访资料分析CtBP2 表达与患者临床病理参数及总生存率的关系。结果：两法检测结果均显示CtBP2 食管鳞状细胞癌组织中的表达明显高于对应的癌旁组织,且CtBP2 的表达水平与食管癌的组织学分级（P =0.002）、浸润深度（P = 0.032）相关,而与年龄、性别等参数无相关性。Kaplan-Meier 分析结果显示,CtBP2 高表达组患者的总体生存率明显低于CtBP2 低表达组患者。结论：CtBP2 在食管鳞状细胞癌组织中表达显著上调,提示其可能与食管鳞状细胞癌的发生发展相关。     

Functional characterization in vivo of mutant p53 molecules derived from squamous cell carcinomas of the head and neck

Loss of wild-type p53, either through deletion or mutation, has been demonstrated in most squamous cell carcinomas of the head and neck (HNSCC). Whether these mutant molecules contribute to tumor progression purely through loss of wild-type functions or by growth-promoting mechanisms, however, remains unclear. To begin to address these issues, we isolated a series of p53 cDNAs from HNSCC cell lines that contain missense or nonsense point mutations, insertions, or deletions. The ability of each of these molecules to transform NIH/3T3 cells to a malignant phenotype was assessed by stable transfection and expression under the control of a strong heterologous promoter. NIH/3T3 cells transfected with pLTR6p53, which harbors an H179L missense mutation, formed large tumors rapidly (in less than 4 wk) when transplanted to athymic mice, as did cells expressing pLTR13p53, which had undergone a V173F missense mutation and an in-frame deletion of 48 bp between codons 208 and 223. Cells transfected with pLTR17p53, predicted from the nucleotide sequence to encode a severely truncated p53 corresponding to the N-terminal 56 amino acids, also formed tumors. Cells transfected with pLTR15p53, which was predicted to encode a less severely truncated molecule, formed much smaller tumors and at lower frequencies. NIH/3T3 cells transfected with pLTR12p53 (exon 7 splice donor mutant), pLTRwtp53 (wild-type p53), or vector alone failed to form tumors for up to 2 mo after transplantation. pLTR6p53-transfected cells exhibited a highly malignant phenotype with invasion of regional lymph nodes, mediastinal and lung metastases, invasion of the abdominal wall, and dissemination throughout the peritoneal cavity. Histological asssessment of the tumors revealed intensely vascularized fibrosarcomas with numerous cellular atypia, including frequent and aberrant mitoses. Tumor explants were recultured, and northern blot analysis of cellular RNA confirmed that the expression of exogenous p53 was maintained in each case. These data indicate that different p53 mutants contribute to tumorigenesis by specific mechanisms. Furthermore, the results obtained by using the pLTR17p53 transfectants imply that some truncated molecules may overcome the effects of wild-type p53 to contribute to malignancy. Mol. Carcinog. 18:78–88, 1997. © 1977 Wiley-Liss, Inc.     

BRF2 基因在食管鳞状细胞癌组织中的表达及其临床意义

目的:检测TFIIB相关因子2(TFIIB-related factor 2,BRF2)基因在人食管鳞状细胞组织、癌旁组织及正常食管组织中的表达,分析BRF2在食管鳞状细胞癌发生、发展及预后中的意义。方法:选取2007年1月至2008年1月在山东大学齐鲁医院胸外科行手术治疗的食管鳞状细胞患者74例,应用RT-PCR和免疫组化方法检测食管鳞状细胞组织、癌旁组织和正常食管组织中BRF2 mRNA和蛋白表达水平。结果:食管鳞状细胞癌及其癌旁组织中BRF2 mRNA表达水平明显高于正常食管组织。食管鳞状细胞组织、癌旁组织和正常食管组织中BRF2蛋白表达阳性率分别为54.5%、32.5%和7.5%,癌组织、癌旁组织中BRF2蛋白的阳性率均显著高于正常食管组织(P<0.05)。随着食管鳞状细胞分化程度升高,BRF2蛋白阳性率显著下降,Ⅲ期和Ⅳ期食管鳞状细胞组织中BRF2蛋白阳性率明显高于Ⅰ期和Ⅱ期(72.7%,73.3%vs 35.7%,34.8%,P<0.05),且生存3年以下的食管鳞状细胞癌患者BRF2表达明显高于3年以上者(69.2%vs 38.2%,P<0.05),吸烟患者预后BRF2蛋白阳性率明显高于非吸烟患者(61.1%vs 30.4%,P<0.05)。结论:食管鳞状细胞癌组织高表达BRF2蛋白,BRF2 mRNA和蛋白与患者不良预后相关,可能作为食管鳞状细胞预后判断的参考指标之一。     

Involvement of focal adhesion kinase in cellular invasion of head and neck squamous cell carcinomas via regulation of MMP-2 expression

Focal adhesion kinase (FAK) is considered intimately involved in cancer progression. Our previous research has demonstrated that overexpression of FAK is an early and frequent event in squamous cell carcinomas of the supraglottic larynx, and it is associated with the presence of metastases in cervical lymph nodes. The purpose of this study was to examine the functional role of FAK in the progression of head and neck squamous cell carcinomas (HNSCC). To this end, expression of FAK-related nonkinase (FRNK) or small interfering RNA (siRNA) against FAK was used to disrupt the FAK-induced signal transduction pathways in the HNSCC-derived SCC40 and SCC38 cell lines. Similar phenotypic effects were observed with the two methodological approaches in both cell lines. Decreased cell attachment, motility and invasion were induced by FRNK and FAK siRNA, whereas cell proliferation was not impaired. In addition, increased cell invasion was observed upon FAK overexpression in SCC cells. FRNK expression resulted in a downregulation of MMP-2 and MMP-9 expression. Interestingly, MMP-2 overexpression in FRNK-expressing cells rescued FRNK inhibition of cell invasion. This is the first demonstration of a direct rescue of impaired cell invasion by the re-expression of MMP-2 in a tumour cell type with decreased expression of functional FAK. Collectively, these data reported here support the conclusion that FAK enhances invasion of HNSCC by promoting both increased cell motility and MMP-2 production, thus providing new insights into possible therapeutic intervention strategies.     

ILF2及NF90在口腔鳞状细胞癌中的表达及临床意义

目的 探讨白细胞介素增强结合因子2(Interleukin enhancer-binding factor 2,ILF2)及核因子90(Nuclear fac-tor 90,NF90)在口腔鳞状细胞癌(Oral squamous cell carcinoma,OSCC)中的表达及临床意义.方法 使用免疫组织化学(Im-...     

Prevalence and physical status of human papillomavirus in squamous cell carcinomas of the head and neck

Fresh-frozen biopsies were obtained from 61 patients at diagnosis of squamous cell carcinoma of the head and neck (HNSCC) for study of the prevalence and physical status of human papillomavirus (HPV) DNA. The frequency of HPV DNA and genotypes were determined by SPF10 PCR screening with a general probe hybridization and INNO-LiPA HPV genotyping assay. In addition, a single-phase PCR with primers FAP 59/64 and a nested PCR with primers CP 65/70 and CP 66/69 served to detect particularly cutaneous HPV types. By the sensitive SPF10 PCR and INNO-LiPA assay, 37 of 61 (61%) samples were positive for HPV. HPV-16 was the most frequently detected type (31 of 37, 84%). Multiple infections were found in 8 of 37 (22%) of the HPV-positive samples, and co-infection by HPV-16 and HPV-33 was predominant. No cutaneous HPV types were detected. Patients with HPV-positive tumors had similar prognosis as those with HPV-negative ones. Real-time PCR analysis of the HPV-16 positive samples indicated the presence of integrated (11 of 23, 48%), episomal (8 of 23, 35%) and mixed forms (4 of 23, 17%) of HPV DNA. The viral load of HPV DNA exhibited large variation. The median copy numbers of E6 DNA in tonsillar specimens were approximately 80,000 times higher than that in nontonsillar HNSCC ones. Patients with episomal viral DNA were more frequently found to have large (T3-T4) tumors at diagnosis than were those with integrated or mixed forms.     

PD-L1在头颈部鳞癌中的表达及其临床意义

目的探讨程序性死亡受体配体1(PD-L1)在头颈部鳞癌(HNSCC)组织中的表达及其临床意义。方法收集69例HNSCC患者的肿瘤组织和外周血标本,应用免疫组织化学法检测肿瘤组织中PD-L1的表达情况,应用免疫透射比浊法检测外周血C反应蛋白(CRP)水平,分析PD-L1表达情况与患者临床特征及外周血CRP水平的关系。结果 HNSCC患者的PD-L1阳性表达率为14.5%(10/69),PD-L1阴性表达和PD-L1阳性表达HNSCC患者的1年内远处转移情况和血管内皮生长因子(VEGF)表达状态比较,差异均有统计学意义(P﹤0.05)。PD-L1阴性表达患者的远处无转移生存情况明显优于PD-L1阳性表达患者(P﹤0.01)。PD-L1阳性表达患者的外周血CRP水平低于PD-L1阴性表达患者(P﹤0.05)。结论 PD-L1可能是HNSCC患者的潜在预后生物标志物,并且与机体的免疫状态密切相关。     

Activation of AKT and nuclear accumulation of wild type TP53 and MDM2 in anal squamous cell carcinoma

Human papilloma virus (HPV) infection is considered as an important aetiological factor for anal squamous cell carcinoma (ASCC) but is not sufficient for tumour progression. This carcinoma is poorly understood at the molecular level. Using the largest cohort of cases to date we investigated the molecular mechanisms underlying ASCC development, in particular the roles of TP53, MDM2 and AKT. Viral infection in our cohort occurred at high frequency (73%, 94/128) with HPV16 accounting for the majority (86%, 81/94) of infected cases. Only 4% (5/119) of ASCCs showed TP53 (exons 5-8) mutations, but a high frequency (91%, 100/110) of nuclear protein expression of TP53 was observed. There was a significant association (p < 0.001) between nuclear accumulation of TP53 and MDM2 protein although no MDM2 mutations were found, and copy number was normal. Cellular accumulation of phosphorylated-AKT was observed in 66% (82/125) of ASCCs and an association demonstrated between nuclear accumulation of MDM2 and activated AKT (p < 0.001). We observed a high frequency of copy number gain at PIK3CA (47%), and some coding sequence mutations (4%). Amplification of PIK3CA was associated with presence of phosphorylated-AKT (p= 0.008). There was no association between virus infection and TP53 nuclear accumulation (p = 0.5). However, a significant association was found between infection and MDM2 nuclear staining, and between infection and activated AKT (p = 0.04, p = 0.01, respectively). We propose that activation of AKT, possibly through the PI3K-AKT pathway, is an important component of ASCC tumorigenesis that contributes to MDM2 and TP53 accumulation in the nucleus.     

SRPX2和Rab31在口腔鳞癌组织中的表达、相关性及临床意义

目的 本研究旨在探讨口腔鳞癌组织(Oral squamous cell carcinoma,OSCC)中含Sushi重复蛋白X连锁2(Sushi repeat containing protein X-linked 2,SRPX2)及Ras相关蛋白31(Ras-related protein 31,Rab31)的表达情况,并深入分析两蛋白与疾病发生发展的相关性及临床意义,为今后口腔鳞癌新型靶向药物的研发、预后指标的寻找提供新方向。方法 利用Oncomine数据库比较分析SRPX2和Rab31在OSCC组织和正常口腔黏膜组织(Normal oral mucosa,NOM)组织的表达,收集哈尔滨医科大学附属第一医院2010年—2020年期间保存的OSCC组织标本68例及2018年—2020年间的 非癌症患者NOM 30例,应用免疫组织化学染色检测SRPX2、Rab31在组织中的表达。根据检测结果进一步分析OSCC患者SRPX2和Rab31的相关性及两者阳性表达率与临床病理特征的关系。结果 基于Oncomine数据库分析,OSCC组织中SRPX2和Rab31的阳性表达率均高于NOM组织中表达(P＜0.05)。SRPX2在OSCC组织中表达高于NOM组织表达(70.6% vs. 33.3%,P=0.001);Rab31在OSCC组织中表达同样高于NOM组织表达(66.2% vs. 40.0%,P＜0.05)。在OSCC组织中SRPX2与Rab31的表达具有相关性(P＜0.05)。SRPX2和Rab31的表达与肿瘤分化程度、淋巴结转移相关(P＜0.05)。Kaplan-Meier生存分析显示SRPX2、Rab31与OSCC患者不良预后相关(P＜0.05)。结论 OSCC组织中SRPX2、Rab31显著过表达并存在相关性,提示了两者可以联合作为OSCC预后评估的重要指标、新的药物靶点,为OSCC的治疗带来曙光。     

E2F3在喉鳞状细胞癌中的表达及临床意义

目的：探讨喉鳞癌中E2F3的表达与临床意义,为喉鳞癌的诊断、评估及治疗寻找辅助生物学指标。方法：采用免疫组化方法检测喉鳞癌组织及癌旁正常切缘组织中E2F3表达,结合喉鳞癌各临床参数,用SPSS16.0软件包进行统计分析E2F3表达情况与喉鳞癌各临床特征之间的关系。结果：E2F3在喉鳞癌与癌旁正常切缘中的阳性表达率分别为90.44%（123/136）和27.85%（22/79）,差异具有显著统计学意义（P〈0.001）;E2F3高表达与喉鳞癌患者年龄、临床分期及分型均相关（P〈0.05）。结论：E2F3核表达可能参与喉鳞癌发生发展过程;E2F3浆表达可能贯穿于喉鳞癌发生的整体过程。