Biofilm is complex and consists of bacterial colonies that reside in an exopolysaccharide matrix that attaches to foreign surfaces in a living organism. Biofilm frequently leads to nosocomial, chronic infections in clinical settings. Since the bacteria in the biofilm have developed antibiotic resistance, using antibiotics alone to treat infections brought on by biofilm is ineffective. This review provides a succinct summary of the theories behind the composition of, formation of, and drug-resistant infections attributed to biofilm and cutting-edge curative approaches to counteract and treat biofilm. The high frequency of medical device-induced infections due to biofilm warrants the application of innovative technologies to manage the complexities presented by biofilm.
Matrix metallaprotinase-9 (MMP-9) is zinc-containing proteinase whose expression and trafficking are frequently altered in cancer. MMP-9 in the plasma membrane and the secreted forms are thought to contribute to the invasive and metastatic properties of malignant tumors. We have manipulated the expression of MMP-9 in prostate tumor cell line LNCaP and measured their capacity to invade through a basement membrane matrix. Stable expression of human MMP-9 in a poorly metastatic LNCaP prostate cancer cell line produced a 2-3-fold increase in MMP-9 activity and a comparable increase in invasiveness. Transient transfection of LNCaP stable clone expressing MMP-9 with MMP-9 antisense oligonucleotide (ASODN) produced 55-90% less MMP-9 than control cells and were proportionately less invasive. In contrast, manipulating MMP-9 levels had no effect on cell migration across an uncoated membrane. A standard MMP-9 inhibitor at a concentration ranging from 1-10 nM, caused a nearly quantitative inhibition of extracellular MMP-9 activity and had significant effect on basement membrane invasion. Collectively, these results confirm the role of MMP-9 in tissue remodeling associated with prostate tumor invasion.
Cannabidiol (CBD) has been shown to slow cancer cell growth and is toxic to human glioblastoma cell lines. Thus, CBD could be an effective therapeutic for glioblastoma. In the present study, we explored the anticancer effect of cannabidiol loaded magnesium-gallate (CBD/Mg-GA) metal–organic framework (MOF) using the rat glioma brain cancer (C6) cell line. Bioactive and microporous magnesium gallate MOF was employed for simultaneous delivery of two potential anticancer agents (gallic acid and CBD) to the cancer cells. Gallic acid (GA), a polyphenolic compound, is part of the MOF framework, while CBD is loaded within the framework. Slow degradation of CBD/Mg-GA MOF in physiological fluids leads to sustained release of GA and CBD. CBD's anti-cancer actions target mitochondria, inducing their dysfunction and generation of harmful reactive oxygen species (ROS). Anticancer effects of CBD/Mg-GA include a significant increase in ROS production and a reduction in anti-inflammatory responses as reflected by a significant decrease in TNF-α expression levels. Molecular mechanisms that underlie these effects include the modulation of NF-κB expression, triggering the apoptotic cascades of glioma cells. CBD/Mg-GA MOF has potential anti-cancer, anti-inflammatory and anti-oxidant properties. Thus, the present study demonstrates that CBD/Mg-GA MOF may be a promising therapeutic for glioblastoma.
The standard of care chemotherapy drug presently used to treat castration-resistant prostate cancer (CRPC), docetaxel (Doc), also develops chemoresistance, thereby reducing its clinical utility. Since resistance to chemotherapy drugs can be overcome by co-treatment with plant-based bio-active compounds we undertook the present study to evaluate if quercetin (Que), a flavonoid present in plants such as onions, apples, olives, and grapes can enhance the efficacy of Doc. We studied the separate and combined effects of Que and Doc at different doses and different combination approaches in two different prostate cancer cell lines, DU-145 (moderately aggressive) and PC-3 (very aggressive), and assessed the effects of these combinations on viability, proliferation, and apoptosis. Monotherapy with these drugs showed dose-dependent cytotoxicity; however, only Doc monotherapy showed a statistically significant difference in IC50 levels (IC50 = 4.05 ± 0.52 nM for PC-3 and IC50 = 2.26 ± 0.22 nM for DU-145). In combination treatment, we used three different treatment approaches (TAP). The concentrations and range analyzed were chosen based on the approximate cytotoxicity of 30–50% when the drugs were used individually. Our observations indicate that the most beneficial effect of the Que and Doc combination was obtained with the TAP-2 approach, which is pre-treatment with all doses of Que for 24 h followed by low doses of Doc for another 24 h. Using this approach, we observed synergism at low concentrations of Doc (0.5 and 1.0 nM) and all concentrations of Que. An additive effect was observed at moderate and high concentrations of Doc (1.5, 2.0, and 2.5 nM) and all concentrations of Que in both cell lines. The TAP-2 strategy was also helpful in overcoming Doc resistance in resistant CaP cells. In summary, Que improved the therapeutic effect of Doc in CRPC, and it is proposed that this improvement is mediated through multiple mechanisms. This study provides a novel therapeutic modality for an effective combination using Doc and Que to enhance the efficacy of Doc in an innocuous manner for Doc resistance and CRPC treatment.