Combined expression of HIF1α, VEGF and HER2 predicts metastasis, relapse and response to combination chemotherapy in colorectal cancer patients.

Addressing a single target is the frequent development of drug resistance followed by cancer relapse and treatment failure. Therefore, assessment of simultaneous expression of target molecules is essential to choose the optimal combination therapy for each colorectal cancer patient. This study aims to evaluate the immunohistochemical expression of HIF1α, HER2 and VEGF and to clarify their clinical significance as prognostic factors and predictive markers of FOLFOX (combination chemotherapy inclusive of Leucovorin calcium, Fluorouracil and Oxaliplatin response). Marker expression was retrospectively evaluated by immunohistochemistry in 111 patients with colorectal adenocarcinomas from south Tunisia, followed by statistical analysis. The immunohistochemical staining revealed that 45 %, 80.2 %, 86.5 % and 25.5 % of specimen were positive for nuclear, cytoplasmic HIF1α expression, VEGF and HER2 respectively. Nuclear HIF1α and VEGF were associated with worst prognosis while cytoplasmic HIF1α and HER2 were correlated with favourable prognosis. Multivariate analysis confirms the association between nuclear HIF1α, distant metastasis, relapse, FOLFOX response and 5 years overall survival. HIF1α positivity and HER2 negativity were significantly associated to short survival. Combined immunoprofiles HIF1α+/VEGF+, HIF1α+/HER2-, HIF1α+/VEGF+/HER2- were associated to distant metastasis, cancer relapse and short survival. Interestingly, our findings confirmed that patients bearing a HIF1α positive tumor were significantly more resistant to FOLFOX compared to negative ones (p = 0.002, p ≤ 0.001). Positive expression of HIF1α and VEGF, or decreased expression of HER2 was each associated with poor prognosis and short overall survival. In summary, we found that expression of nuclear HIF1α, alone or combined with VEGF and HER2 serves as a predictive marker of poor prognosis and FOLFOX response in colorectal cancer from south Tunisia.

Epstein-Barr virus in breast carcinoma and in triple negative cases impact on clinical outcomes.

BACKGROUND: The contribution of viral infection in tumors pathogenesis has currently attracted attention. Epstein-Barr virus is an infectious agent involved in numerous human malignancies, including breast cancer. Although, their prognostic impact in breast tumor is rarely investigated. Therefore, we sought in our study to evaluate the prevalence of EBV in Tunisian breast carcinoma and to examine their potential association with clinicopathological features and overall survival. METHODS: Our retrospective study included 100 formalin fixed paraffin embedded samples from Tunisian breast carcinoma. EBV infection was evaluated by immunohistochemical analysis, using monoclonal antibody against latent membrane protein 1 (LMP-1) and polymerase chain reaction. A subset of PCR positive specimens was subjected to in situ hybridization for the detection of EBER expression. Biomarker's expression was evaluated by immunohistochemistry method. Statistical analysis was also explored. RESULTS: The expression status of ER, PR and HER2 was 81%, 71.4% and 33.7% respectively. The triple negative profile was present in 10.84% of cases. LMP-1 expression was negative in all breast cancer specimens. PCR assay showed that 44% of patients were positive for EBV genome. None of the 15 PCR positive cases showed positive results for EBV by ISH. According to the molecular phenotype, there was a statistically significant difference in EBV DNA prevalence between breast cancer subgroups including TN (67%), Lum B (64%), HER2 + (50%) and Lum A (30%). Bivariate analysis showed that EBV DNA was significantly associated with HER2 + (p = 0.035), tumor size (p = 0.018) and high SBR grade (p = 0.009). Multiple logistic regression analysis confirms the positive correlation of EBV with tumor size (p = 0.048) and SBR grade (p = 0.042). Kaplan-Meier analysis showed that patients with EBV+ had significantly shorter overall survival than those with EBV- (p = 0.032). CONCLUSIONS: Our study demonstrated the presence of EBV DNA in Tunisian breast carcinoma. EBV DNA was associated with aggressive features and poor overall survival. Further investigations will be required in large samples size to clarify the potential role of EBV in breast tumor progression.

The Phytochemical and Pharmacological Properties of Citrus sinensis 'Maltese Half-blood' Essential Oil Peels Extracted and Optimized by Response-surface Methodology.

BACKGROUND: Citrus fruits have been a valuable economic crop for thousands of years. Furthermore, citrus essential oils are significant in the perfume, food, and beverage sectors, as well as aromatherapy and medical medicines. AIMS: The present study aims to evaluate the phytochemical and pharmacological potentials of the optimized Citrus sinensis 'Maltese half-blood' essential oils peels (CsEO) extraction yields using Response-Surface Methodology (RSM). OBJECTIVE: There have been few investigations on Citrus sinensis 'Maltese half-blood' essential oil. METHODS: Citrus sinensis 'Maltese half-blood' essential oil peels (CsEO) extraction yields were performed by hydro-distillation and optimized by using Response-Surface Methodology (RSM). The oils were analysed by GC-MS. Different chemical tests were used to evaluate antioxidant activities. The healing potential was evaluated using models' wounds on Wistar rats. RESULTS: The RSM optimization demonstrated the highest yield of CsEO of 6.89 g/100 g d.b. All three tested factors significantly influenced the CsEO extraction yield: washing saline solution concentration, washings number, and drying percentage of peels. Significant antioxidant activities were noted in CsEO: the DPPH assay reported an IC50 of 0.225 ± 0.014 mL/mg, the FRAP assay showed an IC50 of 0.235 ± 0.001, and the NO assay was an IC50 in order of 0.259 ± 0.019. CsEO was not genotoxic and considerably decreased the levels of DNA lesions induced by oxidants. Also, applying a cream with CsEO on wounds promotes significantly rapid wound healing. CONCLUSION: CsEO could be considered a rich natural source of antioxidants and bio-compounds to accelerate wound healing. It can be used in pharmaceutical sectors as an alternative to synthetic chemicals.

Punica granatum Peel and Leaf Extracts as Promising Strategies for HSV-1 Treatment.

Punica granatum is a rich source of bioactive compounds which exhibit various biological effects. In this study, pomegranate peel and leaf ethanolic crude extracts (PPE and PLE, respectively) were phytochemically characterized and screened for antioxidant, antimicrobial and antiviral activity. LC-PDA-ESI-MS analysis led to the identification of different compounds, including ellagitannins, flavonoids and phenolic acids. The low IC50 values, obtained by DPPH and FRAP assays, showed a noticeable antioxidant effect of PPE and PLE comparable to the reference standards. Both crude extracts and their main compounds (gallic acid, ellagic acid and punicalagin) were not toxic on Vero cells and exhibited a remarkable inhibitory effect on herpes simplex type 1 (HSV-1) viral plaques formation. Specifically, PPE inhibited HSV-1 adsorption to the cell surface more than PLE. Indeed, the viral DNA accumulation, the transcription of viral genes and the expression of viral proteins were significantly affected by PPE treatment. Amongst the compounds, punicalagin, which is abundant in PPE crude extract, inhibited HSV-1 replication, reducing viral DNA and transcripts accumulation, as well as proteins of all three phases of the viral replication cascade. In contrast, no antibacterial activity was detected. In conclusion, our findings indicate that Punica granatum peel and leaf extracts, especially punicalagin, could be a promising therapeutic candidate against HSV-1.

Prognostic value of combining E-cadherin, p53, Bcl-2 and Bcl-xL expression and survival in Tunisian colorectal adenocarcinoma patients.

Colorectal cancer (CRC) is a common health issue worldwide with an extremely low survival rate after relapse. This study aims to evaluate the immunohistochemical expression of p53, E-cadherin, Bcl-2 and Bcl-xL and find a potential correlation between these markers, clinicopathological factors and overall survival of colorectal cancer patients. Marker expression was immunohistochemically determined in 105 patients with colorectal adenocarcinoma from southern Tunisia, followed by statistical analysis. Positivity rate of nuclear p53, membranous E-cadherin and cytoplasmic Bcl-2 - Bcl-xL was 85.71%, 76.47%, 59.8%, and 85.71% respectively. Spearman correlation showed that p53 was significantly and positively related to E-cadherin, Bcl-2, Bcl-xL and distant metastasis. A positive significant correlation between E-cadherin and anti-apoptotic proteins was also seen. Membranous E-cadherin expression was significantly and negatively associated to poor prognosis factors including lymph node metastasis, lymph invasion, venous invasion and distant metastasis. Bcl-2 expression was significantly correlated to distant metastasis. Multivariate analysis showed a significant association between dependent variable E-cadherin and covariates including differentiation, lymph invasion, venous invasion, distant metastasis, Bcl-2 and Bcl-xL. Poor 3-years OS and 5-years OS were significantly related to p53, Bcl-2 expression and E-cadherin loss. Positive E-cadherin combined with negative p53 and Bcl-2 as well as double-positive for E-cadherin and Bcl-xL were associated to best overall survival. Although each protein can be an independent prognostic factor, Simultaneous E-cadherin, p53, Bcl-2, Bcl-xL expression could be a crucial prognostic and overall survival marker to CRC patients. Multivariate analysis confirmed a positive correlation between membranous E-cadherin loss and colorectal cancer severity.

Role of biochar in anaerobic microbiome enrichment and methane production enhancement during olive mill wastewater biomethanization.

The current research work attempted to investigate, for the first time, the impact of biochar addition, on anaerobic digestion of olive mill wastewater with different initial chemical oxygen demand loads in batch cultures (10 g/L, 15 g/L, and 20 g/L). Methane yields were compared by applying one-way analysis of variance (ANOVA) followed by post-hoc Tukey's analysis. The results demonstrated that adding at 5 g/L biochar to olive mill wastewater with an initial chemical oxygen demand load of 20 g/L increased methane yield by 97.8% and mitigated volatile fatty acid accumulation compared to the control batch. According to the results of microbial community succession revealed by the Illumina amplicon sequencing, biochar supplementation significantly increased diversity of the microbial community and improved the abundance of potential genera involved in direct interspecies electron transfer, including Methanothrix and Methanosarcina. Consequently, biochar can be a promising alternative in terms of the recovery of metabolic activity during anaerobic digestion of olive mill wastewater at a large scale.

Intensification of Biophenols Extraction Yield from Olive Pomace Using Innovative Green Technologies.

Olive pomace is the main by-product generated by the olive oil production process. Although toxic to the environment, olive pomace is an important source of natural antioxidants due to its high content of phenolic compounds. The aim of the current study is to maximize the extraction yields of the main phenolic compounds present in olive pomace using innovative green technologies. For this purpose, the present work is divided into two parts. The first part is based on a solubility study of targeted phenolic compounds in various ethanol/water ratios at two different temperatures (20 °C and 50 °C). A computational prediction using COSMO-RS software was applied for the calculation of eventual solubility, which was subsequently confirmed by practical experiments. The determination of the optimal extraction conditions of solvent ratio (EtOH/H2O) (60:40 v/v) and temperature (50 °C) led to the second part of the work, which concerns the intensification of extraction yields. Furthermore, various green extractions using innovative technologies, including accelerated solvent extraction (ASE), ultrasound with its both system (probe (UAE-P) and bath (UAE-B)), bead milling (BM) and microwave (MAE), were carried out and then compared to conventional maceration (CM). Results showed that ASE was the most effective method for extracting phenolic compounds from dried olive pomace powder (5.3 milligrams of tyrosol equivalent (TE) per gram of dried olive pomace powder (DOP)) compared to CM (3.8 mg TE/g DOP).

In Vitro Anti-Epstein Barr Virus Activity of Olea europaea L. Leaf Extracts.

Olea europaea L. var. sativa (OESA) preparations are widely used in traditional medicine in the Mediterranean region to prevent and treat different diseases. In this research, olive extracts derived from the leaves of the OESA tree have been screened for antioxidant activity by two methods: the DPPH free radical scavenging assay (DPPH) and the Ferric reducing antioxidant power (FRAP) assay. The DPPH assay showed that OESA possesses a stronger antioxidant activity (84%) at 1 mg/mL while the FRAP method showed a strong metal ion chelating activity (90%) at 1 mg/mL. The low IC50 values, obtained by two different methods, implies that OESA has a noticeable effect on scavenging free radicals comparable to standards. During EBV infection, the free radicals increased triggering lipid oxidation. Therefore, the monitoring of the secondary lipid peroxidation products was done by measuring malonaldehyde (MDA) and conjugated dienes (DC). The simultaneous treatment of Raji cells with OESA and TPA, as an inductorof the lytic cycle, generated a significant decrease in MDA levels and DC (p < 0.05). Besides, Raji cells simultaneously exposed to TPA and OESA exhibited a percentage of EBV-positive fluorescence cells lower than TPA treated cells (**** p < 0.0001). This suggests that OESA treatment has a protective effect against EBV lytic cycle induction.

Impact of cathepsin D activity and C224T polymorphism (rs17571) on chronic obstructive pulmonary disease: correlations with oxidative and inflammatory markers.

BACKGROUND: Cathepsin D (CTSD) is an aspartyl proteinase that plays an important role in protein degradation, antigen processing and apoptosis. It has been associated with several pathologies such as cancer, Alzheimer's disease and inflammatory disorders. Its function in lung diseases remains, however, controversial. In the current study, we determined CTSD activity in serum of patients with chronic obstructive pulmonary disease (COPD) and evaluated the correlations between this proteinase and inflammatory and oxidative parameters. We also investigated the impact of a CTSD C224T polymorphism on enzyme activity and clinicopathological parameters. METHODS: Our population included 211 healthy controls and 138 patients with COPD. CTSD activity, MMPs (-1/-7/-12), cytokines (IL-6, TNF-α), malondialdehyde (MDA), nitric oxide and peroxynitrite levels were measured in patients and controls using standard methods. Genotyping of CTSD C224T polymorphism was determined using PCR-RFLP. RESULTS: Our results showed an increased CTSD activity in COPD patients compared to healthy controls (4.87 [3.99-6.07] vs. 3.94 [2.91-5.84], respectively, p < 0.001). COPD smokers presented also a higher CTSD activity when compared to nonsmokers (4.91[3.98-6.18] vs. 4.65[4.16-5.82], respectively, p = 0.01), while no differences were found when subjects were compared according to their GOLD stages. The activity of this proteinase was not dependent on the C224T polymorphism because we did not found any influence of this SNP on proteinase activity among patients and controls. Furthermore, our data provide the first evidence of the interrelationships between CTSD activity and both MMPs and TNF-α levels (MMP-1[r = - 0.4; p = 0.02], MMP-7[r = 0.37; p = 0.04], MMP-12[r = 0.43; p = 0.02], TNF-α [r = 0.89, p = 0.001]) in COPD smokers. There were no correlations, however, between CTSD activity and oxidative stress parameters in controls and patients. CONCLUSION: Our findings suggest that CTSD could be a relevant marker for COPD disease. Alteration of CTSD activity may be related to increased MMPs and TNF-α levels, particularly in COPD smokers.

Lawsonia inermis essential oil: extraction optimization by RSM, antioxidant activity, lipid peroxydation and antiproliferative effects.

BACKGROUND: The present study was focused on the optimization of yield of the essential oil extraction from leaves of Lawsonia inermis, and the determination of chemical composition, antioxidant activities, and lipid peroxydation and antiproliferative effects. METHODS: Henna essential oil (HeEO) were extracted by hydrodistillation; the identification of the chemical composition were done by GC/MS method. HeEO was analyzed for antioxidant power in: (1) chemical system by the DPPH test, the ABTS test and the total antioxidant activity test; and (2) in biological system by lipid peroxydation tests (MDA and DC) in cells culture. The cytotoxicity effects of HeEO were assessed using MTT assay against Raji and HeLa cell lines. RESULTS: The optimal extraction yield was 6.8 g/100 g d.b. HeEO showed a remarkable anti-oxidant activities including DDPH (42%), ABTS (87%) and the power of ammonium phosphomolybdate (2992 ± 230 mg of HeEO by equivalent to 1 mg of vitamin C in terms of total antioxidant power). CONCLUSION: Beyond notable antioxidant activities of the HeEo, our results showed a significant decrease in the production of ERO in the Raji cell line. The anti-tumor power of the Henna essential oil shows an interesting cytotoxicity effect (IC50 at 0.26 µg/mL for Raji and at 1.43 µg/mL for HeLa) with a total mortality percentage reaching 60%, for both.

Optimization of Cinnamon (Cinnamomum zeylanicum Blume) Essential Oil Extraction: Evaluation of Antioxidant and Antiproliferative Effects.

Having high cytotoxicity cell line effect, Cinnamomum zeylanicum Blume essential oil offers a novel approach to the chemotherapy treatment. In order to enhance its quantity/purity, the experimental conditions to produce essential oil should be more exploited. Steam distillation was used to isolate essential oil, and its conditions' optimization was carried out with the surface-response methodology. The maximum amount (2.6 g/100 g d.b.) was obtained under minimum condensation water flow (0.8 mL/min), a sample size of 6.5 cm, a saline solution concentration of 262.5 g/L, and five washings. The produced essential oil contains >77% of polyphenols. In vitro cytotoxicity was examined using an MTT assay against HeLa and Raji cell lines. The essential oil's capability to inhibit the proliferation of HeLa and Raji cell lines was studied under some conditions presenting IC50 values of 0.13 and 0.57 µg/mL, respectively. The essential oil was evaluated for its potential as an antioxidant by using in vitro models, such as phosphomolybdenum, DPPH, and H2O2 methods, in comparison with the synthetic antioxidant BHT (butylated hydroxytoluene) and ascorbic acid (vitamin C) as positive controls. The ammonium phosphomolybdate potency in the present study is of the order of 108.75 ± 32.63 mg of essential oil/equivalent to 1 mg of vitamin C in terms of antioxidant power, and the antioxidant activity of DPPH-H2O2 was 21.3% and 55.2%, respectively. The Cinnamomum zeylanicum Blume essential oil (CEO) covers important antioxidant and antiproliferative effects. This can be attributed to the presence of few minor and major phenolic compounds.

Does supplemental zeolite (clinoptilolite) affect growth performance, meat texture, oxidative stress and production of polyunsaturated fatty acid of Turkey poults?

BACKGROUND: Following the ban on the use of growth factors, the use of zeolite in poultry feed could be a solution to obtain healthier food products that are more demanded by the consumer. METHODS: Zeolite (Clinoptilolite) was added to turkey male and female feed at concentrations 1% or 2% and was evaluated for its effectiveness on performance of the production. The turkeys were given free and continuous access to a nutritionally non-limiting diet (in meal form) that was either a basal diet or a 'Zeolite supplemented-diet' (the basal diet supplemented with clinoptilolite at a level of 1% or 2%). RESULTS: It was found that adding zeolite in the turkey diet had a positive effect on growth performance and increased weight gain compared to the control. In addition, zeolite treatment had a positive effect on oxidative stress and organoleptic parameters that were measured. It was found that adding zeolite in the turkey diet reduced the MDA level in the liver and in the meat, as compared to the control. Quality of meat was measured as a significantly increase (p < 0.05) in pH for male meat, indicated that the zeolite could maintain the quality of longer period. The adding of zeolite in the turkey diet increased level of polyunsaturated fatty acid. CONCLUSION: This study showed the significance of using zeolite, as a feed additive for turkey, as part of a comprehensive program to improve growth performance and oxidative stress parameters and to increase level of polyunsaturated fatty acid on the turkey body.

DNA repair gene polymorphisms and risk of head and neck cancer in the Tunisian population.

Altered activity of DNA repair enzymes may be involved in modulating cancer susceptibility and pathogenesis of head and neck cancer (HNC). We conducted a case-control study to test the association between three common single-nucleotide polymorphisms of XRCC1, ERCC2, and ERCC3 genes with HNC risk in Tunisian patients. To the best of our knowle dge, this is the first report on polymorphisms in XRCC1, ERCC2, and ERCC3 and susceptibility to HNC in our population. The genotype analyses of XRCC1 Arg399Gln, ERCC2 Lys751Gln, and ERCC3 7122 A>G polymorphisms for 169 HNC patients, and 261 controls were performed using the PCR-based restriction fragment length polymorphism. Stratification of the populations according to smoking and drinking habits and occupational exposure highlighted the importance of tobacco, alcohol, and toxic substance as three risk co-factors for the development of HNC. Our study suggests that only the XRCC1 Arg399Gln polymorphism was associated with the risk of HNC in the Tunisian population (OR = 2.04; P = 0.001). Furthermore, the risk of HNC was associated with XRCC1 Arg399Gln polymorphism stratified by occupational exposure status (OR = 2.29; P = 0.024). However, no statistically significant association was observed between the risk of developing HNC and the ERCC2 Lys751Gln and ERCC3 A>G polymorphisms. These data suggest that the XRCC1 Arg399Gln polymorphism is associated with an increased risk of developing HNC, because it correlates with occupational exposure in Tunisian population.

Genetic features of thyroid hormone receptors.

Thyroid hormone receptors (TR) are prototypes of nuclear transcription factors that regulate the expression of target genes. These receptors play an important role in many physiological processes. Moreover, a dysfunction of these proteins is often implicated in several human diseases and malignancies. Here we report genetic variations and alterations of the TRs that have been described in the literature as well as their potential role in the development of some human diseases including cancers. The functional effects of some mutations and polymorphisms in TRs on disease susceptibility, especially on cancer risk, are now established. Therefore, further investigations are needed in order to use these receptors as therapeutic targets or as biological markers to decide on appropriate forms of treatment.

Mutations and polymorphisms of estrogens receptors genes and diseases susceptibility.

BACKGROUND: Estrogen receptors (ER) belong to the super-family of the nuclear hormone receptors which act as ligand-regulated transcription factor to control a diverse set of essentials functions, such as growth development, metabolism, and reproduction. Though, the involvement of these receptors in several diseases including cancer was shown in numerous studies. AIM: Here, we reviewed the literature to report genetic polymorphisms and mutations investigated in the ESR genes (α and ß) and to explore their relationship and their potential role to develop some diseases as well as the ER expression status especially in cancer. METHODS: We searched the MEDLINE database with the keywords of estrogens receptors gene polymorphisms, short tandem repeat (STR) sequences, single-nucleotide polymorphisms (SNPs), cancer risk and diseases susceptibility. RESULTS: The functional effects of some mutations, short nucleotide polymorphisms and STR polymorphisms of ESR gene on susceptibility of multiple diseases, especially on cancer risk, are well approved. CONCLUSIONS: The involvement of genetic variations of the ERs in the risk of multiples diseases is frequently established, which incite to more elucidate the functional role of these markers in cell. Therefore, further investigations are needed to see the impact of these variations in drug response which makes them suitable therapeutic.

EGFR overexpression relates to triple negative profile and poor prognosis in breast cancer patients in Tunisia.

BACKGROUND: The prognosis of breast carcinoma is related to a large variety of clinical and pathological factors. Currently, only oestrogen (ER) and progesterone (PR) receptors and human epidermal growth factor receptor 2 (HER2) are used in routine pathological assessment as biomarkers. The aim of this study was to evaluate the prognostic impact of epidermal growth factor receptor (EGFR) expression individually and in combination to classical biomarkers (HER2, ER, and PR), and its relation to tumors with triple negative profile in Tunisian breast carcinoma. METHODS: Immunohistochemistry was used to estimate the rate expression of these receptors. Univariate and multivariate analyses were used to explore the prognostic significance of EGFR in this study. RESULTS: The expression rate of EGFR was 28.6%. EGFR expression was inversely correlated to that of ER (P < 0.001). Significant correlations between the expression of EGFR and the high histological Scarff-Bloom-Richardson (SBR) grade (P = 0.038) and also with tumors size (P = 0.041) were observed. The triple negative profile (TN: ER-/PR-/HER2-) was present in 17.3% of cases. EGFR overexpression was positively associated with this clinical aggressive profile (P < 0.001). Survival analysis showed that EGFR expression was associated with poor survival of patients (P = 0.004). In multivariate analysis, EGFR expression (P = 0.035) was found to be independent prognostic factors (significantly correlated to survival). CONCLUSION: EGFR overexpression was observed in 28.6% of Tunisian breast carcinoma, associated with unfavorable prognosis and with triple negative tumors. Systemically evaluation of EGFR in breast carcinoma could benefit especially to TN subgroup from EGFR targeting agents.

HER2 polymorphisms and breast cancer in Tunisian women.

HER2 has been thought to play a critical role in both breast cancer development and progression. Any functional polymorphisms can potentially affect breast cancer risk as well as cancer phenotype and outcome. In our study, we analyzed three polymorphisms in the HER2 gene: the single-nucleotide polymorphism (SNP) HER2 Ile(655)Val as well as another SNP (rs903506) close to it and a new screened dinucleotide repeat H(AC)I4 in intron 4, in a sample of 148 cases and 290 controls from the Tunisian population and investigated their association with breast cancer risk. For the HER2 Ile(655)Val, we found similar allele frequencies between cases and controls (frequency of I allele was 0.92 and 0.91, respectively). The same was observed for the noncoding SNP (rs903506). These two SNPs also showed no association with any clinical parameters, except the association of HER2 Ile(655)Val with tumor size (p = 0.002). But, a significant association was found between the short tandem repeat (STR) [H(AC)I4] and breast cancer risk at both genotypic and allelic levels (p = 0.0004 and p = 0.0001, respectively). Multivariate analysis with binary logistic regression of disease status on genotypes of the three polymorphisms confirmed the association of STR with breast cancer risk (p = 0.016). Therefore, this STR seems to be a promising biomarker in breast cancer and deserves further investigation.

Association of EGFR and HER2 polymorphisms with risk and clinical features of thyroid cancer.

The epidermal growth factor receptor family plays a critical role in the control of many physiological processes. Genetic alterations and/or variations in the gene encoding these receptors have been implicated in a variety of human cancers. In this study we evaluate the association of two single-nucleotide polymorphisms (SNP), R497K and I655V, of the EGFR and HER2 genes, respectively, with thyroid cancer risk. The analysis was performed with 302 healthy individuals and 106 thyroid cancer patients. No significant difference was found in the allelic and genotypic frequency distribution of the SNP R497K between the control and patient groups. While for the SNP I655V, the allele G is more frequent in patients than in controls and was associated with an increased risk of thyroid cancer (odds ratio = 1.88; 95% confidence intervals: 1.18-3.01; p = 0.007). We have also investigated the relationship between these two polymorphic sites and clinicopathological characteristics such as thyroid-stimulating hormone level, off-thyroxin, serum thyroglobulin, tumor histology, metastasis, tumor status, tumor stage, and survival. No significant association was observed. Tumor status was found significantly associated with HER2 I655V as well as with two previously studied markers in the thyroid hormone receptor A and estrogen receptor 1 (ESR1) genes (D17S2189 and D6S440, respectively). We also report a correlation between thyroglobulin level and genotypes for SNP rs2228480 in exon 8 of the ESR1 gene. In conclusion, our results suggest that the SNP HER2 I655V, but not the EGFR R497K, was associated with thyroid cancer risk.

Genetic polymorphisms in the EGFR (R521K) and estrogen receptor (T594T) genes, EGFR and ErbB-2 protein expression, and breast cancer risk in Tunisia.

We evaluated the association of epidermal growth factor receptor (EGFR) 142285G>A (R521K) and estrogen receptor alpha (ESR1) 2014G>A (T594T) single nucleotide polymorphisms with breast cancer risk and prognosis in Tunisian patients. EGFR 142285G>A and ESR1 2014G>A were genotyped in a sample of 148 Tunisian breast cancer patients and 303 controls using PCR-RFLP method. Immunohistochemitsry was used to evaluate the expression levels of EGFR, HER2, ESR1, progesterone receptor and BCL2 in tumors. We found no evidence for an association between EGFR R521K polymorphism and breast cancer risk. However, we found that the homozygous GG (Arg) genotype was more prevalent in patients with lymph node metastasis (P = .03) and high grade tumors (P = .011). The ESR1 2014G allele showed significant association with breast cancer risk (P = .025). The GG genotype was associated with HER2 overexpression and this association withstood univariate and multivariate analyses (P = .009; P = .021, resp.). These data suggest that the R521K might be a prognostic factor, because it correlates with both tumor grade and nodule status. The higher expression of HER2 in ESR1 T594T GG patients suggests the possibility that ESR1 gene polymorphisms accompanied by HER2 expression might influence the pathogenesis of breast cancers.