Comprehensive analysis of the immune implication of EPHX4 gene in laryngeal squamous cell carcinoma.

OBJECTIVES: The role of Epoxide Hydrolase-4 (EPHX4), a member of epoxide hydrolase family, has not been investigated in cancer. The purpose of this article is to explore the application value of EPHX4 in laryngeal cancer and its relationship with immune infiltration. METHODS: We observed that EPHX4 expression and its survival assays in laryngeal cancer specimens based on The Cancer Genome Atlas (TCGA) cohorts. We also analyzed the correlation between immune cell infiltration levels and EPHX4 gene copy number in laryngeal cancer. Finally, we conducted in vitro assay to evaluate the functions of EPHX4 in laryngeal cancer cell line. RESULTS: EPHX4 is highly expressed in laryngeal cancer specimens and has a poor prognosis. EPHX4 related immune cell analysis showed that it participated in NK Natural killer cell mediated cytotoxicity. Finally, Cell experiments indicate that EPHX4 could promote laryngeal cancer cell line proliferation, colony formation and invasion. CONCLUSIONS: Our research results suggest that EPHX4 may be a potential immunotherapy target for laryngeal cancer. The nominated immune signature is a helpful and promising prognostic indicator in laryngeal cancer. LEVELS OF EVIDENCE: Level 3.

Effective prognostic risk model with cuproptosis-related genes in laryngeal cancer.

OBJECTIVE: Laryngeal cancer, characterized by high recurrence rates and a lack of effective biomarkers, has been associated with cuproptosis, a regulated cell death process linked to cancer progression. In this study, we aimed to explore the roles of cuproptosis-related genes in laryngeal cancer and their potential as prognostic markers and therapeutic targets. METHODS: We collected comprehensive data from The Cancer Genome Atlas and Gene Expression Omnibus databases, including gene expression profiles and clinical data of laryngeal cancer patients. Using clustering and gene analysis, we identified cuproptosis-related genes with prognostic significance. A risk model was constructed based on these genes, categorizing patients into high- and low-risk groups for outcome comparison. Univariate and multivariate analyses were conducted to identify independent prognostic factors, which were then incorporated into a nomogram. Gene Set Enrichment Analysis was employed to explore pathways distinguishing high- and low-risk groups. RESULTS: Our risk model, based on four genes, including transmembrane 2, dishevelled binding antagonist of ß-catenin 1, stathmin 2, and G protein-coupled receptor 173, revealed significant differences in patient outcomes between high- and low-risk groups. Independent prognostic factors were identified and integrated into a nomogram, providing a valuable tool for prognostic prediction. Gene Set Enrichment Analysis uncovered up-regulated pathways specifically associated with high-risk patient samples. CONCLUSION: This study highlights the potential of cuproptosis-related genes as valuable prognostic markers and promising therapeutic targets in the context of laryngeal cancer. This research sheds light on new avenues for understanding and managing this challenging disease. LEVEL OF EVIDENCE: Level 4.

MicroRNA-150-5p inhibits the proliferation and invasion of human larynx epidermiod cancer cells though regulating peptidyl-prolyl cis/trans isomerase.

OBJECTIVE: This study aimed to investigate the molecular mechanism of miR-150-5p regulating the malignant biological behavior of Human Epidermoid cancer cell (HEp-2) by targeting peptidyl-prolyl cis/trans isomerase NIMA-Interacting-1 (PIN1). METHODS: Firstly, qRT-PCR and Western blot were adopted to detect the expression levels of miR-150-5p and PIN1 in cancer tissue and paracancerous tissues of patients with LSCC, and those in human bronchial epithelial cells (16 HBE) and HEp-2. Next, the targeted relationship between miR-150-5p and PIN1 was assessed by bioinformatics website and dual-luciferase reporter assay, followed by their correlation analysis. Besides, after interfering with miR-150-5p or PIN1 expression in HEp-2 cells, CCK-8, cell colony formation assay, and transwell assay were utilized to detect the proliferation, viability, and invasion of cells, respectively. Subsequently, the protein levels of MMP-2, MMP-9, and EMT-related proteins in HEp-2 cells were checked by Western blot. RESULTS: Expression of miR-150-5p was down-regulated in LSCC tissues and HEp-2 cells. Moreover, miR-150-5p suppressed proliferation and invasion of HEp-2 cells, affected protein expression related to MMP and EMT, thereby inhibiting development of cancer. The expression of PIN1 was significantly increased in cancer tissues and HEp-2 cells, and there was a targeted relationship and negative correlation between miR-150-5p and PIN1 in cancer tissue. However, overexpression of PIN1 could reverse the effect of miR-150-5p on the proliferation and invasion of HEp-2 cells. CONCLUSION: In a nutshell, there is a targeted relationship between PIN1 and miR-150-5p. Besides, miR-150-5p can inhibit the proliferation and invasion of HEp-2 cells by regulating the expression of PIN1.

MicroRNA-375 inhibits laryngeal squamous cell carcinoma progression via targeting CST1.

OBJECTIVE: This study aims to explore the effect and mechanism of miR-375 in Laryngeal Squamous Cell Carcinoma (LSCC) cell progression. METHODS: LSCC cells (LSC-1 and TU177) were transfected with miR-375-mimic, miR-375-inhibitor or miR-375-mimic+oe-CST1. The expression of miR-375, CST1, MMP-2, and MMP-9 was measured. The effect of miR-375-mimic, miR-375-inhibitor or miR-375-mimic+oe-CST1 on cell biological functions, including cell proliferation, migration, invasion, and apoptosis, was also assessed. The potential relationship between CST1 and miR-375 was predicted by Jefferson software and validated by dual luciferase reporter gene assay. RESULTS: Downregulated miR-375 expression was found in LSCC cells. Overexpression of miR-375 inhibited the viability and migration and promoted apoptosis of LSCC cells. Jefferson database and dual luciferase reporter gene assay confirmed that miR-375 directly targeted CST1. Overexpression of CST1 could reverse the anti-cancer effect of miR-375 overexpression in LSCC cells. CONCLUSION: Collected evidence showed that miR-375/CST1 axis was implicated in LSCC progression. LEVEL OF EVIDENCE: Level 3.

A novel tumor suppressor CECR2 down regulation links glutamine metabolism contributes tumor growth in laryngeal squamous cell carcinoma.

PURPOSE: Glutamine plays an important role in tumor metabolism and progression. This research aimed to find out how Gln exert their effects on laryngeal squamous cell carcinoma (LSCC). METHODS: Cell proliferation was measured by CCK8 and EdU assay, mitochondrial bioenergetic activity was measured by mitochondrial stress tests. Gene expression profiling was revealed by RNA sequencing and validated by RT-qPCR. In LSCC patients, protein expression in tumor and adjacent tissues was examined and scored by IHC staining. RNAi was performed by stably expressed shRNA in TU177 cells. In vivo tumor growth analysis was performed using a nude mouse tumorigenicity model. RESULTS: Gln deprivation suppressed TU177 cell proliferation, which was restored by αKG supplementation. By transcriptomic analysis, we identified CECR2, which encodes a histone acetyl-lysine reader, as the downstream target gene for Gln and αKG. In LSCC patients, the expression of CECR2 in tumors was lower than adjacent tissues. Furthermore, deficiency of CECR2 promoted tumor cell growth both in vitro and in vivo, suggesting it has tumor suppressor effects. Besides, cell proliferation inhibited by Gln withdrawal could be restored by CECR2 depletion, and the proliferation boosted by αKG supplementation could be magnified either, suggested that CECR2 feedback suppressed Gln and αKG's effect on tumor growth. Transcriptomic profiling revealed CECR2 regulated the expression of a series of genes involved in tumor progression. CONCLUSION: We confirmed the Gln-αKG-CECR2 axis contributes to tumor growth in LSCC. This finding provided a potential therapeutic opportunity for the use of associated metabolites as a potential treatment for LSCC.

Knockdown of long non-coding RNA RP11-297P16.3 inhibits the migration and invasion of laryngeal squamous carcinoma cells.

PURPOSE: Laryngeal cancer has a poor prognosis when progressing to an advanced stage with limited treatment options. Therefore, understanding the underlying mechanisms is important to identify novel treatment targets. Long non-coding RNAs (lncRNAs) have been shown to play oncogenic roles in cancer, including in laryngeal cancer. We previously discovered that the lncRNA RP11-297P16.3 is overexpressed in laryngeal squamous cell carcinoma (LSCC) based on RNA-sequencing data. Therefore, the aim of the present study was to investigate the effects of knockdown of RP11-297P16.3 on the migration and invasion of LSCC cells, and the significance of these effects. METHODS: Six methods were employed to assess the function of RP11-297P16.3 including gene silencing, RT-PCR, the 5-Ethynyl-20-deoxyuridine (EdU) staining assay, Scratch wound-healing assay, transwell assay, and Western blot. RESULTS: The results show that the expression of RP11-297P16.3 in the si-lncRNA group was significantly decreased compared with those in the BC (blank control) and NC (negative control) groups. Moreover, knockdown of RP11-297P16.3 significantly inhibited the migration and invasion of LSCC cells but had no effect on cell proliferation. The protein expression of N-cadherin and vimentin was notably decreased after RP11-297P16.3 knockdown; whereas, the protein expression of cadherin was significantly increased CONCLUSION: These results suggested that RP11-297P16.3 may inhibit the migration and invasion of LSCC cells by regulating the epithelial-mesenchymal transition process, suggesting that RP11-297P16.3 is a potential new target for treating LSCC.

Genetic polymorphisms as non-modifiable susceptibility factors to laryngeal cancer.

Laryngeal squamous cell carcinoma (LSCC) is a highly disabling disease to the patient, affecting speech, swallowing and respiratory skills. Smoking and alcohol abuse are principal risk factors linked to this disease. Genetic factors can be involved in carcinogenesis by controlling the cell cycle, cell survival, angiogenesis, and invasiveness. Single nucleotide polymorphisms (SNPs) involving specific genes could modulate the risk of LSCC related to known carcinogens by modifying cellular responses, but not all genetic associations are known. In a case-control study, we assess the associations between cyclooxygenase-2 (COX2), epidermal growth factor (EGF), EGF receptor (EGFR), and tumor suppressor P53 SNPs on the risk of LSCC development in the Chilean population. A total of 85 LSCC patients and 95 healthy volunteers were recruited. SNPs genotype were analyzed from genomic DNA by Polymerase Chain Reaction (PCR)-Restriction Fragment Length Polymorphism (RFLP) and associations were estimated by odds ratios (ORs) using unconditional logistic regressions. A significant association between COX2 and TP53 SNP and LSCC risk was found, with an OR = 3.27 for COX2 c.-1329A>G (rs689466) SNP, and an OR = 1.94 for TP53 c.215C>G, Pro72Arg (rs1042522) SNP. These findings suggest that COX2 c.-1329A>G and TP53 c.215C>G (Pro72Arg) SNPs may be risk factors for LSCC. Through this research, we identify two low penetrance genetic variants that may be evaluated as novel biomarkers for this disease, in South American Mestizo populations.

Integrated miRNA and mRNA expression analysis uncovers drug targets in laryngeal squamous cell carcinoma patients.

OBJECTIVES: The current treatment of laryngeal squamous cell carcinoma (LSCC) is based on radical surgery and radiotherapy resulting in high morbidity. Chemoradiotherapy has been used as alternative to organ sparing; however, several advanced cases presented resistance to treatment, which contributes to a high risk of recurrence and mortality. Coding RNAs and miRNAs have potential to be used as biomarkers or targets for cancer therapy. MATERIALS AND METHODS: In this study, 36 LSCC and 5 non-neoplastic control samples were investigated using miRNA and mRNA large-scale expression analysis and a cross-validation was performed using the TCGA database (116 LSCC and 12 surrounding normal tissues). RESULTS: The large-scale profiling revealed the involvement of 28 miRNAs and 817 genes differentially expressed in LSCC. An integrative analysis comprising predicted and experimentally validated miRNA/mRNA interactions (negatively correlated), resulted in 28 miRNAs and 543 mRNAs. Decreased expression of miR-199b was significantly associated with shorter disease-free survival in LSCC (internal and TCGA datasets). The expression levels of selected miRNAs (miR-199b-5p, miR-29c-3p, miR-204-5p, miR-125b-5p and miR-92a-3p) and genes (COL3A1, COL10A1, ERBB4, HMGA2, HLF, TOP2A, MMP3, MMP13, MMP10 and PPP1R3) were confirmed as altered in LSCC by RT-qPCR. Additionally, a drug target prediction analysis revealed drug combinations based on miRNA and mRNA expression, pointing out novel alternatives to optimize the LSCC treatment. CONCLUSION: Collectively, these findings provide new insights in the LSCC transcriptional deregulation and potential drug targets.

CASP9 c.-1339A>G and CASP3 c.-1191A>G polymorphisms alter susceptibility and clinical aspects of head and neck squamous cell carcinoma.

BACKGROUND: Single nucleotide polymorphisms (SNPs) in genes that act in intrinsic apoptosis pathway may modulate cancer susceptibility. This study investigated the roles of CASP9 c.-1339A>G (rs4645978) and CASP3 c.-1191A>G (rs12108497) SNPs on risk and behavior of head and neck (HN) squamous cell carcinoma (SCC). METHODS: DNA of 350 patients with HNSCC and 350 controls was analyzed by polymerase chain reaction method for genotyping. RESULTS: CASP3 c.-1191AG or GG genotype was more common in patients with HNSCC and oral cavity or oropharynx SCC than in controls; carriers of this genotype were under 2.15 and 2.81-fold increased risks of the respective tumors. CASP9 c.-1339AG or GG plus CASP3 c.-1191AG or GG genotypes were associated with oral cavity or oropharynx SCC early onset. CONCLUSION: These findings present, for the first time, preliminary evidence that inherited abnormalities related to CASP9 c.-1339A>G and CASP3 c.-1191A>G SNPs are determinants of HNSCC risk and clinical aspects.

Hydrogen peroxide-induced mitophagy contributes to laryngeal cancer cells survival via the upregulation of FUNDC1.

PURPOSE: The purpose of our study was to investigate an underlying mechanism that hydrogen peroxide-induced mitophagy contributed to laryngeal cancer cells survivals under oxidative stress condition. METHODS: Tumor tissue and serum samples were collected from patients with laryngeal cancer. The Hep2 cell, a human laryngeal carcinoma cell, was used in in vitro experiments. The levels of lipid peroxidation were analyzed by ELISA. Knockdown of FUNDC1 was performed by RNAi. The changes of target proteins were determined by qRT-PCR and western blot. The cells were analyzed for changes in proliferation using cell counting kit-8 and mitophagy by the mitochondrial membrane potential assay and transmission electron microscopy. RESULTS: FUNDC1 in laryngeal cancer tissues were relative to the levels of lipid peroxidation in laryngeal cancer patients, which suggested that FUNDC1 was associated with the status of oxidative stress in the laryngeal cancer patients. Hydrogen peroxide significantly induced the elevation of FUNDC1, a mitophagic factor, in a time- and dose-dependent manner in laryngeal cancer cells, which was dependent on ERK signal activation. Knockdown of FUNDC1 by the siRNA attenuated the survival of laryngeal cancer cells under hydrogen peroxide stimulation. Moreover, the elevated FUNDC1 was required for the occurrence of mitophagy under hydrogen peroxide stimulation, which was identified by transmission electron microscopy, the alterations of mitochondrial permeability transition and the specific mitochondrial protein, hsp60. Inhibition of mitophagy with cyclosporine A could also effectively attenuate the laryngeal cancer cells survival under hydrogen peroxide stimulation. CONCLUSIONS: Hydrogen peroxide upregulated the expression of FUNDC1 through the activation of ERK1/2 signal to trigger a mitophagic response, giving laryngeal cancer cells a befit for survival. These findings suggested that FUNDC1 might be a potential target for the treatment of laryngeal cancer accompanied with high lipid peroxidation status.

HMGA2, but not HMGA1, is overexpressed in human larynx carcinomas.

AIMS: Malignant tumours from the upper aerodigestive tract are grouped collectively in the class of head and neck squamous cell carcinoma (HNSCC). The head and neck tumours were responsible for more than 500 000 cancer cases in 2012, accounting for the sixth highest incidence rate and mortality worldwide among all tumour types. Laryngeal squamous cell carcinoma (LSCC) possesses the second highest incidence rate among all HNSCC. Despite significant advances in surgery and radiotherapy during the last few decades, no treatment has been shown to achieve a satisfactory therapeutic outcome and the mortality rate of LSCC is still high, with a 5-year survival rate of 64%. Therefore, further investigations are required to identify the pathogenesis of LSCC. METHODS AND RESULTS: In order to search for new LSCC biomarkers, we have analysed the expression of the HMGA family members, HMGA1 and HMGA2, by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry. HMGA proteins are usually absent in the healthy adult tissues. In contrast, their constitutive expression is a feature of several neoplasias, being associated with a highly malignant phenotype and reduced survival. Here, we report HMGA2 overexpression in larynx carcinomas. Conversely, HMGA1 does not show any differences in its expression between normal and carcinoma tissues. Interestingly, HMGA2 overexpression appears associated with that of two HMGA1-pseudogenes, HMGA1P6 and HMGA1P7, acting as a sponge for HMGA1- and HMGA2-targeting microRNAs and involved in several human cancers. CONCLUSIONS: Therefore, HMGA2 overexpression appears to be a strong feature of larynx carcinoma, supporting its detection as a valid tool for the diagnosis of these malignancies.

Toll-like receptor 2 rs4696480 polymorphism and risk of oral cancer and oral potentially malignant disorder.

OBJECTIVES: The aim of this study was to identify the possible association between TLR polymorphisms and an increased risk of developing head and neck cancer, including oral (OSCC) and laryngeal squamous cell carcinoma (LSCC), and oral potentially malignant disorders, such as oral lichenoid disease (OLD), including oral lichen planus (OLP) and oral lichenoid lesions (OLL). DESIGN: This case-control study included 40 OSCC, 35 LSCC, 175 OLD (129 OLP and 46 OLL) patients and 89 healthy controls, all of them from the Basque Country, Spain. Genetic polymorphisms in TLR1, TLR2, TLR4, TLR6, TLR9, and TLR10 were genotyped by TaqMan® assays or pyrosequencing. RESULTS: The chi-square analysis showed that the variant A of the SNP TLR2-rs4696480 polymorphism significantly increased the risk of OSCC (p=0.03) and OLL (p=0.02). CONCLUSIONS: The TLR2-rs4696480 polymorphism may be relevant to OSCC and OLL susceptibility in this population encouraging further studies on the TLR2 pathway and its possible association with this group of oral potentially malignant disorders and oral cancer. This may also prove the use of TLR polymorphisms as risk markers for oral and laryngeal cancer.

Association between interleukin-17 gene polymorphisms and the risk of laryngeal cancer in a Chinese population.

IL-17 is associated with the occurrence and development of laryngeal cancer. However, no study has reported the association between IL-17 polymorphisms and laryngeal cancer susceptibility. Therefore, we analyzed the association of three polymorphism loci (rs2275913, 197 G/A; rs3748067, 383 A/G; and rs763780, 7488 T/C) of IL-17A and IL-17F with laryngeal cancer in the Chinese population. A case-control study was performed with 325 patients and 325 controls. Polymorphisms were detected by polymerase chain reaction and sequencing methods. SPSS17.0 software was used for statistical analysis. Allele and genotype frequencies of IL-17A rs2275913 were significantly different between patients and controls (P < 0.05). Frequencies of rs2275913 (197 G/A) AA and GA+AA genotypes compared to the GG genotype were significantly higher in patients than in controls, indicating the association of these genes with laryngeal cancer susceptibility; adjusted OR values were 2.54 (1.50-4.23) and 1.62 (1.19-2.17), respectively. Furthermore, individuals with the GA+AA genotype, compared to the GG genotype, aged ≤60 years, with smoking and alcohol consumption habits, and without a family history of cancer showed a higher cancer risk (OR = 2.74, 95%CI = 1.41-5.23; OR = 2.11, 95%CI = 1.21-3.55; OR = 1.91, 95%CI = 1.02-3.70; OR = 1.99, 95%CI = 1.08-3.39, respectively). In conclusion, the rs2275913 IL-17A (197 G/A) is associated with the incidence and development of laryngeal cancer in the Chinese population, and the AA and GA+AA genotypes harbor a high laryngeal cancer risk.

MiR-21 as prognostic biomarker in head and neck squamous cell carcinoma patients undergoing an organ preservation protocol.

Despite progress in the treatment of head and neck squamous cell carcinoma (HNSCC) in recent decades, including new surgical techniques, radiotherapy advances and chemotherapy schedules, the prognosis for the affected patients has not improved at the same pace, and still, most HNSCC patients are diagnosed in advanced stages. To increase their survival, the development of better screening methods for early detection is required and appropriate tailored therapeutic interventions are desired. The aim of the present study was to evaluate miRNAs as prognostic biomarkers in patients undergoing organ preservation protocol for locally advanced HNSCC. For this purpose, we assessed the global miRNA expression profile of 15 HNSCC patients ('screening set') to identify miRNAs differentially expressed in responders and non-responders to therapy. Four miRNAs differentially expressed in HNSCC samples from the 'screening set' were validated in a different cohort of patients (47 samples - 'validation set'). The results from the 'validation set' showed that the higher expression of one of these miRNAs, miR-21, was negatively associated with the treatment response to the organ preservation protocol (p=0.029). A multivariate analysis showed that, in a model adjusted for age, tumor site, p16 immunoexpression and tumor resectability, high expression of miR-21 remained an independent predictor of poor response to the organ preservation protocol (OR=5.69; 95%CI 1.27-25.58; p=0.023), together with clinical stage IV (OR=5.05; 95%CI 1.22-20.88; p=0.025). Furthermore, considering the entire cohort, patients with high expression of miR-21 had worse survival. A multivariate Cox regression analysis also showed miR-21 (HR=2.05; 95%CI 1.05-4.02; p=0.036) and clinical stage IV (HR=3.17; 95%CI 1.49-6.77; p=0.003) as independent prognostic factors (model adjusted for age, tumor site, tumor resectability, and sets 'screening' or 'validation').In conclusion, the results of this study suggest that the evaluation of miR-21 expression could be an important tool for treatment planning and a prognosis predictior for HNSCC patients undergoing organ preservation protocols.

Association between XRCC1 polymorphisms and laryngeal cancer susceptibility in a Chinese sample population.

Laryngeal cancer is the major malignant tumor affecting the upper respiratory tract. Previous studies have reported on the association between XRCC1 genetic polymorphisms and risk of laryngeal cancer, but with conflicting results. In this study, we attempted to assess the association between XRCC1 Arg194Trp, Arg280His and Arg399Gln polymorphisms and risk of laryngeal cancer in a Chinese population. A total of 126 laryngeal cancer patients and 254 control subjects were recruited to this study from the Second Medical College of Jinan University between December 2013 and May 2015. The XRCC1 Arg194Trp, Arg280His, and Arg399Gln polymorphic sites were genotyped by polymerase chain reaction-restriction fragment length polymorphism. Our results revealed a significant association between the AA genotype of XRCC1 Arg280His [odds ratio (OR) = 2.51, 95% confidence interval (CI) = 1.29-4.87, P = 0.01] and an increased risk of laryngeal cancer susceptibility compared to the GG genotype. Moreover, the A allele showed a higher risk of laryngeal cancer susceptibility compared to the G allele (OR = 1.63, 95%CI = 1.19-2.50, P = 0.002). In conclusion, the results of our study suggest that the AA genotype and A allele of the XRCC1 Arg280His polymorphism are associated with an increased laryngeal cancer risk in a Chinese population.

HOX genes: potential candidates for the progression of laryngeal squamous cell carcinoma.

Laryngeal squamous cell carcinoma (LSCC) is a very aggressive cancer, considered to be a subtype of the head and neck squamous cell carcinoma (HNSCC). Despite significant advances in the understanding and treatment of cancer, prognosis of patients with LSCC has not improved recently. In the present study, we sought to understand better the genetic mechanisms underlying LSCC development. Thirty-two tumor samples were collected from patients undergoing surgical resection of LSCC. The samples were submitted to whole-genome cDNA microarray analysis aiming to identify genetic targets in LSCC. We also employed bioinformatic approaches to expand our findings using the TCGA database and further performed functional assays, using human HNSCC cell lines, to evaluate viability, cell proliferation, and cell migration after silencing of selected genes. Eight members of the homeobox gene family (HOX) were identified to be overexpressed in LSCC samples when compared to normal larynx tissue. Quantitative RT-PCR analysis validated the overexpression of HOX gene family members in LSCC. Receiver operating characteristic (ROC) statistical method curve showed that the expression level of seven members of HOX gene family can distinguish tumor from nontumor tissue. Correlation analysis of clinical and gene expression data revealed that HOXC8 and HOXD11 genes were associated with the differentiation degree of tumors and regional lymph node metastases, respectively. Additionally, siRNA assays confirmed that HOXC8, HOXD10, and HOXD11 genes might be critical for cell colony proliferation and cell migration. According to our findings, several members of the HOX genes were overexpressed in LSCC samples and seem to be required in biological processes involved in tumor development. This suggests that HOX genes might play a critical role in the physiopathology of LSCC tumors.

Expression of miR-296-5p as predictive marker for radiotherapy resistance in early-stage laryngeal carcinoma.

PURPOSE: Definitive radiation therapy is the mainstay of treatment for early stage laryngeal squamous cell carcinoma (LSCC). However, up to 30% of the patients do not respond to radiotherapy. Unfortunately, we are unable to predict which tumors are likely to respond to radiation, and which will be resistant and persist. Therefore, the development of novel markers to predict response to radiotherapy is urgently needed. This study was designed to evaluate the expression pattern of microRNAs (miRNAs) in LSCC in order to identify markers capable of segregating radioresistant and radiosensitive tumors and to investigate the relationship between the expression of these miRNAs and the prognosis of LSCC. METHODS: The expression profile of 667 miRNAs was determined in an initial screening of nine early-stage LSCC samples (5 radioresistant and 4 radiosensitive) using TaqMan Low-Density Array (TLDA). Real-time polymerase chain reactions were performed to validate the expression of selected miRNAs in an expanded LSCC cohort (20 radioresistant and 14 radiosensitive). The miRNA expression level was scored as high or low based on the median of the expression in the LSCC samples. RESULTS: A comprehensive miRNA expression profiling enabled the identification of four miRNAs (miR-296-5p miR-452, miR-183* and miR-200c) differentially expressed in radioresistant LSCC. Moreover, the analysis of additional 34 LSCC samples, confirmed the expression of miR-296-5p as significantly related to radioresistance (p = 0.002) as well as an association of this marker with recurrence (p = 0.025) in early stage laryngeal cancer. CONCLUSIONS: This study indicates that miR-296-5p expression is associated with resistance to radiotherapy and tumor recurrence in early stage LSCC, showing the feasibility of this marker as a novel prognostic factor for this malignance. Furthermore, miR-296-5p expression could be helpful in the identification of tumors resistant to radiotherapy; thus aiding the clinicians in the choice of the best therapeutic scheme to be used in each case.

Do genetic polymorphisms modulate response rate and toxicity of Cisplatin associated with radiotherapy in laryngeal squamous cell carcinoma?: a case report.

UNLABELLED: Cisplatin (CDDP) plus radiotherapy (RT) has been used to treat advanced laryngeal squamous cell carcinoma (LSCC) patients. Single nucleotide polymorphisms (SNPs) may be responsible for differences in chemo/radiosensitivity and side effects in those patients. We reported an advanced LSCC patient, who obtained durable complete response and unexpected pronounced toxicity during CDDP and RT, possibly due to SNPs in genes that modulate the effects of this therapeutic modality. CASE PRESENTATION: A 30-year-old man with advanced LSCC obtained durable complete response and severe alopecia and pancytopenia after standard and reduced doses of CDDP and RT. Analyses of SNPs revealed that the patient presented GSTT1 deletion, variant MSH3 1045ThrThr, wild GSTP1 105IleIle, and wild BAX -248GG genotypes, which were previously described in association with abnormal detoxification, DNA repair, and damaged cell apoptosis, respectively. Seven other advanced LSCC patients with GSTT1 gene, MSH3 AlaAla or AlaThr, GSTP1 IleVal or ValVal, and BAX GA or AA genotypes served as controls of the study. Only 1 control presented complete response; the other 6 controls obtained partial response of short duration. Four and 3 controls presented grade 1 or 2 and grade 3 anemia or leukopenia during treatment, respectively. The CDDP level in urine collected after CDDP infusion in the reported patient was lower than the median value obtained in controls, suggesting a higher amount of intracellular CDDP in the reported case.The data suggest, for the first time, that inherited abnormalities in intracellular detoxification of CDDP, DNA repair of lesions induced by CDDP and RT, and damaged cell apoptosis may alter treatment response and toxicity in LSCC, but should be confirmed by large pharmacogenomic studies.

Assessment of MLL methyltransferase gene expression in larynx carcinoma.

Larynx cancer is the second most common type of cancer among all head and neck cancers. Deregulation of epigenetic effectors, including altered expression of histone methyltransferases from the MLL (mixed lineage leukemia) family, have been reported in many cancer types, yet little is known concerning their involvement in larynx cancer. Our objective was to determine the expression profile of MLL genes in larynx carcinoma and normal adjacent tissues and correlate this profile to tumor characteristics. We analyzed the expression profile of 5 MLL genes in 13 cases of larynx carcinoma and their adjacent non-tumor tissues using quantitative real-time PCR. MLL3 was significantly downregulated in tumor samples compared to their normal counterparts, and all MLL genes showed decreased expression in advanced tumors compared to tumors in the initial stage. Altered expression in a single MLL gene was associated with a similar alteration in the other MLL genes, revealing a strong correlation of expression in each individual patient. In conclusion, MLL genes may have similar transcriptional control, and decreased expression of these genes may contribute to larynx cancer progression.