Overexpression of lncRNA AFAP1-AS1 as a diagnostic biomarker in non-small cell lung cancer

Background

Long non-coding RNAs (lncRNAs) play important roles in lung tumorigenesis. Among different lncRNAs, overexpression of the lncRNA actin filament‐associated protein 1‐antisense RNA 1 (AFAP1-AS1) in lung tumors has been reported in different studies. In the current study, we aimed to investigate the potential value of lncRNA AFAP1-AS1 as a diagnostic biomarker in lung cancer. Ninety samples from patients with lung cancer were collected from Noor-E-Nejat hospital, Tabriz, Iran. The expression of AFAP1-AS1 was assessed using quantitative reverse transcriptase-PCR (qRT-PCR), followed by the ROC curve analysis to investigate the biomarker potency of AFAP1-AS1.

Results

Our results revealed an upregulation of AFAP1-AS1 in tumor samples as compared to the adjacent non-tumor tissues. We found a significant positive association between AFAP1-AS1 expression and tumor size, as well as tumor stage.

Conclusions

Our results showed overexpression of AFAP1-AS1 and its capacity as a diagnostic biomarker in lung cancer.

Key Epigenetic Events Involved in the Maintenance of Breast Cancer Stem Cells

BACKGROUND

Cancer stem cells (CSCs) are a small subpopulation of cells within tumors and play significant roles in tumorigenesis, metastasis, resistance to treatment, and relapse. They are defined by self-renewal and multi-lineage differentiation, and aggressiveness. Epigenetic modifications, including DNA methylation and acetylation, histone modifications, and non-coding. RNAs (ncRNAs), are partly responsible for CSC potentials and are involved in the modification of key components of crucial pathways such as Notch and Wnt signaling in breast cancer.

OBJECTIVE

In this review, we present an overview of the pathways and epigenetic events that lead to the transformation of mammary gland stem cells to breast CSCs (BCSCs). Based on the data presented here, important pathways such as TGF-β/SMAD2 and Wnt/β-catenin and epigenetic modifications, including histone modifications, DNA methylations, and microRNAs, play important roles in BCSC formation and maintenance.

CONCLUSION

Epigenetic events can alter the expression of genes and functional RNAs, resulting in tumor initiation and progression. Thus, a better understanding of epigenetic modifications involved in BCSC maintenance signaling pathways may help to eliminate or suppress BCSCs and overcome cancer by generating more effective and efficient therapeutic agents.

An updated review of the role of lncRNAs and their contribution in various molecular subtypes of breast cancer

Introduction: Breast cancer (BC) is the most significant threat to women's life. To demonstrate its molecular mechanisms, which results in BC progression, it is crucial to develop approaches to enhance prognosis and survival in BC cases.Areas covered: In the current study, we aimed to highlight the updated data on the oncogenic and tumor suppressive roles of lncRNAs in the progression of various subtypes of BC by specifically putting importance on the functional characteristics, modulatory agents, therapeutic potential, future perspectives and challenges of lncRNAs in BC. We reviewed recent studies published between 2019 and 2020.Expert opinion: The latest investigations have demonstrated that the long non-coding RNAs (lncRNAs) participate in different BC molecular subtypes via different molecular mechanisms; however, the exact functional information of the lncRNAs has yet to be elucidated. The studied lncRNAs could be more applicable as therapeutic targets in BC treatment after pre-clinical and clinical studies.

Interleukin-1 in obesity-related low-grade inflammation: From molecular mechanisms to therapeutic strategies

Since adipose tissue (AT) can upregulate pro-inflammatory interleukins (ILs) via storing extra lipids in obesity, obesity is considered the leading cause of chronic low-grade inflammation. These ILs can pave the way for the infiltration of immune cells into the AT, ultimately resulting in low-grade inflammation and dysregulation of adipocytes. IL-1, which is divided into two subclasses, i.e., IL-1α and IL-1β, is a critical pro-inflammatory factor. In obesity, IL-1α and IL-1β can promote insulin resistance via impairing the function of adipocytes and promoting inflammation. The current study aims to review the detailed molecular mechanisms and the roles of IL-1α and IL-1β and their antagonist, interleukin-1 receptor antagonist(IL-1Ra), in developing obesity-related inflammatory complications, i.e., type II diabetes (T2D), non-alcoholic steatohepatitis (NASH), atherosclerosis, and cognitive disorders. Besides, the current study discusses the recent advances in natural drugs, synthetic agents, and gene therapy approaches to treat obesity-related inflammatory complications via suppressing IL-1.

An Updated Review of the Cross-talk between MicroRNAs and Epigenetic Factors in Cancers

BACKGROUND

Growing evidence indicates that miRs have critical activities in adjusting cellular processes, e.g., cell death, proliferation, and cell-cycle.

INTRODUCTION

This study aimed to provide a concise review of the recent findings regarding tumoral miRs and the cross-talk between miRs and epigenetic factors.

RESULTS

Like the protein-coding genes, the expression levels of miRs are mediated by various transcriptional networks. Indeed, the expression of miRs could be epigenetically modulated by DNA methylation factors and histone modifiers. Furthermore, miRs can suppress critical factors, which mediate epigenetic modifications. Besides, miRs have been implicated in cancer development, metastasis, and chemo-resistance. The aberrant expression of miRs and dysregulated modulatory circuits between miRs and epigenetic factors participate in tumor progression.

CONCLUSION

Identifying tumoral miRs can provide ample opportunity to overcome chemo-resistance and bring a forefront treatment for affected patients.

Microfluidics as efficient technology for the isolation and characterization of stem cells

The recent years have been passed with significant progressions in the utilization of microfluidic technologies for cellular investigations. The aim of microfluidics is to mimic small-scale body environment with features like optical transparency. Microfluidics can screen and monitor different cell types during culture and study cell function in response to stimuli in a fully controlled environment. No matter how the microfluidic environment is similar to in vivo environment, it is not possible to fully investigate stem cells behavior in response to stimuli during cell proliferation and differentiation. Researchers have used stem cells in different fields from fundamental researches to clinical applications. Many cells in the body possess particular functions, but stem cells do not have a specific task and can turn into almost any type of cells. Stem cells are undifferentiated cells with the ability of changing into specific cells that can be essential for the body. Researchers and physicians are interested in stem cells to use them in testing the function of the body's systems and solving their complications. This review discusses the recent advances in utilizing microfluidic techniques for the analysis of stem cells, and mentions the advantages and disadvantages of using microfluidic technology for stem cell research.

MiRNA-138-5p: A strong tumor suppressor targeting PD-L-1 inhibits proliferation and motility of breast cancer cells and induces apoptosis

MicroRNAs are important regulators in multiple cellular processes and are closely related to a variety of cancers including breast cancer (BC). Immunotherapy using different methods such as modulating immune check points has been known as an advanced and successful procedure in cancer treatment. Here we investigated the effects of miRNA-138-5p restoring on Programmed Death Ligand 1 (PD-L-1) expression, BC biological behaviors and T-cell exhaustion. Breast cancer specimens and cell lines were provided and qRT-PCR and western blotting were used to measure the expression of miRNA-138-5p, PD-L-1 and other underlying genes. MTT and colony formation assays and scratch test were employed to specify proliferation, cloning and migration in miRNA-138-5p-transfected MDA-MB-231 cells respectively. DAPI staining assay and flow-cytometry were used to investigate apoptosis rate and cell cycle development. Finally, isolated T-cells were co-cultured with transfected BC cells to explore the effect of miRNA-138-5p on T-cell exhaustion. qRT-PCR revealed down-regulation ofmiRNA-138-5p conversely, up-regulation of PD-L-1 in BC tissues and cell lines. Transfection of miRNA-138-5p into MDA-MB-231 cells inhibited PD-L-1 expression. Western blotting, MTT and colony formation assays affirmed the anti-proliferative effect ofmiRNA-138-5p through down-regulating PI3K/AKT pathway. Also, miRNA-138-5p induced apoptosis in BC cells via up-regulating Caspase-9 and Caspase-3 and arresting cell cycle at sub-G1 phase. Moreover, scratch test and western blotting indicated that miRNA-138-5p inhibits cell motility via targeting MMP2, MMP9 and vimentin but up-regulating E-cadherin. Finally, miRNA-138-5p restrains T-cell exhaustion via suppressing PD-L-1 expression in BC cells leading to disrupt PD-L-1/PD-1 interaction and modulate effector cytokines in T-cells.

Apoptosis Detection Methods in Diagnosis of Cancer and Their Potential Role in Treatment: Advantages and Disadvantages: a Review

INTRODUCTION

Interruption of regulation of apoptosis can play a leading role in cancers where elevated apoptosis causes neurodegeneration, autoimmunity, AIDS, and ischemia. One famous example can be p53's downregulation, which is a tumor suppressor gene, which consequently can cause a decrease in apoptosis rate and intense tumor growth and progression and development and inactivation of 53; it can be extended to many cancers in human. Anyhow, apoptosis is a double-edge sword. There are many trials and studies are going on observation and understanding of different steps involved in apoptosis. Apoptosis has a very major role in carcinogenesis and the treatment of cancer.

AIM

In this updated-cum-comprehensive review, we would like to cover what is apoptosis and cancer and also, will discuss all known methods of apoptosisdetection, their applicability in the treatment of cancer, and their advantages, disadvantages, and limitations.

MATERIAL AND METHODS

Published articles on indexing sources such as PubMed, Scopus from 2000 to date.

RESULT

By considering all above information including each methods pros and cons, these routine methods could be great tool with distinctive qualities in treatmentwhich can be great help from patient perspective and as well from government ad health care system point of view.

CONCLUSION

Accurate diagnosis of cell apoptotic biopathways at different stages assists in evaluating near to exact apoptotic index, which is the perfect sign andindicator for metastasis and also prognosis, thus foreseeing treatment outcome.

Anti-Cancer Effect of Melatonin via Downregulation of Delta-like Ligand 4 in Estrogen-Responsive Breast Cancer Cells

BACKGROUND

The Notch signaling pathway has a key role in angiogenesis and Delta - Like Ligand 4 (DLL4) is one of the main ligands of Notch involved in cell proliferation in sprouting vessels.

OBJECTIVE

In this study, we aimed to evaluate the expression of DLL4 in primary breast tumors and to examine the effect of melatonin on DLL4 expression in vitro.

METHODS

Eighty-five breast tumor and paired adjacent non-tumor tissue samples were collected. Apoptosis assay was performed on breast cancer cells to evaluate melatonin effects. Western blot and quantitative RT-PCR were used to measure DLL4 expression. Then, we investigated the effect of melatonin on the expression of DLL4 in four breast cancer cell lines at RNA and protein levels. We also performed a probabilistic neural network analysis to study genes closely associated with DLL4 expression.

RESULTS

Our results showed a significantly higher expression of DLL4 in tumor tissues compared to non-tumor tissues (P = 0.027). Melatonin treatment substantially attenuated DLL4 expression in BT474 and MCF-7 cells, but not in SK-BR-3 and MDA-MB-231 cells. Also, melatonin induced apoptosis in all four cell lines. Network analysis revealed a set of 15 genes that had close association and interaction with DLL4. DLL4 was overexpressed in breast cancer tissues as compared to the non-tumor tissues.

CONCLUSION

It can be concluded that melatonin treatment attenuated DLL4 expression only in estrogen- responsive breast cancer cells and is able to induce apoptosis in breast cancer cells.

miR-424: A novel potential therapeutic target and prognostic factor in malignancies

microRNAs are endogenous, noncoding RNAs. Showing both tumor-suppressive and oncogenic characteristics, miRNAs can regulate important processes in malignancies. This review aimed at highlighting the recent studies on the contribution of miR-424 to the modulation of carcinogenesis and exploring its probable clinical effectiveness in the diagnosis and therapy of malignancies. The data were extracted from all papers published from 2013 until 2020. Mature miR-424 leads to the degradation of its target transcripts or the suppression of translation via binding to the molecular targets. miR-424 is involved in modulating p53, PI3K/Akt, Wnt, and other molecular pathways, thereby regulating cellular growth, apoptosis, differentiation, chemoresistance, and cancer immunity. miR-424 was introduced as a tumor-suppressive miR in numerous types of cancers while as an oncogene in several cancers. Regarding the cancer dependent role of miR-424, it may be a prognostic and diagnostic biomarker and a potential candidate for the treatment of cancers.

MicroRNA -383-5p restrains the proliferation and migration of breast cancer cells and promotes apoptosis via inhibition of PD-L1

AIMS

MicroRNAs (miRs) play pivotal roles in breast cancer development. The dysregulation of miRs has been associated with PD-L1-mediated immune suppression. This study aimed to examine the effect of transfected miR-383-5p on breast cancer cells and T-cells and its association with clinicopathological features in affected patients.

MAIN METHODS

Initially, miR-383-5p and PD-L1 expression levels were investigated in breast cancer tissues. Then, MDA-MB-231 cells were transfected with miR-383-5p mimics to perform analyses. Cell viability was investigated using the MTT assay, and the annexin V/PI staining assay was performed to examine apoptosis induction. Furthermore, the effect of miR-383-5p on cell migration and cell cycle progression was analyzed using the wound-healing assay and flow cytometry, respectively. Gene and protein expressions were studied using qRT-PCR and western blotting. Finally, the effect of miR-383-5p on T-cells, which were co-cultured with cancer cells, was investigated.

KEY FINDINGS

Compared to non-malignant tissues, PD-L1 was up-regulated, and miR-383-5p expression was downregulated in breast cancer tissues. Moreover, miR-383-5p reduced breast cancer cell viability via inducing apoptosis and modulating the expression of apoptosis-related genes. Besides, miR-383-5p could inhibit the migration of breast cancer cells via down-regulating metastasis-related genes. Besides, transfected miR-383-5p induced the secretion of pro-inflammatory cytokines from T-cells. Furthermore, the results showed that miR-383-5p might exert its tumor-suppressive effect via inhibiting the PI3K/AKT/mTOR pathway. The inhibitory effect of transfected miR-383-5p on the PI3K/AKT/mTOR pathway might be the underlying mechanism for inhibiting tumoral PD-L1 expression.

SIGNIFICANCE

Overall, miR-383-5p can be a promising therapeutic agent for treating breast cancer.

High potential of SOX21 gene promoter methylation as an epigenetic biomarker for early detection of colorectal cancer

Background

Despite the advances in screening during the past decades, colorectal cancer (CRC) still is a leading cause of cancer deaths worldwide. Therefore, the development of new diagnostic methods is necessary.

Aim

The aim of this study was to compare methylation changes of SRY-Box 21 (SOX21) gene promoter in tumor tissues and their normal adjacent mucosa in patients with CRC and to examine the relationship between the methylation levels and demographic/clinicopathological factors.

Materials and methods

A total of 41 CRC patients participated in the present study. After the extraction of DNA and bisulfite treatment of the samples, the methylation levels were determined by using the MethyLight method.

Statistical analysis

Two-sided Mann-Whitney U test was used to compare the median level of methylation in tumor tissues and their adjacent normal mucosa.

Results

The methylation rates in tumor tissue samples were significantly higher compared to their adjacent normal mucosa (P < 0.0001). No association between demographic/clinicopathological factors and methylation status observed in tumor tissues. A receiver operating characteristics curve was constructed and tissue samples exhibited a sensitivity of 80.5% and specificity of 97.6% for SOX21 promoter methylation.

Conclusion

The results of this study indicated the high potential of SOX21 gene promoter methylation as a candidate noninvasive diagnostic biomarker in stool and plasma of colorectal cancer patients. However, further studies with larger sample sizes are required to evaluate the specific role of SOX21 methylation as a biomarker for early detection of CRC.

Advances of microfluidic technology in reproductive biology

According to World Health Organization (WHO) reports about 70 million couples suffer from infertility all over the world. A lot of research groups are working on this issue and have made therapeutic approaches by integrating biology, medicine, genetics, chemistry, psychology, mechanic, and many other branches of science. However, these methods have their own pros and cons. Assisted Reproductive Technologies (ART) has appeared to solve infertility problems. In Vitro Fertilization (IVF), Intracytoplasmic Sperm Injection (ICSI), Intrauterine Insemination (IUI) are the most common and conventional technologies in this regard. There are at least two characteristics of microfluidics, mechanical and biochemical, which can be influential in the field of mammalian gamete and preimplantation embryo biology. These microfluidic characteristics can assist in basic biological studies on sperm, oocyte and preimplantation embryo structure, function and environment. Using microfluidics in sorting sperm, conducting different steps of oocyte selection and preparation, and transferring embryo by passing sub-microliter fluid through microchannels results in low cost and short time. The size and shape of microchannels and the volume of used fluid differs from non-human cells to human cells. The most progressions have been seen in animal models. Results suggest that microfluidic systems will lead to improved efficiencies in assisted reproduction.

Overexpression of HOXA-AS2 LncRNA in Patients with Gastric Cancer and Its Association with Helicobacter pylori Infection

PURPOSE

LncRNAs are regulatory factors that play a prominent role in the carcinogenesis processes and cancer cell ability to invade and metastasize. Hence, lncRNAs are considered as the potential diagnostic and therapeutic biomarkers in diverse malignancies. The present study was designed to assess the difference of HOXA-AS2 gene expression levels in cancerous tissues as compared to marginal noncancerous tissues of gastric cancer patients.

METHODS

Fifty pairs of cancerous and marginal noncancerous tissue of gastric cancer patients were collected in the present study. Then, RNA extraction and cDNA synthesis were performed for all specimens. The qRT-PCR was carried out to examine the difference of HOXA-AS2 gene expression. Furthermore, the association between HOXA-AS2 expression and the clinicopathological features as well as the function of HOXA-AS2 biomarkers was evaluated.

RESULTS

The HOXA-AS2 expression was significantly elevated in cancerous tissues as compared to marginal noncancerous tissues in gastric cancer patients (p < 0.0001). Analysis of gene expression data revealed that there was a significant association between an increased HOXA-AS2 gene expression and clinicopathological features such as tumor size ˃ 5 cm (p = 0.009), lymph node metastasis (p = 0.028), and H. pylori infection (p = 0.011). The results of ROC analysis indicated that HOXA-AS2 with AUC, sensitivity, and specificity of 0.816, 92%, and 70%, respectively, can act as a potential biomarker (CI 95% = 0.7297-0.9023).

CONCLUSION

With regard to the overexpression of HOXA-AS2 in gastric cancer tissues, the mentioned gene may serve as an oncogenic lncRNA in gastric cancer patients. Moreover, HOXA-AS2 can act as a potential biomarker in molecular targeted therapies to recognize and treat gastric cancer patients.

The expression analyses of RMRP, DDX5, and RORC in RRMS patients treated with different drugs versus naïve patients and healthy controls

Although T helper 17 (Th17) lymphocytes protect mucosal barriers against infections, they have been implicated in the development of multiple sclerosis (MS). RORC and DDX5 can regulate Th17 differentiation and the development of MS. Since RMRP, as a long non-coding RNA (lncRNA), can mediate the RORC-DDX5 complex, this lncRNA can be involved in developing MS. This study investigated the expression levels of RORC, DDX5, and RMRP in treatment-naïve relapsing-remitting multiple sclerosis (RRMS) patients, healthy controls, and RRMS patients treated with IFNβ-1α or fingolimod, or dimethyl fumarate (DMF), or glatiramer acetate (GA). There was substantial up-regulation in the expression of RORC, DDX5, and RMRP in treatment-naïve RRMS patients compared to healthy controls. Among the comparisons of their expressions in the different groups of treated patients with treatment-naïve patients, only the down-regulation of the RMRP expression level was significant in IFNβ-1α-treated patients. Also, these changes were more pronounced in female patient groups. Our analyses have highlighted the high diagnostic value of RORC, DDX5, and RMRP in treatment-naïve RRMS patients. Furthermore, RMRP has demonstrated moderate positive correlations with the expression of DDX5 and RORC in treated RRMS patients.

LncRNAs: Potential Novel Prognostic and Diagnostic Biomarkers in Colorectal Cancer

BACKGROUND

Long non-coding RNAs (lncRNAs), a type of regulatory RNAs, play a key role in numerous cellular pathways. Ectopic expression of this group of non-coding RNAs has been specified to be involved in numerous diseases. Moreover, the role of lncRNAs in the initiation and development of cancers including colorectal cancer (CRC) has been acknowledged.

OBJECTIVE

In the present review, the role of lncRNAs as prognostic and diagnostic biomarkers in CRC as well as the molecular mechanisms of their contribution to development of CRC has been addressed.

RESULTS

The presented studies have indicated the ectopic expression of various lncRNAs in CRC. Some lncRNAs which were considered as tumor suppressors were downregulated in the colorectal cancerous tissues compared with healthy controls; however, some with oncogenic effects were upregulated. LncRNAs contribute to tumor development via various molecular mechanisms such as epigenetically controlling the expression of target genes, interacting with miRNAs as their sponge, etc. Conclusion: LncRNAs that have been recognized as prognostic biomarkers may pave the way for clinical management to offer adjuvant treatments for patients with CRC.

Overexpression of long non-coding RNA MCM3AP-AS1 in breast cancer tissues compared to adjacent non-tumour tissues

BACKGROUND

Altered expression of several long non-coding RNAs (lncRNAs) has been described in numerous malignancies, including breast cancer, and some may have a role in carcinogenesis. We hypothesised differences in the expression of lncRNA MCM3AP-AS1 in breast cancer tissues compared to nearby healthy tissues and potential links with clinical features.

METHODS

We tested our hypothesis in 102 pairs of breast cancer tumours and adjacent non-tumour tissues from female patients. After RNA extraction, cDNA synthesis was performed for all specimens. The differential gene expression was assessed using Quantitative Real-Time PCR Technique.

RESULTS

There was a significant overexpression of the lncRNAs in tumour tissues as compared with their adjacent non-tumour tissues (P < 0.001). Expression was significantly linked with the tumour oestrogen receptor expression (P = 0.023) and tumour progesterone receptor expression (P < 0.001). ROC analysis showed an AUC of 0.67 (95% CI 0.60-0.75) (P < 0.001) with sensitivity and specificity of 58% and 76%, respectively.

CONCLUSION

The lncRNA MCM3AP-AS1 may be a novel breast cancer lncRNA with high expression levels in breast cancer patients' tissue. Further investigations are needed to confirm its uses as a potential molecular marker and therapeutic target.

Current perspectives on the dysregulated microRNAs in gastric cancer

Since gastric cancer (GC) is diagnosed at advanced stages, the survival rate is low in affected people. In this regard, investigating the mechanisms underlying GC development, are so critical. MiRNAs, which are small non coding RNAs, as a post transcriptional repressor, regulate expression of target genes by stimulating breakage or transcription suppression of their targets therefore aberrant expression of miRNAs leading to GC carcinogenesis. In the last decades, there have been various studies approving the pivotal role of miRNAs in various phases of GC development including cancer initiation, proliferation, migration, invasion, metastasis, angiogenesis, apoptosis, and drug resistance. Therefore, the present review aimed at summarizing the dysregulated miRNAs which contribute to various cellular and developmental mechanisms such as, proliferation, apoptosis, invasion, migration, and angiogenesis. Moreover, it provides an overview on novel miRNAs involved in drug resistance and circular miRNAs as cancer biomarkers. Thereafter, it is hoped that the present study will shed more light on diagnostic and prognostic biomarkers of GC, and potential GC treatments based on miRNAs.

Antioxidants with two faces toward cancer

Antioxidants are essential in preventing the formation and suppressing the activities of reactive nitrogen and oxygen species. The aim of this study was to review the role of antioxidants in cancer development or prevention. Antioxidants are believed to prevent and treat various types of malignancies. Currently, natural antioxidant compounds have been generally consumed to prevent and treat cancers. Certainly, phenolic compounds extracted from medicinal plants have opened a new prospect with respect to the prevention and treatment of cancers due to having antioxidant characteristics. However, some recently published studies have revealed that antioxidant compounds do not indicate absolute anti-tumor properties. Some antioxidants are helpful in cancer initiation and progression. Taken together, antioxidants demonstrate a two-faced nature toward cancer. However, it is required to conduct further cell culture and in vivo studies to confirm the exact role of antioxidants and then use them for efficient cancer treatments.

Contribution of DNA methylation and EZH2 in SRBC down-regulation in gastric cancer

Gastric cancer (GC), a high mortality malignancy, is induced by genetic and epigenetic factors. DNA and histone methylation play critical roles in tumor suppressor genes inactivation. SRBC (serum deprivation response factor-related gene product that binds to the c-kinase), suggested as a tumor suppressor gene, participates in apoptosis, tumor chemoresistance and DNA damage response and is repressed in various cancers. Inspecting the mechanisms underlying SRBC suppression is important for cancer treatments. We investigated SRBC promoter DNA methylation status and expression of SRBC and EZH2 histone methyltrasferase in gastric cancer. Also, we surveyed SRBC expression after 5-azacitidine and UNC1999 treatments of AGS cell line. In current work, we used gastric adenocarcinoma tissues, marginal samples and normal gastric biopsies. DNA methylation was detected by Methylation- Specific PCR and mRNA expression was measured by Real-Time PCR. SRBC promoter methylation analysis, showed fully and partial methylated versions that were associated with patient's age (p = 0.001). SRBC expression significantly decreased in GC compare with marginal and normal samples (p-value < 0.001). EZH2 showed remarkable up-regulation in GC than controls and demonstrated a strong inverse correlation with SRBC expression (r = - 0.69). Restoration of SRBC expression was observed after 5-azacitidine and UNC1999 applications with a remarkable increase by combinational treatment. We showed that EZH2 plays role in SRBC silencing in addition to DNA methylation. Our study, suggests that DNA methylation and EZH2 are involved in SRBC silencing and their inhibitors can be considered in cancer treatment investigations to overcome chemoresistance induced by SRBC inactivation.

Helicobacter pylori-related risk predictors of gastric cancer: The latest models, challenges, and future prospects

Helicobacter pylori is known as an important determinant of preneoplastic lesions or gastric cancer (GC) risk. The bacterial genotypes may determine the clinical outcomes. However, the evidence for these associations has varied between and within continents, and the actual effect of each gene and corresponding allelic variants are still debatable. In recent years, two new models have been proposed to predict the risk of GC; the phylogeographic origin of H. pylori strains and a disrupted co-evolution between H. pylori and its human host, which potentially explain the geographic differences in the risk of H. pylori-related cancer. However, these models and earlier ones based on putative virulence factors of the bacterium may not fully justify differences in the incidence of GC, reflecting that new theories should be developed and examined. Notably, the new findings also support the role of ancestry-specific germline alteration in contributing to the ethnic/population differences in cancer risk. Moreover the high and low incidence areas of GC have shown differences in transmission ecology, largely affecting the composition of H. pylori populations. As a new hypothesis, it is proposed that any high-risk population may have its own specific risk loci (or variants) as well as new H. pylori strains with national/maybe regional gene pools that should be considered. The latter is seen in the Americas where the rapid evolution of distinct H. pylori subpopulations has been occurred. It is therefore proposed that the deep sequencing of both H. pylori and its human host is simultaneously performed in GC patients and age-sex-matched controls from high-risk areas. The expression and functional activities of the identified new determinants of GC must then be assessed and matched with human and pathogen ancestry, because some of risk loci are ancestry-specific. In addition, potential study-level covariates and moderator variables (eg physical conditions, life styles, gastric microbiome, etc) linked to causal relationships, and their impact, should be recognized and controlled.

Molecular mechanisms of apoptosis induction in K562 and KG1a leukemia cells by a water-soluble copper(II) thiosemicarbazone complex

Thiosemicarbazones (TSCs) and their metal complexes exhibit pronounced and selective cytotoxic potential against a broad span of cancers. Here, we assessed the anti-cancer activity of a water-soluble copper(II) complex of thiosemicarbazone (Cu-TSC) against two cancer cell lines of human leukemia. Our analysis revealed that Cu-TSC treatment results in a time and dose-dependent growth inhibition in K562 and KG1a cells while sparing normal human fibroblast (HFF2) cells. The IC₅₀ values for the Cu-TSC treatment were measured to be 21.7 ± 1.5 µM and 50.25 ± 2.5 µM for K562 and KG1a cells, respectively. Cell cycle analysis indicated that Cu-TSC induces the accumulation of cells in the sub-G1 fraction as well as the reversible arrest in G0/G1 and G2/M phases in K562 and KG1a cells, respectively. Furthermore, the occurrence of apoptosis as the prime mode of cell death was verified through apoptotic body formation, phosphatidylserine externalization, and caspase-3 activation. Additionally, the real-time quantitative PCR analysis revealed that Cu-TSC triggers apoptosis in both cell lines via the upregulation of caspases-8, -9, and the changing of Bax/Bcl2 ratio. Finally, flow cytometric analysis confirmed that Cu-TSC treatment causes the enhancement of reactive oxygen species formation in both K562 and KG1a cells. Altogether, these findings suggest that Cu-TSC is a promising inducer of apoptosis in leukemia cells and carries potential as an anti-cancer compound.