Polymorphism of the stress protein HSP70-2 gene is associated with the susceptibility to the nasopharyngeal carcinoma

Methylated tumor suppressor gene SCARA5 inhibits the proliferation, migration and invasion of nasopharyngeal carcinoma

Background: SCARA5 may play an important role in nasopharyngeal carcinoma. Materials & methods: PCR and immunohistochemistry were used to detect the expression and promoter methylation of SCARA5. Cell proliferation assays, spheroid culture, flow cytometry analysis, Transwell assays and xenotransplantation tests were utilized to determine the functional effects of SCARA5. RNA-sequencing, western blotting, immunofluorescence and dual-luciferase reporter assays were used to assess SCARA5-mediated outcomes. Results: SCARA5 was downregulated by promoter methylation. Overexpression of SCARA5 inhibited cell migration, invasion and proliferation. SCARA5 enhanced nasopharyngeal carcinoma cell sensitivity to chemotherapy with cisplatin and 5-fluorouracil. SCARA5 drives tumor apoptosis by downregulating HSPA2. Conclusion: SCARA5 may be a useful clinical marker in nasopharyngeal carcinoma.

Proteomic analysis identifies potential markers in small white and small yellow follicle development in chickens

Extensive knowledge of follicular development is imperative for improving egg production in chickens. The functional role of follicles to produce oocytes (eggs) is well recognised; however, specific markers associated with follicle development have been poorly explored. Therefore, a tandem mass tag based proteomic technique was used to identify the status of the proteome of small white follicles (1-4mm) and small yellow follicles (6-8mm). Analysis of differentially expressed proteins (DEP, Fold Change>1.2, P -value<0.05) demonstrated a total of 92 proteins (n =92), of which 35 (n =35) were upregulated and 57 were downregulated. DEP were further used for gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathways. The GO analysis found that DEP were mainly associated with the RNA metabolic process, cellular component organisation, peptide biosynthetic process and protein folding, thereby suggesting a key role in the follicle development process. Kyoto Encyclopedia of Genes and Genomes enrichment pathway analysis of the DEP substantiated the findings of GO analysis and described that DEP are involved in regulation of the cytoskeleton, carbon metabolism and amino acid biosynthesis. The validation of proteomic data through real-time quantitative polymerase chain reaction suggested HSPA8, HSPA2, SOD1 and FKPB3 as potential markers of small white and small yellow follicle development. This study demonstrates an understanding of proteome dynamics and represents the most comprehensive information on the entire Guangxi Ma chicken follicular proteome.

The protein-protein interaction network of intestinal gastric cancer patients reveals hub proteins with potential prognostic value

BACKGROUND

Gastric cancer (GC) is the third leading cause of cancer worldwide. According to the Lauren classification, gastric adenocarcinoma is divided into two subtypes: diffuse and intestinal. The development of intestinal gastric cancer (IGC) can take years and involves multiple factors.

OBJECTIVE

To investigate the protein profile of tumor samples from patients with IGC in comparison with adjacent nontumor tissue samples.

METHODS

We used label-free nano-LC-MS/MS to identify proteins from the tissues samples. The results were analyzed using MetaCore™ software to access functional enrichment information. Protein-protein interactions (PPI) were predicted using STRING analysis. Hub proteins were determined using the Cytoscape plugin, CytoHubba. Survival analysis was performed using KM plotter. We identified 429 differentially expressed proteins whose pathways and processes were related to protein folding, apoptosis, and immune response.

RESULTS

The PPI network of these proteins showed enrichment modules related to the regulation of cell death, immune system, neutrophil degranulation, metabolism of RNA and chromatin DNA binding. From the PPI network, we identified 20 differentially expressed hub proteins, and assessed the prognostic value of the expression of genes that encode them. Among them, the expression of four hub genes was significantly associated with the overall survival of IGC patients.

CONCLUSIONS

This study reveals important findings that affect IGC development based on specific biological alterations in IGC patients. Bioinformatics analysis showed that the pathogenesis of IGC patients is complex and involves different interconnected biological processes. These findings may be useful in research on new targets to develop novel therapies to improve the overall survival of patients with IGC.

Downregulation of HSPA2 inhibits proliferation via ERK1/2 pathway and endoplasmic reticular stress in lung adenocarcinoma

Background

To explore the mechanisms of HSPA2 downregulation in inhibiting the proliferation of lung adenocarcinoma.

Methods

We obtained 85 specimens of human lung adenocarcinoma and specimens of adjacent nontumor tissues from the First Affiliated Hospital, School of Medicine, Zhejiang University. We then analyzed the expression of HSPA2 in these tissues and in lung adenocarcinoma and normal lung cell lines. Human lung adenocarcinoma cell lines were transfected with siRNA silencing HSPA2 and subjected to colony forming, Thiazolyl blue tetrazolium bromide (MTT), propidium iodide flow cytometry, immunofluorescence assay and western blotting to explore the causes of the reduction in the proliferation of lung adenocarcinoma cells and the endoplasmic reticulum stress induced by HSPA2 downregulation. Finally, we confirmed these mechanisms via rescue assay.

Results

Greater HSPA2 expression was found in the lung adenocarcinoma specimens than in the specimens of adjacent nontumor tissues, and greater expression was found in lung adenocarcinoma cell lines than in normal cell lines. HSPA2 knockdown via siRNA reduced proliferation and led to G1/S phase cell cycle arrest in the lung adenocarcinoma cell lines. G1/S phase cell cycle arrest triggered by HSPA2 downregulation could be attributed, at least in part, to phosphorylation and activation of the Erk1/2 pathway and probably to activation of IRE1α/PERK-mediated endoplasmic reticulum stress.

Conclusions

HSPA2 plays an important role in the origin and development of lung adenocarcinoma. It is thus deserving of further study as a promising clinical therapeutic target.

Heat-shock protein 70 (HSP70) polymorphisms affect the risk of coke-oven emission-induced neurobehavioral damage

OBJECTIVES

Epidemiology studies indicated that coke-oven workers with long-term exposure to polycyclic aromatic hydrocarbons (PAHs) often have some neurobehavioral abnormalities especially impairment for cognitive function, while the underlying mechanisms are not fully understood. Numerous studies have indicated the antioxidant and anti-apoptosis roles of heat shock protein 70 (Hsp70). The genetic polymorphisms in HSP70 genes are associated with multiple diseases including neurotoxicity. However, it is unclear whether HSP70 polymorphisms are related to the neurotoxicity of PAH. We, therefore, investigate the possible association between HSP70 polymorphisms and neurobehavioral abnormalities.

METHODS

188 coke-oven workers and 137 control workers were recruited in this study. Emotional and cognitive function was assessed using the WHO/NCTB. HSP70 polymorphisms (HSP70-1 G190C, HSP70-2 G1267 A and HSP70-hom T2437C) were checked by PCR-RFLP.

RESULTS

The results indicated that HSP70-1 CC genotypes in coke-oven workers were associated with poor neurobehavioral performance such as the attention /response speed and visual perception/memory, while the HSP70-2 AA genotypes were associated with lower short-term auditory memory.

CONCLUSIONS

HSP70-1 CC and HSP70-2 AA genotypes in coke-oven workers may increase the risk for neurobehavioral damage, especially attention, learning and memory.

No association of TNF-α-308G/A polymorphisms with head and neck cancer risk: A PRISMA-compliant meta-analysis

BACKGROUND

A number of studies had reported the association between tumor necrosis factor-alpha (TNF-α) gene polymorphisms and head and neck cancer (HNC) risk. However, the results remained controversial. Therefore, we performed a meta-analysis to derive a more precise evaluation of the association between TNF-α-308G/A polymorphism and overall HNC risk and evaluated influence of cancer types and ethnicities.

METHODS

A systematic literature search was performed using Pubmed, Embase, Cochrane Library, and Web of science. In total, we identified 15 studies including 2005 cancer cases and 2876 controls to evaluate the association of TNF-α-308G/A polymorphism with risk for HNC.

RESULTS

Overall, there was no significant association between TNF-α-308G/A polymorphism and the risk of HNC. Furthermore, subgroup analyses were performed according to the types of tumor and the ethnicities, we also found there was no significant association between TNF-α-308G/A polymorphism and the risk of NPC and OC, and European and Asian populations had no statistically significant difference in the relationship of TNF-α-308G/A polymorphism and HNC susceptibility.

CONCLUSION

This meta-analysis indicates that the TNF-α-308G/A polymorphism is not associated with HNC risk. In the future, large and well-designed case-control studies are needed to validate our findings.

Overexpressed HSPA2 correlates with tumor angiogenesis and unfavorable prognosis in pancreatic carcinoma

Heat shock-related 70-kDa protein 2 (HSPA2) is known to correlate with tumor development and progression. This work aimed to determine the expression and prognostic roles of HSPA2 in pancreatic carcinoma. Tumor and their corresponding non-tumor tissues were obtained from 80 patients with pancreatic carcinoma. HSPA2 expression in tumor and non-tumor tissues was evaluated by immunohistochemistry. Expression of vascular endothelial growth factor (VEGF) and CD31 in tumor tissues were also evaluated by immunostaining. The relationships of HSPA2 with clinicopathological data, tumor angiogenesis and prognosis were analyzed. The results showed that HSPA2 expression was significantly elevated in tumor tissues compared with adjacent non-tumor tissues (P < 0.05). High HSPA2 expression was significantly associated with aggressive clinicopathological characteristics. HSPA2 staining was positively correlated with VEGF (r = 0.466, P < 0.001) and microvessel density (MVD) (r = 0.366, P = 0.001) in tumor tissues. Patients with high HSPA2 expression showed worse relapse-free survival (RFS) (P < 0.001) and overall survival (OS) (P < 0.001) than those with low HSPA2 expression. Multivariate analysis indicated that high HSPA2 expression was an independent predictor for poor RFS (P < 0.001) and OS (P = 0.001). Taken together, overexpressed HSPA2 is correlated with tumor angiogenesis and poor prognosis in pancreatic carcinoma. HSPA2 may play an important role in tumor progression, and serve as a potential biomarker for the prediction of adverse prognosis in pancreatic carcinoma.

Clinical, cellular, and bioinformatic analyses reveal involvement of WRAP53 overexpression in carcinogenesis of lung adenocarcinoma

Lung cancer, of which non-small cell lung cancer accounts for 80%, remains a leading cause of cancer-related mortality and morbidity worldwide. Our study revealed that the expression of WD repeat containing antisense to P53 (WRAP53) is higher in lung-adenocarcinoma specimens than in specimens from adjacent non-tumor tissues. The prevalence of WRAP53 overexpression was significantly higher in patients with tumor larger than 3.0 cm than in patients with tumor smaller than 3.0 cm. The depletion of WRAP53 inhibits the proliferation of lung-adenocarcinoma A549 and SPC-A-1 cells via G1/S cell-cycle arrest. Several proteins interacting with WRAP53 were identified through co-immunoprecipitation and liquid chromatography/mass spectrometry. These key proteins indicated previously undiscovered functions of WRAP53. These observations strongly suggested that WRAP53 should be considered a promising target in the prevention or treatment of lung adenocarcinoma.

Matrix metalloproteinase-1 (MMP1) polymorphism is associated with lowered risk of nasopharyngeal carcinoma in Asian population

Data on the association between -1607 1G > 2G polymorphism in the promoter region of matrix metalloproteinase-1 (MMP1) and nasopharyngeal carcinoma (NPC) are conflicting. The aim of this study was to confirm whether this polymorphism was a causative factor of NPC. We searched PubMed, Embase, and China National Knowledge Infrastructure (CNKI) for studies on the present topic. A total of four publications (1,044 NPC patients and 1,284 healthy control subjects) were included and meta-analysis was performed to assess the association between -1607 1G > 2G polymorphism and NPC risk. Odds ratio (OR) with 95 % confidence interval (95 % CI) was calculated for 1G1G versus 2G2G, 1G1G + 1G2G versus 2G2G, 1G1G versus 1G2G + 2G2G, 1G versus 2G, and 1G2G versus 2G2G contrast models. Meta-analysis results showed significantly reduced risk of NPC associated with the 1G1G versus 2G2G, 1G versus 2G and 1G2G versus 2G2G contrast models (OR = 0.61, 95 % CI 0.49-0.77; OR = 0.78, 95 % CI 0.65-0.92; OR = 0.86, 95 % CI 0.74-0.99, respectively). When we continued to perform subgroup analysis by ethnicity, the significant association persisted in Asian population and was most pronounced under the 1G2G versus 2G2G model (OR = 0.85, 95 % CI 0.73-0.99). These data suggested that MMP1 -1607 1G > 2G polymorphism was associated with reduced risk of NPC, particularly in the population of Asian descent.

The interplay of host genetic factors and Epstein-Barr virus in the development of nasopharyngeal carcinoma

The interplay between host cell genetics and Epstein-Barr virus (EBV) infection contributes to the development of nasopharyngeal carcinoma (NPC). Understanding the host genetic and epigenetic alterations and the influence of EBV on cell signaling and host gene regulation will aid in understanding the molecular pathogenesis of NPC and provide useful biomarkers and targets for diagnosis and therapy. In this review, we provide an update of the oncogenes and tumor suppressor genes associated with NPC, as well as genes associated with NPC risk including those involved in carcinogen detoxification and DNA repair. We also describe the importance of host genetics that govern the human leukocyte antigen (HLA) complex and immune responses, and we describe the impact of EBV infection on host cell signaling changes and epigenetic regulation of gene expression. High-power genomic sequencing approaches are needed to elucidate the genetic basis for inherited susceptibility to NPC and to identify the genes and pathways driving its molecular pathogenesis.

Association between the HSPA1B ±1267A/G polymorphism and cancer risk: a meta-analysis of 14 case-control studies

BACKGROUND

Previous epidemiological studies have suggested a potential role of the HSPA1B±1267A/G polymorphism in risk of developing cancer. However, the results were inconsistent. Therefore, we performed this meta-analysis to summarize the possible association with cancer risk.

MATERIALS AND METHODS

We retrieved relevant articles from PubMed, EMBASE, ISI Web of Science, Chinese Biomedical Literature and Chinese National Knowledge Infrastructure. Studies were selected using specific criteria. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess those associations. All analyses were performed using STATA software.

RESULTS

Fourteen case-control studies, including 1, 834 cancer cases and 2, 028 controls were included in this meta-analysis. Overall, the results indicated that the G allele of HSPA1B gene ±1267A/G was significantly associated with an increased cancer risk in all genetic models (G vs A: OR=1.51, 95%CI 1.17-1.95, p=0.001; GG vs AA: OR=2.93, 95%CI 1.50-5.74, p=0.002; AG vs AA: OR=1.48, 95%CI 1.10-1.98, p=0.009; GG/AG vs AA: OR=1.69, 95%CI 1.22-2.33, p=0.001; GG vs

AG/AA

OR=2.31, 95%CI 1.24-4.32, p=0.009). In the subgroup analysis stratified by ethnicity, a significant association was identified in Caucasians (G vs A: OR=1.35, 95%CI 1.08-1.69, p=0.008; GG/AG vs AA: OR=1.36, 95%CI 1.09-1.70, p=0.007), but not in Asians. In the stratified analysis by cancer types, individuals with the G allele showed an increased risk of hepatocellular carcinoma compared with carriers of the A allele (OR=2.40, 95%CI 1.47-3.91, p< 0.001). Inversely, individuals with the GG genotype showed a decreased risk of gastric cancer compared with carriers of the AG/GG genotypes (GG vs

AG/AA

OR=0.39, 95%CI 0.20-0.70, p=0.007).

CONCLUSIONS

This meta-analysis suggests associations between the HSPA1B ±1267A/G polymorphism and risk of cancer. However, this association might be Caucasian-specific and the G allele of this polymorphism probably increases risk of hepatocellular carcinoma while decreasing risk of gastric cancer. Further well-designed studies based on larger sample sizes are needed to validate these findings.

Contribution of susceptibility locus at HLA class I region and environmental factors to occurrence of nasopharyngeal cancer in Northeast India

High incidence of nasopharyngeal carcinoma (NPC) has been reported from China, Southeast Asia and Northeast (NE) region of India. Populations at geographic regions having higher incidence of NPC display human leukocyte antigen (HLA) distribution patterns different from areas having low incidence. The current study has investigated the contribution of environmental risk factors and ethnic variation of microsatellite markers in HLA region for the high incidence of NPC in NE India. Genotyping of HLA region using 33 microsatellite markers by fragment length analysis was done in 220 study subjects (120 NPC patients and 100 healthy controls). Association analysis showed two adjacent microsatellite markers HL003 (allele 121) and D6S2704 (allele 218) in the HLA class I region having association with high risk of NPC while allele 127 of HL003 and allele 255 of D6S2678 conferred a protective effect. The environmental factors mainly use of firewood (odds ratio (OR) = 3.797385, confidence interval (CI) = 1.97-7.30, P < 0), living in mud house (OR = 3.46, CI = 1.19-10.08, P = 0.022) and consumption of alcohol (OR = 2.11, CI = 1.02-4.37, P = 0.043) were found as major risk factors for NPC. Higher-order interaction showed combination of smoked food consumption and firewood use for cooking in multifactor dimensionality reduction (MDR) analysis and interaction of non-firewood users, non-ventilated houses and residence in mud houses in classification and regression tree (CART) analysis as the significant risk factors for NPC. Expression of Epstein-Barr virus (EBV) RNA was found in 92% (23/25) of NPC cases suggesting its significant role in NPC aetiopathogenesis. This study identified association of NPC with a susceptibility locus in the HLA class I region which has complex interaction with viral DNA and environmental factors.

Heat shock protein 70 gene polymorphisms and cancer risk: a meta-analysis

The polymorphisms in the three main heat shock protein 70 (HSP70-1, HSP70-2, and HSP70-hom) genes were identified to be associated with cancer risk. However, the results are inconsistent. We perform a meta-analysis to evaluate the association between the three HSP70 polymorphisms and cancer risk. Relevant studies were identified using PubMed, Web of Science, Chinese National Knowledge Infrastructure (CNKI), and Wanfang databases up to March 29, 2014. The cancer risk associated with the HSP70 polymorphisms was estimated for each study by odds ratios (OR) together with its 95% confidence interval (CI), respectively. Twenty case-control studies from eighteen publications were included; a significant association was observed for HSP70-2 polymorphism (dominant model: OR = 1.53, 95% CI: 1.11–2.09; recessive model: OR = 1.91, 95% CI: 1.06–3.45; AG versus AA: OR = 1.38, 95% CI: 1.03–1.84; GG versus AA: OR = 2.34, 95% CI: 1.21–4.54), while there was no significant association for HSP70-1 and HSP70-hom polymorphisms. Besides, in stratification analyses by ethnicity, cancer type, and source of control, significant association was detected for HSP70-2 polymorphism, while for HSP70-hom polymorphism, we found a significant association in hospital-based population under homozygote comparison model. This meta-analysis suggests that the HSP70-2 polymorphism rather than HSP70-hom and HSP70-1 polymorphisms was associated with the risk of cancer.

Polymorphisms in genes coding for HSP-70 are associated with gastric cancer and duodenal ulcer in a population at high risk of gastric cancer in Costa Rica

BACKGROUND AND AIMS

Costa Rica has among the highest incidence and mortality rates for gastric cancer worldwide. The reasons for this are largely unknown. Polymorphisms of inflammatory response genes including genes encoding heat shock proteins (HSP) have been shown to be associated with the risk of gastric cancer in some populations. This study addresses the possible association between the HSP70-2 +1267 and HSP70-Hom +2437 polymorphisms and the risk of developing gastric cancer in a high-risk population in Costa Rica.

METHODS

DNA from 39 individuals diagnosed with gastric cancer, 79 healthy controls, 55 individuals with chronic gastritis and 52 individuals with duodenal ulcer was genotyped for the polymorphisms HSP70-2 +1267 and HSP70-Hom +2437 by RFLP. Logistic regression analysis was used to determine possible associations with the diagnoses and lineal regression analysis to determine associations with blood pepsinogen (PGs) levels as measured by serology.

RESULTS

The GA genotype of HSP70-2 was associated with increased risk of gastric cancer (OR = 3.42; 95% CI = 1.27-9.21; p = 0.015) and duodenal ulcer (OR = 2.57; 95% CI = 1.03-6.36; p = 0.042) as compared to the GG genotype. Persons with C carrier genotypes of HSP70-Hom were significantly less susceptible to gastric cancer than those with the TT genotype (OR = 0.29; 95% CI = 0.09-0.87; p = 0.027). The C carrier genotype was associated with lower PGI concentrations but none of the polymorphisms were associated with PGI/PGII.

CONCLUSIONS

Polymorphisms of HSP70 genes are associated with the development of gastric cancer and duodenal ulcers in a population at high risk for gastric cancer in Costa Rica.

Overexpression of HSPA2 is correlated with poor prognosis in esophageal squamous cell carcinoma

Background

Heat shock-related 70 kDa protein 2 (HSPA2) has been identified as a potential cancer-promoting protein expressed at abnormal levels in a subset of cancers. However, its important role in esophageal squamous cell carcinoma (ESCC) is hardly known by people. The purpose of this study is to assess HSPA2 expression and to explore its role in ESCC.

Methods

Thirty ESCC samples, paired adjacent non-cancerous tissues and normal esophageal tissues, were collected for HSPA2 detection by quantitative RT-PCR (qRT-PCR) and western blotting. Additionally, the expression of HSPA2 in ESCC and adjacent non-cancerous tissues from 120 patients was analyzed by immunohistochemistry, and correlated with clinicopathological parameters and patients’ outcome.

Results

HSPA2 mRNA and protein were overexpressed in ESCC tissues. Overexpression of HSPA2 was significantly associated with primary tumor, TNM stage, lymph node metastases and recurrence, respectively (all, P <0.05). Kaplan-Meier curves showed that elevated HSPA2 expression was associated with shorter disease-free survival and overall survival in ESCC patients. Cox multivariate regression analysis revealed that overexpression of HSPA2 was an independent prognostic factor in disease-free survival and overall survival for ESCC patients (hazard ratio was 2.115 and 2.210, respectively, P <0.05).

Conclusions

Our findings demonstrate that overexpression of HSPA2 may contribute to the malignant progression of ESCC and present a novel prognostic indicator for ESCC patients.

N,N'-dinitrosopiperazine--mediated heat-shock protein 70-2 expression is involved in metastasis of nasopharyngeal carcinoma

N,N′-Dinitrosopiperazine (DNP) is invovled in nasopharyngeal carcinoma (NPC) development and metastasis, and it shows organ specificity to the nasopharyngeal epithelium. Herein, we demonstrate that DNP induces heat-shock protein (HSP) 70-2 expression in NPC cells (6-10B) at a non-cytotoxic concentration. DNP induced HSP70-2 expression in a dose- and time- dependent manner, but showed no effect on other HSP70 family members. Furthermore, DNP also increased HSP70-2 RNA transcription through directly binding to the hypoxia-responsive elements (HRE) and heat shock elements (HSE) located in the HSP70-2 promoter. DNP-mediated HSP70-2 expression might act through enhancing the transcription of HSP70-2 RNA. Importantly, DNP induced motility and invasion of 6-10B cells dose- and time-dependently, and DNP-mediated NPC metastasis was confirmed in nude mice, which showed high HSP70-2 expression in the metastatic tumor tissue. However, the motility and invasion of NPC cells that were stably transfected using short interfering RNA against HSP70-2 could not effectively induce DNP. These results indicate that DNP induces HSP70-2 expression through increasing HSP70-2 transcription, increases the motility and invasion of cells, and promotes NPC tumor metastasis. Therefore, DNP mediated HSP70-2 expression may be an important factor of NPC-high metastasis.

TNF-α-308G/A polymorphisms and nasopharyngeal cancer risk: a meta-analysis

Previous evidence has indicated that the polymorphism of tumor necrosis factor-alpha (TNF-α) is a risk factor for various cancers, however, the association between TNF-α-308G/A polymorphism and nasopharyngeal carcinoma (NPC) remains controversial and ambiguous. The aim of this study is to clarify the association between TNF-α polymorphism and NPC using meta-analysis. A meta-analysis based on five eligible case-control studies involving 499 cases and 1,470 controls was carried out to summarize the data on the association between TNF-α-308G/A polymorphism and NPC risk. Odds ratios (OR) with 95 % confidence intervals (95 % CI) were used to assess the strength of this association in the fixed-effect model. The pooled analyses showed no significant association between TNF-α-308G/A polymorphism and NPC (AA vs. GG: OR = 1.38, P = 0.193; GA vs. GG: OR = 0.92, P = 0.585; GA + AA vs. GG: OR = 1.00, P = 0.972; AA vs. GA + GG: OR = 1.44, P = 0.138). We also categorized by geographic location (non-Asian or Asian) for subgroup analysis; the results also showed no significant association between TNF-α-308G/A polymorphism and NPC risk in all of the comparisons. No publication bias was observed in this study (t = -0.11, P = 0.918, 95 % CI = -4.893-4.559). No significant association was found between TNF-α-308G/A polymorphism and the risk for NPC.

Interaction between hypertension and HSP70 variants increase the risk of cerebral ischemia in Chinese Han population: an association study

Cerebral infarction has become one of the leading diseases and a major mortality factor around the world. Atherosclerosis is recognized as one of the important causes of ischemic stroke. Recently, accumulating evidences have indicated that the anti-inflammatory and anti-apoptotic functions of the HSP70 family play an important role in cerebral ischemia. However, the association between HSP70 SNPs and ischemic stroke was also not well established. We chose 101 cases of cerebral ischemia and 100 healthy people from the Chinese Han population as our study subjects, and PCR-RFLP was employed to analyze HSP70 polymorphisms: HSP70-1+190G/C, HSP70-2+1267A/G and HSP70-hom+2437T/C. There were no significant differences in +1267A/G allele or genotype frequencies between patients with stroke and healthy controls. However, genotypes of +190CG and +2437TT were differentially distributed between the patients and controls. A significant difference of T allele distribution in the HSP70-hom+2437T/C site was observed. Logistic regression analysis indicated that genotypes of +190CG, +2437TT and T allele in HSP70-hom were risk factors of ischemic stroke. Moreover, the study has formulated that the interactions between hypertension and +190CG or +2437TT may increase the risks of ischemic stroke. The results from this study have suggested a clinical indicator for assessing the possibilities of cerebral stroke, and supply basis to clinicians to give precaution to people who are at risk of stroke.

HSP90, HSPA8, HIF-1 alpha and HSP70-2 polymorphisms in breast cancer: a case-control study

This case control study aims to investigate the role of HSP90 Gln488His (C > G), HSP70-2 P1/P2, HIF-1 alpha C1772T and HSPA8 intronic 1541-1542delGT polymorphisms as potential risk factors and/or prognostic markers for breast cancer. 113 consecutive incident cases of histologically confirmed ductal breast cancer and 124 healthy cases were recruited. The above mentioned polymorphisms were genotyped; multivariate logistic regression was performed. HSP90 GG (His/His) genotype was associated with elevated breast cancer risk. Similarly, the allele dose-response model pointed to increase in breast cancer risk per G allele. HSP70-2 P1/P2, HSPA8 intronic 1541-1542delGT and HIF-1 alpha polymorphisms were not associated with breast cancer risk, as evidenced by the dose-response allele models. The positive association between HSP90 G allele and breast cancer risk seemed to pertain to both premenopausal and postmenopausal women. With respect to survival analysis, none of the aforementioned polymorphisms was associated with either disease-free survival or overall survival. HSP90α Gln488His polymorphism seems to be a risk factor for breast cancer. On the other hand, our study did not point to excess risk conferred by HSPA8 1541-1542delGT, Hsp70-2 P1/P2 and HIF-1α C1772T.

Familial and large-scale case-control studies identify genes associated with nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy and has a remarkable geographic distribution, which is highly prevalent in southern China, Southeast Asia, and North Africa. Although most of the NPC are sporadic cases, the familial clustering of NPC has been demonstrated worldwide. Accumulating studies have proposed that the etiology of NPC is multi-stage and multi-factorial, involving genetic lesions, Epstein-Barr virus infection, and environmental exposure. Genetic variations result in differences in gene function, which in turn lead to different susceptibility to disease. Many studies have been carried out to dissect the genetic variants that contribute to NPC susceptibility. This article reviews the current progress of genetic studies to identify genes associated with NPC, focusing on the familial linkage and large-scale case-control study designs.

Genetic predisposition factors and nasopharyngeal carcinoma risk: a review of epidemiological association studies, 2000-2011: Rosetta Stone for NPC: genetics, viral infection, and other environmental factors

While infection with Epstein-Barr virus (EBV) is known to be an essential risk factor for the development of nasopharyngeal carcinoma (NPC), other co-factors including genetic factors are thought to play an important role. In this review, we summarize association studies conducted over the past decade to evaluate the role of genetic polymorphisms in NPC development. A review of the literature identified close to 100 studies, including 3 genome-wide association studies (GWAS), since 2000 that evaluated genetic polymorphisms and NPC risk in at least 100 NPC cases and 100 controls. Consistent evidence for associations were reported for a handful of genes, including immune-related HLA Class I genes, DNA repair gene RAD51L1, cell cycle control genes MDM2 and TP53, and cell adhesion/migration gene MMP2. However, for most of the genes evaluated, there was no effort to replicate findings and studies were largely modest in size, typically consisting of no more than a few hundred cases and controls. The small size of most studies, and the lack of attempts at replication have limited progress in understanding the genetics of NPC. Moving forward, if we are to advance our understanding of genetic factors involved in the development of NPC, and of the impact of gene-gene and gene-environment interations in the development of this disease, consortial efforts that pool across multiple, well-designed and coordinated efforts will most likely be required.

Variations in HSPA1B at 6p21.3 are associated with lung cancer risk and prognosis in Chinese populations

The heat shock protein Hsp70 is crucial for regulating cellular homeostasis in stressed cells. Although the tumorigenic potential and prognostic applications of Hsp70 have been widely investigated, it remains unclear whether genetic variations of the human isoforms HSPA1L, HSPA1A, and HSPA1B are associated with cancer risk and prognosis. In this study, we genotyped six tagSNPs in these genes in 1,152 paired patients with lung cancer and controls, and then validated the results in additional cohorts of 1,781 patients with lung cancer and 1,038 controls. In addition, we evaluated the associations of these tagSNPs with survival in 330 patients with advanced non-small cell lung cancer (NSCLC) with additional validation in another 331 patients with advanced NSCLC. Functions of the risk variants identified were investigated using cell-based reporter assays. We found that the HSPA1B rs6457452T allele was associated with increased lung cancer risk compared with the rs6457452C allele in both data sets and also pooled analysis (adjusted OR = 1.41; P = 2.8 × 10(-5)). The HSPA1B rs2763979TT genotype conferred poor survival outcomes for patients with advanced NSCLC in two independent cohorts and pooled analysis [adjusted hazard ratio (HR) = 1.80, 1.61, and 1.66; P = 0.013, 0.036, and 0.002, respectively]. Lastly, we also found that the rs2763979T and rs6457452T alleles were each sufficient to reduce expression of transcriptional reporter constructs, when compared with the rs2763979C and rs6457452C alleles, respectively. Taken together, our findings define that functional HSPA1B variants are associated with lung cancer risk and survival. These Hsp70 genetic variants may offer useful biomarkers to predict lung cancer risk and prognosis.

A functional tandem-repeats polymorphism in the downstream of TERT is associated with the risk of nasopharyngeal carcinoma in Chinese population

BACKGROUND

Increases in human telomerase reverse transcriptase (TERT) expression and telomerase activity are frequently seen in nasopharyngeal carcinoma (NPC). Recently, a variable tandem-repeats polymorphism, MNS16A, located in the downstream region of the TERT gene, was identified and reported to have an effect on TERT expression and telomerase activity. We examined whether the functional MNS16A was related to the risk of occurrence or progression of NPC in the Chinese population.

METHODS

We genotyped the MNS16A polymorphism in a case-control study of 855 patients with NPC and 1036 cancer-free controls using PCR, and determined genotype by classifying the DNA band of 243 or 272 base pairs (bp) as the short (S) allele and 302 or 333 bp as the long (L) allele. The genetic associations with the risk of NPC were analyzed by logistic regression.

RESULTS

The MNS16A genotype was not associated with the progression of NPC. However, individuals carrying the S alleles (SL + SS genotype) had a significantly reduced risk of NPC occurrence compared with those carrying the LL genotype (odds ratio (OR) = 0. 71, 95% confidence interval (CI) = 0. 52 to 0. 96, P = 0. 025). Using a immunohistochemical assay on the NPC tissues, the SL genotype carriers were found to have lower TERT expression than the LL genotype carriers (P = 0. 035).

CONCLUSIONS

Our study indicates that the TERT MNS16A polymorphism may contribute to the risk of NPC onset in Chinese population.

Polymorphic analysis of MHClinked Heat Shock Protein 70 genes: Their susceptibility and prognostic implication in Kangri cancer cases of Kashmiri population

Kangri cancer is a unique thermally-induced squamous cell carcinoma (SCC) of skin that develops due to persistent use of Kangri (a brazier), used by Kashmiri people, to combat the chilling cold during winter months. We designed a large scale case-control study to characterize the frequency of two polymorphisms within the MHC class III-linked HSP70genes, Hsp70-2 and Hsp70-hom, in order to find any association of these genotypic variants for predisposition to and clinical outcome of Kangri cancer patients from Kashmir valley in North India. Polymerase Chain Reaction and restriction enzymes were utilized to characterize the frequency of two polymorphisms with in Hsp70-2 and Hsp70-hom genes in 118 Kangri carcinoma cases and 95 healthy controls from the same population of Kashmir. Association of high frequency allelic variants of Hsp70genes with various clinicopathological features of prognostic significance was assessed by Chi-square test using SPSS software. In this study, allelic frequency of Hsp70-2 A/G heterozygote (0.87) (P = 0.012) was found to be significantly high in Kangri cancer cases compared to control (0.736) with a Relative Risk of 2.45 fold. Conversely, the allelic frequency of Hsp70-2 A/A allele in homozygous condition was significantly low in Kangri cancer cases and worked out to be 0.084 (Vs 0.252 in control) with P is equal to 0.001, implicating it as a protective allele against Kangri cancer in subjects with this genotype. Similarly, significantly high frequency of 0.50 (Vs 0.29 in control) of Hsp70-homC/C allele was found in homozygous condition in Kangri cancer cases suggestive of a positive relative risk associated with this genotype (RR is equal to 2.47) (P is equal to 0.002). The overall allele frequency data analysis of Hsp70-2 and Hsp70-hom genes was significant (χ² is equal to 12.38, P is equal to 0.002; and χ² is equal to 12.21, P is equal to 0.002). The study also reveals considerable association of high frequency alleles of HSP70 genes, especially of Hsp70-2 A/G or G/G in Kangri tumors with clinico-pathological features of poor prognosis. These results indicate that the relative risk of Kangri cancer associated with Hsp70-2 and Hsp70- hom gene polymorphisms is confined to Hsp70-2 A/G or G/G and Hsp70homC/C haplotype in our population. The study, therefore, suggests Hsp70-2 A/G or G/G and Hsp70homC/C genotypes as potential susceptibility markers and independent prognostic indicators in Kangri carcinoma patients in Kashmiri population.

Functional polymorphism -31C/G in the promoter of BIRC5 gene and risk of nasopharyngeal carcinoma among chinese

Background

Baculoviral inhibitor of apoptosis repeat-containing 5 (BIRC5, also called as survivin) is a member of the inhibitor of apoptosis protein (IAP) family, which plays an important role in the occurrence and progression of cancer. Recently, a polymorphism in the promoter of BIRC5, -31C/G (rs9904341), was shown to influence BIRC5 expression.

Methods

We examined whether the -31C/G was related to the risk of developing nasopharyngeal carcinoma (NPC) in a case-control population from Guangxi province in southern China, which consists of 855 patients with NPC and 1036 controls. This polymorphism was genotyped by TaqMan assay. The genetic associations with the occurrence and progression of NPC were estimated by logistic regression.

Results

We observed a statistically significant increased occurrence of NPC associated with the CC genotype (odds ratio [OR], 1.40; 95% confidence interval [CI], 1.13–1.73; P = 0.0020) compared with the genotypes containing G allele (CG + GG genotype). However, no significant association was observed for the -31C/G with the severity of NPC (as measured by tumor-node-metastasis staging system).

Conclusion

Our findings suggest that the functional polymorphism -31C/G in the promoter of BIRC5 gene may play a role in mediating the susceptibility to NPC among Chinese.

The relationship between three heat shock protein 70 gene polymorphisms and susceptibility to lung cancer

BACKGROUND

Heat shock protein 70 (Hsp70) has been shown to act as a chaperone and be associated with a variety of tumors. We investigated HSP70-1 G+190C, HSP70-2 A+1267G, and HSP70-hom T+2437C polymorphisms to assess whether genetic variation in HSP70 plays a role in the occurrence and development of lung cancer.

METHODS

A case-control study was conducted using 159 patients with lung cancer and 202 control subjects. Genomic DNA was typed for HSP70 polymorphisms using polymerase chain reactions with restriction fragment length polymorphism (PCR-RFLP). Unconditional logistic regression was used to estimate the relative risks of lung cancer.

RESULTS

There were significant differences in genotype and allele distributions between patients and controls for the HSP70-1 G+190C polymorphisms with and without adjustment for age, gender, smoking history, drinking history and family history of cancer (p<0.05). No significant differences were found in the polymorphisms of HSP70-2 A+1267G and HSP70-hom T+2437C. The haplotype analysis showed that the G/A/C and C/G/T haplotypes were associated with a significantly increased risk of lung cancer compared to the G/G/T haplotype. After adjustments for other risk factors, such as age, gender, drinking history and family history of cancer, the interactions between the HSP70-1 and HSP70-hom genotypes and smoking were confirmed [I(AB), 2.56 and 5.12, respectively].

CONCLUSIONS

HSP70-1 G+190C may be a functional polymorphism and affect susceptibility to lung cancer, and homozygous C/C genotype may enhance the risk of lung cancer. In addition, smoking along with HSP70-1 G+190C and HSP70-hom T+2437C, may increase the risk of lung cancer.

Polymorphisms in TNF and HSP-70 show a significant association with gastric cancer and duodenal ulcer

Tumour Necrosis Factor (TNF) and Heat Shock Protein 70 (HSP70) are important molecules in inflammatory, infectious and tumoral processes. The genes codifying these molecules are polymorphic and certain alleles have been associated with susceptibility to disease. Gastric cancer is associated with an Helicobacter pylori-induced chronic inflammatory response. The aim of this work was to analyze whether polymorphisms in inflammation-related genes are associated with the development of gastric cancer. We studied 447 Mexican adult patients including 228 with non-atrophic gastritis, 98 with intestinal metaplasia, 63 with gastric cancer and 58 with duodenal ulcer, and 132 asymptomatic individuals as well. DNA from peripheral white blood cells was typed for the Single Nucleotide Polymorphisms (SNPs) -308 of TNF-alpha, +252 of TNF-beta, +190 of HSP70-1, +1267 of HSP70-2 and +2437 of HSP70-HOM. Compared with the asymptomatic group, we found a significant association of TNF-beta*A and HSP70-1*C alleles with gastric cancer (OR 5.69 and 3.76, respectively) and HSP70-1*C with duodenal ulcer (OR 3.08). Genotype TNF-beta G/G showed a significant gene-dose effect with gastric cancer (OR 0.09); whereas HSP70-1 C/G showed significant association with both, gastric cancer (OR 13.31) and duodenal ulcer (OR 16.19). Polymorphisms in TNF and HSP70 showed a significant severity-dose-response as risk markers from preneoplastic lesions to gastric cancer in Mexican population, probably because of their association with an intense and sustained inflammatory response.

A protocol comparison for the analysis of heat shock protein A1B +A1538G SNP

Heat shock proteins act as molecular chaperones, assist in peptide maturation, and transport nascent peptides across membranes. One commonly studied single nucleotide polymorphism (SNP) for one of the proteins is HSPA1B (+A1538G). However, several studies of this polymorphism have failed to achieve Hardy-Weinberg equilibrium (HWE) for their sample. We compared various published procedures for analyzing the HSPA1B +A1538G SNP and report reasons for HWE discrepancies. Samples from 141 apparently healthy, physically active, volunteers (99 men and 42 women) were analyzed. The first protocol, initially described by Schröder et al., resulted in a genotypic distribution of 22 GG (15.6%), 119 AG (84.4%), and 0 AA; results were confirmed by reanalysis and sequencing. Two other published protocols, one described by Klausz et al. and another by Fekete et al., were used to confirm these results: both resulted in 22 GG (15.6%), 46 AA (32.6%), and 73 AG (51.7%). Additionally, the results were within HWE and confirmed by sequence analysis. Of the original 119 subjects genotyped as AG by the Schröder protocol, 46 of those were confirmed as AA with the Klausz and Fekete methods. Mixing primers from the Schröder and Klausz protocol resulted in 100% concordance with the data generated by the Klausz and Fekete protocols. Some published data on HSP genotyping deviate from HWE; thus, primers used for analyzing these highly homologous genes must be carefully considered. Our results highlight the importance of reinvestigating data when HWE is not achieved for the HSPA1B, or another, polymorphism.

HLA associations with nasopharyngeal carcinoma

Several associations have been described between the frequency of human leukocyte antigen (HLA) class I genes in certain populations and the risk of developing nasopharyngeal carcinoma (NPC). Associations between ethnic background and geographic distribution, and relative disease incidence have been reported. Populations in geographical areas at higher risk of developing NPC display HLA distribution patterns different and sometimes opposite from areas of low incidence, whereas populations in areas with intermediate incidence display a totally independent pattern. Two main reasons may explain this association between HLA phenotype distribution and the risk of developing NPC in various populations. First, given the fact that expression of Epstein-Barr Virus (EBV) proteins by cancer cells is tightly linked with NPC development, HLA may influence the development of NPC by modulating the expression of EBV proteins. This explanation is, however, based primarily on theoretical assumptions given that no clear definition of HLA binding pattern of EBV epitopes has been directly shown to significantly alter the recognition of EBV proteins and the risk of developing the disease. Alternatively, HLA may represent a genetic marker flagging the presence of a NPC predisposition locus in close linkage disequilibrium with the HLA class I region. A critical review of known HLA associations in various geographical areas and their interpretation will be presented in this review.

The human leukocyte antigen class I genes in nasopharyngeal carcinoma risk

Nasopharyngeal carcinoma (NPC) is a virally associated cancer which is highly prevalent in Southeast Asia and North Africa. Several linkage analysis studies suggested the association of susceptibility HLA (Human Leukocyte Antigen) alleles and haplotypes with NPC development. The HLA system is very polymorphic and according to the ethnic group studied, it has been found to have the capacity to confer susceptibility or resistance to NPC. Our aim was to review the most important described genetic associations of HLA class I in NPC and to comment on the inconsistent associations found in the different NPC incidence areas. We believe that the mechanisms of these associations may involve HLA genes through the differential capacity of each allele to present antigens. However, because HLA genes contain various linked candidate genes, HLA-NPC associations should be carefully interpreted.

Protective role of genetic polymorphism of heat shock protein 70-2 for gastric cancer risk

BACKGROUND

Heat shock protein 70-2 (HSP70-2) has a cytoprotective role in various conditions and also protects the gastric mucosa. Recently, polymorphism of HSP70-2 at position 1267 was suggested to be associated with carcinogenesis. We investigated the association of this polymorphism with the risk of gastric cancer in the present study.

METHODS

We examined 223 patients (159 men and 64 women, mean age 64.8 years) with gastric cancer who underwent gastrointestinal endoscopy at our department. The controls were 200 age-matched patients (140 men and 60 women) without gastric cancer diagnosed by gastrointestinal endoscopy. Genotyping was done by PCR-based restriction fragment length polymorphism analysis, and the PCR products were digested with PstI. The two allelic forms, corresponding to the presence or absence of the PstI site, were designated as the P1 allele and P2 allele, respectively. Logistic regression analysis was performed to calculate an odds ratios (ORs) for differences of HSP70-2 polymorphism between the two groups.

RESULTS

Among the 223 patients with gastric cancer, 46 (20.6%) had P1/P1, 177 (79.4%) were P1 carriers, and 6 (2.7%) were P2/P2. In the control group, 33 (16.5%) patients had P1/P1 polymorphism, 167 (83.5%) were P1 carriers, and 12 (6.0%) were P2/P2. The OR for gastric cancer of subjects with P2/P2 polymorphism relative to P1 carriers was 0.43 (95% CI = 0.16-1.17) (P = 0.097). Among females, the OR for gastric cancer of subjects with P2/P2 polymorphism relative to P1 carriers was 0.10 (95% CI = 0.012-0.838) (P = 0.014). This polymorphism was also associated with a lower risk of middle third cancer (OR = 0.13; 95% CI = 0.02-1.00).

CONCLUSIONS

P2/P2 polymorphism of HSP70-2 at position 1267 was associated with a lower risk of gastric cancer in females.

Association of MICA-129 polymorphism with nasopharyngeal cancer risk in a Tunisian population

Major histocompatibility complex (MHC) class I chain-related A (MICA) molecules mediate natural killer (NK) cell activation and T lymphocyte co-stimulation. A polymorphic methionine (met) to valine (val) variation at amino acid position 129 of the alpha2 heavy chain domain is in linkage disequilibrium with other allelic changes and seems to categorize MICA alleles into strong and weak binder of NKG2D receptor and thereby to influence effector cell function. We investigated here whether MICA-129 dimorphism is associated with susceptibility to/or resistance against developing nasopharyngeal cancer (NPC). DNA from 130 NPC patients and 180 healthy individuals from Tunisia were genotyped for MICA-129 variation. We found a higher frequency of MICA-129 val/val genotype in patients than in controls (corrected p value = 0.02) that could suggest a tumor escape mechanism because of failure to activate NK cells by MICA-129 val allele or absence of NK cell activation because of absence of MICA-129 met allele in individuals otherwise predisposed to viral/environmental factors.

HSP70s: From Tumor Transformation to Cancer Therapy

Heat shock proteins (HSPs) are a defined set of chaperones for maintaining proper functions of proteins. The HSP70 family, one of the most inducible families in response to stress, protects cells from stress-induced cell death. It has been documented that HSP70s are highly expressed in various types of cancer cells and make the cells resistant to adverse microenvironments, such as hypoxia and glucose starvation, which are common features in malignant progression. Over-expression of HSP70s is thus associated with tumor transformation and eventually results in a decrease of chemotherapy efficacy. Notably, the distribution of HSP70s is deregulated in cancer cells. It has been reported that HSP70s localize distinct organelles or are exported to humoral circulation during cancer development. Either surface or exported HSP70s play danger signals and trigger immune response to destroy the tumor cells. In this review, we lay out recent advances in the HSP70s-mediated cancer diagnosis and therapy. This review would be enlightening for clinical cancer medicine.

Heat shock protein A1B 1267 polymorphism is highly associated with risk and prognosis of hepatocellular carcinoma: a case-control study

We conducted a case-control study to elucidate the role of heat shock protein A1B (HSPA1B) 1267 single nucleotide polymorphism (SNP) on the risk and prognosis of hepatocellular carcinoma (HCC). Subjects enrolled included 150 pairs of sex- and age-matched HCC patients and unrelated controls. Genomic DNA was typed for HSPA1B1267 SNP using polymerase chain reaction with restriction fragment length polymorphism. The frequencies of the HSPA1B P2/P2 genotype and the HSPA1B P2 allele in HCC patients were higher than in unrelated controls (each p = 0.0001). Multivariate analysis identified the following independent risk factors for HCC: HSPA1B P1/P2 genotype (odds ratio [OR], 2.34; 95% confidence interval [CI], 1.07-5.11), HSPA1B P2/P2 genotype (OR, 12.06; 95% CI, 4.43-32.79), hepatitis B surface antigen (HBsAg) (OR, 25.95; 95% CI, 11.88-56.68), and antibodies to hepatitis C virus (anti-HCV) (OR, 70.43; 95% CI, 21.89-226.64). There was an additive interaction between HSPA1B P2 allele carriers and the presence of either HBsAg (synergy index = 2.48) or anti-HCV (synergy index = 1.52). However, as HSPA1B1267 SNP is a silent mutation, it is a surrogate genetic marker for increasing risk of HCC. Our findings indicate that patients with chronic hepatitis B/hepatitis C virus infection who harbor this SNP represent a high-risk group for HCC. They should receive more intensive surveillance for early detection of HCC. Moreover, patients with the HSPA1B P2 allele had significantly longer survival (p = 0.002).The limitations of this study include the unknown functional significance of the HSPA1B1267 polymorphism, the relatively small sample size, the fact that this was not a prospective study of cases and controls, and the questionable generalizability of the findings given the specific ethnic composition of the population studied.

Association between heat-shock protein 70 gene polymorphisms and DNA damage in peripheral blood lymphocytes among coke-oven workers

Hsp70 has been shown to act as a chaperone and be associated with cytoprotection against DNA damage caused by environmental stresses. However, it is unknown whether genetic variation in HSP70 plays a role in stress tolerance and cytoprotection against DNA damage. We determined the frequencies of three polymorphisms, HSP70-1 G190C, HSP70-2 G1267A, and HSP70-hom T2437C from 251 steel-plant workers exposed to coke-oven emission and 130 controls. We estimated the association between the HSP70variants/haplotypes and the levels of DNA damage in their peripheral blood lymphocytes detected by single-cell gel electrophoresis assay. Our results showed that overall coke-oven workers had higher levels of the Olive tail moment (Olive TM) (1.27+/-1.12) than that of the controls (0.56+/-0.99, P<0.001). Coke-oven workers with the HSP70-1 C/C genotype had higher levels of Olive TM (2.19+/-0.65), compared with HSP70-1 G/C and G/G carriers (Olive TM=1.34+/-1.09 and 1.14+/-1.08, respectively, P=0.022 and 0.003, respectively). However, the HSP70-2 G1267A and HSP70-hom T2437C polymorphisms were not associated with the levels of Olive TM (P=0.929 and 0.795, respectively). Haplotype analysis showed that carriers of TCG/TCG haplotype pairs had the highest levels of Olive TM among both the exposed subjects (2.04+/-0.59) and the controls (0.81+/-0.59). Our results suggest that the individuals with the homozygous HSP70-1 C/C genotype among the coke-oven workers may be susceptible to DNA damage.

Functional polymorphisms and haplotypes in the promoter of the MMP2 gene are associated with risk of nasopharyngeal carcinoma

Matrix metalloproteinases (MMPs) play important roles in cancer initiation and development. Several polymorphisms in the promoters of a number of MMP genes, which can affect the respective MMP production in an allele-specific manner, have been well characterized. We examined whether these functional polymorphisms were related to the risk of nasopharyngeal carcinoma (NPC) in Chinese populations. Eight polymorphisms in the promoter of MMP1, MMP2, MMP3, MMP7, MMP9, MMP12, and MMP13 were genotyped in two independent case-control populations; one is from Guangxi province (593 patients with NPC and 480 controls), and the other is from Guangdong province (239 patients and 286 controls). We observed significantly increased susceptibility to NPC for the MMP2 -1306CC (rs243865:C>T) (odds ratio [OR] = 2.01, 95% confidence interval [CI] = 1.30-3.10) and -735CC (rs2285053:C>T) (OR = 1.56, 95% CI = 1.17-2.09) genotype carriers compared with noncarriers in the Guangxi population. This association was confirmed in the Guangdong population (for -1306CC: OR = 2.19, 95% CI = 1.21-3.96; for -735CC: OR = 1.60, 95% CI = 1.13-2.28). The C(-1306)-C(-735) haplotype was also significantly associated with increased susceptibility to NPC in both the Guangxi (OR = 1.64, 95% CI = 1.35-1.99) and Guangdong population (OR = 1.68, 95% CI = 1.29-2.19). Furthermore, stratified analysis indicated that the increased susceptibility to NPC related to the -1306CC and -735CC genotype and the C(-1306)-C(-735) haplotype was more pronounced in heavier smokers. Our findings suggest that the genetic polymorphisms or haplotype in the MMP2 promoter may play a role in mediating the susceptibility to NPC in Chinese populations.

Genetic polymorphisms of TLR3 are associated with Nasopharyngeal carcinoma risk in Cantonese population

Background

Nasopharyngeal carcinoma is endemic in Southern China, displays a strong relationship with genetic susceptibility and associates with Epstein-Barr virus infection. Toll-like receptor 3 (TLR3) plays an important role in the antivirus response. Therefore, we examined the association between TLR3 gene polymorphisms and NPC susceptibility.

Methods

We performed a case-control study of 434 NPC cases and 512 healthy controls matched on age, sex and residence. Both cases and controls are of Cantonese origin from Southern China. Genetic variants in TLR3 were determined by polymerase chain reaction (PCR)-based DNA direct sequencing and four SNPs were genotyped in all samples.

Results

Our results showed that allele C for SNP 829A/C increased NPC risk significantly ((p = 0.0068, OR = 1.49, 95%CI:1.10–2.00). When adjusted for age, gender and VCA-IgA antibody titers, the NPC risk was reduced significantly among individuals who carried the haplotype "ATCT" compared to those who carried the most common haplotype "ACCT" (p = 0.0054, OR = 0.028; 95% CI (0.002–0.341).

Conclusion

The TLR3 polymorphisms may be relevant to NPC susceptibility in the Cantonese population, although the reduction in NPC risk is modest and the biological mechanism of the observed association merits further investigation.

Associations between HLA class I alleles and the prevalence of nasopharyngeal carcinoma (NPC) among Tunisians

The high prevalence of nasopharyngeal cancer (NPC) in Southern Asia and Mediterranean Northern Africa suggests genetic predisposition among other factors. While Human Leukocyte Antigen (HLA) haplotypes have been conclusively associated with NPC predisposition in Asians, Northern African Maghrebians have been less intensely studied. However, low resolution serological methods identified weak positive associations with HLA-B5, B13 and B18 and a negative with HLA-B14. Using sequence based typing (SBT), we performed a direct comparison of HLA class I frequencies in a cohort of 136 Tunisian patients with NPC matched for gender, age and geographical residence to 148 normal Tunisians. The bimodal age distribution of NPC in Maghrebians was also taken into account. HLA frequencies in normal Tunisians were also compared with those of Northern Moroccan Berbers (ME) to evaluate whether the Tunisian population in this study could be considered representative of other Maghrebian populations. HLA-B14 and -Cw08 were negatively associated with NPC (odd ratio = 0.09 and 0.18 respectively, Fisher p₂-value = 0.0001 and = 0.003). Moreover, positive associations were observed for HLA-B-18, -B51 (split of -B5) and -B57 (p₂-value < 0.025 in all) confirming previous findings in Maghrebs. The HLA-B14/Cw*08 haplotype frequency (HF) was 0.007 in NPC patients compared to 0.057 in both Tunisian (OR = 0.12; p₂-value = 0.001) and Moroccan controls. This study confirms several previous associations noted by serologic typing between HLA class I alleles and the prevalence of NPC in Maghrebians populations. In addition, we identified a putative haplotype rare in Tunisian patients with NPC that may serve as a genetic marker for further susceptibility studies.

MDM2 Promoter SNP309 Is Associated with Risk of Occurrence and Advanced Lymph Node Metastasis of Nasopharyngeal Carcinoma in Chinese Population

PURPOSE

Mouse double minute 2 (MDM2) is a key negative regulator of the p53 activity. Recently, a polymorphism in the MDM2 intronic promoter, SNP309, was shown to influence MDM2 expression and p53 activity. We examined whether the SNP309 was related to the risk of developing nasopharyngeal carcinoma (NPC) among Chinese populations.

EXPERIMENTAL DESIGN

We genotyped the SNP309 in two independent case-control populations in southern China, one is from Guangxi province (including 593 NPC patients and 480 controls) and the other is from Guangdong province (including 239 patients and 286 controls), by PCR direct sequencing. Multivariate logistic regression analysis was used to calculate adjusted odds ratio (OR) and 95% confidence interval (95% CI).

RESULTS

We observed that compared with the TT genotype, the genotypes containing G allele (GT + GG genotype) were associated with significant increased susceptibility to NPC in both Guangxi (OR, 1.43; 95% CI, 1.04-1.91) and Guangdong population (OR, 1.53; 95% CI, 1.00-2.36). When these two sample sets were combined, the OR of the GT + GG genotype developing NPC was 1.45 (95% CI, 1.12-1.85) compared with the TT genotype. Furthermore, compared with the TT genotype, the GT + GG genotype was also significantly associated with the advanced lymph node metastasis (OR, 1.84; 95% CI, 1.09-3.05).

CONCLUSIONS

Our findings suggest that the MDM2 SNP309 may be a risk factor for the occurrence and advanced neck lymph node metastasis of NPC in Chinese population.

TAP1 gene polymorphisms and nasopharyngeal carcinoma risk in a Tunisian population

To find out whether polymorphisms 333-Ile/Val and 637-Asp/Gly of the transporter part of the antigen processing 1 gene (TAP1) are associated with the development of nasopharyngeal carcinoma (NPC), we studied a total of 374 subjects (209 patients and 165 controls). We used the amplification refractory mutation system polymerase chain reaction (ARMS-PCR) method for analyzing the TAP1 gene polymorphisms. We found a significant difference between the patients and the controls in both the TAP1 codon 333 and codon 637 (P = 0.009 and P = 0.002, respectively). We also found that genotypes with the A allele were present in 206 patients with NPC and 155 controls (98.5 vs. 93.9%; P = 0.032; OR = 4.43) and that genotypes with the B allele were more often present in the control group (45 vs. 32%; P = 0.004; OR = 0.48), suggesting a significant positive association of the A allele with NPC risk and a protective role of the B allele. We have observed an association between the distribution of TAP1 alleles and the NPC patient's age at onset, compared with controls. These results back up the fact that the etiology of NPC in intermediate-risk countries is completely different in each peak of age prevalence and that each peak may possess its own particular oncogenic mechanism.

Expression Profiling Identifies Three Pathways Altered in Cellular Immortalization: Interferon, Cell Cycle, and Cytoskeleton

Abrogation of cellular senescence, resulting in immortalization, is a necessary step in the tumorigenic transformation of a cell. Four independent, spontaneously immortalized Li-Fraumeni syndrome (LFS) cell lines were used to analyze the gene expression changes that may have given these cell lines the growth advantage required to become immortal. A cellular senescence-like phenotype can be induced in immortal LFS cells by treating them with the DNA methyltransferase (DNMT) inhibitor 5-aza-deoxycytidine. We hypothesized, therefore, that genes epigenetically silenced by promoter methylation are potentially key regulators of senescence. We used microarrays to compare the epigenetic gene expression profiles of precrisis LFS cells with immortal LFS cells. Gene ontology analysis of the expression data revealed a statistically significant contribution of interferon pathway, cell cycle, and cytoskeletal genes in the process of immortalization. The identification of the genes and pathways regulating immortalization will lead to a better understanding of cellular immortalization and molecular targets in cancer and aging.

Evaluation of the associations between the single nucleotide polymorphisms of the promoter region of the tumor necrosis factor-alpha gene and nasopharyngeal carcinoma

BACKGROUND

Tumor necrosis factor-alpha (TNF-alpha) is a pro-inflammatory cytokine and may act as an endogenous tumor promoter. Single nucleotide polymorphisms (SNPs) of the TNF-alpha gene promoter region have been found to be associated with certain cancers. We conducted a case-control study to evaluate the association between these SNPs and nasopharyngeal carcinoma (NPC).

METHODS

We used polymerase chain reaction followed by restriction fragment length polymorphism analysis to determine the -308 TNF-alpha promoter genotypes of 89 NPC patients and 360 healthy controls. In 23 NPC patients and 50 controls, we determined the sequence from -1065 to -101 nucleotides of the TNF-alpha gene promoter region to detect SNPs.

RESULTS

In comparison with the controls, the NPC patients had higher proportions of men and carriage of IgA antibodies against the capsid antigen of Epstein-Barr virus, but had a similar carrier rate of the -308A allele (odds ratio [OR], 1.2; 95% confidence interval [CI], 0.7-2.0). The carriage of the -308A allele was not associated with the occurrence of NPC in comparison with -308G homozygosity. We also found no significant differences in the distributions of allelic variants of the -1031, -863, -857, and -806 loci of the TNF-alpha promoter region, but observed a lower carrier rate of the novel -806T allele in the NPC patients (OR, 0.3; 95% Cl, 0.0-2.9).

CONCLUSION

Allelic variants of the TNF-alpha promoter gene may not be used as biomarkers of susceptibility to NPC. The role of the -806T allele needs to be studied further.

Heat shock proteins in cancer: diagnostic, prognostic, predictive, and treatment implications

Heat shock proteins (Hsps) are overexpressed in a wide range of human cancers and are implicated in tumor cell proliferation, differentiation, invasion, metastasis, death, and recognition by the immune system. We review the current status of the role of Hsp expression in cancer with special emphasis on the clinical setting. Although Hsp levels are not informative at the diagnostic level, they are useful biomarkers for carcinogenesis in some tissues and signal the degree of differentiation and the aggressiveness of some cancers. In addition, the circulating levels of Hsp and anti-Hsp antibodies in cancer patients may be useful in tumor diagnosis. Furthermore, several Hsp are implicated with the prognosis of specific cancers, most notably Hsp27, whose expression is associated with poor prognosis in gastric, liver, and prostate carcinoma, and osteosarcomas, and Hsp70, which is correlated with poor prognosis in breast, endometrial, uterine cervical, and bladder carcinomas. Increased Hsp expression may also predict the response to some anticancer treatments. For example, Hsp27 and Hsp70 are implicated in resistance to chemotherapy in breast cancer, Hsp27 predicts a poor response to chemotherapy in leukemia patients, whereas Hsp70 expression predicts a better response to chemotherapy in osteosarcomas. Implication of Hsp in tumor progression and response to therapy has led to its successful targeting in therapy by 2 main strategies, including: (1) pharmacological modification of Hsp expression or molecular chaperone activity and (2) use of Hsps in anticancer vaccines, exploiting their ability to act as immunological adjuvants. In conclusion, the present times are of importance for the field of Hsps in cancer, with great contributions to both basic and clinical cancer research.

A functional variant in the transcriptional regulatory region of gene LOC344967 cosegregates with disease phenotype in familial nasopharyngeal carcinoma

Nasopharyngeal carcinoma is a common malignancy in Southeast Asian countries, and genetic background is a well-known component of the complexity underlying its tumorigenic process. We have mapped a nasopharyngeal carcinoma susceptibility locus to chromosome 4p15.1-q12 in a previous linkage study on nasopharyngeal carcinoma pedigrees. In this study provided in this communication, we screened all the genes in this region, with a focus on exons, promoters, and the exon-intron boundary to identify nasopharyngeal carcinoma-associated mutations or functional variants. Importantly, we found a novel gene (LOC344967) with a single nucleotide polymorphism -32G/A in the promoter region. This gene is a member of the acyl CoA thioesterase family that plays an important role in fatty acid metabolism and is involved in the progression of various types of tumors. The -32A variant was found cosegregated with the disease phenotype in the nasopharyngeal carcinoma pedigrees that we previously used for the linkage study. Moreover, this -32A variant creates an activator protein (AP-1)-binding site in the transcriptional regulatory region of LOC344967, which significantly enhanced the binding of AP-1 to the promoter region and the transcription activity of the promoter in vivo. Furthermore, the expression of LOC344967 was significantly up-regulated at both mRNA and protein levels in nasopharyngeal carcinoma cells sharing the -32G/A genotype compared with nasopharyngeal carcinoma cells with the -32G/G genotype. Collectively, these results provide evidence that the -32A variant is a functional sequence change and may be related to nasopharyngeal carcinoma susceptibility in the families studied.

Chromosomal imbalances in nasopharyngeal carcinoma: a meta-analysis of comparative genomic hybridization results

Nasopharyngeal carcinoma (NPC) is a highly prevalent disease in Southeast Asia and its prevalence is clearly affected by genetic background. Various theories have been suggested for its high incidence in this geographical region but to these days no conclusive explanation has been identified. Chromosomal imbalances identifiable through comparative genomic hybridization may shed some light on common genetic alterations that may be of relevance to the onset and progression of NPC. Review of the literature, however, reveals contradictory results among reported findings possibly related to factors associated with patient selection, stage of disease, differences in methodological details etc. To increase the power of the analysis and attempt to identify commonalities among the reported findings, we performed a meta-analysis of results described in NPC tissues based on chromosomal comparative genomic hybridization (CGH). This meta-analysis revealed consistent patters in chromosomal abnormalities that appeared to cluster in specific "hot spots" along the genome following a stage-dependent progression.

Les carcinomes du nasopharynx : de la biologie à la clinique

Nasopharyngeal carcinomas (NPC) are very different from other head and neck cancers because of their specific multifactorial etiology and their geographic distribution. Epstein-Barr Virus (EBV) is implicated in oncogenesis of NPC in association with genetic alterations such as inactivation of the p16/Ink4, p19/ARF, RASSF1 or Blu genes. Tumoral tissues include a very abundant characteristic lymphoid infiltrate. Inflammatory cytokines are produced by both malignant and infiltrating cells. There is no efficient immune response against the tumor. On the opposite, infiltrating lymphocytes might play a role in tumor development. Serological methods and detection of circulating viral DNA are expected to become useful for early detection of relapse and on a longer term for primary screening. NPC are often diagnosed at a late stage because patients may remain asymptomatic for a long time. Computed tomography (CT scan) and magnetic resonance imaging (MRI) are complementary for the initial evaluation. Positron emission tomography (PET) is efficient for the evaluation of treatment efficiency and detection of relapses. Treatment is based on radiotherapy and chemotherapy. Their optimal use needs to be evaluated by phase III trials but positive results have been obtained by concomitant association of radiotherapy and chemotherapy. Targeted therapies are being studied with strategies based on disruption of viral latency, use of replicative adenoviruses or anti-tumor vaccination.