Bulnesia sarmientoi Supercritical Fluid Extract Exhibits Necroptotic Effects and Anti-Metastatic Activity on Lung Cancer Cells

(-)-Guaiol triggers immunogenic cell death and inhibits tumor growth in non-small cell lung cancer

(-)-Guaiol is a sesquiterpenoid found in many traditional Chinese medicines with potent antitumor activity. However, its therapeutic effect and mechanism in non-small cell lung cancer (NSCLC) have not been fully elucidated. In this study, (-)-Guaiol was found to induce immunogenic cell death (ICD) in NSCLC in vitro. Using (-)-Guaiol in vivo, we found that (-)-Guaiol could suppress tumor growth, increase dendritic cell activation, and enhance T-cell infiltration. Vaccination experiments suggest that cellular immunoprophylaxis after (-)-Guaiol intervention can suppress tumor growth. Previous studies have found that (-)-Guaiol induces apoptosis and autophagy in NSCLC. Apoptosis and autophagy are closely related to ICD. To explore whether autophagy and apoptosis are involved in (-)-Guaiol-induced ICD, we used inhibitors of apoptosis and autophagy. The results showed that the release of damage-associated molecular patterns (DAMPs) was partly reversed after inhibition of apoptosis and autophagy. In conclusion, these results suggested that the (-)-Guaiol triggers immunogenic cell death and inhibits tumor growth in NSCLC.

Insight into the Biological Roles and Mechanisms of Phytochemicals in Different Types of Cancer: Targeting Cancer Therapeutics

Cancer is a hard-to-treat disease with a high reoccurrence rate that affects health and lives globally. The condition has a high occurrence rate and is the second leading cause of mortality after cardiovascular disorders. Increased research and more profound knowledge of the mechanisms contributing to the disease’s onset and progression have led to drug discovery and development. Various drugs are on the market against cancer; however, the drugs face challenges of chemoresistance. The other major problem is the side effects of these drugs. Therefore, using complementary and additional medicines from natural sources is the best strategy to overcome these issues. The naturally occurring phytochemicals are a vast source of novel drugs against various ailments. The modes of action by which phytochemicals show their anti-cancer effects can be the induction of apoptosis, the onset of cell cycle arrest, kinase inhibition, and the blocking of carcinogens. This review aims to describe different phytochemicals, their classification, the role of phytochemicals as anti-cancer agents, the mode of action of phytochemicals, and their role in various types of cancer.

Beta-Caryophyllene Enhances the Anti-Tumor Activity of Cisplatin in Lung Cancer Cell Lines through Regulating Cell Cycle and Apoptosis Signaling Molecules

Beta-Caryophyllene (BCP), a natural bicyclic sesquiterpenes, is an abundant biomolecule in red pepper and other plants. Recently, it was reported to reduce the growth and the proliferation as well as enhance the apoptosis in numerous cancer cells, including colorectal, ovarian, bladder cancer and lung cancer. On the other hand, the combination therapy of cisplatin (CDDP) with other phytochemical compounds has synergistically enhanced the killing effect of CDDP on several types of cancer. In the current model, we have tested the role of BCP in enhancing the anti-tumor activity of CDDP on lung cancer cell lines. The results showed that BCP is not toxic at moderate doses and it can prevent lung cancer progression in doses above 75 µM. However, when being combined with CDDP, BCP improved the former chemotherapeutic function through regulating cell cycle, apoptosis and EMT signaling molecules. Gene and protein expression analysis showed that the combined treatment of CDDP and BCP significantly upregulated the level of the cyclin-dependent kinase inhibitor, CDKN1A, and the inhibitor of the apoptosis, BCL-xl2. In addition, the combination treatment reduced the protein level of the apoptosis regulator, BCL-2. Moreover, BCP appears to prohibit the EMT process that is associated with CDDP chemotherapy since the combination treatment induced a significant increase in the level of the epithelial cell marker E-cad that was reduced in CDDP-treated cells. In agreement with that, the combined treatment managed to modulate the effect of CDDP on the mesenchymal transcription factor ZEB-2. Additionally, molecular docking has been conducted to check the virtual interaction of BCP with these and other signaling molecules, but only cyclin-dependent kinase CDK6 was found to virtually bind with BCP, and at four sites with higher and stable biding energy (-7.8). Together, these data indicate that BCP enhances CDDP chemotherapeutic function through regulating the cell cycle, the apoptosis and EMT signaling molecules.

Anti-Cancer Effects of α-Cubebenoate Derived from Schisandra chinensis in CT26 Colon Cancer Cells

α-Cubebenoate derived from Schisandra chinensis has been reported to possess anti-allergic, anti-obesity, and anti-inflammatory effects and to exhibit anti-septic activity, but its anti-cancer effects have not been investigated. To examine the anti-cancer activity of α-cubebenoate, we investigated its effects on the proliferation, apoptosis, and metastasis of CT26 cells. The viabilities of CT26 cells (a murine colorectal carcinoma cell line) and HCT116 cells (a human colon cancer cell line) were remarkably and dose-dependently diminished by α-cubebenoate, whereas the viability of CCD-18Co cells (a normal human fibroblast cell line) were unaffected. Furthermore, α-cubebenoate treatment increased the number of apoptotic CT26 cells as compared with Vehicle-treated cells and increased Bax, Bcl-2, Cas-3, and Cleaved Cas-3 protein levels by activating the MAP kinase signaling pathway. α-Cubebenoate also suppressed CT26 migration by regulating the PI3K/AKT signaling pathway. Furthermore, similar reductions were observed in the expression levels of some migration-related proteins including VEGFA, MMP2, and MMP9. Furthermore, reduced VEGFA expression was found to be accompanied by the phosphorylations of FAK and MLC in the downstream signaling pathway of adhesion protein. The results of the present study provide novel evidence that α-cubebenoate can stimulate apoptosis and inhibit metastasis by regulating the MAPK, PI3K/AKT, and FAK/MLC signaling pathways.

Effects of Gallotannin-Enriched Extract of Galla Rhois on the Activation of Apoptosis, Cell Cycle Arrest, and Inhibition of Migration Ability in LLC1 Cells and LLC1 Tumors

Gallotannin (GT) and GT-enriched extracts derived from various sources are reported to have anti-tumor activity in esophageal, colon and prostate tumors, although their anti-tumor effects have not been determined in lung carcinomas. To investigate the anti-tumor activity of GT-enriched extract of galla rhois (GEGR) against lung carcinomas, alterations in the cytotoxicity, apoptosis activation, cell cycle progression, migration ability, tumor growth, histopathological structure, and the regulation of signaling pathways were analyzed in Lewis lung carcinoma (LLC1) cells and LLC1 tumor bearing C57BL/6NKorl mice, after exposure to GEGR. A high concentration of GT (69%) and DPPH scavenging activity (IC₅₀=7.922 µg/ml) was obtained in GEGR. GEGR treatment exerted strong cytotoxicity, cell cycle arrest at the G2/M phase and subsequent activation of apoptosis, as well as inhibitory effects on the MAPK pathway and PI3K/AKT mediated cell migration in LLC1 cells. In the in vivo syngeneic model, exposure to GEGR resulted in suppressed growth of the LLC1 tumors, as well as inhibition of NF-κB signaling and their inflammatory cytokines. Taken together, our results provide novel evidence that exposure to GEGR induces activation of apoptosis, cell cycle arrest, and inhibition of cell migration via suppression of the MAPK, NF-κB and PI3K/AKT signaling pathways in LLC1 cells and the LLC1 syngeneic model.

Extract of Pogostemon cablin Possesses Potent Anticancer Activity against Colorectal Cancer Cells In Vitro and In Vivo

Pogostemon cablin (PCa), an herb used in traditional Chinese medicine, is routinely used in the amelioration of different types of gastrointestinal discomfort. However, the mechanisms underlying the cancer suppression activity of PCa in colorectal cancer (CRC) cells have yet to be clarified. The aim of this study was to investigate the anticancer effects of PCa, specifically the induction of apoptosis in CRC cells. The growth inhibition curve of CRC cells following exposure to PCa was detected by an MTT assay. Moreover, PCa combined with 5-FU revealed a synergic effect of decreased cell viability. PCa inhibited cell proliferation and induced cell cycle arrest at the G₀/G₁ phase and cell apoptosis through regulation of associated protein expression. An in vivo study showed that PCa suppressed the growth of CRC via induction of cell apoptosis with no significant change in body weight or organ histology. Our results demonstrated that PCa inhibits the growth of CRC cells and induces apoptosis in vitro and in vivo, which suggests the potential applicability of PCa as an anticancer agent.

Anti-Cancer Potential of Cannabinoids, Terpenes, and Flavonoids Present in Cannabis

In recent years, and even more since its legalization in several jurisdictions, cannabis and the endocannabinoid system have received an increasing amount of interest related to their potential exploitation in clinical settings. Cannabinoids have been suggested and shown to be effective in the treatment of various conditions. In cancer, the endocannabinoid system is altered in numerous types of tumours and can relate to cancer prognosis and disease outcome. Additionally, cannabinoids display anticancer effects in several models by suppressing the proliferation, migration and/or invasion of cancer cells, as well as tumour angiogenesis. However, the therapeutic use of cannabinoids is currently limited to the treatment of symptoms and pain associated with chemotherapy, while their potential use as cytotoxic drugs in chemotherapy still requires validation in patients. Along with cannabinoids, cannabis contains several other compounds that have also been shown to exert anti-tumorigenic actions. The potential anti-cancer effects of cannabinoids, terpenes and flavonoids, present in cannabis, are explored in this literature review.

Current translational potential and underlying molecular mechanisms of necroptosis

Cell death has a fundamental impact on the evolution of degenerative disorders, autoimmune processes, inflammatory diseases, tumor formation and immune surveillance. Over the past couple of decades extensive studies have uncovered novel cell death pathways, which are independent of apoptosis. Among these is necroptosis, a tightly regulated, inflammatory form of cell death. Necroptosis contribute to the pathogenesis of many diseases and in this review, we will focus exclusively on necroptosis in humans. Necroptosis is considered a backup mechanism of apoptosis, but the in vivo appearance of necroptosis indicates that both caspase-mediated and caspase-independent mechanisms control necroptosis. Necroptosis is regulated on multiple levels, from the transcription, to the stability and posttranslational modifications of the necrosome components, to the availability of molecular interaction partners and the localization of receptor-interacting serine/threonine-protein kinase 1 (RIPK1), receptor-interacting serine/threonine-protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL). Accordingly, we classified the role of more than seventy molecules in necroptotic signaling based on consistent in vitro or in vivo evidence to understand the molecular background of necroptosis and to find opportunities where regulating the intensity and the modality of cell death could be exploited in clinical interventions. Necroptosis specific inhibitors are under development, but >20 drugs, already used in the treatment of various diseases, have the potential to regulate necroptosis. By listing necroptosis-modulated human diseases and cataloging the currently available drug-repertoire to modify necroptosis intensity, we hope to kick-start approaches with immediate translational potential. We also indicate where necroptosis regulating capacity should be considered in the current applications of these drugs.

Subcritical Fluid Chromatography at Sub-Ambient Temperatures for the Chiral Resolution of Ketamine Metabolites with Rapid-Onset Antidepressant Effects

Chiral metabolites of ketamine exerting rapid-onset yet sustained antidepressant effects may be marketed directly in the future, but require chemo- and enantio-selective chromatographic methods for quality assurance and control. The chromatographic behavior of S-/R-ketamine, S-/R-norketamine, S-/R-dehydronorketamine, and (2R,6R)-/(2S,6S)-hydroxynorketamine in supercritical fluid chromatography (SFC) was investigated computationally and experimentally with the aim of identifying problematic pairs of enantiomers and parameters for chiral resolution. Retention on three different polysaccharide-based chiral stationary phases (Lux Amylose-2, i-Amylose-3, and i-Cellulose-5) provided new information on the significance of halogen atoms as halogen bond donors and hydrogen bond acceptors for enantioselectivity, which could be corroborated in silico by molecular docking studies. Modifiers inversely affected enantioselectivity and retention. Methanol yielded lower run times but superior chiral resolution compared to 2-propanol. Lower temperatures than those conventionally screened did not impair phase homogeneity but improved enantioresolution, at no cost to reproducibility. Thus, sub-ambient temperature subcritical fluid chromatography (SubFC), essentially low-temperature HPLC with subcritical CO2, was applied. The optimization of the SubFC method facilitated the chiral separation of ketamine and its metabolites, which was applied in combination with direct injection and online supercritical fluid extraction to determine the purity of pharmaceutical ketamine formulations for proof of concept.