Targeting AKT/mTOR and Bcl-2 for Autophagic and Apoptosis Cell Death in Lung Cancer: Novel Activity of a Polyphenol Compound

A new benzoquinone and a new stilbenoid from Paphiopedilum exul (Ridl.) Rolfe

One new alkyl benzoquinone, paphionone (1), one new trans-stilbenoid, (E)-6,5'-dihydroxy-2,3'-dimethoxystilbene (2), and eight known stilbenoids and flavonoids (3-10) were isolated from the leaves and roots of Paphiopedilum exul (Orchidaceae). Their chemical structures were determined based on IR, ECD, MS and NMR analyses. Cytotoxicity of all isolated compounds towards human hepatocellular carcinoma (HepG2) cell line was examined in vitro by MTT assay. The para-hydroxybenzyl substituted stilbene 10 was potently cytotoxic to the cancer cells, with an IC50 value of 4.80 ± 1.10 μM (selectivity index = 20.83). All compounds were non-toxic to normal human embryo fibroblast (OUMS-36) cell line.

Preclinical Characterization of 22-(4'-Pyridinecarbonyl) Jorunnamycin A against Lung Cancer Cell Invasion and Angiogenesis via AKT/mTOR Signaling

Non-small-cell lung cancer (NSCLC), the most prevalent form of lung cancer, is associated with an unfavorable prognosis owing to its high rate of metastasis. Thus, the identification of new drugs with potent anticancer activities is essential to improve the clinical outcome of this disease. Marine organisms exhibit a diverse source of biologically active compounds with anticancer effects. The anticancer effects of jorunnamycin A (JA) derived from the Thai blue sponge (Xestospongia sp.) and 22-(4'-pyridinecarbonyl) jorunnamycin A (22-(4'-py)-JA), the semisynthetic derivative of JA, have been reported. The present study aimed to investigate the impact of 22-(4'-py)-JA on NSCLC metastasis using in vitro, in vivo, and in silico approaches. The JA derivative inhibited tumor cell invasion and tube formation in human umbilical vein endothelial cells (HUVECs). The computational analysis demonstrated strong and stable interactions between 22-(4'-py)-JA and the AKT protein. Further examinations into the molecular mechanisms revealed the suppression of AKT/mTOR/p70S6K signaling by 22-(4'-py)-JA, leading to the downregulation of matrix metalloproteinases (MMP-2 and MMP-9), hypoxia-inducible factor-1α (HIF-1α), and vascular endothelial growth factor (VEGF). Furthermore, 22-(4'-py)-JA suppressed in vivo metastasis by decreasing the number of colonies in the lung. These findings indicated the antimetastasis activity of 22-(4'-py)-JA, which might prove useful for further clinical applications.

Copper-instigated modulatory cell mortality mechanisms and progress in oncological treatment investigations

Copper, a transition metal, serves as an essential co-factor in numerous enzymatic active sites and constitutes a vital trace element in the human body, participating in crucial life-sustaining activities such as energy metabolism, antioxidation, coagulation, neurotransmitter synthesis, iron metabolism, and tetramer deposition. Maintaining the equilibrium of copper ions within biological systems is of paramount importance in the prevention of atherosclerosis and associated cardiovascular diseases. Copper induces cellular demise through diverse mechanisms, encompassing reactive oxygen species responses, apoptosis, necrosis, pyroptosis, and mitochondrial dysfunction. Recent research has identified and dubbed a novel regulatory cell death modality-"cuprotosis"-wherein copper ions bind to acylated proteins in the tricarboxylic acid cycle of mitochondrial respiration, resulting in protein aggregation, subsequent downregulation of iron-sulfur cluster protein expression, induction of proteotoxic stress, and eventual cell death. Scholars have synthesized copper complexes by combining copper ions with various ligands, exploring their significance and applications in cancer therapy. This review comprehensively examines the multiple pathways of copper metabolism, copper-induced regulatory cell death, and the current status of copper complexes in cancer treatment.

Effect of EGFR-TKIs combined with craniocerebral radiotherapy on the prognosis of EGFR-mutant lung adenocarcinoma patients with brain metastasis: A propensity-score matched analysis

Background and Purpose

Epidermal growth factor receptor (EGFR)-mutant lung cancers are associated with a high risk of developing brain metastases (BM). Craniocerebral radiotherapy is a cornerstone for the treatment of BM, and EGFR-TKIs act on craniocerebral metastases". However, whether EGFR-TKIs combined with craniocerebral radiotherapy can further increase the efficacy and improve the prognosis of patients is unclear. This study aimed to evaluate the difference in efficacy between targeted-therapy alone and targeted-therapy combined with radiotherapy in EGFR-mutant lung adenocarcinoma patients with BM.

Materials and Methods

A total of 291 patients with advanced non-small cell lung cancer (NSCLC) and EGFR mutations were enrolled in this retrospective cohort study. Propensity score matching (PSM) was conducted using a nearest-neighbor algorithm (1:1) to adjust for demographic and clinical covariates. Patients were divided into two groups: EGFR-TKIs alone and EGFR-TKIs combined with craniocerebral radiotherapy. Intracranial progression-free survival (iPFS) and overall survival (OS) were calculated. Kaplan-Meier analysis was used to compare iPFS and OS between the two groups. Brain radiotherapy included WBRT, local radiotherapy, and WBRT+Boost.

Results

The median age at diagnosis was 54 years (range: 28-81 years). Most patients were female (55.9%) and non-smokers (75.5%). Fifty-one pairs of patients were matched using PSM. The median iPFS for EGFR-TKIs alone (n=37) and EGFR-TKIs+craniocerebral radiotherapy (n=24) was 8.9 and 14.7 months, respectively. The median OS for EGFR-TKIs alone (n=52) and EGFR-TKIs+craniocerebral radiotherapy (n=52) was 32.1 and 45.3 months, respectively.

Conclusion

In EGFR-mutant lung adenocarcinoma patients with BM, targeted therapy combined with craniocerebral radiotherapy is an optimal treatment.

Nano-Based Drug Delivery of Polyphenolic Compounds for Cancer Treatment: Progress, Opportunities, and Challenges

Polyphenols and their derivates, a kind of natural product distributed in herb plants, vegetables, and fruits, are the most abundant antioxidants in the human diet and have been found to display cancer-preventative effects in several epidemiological studies. The scientific community has also validated the anti-cancer bioactivities and low toxicities of polyphenolic compounds, including flavones, tannins, phenolic acids, and anthocyanins, through in vitro and in vivo studies. However, the low stability, weak targeting ability, poor solubility, and low bioavailability of pure polyphenolic agents have significantly impaired their treatment efficacy. Nowadays, nano-based technology has been applied to surmount these restrictions and maximize the treatment efficacy of polyphenols. In this review, we summarize the advantages and related mechanisms of polyphenols in cancer treatment. Moreover, aiming at the poor solubility and low bioavailability of pure polyphenols in vivo, the advantages of nano-based delivery systems and recent research developments are highlighted. Herein, particular emphasis is mainly placed on the most widely used nanomaterials in the delivery of natural products, including liposomes, micelles, and nanogels. Finally, we present an overview and the challenges of future implementations of nano-based delivery systems of polyphenolic compounds in the cancer therapeutic field.

N,N'-Diarylurea Derivatives (CTPPU) Inhibited NSCLC Cell Growth and Induced Cell Cycle Arrest through Akt/GSK-3β/c-Myc Signaling Pathway

Lung cancer is one of the most common malignancies worldwide. Non-small-cell lung cancer (NSCLC) accounts for more than 80% of lung cancers, shows chemotherapy resistance, metastasis, and relapse. The phosphatidylinositol-3 kinase (PI3K)/Akt pathway has been implicated in the carcinogenesis and disease progression of NSCLC, suggesting that it may be a promising therapeutic target for cancer therapy. Although phenylurea derivatives have been reported as potent multiple kinase inhibitors, novel unsymmetrical N,N'-diarylurea derivatives targeting the PI3K/Akt pathway in NSCLC cells remain unknown.

METHODS

N,N'-substituted phenylurea derivatives CTPPU and CT-(4-OH)-PU were investigated for their anticancer proliferative activity against three NSCLC cell lines (H460, A549, and H292) by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide, colony formation, Hoechst33342/PI staining assays, and apoptosis analysis. The protein expressions of Akt pathway-related proteins in response to CTPPU or CT-(4-OH)-PU were detected by Western blot analysis. The Kyoto Encyclopedia of Genes and Genomes mapper was used to identify the possible signaling pathways in NSCLC treated with CTPPU. The cell cycle was analyzed by flow cytometry. Molecular docking was used to investigate the possible binding interaction of CTPPU with Akt, the mammalian target of rapamycin complex 2 (mTORC2), and PI3Ks. Immunofluorescence and Western blot analysis were used to validate our prediction.

RESULTS

The cytotoxicity of CTPPU was two-fold higher than that of CT-(4-OH)-PU for all NSCLC cell lines. Similarly, the non-cytotoxic concentration of CTPPU (25 µM) dramatically inhibited the colony formation of NSCLC cells, whereas its relative analog CT-(4-OH)-PU had no effect. Protein analysis revealed that Akt and its downstream effectors, namely, phosphorylated glycogen synthase kinase (GSK)-3β (Ser9), β-catenin, and c-Myc, were reduced in response to CTPPU treatment, which suggested the targeting of Akt-dependent pathway, whereas CT-(4-OH)-PU had no effect on such cell growth regulatory signals. CTPPU induced G1/S cell cycle arrest in lung cancer cells. Immunofluorescence revealed that CTPPU decreased p-Akt and total Akt protein levels, which implied the effect of the compound on protein activity and stability. Next, we utilized in silico molecular docking analysis to reveal the potential molecular targets of CTPPU, and the results showed that the compound could specifically bind to the allosteric pocket of Akt and three sites of mTORC2 (catalytic site, A-site, and I-site), with a binding affinity greater than that of reference compounds. The compound cannot bind to PI3K, an upstream regulator of the Akt pathway. The effect of CTPPU on PI3K and Akt was confirmed. This finding indicated that the compound could decrease p-Akt but caused no effect on p-PI3K.

CONCLUSIONS

The results indicate that CTPPU significantly inhibits NSCLC cell proliferation by inducing G1/S cell cycle arrest via the Akt/GSK-3β/c-Myc signaling pathway. Molecular docking revealed that CTPPU could interact with Akt and mTORC2 molecules with a high binding affinity. These data indicate that CTPPU is a potential novel alternative therapeutic approach for NSCLC.

Anticancer activity of β-Lapachone derivatives on human leukemic cell lines

β-lapachone is a 1,2-naphthoquinone of great therapeutic interest that induces cell death by autophagy and apoptosis in tumor cells due to oxidative stress increasing. However, its high toxicity in healthy tissues limits its clinical use, which stimulates the planning and synthesis of more selective analogs. The aim of this study was to investigate the cytotoxic activity of three thiosemicarbazones derived from β-lapachone (BV2, BV3 and BV5) in leukemia cells. Cytotoxicity tests were performed on tumor cells (HL-60, K562, K562-Lucena and MOLT-4) and normal peripheral blood mononuclear cells (PBMCs). Subsequently, the mode of action of compounds was accessed by optical microscopy, transmission electron microscopy or fluorescence microscopy. Flow cytometry analysis was performed to investigate apoptosis induction, cell cycle, DNA fragmentation and mitochondrial depolarization. All derivatives inhibited tumor cell growth after 72 h (IC₅₀ < 10 μM to all cell lines, including the resistant K562-Lucena) with less toxic effects in PBMC cells, being BV3 the most selective compound with selective index (SI) of 275 for HL-60; SI of 40 to K562; SI of 10 for MOLT-4 and SI of 50 to K562-Lucena compared to β-lapachone with SI of 18 to HL-60, SI of 3.7 to K562; SI of 2.4 to MOLT-4 and SI of 0.9 to K562-Lucena. In addition, the K562 or MOLT-4 cells treated with BV3 showed characteristics of both apoptosis and autophagy cell death, mainly by autophagy. These results demonstrate the potent cytotoxic effect of thiosemicarbazones derived from β-lapachone as promising anticancer drugs candidates, encouraging the continuity of in vivo tests.

Pennogenin-3-O-α-L-Rhamnopyranosyl-(1→2)-[α-L-Rhamnopyranosyl-(1→3)]-β-D-Glucopyranoside (Spiroconazol A) Isolated from Dioscorea bulbifera L. var. sativa Induces Autophagic Cell Death by p38 MAPK Activation in NSCLC Cells

In our previous study, we reported the isolation of pennogenin-3-O-α-L-rhamnopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→3)]-β-D-glucopyranoside (spiroconazol A), a steroidal saponin, from the flowers of Dioscorea bulbifera L. var. sativa. In the present study, we aimed to investigate the effects of spiroconazol A on autophagy and its underlying mechanisms in A549 and NCI-H358 human non-small cell lung cancer (NSCLC) cells. Spiroconazol A inhibited the proliferation of NSCLC cells in a concentration- and time-dependent manner. To determine the type of programmed cell death induced by spiroconazol A, we performed a characterization of apoptosis in spiroconazol A-treated A549 cells. Our results showed that spiroconazol A significantly suppressed A549 cell viability but did not influence cell apoptosis because phosphatidylserine and caspase activation were not detected. Furthermore, spiroconazol A treatment upregulated the expression of LC3-II and autophagy-related Beclin-1 protein, suggesting that spiroconazol A induces autophagy in A549 cells. Moreover, spiroconazol A activated the phosphorylation of p38 mitogen-activated protein kinase (MAPK) but did not affect the phosphorylation of Janus kinase or ERK1/2. Notably, SB203580, a p38 MAPK inhibitor, had a significant inhibitory effect on spiroconazol A-induced autophagic cell death in A549 cells. Our results indicated that spiroconazol A-induced autophagy is dependent on p38 MAPK signaling and has potential as a therapeutic target in NSCLC.

Functional Role of microRNAs in Regulating Cardiomyocyte Death

microRNAs (miRNA, miRs) play crucial roles in cardiovascular disease regulating numerous processes, including inflammation, cell proliferation, angiogenesis, and cell death. Herein, we present an updated and comprehensive overview of the functional involvement of miRs in the regulation of cardiomyocyte death, a central event in acute myocardial infarction, ischemia/reperfusion, and heart failure. Specifically, in this systematic review we are focusing on necrosis, apoptosis, and autophagy.

Effects of Polyphenols on ncRNAs in cancer - An update

In recent years, oncotherapy has received considerable attention concerning plant polyphenols. Increasing evidence suggests that due to the efficiency of polyphenols, they may have antitumor effects in various cancers. However, their regulatory structures remain elusive. Long non-coding RNAs (LncRNAs) have been identified in the regulation of various forms of tumorigenesis and tumor development. Long non-coding RNAs (LncRNAs) have recently emerged as regulatory eukaryotic transcripts and therapeutic targets with important and diverse functions in health and diseases. LncRNAs may be associated with the initiation, development, and progression of cancer. This review summarizes the research on the modulatory effects of LncRNAs and their roles in mediating cellular processes. The mechanisms of action of polyphenols underlying their therapeutic effects on cancers are also discussed. Based on our review, polyphenols might facilitate a significant epigenetic modification as part of their tissue-/cell-related biological effects. This finding may be attributed to their interaction with cellular signaling pathways involved in chronic diseases. Certain LncRNAs might be the target of specific polyphenols, and some critical signaling processes involved in the intervention of cancers might mediate the therapeutic roles of polyphenols. This article is protected by copyright. All rights reserved.

Artesunate Combined With Metformin Ameliorate on Diabetes-Induced Xerostomia by Mitigating Superior Salivatory Nucleus and Salivary Glands Injury in Type 2 Diabetic Rats via the PI3K/AKT Pathway

Polydipsia and xerostomia are the most common complications that seriously affect oral health in patients with diabetes. However, to date, there is no effective treatment for diabetic xerostomia. Recent studies have reported that artesunate (ART) and metformin (Met) improve salivary gland (SG) hypofunction in murine Sjögren's syndrome. Therefore, aim of this study was to investigate the effect and underlying mechanism of artesunate (ART) alone and in combination with metformin (Met) on hyposalivation in type 2 diabetes mellitus (T2DM) rats. T2DM rats were induced using a high-fat diet and streptozotocin. SPF male Sprague-Dawley rats were divided into the following five groups: normal control group, untreated diabetic group, ART-treated diabetic group (50 mg/kg), Met-treated diabetic group (150 mg/kg), and ART/Met co-treated diabetic group (50 mg/kg ART and 150 mg/kg Met). ART and Met were intragastrically administered daily for 4 weeks. The general conditions, diabetes parameters and serum lipids were evaluated after drug treatment. Furthermore, we observed changes in the central superior salivatory nucleus (SSN) and SG, and changes in the AQP5 expression, parasympathetic innervation (AChE and BDNF expression), and PI3K/AKT pathway- (p-AKT, and p-PI3K), apoptosis- (Bax, Bcl-2, and Caspase3), and autophagy- (LC3 and P62) related markers expression in T2DM rats after treatment. Our results showed that ART or Met alone and ART/Met combination attenuated a range of diabetic symptoms, including weight loss, urine volume increase, water consumption increase, hyperglycemia, insulin resistance, glucose intolerance and dyslipidemia. More importantly, we found that these three treatments, especially ART/Met combination, mitigated hyposalivation in the T2DM rats via improving the central SSN and SGs damage in hyperglycemia. Our data also indicated that ART/Met attenuated SG damage though regulating the PI3K/Akt pathway to inhibit apoptosis and autophagy of SGs in the T2DM rats. Moreover, ART/Met preserved parasympathetic innervation (AChE and BDNF expression) in SGs to alleviate diabetes-induced hyposalivation likely through rescuing central SSN damage. Taken together, these findings might provide a novel rationale and treatment strategy for future treatment of diabetes-induced xerostomia in the clinic.

Metal enriched quasi-ultrafine particles from stainless steel gas metal arc welding induced genetic and epigenetic alterations in BEAS-2B cells

Recent evidence has supported welding fume (WF)-derived ultrafine particles (UFP) could be the driving force of their adverse health effects. However, UFP have not yet been extensively studied and are currently not included in present air quality standards/guidelines. Here, attention was focused on the underlying genetic and epigenetic mechanisms by which the quasi-UFP (Q-UFP, i.e., ≤ 0.25 μm) of the WF emitted by gas metal arc welding-stainless steel (GMAW-SS) exert their toxicity in human bronchial epithelial BEAS-2B cells. The Q-UFP under study showed a monomodal size distribution in number centered on 104.4 ± 52.3 nm and a zeta potential of -13.8 ± 0.3 mV. They were enriched in Fe > Cr > Mn > Si, and displayed a relatively high intrinsic oxidative potential. Dose-dependent activation of nuclear factor erythroid 2-related factor 2 and nuclear factor-kappa B signaling pathway, glutathione alteration, and DNA, protein and lipid oxidative damage were reported in BEAS-2B cells acutely (1.5 and 9 μg/cm², 24 h) or repeatedly (0.25 and 1.5 μg/cm², 3 × 24 h) exposed to Q-UFP (p < 0.05). Alterations of the Histone H3 acetylation were reported for any exposure (p < 0.05). Differentially regulated miRNA and mRNA indicated the activation of some critical cell signaling pathways related to oxidative stress, inflammation, and cell cycle deregulation towards apoptosis. Taken together, these results highlighted the urgent need to better evaluate the respective toxicity of the different metals and to include the Q-UFP fraction of WF in current air quality standards/guidelines relevant to the occupational settings.