In vitro antitumor effect of cucurbitacin E on human lung cancer cell line and its molecular mechanism

Metabolic profiling and antidiabetic potential of Oedogonium angustistomum, Ulothrix variabilis, and Mougeotia pulchella and their peptides targeting α-amylase and α-glucosidase: In vitro and in silico approaches

The present research aimed to examine the diabetes-fighting properties of three algal species: Oedogonium angustistomum, Ulothrix variabilis, and Mougeotia pulchella. The in vitro antidiabetic properties of these algae were investigated by α-amylase and α-glucosidase inhibition assays. The metabolites responsible for the inhibition of α-amylase (2QV4) and α-glucosidase (8YIE) were identified through molecular docking and molecular dynamic simulation in the Maestro V 13.2, Schrödinger suite. In the in vitro research, aqueous, methanol, and petroleum benzene-derived extracts of M. pulchella demonstrated significant inhibition of α-amylase and α-glucosidase, with IC50 values of 19.58, 16.67 μg/mL, and 16.43 μg/mL, respectively. In this research, approximately 62 chemical constituents belonging to various classes were identified by LC-MS. In the in-silico research, the peptides, namely 2-(S-Glutathionyl) acetyl glutathione, APGPR enterostatin, and endomorphine 2, were found to exhibit greater efficacy, with docking scores of -8.053, -8.564, and -7.653 kcal/mol respectively. Furthermore, molecular dynamics simulations demonstrated that the complexes exhibited a lower RMSD range of ≤2.8, indicating enhanced stability. Therefore, this study concludes that the peptides may serve as potential candidates for the development of anti-diabetic agents. However, further in vivo research is required to understand the mechanisms of action of peptides in diabetic experiments.

Cucurbitacin E elicits apoptosis in laryngeal squamous cell carcinoma by enhancing reactive oxygen species-regulated mitochondrial dysfunction and endoplasmic reticulum stress

Laryngeal squamous cell carcinoma (LSCC) is a prevalent head and neck neoplasm with escalating global morbidity and mortality rates. Despite the increasing burden of LSCC, the drugs currently approved for its treatment are limited. Therefore, it is necessary to identify novel and promising drugs that target LSCC. Cucurbitacin E (CuE) is a naturally oxygenated tetracyclic triterpenoid that suppresses several cancers. However, its anti-LSCC activity and the molecular mechanisms of action remain unclear. This study explored its impact on LSCC, revealing cell viability attenuation and apoptosis enhancement in vitro. Further investigations indicated that CuE significantly decreased mitochondrial membrane potential, thereby promoting cytochrome c release, increasing cleaved-Caspase 3 and cleaved-PARP levels, and triggering mitochondria-dependent apoptosis. Concurrently, exposure of LSCC cells to CuE enhanced endoplasmic reticulum (ER) stress, mobilized the protein kinase RNA-like endoplasmic reticulum kinase/initiation factor 2a/ATF4/C-EBP homologous protein pathway, and induced LSCC cell apoptosis. Finally, CuE markedly elevated intracellular reactive oxygen species (ROS) levels. When ROS were eliminated with N-acetylcysteine, CuE-mediated mitochondrial dysfunction, ER stress, and cell apoptosis were nearly abolished. Similar outcomes were observed in murine LSCC models. Together, these results highlight that CuE suppresses proliferation while triggering apoptosis in LSCC cells via ROS-regulated mitochondrial dysfunction and the ER stress pathway. Hence, CuE may serve as a promising candidate for LCSS treatment.

FOXM1 promotes the progression of non-small cell lung cancer by inhibiting miR-509-5p expression via binding to the miR-509-5p promoter region

Background

Forkhead box M1 (FOXM1) functions as a transcription factor and is consistently overexpressed in various cancers, including non-small-cell lung-, breast-, cervical-, and colorectal cancer. Its overexpression is associated with poor prognosis in patients with non-small-cell lung cancer, although the detailed mechanisms by which FOXM1 promotes the development of non-small-cell lung cancer remain unclear.

Objective

The mechanism of FOXM1 in migration, invasion, apoptosis, and viability of lung cancer cells was investigated.

Methods

Transwell assay, scratch test, and flow cytometry were employed to study the effects of FOXM1 on migration, invasion, and apoptosis in A549 cells. A quantitative polymerase chain reaction was used to determine the impact of FOXM1 on miR-509-5p expression in A549 cells. Dual-luciferase reporter gene assay and chromatin immunoprecipitation were adopted to investigate the molecular mechanisms of FOXM1 on miR-509-5p expression.

Results

FDI-6 (a FOXM1 inhibitor) reduced the protein abundance of FOXM1, thereby increasing the expression of miR-509-5p in A549 cells. Moreover, FDI-6 treatment significantly reduced migration, invasion, and viability of A549 cells while promoting cell apoptosis. Furthermore, miR-509-5p inhibitor obviously alleviated the biological effects of FDI-6 on A549 cells, suggesting that FOXM1 primarily exerted its cancer promoting effect by regulating miR-509-5p. Mechanistically, FOXM1 directly bound to the miR-509-5p promoter to inhibit miR-509-5p expression.

Conclusion

FOXM1 directly binds to the promoter region of miR-509-5p to form a negative feedback loop, thereby inhibiting miR-509-5p expression and promoting the development of non-small-cell lung cancer. This study is expected to complement research on the pathogenesis of non-small-cell lung cancer and promote the development of novel therapeutic targets for this disease.

Tragia plukenetii-Assisted Omega-Decenol as Potential Anticancer Agent: its Isolation, Characterization, and Validation

The second most common and lethal disease is lung cancer. To combat the negative effects of today's synthetic medications, natural phytomedicines are required. Tragia plukenetii is a medicinal plant native to India that belongs to the Euphorbiaceae family. The purpose of this research is to isolate bioactive compounds from T. plukenetii leaves and then test them for anticancer property. A single compound (CH: ME-20:80) was separated using TLC, and an RF value of 0.55 was determined. Spectral analyses utilizing UV-Visible Spectrophotometer and FT-IR were used to examine the absorbance and functional groups. ¹³C-NMR and ¹H-NMR studies revealed the tentative name of the purified phytochemical as omega-decenol (OD). Further antioxidant and anticancer properties of OD were tested for in vitro. In comparison to conventional L-ascorbic acid, the DPPH radical scavenging assay experiment yielded an IC₅₀ of 147.48 g/ml. With an IC₅₀ value of 24 µg/ml (Omega-decenol) and 32 µg/ml (doxorubicin), the MTT assay demonstrated the cytotoxic capability against the A549 lung cancer cell line. FACS revealed the cell cycle arrest of A549 at S phase compared to control with the high-dose IC₅₀ (250 µg/ml) of omega-decenol. Twelve major compounds were detected in the active fraction using GC-MS analysis, where n-hexadecanoic acid was found as a major. Omega-decenol showed good binding affinity against EGFR, amongst other receptors in the in silico docking study. This research reveals the potent anticancer activity of the isolated compound omega-decenol from T. plukenetii leaves and provides a key path to understanding the molecular interaction in anticancer aspects against adenocarcinoma.

Efficient expression of fusion human epidermal growth factor in tobacco chloroplasts

BACKGROUND

Chloroplast transformation is a robust technology for the expression of recombinant proteins. Various types of pharmaceutical proteins including growth factors have been reported in chloroplasts via chloroplast transformation approach at high expression levels. However, high expression of epidermal growth factor (EGF) in chloroplasts with the technology is still unavailable.

RESULTS

The present work explored the high-level expression of recombinant EGF, a protein widely applied in many clinical therapies, in tobacco chloroplasts. In this work, homoplastic transgenic plants expressing fusion protein GFP-EGF, which was composed of GFP and EGF via a linker, were generated. The expression of GFP-EGF was confirmed by the combination of green fluorescent observation and Western blotting. The achieved accumulation of the recombinant fusion GFP-EGF was 10.21 ± 0.27% of total soluble proteins (1.57 ± 0.05 g kg^- 1 of fresh leaf). The chloroplast-derived GFP-EGF was capable of increasing the cell viability of the NSLC cell line A549 and enhancing the phosphorylation level of the EGF receptor in the A549 cells.

CONCLUSION

The expression of recombinant EGF in tobacco chloroplasts via chloroplast transformation method was achieved at considerable accumulation level. The attempt gives a good example for the application of chloroplast transformation technology in recombinant pharmaceutical protein production.

Modulation of Cytoskeleton, Protein Trafficking, and Signaling Pathways by Metabolites from Cucurbitaceae, Ericaceae, and Rosaceae Plant Families

One promising frontier within the field of Medical Botany is the study of the bioactivity of plant metabolites on human health. Although plant metabolites are metabolic byproducts that commonly regulate ecological interactions and biochemical processes in plant species, such metabolites also elicit profound effects on the cellular processes of human and other mammalian cells. In this regard, due to their potential as therapeutic agents for a variety of human diseases and induction of toxic cellular responses, further research advances are direly needed to fully understand the molecular mechanisms induced by these agents. Herein, we focus our investigation on metabolites from the Cucurbitaceae, Ericaceae, and Rosaceae plant families, for which several plant species are found within the state of Florida in Hillsborough County. Specifically, we compare the molecular mechanisms by which metabolites and/or plant extracts from these plant families modulate the cytoskeleton, protein trafficking, and cell signaling to mediate functional outcomes, as well as a discussion of current gaps in knowledge. Our efforts to lay the molecular groundwork in this broad manner hold promise in supporting future research efforts in pharmacology and drug discovery.

Cucurbitacin I exhibits anticancer efficacy through induction of apoptosis and modulation of JAK/STAT3, MAPK/ERK, and AKT/mTOR signaling pathways in HepG2 cell line

Hepatocellular carcinoma is a common cancer type, especially among men. Although cucurbitacin I (CuI), widely found in plants belonging to the Ecballium elaterium (E. L) plant family, has been shown to have antitumorigenic properties in many cancer types, its anticancer effect, molecular mechanism, and apoptotic effect mediated by signal pathways on hepatocellular carcinoma have not been fully clarified. In the present study, we investigated the anticancer effect of CuI treated at different doses on the HepG2 cell line and the underlying mechanism in vitro. High-purity CuI was obtained from the E. elaterium plant with the aid of HPLC. The effects of this substance on the viability of cells were studied by the MTT assay. The effects of CuI on cell cycle progression and apoptosis were studied with flow cytometry. DNA breaks were analyzed by the Comet assay method. The proteins and genes involved in the JAK/STAT3, MAPK/ERK, and AKT/mTOR signaling pathways were investigated using Western blot and qRT-PCR, respectively. The results of this study demonstrated that CuI significantly reduced HepG2 cell growth in vitro, induced antiproliferation, and G2/M phase of the cell cycle was interrupted. PRACTICAL APPLICATIONS: CuI administration was shown to downregulate the levels of proteins in the PI3K/AKT/mTOR, MAPK, and JAK2/STAT3 cascades in HepG2 cells. CuI also reduced the expression of MAPK, STAT3, mTOR, JAK2, and Akt genes in different concentrations. DNA breaks are formed as a result of this effect. CuI, by reducing cell proliferation and promoting apoptosis, was found to have potential as a chemotherapeutic agent of hepatocellular carcinoma.

Apigenin-oxymatrine binary co-amorphous mixture: Enhanced solubility, bioavailability, and anti-inflammatory effect

Apigenin (APG) is a functional ingredient in many foods, but its poor water solubility results in low bioavailability. This study aimed at delivering APG and improving bioavailability by a food-friendly co-amorphous formulation of APG with oxymatrine (OMT). After preparation of co-amorphous mixture (CM), characterized by powder x-ray diffraction and thermal analysis. Then, the presence of hydrogen bonds was confirmed by vibrational spectroscopy and molecular dynamics simulation. Furthermore, phase solubility and solubility studies, as well as dissolution test indicated that complexation occurred between APG and OMT in solution, which significantly improved the solubility and dissolution of APG-OMT CM. Additionally, pharmacokinetics and biological activity indicated that APG-OMT CM exhibited higher oral bioavailability and anti-inflammatory effect than pure APG. These results suggest that APG-OMT CM may be great potential for application in functional food. Importantly, the study provides a promising delivery system to improve the bioavailability of hydrophobic food ingredients.

Cucurbitacin E inhibits cellular proliferation and induces apoptosis in melanoma by suppressing HSDL2 expression

BACKGROUND

Melanoma is among the most aggressive types of skin malignancy and can have an unpredictable clinical course. Exploration of novel therapeutic targets and their regulators remains essential for the prevention and treatment of melanoma.

METHODS

HSDL2 protein levels were examined by immunohistochemistry. The roles of HSDL2 in cell proliferation and apoptosis were identified by CCK-8 and colony formation assays. The function of HSDL2 in cell apoptosis was analysed by flow cytometry. Western blotting, cell proliferation and apoptosis and a xenograft tumour model were utilized to explore the inhibitory functions and mechanisms of CuE in melanoma.

RESULTS

HSDL2 is overexpressed in melanoma and promotes melanoma progression by activating the ERK and AKT pathways. CuE could inhibit the ERK and AKT pathways by decreasing HSDL2 expression; therefore, CuE could inhibit melanoma growth in vitro and in vivo.

CONCLUSION

HSDL2 may be a promising therapeutic target against melanoma, and CuE can inhibit melanoma by downregulating HSDL2 expression.

20(S)-Ginsenoside Rg3 Inhibits Lung Cancer Cell Proliferation by Targeting EGFR-Mediated Ras/Raf/MEK/ERK Pathway

Lung cancer is the leading cause of cancer death in the world and classified into non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). As tyrosine kinase inhibitors (TKIs), several triterpenoid saponins can target to epidermal growth factor receptor (EGFR), a widely used molecular therapeutic target, to exhibit remarkable anti-proliferative activities in cancer cells. As one of triterpenoid saponins, 20([Formula: see text])-ginsenoside Rg3 [20([Formula: see text])-Rg3] was confirmed to be an EGFR-TKI in this work. According to the quantitative real-time reverse transcription-PCR (qRT-PCR) and immunoblotting analysis, 20([Formula: see text])-Rg3 was certified to play a key role on EGFR/Ras/Raf/MEK/ERK signal pathway regulation. Our data demonstrated that 20([Formula: see text])-Rg3 might block the cell cycle at the G0/G1 phase by downregulating CDK2, Cyclin A2, and Cyclin E1. Molecular docking suggested that the combination of both hydrophobic and hydrogen-bonding interactions may help stabilizing the 20([Formula: see text])-Rg3-EGFR binding. Furthermore, their binding stability was assessed by molecular dynamics simulation. Taken together, these data provide the evidence that 20([Formula: see text])-Rg3 could prohibit A549 cell proliferation, probably by arresting the cell cycle at the G0/G1 phase via the EGFR/Ras/Raf/MEK/ERK pathway.