The quest for the holy grail: overcoming challenges in expanding human hematopoietic stem cells for clinical use

Hematopoietic stem cell (HSC) transplantation has been the golden standard for many hematological disorders. However, the number of HSCs obtained from several sources, including umbilical cord blood (UCB), often is insufficient for transplantation. For decades, maintaining or even expanding HSCs for therapeutic purposes has been a "holy grail" in stem cell biology. Different methods have been proposed to improve the efficiency of cell expansion and enhance homing potential such as co-culture with stromal cells or treatment with specific agents. Recent progress has shown that this is starting to become feasible using serum-free and well-defined media. Some of these protocols to expand HSCs along with genetic modification have been successfully applied in clinical trials and some others are studied in preclinical and clinical studies. However, the main challenges regarding ex vivo expansion of HSCs such as limited growth potential and tendency to differentiate in culture still need improvements. Understanding the biology of blood stem cells, their niche and signaling pathways has provided possibilities to regulate cell fate decisions and manipulate cells to optimize expansion of HSCs in vitro. Here, we review the plethora of HSC expansion protocols that have been proposed and indicate the current state of the art for their clinical application.

Anticancer Effect of Enterococcus faecium, Isolated from Vaginal Fluid, on Ovarian Cancer Cells

Background

Given the association between cervicovaginal microbiota and OVC, we investigated the effect of Enterococcus faecium conditioned medium (CM) on OVC (Caov-4) cells.

Methods

CM was obtained from the bacterium E. faecium isolated from the vagina of healthy women. The Caov-4 cells were treated with varying concentrations of CM that comprised co-cultured bacteria with 0.2, 0.5, 1, 1.5, and 2 OD for 12, 24, and 48 h. The apoptosis and growth of cancer cells were evaluated by 4′,6-diamidino-2-phenylindole (DAPI) staining, flow cytometry, and DNA laddering assay. Moreover, the expression of PTEN, BAX, BCL2, and AKT1 genes were analyzed using real-time PCR.

Results

The CM at a concentration of 0.5 OD from the cultured bacteria and incubation time of 48 h showed the highest negative effect on the viability of cancer cells. The CM treatment increased DNA fragmentation and also induced apoptosis in Caov-4 cells. Interestingly, CM could decrease the expression of proapoptotic genes were less, while antiapoptotic genes were more than fluorouracil in the presence of CM.

Conclusion

CM of human-derived E. faecium could have an anticancer effect on OVC cells in a concentration- and time-dependent manner. This study demonstrated that E. faecium secretes anticancer substances into the CM, which could directly affect the viability and apoptosis of cancer cells.

Anticancer Effect of Enterococcus faecium, Isolated from Vaginal Fluid, on Ovarian Cancer Cells

Background

Given the association between cervicovaginal microbiota and OVC, we investigated the effect of Enterococcus faecium conditioned medium (CM) on OVC (Caov-4) cells.

Methods

CM was obtained from the bacterium E. faecium isolated from the vagina of healthy women. The Caov-4 cells were treated with varying concentrations of CM that comprised co-cultured bacteria with 0.2, 0.5, 1, 1.5, and 2 OD for 12, 24, and 48 h. The apoptosis and growth of cancer cells were evaluated by 4′,6-diamidino-2-phenylindole (DAPI) staining, flow cytometry, and DNA laddering assay. Moreover, the expression of PTEN, BAX, BCL2, and AKT1 genes were analyzed using real-time PCR.

Results

The CM at a concentration of 0.5 OD from the cultured bacteria and incubation time of 48 h showed the highest negative effect on the viability of cancer cells. The CM treatment increased DNA fragmentation and also induced apoptosis in Caov-4 cells. Interestingly, CM could decrease the expression of proapoptotic genes were less, while antiapoptotic genes were more than fluorouracil in the presence of CM.

Conclusion

CM of human-derived E. faecium could have an anticancer effect on OVC cells in a concentration- and time-dependent manner. This study demonstrated that E. faecium secretes anticancer substances into the CM, which could directly affect the viability and apoptosis of cancer cells.

Human cardiac organoids: A recent revolution in disease modeling and regenerative medicine

Three-dimensional (3D) myocardial tissues for studying human heart biology, physiology and pharmacology have recently received lots of attention. Organoids as 3D mini-organs are created from multiple cell types (i.e. induced pluripotent stem cells (iPSCs) or embryonic stem cells (ESCs)) with other supporting co-cultured cells such as endothelial cells or fibroblasts. Cardiac organoid culture technologies are bringing about significant advances in organ research and allows for the establishment of tissue regeneration and disease modeling. The present review provides an overview of the recent advances in human cardiac organoid platforms in disease biology and for cardiovascular regenerative medicine.

Architecting oxidized alginate methacrylate hydrogels with tunable characteristics by altering the sequence of the cross-linking steps, methacrylation reaction time, and polymer concentration

In this study, biodegradable oxidized methacrylated alginate (OMA) hydrogels with controllable mechanical properties were engineered. An ionic and photo cross-linking combination was employed to fabricate dual cross-linked hydrogels. By altering the degree of methacrylation and polymer concentration, hydrogels with an elastic modulus of 4.85 ± 0.13 to 21.02 ± 0.91 kPa, controllable swelling, and degradation kinetics, and cross-link density in the range of 1.0 × 10^-5 to 6.5 × 10^-5 mol/cm³ were obtained. Moreover, evaluating the effect of cross-linking sequence on the hydrogels' mechanical properties demonstrated that in comparison to the hydrogels fabricated by ionic cross-linking followed by photo-polymerization, hydrogels produced by photo-polymerization followed by ionic cross-linking retain a stiffer gel network with more compact structure. Cytocompatibility examination was performed via MTT assay against L929 fibroblasts, and all the hydrogel samples demonstrated high cell viability (>80%). The findings demonstrate the significant effect of the sequence of cross-linking as a novel tool to tune the OMA hydrogel's final properties which can serve as a useful platform for tissue engineering applications.

A comprehensive systematic review of the effectiveness of Akkermansia muciniphila, a member of the gut microbiome, for the management of obesity and associated metabolic disorders

AIMS AND BACKGROUND

Obesity is recognised as a significant public health burden worldwide. Recently the cross-talk between gut microbiota and obesity has attracted much attention. To that end, Akkermansia muciniphila has been proposed as a promising microbe to manage obesity. In the present systematic review, we evaluated evidence on the effectiveness and mechanisms of action of Akkermansia muciniphila supplementation in the management of obesity.

METHODS

Electronic databases of MEDLINE, PubMed, Scopus, Web of Science, and Google Scholar were searched thought March 2020 to identify relevant published articles, and eligible articles were systematically reviewed.

RESULTS AND CONCLUSIONS

Fifteen studies were included in the present study. Findings from the present review, which included human and animal (rodent) models support the effectiveness of Akkermansia supplementation as a novel therapeutic approach for the management of obesity and metabolic complications associated with obesity. However, future clinical trials are warranted to verify these outcomes.

An evaluation on potential anti-oxidant and anti-inflammatory effects of Crocin

Crocin, an active ingredient derived from saffron, is one of the herbal components that has recently been considered by researchers. Crocin has been shown to have many anti-inflammatory and antioxidant properties, and therefore can be used to treat various diseases. It has been shown that Crocin has a positive effect on the prevention and treatment of cardiovascular disease, cancer, diabetes, and kidney disease. In addition, the role of this substance in COVID-19 pandemic has been identified. In this review article, we tried to have a comprehensive review of the antioxidant and anti-inflammatory effects of Crocin in different diseases and different tissues. In conclusion, Crocin may be helpful in pathological conditions that are associated with inflammation and oxidative stress.

Sodium selenite and Se-enriched yeast supplementation in atherosclerotic patients: Effects on the expression of pyroptosis-related genes and oxidative stress status

BACKGROUND AND AIMS

Atherosclerosis as a chronic inflammatory disorder of the arterial wall is the main leading cause of the cardiovascular disease (CVD). Caspase-dependent pyroptosis plays a pivotal role in the pathogenesis of CVD. Selenium (Se) is an important component of the antioxidant defense and plays a crucial role in cardiovascular health. This study aimed to investigate the effects of daily consumption of sodium selenite and Se-enriched yeast on the expression of pyroptosis-related genes, and biomarkers of oxidative stress in patients with atherosclerosis.

METHODS AND RESULTS

In this randomized, double-blinded, placebo-controlled clinical trial, 60 patients with atherosclerosis were recruited. Participants received 200 μg/day of sodium selenite, Se-enriched yeast, or placebo for 8 following weeks. The pyroptosis-related genes' mRNA expression in peripheral blood mononuclear cells (PBMCs) was assessed before and after the intervention. Also, the levels of superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO), and glutathione peroxidases (GPX) were measured at baseline and following the intervention. Following sodium selenite and Se-enriched yeast supplementation, the relative expression levels of TLR4, ASC, NLRP3, and NF-κB1 were significantly downregulated (p < 0.05). Furthermore, the changes in GPX were significantly increased after selenite and yeast supplementation (p < 0.05). Also, selenite and yeast consumption caused a statistically significant decrease in the change of MDA level (p < 0.05).

CONCLUSION

In summary, these findings showed that Se supplementation may reduce inflammation through down-regulation of some pro-inflammatory genes, improving antioxidant defenses in atherosclerosis patients. Further research is required to come to a definite conclusion of selenium supplementation on the CVD risk. This study was registered on the Iranian Registry of Clinical Trials website (identifier: RCT20110123005670N28; https://www.irct.ir/).

Melatonin as a Therapeutic Agent for the Inhibition of Hypoxia-Induced Tumor Progression: A Description of Possible Mechanisms Involved

Hypoxia has an important role in tumor progression via the up-regulation of growth factors and cellular adaptation genes. These changes promote cell survival, proliferation, invasion, metastasis, angiogenesis, and energy metabolism in favor of cancer development. Hypoxia also plays a central role in determining the resistance of tumors to chemotherapy. Hypoxia of the tumor microenvironment provides an opportunity to develop new therapeutic strategies that may selectively induce apoptosis of the hypoxic cancer cells. Melatonin is well known for its role in the regulation of circadian rhythms and seasonal reproduction. Numerous studies have also documented the anti-cancer properties of melatonin, including anti-proliferation, anti-angiogenesis, and apoptosis promotion. In this paper, we hypothesized that melatonin exerts anti-cancer effects by inhibiting hypoxia-induced pathways. Considering this action, co-administration of melatonin in combination with other therapeutic medications might increase the effectiveness of anti-cancer drugs. In this review, we discussed the possible signaling pathways by which melatonin inhibits hypoxia-induced cancer cell survival, invasion, migration, and metabolism, as well as tumor angiogenesis.

Will stem cells from fat and growth factors from blood bring new hope to female patients with reproductive disorders?

Female reproductive system disorders (FRSD) with or without infertility are prevalent women's health problems with a variety of treatment approaches including surgery and hormone therapy. It currently considering to sub-branch of regenerative medicine including stem cells or growth factors injection-based delivery treatment might be improved female reproductive health life. The most common products used for these patients treatment are autologous cell or platelet-based products from patients, including platelet-rich plasma, plasma rich in growth factor, platelet-rich fibrin, and stromal vascular fraction. In this review, we discuss each of the above products used in treatment of FRSD and critically evaluate the clinical outcome.

Current approaches in identification and isolation of cancer stem cells

Cancer stem cells (CSCs) are tumor cells with initiating ability, self-renewal potential, and intrinsic resistance to conventional therapeutics. Efficient isolation and characterization of CSCs pave the way for more comprehensive knowledge about tumorigenesis, heterogeneity, and chemoresistance. Also a better understanding of CSCs will lead to novel era of both basic and clinical cancer research, reclassification of human tumors, and development of innovative therapeutic strategies. Finding novel diagnostic and effective therapeutic strategies also enhance the success of treatment in cancer patients. There are various methods based on the characteristics of the CSCs to detect and isolate these cells, some of which have recently developed. This review summarized current techniques for effective isolation and characterization of CSCs with a focus on advantages and limitations of each method with clinical applications.

Lactobacillus plantarum induces apoptosis in oral cancer KB cells through upregulation of PTEN and downregulation of MAPK signalling pathways

Introduction: The oral tumor is the sixth most prevalent type of cancer worldwide and the second leading cause of cancer-related mortality. Although chemotherapy and immunotherapy are the main strategies for the treatment of oral cancer, an emergence of inevitable resistance to these treatment modalities is the major drawback that causes recurrence of the disease. Nowadays, probiotics have been suggested as adjunctive and complementary treatment modalities for improving the impacts of chemotherapy and immunotherapy agents. Probiotics, the friendly microflora in our bodies, contribute to the production of useful metabolites with positive effects on the immune system against various diseases such as cancer. Methods:Lactobacillus plantarum is one of the most important bacteria, which commensally live in the human oral system. In the current study, the impacts of L. plantarum on maintaining oral system health were investigated, and the molecular mechanisms of inhibition of oral cancer KB cells mediated by L. plantarum were evaluated using real-time polymerase chain reaction (PCR) and FACS flow cytometry analyses. Results: Our findings showed that L. plantarum is effective in the signal transduction of the oral cancer cells through upregulation and downregulation of PTEN and MAPK pathways, respectively. Conclusion: Based on the biological effects of oral candidate probiotics candidate bacterium L. plantarum on functional expression of PTEN and MAPK pathways, this microorganism seems to play a key role in controlling undesired cancer development in the oral system. Taken all, L. plantarum is proposed as a potential candidate for probiotics cancer therapy.

Communal institutions for the management of rangeland resources and dairy production in Taleghan Valley, Northern Iran

Mutual help among pastoralists plays a key role in herding in rural Iran where pastoralists share a rich knowledge of dairy production. Nariyan village, located in the Taleghan region in Northern Iran, was chosen for this study on local traditions of the dairy production chain because it is still largely based on reciprocal sharing of labour and milk and local traditions of social cohesion. The results reveal that an elaborate network of communal institutions, based on seasonal cooperation, exists among pastoralists that regulate the use and management of milk and milk products. Different social roles, such as those of owners of herds of different sizes, herd manager and shepherds, are organised in a traditional co-operative institution, called Shirvâreh, a summer seasonal cooperative that strengthens social ties among the pastoralists and guarantees an efficient dairy production chain for subsistence and marketing. Precise data on milk-sharing reciprocity, such as are provided in this paper, seem to be rare for this geographical region if there are any at all, and this fills a gap in empirical rangeland science as it adds to the theory of traditional knowledge being a means to harmonise societal inequalities.

Front-line paclitaxel–vinorelbine versus paclitaxel–carboplatin in patients with advanced non-small-cell lung cancer: a randomized phase III trial

PURPOSE

This randomized phase III trial of advanced or metastatic non-small-cell lung cancer (NSCLC) was designed to compare a standard treatment such as carboplatin (CRP)-paclitaxel (PCT) with a new combination, vinorelbine (VRL)-PCT-two agents acting in microtubules.

PATIENTS AND METHODS

Three hundred and sixty patients (stage IIIa, IIIb and IV) were included and evaluated for response rate, survival and toxicity. Arm A patients were treated with the control combination of CRP 6 AUC and PCT 175 mg/m(2) repeated every 3 weeks for six cycles, and arm B with the investigational combination of VRL 25 mg/m(2) and PCT 135 mg/m(2) repeated every 2 weeks for nine cycles. The patients were well balanced with respect to gender, disease stage and performance status. Arm A received 849 cycles (mean 4.59 per patient) and arm B 951 cycles (mean 5.39 per patient).

RESULTS

Complete and partial response rates were 45.95% and 42.86% for arms A and B, respectively. Median survival was 11 and 10 months, 1-year survival 42.7% and 37.85% and 2-year survival 10.12% and 19% for arms A and B, respectively. Toxicity was similar in all patients, except for neutropenia, which was significantly greater in arm B.

CONCLUSIONS

PCT combined with VRL produces similar (non-significant) response rates, survival and toxicity (except for neutropenia, as noted above) to standard CRP-PCT treatment in untreated advanced-stage NSCLC.