Cellular Distribution and Ultrastructural Changes in HaCaT Cells, Induced by Podophyllotoxin and Its Novel Fluorescent Derivative, Supported by the Molecular Docking Studies.

Podophyllotoxin (PPT) is an active pharmaceutical ingredient (API) with established antitumor potential. However, due to its systemic toxicity, its use is restricted to topical treatment of anogenital warts. Less toxic PPT derivatives (e.g., etoposide and teniposide) are used intravenously as anticancer agents. PPT has been exploited as a scaffold of new potential therapeutic agents; however, fewer studies have been conducted on the parent molecule than on its derivatives. We have undertaken a study of ultrastructural changes induced by PPT on HaCaT keratinocytes. We have also tracked the intracellular localization of PPT using its fluorescent derivative (PPT-FL). Moreover, we performed molecular docking of both PPT and PPT-FL to compare their affinity to various binding sites of tubulin. Using the Presto blue viability assay, we established working concentrations of PPT in HaCaT cells. Subsequently, we have used selected concentrations to determine PPT effects at the ultrastructural level. Dynamics of PPT distribution by confocal microscopy was performed using PPT-FL. Molecular docking calculations were conducted using Glide. PPT induces a time-dependent cytotoxic effect on HaCaT cells. Within 24 h, we observed the elongation of cytoplasmic processes, formation of cytoplasmic vacuoles, progressive ER stress, and shortening of the mitochondrial long axis. After 48 h, we noticed disintegration of the cell membrane, progressive vacuolization, apoptotic/necrotic vesicles, and a change in the cell nucleus's appearance. PPT-FL was detected within HaCaT cells after ~10 min of incubation and remained within cells in the following measurements. Molecular docking confirmed the formation of a stable complex between tubulin and both PPT and PPT-FL. However, it was formed at different binding sites. PPT is highly toxic to normal human keratinocytes, even at low concentrations. It promptly enters the cells, probably via endocytosis. At lower concentrations, PPT causes disruptions in both ER and mitochondria, while at higher concentrations, it leads to massive vacuolization with subsequent cell death. The novel derivative of PPT, PPT-FL, forms a stable complex with tubulin, and therefore, it is a useful tracker of intracellular PPT binding and trafficking.

Podophyllic Aldehyde, a Podophyllotoxin Derivate, Elicits Different Cell Cycle Profiles Depending on the Tumor Cell Line: A Systematic Proteomic Analysis.

When new antitumor therapy drugs are discovered, it is essential to address new target molecules from the point of view of chemical structure and to carry out efficient and systematic evaluation. In the case of natural products and derived compounds, it is of special importance to investigate chemomodulation to further explore antitumoral pharmacological activities. In this work, the compound podophyllic aldehyde, a cyclolignan derived from the chemomodulation of the natural product podophyllotoxin, has been evaluated for its viability, influence on the cell cycle, and effects on intracellular signaling. We used functional proteomics characterization for the evaluation. Compared with the FDA-approved drug etoposide (another podophyllotoxin derivative), we found interesting results regarding the cytotoxicity of podophyllic aldehyde. In addition, we were able to observe the effect of mitotic arrest in the treated cells. The use of podophyllic aldehyde resulted in increased cytotoxicity in solid tumor cell lines, compared to etoposide, and blocked the cycle more successfully than etoposide. High-throughput analysis of the deregulated proteins revealed a selective antimitotic mechanism of action of podophyllic aldehyde in the HT-29 cell line, in contrast with other solid and hematological tumor lines. Also, the apoptotic profile of podophyllic aldehyde was deciphered. The cell death mechanism is activated independently of the cell cycle profile. The results of these targeted analyses have also shown a significant response to the signaling of kinases, key proteins involved in signaling cascades for cell proliferation or metastasis. Thanks to this comprehensive analysis of podophyllic aldehyde, remarkable cytotoxic, antimitotic, and other antitumoral features have been discovered that will repurpose this compound for further chemical transformations and antitumoral analysis.

PROTAC EZH2 degrader-1 overcomes the resistance of podophyllotoxin derivatives in refractory small cell lung cancer with leptomeningeal metastasis.

BACKGROUND: Leptomeningeal metastasis (LM) of small cell lung cancer (SCLC) is a highly detrimental occurrence associated with severe neurological disorders, lacking effective treatment currently. Proteolysis-targeting chimeric molecules (PROTACs) may provide new therapeutic avenues for treatment of podophyllotoxin derivatives-resistant SCLC with LM, warranting further exploration. METHODS: The SCLC cell line H128 expressing luciferase were mutated by MNNG to generate H128-Mut cell line. After subcutaneous inoculation of H128-Mut into nude mice, H128-LM and H128-BPM (brain parenchymal metastasis) cell lines were primarily cultured from LM and BPM tissues individually, and employed to in vitro drug testing. The SCLC-LM mouse model was established by inoculating H128-LM into nude mice via carotid artery and subjected to in vivo drug testing. RNA-seq and immunoblotting were conducted to uncover the molecular targets for LM. RESULTS: The SCLC-LM mouse model was successfully established, confirmed by in vivo live imaging and histological examination. The upregulated genes included EZH2, SLC44A4, VEGFA, etc. in both BPM and LM cells, while SLC44A4 was particularly upregulated in LM cells. When combined with PROTAC EZH2 degrader-1, the drug sensitivity of cisplatin, etoposide (VP16), and teniposide (VM26) for H128-LM was significantly increased in vitro. The in vivo drug trials with SCLC-LM mouse model demonstrated that PROTAC EZH2 degrader-1 plus VM26 or cisplatin/ VP16 inhibited H128-LM tumour significantly compared to VM26 or cisplatin/ VP16 alone (P < 0.01). CONCLUSION: The SCLC-LM model effectively simulates the pathophysiological process of SCLC metastasis to the leptomeninges. PROTAC EZH2 degrader-1 overcomes chemoresistance in SCLC, suggesting its potential therapeutic value for SCLC LM.

Deoxypodophyllotoxin Induces ROS-Mediated Apoptosis by Modulating the PI3K/AKT and p38 MAPK-Dependent Signaling in Oral Squamous Cell Carcinoma.

Deoxypodophyllotoxin (DPT), a naturally occurring flavonolignan, possesses several pharmacological properties, including anticancer property. However, the mechanisms underlying DPT mode of action in oral squamous cell carcinoma (OSCC) remain unknown. This study aimed to investigate the anticancer effects of DPT on OSCC and the underlying mechanisms. Results of the MTT assay revealed that DPT significantly reduced the cell viability in a time- and dose-dependent manner. Flow cytometry analysis revealed that DPT induces apoptosis in OSCC cells in a dose-dependent manner. Moreover, DPT enhanced the production of mitochondrial reactive oxygen species (ROS) in OSCC cells. Mechanistically, DPT induced apoptosis in OSCC cells by suppressing the PI3K/AKT signaling pathway while activating the p38 MAPK signaling to regulate the expression of apoptotic proteins. Treatment with SC79, an AKT activator, reversed the effects of DPT on AKT signaling in OSCC cells. Taken together, these results provide the basis for the use of DPT in combination with conventional chemotherapy for the treatment of oral cancer.

Picropodophyllin Inhibits the Proliferation of Human Prostate Cancer DU145 and LNCaP Cells via ROS Production and PI3K/AKT Pathway Inhibition.

The reactive oxygen species (ROS) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway play critical roles in the pathogenesis of prostate cancer by modulating cell proliferation. Picropodophyllin (PPP), an inhibitor of the insulin-like growth factor 1 receptor (IGF-1R), exerts significant antitumor effects via the PI3K/AKT signaling pathway. However, the effects of PPP on prostate cancer via ROS production and the PI3K/AKT signaling pathway remain elusive. Herein, we focused on examining the antitumor effects of PPP on DU145 and LNCaP human prostate cancer cells to determine the possible molecular mechanism. Our data indicated that the inhibitory effect of PPP on the proliferation of DU145 and LNCaP human prostate cancer cells was mediated by apoptosis induction and cell cycle blockade. Furthermore, PPP significantly influenced the expression of apoptosis-related, cell cycle, ROS production, and PI3K/AKT signaling proteins. These findings suggest that PPP can induce cell cycle arrest and apoptosis via the production of ROS and inhibition of PI3K/AKT signaling pathway, thereby suppressing the proliferation of prostate cancer cells.

A comprehensive insight into the antineoplastic activities and molecular mechanisms of deoxypodophyllotoxin: Recent trends, challenges, and future outlook.

Lignans constitute an important group of polyphenols, which have been demonstrated to potently suppress cancer cell proliferation. Numerous in vitro and in vivo studies indicate that deoxypodophyllotoxin as a natural lignan possesses potent anticancer activities against various types of human cancer. The purpose of current review is to provide the reader with the latest findings in understanding the anticancer effects and molecular mechanisms of deoxypodophyllotoxin. This review comprehensively describes the influence of deoxypodophyllotoxin on signaling cascades and molecular targets implicated in cancer cell proliferation and invasion. A number of various signaling molecules and pathways, including apoptosis, necroptosis, cell cycle, angiogenesis, vascular disruption, ROS, MMPs, glycolysis, and microtubules as well as NF-κB, PI3K/Akt/mTOR, and MAPK cascades have been reported to be responsible for the anticancer activities of deoxypodophyllotoxin. The results of present review suggest that the cyclolignan deoxypodophyllotoxin can be developed as a novel and potent anticancer agent, especially as an alternative option for treatment of resistant tumors to chemotherapy.

2, 4, 5-Trideoxyhexopyranosides Derivatives of 4'-Demethylepipodophyllotoxin: De novo Synthesis and Anticancer Activity.

BACKGROUND: Podophyllotoxin is a natural lignan which possesses anticancer and antiviral activities. Etoposide and teniposide are semisynthetic glycoside derivatives of podophyllotoxin and are increasingly used in cancer medicine. OBJECTIVE: The present work aimed to design and synthesize a series of 2, 4, 5-trideoxyhexopyranosides derivatives of 4'-demethylepipodophyllotoxin as novel anticancer agents. METHODS: A divergent de novo synthesis of 2, 4, 5-trideoxyhexopyranosides derivatives of 4'- demethylepipodophyllotoxin has been established via palladium-catalyzed glycosylation. The abilities of synthesized glycosides to inhibit the growth of A549, HepG2, SH-SY5Y, KB/VCR and HeLa cancer cells were investigated by MTT assay. Flow cytometric analysis of cell cycle with propidium iodide DNA staining was employed to observe the effect of compound 5b on cancer cell cycle. RESULTS: Twelve D and L monosaccharide derivatives 5a-5l have been efficiently synthesized in three steps from various pyranone building blocks employing de novo glycosylation strategy. Dmonosaccharide 5b showed the highest cytotoxicity on five cancer cell lines with the IC50 values ranging from 0.9 to 6.7 µM. It caused HepG2 cycle arrest at G2/M phase in a concentrationdependent manner. CONCLUSION: The present work leads to the development of novel 2, 4, 5-trideoxyhexopyranosides derivatives of 4'-demethylepipodophyllotoxin. The biological results suggest that the replacement of the glucosyl moiety of etoposide with 2, 4, 5-trideoxyhexopyranosyl is favorable to their cytotoxicity. D-monosaccharide 5b was observed to cause HepG2 cycle arrest at the G2/M phase in a concentration- dependent manner.

Selective elimination of CML stem/progenitor cells by picropodophyllin in vitro and in vivo is associated with p53 activation.

Chronic myeloid leukemia (CML) is a hematologic malignancy originating from BCR-ABL oncogene-transformed hematopoietic stem cells (HSCs) known as leukemia stem cells (LSCs). Therefore, targeting LSCs is of primary importance to eradicate CML. The present study demonstrates that picropodophyllin (PPP) effectively induces apoptosis and inhibits colony formation in CML stem/progenitor cells as well as quiescent CML progenitors resistant to imatinib therapy, while sparing normal hematopoietic cells in vitro. Administration of PPP in vivo markedly diminishes CML stem/progenitor cells in a transgenic mouse model of CML by inhibition of cell proliferation and enhancement of apoptosis in LSK cells, and significantly improves survival of CML mice. Furthermore, PPP treatment preferentially leads to transcriptional activation of p53 in CML but not normal CD34+ cells, upregulation of p53 protein in LSCs-enriched Sca-1+ cells from CML mice, and increased phosphorylation of p53 and upregulation of Bax protein in Ku812 cells. These results suggest that the inhibitory effects of PPP on CML stem/progenitor cells are associated with selective activation of p53 pathway and propose that PPP is a potent agent that selectively targets CML LSCs, and may be of value in the CML therapy.

Synthesis of (-)-deoxypodophyllotoxin and (-)-epipodophyllotoxin via a multi-enzyme cascade in E. coli.

BACKGROUND: The aryltetralin lignan (-)-podophyllotoxin is a potent antiviral and anti-neoplastic compound that is mainly found in Podophyllum plant species. Over the years, the commercial demand for this compound rose notably because of the high clinical importance of its semi-synthetic chemotherapeutic derivatives etoposide and teniposide. To satisfy this demand, (-)-podophyllotoxin is conventionally isolated from the roots and rhizomes of Sinopodophyllum hexandrum, which can only grow in few regions and is now endangered by overexploitation and environmental damage. For these reasons, targeting the biosynthesis of (-)-podophyllotoxin precursors or analogues is fundamental for the development of novel, more sustainable supply routes. RESULTS: We recently established a four-step multi-enzyme cascade to convert (+)-pinoresinol into (-)-matairesinol in E. coli. Herein, a five-step multi-enzyme biotransformation of (-)-matairesinol to (-)-deoxypodophyllotoxin was proven effective with 98 % yield at a concentration of 78 mg/L. Furthermore, the extension of this cascade to a sixth step leading to (-)-epipodophyllotoxin was evaluated. To this end, seven enzymes were combined in the reconstituted pathway involving inter alia three plant cytochrome P450 monooxygenases, with two of them being functionally expressed in E. coli for the first time. CONCLUSIONS: Both, (-)-deoxypodophyllotoxin and (-)-epipodophyllotoxin, are direct precursors to etoposide and teniposide. Thus, the reconstitution of biosynthetic reactions of Sinopodophyllum hexandrum as an effective multi-enzyme cascade in E. coli represents a solid step forward towards a more sustainable production of these essential pharmaceuticals.

Enhanced Aryltetralin Lignans Production in Linum Adventi-Tious Root Cultures.

Lignans are the main secondary metabolites synthetized by Linum species as plant defense molecules. They are also valuable for human health, in particular, for their potent antiviral and antineoplastic properties. In this study, the adventitious root cultures of three Linum species (L. flavum, L. mucronatum and L. dolomiticum) were developed to produce aryltetralin lignans. The effect of two elicitors, methyl jasmonate and coronatine, on aryltetralin lignans production was also evaluated. The adventitious root cultures from L. dolomiticum were obtained and analyzed for the first time and resulted as the best producer for all the aryltetralins highlighted in this system: Podophyllotoxin, 6-methoxypodophyllotoxin and 6-methoxypodophyllotoxin-7-O-ß-glucoside, the last showing a productivity of 92.6 mg/g DW. The two elicitors differently affected the production of the 6-methoxypodophyllotoxin and 6-methoxypodophyllotoxin-7-O-ß-glucoside.

Picropodophyllotoxin Induces G1 Cell Cycle Arrest and Apoptosis in Human Colorectal Cancer Cells via ROS Generation and Activation of p38 MAPK Signaling Pathway.

Picropodophyllotoxin (PPT), an epimer of podophyllotoxin, is derived from the roots of Podophyllum hexandrum and exerts various biological effects, including anti-proliferation activity. However, the effect of PPT on colorectal cancer cells and the associated cellular mechanisms have not been studied. In the present study, we explored the anticancer activity of PPT and its underlying mechanisms in HCT116 cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to monitor cell viability. Flow cytometry was used to evaluate cell cycle distribution, the induction of apoptosis, the level of reactive oxygen species (ROS), assess the mitochondrial membrane potential (Δψm), and multi-caspase activity. Western blot assays were performed to detect the expression of cell cycle regulatory proteins, apoptosis-related proteins, and p38 MAPK (mitogen-activated protein kinase). We found that PPT induced apoptosis, cell cycle arrest at the G1 phase, and ROS in the HCT116 cell line. In addition, PPT enhanced the phosphorylation of p38 MAPK, which regulates apoptosis and PPT-induced apoptosis. The phosphorylation of p38 MAPK was inhibited by an antioxidant agent (N-acetyl-L-cysteine, NAC) and a p38 inhibitor (SB203580). PPT induced depolarization of the mitochondrial inner membrane and caspase-dependent apoptosis, which was attenuated by exposure to Z-VAD-FMK. Overall, these data indicate that PPT induced G1 arrest and apoptosis via ROS generation and activation of the p38 MAPK signaling pathway.

Autophagy induction by IGF1R inhibition with picropodophyllin and linsitinib.

Induction of macroautophagy (hereafter termed autophagy) is a strategy to improve the outcome of antineoplastic therapies by facilitating the induction of immunogenic cancer cell death and the consequent immune recognition of malignant cells. We analyzed 65,000 distinct compounds by means of a phenotypic discovery platform for autophagy induction and identified the IGF1R (insulin like growth factor 1 receptor) inhibitor picropodophyllin (PPP) as a potent inducer of autophagic flux. We found that PPP acts on-target, as an inhibitor of the tyrosine kinase activity of IGF1R and enhances the release of adenosine triphosphate, ATP, from stressed and dying cancer cells in vitro, thereby improving the therapeutic efficacy of chemoimmunotherapy in cancer-bearing mice. This PPP effect was phenocopied by another IGF1R inhibitor, linsitinib. Moreover, in human triple-negative breast cancer, phosphorylation of IGF1R correlates with reduced autophagy, an unfavorable local immune profile and poor prognosis. In summary, IGF1R inhibition may constitute a novel strategy for the treatment of cancer in the context of chemoimmunotherapy.

PICT1 is critical for regulating the Rps27a-Mdm2-p53 pathway by microtubule polymerization inhibitor against cervical cancer.

In our previous study, it showed that P-3F, a podophyllotoxin derivative, causes the increased level of p53 expression by enhancing p53 stability, resulting from blockage of the Mdm2-p53 feedback loop via nucleolus-to-nucleoplasm translocation of Rps27a in human cervical cancer HeLa cell line. However, the mechanism of regulating Rps27a localization remains to be studied. In the current study, it has been demonstrated that the level of protein interacting with carboxyl terminus 1 (PICT1), originally identified as a tumor suppressor, was decreased in a concentration-dependent manner in response to P-3F, leading to inhibition of human cervical cancer cell lines proliferation. Also remarkably, reduction of serine phosphorylation of STMN1 at position 16 induced by P-3F was required in the downregulation of PICT1, in which p53 activity was likely to be directly involved. Note as well that, PICT1 also played an important role in p53 stability enhancement by inhibiting Mdm2-mediated p53 ubiquitination due to Rps27a translocation from the nucleolus to the nucleoplasm to interact with Mdm2 following treatment with P-3F. Collectively, these findings indicated that P-3F, a microtubule polymerization inhibitor, promotes the decreased level of PICT1 expression, which is critical for regulating the Rps27a-Mdm2-p53 pathway against cervical cancer.

Triazole/thiadiazole substituted 4'-demethylepipodophyllotoxin derivatives induced apoptosis in HeLa cells by up-regulating TMEM133.

Heterocycle modification has been widely and successfully employed in the antitumor drugs. However, the different antitumor efficacy was corelated with the heterocycle substituted, and the genetic mechanism underlying these effects has not been elucidated. In this study, the intrinsic regularity between different types of heterocycle-substituted DMEP derivative compounds and the mechanisms of their antitumor activity was preliminarily disclosed. Triazole/thiadiazole substituted 4'-demethylepipodophyllotoxin derivatives induced more severe DNA damage and higher levels of 26S proteasomal Topo IIß degradation, though inhibited the recruition of γH2AX to resist the DNA damage. The reduced DNA repair led to higher up-regulation of cell cycle arrest proteins, and ultimately DNA damage mediated-ATM/ATR apoptotic pathways and specifically activated DNA damage response gene TMEM133, which induced apoptosis through up-regulation of G2/M cell cycle arrest-related genes. Over-expression and knock-out of TMEM133 demonstrated that TMEM133 is essential for inhibition of the tumor cell growth during treatment with triazole/thiadiazole substituted 4'-demethylepipodophyllotoxin derivatives.

Podophyllotoxin: History, Recent Advances and Future Prospects.

Podophyllotoxin, along with its various derivatives and congeners are widely recognized as broad-spectrum pharmacologically active compounds. Etoposide, for instance, is the frontline chemotherapeutic drug used against various cancers due to its superior anticancer activity. It has recently been redeveloped for the purpose of treating cytokine storm in COVID-19 patients. Podophyllotoxin and its naturally occurring congeners have low bioavailability and almost all these initially discovered compounds cause systemic toxicity and development of drug resistance. Moreover, the production of synthetic derivatives that could suffice for the clinical limitations of these naturally occurring compounds is not economically feasible. These challenges demanded continuous devotions towards improving the druggability of these drugs and continue to seek structure-optimization strategies. The discovery of renewable sources including microbial origin for podophyllotoxin is another possible approach. This review focuses on the exigency of innovation and research required in the global R&D and pharmaceutical industry for podophyllotoxin and related compounds based on recent scientific findings and market predictions.

Deoxypodophyllotoxin Inhibits Cell Growth and Induces Apoptosis by Blocking EGFR and MET in Gefitinib-Resistant Non-Small Cell Lung Cancer.

As one of the major types of lung cancer, non-small cell lung cancer (NSCLC) accounts for the majority of cancer-related deaths worldwide. Treatments for NSCLC includes surgery, chemotherapy, and targeted therapy. Among the targeted therapies, resistance to inhibitors of the epidermal growth factor receptor (EGFR) is common and remains a problem to be solved. MET (hepatocyte growth factor receptor) amplification is one of the major causes of EGFR-tyrosine kinase inhibitor (TKI) resistance. Therefore, there exists a need to find new and more efficacious therapies. Deoxypodophyllotoxin (DPT) extracted from Anthriscus sylvestris roots exhibits various pharmacological activities including anti-inflammation and anti-cancer effects. In this study we sought to determine the anti-cancer effects of DPT on HCC827GR cells, which are resistant to gefitinib (EGFR-TKI) due to regulation of EGFR and MET and their related signaling pathways. To identify the direct binding of DPT to EGFR and MET, we performed pull-down, ATP-binding, and kinase assays. DPT exhibited competitive binding with ATP against the network kinases EGFR and MET and reduced their activities. Also, DPT suppressed the expression of p-EGFR and p-MET as well as their downstreat proteins p-ErbB3, p-AKT, and p-ERK. The treatment of HCC827GR cells with DPT induced high ROS generation that led to endoplasmic-reticulum stress. Accordingly, loss of mitochondrial membrane potential and apoptosis by multi-caspase activation were observed. In conclusion, these results demonstrate the apoptotic effects of DPT on HCC827GR cells and signify the potential of DPT to serve as an adjuvant anti-cancer drug by simultaneously inhibiting EGFR and MET.

Novel podophyllotoxin and benzothiazole derivative induces transitional morphological and functional changes in HaCaT cells.

Podophyllotoxin (PPT) is an antimitotic drug used topically in the treatment of anogenital warts. Due to its toxicity it cannot be administered systemically as an anticancer agent. However, modified PPT derivatives such as etoposide and teniposide are used clinically as systemic agents. Thus, we invented novel PPT derivative KL3 that was synthesized by photocyclization. Earlier we have shown that KL3 has an anticancer effect in various cell lines. Here we compared the toxicity of KL3 vs PPT on non-cancerous normal human keratinocytes (HaCaT) and peripheral blood mononuclear cells (PBMC) showing that KL3 is less toxic than PPT to non-cancerous cells. At concentrations that neither induced cell death, nor affected cell cycle, KL3 in HaCaT cells evoked transient ultrastructural features of ER stress, swelling of mitochondria and elongation of cytoplasmic processes. Those changes partially reversed with prolonged incubation while features of autophagy were induced. PPT in equivalent concentrations induced HaCaT cell death by cell cycle arrest, intrinsic apoptosis and finally disintegration of cell membranes followed by secondary necrosis. In conclusion, we show that the KL3 derivative of PPT in contrast to PPT allows repair of normal keratinocytes and triggers mechanisms that restore non-tumor cell homeostasis.

Recent Advances in the Application of Podophyllotoxin Derivatives to Fight Against Multidrug-Resistant Cancer Cells.

Podophyllotoxins, including epipodophyllotoxin derivatives, can act on a diverse array of drug targets in cancer cells and thus possess potent activity against various forms of cancer cell lines, including drug-resistant forms. Moreover, several podophyllotoxin derivatives represented by etoposide and teniposide, have already been approved for cancer therapy, demonstrating podophyllotoxin moiety as a useful pharmacophore for the discovery of novel anticancer agents. This review reports the recent advances in the exploitation of podophyllotoxin derivatives to fight against multidrug-resistant cancer cells. The mechanism of action and structure-activity relationship (SAR) studies are also highlighted.

Inhibition of SNCG suppresses the proliferation of lung cancer cells induced by high glucose.

Lung cancer is the most common cancer type worldwide and the leading cause of cancer-related mortality. Diabetes is closely associated with the occurrence, development and prognosis of lung cancer. Therefore, the present study aimed to investigate whether SNCG could affect the proliferation of lung cancer cells induced by high glucose. Lung cancer cells induced by high glucose simulated the pathologies of patients with lung cancer with diabetes in vitro. The proliferation of HBE cells and lung cancer cells after transfection and treatment of glucose was detected using Cell Counting Kit-8 assay. The mRNA expression levels of synuclein γ (SNCG), insulin-like growth factor 1 (IGF-1) and IGF-1 receptor (IGF-1R) in HBE cells and lung cancer cells alone, or cells induced by high glucose were analyzed via reverse transcription-quantitative (RT-q)PCR analysis. Moreover RT-qPCR analysis was used to determine the transfection efficiencies. The clone formation ability, migration and inflammation of lung cancer cells after high glucose induction and transfection were detected using clone formation, wound healing and ELISA assays. The protein expression levels of SNCG, IGF-1, IGF-1R, ERK 1/2, phosphorylated (p)-ERK1/2 and JNK in lung cancer cells after high glucose induction and transfection were determined using western blot analysis. The results suggested that high glucose significantly promoted the proliferation of A549, NCI-H1975 and SK-MES-1 cells at 24 and 48 h, as well as upregulated the expression levels of SNCG, IGF-1 and IGF-1R. Knockdown of SNCG suppressed the proliferation, clone formation ability and migration, but alleviated inflammation in A549 cells induced by high glucose. Knockdown of SNCG suppressed the expression levels of SNCG, IGF-1, IGF-1R, ERK1/2 and p-ERK1/2, while it promoted JNK expression in A549 cells induced by high glucose. The effect of AXL1717 (an IGF-1R inhibitor) treatment on cells was consistent with that of SNCG knockdown. In conclusion, inhibition of SNCG suppresses proliferation of lung cancer cells induced by high glucose.

Prognostic value of pretreatment plasma D-dimer level in dogs with intermediate to high-grade non-Hodgkin lymphoma.

Pretreatment D-dimer levels have been reported to predict survival in several types of malignancies in human patients. The objective of this study was to evaluate the prognostic value of pretreatment D-dimer level in dogs with intermediate to high-grade non-Hodgkin lymphoma (NHL). In a prospective, randomized, double-blind study of F14512 vs etoposide phosphate, we assessed the prognostic value of pretreatment plasma D-dimer level in 48 client-owned dogs diagnosed with intermediate to high-grade NHL. The correlation between pretreatment plasma D-dimer level and various clinical features, progression-free survival (PFS) and overall survival (OS) was analysed. The median value of pretreatment plasma D-dimer level was 0.4 µg/mL (range: 0.1-14.3 µg/mL). High pretreatment plasma D-dimer level (>0.5 µg/mL) was detected in 44% (21/48) of dogs. High D-dimer levels were not correlated with naive vs relapsed lymphoma, clinical stage, substage, immunophenotype or treatment group. D-dimer levels >0.5 µg/mL were significantly associated with inferior median PFS (54 vs 104 days, P = .011) and OS (93 vs 169 days, P = .003). In the multivariate analysis, high D-dimer levels remained an independent predictor for worse PFS (HR: 3.21, 95% CI: 1.57-6.56, P = .001) and OS (HR: 3.87, 95% CI: 1.88-7.98; P < .001). This study suggests that pretreatment plasma D-dimer level can serve as a predictor of prognosis in dogs with intermediate to high-grade NHL. Further studies are warranted to confirm these findings.