REVIEW | doi:10.20944/preprints201810.0450.v1
Subject: Medicine & Pharmacology, Gastroenterology Keywords: hepatocellular carcinoma; natural killer cell
Online: 19 October 2018 (11:09:02 CEST)
Hepatocellular carcinoma (HCC) is currently the third leading cause of malignancy-related mortalities worldwide. Natural killer (NK) cells are involved in the critical role of first line immunological defense against cancer development. Defects in NK cell functions are recognized as important mechanisms for immune evasion of tumor cells. NK cell function appears to be attenuated in HCC, and many previous reports suggested that NK cells play a critical role in controlling HCC, suggesting that boosting the activity of dysfunctional NK cells can enhance tumor cell killing. However, the detailed mechanisms of NK cell dysfunction in tumor microenvironment of HCC remain largely unknown. A better understanding of the mechanisms of NK cell dysfunction in HCC will help in the NK cell-mediated eradication of cancer cells and prolong patient survival. In this review, we describe the various mechanisms underlying NK cell dysfunction in HCC. Further, we summarize current advances in the approaches to enhance endogenous NK cell function and in adoptive NK cell therapies, to cure this difficult-to-treat cancer.
REVIEW | doi:10.20944/preprints202107.0237.v1
Online: 12 July 2021 (09:38:48 CEST)
Microorganisms including actinomycetes, archaea, bacteria, fungi, yeast, and micro algae are the auspicious source of vital bioactive compounds. In this review, the existing state of the art re-garding antimicrobial molecules from microorganisms has been summarized. The potential an-timicrobial compounds from actinomycetes, particularly Streptomyces sp.; archaea; fungi including endophytic and marine-derived fungi, mushroom; yeast, and microalgae were briefly described. Furthermore, this review briefly summarized the activity and mode of action of bacteriocins, a ribosomally synthesized antimicrobial peptides product of Eurotium sp., Streptomyces parvulus, S. thermophiles, Lactococcus lactis, etc. Bacteriocins have inherent properties such as targeting multi-ple-drug resistant pathogens, which allows them to be considered next-generation antibiotics. Similarly, Glarea lozoyensis derived antifungal lipohexpeptides i.e., pneumocandins, inhibits 1,3-β-glucan synthase of the fungal cell wall and acts as a precursor for the synthesis of caspo-fungin, is also elaborated. In conclusion, this review highlights the possibility of using microor-ganisms as an antimicrobial resource for biotechnological, nutraceutical, and pharmaceutical ap-plications. However, more investigations are still required to separate, purify, and characterize these bioactive compounds and transfer these primary drugs into clinically approved antibiotics.
ARTICLE | doi:10.20944/preprints201801.0010.v1
Online: 2 January 2018 (10:10:51 CET)
Although the phenomenon of serial killers has received great attention from media, governments, and public, very little information is known about them and very few theories are presented by researchers specifically their definition and motives for killing. Through cross tabulation analysis of top ninety-eight serial killers, this present study poses six questions that investigate the correlations between, offender's gender, offender's level of education, time span of killing, killing severity, number of victims, killer's type of abuse, motives for killing, and victim's profile. Findings show that males kill more than females and for longer time, less educated serial killers kill more horribly, female serial killers consider their family members easy target, and finally males kill most for enjoyment and sex and females kill for financial gains.
ARTICLE | doi:10.20944/preprints202004.0292.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: Porphyra tenera; immune; clinical trial; natural killer cells; cytokines
Online: 17 April 2020 (02:15:58 CEST)
Objective: The purpose of this study was to determine if Porphyra tenera extract (PTE) has immune-enhancing effects and is safe in healthy adults. Methods: Subjects (3x103 ≤ peripheral blood leukocyte levels < 8x103 cells/μl) who met the inclusion criteria were recruited for this study. Enrolled subjects (n=120) were randomly assigned to either the PTE group (n=60) who were given 2.5 g/day of PTE (as Porphyra tenera extract) in capsule form or the placebo group (n=60) who were given crystal cellulose capsules with the identical appearance, weight, and flavor as the PTE capsules for 8 weeks. Outcomes were assessed by measuring natural killer cell (NK-cell) activity, cytokines, and upper respiratory infection (URI), and safety parameters were assessed at baseline and 8 weeks. Results: Compared to baseline, NK cell activity (%) increased for all effector cell to target cell ratios in the PTE group after 8 weeks, but there were no changes in the placebo group (p<0.1). Subgroup analysis of 101 subjects without an URI revealed that NK-cell activity in the PTE group tended to be increased for all E:T ratios (E:T=12.5:1 p=0.068; E:T=25:1 p=0.036; E:T=50:1 p=0.081) compared to the placebo group. There was a significant difference between these two groups for the E:T=25:1 ratio, which increased from 20.3±12.0% at baseline to 23.2±12.4% after 8 weeks in the PTE group (p=0.036). There was no significant difference in levels of cytokines between these two groups. Conclusions: PTE supplementation appears to enhance immune function by improving NK-cell activity without adverse effects in healthy adults.
REVIEW | doi:10.20944/preprints202105.0335.v2
Subject: Medicine & Pharmacology, Urology Keywords: Urothelial bladder cancer; Natural Killer Cells; Androgens; Immunosuppression; X Chromosome
Online: 15 September 2021 (12:21:27 CEST)
Men are more likely to develop cancer than women. In fact, male predominance is one of the most consistent cancer epidemiology findings. Additionally, men have a poorer prognosis and an increased risk of secondary malignancies compared to women. These differences have been investigated in order to better understand cancer and to better treat both men and women. In this review, we discuss factors that may cause this gender difference, focusing on urothelial bladder cancer (UBC) pathogenesis. We consider physiological factors that may cause higher male cancer rates, including differences in X chromosome gene expression. We discuss how androgens may promote bladder cancer development directly by stimulating bladder urothelium and indirectly by suppressing immunity. We are particularly interested in natural killer (NK) cells because they are important, but often overlooked anti-cancer lymphocytes.
ARTICLE | doi:10.20944/preprints202108.0494.v1
Subject: Life Sciences, Immunology Keywords: Glioblastoma; immunogenic cell death; innate immunity; natural Killer; macrophages; magnetic hyperthermia
Online: 25 August 2021 (13:45:34 CEST)
Cancer immunotherapies are gaining a large popularity and many of them have been approved as standard second-line or in some cases even as first-line treatment for a wide range of cancers. However, immunotherapy has not shown a clinically relevant success in glioblastoma (GBM), principally due to the brain’s “immune-privileged” status and the peculiar tumor microenvironment (TME) of GBM featured by lack of presence of tumor-infiltrating lymphocytes and the establishment of immunosuppressive mechanisms. Emerging evidence has highlighted the key role played by innate immune cells in immunosurveillance and in initiating and driving immune responses against GBM. Immunogenic cell death (ICD) is a promising approach to elicit direct activation of the innate immune system by inducing in target cancer cells the expression of molecular signatures recognized through a repertoire of innate immune cell pattern recognition receptors (PRRs) by effector innate immune cells. Herein, we explored local mild thermal treatment, generated by using ultrasmall (size ~ 17 nm) cubic-shaped iron oxide nanoparticles exposed to an external alternating magnetic field (AMF), to induce ICD in U87 glioblastoma cells. In accordance with what has been previously observed with other types of tumors, we found that mild hyperthermia modulates the immunological profile of U87 glioblastoma cells by inducing stress-associated signals leading to enhanced phagocytosis and killing of U87 cells by macrophages. Finally, we demonstrated that mild magnetic hyperthermia has a modulatory effect on the expression of inhibitory and activating NK cell ligands on target cells. Interestingly, alteration in the expression of NK ligands, caused by mild hyperthermia treatment, in U87 glioblastoma cells, increased their susceptibility to NK cell killing and NK cell functionality. The overall findings demonstrate that mild magnetic hyperthermia stimulates ICD and sensitizes GBM cells to NK-mediated killing by inducing the upregulation of specific stress ligands, providing a novel immunotherapeutic approach for GBM treatment, with potential to synergize with existing NK cell-based therapies thus improving their therapeutic outcomes.
ARTICLE | doi:10.20944/preprints202107.0484.v1
Subject: Medicine & Pharmacology, Allergology Keywords: metformin; Natural Killer cells; Cytotoxic T lymphocytes; intercellular adhesion molecule-1 (ICAM-1); Natural Killer G2-D (NKG2D) ligands (NKG2DL); lymphocyte function-associated antigen 1 (LFA-1)
Online: 21 July 2021 (10:54:14 CEST)
Solid tumor cells have an altered metabolism that can protect them from cytotoxic lymphocytes. The antidiabetic drug metformin modifies tumor cell metabolism and several clinical trials are testing its effectiveness for the treatment of solid cancers. The use of metformin in hematologic cancers has received much less attention, although allogeneic cytotoxic lymphocytes are very effective against these tumors. We show here that metformin induces expression of Natural Killer G2-D (NKG2D) ligands (NKG2DL) and intercellular adhesion molecule-1 (ICAM-1), a ligand of the lymphocyte function-associated antigen 1 (LFA-1). This leads to enhance sensitivity to cytotoxic lymphocytes. Overexpression of antiapoptotic Bcl-2 family members decrease both metformin effects. The sensitization to activated cytotoxic lymphocytes is mainly mediated by the increase on ICAM-1 levels, which favors cytotoxic lymphocytes binding to tumor cells. Finally, metformin decreases the growth of human hematological tumor cells in xenograft models, mainly in presence of monoclonal antibodies that recognize tumor antigens. Our results suggest that metformin could improve cytotoxic lymphocyte-mediated therapy.
ARTICLE | doi:10.20944/preprints202212.0083.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: Irreversible electroporation; Cytokine-induced killer cells; Combination therapy; Pancreatic cancer; Chemokine receptors
Online: 6 December 2022 (01:31:32 CET)
The current study aimed to investigate the antitumor effects and potent mechanism of cytokine-induced killer (CIK) cells combined with irreversible electroporation (IRE) via an in vitro function assay in an in vivo Panc02 cell–bearing mouse model. We established an in vitro culture assay for CIK cells and determined the proportions of different peripheral lymphocytes. The antitumor effect of the combination of IRE and CIK cells in a Panc02 pancreatic-cancer (PC) subcutaneous-xenograft model was investigated; tumor size and mouse survival rates were recorded. We used flow cytometry (FCM) to analyze the proportion of intratumoral lymphocytes, the expression of chemokine receptors, and the proliferative activity of CIK cells. The proportion of cells that were positive for clusters of differentiation 3 and 8 (CD3+CD8+) and the proportion of CD3+CD56+ cells were both significantly increased after 21 days of in vitro culture. Combined IRE/CIK cell treatment significantly inhibited tumor growth and increased the survival rate of Panc02 cell–bearing mice. Furthermore, infiltration of lymphocytes into tumor tissue was significantly increased by this combination therapy compared with the untreated group or monotherapy group. In addition, IRE significantly enhanced the expression of chemokine receptors elicited by, and the proliferative activity of, CIK cells. In conclusion, IRE combined with CIK cells showed superior antitumor efficacy in a PC subcutaneous-xenograft model, which we attributed to the promotion of lymphocytic infiltration, as well as to upregulation of chemokine receptor expression and of regulators of CIK cell proliferation.
ARTICLE | doi:10.20944/preprints202104.0024.v1
Subject: Life Sciences, Biochemistry Keywords: early life stress; maternal deprivation; immune system; natural killer cells; NK cells
Online: 1 April 2021 (14:01:19 CEST)
Early Life Adversity (ELA) is closely associated with the risk for developing diseases later in life, such as autoimmune diseases, type-2 diabetes and cardiovascular diseases. In humans, early parental separation, physical and sexual abuse or low social-economic status during childhood are known to have great impact on brain development, in the hormonal system and immune responses. Maternal deprivation (MD), the closest animal model available to the human situation, is known to similarly induce long lasting behavioural effects, to cause changes in the HPA axis and to have an impact in the immune system. Even though the immune responses to potential pathogens after early stress have been somehow documented, the mechanisms by which they occur are still not fully understood. Here, we have demonstrated that maternal separation, in both humans and rats, significantly affects the sensitivity of the immune system in adulthood. Particularly, NK cells’ profile and response to target cell lines are significantly changed after childhood adversity. These immune cells in rats are not only less cytotoxic towards YAC-1 cells, but also show a clear increase in the expression of maturation markers after 3h of maternal separation. Similarly, individuals who suffered from ELA display significant changes in the cytotoxic profile of NK cells together with decreased degranulation capacity. Altogether, these results lead us to conclude that one of the key mechanisms by which the immune system becomes impaired after ELA might be due to a shift on the senescent state of the cells, specifically NK cells. Elucidation of such a mechanism highlights the importance of ELA prevention and how NK targeted immunotherapy might help attenuating ELA consequences.
ARTICLE | doi:10.20944/preprints202103.0507.v1
Subject: Arts & Humanities, Anthropology & Ethnography Keywords: autonomous weapons; meaningful human control; hors de combat status; killer robots; military ethics
Online: 22 March 2021 (10:17:19 CET)
Autonomous weapons systems (AWS), sometimes referred to as “killer robots”, are receiving evermore attention, both in public discourse as well as by scholars and policymakers. Much of this interest is connected with emerging ethical and legal problems linked to increasing autonomy in weapons systems, but there is a general underappreciation for the ways in which existing law might impact on these new technologies. In this paper, we argue that as AWS become more sophisticated and increasingly more capable than flesh-and-blood soldiers, it will increasingly be the case that such soldiers are “in the power” of those AWS which fight against them. This implies that such soldiers ought to be considered hors de combat, and not targeted. In arguing for this point, we draw out a broader conclusion regarding hors de combat status, namely that it must be viewed contextually, with close reference to the capabilities of combatants on both sides of any discreet engagement. Given this point, and the fact that AWS may come in many shapes and sizes, and can be made for many different missions, we argue that each particular AWS will likely need its own standard for when enemy soldiers are deemed hors de combat. We conclude by examining how these nuanced views of hors de combat status might impact on meaningful human control of AWS.
ARTICLE | doi:10.20944/preprints202012.0560.v1
Subject: Medicine & Pharmacology, Nursing & Health Studies Keywords: hemodialysis; indirect forest therapy; emotion; fatigue; stress; heart rate variability; natural killer cells
Online: 22 December 2020 (12:42:59 CET)
(1) Background: Most hemodialysis patients may experience physiological and psychological stress. Exposure to nature has been previously reported to reduce the measures of psychological and physiological stress, and immune function. This study aimed to investigate psychological and physiological effects of integrated indirect forest therapy on chronic renal failure patients undergoing hemodialysis. (2) Methods: As a quasi-experiment, this study employed a nonequivalent control group, repeated measurements, and a non-synchronized design. A total of 54 participants were included: 26 and 28 in the experimental and control groups, respectively. During hemodialysis, five types of forest therapy stimuli (visual, auditory, olfactory, tactile, and motor) were applied 3 times per week for 4 weeks during 15-minute sessions. (3) Results: Positive but not negative emotion measures differed between the groups after the intervention. Fatigue and physiological stress levels were significantly reduced in the experimental group, whereas no significant difference was found between the groups on the measures of psychological stress. Activation of both the parasympathetic and sympathetic nervous systems was similar in both groups, as was the number of natural killer cells. (4) Conclusion: Integrated indirect forest therapy may help increase positive emotions and reduce fatigue and stress levels during hemodialysis in patients with chronic renal failure.
REVIEW | doi:10.20944/preprints202007.0139.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: Natural killer cells; NK cells; adoptive cell transfer; NK-92; CAR-NK; haNK; t-haNK
Online: 7 July 2020 (17:44:06 CEST)
Cellular therapy has emerged as an attractive option for the treatment of cancer, and adoptive transfer of chimeric antigen receptor (CAR) expressing T cells has gained FDA approval in hematologic malignancy. However, limited efficacy has been observed utilizing CAR-T therapy in solid tumors. Natural killer (NK) cells are crucial for tumor surveillance and exhibit potent killing capacity of aberrant cells in an antigen-independent manner. Adoptive transfer of unmodified allogeneic or autologous NK cells has shown limited clinical benefit due to factors including low cell number, low cytotoxicity and failure to migrate to tumor sites. To address these problems, immortalized and autologous NK cells have been genetically engineered to express high affinity receptors (CD16), CARs directed against surface proteins (PD-L1, CD19, Her2, etc.) and endogenous cytokines (IL-2 and IL-15) that are crucial for NK cell survival and cytotoxicity, with positive outcomes reported by several groups both preclinically and clinically. With a multitude of NK cell-based therapies currently in clinic trials, it is likely they will play a crucial role in next-generation cell therapy-based treatment. In this review we will highlight the recent advances and limitations of allogeneic, autologous and genetically enhanced NK cells used in adoptive cell therapy.
ARTICLE | doi:10.20944/preprints201909.0324.v1
Subject: Materials Science, Nanotechnology Keywords: immunotherapy; human hepatoma cells; programmed cell death protein 1 (pd-1); magnetic nanoparticles; peptide-imprinted polymer; natural killer cells
Online: 29 September 2019 (05:28:46 CEST)
Programmed cell death protein 1 (PD-1) is a biomarker on the surface of cells that has a role in promoting self-tolerance by suppressing the inflammatory activity of T cells. In this work, one peptide of PD-1 was used as the template in molecular imprinting. The magnetic peptide-imprinted poly(ethylene-co-vinyl alcohol) composite nanoparticles (MPIP NPs) were characterized by dynamic light scattering (DLS), high-performance liquid chromatography (HPLC), Brunauer-Emmett-Teller (BET) analysis and superconducting quantum interference device (SQUID) analysis. Natural killer-92 (NK-92) cells were added to these composite nanoparticles and then incubated with human hepatoma (HepG2) cells. The viability and apoptosis pathway of HepG2 were then studied using cell counting kit-8 (CCK8) and the quantitative real-time polymerase chain reaction (qRT-PCR), respectively. These nanoparticles were found significantly enhance the activity of natural killer cells toward HepG2 cells by increasing expression of NK-kB, caspase 8 and especially caspase 3.