Laryngeal Squamous Cell Carcinoma Carcinogenesis Research Articles

IGF2BP2 acts as a m6A modification regulator in laryngeal squamous cell carcinoma through facilitating CDK6 mRNA stabilization

Laryngeal squamous cell carcinoma (LSCC) is one of the most commonly seen cancers in the head and neck region with increasing morbidity and mortality globally. N6-methyladenosine (m6A) modification plays a critical role in the carcinogenesis of LSCC. In this study, two datasets from online database were analyzed for differentially expressed genes (DEGs) between LSCC and normal samples. Furthermore, we carried out a series of experiments, including hematoxylin & eosin staining, immunohistochemical (IHC) staining, CCK-8, colony formation, transwell, flow cytometry, xenograft tumor model assays, actinomycin D assay, cycloheximide (CHX) assay, methylated m6A RNA immunoprecipitation (Me-RIP), RNA immunoprecipitation (RIP) assay, to verify the relevant findings in vivo and in vitro. Insulin like growth factor 2 mRNA binding protein 2 (IGF2BP2) was identified as an up-regulated m6A regulator in LSCC samples. Lower IGF2BP2 expression was linked to higher survival probability in LSCC and other head and neck squamous cell carcinoma patients. In LSCC cells, IGF2BP2 knockdown attenuated cancer cell aggressiveness, possibly through modulating cell cycle arrest. In the xenograft tumor model derived from IGF2BP2 knocked-down LSCC cells, IGF2BP2 knockdown inhibited tumor growth. IGF2BP2 up-regulated CDK6 expression through facilitating the stability of CDK6 mRNA and protein. CDK6 knockdown caused no changes in IGF2BP2 expression, but partially eliminated the promotive effects of IGF2BP2 overexpression on LSCC cells’ aggressiveness. Overexpressed IGF2BP2 in LSCC serves as an oncogenic factor, promoting LSCC cell proliferation and invasion in vitro and tumor growth in a xenograft tumor model in vivo through facilitating CDK6 mRNA stabilization.

Immunohistochemical Study of IMP3 Expression in Laryngeal Squamous Cell Carcinoma

BACKGROUND: IMP3 is an RNA binding protein, which is strongly expressed in malignant tumors, promoting tumor cell proliferation. AIM: The aim of the study was to evaluate the expression of IMP3 in laryngeal squamous cell carcinoma (SCC) and to correlate the expression of IMP3 with available clinicopathological data. METHODS: Sixty one total laryngectomy and laryngoscopic biopsies; collected from the Pathology Department, Faculty of Medicine, Cairo University. Two slides were prepared from each paraffin embedded tumor block, one slide for Hematoxylin and Eosin staining, and the other for immunohistochemical staining by IMP3 polyclonal antibody. RESULTS: Thirty-seven cases (60.7%) showed positive IMP3 expression, and a statistically significant correlation was found between IMP3 expressions in normal, dysplastic epithelium/in situ component, and the invasive malignant tumor tissue. Correlations between IMP3 expression and other available clinicopathological data were all non-significant. CONCLUSION: This study suggests that IMP3 might play a role in laryngeal SCC carcinogenesis and progression process from normal to dysplastic to malignant epithelium, and thus IMP3 might be targeted by gene therapy.

Role of T helper 17 cytokines in the tumour immune inflammation response of patients with laryngeal squamous cell carcinoma.

Altered cytokine production can lead to immune dysfunction in patients with cancer. The present study investigated the expression of T helper (Th)17 cytokines in patients with laryngeal squamous cell carcinoma (LSCC) and their clinical significance in providing new therapeutic insights. The prevalence of Th17 cells and their receptors in patients with LSCC was studied using immunohistochemical analysis via tissue microarray technology. Flow cytometry was used to investigate the percentage of Th17 and Th1 cells in peripheral blood mononuclear cells. Furthermore, the proliferation of Th17 cells and Th17-associated cytokines, including interleukin (IL)17, IL23 and RAR-related orphan receptor γt, was analyzed by reverse transcription-quantitative polymerase chain reaction. The results revealed that the prevalence of Th17 cells in patients with LSCC was elevated in their primary tumors, as well as in peripheral blood, compared with that in healthy controls. It was further demonstrated that Th17 cells could be induced and expanded in the tumor microenvironment through cytokines produced by the tumor cells. In conclusion, Th17 cells have a substantial impact on the carcinogenesis of LSCCs, and could serve as a potential therapeutic target to modulate the anti-tumor response in these carcinomas.

MicroRNA‑195 inhibits cell proliferation, migration and invasion in laryngeal squamous cell carcinoma by targeting ROCK1.

Laryngeal carcinoma is the second most common malignancy of the head and neck cancers. The most common type of laryngeal carcinoma comprises laryngeal squamous cell carcinoma (LSCC), which accounts for ~95% of laryngeal carcinoma cases. Despite great progress in diagnostic and therapeutic techniques over the last few decades, the prognosis for patients with LSCC remains poor. A number of studies reported that various miRNAs are dysregulated in LSCC and serve critical roles in LSCC tumorigenesis and tumor development. The present study aimed to evaluate the expression level of microRNA (miR)‑195 and its possible roles in LSCC. Briefly, miR‑195 was downregulated in LSCC tissues and cell lines. In addition, low miR‑195 expression was significantly correlated with lymph node metastasis and TNM stage of LSCC patients. Further study has demonstrated that miR‑195 overexpression suppressed cell proliferation, migration and invasion of LSCC. Moreover, rho‑associated kinase 1 (ROCK1) was identified as a direct target gene of miR‑195. Downregulation of ROCK1 exerted similar roles to that of miR‑195 overexpression in LSCC, suggesting ROCK1 was a direct downstream target of miR‑195. These findings elucidated a novel molecular mechanism for the pathogenic mechanism in LSCC carcinogenesis and progression, and may have a potential role in the treatment of patients with LSCC.

Expression Levels and Clinical Significance of miR-21-5p, miR-let-7a, and miR-34c-5p in Laryngeal Squamous Cell Carcinoma

Objective Altered microRNAs (miRNAs) expression has been found in many cancer types, including laryngeal squamous cell carcinoma (LSCC). The aim of this study was to determine the role and clinical value of three LSCC-related miRs, such as miR-21-5p, miR-let-7a, and miR-34c-5p in a homogeneous cohort of patients with primary LSCC treated by primary surgery. Methods Expression levels of miR-21-5p, miR-let-7a, and miR-34c-5p were detected in 43 pairs of LSCC and adjacent normal tissues by reverse-transcription quantitative PCR. Overall survival and disease-free survival were evaluated using the Kaplan–Meier method, and multivariate analysis was performed using the Cox proportional hazard analysis. Results miR-21-5p is significantly upregulated, while miR-let-7a is significantly downregulated in LSCC tumor tissues compared with the corresponding adjacent normal tissues. The downregulation of miR-34c-5p expression significantly correlated with a shorter disease-free survival and, in the multivariate analysis, low miR-34c-5p expression was associated with an increased risk of recurrence. Conclusions miR-21-5p, miR-let-7a, and miR-34c-5p seem to play a critical role in LSCC carcinogenesis and might have a diagnostic and prognostic clinical value. The miR-let-7a levels could have a predictive role for lymph node metastases and miR-34c-5p might be a promising biomarker of patient outcome.

MiR-148a and miR-375 may serve as predictive biomarkers for early diagnosis of laryngeal carcinoma.

The role of microRNAs (miRs) as possible biomarkers and therapy targets has been extensively investigated in a number of types of cancer. However, the aberrant expression of miRs in laryngeal squamous cell carcinoma (LSCC), particularly during the progression of the disease, is poorly understood. In the present study, the role of miRs as possible novel early pre-diagnostic biomarkers of LSCC was investigated. TaqMan probe stem-loop quantitative polymerase chain reaction was utilized to accurately measure the amount of miR-148a and miR-375 in clinical samples of mild dysplasia, moderate dysplasia, severe dysplasia, cancer in situ, laryngeal cancer and normal epithelial controls. The application of miR-148a and miR-375 as potential predictive biomarkers for early diagnosis of LSCC was analyzed. The results of the present study suggested that miR-148a and miR-375 were significantly upregulated in LSCC tissues, and increased expression of miR-375 was associated with a more aggressive phenotype of LSCC. Additional investigation revealed that miR-148a and miR-375 increased during different dysplasia stages of LSCC carcinogenesis, and high-level expression of miR-148a or miR-375 in patients with laryngeal dysplasia may predict subsequent malignant transformation. miR-148a and miR-375 were significantly upregulated during LSCC carcinogenesis and may serve as possible predictive biomarkers for early diagnosis of LSCC.

Human papillomavirus infection in 674 Chinese patients with laryngeal squamous cell carcinoma.

ObjectivesPrevious reports suggest a strong association between human papillomavirus (HPV) and the etiology of laryngeal squamous cell carcinoma (LSCC). However, clinical data regarding the HPV infection rate among LSCC patients remain largely inconsistent.MethodsIn total, 674 LSCC patients from three major hospitals in Shanghai were enrolled in this study. We determined the patients' HPV infection status using immunohistochemistry and the GenoArray HPV genotyping assay and calculated their long-term survival rate using the Kaplan-Meier method.ResultsThe total P16-positive rate according to immunostaining results was 7.57% (51/674). None of the P16-negative patients were HPV-positive according to the HPV genotyping test. The rate of HPV infection among patients with LSCC was 4.9% (33/674). HPV infection was more common among nonsmokers (P<0.05), nondrinkers (P<0.05), and patients with supraglottic LSCC (P<0.05). Of the 33 HPV-positive patients, 28 (84.8%) were infected with HPV-16, 2 with HPV-18, 1 with HPV-31, 1 with HPV-33 and 1 with HPV-45. The 3-year overall survival rate and progression-free survival rate were higher in HPV-positive than HPV-negative patients, but the difference was not statistically significant (76.3% vs. 70.7%, P = 0.30 and 65.1% vs. 58.3%, P = 0.37, respectively).ConclusionHPV was not a main causal factor in LSCC carcinogenesis in this Chinese population. HPV infection did not alter patients' overall survival or progression-free survival rates in this study.

Overexpression of Aurora-A promotes laryngeal cancer progression by enhancing invasive ability and chromosomal instability

The purpose of the study was to investigate the expression of Aurora-A in human laryngeal squamous cell carcinoma (LSCC) and to explore the effects of Aurora-A silencing on invasion and chromosomal instability in laryngeal cancer HEp-2 cells. The expression of Aurora-A mRNA and protein were studied using reverse transcription-PCR and Western blot in LSCC tissues and corresponding normal epithelium, respectively. In addition, the correlation between Aurora-A expression and clinicopathologic characteristics was analyzed in LSCC patients. Furthermore, HEp-2 cells were transfected with Aurora-A short hairpin RNA and the effects of knockdown of Aurora-A on tumor invasion and chromosomal instability were investigated. The results showed that expression of Aurora-A mRNA was significantly upregulated in laryngeal tumor tissue compared with that in normal tissue (P = 0.001), and overexpression of Aurora-A was found in 64.0% (16 of 25) of the patients by Western blotting. Upregulation of Aurora-A mRNA was significantly correlated with regional lymph node metastasis (P = 0.007) and clinical stage III/IV (P = 0.022). Overexpression of Aurora-A was significantly associated with lymph node metastasis (P = 0.027). Furthermore, disruption of Aurora-A using RNA interference technique suppressed invasive ability and chromosomal instability in HEp-2 cells. In conclusion, Aurora-A expression is elevated in human LSCC and associated with regional lymph node metastasis and late clinical stage. Overexpression of Aurora-A may contribute to LSCC carcinogenesis and progression partially due to enhancement of invasion ability and chromosomal instability.

Loss of heterozygosity on chromosomes 3p,8p,9p and 17p in the progression of squamous cell carcinoma of the larynx.

Previous molecular genetic studies of laryngeal squamous cell carcinoma (SCC)have shown certain chromosomal regions with recurring alterations. But studies of sequential molecular alterations and genetic progression model of laryngeal SCC have not been clearly defined. To identify the chromosomal alterations associated with the carcinogenesis of laryngeal SCC, we analyzed genomic DNA from microdissected squamous metaplasia, squamous dysplasia, invasive SCC, and metastatic carcinoma samples from 22 laryngeal SCC patients for loss of heterozygosity (LOH) at microsatellite loci. Ten microsatellite markers on chromosome 3p, 8p, 9p, and 17p were used. LOH at 9p21 was observed in the all stages including squamous metaplasia, squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 17p13.1, 3p25 and 3p14.2 was observed from the squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 8p21.3-p22 was observed mainly from the invasive SCC and metastatic carcinoma. The results suggest that 9p21 in the early event, 17p13.1, 3p25 and 3p14.2 in the intermediate event and 8p21.3-p22 in the late event may be involved in the laryngeal carcinogenesis.