Shedding light on the EpCAM: An overview.

The epithelial cell adhesion molecule (EpCAM) is a Type I transmembrane superficial glycoprotein antigen that is expressed on the surface of basolateral membrane of multiple epithelial cells with some exceptions such as epidermal keratinocytes, hepatocytes, thymic cortical epithelial cells, squamous stratified epithelial cells, and myoepithelial cells that do not express the molecule. The molecule plays a pivotal role in the structural integrity, adhesion of the epithelial tissues and their interaction with the underlying layers. EpCAM prevents claudin-7 and claudin-1 molecules from degradation, thereby, decreasing the number of tight junctions and cellular interconnections, and promoting the cells toward carcinogenic transformation. Moreover, the mutations in the EpCAM gene lead to congenital tufting enteropathy, severe intestinal epithelium homeostasis disorders, and Lynch and Lynch syndrome. Overexpression of EpCAM on stem cells of some cancers and the presence of this molecule on circulating tumor cells (CTCs) makes it a promising candidate for cancer diagnosis as well as tracing and isolation of CTCs.

Detection and molecular characterization of bovine leukemia virus in various regions of Iran.

Purpose. Bovine leukemia virus (BLV) infects cattle worldwide, imposing an economic impact on the dairy cattle industry. The purpose of this study was to evaluate the molecular epidemiology of BLV in Iran.Methodology. Blood samples taken from 280 cows aged over 2 years old from 13 provinces of Iran were used for leukocyte count and blocking ELISA. Genomic DNA was extracted from the peripheral blood leukocytes of BLV-infected samples and fetal lamb kidney cells to perform PCR of partial env, rex and tax genes and long-terminal-repeat region. The PCR products were sequenced, the phylogenetic tree of each gene was constructed, and nucleotide and amino acid sequence pair distances were calculated.Results. The frequency of BLV infection was 32.8 % among animals and was 80 % among provinces. In BLV seropositive animals, the rate of persistent lymphocytosis was 36.9 %. The constructed phylogenetic trees showed the presence of two BLV genotypes (1 and 4) in Iranian strains. As previous studies, our results showed that the env gene was more variable than previously thought, the Rex protein could withstand more amino acid changes compared to the Tax protein, and no significant differences were observed in average changes of the nucleotide of these genes between clinical stages.Conclusions. Our data indicates an increase in the frequency of this infection in Iran. This is the first study report of the presence of BLV genotype 4 in Iranian farms. These findings may have an important role in the control and prevention of BLV infection in Iran and other countries.

Seroprevalence, molecular epidemiology and quantitation of parvovirus B19 DNA levels in Iranian blood donors.

Human parvovirus B19 (B19) infection is common among blood donors, and healthy blood donors can transmit virus via transfusion. Due to resistance of B19 to viral inactivation methods, there is a potential concern regarding transfusion safety in blood products. We aimed to determine the seroprevalence, molecular epidemiology, and quantitation of B19 DNA levels in blood donors in Tehran, Iran. A total of 500 blood donors from Blood Transfusion Research Center were studied. ELISA was used for detection of B19 IgG and IgM and nested PCR was carried out for detection of B19 DNA. PCR products were subjected to direct sequencing. B19 viral load was determined by real time PCR. B19 IgG, IgM, and DNA were detected in 27.6, 2.6, and 1.2% of donors respectively. Ten samples (2%) were positive for both antibodies while in four cases (0.8%), B19 IgG and DNA detected simultaneously. One case had B19 IgM, IgG, and viremia concurrently. The titers of B19 DNA in four of six donors were more than 106 IU/mL (high level viremia) and all four cases had IgG simultaneously. All B19 isolates categorized in genotype 1A. Our findings indicated that prevalence of B19 DNA in Iranian blood donors was comparable with previous studies throughout the world. High level B19 viremia found in 0.8% of our donors and all viremic donors revealed neutralizing B19 antibody. Therefore implementation of a B19 screening test for each volunteer blood donor does not appear to be necessary but B19 testing for plasma-derived products seems important in Iranian donors.

Frequency and subtype of BK virus infection in Iranian patients infected with HIV.

Human polyomavirus BK virus (BKV) is a double-stranded DNA virus that infects approximately 90 % of the general population as a subclinical or mild infection. In immunosuppressed patients, such as HIV cases, BKV may be reactivated resulting hemorrhagic cystitis and tubulointerstitial nephritis. However, there are limited studies on prevalence and molecular epidemiology of BKV in Iran. We therefore aimed to evaluate the prevalence and subtypes of BKV in Iranian HIV patients. A total of 99 patients with HIV infection were enrolled in the study. Presence of BKV DNA in plasma was evaluated by nested PCR. PCR products were sequenced directly, and phylogenetic analysis was performed. BKV DNA was detected in 8.08 % of HIV patients. BKV viremia presented in 4 out of 25 patients (16 %) not receiving antiretroviral therapy in comparison with 4 out 74 of HAART-treated patients (5.4 %) (P = 0.023). In patients with CD4 counts ≥200 cells/mm(3), viremia was found more commonly (7/80 = 8.8 %) than in those with lower counts (1/19 = 5.2 %) (not significant). All sequenced BKV isolates belonged to subtype Ib-2. Our findings indicated that the prevalence of BKV viremia is relatively prevalent in patients with HIV infection and significantly higher in naïve than HAART-treated cases. Therefore, HAART can eliminate BKV infection from plasma and reduce viremia although the actual implication of BKV viremia in HIV patients is not clear.

Frequency and Genotype of Human Parvovirus B19 among Iranian Hemodialysis and Peritoneal Dialysis Patients.

OBJECTIVES: The aim of this study was to evaluate the frequency and genotype of human parvovirus B19 and its relation with anemia among Iranian patients under dialysis. METHODS: Fifty hemodialysis (HD) and 33 peritoneal dialysis (PD) patients were enrolled. B19 IgG and IgM antibodies were assessed by ELISA, and the presence of B19 DNA was evaluated by nested PCR. PCR products were sequenced directly and phylogenetic analysis was performed. RESULTS: In the HD group, the prevalence of B19 antibodies was 54% for IgG and 4% for IgM. B19 DNA was detected in 10% of the cases, and 10% showed B19 IgG and viremia simultaneously. In the PD group, the prevalence of B19 IgG and IgM was 57.6 and 0% respectively, whereas B19 DNA was found in 12.1% of the group. A total of 9.1% showed B19 IgG and viremia concurrently. There was no significant difference regarding anemia and B19 infection in either group. All B19 isolates were clustered in genotype 1A. CONCLUSION: Our findings indicate that B19 infection plays no role in leading chronic anemia in dialysis patients. However, persistent B19 viremia and the circulation of the same strains in dialysis patients may indicate a potential risk for the contamination of dialysis equipment and nosocomial spread of B19 infection within dialysis units.

No evidence of persistent parvovirus B19 viremia among Iranian patients with HIV after a 1-year follow-up.

Recent studies have demonstrated that, in common with other latent viruses, parvovirus B19 infection can be controlled by the host immune response but may persist in some places such as the bone marrow. Persistent B19 infection has been found in both immunocompetent and immunocompromised individuals, such as patients infected with human immunodeficiency virus (HIV). However, there is limited data regarding long-term B19 viremia in HIV patients. In this study, we investigated virological and hematological findings, and also the clinical outcome, of seven cases of HIV/B19 coinfection (confirmed by PCR) after one year. These cases were provided from a previous study on patients with HIV infection that found B19 DNA in 13 cases. Seven of these 13 patients were available after 1 year, and we retested them for B19 viremia and B19-specific antibodies. B19 IgG was tested by ELISA, and B19 DNA was assessed by nested PCR. Anemia was not observed in these cases. All subjects had cleared viremia, but B19 IgG seroconversion occurred in two cases. No significant changes in CD4 and hemoglobin occurred. The results of this study indicate that B19 infection in HIV patients is a subtle infection and that B19 viremia is not a long-term event.

Frequency and genotype of human parvovirus B19 among Iranian patients infected with HIV.

The human parvovirus B19 (B19) usually causes a subclinical infection in immunocompetent individuals. Whereas immunocompromised individuals such as patients infected with HIV are at risk of persistent anemia due to B19 infection. Only few studies have been carried out on distribution and molecular epidemiology of B19 in Iran. We aimed to determine the frequency and genotype of B19 among Iranian patients infected with HIV. We conducted a survey on 99 HIV patients and 64 healthy controls. IgG and IgM antibodies against B19 were detected by ELISA and B19 DNA was assessed by nested PCR. PCR products were subjected to direct sequencing and classified after phylogenetic analysis. The prevalence of B19 immunoglobulin was 11.1% for IgG and 1% for IgM. B19 DNA was detected in 13.1% of cases. The prevalence of B19 IgG, IgM, and DNA in control group was 25%, 1.6%, and 9.4%, respectively. B19 IgG was significantly lower in HIV group than in normal controls. There was no significant difference regarding anemia between cases and controls. All sequenced B19 isolates belonged to genotype 1A with low genetic diversity. Our findings indicated that in the HAART era, the importance of B19 infections in HIV patients may be limited whereas persistent B19 viremia in the circulation of healthy controls raises a potential concern in blood donations.

The Role of 3'UTR of RNA Viruses on mRNA Stability and Translation Enhancement.

The central dogma of molecular biology explains the flow of genetic information from DNA to functional products such as proteins. In most cases, a linear relationship with a high correlation coefficient exists between the concentration of mRNA, the middle man, and the functional product. Untranslated regions (UTRs) of RNA form a considerable base pairing that contributes to the secondary and tertiary structures of mRNA. The interaction between the mRNA secondary structures (cis-elements), RNA-binding proteins (RBP) and miRs (trans-element) are critical determinants of mRNAs' fate and stability. Among different viral families, the positive sense (+) RNA viruses use the simplest possible strategy of replication and expression, as the same molecule functions both as a genome and mRNA. Additionally, nucleotide composition and codon usage of +RNA viruses are the closest to human codon adaptation index (CAI). Since the origin of replication of viral intermediate RNA molecules is at the 3'-end of the genome, the 3'UTR plays a role in viral RNA replication. Moreover, the messenger role of RNA likely places functional demands on the 3'UTR to serve a role typical of cellular mRNA. This article reviews the effect of 3'UTR of RNA viruses with positive sense and genomes on mRNA stability and translation improvement. A range of animal (e.g., Dengue, Sindbis, Corona and Polio) and plant (Barley yellow dwarf, Brome mosaic, Turnip crinkle, Tobacco mosaic, Cowpea mosaic and Alfalfa mosaic) viruses are examined to highlight the role of 3'UTR in viral survival and as a potential target for pharmaceutical applications.

Down-regulation of immune checkpoints by doxorubicin and carboplatin-containing neoadjuvant regimens in a murine breast cancer model.

OBJECTIVES: Immune checkpoint expression on tumor-infiltrating lymphocytes (TILs) has a correlation with the outcome of neoadjuvant chemotherapy (NAC) in breast cancer. However, the reciprocal effect of these regimens on the quality and quantity of immune checkpoints has hitherto not been addressed. We aimed to evaluate the impact of three NAC regimens on TILs and immune checkpoints in a murine triple-negative breast cancer model. MATERIALS AND METHODS: Syngeneic model of locally-advanced breast cancer was established in immunocompetent mice using a 4T1 cell line. Tumor-bearing animals were treated with human-equivalent dosages of doxorubicin, paclitaxel, paclitaxel and carboplatin combination, and placebo. Infiltration of CD3+, CD8+, and FoxP3+ cells into the tumor was assessed by immunohistochemistry. Expression of immune checkpoints, including PD-1, CTLA-4, and TIM-3, was evaluated by real-time PCR. RESULTS: Doxorubicin led to a significant (P<0.01) increase in the percentage of the stromal infiltrating CD3+ and CD8+ lymphocytes. Doxorubicin also suppressed significantly (P<0.05) the relative expression of PD-1 compared with the placebo. PD-1 expression was significantly (P<0.05) lower in the group treated with paclitaxel and carboplatin combination as compared with the placebo. The relative expression of TIM-3 was significantly (P<0.05) suppressed in doxorubicin-treated mice in comparison with other interventions. CONCLUSION: Our findings hypothesize that NAC with doxorubicin may potentiate antitumor immunity not merely by recruitment of TILs, but via down-regulation of PD-1 and TIM-3 checkpoints. Carboplatin-containing NAC may suppress PD-1 as well.

Expression of Diverse Angiogenesis Factor in Different Stages of the 4T1 Tumor as a Mouse Model of Triple-Negative Breast Cancer.

Purpose: Triple-negative breast cancer (TNBC) is specified by high vascularity and repetitious metastasis. Although several studies have indicated that angiogenesis has an important role in invasive breast cancer, a suitable model of TNBC that can show the exact onset of angiogenesis factors still needs to be developed. The purpose of this study is to determine the expression level of angiogenesis factors in different clinical stages of the 4T1 tumor as TNBC mouse model. Methods: Twenty mice were injected by the 4T1 cell line, and four mice selected as healthy controls. Following by tumor induction, the mice were randomly put into four groups, each contains four mice. Once the tumor volume reached to the early stage (<100 mm3), intermediate stage (100-300 mm3), advanced stage (300-500 mm3), and end stage (>500 mm3), they were removed by surgery. Then, the expression levels of Hif1α, VEGFR1, and VEGFR2 genes, as well as tumor markers of VEGF, bFGF and CD31, were evaluated by qPCR and immunohistochemistry (IHC) respectively. The statistical analysis was done by SPSS version 16. Results: TNBC tumors were confirmed and multi-foci metastasis in the lung were seen. The mRNA and protein expression levels of the angiogenesis factors increased in the early stage and as the tumor grew, their expression level enhanced dramatically. Conclusion: The 4T1 syngeneic mouse tumor may serve as an appropriate TNBC model for further investigation of the angiogenesis and therapies. Moreover, angiogenesis factors are induced before the advanced stage, and anti-angiogenesis therapy is necessary to be considered at the first line of treatment in TBNC.

No Evidence of Human Herpesvirus 8 among Iranian Patients Infected with HIV.

BACKGROUND: Kaposi's sarcoma is a vascular malignancy, which frequently occurs among immunocompromised individuals such as transplant recipients and patients with acquired immunodeficiency syndrome. Human herpesvirus 8 (HHV-8) is considered the etiological agent of all forms of Kaposi's sarcoma. Though some seroepidemiological studies conducted on the prevalence of HHV-8 in Iran, there are insufficient data on the prevalence of HHV-8 viremia in HIV infected patients. We therefore, aimed to determine the prevalence of HHV-8 viremia in general population and HIV infected patients without Kaposi's sarcoma in Tehran, Iran. METHODS: We conducted a cross sectional survey on 99 patients with HIV infection referred to Iranian Research Center for HIV/AIDS and 40 healthy controls in Tehran, Iran from January to April 2014. The presence of HHV-8 DNA was detected in buffy coat samples of enrolled subjects using nested PCR assay. RESULTS: A total of 99 HIV infected patients with mean age of 37.9±10 yr and 40 healthy controls with mean age of 39±11.5 yr were enrolled in the study. The mean CD4 count was 410.3± 211.4 cells/mm(3). HHV-8 DNA was not detected in both healthy control and HIV patient groups. CONCLUSION: This survey showed low rate of HHV-8 DNA in healthy controls and HIV patients. Considering our findings HHV-8 infection does not seem to be widespread in our population. Further studies focusing on different regions of Iran appear to be required to have a more accurate estimation.

Feasibility assessment of in vitro chemoresponse assay on stereotactic biopsies of glioblastoma multiforms: a step towards personalized medicine.

OBJECTIVES: P In vitro chemosensitivity and resistance assays (CSRAs) are a promising tool for personalized treatment of glioblastoma multiform (GBM). These assays require a minimum of 1 to 2 g of tumor specimen for testing, but this amount is not always accessible. We aimed to assess the feasibility and validity of utilizing stereotactic biopsies of GBM in CSRAs. MATERIALS AND METHODS: Single cell suspension was prepared from 1 g weight explants of the established xenograft tumor of GBM. Also, primary culture was carried out on 35 mg weight specimens, as a surrogate for stereotactic biopsies. Then, chemoresponse profile of cells obtained by direct cell disaggregation and primary culture was determined using temozolomide and carmustine by clonogenic assay. RESULTS: There was no statistically significant difference in the cytotoxicity of temozolomide and carmustine between cells obtained from both methods. CONCLUSION: This work supports the feasibility of using stereotactic biopsies of GBM in CSRAs.