The effect of mitochondria inhibition on natural killer cells cytotoxicity in triple-negative breast cancer cells

Triple-Negative Breast Cancer (TNBC), the most common invasive breast cancer, depicts cancer poor response to conventional therapies. The clinical management of TNBC is a challenging issue. Natural killer (NK) cell therapy in the field of cancer treatment is rapidly growing however, regarding the immunogenicity of breast cancer cells, this type of therapy has shown limited efficacy. Recently, targeting tumor biomarkers has revolutionized the field of cancer therapy. Mitochondria affects apoptosis and innate immunity. Therefore, in this study, mitochondria were inhibited with Tigecycline in stimulating the cytotoxicity of NK cells against TNBC cell lines. MDA-MB-468 and MDA-MB-231 were cultured and treated with IC50 (the half-maximal inhibitory concentration) level of Tigecycline for 48 h and afterward co-cultured with peripheral blood NK cells for 5 h. Lastly, the inhibitory effects of mitochondria on the cytotoxicity of NK cells and apoptosis of TNBC cells were evaluated. Moreover, the expression of apoptotic-related genes was studied. The results showed that mitochondria inhibition increased NK cells cytotoxicity against TNBC cells. Moreover, NK cell/mitochondria inhibition in a combinative form improved apoptosis in TNBC cells by the upregulation of Bad and Bid expression. In conclusion, Tigecycline inhibited mitochondria and sensitized TNBC cells to NK cell therapy. Therefore, mitochondria inhibition could help NK cells function properly.

The dysfunction of natural killer cells is essential for the development of type 1 diabetes

Type 1 diabetes (T1D) is characterized by destruction of pancreatic insulin-producing beta cells by immune cells. In general, environmental and genetic factors can lead to immunological self-tolerance in TID. It is clear that the innate immune system, especially natural killer (NK) cells, is involved in the pathogenesis of T1D. Aberrant NK cell frequencies associated with dysregulation of inhibitory and activating receptors contribute to the initiation and progression of T1D. As T1D is incurable and the metabolic disturbances caused by T1D severely impact patients, a better understanding of NK cell behavior in T1D may facilitate disease treatment strategies. The current review focuses on the role of NK cell receptors in T1D and also highlights ongoing efforts to manipulate key checkpoints in NK cell-targeted therapies.

Cord blood stem cell-generated KIR+NK cells effectively target leukemia cell lines

Acute lymphoid (ALL) and myeloid leukemia (AML) are known to be invasive and highly lethal hematological malignancies. Because current treatments are insufficient and have a variety of side effects, researchers are looking for new and more effective therapeutic methods. Interestingly, ongoing efforts to find the best approach to optimize NK cell anti-leukemia potential shed light on the successful treatment of cancer. Mature KIR⁺NK cells ability to remove HLA Class-I deficient cells has been exploited in cancer immunotherapy. Here, we generated KIR⁺NK cells from cord blood stem cells using IL-2 and IL-15 cytokines. Our finding underlined the importance of KIR expression in the cytotoxic function of NK cells. Taken together, this study presented an effective in vitro method for the expansion and differentiation of KIR⁺NK cells using cytokines without any feeder cells. Furthermore, the presented culture condition could be useful for the generation of mature and pure NK cells from limited numbers of CD34⁺ cord blood cells and might be used as a novel method to improve the current state of cancer therapy.

A combination of telomerase inhibition and NK cell therapy increased breast cancer cell line apoptosis

Triple-negative breast cancer (TNBC) is a subtype of breast tumor with the highest breast cancer stem cells (BCSCs) content and resistance to conventional treatment. Due to the immunosuppressive tumor microenvironment and immunogenicity of breast cancer cells, the use of immune cells, especially natural killer cells (NK) in the treatment of solid tumors, including breast cancer, has been unsatisfactory. Therefore, identifying novel therapies is requisite for breast cancer treatment. Furthermore, the combination of cancer therapies is an effective strategy to improve therapeutic effectiveness. In this study, we inhibited telomerase (hTERT) with BIBR1532, in stimulating NK cell cytotoxicity against breast cancer cells. The MDA-MB-231 cell line was cured with IC50 level of BIBR1532 for 24 h. Afterward, cells were washed with PBS and were co-cultured with peripheral blood NK cell for 5h. Finally, we assessed the impact of telomerase inhibition on the cytotoxicity of NK cells and apoptosis of breast cancer. Also, the expression of hTERT and apoptotic-related genes were evaluated. The data revealed that inhibition of telomerase increases NK cell cytotoxicity against breast cancer. Furthermore, telomerase inhibition and NK cell synergistically enhanced cell death in breast cancer cells by suppressing hTERT, upregulation of bax, and bad expression. In conclusion, telomerase suppression makes breast cancer cells more sensitive to NK cell therapy. Consequently, the combination of telomerase inhibition and NK cells can be useful in the treatment of breast cancer cells.

Diagnostic of Cytokeratin-19 Gene Expression in Iranian Breast Cancer Patients

Sentinel lymph node (SLN) biopsy is currently the recommended procedure for axillary staging in clinically node-negative early breast cancer at diagnosis. The present study aimed to identify Cytokeratin-19 (CK19) gene profiles that accurately predicted the outcome of breast cancer patients. Fifty tumor samples from breast cancer patients were analyzed for the expression of the CK19 gene using quantitative PCR. Also, normal breast tissues (N = 50) were taken from the same patients that had undergone partial or total mastectomy. This gene signature was confirmed based on tumor's stage, grade, and estrogen receptor (ER) status, using conditional logistic regression. Based on these findings, the negative reported lymph nodes for metastasis had micrometastasis in significant values. There was a significant difference between normal and cancer samples in  CK19 expression. In this sentinel node evaluation, the relationship of this gene with tumor characteristics needs to be established and discussed finding a clear role for this gene in tumor outcome.

An in silico comparative transcriptome analysis identifying hub lncRNAs and mRNAs in brain metastatic small cell lung cancer (SCLC)

Small cell lung cancer (SCLC) is a particularly lethal subtype of lung cancer. Metastatic lung tumours lead to most deaths from lung cancer. Predicting and preventing tumour metastasis is crucially essential for patient survivability. Hence, in the current study, we focused on a comprehensive analysis of lung cancer patients' differentially expressed genes (DEGs) on brain metastasis cell lines. DEGs are analysed through KEGG and GO databases for the most critical biological processes and pathways for enriched DEGs. Additionally, we performed protein-protein interaction (PPI), GeneMANIA, and Kaplan-Meier survival analyses on our DEGs. This article focused on mRNA and lncRNA DEGs for LC patients with brain metastasis and underlying molecular mechanisms. The expression data was gathered from the Gene Expression Omnibus database (GSE161968). We demonstrate that 30 distinct genes are up-expressed in brain metastatic SCLC patients, and 31 genes are down-expressed. All our analyses show that these genes are involved in metastatic SCLC. PPI analysis revealed two hub genes (CAT and APP). The results of this article present three lncRNAs, Including XLOC_l2_000941, LOC100507481, and XLOC_l2_007062, also notable mRNAs, have a close relation with brain metastasis in lung cancer and may have a role in the epithelial-mesenchymal transition (EMT) in tumour cells.

NK cell dysfunction is linked with disease severity in SARS-CoV-2 patients

SARS‐CoV‐2 first raised from Wuhan City, Hubei Province in November 2019. The respiratory disorder, cough, weakness, fever are the main clinical symptoms of coronavirus disease 2019 (COVID‐19) patients. Natural Killer (NK) cells as a first defense barrier of innate immune system have an essential role in early defense against pulmonary virus. They kill the infected cells by inducing apoptosis or the degranulation of perforin and granzymes. Collectively, NK cells function are coordinated by the transmitted signals from activating and inhibitory receptors. It is clear that the cytotoxic function of NK cells is disrupted in COVID‐19 patients due to the dysregulation of activating and inhibitory receptors. Therefore, better understanding of the activating and inhibitory receptors mechanism could facilitate the treatment strategy in clinic. To improve the efficacy of immunotherapy in COVID‐19 patients, the functional detail of NK cell and manipulation of their key checkpoints are gathered in current review.

Natural Killer (NK) cells as a major innate immunity compartment have a substantial role in the control of infection in coronavirus disease 2019 (COVID‐19) patients. Despite the important role of NK cells in viral diseases, the function of these cells is disrupted in COVID‐19 patients. Dysregulation of the activating and inhibitory receptors and cytokine storm in respiratory air‐way followed by accumulation of disarming NK cells, are major factors in disease severity in COVID‐19 patients. Therefore, it seems that the manipulating of immune checkpoints, the control of excessive secretion of cytokines (anticytokine therapy) and inhibitory receptors targeting by the monoclonal antibodies would be helpful to restore NK cell function

Bone marrow CD34 positive cells may be suitable for collection after death

Hematopoietic stem cells (HSCs) which are characterized with CD34+ phenotype, have a pivotal role in blood cell regeneration. They are located in lowest hypoxic areas in the bone marrow niches. This microenvironment protects them from DNA damage and excessive proliferation, whereas the oxygenated area driving cells out of quiescent state into proliferation. Given the resistance of HSCs to hypoxia, it is reasonable to imagine that they can survive for some time in the absence of oxygen. Here, we evaluated CD34, Bax, Bcl-2, Bcl-xl, and p53 genes expression after death. Moreover, we established the ex-vivo development of HSCs using SCF, FLT3, IL-2, and IL-15 cytokines in culture system. Our finding indicated that although the most of the dead person's mononuclear cells were alive and adequately expressed the CD34 on their surfaces at the first day of isolation, the viability and CD34+/Ki-67 expression declined significantly after culture process. Taken together, our finding indicated that the viability and CD34+ expression was acceptable on day 0 and could be used as a novel method for therapeutic purposes.

Effect of aberrant DNA methylation on cancer stem cell properties

DNA methylation, as an epigenetic mechanism, occurs by adding a methyl group of cytosines in position 5 by DNA methyltransferases and has essential roles in cellular function, especially in the transcriptional regulation of embryonic and adult stem cells. Hypomethylation and hypermethylation cause either the expression or inhibition of genes, and there is a tight balance between regulating the activation or repression of genes in normal cellular activity. Abnormal methylation is well-known hallmark of cancer development and progression and can switch normal stem cells into cancer stem cells. Cancer Stem Cells (CSCs) are minor populations of tumor cells that exhibit unique properties such as self-regeneration, resistance to chemotherapy, and high ability of metastasis. The purpose of this paper is to show how aberrant DNA methylation accumulation affects self-renewal, differentiation, multidrug-resistant, and metastasis processes in cancer stem cells.

Telomerase inhibition on acute myeloid leukemia stem cell induced apoptosis with both intrinsic and extrinsic pathways

AIMS

Acute Myeloid Leukemia (AML) is an invasive and lethal blood cancer caused by a rare population of Leukemia Stem Cells (LSCs). Telomerase activation is a limitless self-renewal process in LSCs. Apart from telomerase role in telomere lengthening, telomerase (especially hTERT subunit) inhibits intrinsic-, extrinsic-, and p53- mediated apoptosis pathways. In this study, the effect of Telomerase Inhibition (TI) on intrinsic-, extrinsic-, p53-mediated apoptosis, and DNMT3a and TET epigenetic markers in stem (CD34⁺) and differentiated (CD34^-) AML cells is evaluated.

MAIN METHODS

High-purity CD34⁺ (primary AML and KG-1a) cells were enriched using the Magnetic-Activated Cell Sorting (MACS) system. CD34⁺ and CD34^- (primary AML and KG-1a) cells were treated with BIBR1532 and then, MTT assay, Annexin V/7AAD, Ki-67 assay, Telomere Length (TL) measurement, and transcriptional alterations of p53, hTERT, TET2, DNMT3a were analyzed. Finally, apoptosis-related genes and proteins were studied.

KEY FINDINGS

TI with the IC50 values of 83.5, 33.2, 54.3, and 24.6 μM in CD34⁺ and CD34^- (primary AML and KG-1a) cells significantly inhibited cell proliferation and induced apoptosis. However, TI had no significant effect on TL. The results also suggested TI induced intrinsic-, extrinsic-, and p53-mediated apoptosis. It was shown that the expression levels of DNMT3a and TET2 epigenetic markers were highly increased following TI.

SIGNIFICANCE

In total, it was revealed that TI induced apoptosis through intrinsic, extrinsic, and p53 pathways and increased the expression of DNMT3a and TET2 epigenetic markers.

Telomerase-based therapies in haematological malignancies

Telomeres are specialized genetic structures present at the end of all eukaryotic linear chromosomes. They progressively get shortened after each cell division due to end replication problems. Telomere shortening (TS) and chromosomal instability cause apoptosis and massive cell death. Following oncogene activation and inactivation of tumour suppressor genes, cells acquire mechanisms such as telomerase expression and alternative lengthening of telomeres to maintain telomere length (TL) and prevent initiation of cellular senescence or apoptosis. Significant TS, telomerase activation and alteration in expression of telomere-associated proteins are frequent features of different haematological malignancies that reflect on the progression, response to therapy and recurrence of these diseases. Telomerase is a ribonucleoprotein enzyme that has a pivotal role in maintaining the TL. However, telomerase activity in most somatic cells is insufficient to prevent TS. In 85-90% of tumour cells, the critically short telomeric length is maintained by telomerase activation. Thus, overexpression of telomerase in most tumour cells is a potential target for cancer therapy. In this review, alteration of telomeres, telomerase and telomere-associated proteins in different haematological malignancies and related telomerase-based therapies are discussed.

Bioinformatics Analysis of Key Genes and Pathways for Medulloblastoma as a Therapeutic Target

Introduction:

One of the major challenges in cancer treatment is the lack of specific and accurate treatment in cancer. Data analysis can help to understand the underlying molecular mechanism that leads to better treatment. Increasing availability and reliability of DNA microarray data leads to increase the use of these data in a variety of cancers. This study aimed at applying and evaluating microarray data analyzing, identification of important pathways and gene network for medulloblastoma patients to improve treatment approaches especially target therapy.

Methods:

In the current study, Microarray gene expression data (GSE50161) were extracted from Geo datasets and then analyzed by the affylmGUI package to predict and investigate upregulated and downregulated genes in medulloblastoma. Then, the important pathways were determined by using software and gene enrichment analyses. Pathways visualization and network analyses were performed by Cytoscape.

Results:

A total number of 249 differentially expressed genes (DEGs) were identified in medulloblastoma compared to normal samples. Cell cycle, p53, and FoxO signaling pathways were indicated in medulloblastoma, and CDK1, CCNB1, CDK2, and WEE1 were identified as some of the important genes in the medulloblastoma.

Conclusion:

Identification of critical and specific pathway in any disease, in our case medulloblastoma, can lead us to better clinical management and accurate treatment and target therapy.

Determinants of survival of common childhood cancers in Iran

Background:

Cancer is the second most common cause of morbidity and mortality in children. This study aimed to epidemiologically and demographically assess common cancers in children in Iran.

Materials and Methods:

This cohort study was conducted on children registered in Mahak Hospital and Rehabilitation Complex (which is a non-governmental organizations (NGO)-related hospital for only malignant diseases). A total of 2232 questionnaires were filled out for cancer patients between 2007 and 2016. The factors including age, gender, race, family history, type of treatment, and type of cancer were entered into Cox regression model to examine their effect on mortality of children diagnosed with cancer.

Results:

The Cox regression model showed that age, race, type of cancer, family history of cancer, and type of treatment had a significant effect on mortality of children diagnosed with cancer (P < 0.05). The hazard ratio (HR) of mortality in 10–15 years old was higher than that of 1–5 years old (P = 0.03, HR = 1.3). The HR of mortality in patients with brain tumor (P < 0.01, HR = 2.24), sarcoma (P < 0.01, HR = 2.32), and neuroblastoma (P < 0.01, HR = 2.56) was twice the value in patients with leukemia. The HR of mortality in patients who had a family history of cancer was higher than that of patients without it (P < 0.01, HR = 1.33). Patients who had undergone chemotherapy along with surgery and radiotherapy (P = 0.02, HR = 0.68) and patients who received chemotherapy along with surgery (P = 0.01, HR = 0.67) had a lower HR of mortality compared to the chemotherapy group.

Conclusion:

Young age, multidisciplinary approach, and absence of family history were associated with lower hazard of death in children diagnosed with cancer; brain tumor, leukemia, and sarcoma had higher hazard of mortality compared to leukemia. Children with a family history of cancer should be under regular follow-up. Treatment should be multidisciplinary and comprehensive.