Iranian Biomedical Journal
Volume:27 Issue: 1, Jan 2023

Immunometabolism is an emerging field in tumor immunotherapy. Understanding the metabolic competition for access to the limited nutrients between tumor cells and immune cells can reveal the complexity of the tumor microenvironment and help develop new therapeutic approaches for cancer. Recent studies have focused on modifying the function of immune cells by manipulating their metabolic pathways. Besides, identifying metabolic events, which affect the function of immune cells leads to new therapeutic opportunities for treatment of inflammatory diseases and immune-related conditions. According to the literature, metabolic pathway such as glycolysis, tricarboxylic acid cycle, and fatty acid metabolism, significantly influence the survival, proliferation, activation, and function of immune cells and thus regulate immune responses. In this paper, we reviewed the role of metabolic processes and major signaling pathways involving in T-cell regulation and T-cell responses against tumor cells. Moreover, we summarized the new therapeutics suggested to enhance anti-tumor activity of T cells through manipulating metabolic pathways.

Differential diagnosis of chronic lymphoproliferative disorders (CLDs) has remained challenging due to the highly variable morphology features and immunophenotyping. Currently, the development of multiple-marker panel analyses by flow cytometry has opened a broad way for diagnosis of CLDs.

We analyzed the peripheral blood and bone marrow samples of 131 patients with B-cell CLDs (including 91 chronic lymphocytic leukemia (CLL), 15 atypical CLL, 14 mantle cell lymphoma (MCL), and 11 CD5-/CD10-lymphoma patients) from April 2018 to April 2019, using a panel of specific markers by flow cytometry.

Our results indicated that the expression pattern of CD22, CD23, FMC-7, and CD5 allowed us to accurately and differentially diagnose the B-CLL, MCL, and CD5-/CD10- lymphoma, while it was not capable of differentiating MCL from atypical CLL. We, however, found that the expression patterns of CD38 and immunoglobulin light chain differed significantly between atypical B-CLL and MCL. CD38 and lambda light chain were remarkably expressed in MCL patients (92.8% and 85%, respectively) compared to the atypical CLL (1.1% and 0% respectively), with the p value less than 0.001 for both markers. In contrast to MCL patients, all the patients with atypical CLL, expressed kappa light chain. The immunohistochemistry method used for cyclin D1 confirmed that the flow cytometry detection of kappa and lambda light chains could provide a new approach with high sensitivity (91%) and moderate specificity (50%) to distinguish MCL patients from atypical B-CLL.

Expression of CD5, CD20 (bright), CD22, FMC-7, CD38, and lambda light chain with no expression of CD23 can accurately detect MCL and differentiate it from atypical B-CLL.

Hypoxic tumor microenvironment is one of the important impediments for conventional cancer therapy. This study aimed to computationally identify hypoxia-related messenger RNA (mRNA) signatures in nine hypoxic-conditioned cancer cell lines and investigate their role during hypoxia.

Nine RNA sequencing (RNA-Seq) expression data sets were retrieved from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified in each cancer cell line. Then 23 common DEGs were selected by comparing the gene lists across the nine cancer cell lines. Reverse transcription-quantitative PCR (qRT-PCR) was performed to validate the identified DEGs. 

By comparing the data sets, GAPDH, LRP1, ALDOA, EFEMP2, PLOD2, CA9, EGLN3, HK, PDK1, KDM3A, UBC, and P4HA1 were identified as hub genes. In addition, miR-335-5p, miR-122-5p, miR-6807-5p, miR-1915-3p, miR-6764-5p, miR-92-3p, miR-23b-3p, miR-615-3p, miR-124-3p, miR-484, and miR-455-3p were determined as common micro RNAs. Four DEGs were selected for mRNA expression validation in cancer cells under normoxic and hypoxic conditions with qRT-PCR. The results also showed that the expression levels determined by qRT-PCR were consistent with RNA-Seq data.

The identified protein-protein interaction network of common DEGs could serve as potential hypoxia biomarkers and might be helpful for improving therapeutic strategies.

The p53 mutation is uncommon in Epstein–Barr virus-linked gastric carcinoma, but its suppression occurs through mechanisms such as ubiquitin specific peptidase 7 (USP7) inhibitions via Epstein–Barr virus nuclear antigen-1 (EBNA1) activity. This study aimed to evaluate the effect of EBNA1 on p53-inhibiting gene expression and the impact of USP7 inhibition on p53 suppression.

MKN-45 cells were transfected with the EBNA1 plasmid. A stable EBNA1 expression cell line was developed through selection based on hygromycin B resistance. Murine double minute (MDM)4, MDM2, sirtuin (SIRT)3, histone deacetylase (HDAC)1, proteasome 26S subunit, Non-ATPase (PSMD)10, USP7, and p53 expression were checked using real-time PCR. Also, cells containing EBNA1 or control plasmid were treated with GNE-6776, and the expression of the interested genes and cell survival were assessed.

MDM4, MDM2, and PSMD10 were significantly upregulated in the MKN-45 cell line following EBNA1 transfection. Morphological changes were observed in the cells harboring EBNA1 after 20 days. In the control cells, USP7 inhibition significantly upregulated the HDAC1, PSMD10, MDM4, and MDM2 genes after 24 h, but downregulated these genes after four days. In the EBNA1-harboring cells, MDM2, MDM4, and PSMD10 genes were significantly upregulated after 24 h, and this effect was sustained for all genes except for MDM4, even after four days. Furthermore, USP7 inhibition induced apoptosis in both cell groups.

EBNA1 enhances the expression of p53-inhibiting genes. Two events—p53 protein overexpression and apoptosis activation—followed the suppression of the USP7 protein and provided evidence for its possible function. The significance of the EBNA1-USP7 interaction in p53 suppression warrants additional investigation and possibly reconsideration.

Phenylketonuria is a common inborn defect of amino acid metabolism in the world. This failure is caused by an autosomal recessive insufficiency of the hepatic enzyme hyperphenylalaninemia (PAH), which catalyzes the irreversible hydroxylation of phenylalanine to tyrosine. More than 1,040 different disease-causing mutations have already been identified in the PAH gene. The most prominent complication of Phenylketonuria, if not diagnosed and treated, is severe mental retardation. Hence, early diagnosis and initiation of nutritional therapy are the most significant measures in preventing this mental disorder. Given these data, we developed a simple and rapid molecular test to detect the most frequent PAH mutations.

Multiplex assay was developed based on the SNaPshot minisequencing approach to simultaneously perform genotyping of the 10 mutations at the PAH gene. We optimized detection of these mutations in one multiplex PCR, followed by 10 single-nucleotide extension reactions. DNA sequencing assay was also used to verify genotyping results obtained by SNaPshot minisequencing.

All 10 genotypes were determined based on the position and the fluorescent color of the peaks in a single electropherogram. Sequencing results of these frequent mutations showed that by using this method, a 100% detection rate could be achieved in the Iranian population.

SNaPshot minisequencing can be useful as a secondary test in neonatal screening for HPA in neonates with a positive screening test, and it is also suitable for carrier screening. The assay can be easily applied for accurate and time- and cost-efficient genotyping of the selected SNPs in various population.

Lysozyme is a part of human and animal noncellular immunity. The regulation of its activity by hormones is poorly studied. The aim of this study was to test the in vitro activity of lysozyme in the presence of catecholamines, natriuretic hormones, and estradiol (E2).

Hormones were incubated with lysozyme, and the activity of lysozome was further determined using a test culture of Micrococcus luteus in the early exponential growth stage. The activity of lysozyme was assessed based on the rate of change in the OD of the test culture. Molecular docking was performed using SwissDock server (http://www.swissdock.ch/docking), and molecular structures were further analyzed and visualized in the UCSF Chimera 1.15rc software.

According to the results, epinephrine and norepinephrine increased lysozyme activity up to 180% compared to the hormone-free enzyme. Changing the pH of the medium from 6.3 to 5.5, increased the lysozyme activity in the presence of E2 up to 150-200 %. The results also showed that exposure to hormones could modify lysozyme activity, and this effect depends on the temperature and pH value. The molecular docking revealed a decrease in the activation energy of the active site of enzyme during the interaction of catecholamines with the amino acid residues, asp52 and glu35 of the active site.

Our findings demonstrate an additional mechanism for the involvement of lysozyme in humoral regulation of nonspecific immunity with respect to human pathogenic microflora and bacterial skin commensals by direct modulation of its activity using human hormones.

The role of inflammatory cytokines, such as tumor necrosis- alpha (TNF-α) and IL-8, in gastric carcinogenesis has been investigated, but their impact remains to be further elucidated.

In this study, we measured the serum concentrations of these cytokines and H. pylori serostatus in dyspeptic patients, presenting with normal mucosa (NM = 53), chronic gastritis (CG = 94), and gastric cancer (GC = 82), by ELISA.

Moderate levels of TNF-α were detected in the NM group (19.9 ± 19.5 pg/ml), which were nearly doubled in patients with CG (35.7 ± 28.0 pg/ml) and drastically declined in GC patients (1.8 ± 5.9 pg/ml). The serum levels of IL-8, however, were not statistically different amongst these three groups.

TNF-α serum concentration seemed to undergo up- and downregulation, when moving from NM to CG and from CG to GC, respectively. If confirmed in a prospective study, this cytokine can behave as a serum indicator of gastric inflammation and malignant transformation.

There is a sheer lack of knowledge in treating rabies in Pakistan. To decrease the number of victims every year, immunization and awareness programs are the basic necessities of Pakistani population. The aim of this study was to highlight the lack of learning strategies and how to overcome this problem, so as to eliminate rabies.

This cross-sectional study was conducted on 692 respondents, aged 8-50 years, in Karachi city of Pakistan from January 2022 to June 2022.  The study was based on demographic characteristics and basic knowledge of rabies, mode of transmission, clinical signs, and range of animal host species. Binary logistic regression analysis was performed to know the risk factor of rabies among different age groups, marital status, occupation, etc.

Results revealed that all the age groups were at risk of the wrong knowledge about rabies, odds = 1.182 and odds = 1.775 for 20-30 and 31-40 years of age, respectively; however, 31-40 years were at the high risk of showing odds=3.597 (95% C.I 1.621-7.983). The correlation of occupation was also checked with rabies knowledge. Only doctors (odds = 1.396) and students (odds = 1.955) showed their unawareness about rabies.

This study highlights the grave situation that holds the country in the form of rabies. Through this study we aspire to raise awareness regarding the transmission, spread, and control of rabies.