Konjac glucomannan (KGM) is a water-soluble polysaccharide derived from the Amorphophallus’s tuber and, as herbal medicine has shown, can suppress tumor growth or improve health. However, there has been no investigation into the effects of KGM on breast tumor-bearing mice. Therefore, in two cohort experiments, we assessed the effect of glucomannan at daily doses of 2 and 4 mg for 28 days as a dietary supplement and also glucomannan in combination with tumor lysate vaccine as an adjuvant. Tumor volume was monitored twice weekly. In addition, TNF-α cytokines and granzyme B (Gr–B) release were measured with ELISA kits, and IL-2, IL-4, IL-17, and IFN-γ were used as an index for cytotoxic T lymphocyte activity. Moreover, TGF-β and Foxp3 gene expression were assessed in a real-time PCR test. The results show that glucomannan as a dietary supplement increased the IFN-γ cytokine and Th1 responses to suppress tumor growth. Glucomannan as a dietary supplement at the 4 mg dose increased the IL-4 cytokine response compared to control groups. In addition, cell lysate immunization with 2 or 4 mg of glucomannan suppressed tumor growth. As an adjuvant, glucomannan at both doses showed 41.53% and 52.10% tumor suppression compared with the PBS group. Furthermore, the administration of glucomannan as a dietary supplement or adjuvant reduced regulatory T cell response through decreasing TGF-β and Foxp3 gene expression in the tumor microenvironment. In conclusion, glucomannan as a dietary supplement or adjuvant enhanced the immune responses of tumor-bearing mice and decreased immune response suppression in the tumor milieu, making it a potentially excellent therapeutic agent for lowering breast tumor growth.

Mycobacterium bovis (M. bovis) is a slow-growing bacteria that can intracellularly reduce selenium ions to elemental selenium nanoparticles (SeNPs). We used bacterial lysates along with vitamin C to help the synthesis of SeNPs coated with M. bovis Bacille Calmette-Guérin (BCG) crude hydrophobic materials. However, the large-scale fabrication, separation, extraction, and purification of intercellular SeNPs which are prepared by using M. bovis, have many complexities. So, we developed a simple method for preparation of above BCG-coated nanoparticles and tested its potential immune-modulatory effects. In the current investigation, we cultivated the M. bovis in conventional media and prepared total cell lysates from this bacterium by just applying freeze and thaw and ultra-sonication. The resulting cell lysates were added to the solution containing selenium ions before adding the ascorbic acid as a reducing agent. At the end of the process, the fabricated selenium nanoparticles were separated by centrifugation and characterized by different instrumentation methods. In the next step, to evaluate the immune-modulatory effects of the hepatitis B surface antigen (HBsAg) vaccine alone, and in combination with plain SeNPs or SeNPs-BCG lysate, the serum level of interferon-gamma (IFN-γ) was determined in different groups by enzyme-linked immunosorbent assay (ELISA). This study showed adjuvant effects of prepared nanoparticles (in both 10 μg/300 μL and 100 μg/300 μL doses) in increasing the level of interferon-gamma (IFN-γ) in comparison with vaccine alone. Moreover, in both doses of SeNPs-BCG lysate, the level of interferon-gamma (IFN-γ) was remarkably higher than the same doses of plain SeNPs. As a result, synthesized SeNPs in the presence of whole-cell lysates of M. bovis indicated a greater ability to induce the interferon-gamma (IFN-γ) compared with other groups. Additionally, its easy fabrication procedure can be considered its superiority.

Background: Brain tumors can be serious and life-threatening when they are treated effectively. Many therapeutic approaches, such as chemotherapy, radiotherapy, and surgery have been used to treat brain tumors. In this regard, selenium supplements have been reported effective. Methods: Selenium Nanoparticles (SeNPs) were produced in two forms of synthetic and biogenic to evaluate their cytotoxicity on brain glioblastoma cell lines. A-172 cell line was cultured in DMEM medium. The cytotoxicity of the synthetic and biogenic SeNP was assessed by MTT assay. Results: There was a significant difference between the group treated with biogenic and synthetic SeNP compared with non-treated cells after 24, 48, and 72 h. Both biogenic and synthetic SeNP increased Bax gene and decreased Bcl-2 gene expression. Conclusion: It seems that biogenic SeNP was more lethal than its synthetic form. Therefore, it should be considered that the method of NP construction may be an important parameter for its bioactivity.