Detection of human papillomavirus and relevant tumor suppressors and oncoproteins in laryngeal tumors

Analysis of the prognostic significance and potential mechanisms of lncRNAs related to m6A methylation in laryngeal cancer

Objective to investigate the prognostic significance and potential mechanism analysis of m6A methylation-associated lncRNAs in laryngeal cancer. Methods based on the expression of m6A-associated lncRNAs, the samples were divided into two clusters and least absolute value and selection operator (LASSO) regression analysis was performed to build and validate prognostic models. In addition, the relationships between risk scores, clusters, arginine synthase (SMS), tumor microenvironment, clinicopathological features, immune infiltration, immune checkpoints, and tumor mutation burden were analyzed. Finally, the relationship between SMS and m6A-associated IncRNAs was analyzed and SMS-associated pathways were enriched by gene set enrichment analysis (GSEA). Results a total of 95 lncRNAs were associated with the expression of 22 m6A methylation regulators in laryngeal cancer, 14 of which were prognostic lncRNAs. These lncRNAs were divided into two clusters and evaluated. Clinicopathological features did not show significant differences. However, the two clusters differed significantly in terms of naive B cells, memory B cells, naive CD4 T cells, T helper cells and immune score. lASSO regression analysis showed that risk score was a significant predictor of progression-free survival. Conclusion low expression of m6A-related lncRNAs involved in laryngeal cancer development in laryngeal cancer tissues can be used as an indicator to diagnose patients with laryngeal cancer, reduce patient prognosis, be an independent risk factor affecting patient prognosis and be able to assess patient prognosis.

Expanded Basal Compartment and Disrupted Barrier in Vocal Fold Epithelium Infected with Mouse Papillomavirus MmuPV1

Laryngeal infection with low-risk human papillomaviruses can cause recurrent respiratory papillomatosis (RRP), a disease with severe effects on vocal fold epithelium resulting in impaired voice function and communication. RRP research has been stymied by limited preclinical models. We recently reported a murine model of laryngeal MmuPV1 infection and disease in immunodeficient mice. In the current study, we compare quantitative and qualitative measures of epithelial proliferation, apoptosis, differentiation, and barrier between mice with MmuPV1-induced disease of the larynx and surrounding tissues and equal numbers of uninfected controls. Findings supported our hypothesis that laryngeal MmuPV1 infection recapitulates many features of RRP. Like RRP, MmuPV1 increased proliferation in infected vocal fold epithelium, expanded the basal compartment of cells, decreased differentiated cells, and altered cell–cell junctions and basement membrane. Effects of MmuPV1 on apoptosis were equivocal, as with RRP. Barrier markers resembled human neoplastic disease in severe MmuPV1-induced disease. We conclude that MmuPV1 infection of the mouse larynx provides a useful, if imperfect, preclinical model for RRP that will facilitate further study and treatment development for this intractable and devastating disease.

Association between HPV infection and prostate cancer in a Mexican population

The aim of this study was to evaluate the association between prostate cancer (PCa) and Human papillomavirus (HPV) infection in the Mexican population. We studied 356 paraffin-embedded tissues from unrelated Mexican men with PCa or benign prostatic hyperplasia (BPH), with the latter serving as control. HPV detection was performed by polymerase chain reaction (PCR) using universal primers, and viral genotypes were detected using sequencing or multiplex PCR. Light microscopy analyses enabled the identification of koilocytes in samples subsequently analyzed for HPV detection by in situ PCR and for p16-INK4A expression by immunohistochemistry. The results showed that high risk- (HR) HPVs were detected in 37/189 (19.6%) PCa specimens compared to 16/167 (9.6%) of BHP specimens (odds ratio 2.3; 95% CI= 1.2 to 4.3; p=0.01). These data suggest HR-HPV may play a role in PCa. HPV 52 and 58 were the most frequent genotypes (33 and 17%, respectively) detected in the population studied. Koilocytes were detected in all in situ PCR-HPV-positive samples, representing a pathognomonic feature of infection, and we observed the overexpression of p16-INK4A in HPV-positive samples compared to HPV-negative samples, indirectly suggesting the presence of HR-HPV E7 oncoprotein. These results suggest that HPV infection plays an important role in prostate cancer development.

Low risk HPV-6E6 induces apoptosis in bone marrow-derived dendritic cells

The present study assessed the subcellular localization and apoptotic potential of low-risk human papilloma virus 6E6 (HPV-6E6), expressed in bone marrow-derived dendritic cells (DCs). DCs were obtained from C57BL/6 mice and transfected with a pGFP-6E6 plasmid. The subcellular localization of E6 was determined by tracing green fluorescent protein (GFP) using fluorescence microscopy. Apoptosis was assessed by staining nuclei with DAPI and performing an apoptosis-based flow cytometry assay. The co-localization of E6 and p53 was also investigated using confocal microscopy. In addition, the expression of apoptosis-associated proteins was analyzed using immunoblotting. The results of the present study demonstrated that low-risk HPV-6E6 is predominantly localized in the cytoplasm of DCs. Furthermore, p53 was upregulated in DCs transfected with pGFP-6E6 and co-localized with GFP-6E6 in the cytoplasm. DCs transfected with a control pGFP plasmid did not undergo apoptosis, whereas cells transfected with pGFP-6E6 did, as indicated by the presence of cell debris and condensation of the nuclei. Furthermore, the expression of apoptosis-associated proteins, including p53, BCL2 associated X apoptosis regulator (Bax), BCL2 homologous antagonist/killer (Bak) and cytochrome c, were significantly higher in DCs expressing low-risk E6 than in control cells. Therefore, the current study demonstrated that low-risk HPV-6E6 is predominantly located in the cytoplasm of DCs and induces apoptosis. This may be an important mechanism that explains why low-risk HPV is unable to induce malignant transformation.

LG-362B targets PML-RARα and blocks ATRA resistance of acute promyelocytic leukemia

Acute promyelocytic leukemia (APL) is a M3 subtype of acute myeloid leukemia (AML). Promyelocytic leukemia (PML)-retinoic acid receptor α (RARα) translocation generally occurs in APL patients and makes APL unique both for diagnosis and treatment. However, some conventional drugs like all-transretinoic acid (ATRA) and arsenic trioxide (ATO), as the preferred ones for APL therapy, induce irreversible resistance and responsible for clinical failure of complete remission. Herein, we screened a library of novel chemical compounds with structural diversity and discovered a novel synthetic small compound, named LG-362B, specifically inhibited the proliferation of APL and induced apoptosis. Notably, the differentiation arrest was also relieved by LG-362B in cultured APL cells and APL mouse models. Moreover, LG-362B overcame the ATRA resistance on cellular differentiation and transplantable APL mice. These positive effects were driven by caspases-mediated degradation of PML-RARα when treated with LG-362B, making it specific to APL and reasonable for ATRA resistance relief. We propose that LG-362B would be a potential candidate agent for the treatment of the relapsed APL with ATRA resistance in the future.

Identification of genes associated with laryngeal squamous cell carcinoma samples based on bioinformatic analysis

The present study aimed to investigate the differentially expressed genes (DEGs) between laryngeal squamous cell carcinoma (LSCC) samples and non‑neoplastic laryngeal squamous cell samples, and the underlying biological mechanism. Gene expression profile data of GSE51985 and GSE10288 were obtained from the Gene Expression Omnibus database. The DEGs between the LSCC and normal samples were identified using the rowtest function in the genefilter package. Hierarchical clustering for DEGs was performed to confirm the distinction between the identified DEGs, and Gene Ontology term and pathway enrichment analyses were performed to determine the underlying function of the DEGs. In addition, protein‑protein interaction networks were established to investigate the interactive mechanism of the DEGs. A total of 1,288 upregulated genes and 317 downregulated genes were identified between the LSCC samples and non‑neoplastic LSC samples in the GSE51985 dataset, and five upregulated and 26 downregulated genes were identified in the samples from the GSE10288 dataset. The DEGs were clearly distinguished between the LSCC sample and the non‑neoplastic LSCC sample by hierarchical clustering. The upregulated genes were predominantly involved in the cell cycle, cell division or focal adhesion, and the 295 upregulated genes formed 374 protein interaction pairs in interaction network analysis. The results revealed that the genes involved in the cell cycle, in cell division or in focal adhesion were associated with the development and progression of LSCC.

Chromosome instability predicts progression of premalignant lesions of the larynx

The histopathology of premalignant laryngeal lesions does not provide reliable information on the risk of malignant transformation, hence we examined new molecular markers which can easily be implemented in clinical practice. Dual-target fluorescence in situ hybridisation (FISH) for chromosome 1 and 7 centromeres was performed on tissue sections of laryngeal premalignancies in 69 patients. Chromosome instability was indicated by numerical imbalances and/or polysomy for chromosomes 1 and 7. Additionally, immunostainings for p53, Cyclin D1 and (p)FADD expression were evaluated. Malignant progression was recorded. Eighteen patients with carcinoma in situ (CIS) were treated after diagnosis and excluded from follow-up. Chromosome instability was strongly associated with a high risk of malignant transformation, especially in lower grade lesions (hyperplasia, mild and moderate dysplasia; odds ratio = 8.4, p = 0.004). Patients with lesions containing chromosome instability showed a significantly worse 5-year progression-free survival than those with premalignancies without chromosome instability (p = 0.002). Neither histopathology nor the protein markers predicted progression in univariate analysis, although histopathological diagnosis, p53 and FADD contributed positively to chromosome instability in multivariate analysis. Chromosome instability is associated with malignant progression of laryngeal premalignancies, especially in lower grade lesions. These results may contribute to better risk counselling, provided that they can be validated in a larger patient set.

Oxymatrine downregulates HPV16E7 expression and inhibits cell proliferation in laryngeal squamous cell carcinoma Hep-2 cells in vitro

Objective. To investigate the possible mechanisms of oxymatrine's role in anti laryngeal squamous cell carcinoma. Methods. We examined the effects of oxymatrine on the proliferation, cell cycle phase distribution, apoptosis, and the protein and mRNA expression levels of HPV16E7 gene in laryngeal carcinoma Hep-2 cells in vitro. The HPV16E7 siRNA inhibition was also done to confirm the effect of downregulating HPV16E7 on the proliferation in Hep-2 cells. Results. Oxymatrine significantly inhibited the growth and proliferation of Hep-2 cells in a dose-dependence and time-dependence manner. Oxymatrine blocked Hep-2 cells in G0/G1 phase, resulting in an obvious accumulation of G0/G1 phase cells while decreasing S phase cells. Oxymatrine induced apoptosis of Hep-2 cells, whose apoptotic rate amounted to about 42% after treatment with 7 mg/mL oxymatrine for 72 h. Oxymatrine also downregulated the expression of HPV16E7 gene, as determined by the western blotting and reverse transcription-polymerase chain reaction analysis. Knockdown of HPV16E7 effectively inhibited the proliferation of Hep-2 cells. Conclusions. Oxymatrine inhibits the proliferation and induces apoptosis of laryngeal carcinoma Hep-2 cells, which might be mediated by a significant cell cycle arrest in G0/G1 phase and downregulation of HPV16E7 gene. Oxymatrine is considered to be a likely preventive and curative candidate for laryngeal cancer.

Investigation of biomarker in laryngeal carcinomas

BACKGROUND

The aim of the study is to determine whether there is a role of podoplanin and glutathione S-transferases T1 (GST-T1) expression in laryngeal squamous cell carcinoma.

METHODS

In this study, 33 patients were enrolled and gene expression analysis was performed by qRT-PCR. The podoplanin and GST-T1 expression patterns were analyzed to determine their correlation with clinicopathologic parameters of laryngeal cancer.

RESULTS

Of all included patients, 20 had supraglottic, and 13 had glottic laryngeal cancer. Increased expression of podoplanin was found in seven (35%) supraglottic tumor tissues and seven (53.8%) glottic tumor tissues, but GST-T1 expression was not detected.

CONCLUSION

Podoplanin expression did not show any prediction for tumor differentiation, regional metastasis, thyroid cartilage invasion, lymphatic vessel invasion, or tumor differentiation for laryngeal cancer, and also there were no significant differences in podoplanin expression between glottic and supraglottic regions, but extracapsullar extension is almost statistically significance (P = 0.05).

In situ molecular identification of the influenza A (H1N1) 2009 Neuraminidase in patients with severe and fatal infections during a pandemic in Mexico City

Background

In April 2009, public health surveillance detected an increased number of influenza-like illnesses in Mexico City’s hospitals. The etiological agent was subsequently determined to be a spread of a worldwide novel influenza A (H1N1) triple reassortant. The purpose of the present study was to demonstrate that molecular detection of pandemic influenza A (H1N1) 2009 strains is possible in archival material such as paraffin-embedded lung samples.

Methods

In order to detect A (H1N1) virus sequences in archived biological samples, eight paraffin-embedded lung samples from patients who died of pneumonia and respiratory failure were tested for influenza A (H1N1) Neuraminidase (NA) RNA using in situ RT-PCR.

Results

We detected NA transcripts in 100% of the previously diagnosed A (H1N1)-positive samples as a cytoplasmic signal. No expression was detected by in situ RT-PCR in two Influenza-like Illness A (H1N1)-negative patients using standard protocols nor in a non-related cervical cell line. In situ relative transcription levels correlated with those obtained when in vitro RT-PCR assays were performed. Partial sequences of the NA gene from A (H1N1)-positive patients were obtained by the in situ RT-PCR-sequencing method. Sequence analysis showed 98% similarity with influenza viruses reported previously in other places.

Conclusions

We have successfully amplified specific influenza A (H1N1) NA sequences using stored clinical material; results suggest that this strategy could be useful when clinical RNA samples are quantity limited, or when poor quality is obtained. Here, we provide a very sensitive method that specifically detects the neuraminidase viral RNA in lung samples from patients who died from pneumonia caused by Influenza A (H1N1) outbreak in Mexico City.

Human papillomavirus in non-oropharyngeal head and neck cancers: a systematic literature review

Perhaps one of the most important developments in head and neck oncology of the past decade is the demonstration that patients with human papillomavirus (HPV)-mediated oropharyngeal cancers have significantly improved outcomes, compared to HPV-negative counterpart patients. This has become the basis for clinical trials investigating the impact on "treatment deintensification" for patients with HPV-mediated oropharyngeal cancers. Unfortunately, the significance of HPV in non-oropharyngeal head and neck cancers is much less certain. Our goal is to systematically review the published data regarding the role HPV in carcinomas of the oral cavity, larynx, sinonasal tract and nasopharynx with respect to HPV detection frequency, viral activity, and association with outcome. We also present preliminary data on HPV16/18 transcriptional status in oral cavity carcinomas, as well as salivary gland neoplasia, as determined by nested reverse transcription PCR for HPV E6/E7 RNA. The weighted prevalence (WP) of HPV DNA detection in 4,195 oral cavity cancer patients is 20.2 %, (95 % CI 16.0 %, 25.2 %). HPV16 is the most common type detected. Importantly, no data currently demonstrates a significant association between the presence of HPV DNA and improved outcome. The WP of HPV DNA in 1,712 laryngeal cancer patients is 23.6 %, (95 % CI 18.7 %, 29.3 %). Similarly, no association has yet been demonstrated between HPV DNA status and outcome. The WP of HPV DNA detection in 120 sinonasal cancer patients is 29.6 % (95 % CI 17.8 %, 44.9 %), and in 154 nasopharyngeal carcinoma patients is 31.1 %, (95 % CI 20.3 %, 44.5 %). Recent preliminary data also suggests an association between HPV and certain salivary gland neoplasms. The clinical significance of these findings is unclear. The published data strongly support the need for studies on patients with oral and laryngeal carcinomas that will be powered to find any differences in clinical outcome with respect to HR-HPV and p16 overexpression.

Epidemiology of human papillomavirus-related head and neck cancer

Human papillomavirus (HPV) is now recognized to cause a subset of head and neck squamous cell carcinomas (HNSCC). Although excessive tobacco and alcohol use continue to be important risk factors for HNSCC, epidemiologic studies suggest that more than 25% of HNSCC are now caused by HPV. The incidence of HPV-related HNSCC is increasing, highlighting the need to understand the oral HPV infections causing these cancers. This article reviews the evidence for a causal association between HPV and HNSCC, examines the changing epidemiologic trends of HNSCC, and discusses what is currently known about oral HPV infection, natural history, and transmission.

Stem cell-related proteins C-KIT, C-MYC and BMI-1 in juvenile nasopharyngeal angiofibroma--do they have a role?

Juvenile nasopharyngeal angiofibroma (JNA) is a highly vascular tumour, occurring almost exclusively in adolescent males. Histogenesis of JNA remains unclear, two optional theories proposing either fibrous or vascular tissue as the tissue of origin. Stem cell-related proteins have been discussed to possibly participate in the growth of these tumours. In our study, we reviewed retrospective clinicopathological data of 26 JNA patients. By immunohistochemistry, we investigated the cellular distribution and expression levels of stem cell-related proteins C-KIT, C-MYC and BMI-1 and their correlation with cell and vessel density of the tumour. Contrary to earlier reports, we detected C-KIT expression in addition to stromal cells also in endothelial cells. The C-KIT expression was more dominant in slit vessels than large vessels. A significant correlation was found between endothelial immunoexpression of C-KIT and cellular density of the tumour. C-MYC and BMI-1 expression was detected in stromal cells only. Due to our finding of C-KIT expression in both stromal and endothelial cells and the strong correlation between the endothelial C-KIT expression and cellular density, we suggest that, besides the stromal tissue, the vascular component might take part in the neoplastic growth of JNA.

Entamoeba histolytica calreticulin: an endoplasmic reticulum protein expressed by trophozoites into experimentally induced amoebic liver abscesses

Entamoeba histolytica calreticulin (EhCRT) is remarkably immunogenic in humans (90-100% of invasive amoebiasis patients). Nevertheless, the study of calreticulin in this protozoan is still in its early stages. The exact location, biological functions, and its role in pathogenesis are yet to be fully understood. The aim of the present work is to determine the location of EhCRT in virulent trophozoites in vivo and the expression of the Ehcrt gene during the development of experimentally induced amoebic liver abscesses (ALA) in hamsters. Antibodies against recombinant EhCRT were used for the immunolocalization of EhCRT in trophozoites through confocal microscopy; immunohistochemical assays were also performed on tissue sections of ALAs at different times after intrahepatic inoculation. The expression of the Ehcrt gene during the development of ALA was estimated through both in situ RT-PCR and real-time RT-PCR. Confocal assays of virulent trophozoites showed a distribution of EhCRT in the cytoplasmic vesicles of different sizes. Apparently, EhCRT is not exported into the hepatic tissue. Real-time RT-PCR demonstrated an over-expression of the Ehcrt gene at 30 min after trophozoite inoculation, reaching a peak at 1-2 h; thereafter, the expression fell sharply to its original levels. These results demonstrate for the first time in an in vivo model of ALA, the expression of Ehcrt gene in E. histolytica trophozoites and add evidence that support CRT as a resident protein of the ER in E. histolytica species. The in vivo experiments suggest that CRT may play an important role during the early stages of the host-parasite relationship, when the parasite is adapting to a new environment, although the protein seems to be constitutively synthesized. Moreover, trophozoites apparently do not export EhCRT into the hepatic tissue in ALA.

14-3-3epsilon contributes to tumour suppression in laryngeal carcinoma by affecting apoptosis and invasion

Background

14-3-3epsilon regulates a wide range of biological processes, including cell cycle control, proliferation, and apoptosis, and plays a significant role in neurogenesis and the formation of malignant tumours. However, the exact function and regulatory mechanism of 14-3-3epsilon in carcinogenesis have not been elucidated.

Methods

The expression of 14-3-3epsilon was assessed by RT-PCR and western blotting. The invasiveness and viability of Hep-2 cells were determined by the transwell migration assay and MTT assay, respectively. Cell cycle and apoptosis of Hep-2 cells were detected by flow cytometry.

Results

The mRNA and protein expression of 14-3-3epsilon in larynx squamous cell carcinoma (LSCC) tissues were significantly lower than those in clear surgical margin tissues. Statistical analysis showed that the 14-3-3epsilon protein level in metastatic lymph nodes was lower than that in paired tumour tissues. In addition, the protein level of 14-3-3epsilon in stage III or IV tumours was significantly lower than that in stage I or II tumours. Compared with control Hep-2 cells, the percentages of viable cells in the 14-3-3epsilon-GFP and negative control GFP groups were 36.68 ± 14.09% and 71.68 ± 12.10%, respectively. The proportions of S phase were 22.47 ± 3.36%, 28.17 ± 3.97% and 46.15 ± 6.82%, and the apoptotic sub-G1 populations were 1.23 ± 1.02%, 2.92 ± 1.59% and 13.72 ± 3.89% in the control, negative control GFP and 14-3-3epsilon-GFP groups, respectively. The percentages of the apoptotic cells were 0.84 ± 0.25%, 1.08 ± 0.24% and 2.93 ± 0.13% in the control, negative control GFP and 14-3-3epsilon-GFP groups, respectively. The numbers of cells that penetrated the filter membrane in the control, negative control GFP and 14-3-3epsilon-GFP groups were 20.65 ± 1.94, 17.63 ± 1.04 and 9.1 ± 0.24, respectively, indicating significant differences among the different groups.

Conclusions

Decreased expression of 14-3-3epsilon in LSCC tissues contributes to the initiation and progression of LSCC. 14-3-3epsilon can promote apoptosis and inhibit the invasiveness of LSCC.

Immunological responses against human papilloma virus and human papilloma virus induced laryngeal cancer

Objective:

This study aimed to clarify the local immune status in the larynx in the presence of infection or carcinogenesis associated with human papilloma virus.

Methods:

Cytological samples (for human papilloma virus detection) and laryngeal secretions (for immunoglobulin assessment) were obtained from 31 patients with laryngeal disease, during microscopic laryngeal surgery. On histological examination, 12 patients had squamous cell carcinoma, four had laryngeal papilloma and 15 had other benign laryngeal disease. Cytological samples were tested for human papilloma virus DNA using the Hybrid Capture 2 assay.

Results:

High risk human papilloma virus DNA was detected in 25 per cent of patients (three of 12) with laryngeal cancer. Low risk human papilloma virus DNA was detected only in three laryngeal papilloma patients. The mean laryngeal secretion concentrations of immunoglobulins M, G and A and secretory immunoglobulin A in human papilloma virus DNA positive patients were more than twice those in human papilloma virus DNA negative patients. A statistically significant difference was observed between the secretory immunoglobulin A concentrations in the two groups. Patients with laryngeal cancer had higher laryngeal secretion concentrations of each immunoglobulin type, compared with patients with benign laryngeal disease. The study assessed the mean laryngeal secretion concentrations of each immunoglobulin type in the 12 laryngeal cancer patients, comparing human papilloma virus DNA positive patients (n = 3) and human papilloma virus DNA negative patients (n = 9); the mean concentrations of immunoglobulins M, G and A and secretory immunoglobulin A tended to be greater in human papilloma virus DNA positive cancer patients, compared with human papilloma virus DNA negative cancer patients.

Conclusion:

These results suggest that the local laryngeal immune response is activated by infection or carcinogenesis due to human papilloma virus. The findings strongly suggest that secretory IgA has inhibitory activity against infection or carcinogenesis associated with human papilloma virus in the larynx.

Human papillomavirus is not associated with colorectal cancer in a large international study

OBJECTIVE OF THE STUDY

Recent publications have reported an association between colon cancer and human papillomaviruses (HPV), suggesting that HPV infection of the colonic mucosa may contribute to the development of colorectal cancer.

METHODS

The GP5+/GP6+ PCR reverse line blot method was used for detection of 37 types of human papillomavirus (HPV) in DNA from paraffin-embedded or frozen tissues from patients with colorectal cancer (n = 279) and normal adjacent tissue (n = 30) in three different study populations, including samples from the United States (n = 73), Israel (n = 106) and Spain (n = 100). Additionally, SPF10 PCR was run on all samples (n = 279) and the Innogenetics INNO-LiPA assay was performed on a subset of samples (n = 15).

RESULTS

All samples were negative for all types of HPV using both the GP5+/GP6+ PCR reverse line blot method and the SPF10 INNO-LiPA method.

CONCLUSIONS

We conclude that HPV types associated with malignant transformation do not meaningfully contribute to adenocarcinoma of the colon.

Regulation of the cell cycle gene, BTG2, by miR-21 in human laryngeal carcinoma

MicroRNAs are short regulatory RNAs that negatively modulate gene expression at the post-transcriptional level, and are deeply involved in the pathogenesis of several types of cancers. To investigate whether specific miRNAs and their target genes participate in the molecular pathogenesis of laryngeal carcinoma, oligonucleotide microarrays were used to assess the differential expression profiles of microRNAs and mRNAs in laryngeal carcinoma tissues compared with normal tissues. The oncogenic miRNA, microRNA-21 (miR-21), was found to be upregulated in laryngeal carcinoma tissues. Knockdown of miR-21 by specific antisense oligonucleotides inhibited the proliferation potential of HEp-2 cells, whereas overexpression of miR-21 elevated growth activity of the cells, as detected by the colony formation assay. The cell number reduction caused by miR-21 inhibition was due to the loss of control of the G1-S phase transition, instead of a noticeable increase in apoptosis. Subsequently, a new target gene of miR-21, BTG2, was found to be downregulated in laryngeal carcinoma tissues. BTG2 is known to act as a pan-cell cycle regulator and tumor suppressor. These findings indicate that aberrant expression of miR-21 may contribute to the malignant phenotype of laryngeal carcinoma by maintaining a low level of BTG2. The identification of the oncogenic miR-21 and its target gene, BTG2, in laryngeal carcinoma is potentially valuable for cancer diagnosis and therapy.

Induction of focal epithelial hyperplasia in tongue of young bk6-E6/E7 HPV16 transgenic mice

Squamous cell carcinoma (SCC) of the oral cavity is one of the most common neoplasms in the world. During the past 2 decades, the role of high-risk human papilloma virus (HR-HPV) has been studied and the data supporting HPV as a one of the causative agents in the development and progression of a sub-set of head and neck squamous cell carcinomas (HNSCC) has accumulated. In order to investigate the role of HR-HPV oncogene expression in early epithelial alterations in vivo, we produced transgenic mice expressing HPV16 early region genes from the promoter of the bovine keratin 6 gene (Tg[bK6-E6/E7]). In this article, we demonstrate that E6/E7 transgene was abundantly expressed and cellular proliferation was increased in the middle tongue epithelia of transgenic mice, and that in the same region young (27 weeks old) Tg[bK6-E6/E7] mice spontaneously developed histological alterations, mainly focal epithelial hyperplasia (FEH).

Laryngeal squamous cell carcinoma in a 13 year-old child associated with human papillomaviruses 16 and 18: a case report and review of the literature

Squamous cell carcinoma (SCC) of the larynx is extremely rare in adolescents and typically has an aggressive nature. The mechanism of laryngeal oncogenesis is complex and little is known about the role that human papillomavirus (HPV) plays in SCC in adolescents. We report a case of invasive laryngeal SCC that co-expressed HPV DNA subtypes 16 and 18 in a 13 year-old boy. Detection of HPV DNA types 6, 11, 16, 18, 31, 33, and 51 was performed by in situ hybridization, with confirmation by polymerase chain reaction. Immunohistochemical staining with p16 and HPV 16/18 revealed diffusely positive staining in the tumor cells. Coinfection by HPV DNA types 16 and 18 has not been previously reported, but our case suggests that HPV is a risk factor in developing laryngeal SCC in children and adolescents. Future studies evaluating HPV in the pathogenesis of these lesions is recommended to determine its prognostic significance.

Integration of human papilloma virus type 26 in laryngeal cancer of a child

Squamous cell carcinoma (SCC) in larynx is rare with children and adolescents. Usually larynx cancer is common with male smokers in the 7th decade. Among patients with no history of tobacco and/or alcohol consumption several factors have can play a role in the outbreak of laryngeal cancer: such as individual predisposition, radiation, gastroesophageal reflux, viral infection, dietary factors and environmental influences. In literature only few cases of laryngeal cancer with children are reported. Recent studies show that the most frequent laryngeal malignancy is the embryonal rhabdomyosarcoma. Besides the recurrent respiratory papillomatosis (RRP) based on an infection with human papilloma virus (HPV) types 6 and 11 (low risk) and types 16 and 18 (high risk) is known for a possible malignant transformation towards a SCC. HPV type 26 is only reported as low risk type HPV associated with cervical cancer. Final diagnosis often takes a long time. Initial symptoms such as hoarseness, cough or shortness of breath are often referred to more typical pediatric diseases or laryngeal development.