Paclitaxel Through the Ages of Anticancer Therapy: Exploring Its Role in Chemoresistance and Radiation Therapy

Cancer Treatment Using Nanofibers: A Review

Currently, the number of patients with cancer is expanding consistently because of a low quality of life. For this reason, the therapies used to treat cancer have received a lot of consideration from specialists. Numerous anticancer medications have been utilized to treat patients with cancer. However, the immediate utilization of anticancer medicines leads to unpleasant side effects for patients and there are many restrictions to applying these treatments. A number of polymers like cellulose, chitosan, Polyvinyl Alcohol (PVA), Polyacrylonitrile (PAN), peptides and Poly (hydroxy alkanoate) have good properties for the treatment of cancer, but the nanofibers-based target and controlled drug delivery system produced by the co-axial electrospinning technique have extraordinary properties like favorable mechanical characteristics, an excellent release profile, a high surface area, and a high sponginess and are harmless, bio-renewable, biofriendly, highly degradable, and can be produced very conveniently on an industrial scale. Thus, nanofibers produced through coaxial electrospinning can be designed to target specific cancer cells or tissues. By modifying the composition and properties of the nanofibers, researchers can control the release kinetics of the therapeutic agent and enhance its accumulation at the tumor site while minimizing systemic toxicity. The core-shell structure of coaxial electrospun nanofibers allows for a controlled and sustained release of therapeutic agents over time. This controlled release profile can improve the efficacy of cancer treatment by maintaining therapeutic drug concentrations within the tumor microenvironment for an extended period.

Caspase-mediated AURKA cleavage at Asp132 is essential for paclitaxel to elicit cell apoptosis

Background: Aurora kinase A (AURKA) is a potent oncogene that is often aberrantly expressed during tumorigenesis, and is associated with chemo-resistance in various malignancies. However, the role of AURKA in chemo-resistance remains largely elusive. Methods: The cleavage of AURKA upon viral infection or apoptosis stimuli was assesed by immunoblotting assays in several cancer cells or caspase deficient cell line models. The effect of AURKA cleavage at Asp132 on mitosis was explored by live cell imaging and immunofluorescence staining experiments. The role of Asp132-cleavage of AURKA induced by the chemotherapy drug paclitaxel was investigated using TUNEL, immunohistochemistry assay in mouse tumor xenograft model and patient tissues. Results: The proteolytic cleavage of AURKA at Asp132 commonly occurs in several cancer cell types, regardless of viral infection or apoptosis stimuli. Mechanistically, caspase 3/7/8 cleave AURKA at Asp132, and the Asp132-cleaved forms of AURKA promote cell apoptosis by disrupting centrosome formation and bipolar spindle assembly in metaphase during mitosis. The AURKAD132A mutation blocks the expression of cleaved caspase 3 and EGR1, which leads to reduced therapeutic effects of paclitaxel on colony formation and malignant growth of tumor cells in vitro and in vivo using a murine xenograft model and cancer patients. Conclusions: This study reveals that caspase-mediated AURKAD132 proteolysis is essential for paclitaxel to elicit cell apoptosis and indicates that AURKAD132 is a potential key target for chemotherapy.

Epiberberine inhibits bone metastatic breast cancer-induced osteolysis

ETHNOPHARMACOLOGICAL RELEVANCE

The anti-tumor related diseases of Coptidis Rhizoma (Huanglian) were correlated with its traditional use of removing damp-heat, clearing internal fire, and counteracting toxicity. In the recent years, Coptidis Rhizoma and its components have drawn extensive attention toward their anti-tumor related diseases. Besides, Coptidis Rhizoma is traditionally used as an anti-inflammatory herb. Epiberberine (EPI) is a significant alkaloid isolated from Coptidis Rhizoma, and exhibits multiple pharmacological activities including anti-inflammatory. However, the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis has not been demonstrated clearly.

AIM OF THE STUDY

Bone metastatic breast cancer can lead to osteolysis via inflammatory factors-induced osteoclast differentiation and function. In this study, we try to analyze the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis.

METHODS

To evaluate whether epiberberine could suppress bone metastatic breast cancer-induced osteolytic damage, healthy female Balb/c mice were intratibially injected with murine triple-negative breast cancer 4T1 cells. Then, we examined the inhibitory effect and underlying mechanism of epiberberine on breast cancer-induced osteoclastogenesis in vitro. Xenograft assay was used to study the effect of epiberberine on breast cancer cells in vivo. Moreover, we also studied the inhibitory effects and underlying mechanisms of epiberberine on RANKL-induced osteoclast differentiation and function in vitro.

RESULTS

The results show that epiberberine displayed potential therapeutic effects on breast cancer-induced osteolytic damage. Besides, our results show that epiberberine inhibited breast cancer cells-induced osteoclast differentiation and function by inhibiting secreted inflammatory cytokines such as IL-8. Importantly, we found that epiberberine directly inhibited RANKL-induced differentiation and function of osteoclast without cytotoxicity. Mechanistically, epiberberine inhibited RANKL-induced osteoclastogensis via Akt/c-Fos signaling pathway. Furthermore, epiberberine combined with docetaxel effectively protected against bone loss induced by metastatic breast cancer cells.

CONCLUSIONS

Our findings suggested that epiberberine may be a promising natural compound for treating bone metastatic breast cancer-induced osteolytic damage by inhibiting IL-8 and is worthy of further exploration in preclinical and clinical trials.

Protein kinase inhibitors in the management of cancer: therapeutic opportunities from natural compounds

Kinase is an enzyme that helps in the phosphorylation of the targeted molecules and can affect their ability to react with other molecules. So, kinase influences metabolic reactions like cell signaling, secretory processes, transport of molecules, etc. The increased activity of certain kinases may cause various types of cancer, i.e. leukemia, glioblastoma, and neuroblastomas. So, the growth of particular cancer cells can be prevented by the inhibition of the kinase responsible for those cancers. Natural products are the key resources for the development of new drugs where approximately 60% of anti-tumor drugs are being developed with the same including specific kinase dwellers. This study comprised molecular interactions of various molecules (obtained from natural sources) as kinase inhibitors for the treatment of cancer. It is expected that by analyzing the skeleton behavior, the process of action, and the body-related activity of these organic products, new cancer-avoiding molecules can be developed.

Updates in pharmacotherapy for non-small cell lung cancer: a focus on emerging tubulin inhibitors

INTRODUCTION

The treatment landscape of non-small cell lung cancer (NSCLC) has seen significant advancements in recent years, marked by a shift toward target agents and immune checkpoint inhibitors (ICIs). However, chemotherapy remains a cornerstone of treatment, alone or in combination. Microtubule-targeting agents, such as taxanes and vinca alkaloids, play a crucial role in clinical practice in both early and advanced settings in NSCLC.

AREA COVERED

This review outlines the mechanisms of action, present significance, and prospective advancements of microtubule-targeting agents (MTAs), with a special highlight on new combinations in phase 3 trials. The online databases PubMed, Web of Science, Cochrane Library, and ClinicalTrials.gov were searched using the terms 'Microtubule-targeting agents' and 'non-small cell lung cancer' or synonyms, with a special focus over the last 5 years of publications.

EXPERT OPINION

Despite the emergence of immunotherapy, MTA remains crucial, often used alongside or after immunotherapy, especially in squamous cell lung cancer. Next-generation sequencing expands treatment options, but reliable biomarkers for immunotherapy are lacking. While antibody-drug conjugates (ADCs) show promise, managing toxicities remain vital. In the early stages, MTAs, possibly with ICIs, are standard, while ADCs may replace traditional chemotherapy in the advanced stages. Nevertheless, MTAs remain essential in subsequent lines or for patients with contraindications.

Deciphering the Molecular Mechanisms behind Drug Resistance in Ovarian Cancer to Unlock Efficient Treatment Options

Ovarian cancer is a highly lethal form of gynecological cancer. This disease often goes undetected until advanced stages, resulting in high morbidity and mortality rates. Unfortunately, many patients experience relapse and succumb to the disease due to the emergence of drug resistance that significantly limits the effectiveness of currently available oncological treatments. Here, we discuss the molecular mechanisms responsible for resistance to carboplatin, paclitaxel, polyadenosine diphosphate ribose polymerase inhibitors, and bevacizumab in ovarian cancer. We present a detailed analysis of the most extensively investigated resistance mechanisms, including drug inactivation, drug target alterations, enhanced drug efflux pumps, increased DNA damage repair capacity, and reduced drug absorption/accumulation. The in-depth understanding of the molecular mechanisms associated with drug resistance is crucial to unveil new biomarkers capable of predicting and monitoring the kinetics during disease progression and discovering new therapeutic targets.

Differential Sensitivity to Ionizing Radiation in Gemcitabine-Resistant and Paclitaxel-Resistant Pancreatic Cancer Cells

PURPOSE

Chemoresistance remains a major challenge in treating pancreatic ductal adenocarcinoma (PDAC). Although chemoradiation has proven effective in other tumor types, such as head and neck squamous cell carcinoma, its role in PDAC and effect on acquired chemoresistance have yet to be fully explored. In this study, we investigated the sensitivity of gemcitabine-resistant (GR) and paclitaxel-resistant (PR) PDAC cells to ionizing radiation (IR) and their underlying mechanisms.

METHODS AND MATERIALS

GR and PR clones were generated from PANC-1, PATU-T, and SUIT2-007 pancreatic cancer cell lines. Cell survival after radiation was assessed using clonogenic assay, sulforhodamine B assay, apoptosis, and spheroid growth by bioluminescence. Radiation-induced DNA damage was assessed using Western blot, extra-long polymerase chain reaction, reactive oxygen species production, and immunofluorescence. Autophagy and modulation of the Hippo signaling pathway were investigated using proteomics, Western blot, immunofluorescence, and reverse-transcription quantitative polymerase chain reaction.

RESULTS

In both 2- and 3-dimensional settings, PR cells were more sensitive to IR and showed decreased β-globin amplification, indicating more DNA damage accumulation compared with GR or wild-type cells after 24 hours. Proteomic analysis of PR PATU-T cells revealed that the protein MST4, a kinase involved in autophagy and the Hippo signaling pathway, was highly downregulated. A differential association was found between autophagy and radiation treatment depending on the cell model. Interestingly, increased yes-associated protein nuclear localization and downstream Hippo signaling pathway target gene expression were observed in response to IR.

CONCLUSIONS

This was the first study investigating the potential of IR in targeting PDAC cells with acquired chemoresistance. Our results demonstrate that PR cells exhibit enhanced sensitivity to IR due to greater accumulation of DNA damage. Additionally, depending on the specific cellular context, radiation-induced modulation of autophagy and the Hippo signaling pathway emerged as potential underlying mechanisms, findings with potential to inform personalized treatment strategies for patients with acquired chemoresistance.

Unveiling the mechanisms and challenges of cancer drug resistance

Cancer treatment faces many hurdles and resistance is one among them. Anti-cancer treatment strategies are evolving due to innate and acquired resistance capacity, governed by genetic, epigenetic, proteomic, metabolic, or microenvironmental cues that ultimately enable selected cancer cells to survive and progress under unfavorable conditions. Although the mechanism of drug resistance is being widely studied to generate new target-based drugs with better potency than existing ones. However, due to the broader flexibility in acquired drug resistance, advanced therapeutic options with better efficacy need to be explored. Combination therapy is an alternative with a better success rate though the risk of amplified side effects is commonplace. Moreover, recent groundbreaking precision immune therapy is one of the ways to overcome drug resistance and has revolutionized anticancer therapy to a greater extent with the only limitation of being individual-specific and needs further attention. This review will focus on the challenges and strategies opted by cancer cells to withstand the current therapies at the molecular level and also highlights the emerging therapeutic options -like immunological, and stem cell-based options that may prove to have better potential to challenge the existing problem of therapy resistance. Video Abstract.

Applications of synthetic yeast consortia for the production of native and non-native chemicals

The application of microbial consortia is a new approach in synthetic biology. Synthetic yeast consortia, simple or complex synthetic mixed cultures, have been used for the production of various metabolites. Cooperation between the members of a consortium and cross-feeding can be applied to create stable microbial communication. These consortia can: consume a variety of substrates, perform more complex functions, produce metabolites in high titer, rate, and yield (TRY), and show higher stability during industrial fermentations. Due to the new research context of synthetic consortia, few yeasts were used to build these consortia, including Saccharomyces cerevisiae, Pichia pastoris, and Yarrowia lipolytica. Here, application of the yeasts for design of synthetic microbial consortia and their advantages and bottlenecks for effective and robust production of valuable metabolites from bioresource, including: cellulose, xylose, glycerol and so on, have been reviewed. Key trends and challenges are also discussed for the future development of synthetic yeast consortia.

Site-specific delivery of cisplatin and paclitaxel mediated by liposomes: A promising approach in cancer chemotherapy

The site-specific delivery of drugs, especially anti-cancer drugs has been an interesting field for researchers and the reason is low accumulation of cytotoxic drugs in cancer cells. Although combination cancer therapy has been beneficial in providing cancer drug sensitivity, targeted delivery of drugs appears to be more efficient. One of the safe, biocompatible and efficient nano-scale delivery systems in anti-cancer drug delivery is liposomes. Their particle size is small and they have other properties such as adjustable physico-chemical properties, ease of functionalization and high entrapment efficiency. Cisplatin is a chemotherapy drug with clinical approval in patients, but its accumulation in cancer cells is low due to lack of targeted delivery and repeated administration results in resistance development. Gene and drug co-administration along with cisplatin/paclitaxel have resulted in increased sensitivity in tumor cells, but there is still space for more progress in cancer therapy. The delivery of cisplatin/paclitaxel by liposomes increases accumulation of drug in tumor cells and impairs activity of efflux pumps in promoting cytotoxicity. Moreover, phototherapy along with cisplatin/paclitaxel delivery can increase potential in tumor suppression. Smart nanoparticles including pH-sensitive nanoparticles provide site-specific delivery of cisplatin/paclitaxel. The functionalization of liposomes can be performed by ligands to increase targetability towards tumor cells in mediating site-specific delivery of cisplatin/paclitaxel. Finally, liposomes can mediate co-delivery of cisplatin/paclitaxel with drugs or genes in potentiating tumor suppression. Since drug resistance has caused therapy failure in cancer patients, and cisplatin/paclitaxel are among popular chemotherapy drugs, delivery of these drugs mediates targeted suppression of cancers and prevents development of drug resistance. Because of biocompatibility and safety of liposomes, they are currently used in clinical trials for treatment of cancer patients. In future, the optimal dose of using liposomes and optimal concentration of loading cisplatin/paclitaxel on liposomal nanocarriers in clinical trials should be determined.

Brain Tumors: Development, Drug Resistance, and Sensitization - An Epigenetic Approach

In this article, we describe contrasting developmental aspects of paediatric and adult brain tumours. We hypothesize that the formation of cancer progenitor cells, for both paediatric and adult, could be due to epigenetic events. However, the progression of adult brain tumours selectively involves more mutations compared to paediatric tumours. We further discuss epigenetic switches, comprising both histone modifications and DNA methylation, and how they can differentially regulate transcription and expression of oncogenes and tumour suppressor genes. Next, we summarize the currently available therapies for both types of brain tumours, explaining the merits and failures leading to drug resistance. We analyse different mechanisms of drug resistance and the role of epigenetics in this process. We then provide a rationale for combination therapy, which includes epigenetic drugs. In the end, we postulate a concept which describes how a combination therapy could be initiated. The timing, doses, and order of individual drug regimens will depend on the individual case. This type of combination therapy will be part of a personalized medicine which will differ from patient to patient.

Design, synthesis and evaluation of dihydro-1H-indene derivatives as novel tubulin polymerisation inhibitors with anti-angiogenic and antitumor potency

Angiogenesis plays an important role in tumour generation and progression, which is used to supply nutrients and metastasis. Herein, a series of novel dihydro-1H-indene derivatives were designed and evaluated as tubulin polymerisation inhibitors by binding to colchicine site, exhibiting anti-angiogenic activities against new vessel forming. Through structure-activity relationships study, compound 12d was found to be the most potent derivative possessing the antiproliferative activity against four cancer lines with IC50 values among 0.028-0.087 µM. Compound 12d bound to colchicine site on tubulin and inhibited tubulin polymerisation in vitro. In addition, compound 12d induced cell cycle arrest at G2/M phase, stimulated cell apoptosis, inhibited tumour metastasis and angiogenesis. Finally, the results of in vivo assay suggested that compound 12d could prevent tumour generation, inhibit tumour proliferation and angiogenesis without obvious toxicity. Collectively, all these findings suggested that compound 12d is a novel tubulin polymerisation inhibitor deserving further research.

Resensitizing Paclitaxel-Resistant Ovarian Cancer via Targeting Lipid Metabolism Key Enzymes CPT1A, SCD and FASN

Epithelial ovarian cancer (EOC) is a lethal gynecological cancer, of which paclitaxel resistance is the major factor limiting treatment outcomes, and identification of paclitaxel resistance-related genes is arduous. We obtained transcriptomic data from seven paclitaxel-resistant ovarian cancer cell lines and corresponding sensitive cell lines. Define genes significantly up-regulated in at least three resistant cell lines, meanwhile they did not down-regulate in the other resistant cell lines as candidate genes. Candidate genes were then ranked according to the frequencies of significant up-regulation in resistant cell lines, defining genes with the highest rankings as paclitaxel resistance-related genes (PRGs). Patients were grouped based on the median expression of PRGs. The lipid metabolism-related gene set and the oncological gene set were established and took intersections with genes co-upregulated with PRGs, obtaining 229 co-upregulated genes associated with lipid metabolism and tumorigenesis. The PPI network obtained 19 highly confidential synergistic targets (interaction score > 0.7) that directly associated with CPT1A. Finally, FASN and SCD were up-stream substrate provider and competitor of CPT1A, respectively. Western blot and qRT-PCR results confirmed the over-expression of CPT1A, SCD and FASN in the A2780/PTX cell line. The inhibition of CPT1A, SCD and FASN down-regulated cell viability and migration, pharmacological blockade of CPT1A and SCD increased apoptosis rate and paclitaxel sensitivity of A2780/PTX. In summary, our novel bioinformatic methods can overcome difficulties in drug resistance evaluation, providing promising therapeutical strategies for paclitaxel-resistant EOC via taregting lipid metabolism-related enzymes.

Inhibition of C5aR1 as a promising approach to treat taxane-induced neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of several antitumor agents resulting in progressive and often irreversible damage of peripheral nerves. In addition to their known anticancer effects, taxanes, including paclitaxel, can also induce peripheral neuropathy by activating microglia and astrocytes, which release pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin 1-beta (IL-1β), and chemokine (C-C motif) ligand 2 (CCL-2). All these events contribute to the maintenance of neuropathic or inflammatory response. Complement component 5a (C5a)/C5a receptor 1 (C5aR1) signaling was very recently shown to play a crucial role in paclitaxel-induced peripheral neuropathy. Our recent findings highlighted that taxanes have the previously unreported property of binding and activating C5aR1, and that C5aR1 inhibition by DF3966A is effective in preventing paclitaxel-induced peripheral neuropathy (PIPN) in animal models. Here, we investigated if C5aR1 inhibition maintains efficacy in reducing PIPN in a therapeutic setting. Furthermore, we characterized the role of C5aR1 activation by paclitaxel and the CIPN-associated activation of nod-like receptor (NLR) family pyrin domain containing 3 (NLRP3) inflammasome. Our results clearly show that administration of the C5aR1 inhibitor strongly reduced cold and mechanical allodynia in mice when given both during the onset of PIPN and when neuropathy is well established. C5aR1 activation by paclitaxel was found to be a key event in the induction of inflammatory factors in spinal cord, such as TNF-α, ionized calcium-binding adapter molecule 1 (Iba-1), and glial fibrillary acidic protein (GFAP). In addition, C5aR1 inhibition significantly mitigated paclitaxel-induced inflammation and inflammasome activation by reducing IL-1β and NLRP3 expression at both sciatic and dorsal root ganglia level, confirming the involvement of inflammasome in PIPN. Moreover, paclitaxel-induced upregulation of C5aR1 was significantly reduced by DF3966A treatment in central nervous system. Lastly, the antinociceptive effect of C5aR1 inhibition was confirmed in an in vitro model of sensory neurons in which we focused on receptor channels usually activated upon neuropathy. In conclusion, C5aR1 inhibition is proposed as a therapeutic option with the potential to exert long-term protective effect on PIPN-associated neuropathic pain and inflammation.

Potential Association of Cytochrome P450 Copy Number Alteration in Tumour with Chemotherapy Resistance in Lung Adenocarcinoma Patients

Resistance to anticancer agents is a major obstacle to efficacious tumour therapy and responsible for high cancer-related mortality rates. Some resistance mechanisms are associated with pharmacokinetic variability in anticancer drug exposure due to genetic polymorphisms of drug-metabolizing cytochrome P450 (CYP) enzymes, whereas variations in tumoural metabolism as a consequence of CYP copy number alterations are assumed to contribute to the selection of resistant cells. A high-throughput quantitative polymerase chain reaction (qPCR)-based method was developed for detection of CYP copy number alterations in tumours, and a scoring system improved the identification of inappropriate reference genes that underwent deletion/multiplication in tumours. The copy numbers of both the target (CYP2C8, CYP3A4) and the reference genes (ALB, B2M, BCKDHA, F5, CD36, MPO, TBP, RPPH1) established in primary lung adenocarcinoma by the qPCR-based method were congruent with those determined by next-generation sequencing (for 10 genes, slope = 0.9498, r2 = 0.72). In treatment naïve adenocarcinoma samples, the copy number multiplication of paclitaxel-metabolizing CYP2C8 and/or CYP3A4 was more prevalent in non-responder patients with progressive disease/exit than in responders with complete remission. The high-throughput qPCR-based method can become an alternative approach to next-generation sequencing in routine clinical practice, and identification of altered CYP copy numbers may provide a promising biomarker for therapy-resistant tumours.

Exosome-Based Drug Delivery: Translation from Bench to Clinic

Exosome-based drug delivery is emerging as a promising field with the potential to revolutionize therapeutic interventions. Exosomes, which are small extracellular vesicles released by various cell types, have attracted significant attention due to their unique properties and natural ability to transport bioactive molecules. These nano-sized vesicles, ranging in size from 30 to 150 nm, can effectively transport a variety of cargoes, including proteins, nucleic acids, and lipids. Compared to traditional drug delivery systems, exosomes exhibit unique biocompatibility, low immunogenicity, and reduced toxicity. In addition, exosomes can be designed and tailored to improve targeting efficiency, cargo loading capacity, and stability, paving the way for personalized medicine and precision therapy. However, despite the promising potential of exosome-based drug delivery, its clinical application remains challenging due to limitations in exosome isolation and purification, low loading efficiency of therapeutic cargoes, insufficient targeted delivery, and rapid elimination in circulation. This comprehensive review focuses on the transition of exosome-based drug delivery from the bench to clinic, highlighting key aspects, such as exosome structure and biogenesis, cargo loading methods, surface engineering techniques, and clinical applications. It also discusses challenges and prospects in this emerging field.

Physiological and metabolic traits of Taxol biosynthesis of endophytic fungi inhabiting plants: Plant-microbial crosstalk, and epigenetic regulators

Attenuating the Taxol productivity of fungi with the subculturing and storage under axenic conditions is the challenge that halts the feasibility of fungi to be an industrial platform for Taxol production. This successive weakening of Taxol productivity by fungi could be attributed to the epigenetic down-regulation and molecular silencing of most of the gene clusters encoding Taxol biosynthetic enzymes. Thus, exploring the epigenetic regulating mechanisms controlling the molecular machinery of Taxol biosynthesis could be an alternative prospective technology to conquer the lower accessibility of Taxol by the potent fungi. The current review focuses on discussing the different molecular approaches, epigenetic regulators, transcriptional factors, metabolic manipulators, microbial communications and microbial cross-talking approaches on restoring and enhancing the Taxol biosynthetic potency of fungi to be industrial platform for Taxol production.

Revisiting the Flora of Saudi Arabia: Phytochemical and Biological Investigation of the Endangered Plant Species Euphorbia saudiarabica

Euphorbia plants have a significant place in traditional medicine due to their numerous therapeutic properties, including their anti-tumor effects, which have been observed in several species. In the current study, a phytochemical investigation of Euphorbia saudiarabica methanolic extract led to the isolation and characterization of four secondary metabolites from the chloroform (CHCl₃) and ethyl acetate (EtOAc) fractions, which are reported for the first time in this species. One of the constituents, saudiarabicain F (2), is a rare C-19 oxidized ingol-type diterpenoid that has not been previously reported. The structures of these compounds were determined by extensive spectroscopic (HR-ESI-MS, 1D and 2D NMR) analyses. The anticancer properties of the E. saudiarabica crude extract, its fractions and its isolated compounds were examined against several cancer cells. The active fractions were evaluated for their effects on cell-cycle progression and apoptosis induction using flow cytometry. Furthermore, RT-PCR was employed to estimate the gene-expression levels of the apoptosis-related genes. It was demonstrated that the E. saudiarabica CHCl₃ and EtOAc fractions suppressed the proliferation of the cancer cells. The MCF-7 cells were the most sensitive to both fractions, with IC₅₀ values of 22.6 and 23.2 µg/mL, respectively. Notably, both fractions caused cell-cycle arrest in the G2/M phase of the treated MCF-7 cells. The inhibition of the MCF-7 cells' proliferation was also linked with apoptosis induction by flow-cytometry analysis. Additionally, the activation of apoptosis by both fractions was demonstrated by an increase in the ratio of Bax to Bcl-2, with an increase in the expression of caspase-7. Among the isolated compounds, glutinol (1) showed potent activity against the MCF-7 cell line, with an IC₅₀ value of 9.83 µg/mL. Our findings suggest that E. saudiarabica has apoptosis-inducing effects and shows promise as a potential source of new chemotherapeutic drugs.

Radiotherapy opens the blood-brain barrier and synergizes with anlotinib in treating glioblastoma

BACKGROUND

Glioblastoma (GBM) has a poor prognosis and lacks effective treatment. Anlotinib is a multitargeted receptor tyrosine kinase inhibitor (TKI) that may have anti-tumor activity in the central nervous system (CNS). This study aimed to determine the therapeutic value of radiotherapy combined with anlotinib in GBM via preclinical research.

METHODS

HPLC-MS/MS was used to assess the concentration of anlotinib in blood and brain samples. Cell proliferation assays, flow cytometry, and colony formation assays were performed in vitro. The potential value of anlotinib or in combination with radiotherapy for GBM treatment was estimated in vivo. Western blotting, immunohistochemistry, and immunofluorescent staining were performed to determine the underlying mechanism.

RESULTS

Anlotinib effectively inactivated the JAK3/STAT3 pathway to inhibit growth and induce apoptosis in malignant glioma cells (MGCs) independent of MGMT expression. Meanwhile, anlotinib induces MGCs G2/M arrest and sensitizes MGCs to radiation. Radiation down-regulates claudin-5 and weakens the blood-brain barrier (BBB), which contributes to the increased distribution of anlotinib in the CNS by 1.0-2.9 times. Anlotinib restrains tumor growth (PCNA), inhibits tumor microvascular proliferation (CD31), and alleviated intratumor hypoxia (HIF 1α) in vivo. Anlotinib alone or in combination with radiation is effective and safe in vivo evaluation.

CONCLUSIONS

We discovered that anlotinib, the original small molecule antiangiogenesis TKI, down-regulates JAK3/STAT3 axis with anti-cancer activity alone or in combination with radiation. Anlotinib combined with radiotherapy might be a promising treatment for newly diagnosed GBM in the clinic.

Evaluation of the parameters affecting the loading of anticancer drug Paclitaxel on coated gold nanoparticles for breast cancer treatment

The purpose of this study is the design and synthesis of gold nanoparticles (GNPs) conjugated with paclitaxel and to investigate the parameters affecting the stability of synthesised nanoparticles with drug delivery capability. Here, synthesised GNPs were coated with polyethylene glycol. Then these particles were conjugated with paclitaxel under different conditions and the physical and structural characteristics, as well as the factors affecting the loading of paclitaxel on nanoparticles, were evaluated by ultraviolet spectrophotometer, fourier transform infrared spectroscopy, transmission electron microscopy, dynamic light scattering and zeta potential apparatus. It was found that pegylated GNPs have a limited loading capacity at the time of 24 h of incubation and the Paclitaxel loading was observed to be pH dependent. The use of these particles in the treatment of breast cancer (MCF7) was also investigated using the MTT test. It was determined that the survival percentage of MCF7 cells in the presence of paclitaxel-bound nanoparticles decreases to about 55% at the maximum measured concentration (690 μM).

Transporter-mediated Natural Product-Drug Interactions

The increasing use of natural products in clinical practice has raised great concerns about the potential natural product-drug interactions (NDIs). Drug transporters mediate the transmembrane passage of a broad range of drugs, and thus are important determinants for drug pharmacokinetics and pharmacodynamics. Generally, transporters can be divided into ATP binding cassette (ABC) family and solute carrier (SLC) family. Numerous natural products have been identified as inhibitors, substrates, inducers, and/or activators of drug transporters. This review article aims to provide a comprehensive summary of the recent progress on the research of NDIs, focusing on the main drug transporters, such as P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), organic anion transporter 1 and 3 (OAT1/OAT3), organic anion-transporting polypeptide 1B1 and 1B3 (OATP1B1/OATP1B3), organic cation transporter 2 (OCT2), multidrug and toxin extrusion protein 1 and 2-K (MATE1/MATE2-K). Additionally, the challenges and strategies of studying NDIs are also discussed.

The role of cur ole of curcumin against paclitax cumin against paclitaxel-induced o el-induced oxidativ xidative stress and DNA damage in testes of adult male rats

BACKGROUND

Paclitaxel is a widely used drug for the treatment of cancer, but it possesses toxic effects on male reproductive system. Administering paclitaxel with an antioxidant has become a strategy for preventing the side effects of paclitaxel. Although curcumin is an antioxidant, data concerning the effect of curcumin on paclitaxel-induced testis tissue are lacking. The present study was established to examine the protective impact of curcumin against testicular damage induced by paclitaxel.

METHODS

In the study, 40 Wistar albino male rats were used and randomly divided into 4 groups (n:10). The control group received only saline solution; the curcumin group received curcumin throughout the experiment; the paclitaxel group received a total of four doses of paclitaxel on days 1, 7, 14, and 21 of the experiment; curcumin + paclitaxel group received curcumin throughout the experiment and a total of four doses of paclitaxel on days 1, 7, 14, and 21 of the experiment. At the end of the experiment, the rats were decapitated under xylazine and ketamine anesthesia and their testicles were removed. The sections obtained from the testicles were stained with Hematoxylin & Eosin and histopathological damage was evaluated. The TUNEL method was applied to determine apoptotic cells. Testosterone levels were measured in the blood serum. The Johnsen testicular biopsy score (JTBS) was used to evaluate testicular tubules. DNA damage was evaluated in sperm samples taken from the ductus epididymis using the comet assay technique.

RESULTS

Testicular tissue was severely damaged in the paclitaxel group. In the curcumin + paclitaxel group, it was determined that the administration of curcumin with paclitaxel reduced the histological damage in the testicular tissue. Moreover, according to the JTBS, the value was significantly higher in the testicular tubules (p < 0.05). Testosterone levels were higher in curcumin + paclitaxel group than in paclitaxel group. DNA damage also decreased significantly in curcumin + paclitaxel group when compared to paclitaxel group (p < 0.05).

DISCUSSION

The results showed that curcumin may be protective against damage caused by paclitaxel in the testicles of rats.

Chloroquine Sensitizes Esophageal Carcinoma EC109 Cells to Paclitaxel by Inhibiting Autophagy

As an autophagy inhibitor, chloroquine (CQ) showed anti-tumor effect on several types of cancer and paclitaxel (PTX) is widely used in the treatment of esophageal carcinoma patients, but chemoresistance remains a major hurdle for PTX application due to the cytoprotective autophagy. Therefore, the aim of this study was to investigate whether CQ could elevate the anti-tumor effect of PTX on esophageal carcinoma cell line EC109 and explore the potential molecular mechanisms. We confirmed the suppressive effect of PTX on EC109 by MTT, scratch test, transwell and soft agar assay. And, we detected the key proteins in Akt/mTOR pathway, as well as the autophagy marker LC3 and p62 through Western Blot. In addition, GFP-LC3 plasmid was transfected into EC109 cells to monitor the autophagosome after CQ and PTX treatment. Ultimately, we observed the alterations in the proliferation and colony formation abilities of EC109 after knocking down mTOR by shRNA. We confirmed PTX could suppress the proliferation, migration and colony formation (all P < 0.05) abilities of EC109, and CQ could sensitize the inhibition effect of PTX by inhibiting autophagy through Akt/mTOR pathway. Furthermore, inhibiting Akt/mTOR pathway initiated autophagy and enhanced the sensitivity of EC109 to CQ and PTX. In summary, we suggest CQ could be used as a potential chemosensitizer for PTX in esophageal carcinoma treatment.

Evaluation of cytotoxicity, loading, and release activity of paclitaxel loaded-porphyrin based metal-organic framework (PCN-600)

Considering the inducement side impacts and precipitation of continual doses in conventional therapeutic treatments, there is an urgent need in the field of drug delivery for novel designs of biocompatible carriers with wide loading dimensions and particularly the ability to control their drug release. In this work, we succeeded in synthesizing an iron-based organic metal framework based on iron-porphyrin (PCN-600) through a solvothermal method to function as a drug delivery system (DDS). According to SEM results, PCN-600 crystals a hexagonal-rod shaped morphology with the length of 300 nm and width of 100-300 nm. As an anticancer drug, Paclitaxel (PTX) was successfully loaded into the porphyrin-based metal-organic framework (PCN-600) via in-situ encapsulation; the loading efficiency was measured to be about 87.3%. In addition, PTX-encapsulated PCN-600 displayed a controlled and sustained release for up to 24 h of release assessment at the physiological microenvironment of pH = 7.4.

Palmitoylethanolamide Mitigates Paclitaxel Toxicity in Primary Dorsal Root Ganglion Neurons

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of several chemotherapeutic agents, such as Paclitaxel. The main symptoms of CIPN are pain and numbness in the hands and feet. Paclitaxel is believed to accumulate in the dorsal root ganglia and free nerve endings. Novel therapeutic agents might help to mitigate or prevent Paclitaxel toxicity on dorsal root ganglion (DRG) neurons. Thus, we used primary DRG neurons as a model to investigate the potential neuroprotective effects of the endocannabinoid-like substance, palmitoylethanolamide (PEA). DRG neurons were isolated from cervical to sacral segments of spinal nerves of Wister rats (6-8 weeks old). After isolation and purification of neuronal cell populations, different concentrations of Paclitaxel (0.01-10 µM) or PEA (0.1-10 µM) or their combination were tested on cell viability by MTT assay at 24 h, 48, and 72 h post-treatment. Furthermore, morphometric analyses of neurite length and soma size for DRG neurons were performed. Adverse Paclitaxel effects on cell viability were apparent at 72 h post-treatment whereas Paclitaxel significantly reduced the neurite length in a concentration-dependent manner nearly at all investigated time points. However, Paclitaxel significantly increased the size of neuronal cell bodies at all time windows. These phenotypic effects were significantly reduced in neurons additionally treated with PEA, indicating the neuroprotective effect of PEA. PEA alone led to a significant increase in neuron viability regardless of PEA concentrations, apparent improvements in neurite outgrowth as well as a significant decrease in soma size of neurons at different investigated time points. Taken together, PEA showed promising protective effects against Paclitaxel-related toxicity on DRG neurons.

Neurophysiopathological Aspects of Paclitaxel-induced Peripheral Neuropathy

Chemotherapy is widely used as a primary treatment or adjuvant therapy for cancer. Anti-microtubule agents (such as paclitaxel and docetaxel) are used for treating many types of cancer, either alone or in combination. However, their use has negative consequences that restrict the treatment's ability to continue. The principal negative effect is the so-called chemotherapy-induced peripheral neuropathy (CIPN). CIPN is a complex ailment that depends on diversity in the mechanisms of action of the different chemotherapy drugs, which are not fully understood. In this paper, we review several neurophysiological and pathological characteristics, such as morphological changes, changes in ion channels, mitochondria and oxidative stress, cell death, changes in the immune response, and synaptic control, as well as the characteristics of neuropathic pain produced by paclitaxel.

A small molecule inhibitor of the UBE2F-CRL5 axis induces apoptosis and radiosensitization in lung cancer

Protein neddylation is catalyzed by a neddylation activating enzyme (NAE, E1), an E2 conjugating enzyme, and an E3 ligase. In various types of human cancers, the neddylation pathway is abnormally activated. Our previous study validated that the neddylation E2 UBE2F is a promising therapeutic target in lung cancer. Although the NAE inhibitor MLN4924/pevonedistat is currently under clinical investigation as an anti-cancer agent, there are no small molecules available that selectively target UBE2F. Here, we report, for the first time, the discovery, via structure-based virtual screen and chemical optimization, of such a small molecule, designated as HA-9104. HA-9104 binds to UBE2F, reduces its protein levels, and consequently inhibits cullin-5 neddylation. Blockage of cullin-5 neddylation inactivates cullin-RING ligase-5 (CRL5) activity, leading to accumulation of the CRL5 substrate, NOXA, to induce apoptosis. Moreover, HA-9104 appears to form the DNA adduct via its 7-azaindole group to induce DNA damage and G2/M arrest. Biologically, HA-9104 effectively suppresses the growth and survival of lung cancer cells and confers radiosensitization in both in vitro cell culture and in vivo xenograft tumor models. In summary, we discovered a small molecule, designated HA-9104, that targets the UBE2F-CRL5 axis with anti-cancer activity alone or in combination with radiation.

Brachytherapy via a depot of biopolymer-bound 131I synergizes with nanoparticle paclitaxel in therapy-resistant pancreatic tumours

Locally advanced pancreatic tumours are highly resistant to conventional radiochemotherapy. Here we show that such resistance can be surmounted by an injectable depot of thermally responsive elastin-like polypeptide (ELP) conjugated with iodine-131 radionuclides (131I-ELP) when combined with systemically delivered nanoparticle albumin-bound paclitaxel. This combination therapy induced complete tumour regressions in diverse subcutaneous and orthotopic mouse models of locoregional pancreatic tumours. 131I-ELP brachytherapy was effective independently of the paclitaxel formulation and dose, but external beam radiotherapy (EBRT) only achieved tumour-growth inhibition when co-administered with nanoparticle paclitaxel. Histological analyses revealed that 131I-ELP brachytherapy led to changes in the expression of intercellular collagen and junctional proteins within the tumour microenvironment. These changes, which differed from those of EBRT-treated tumours, correlated with the improved delivery and accumulation of paclitaxel nanoparticles within the tumour. Our findings support the further translational development of 131I-ELP depots for the synergistic treatment of localized pancreatic cancer.

Rationale for combination of paclitaxel and CDK4/6 inhibitor in ovarian cancer therapy — non-mitotic mechanisms of paclitaxel

Taxanes and CDK4/6 inhibitors (CDK4/6i) are two families of successful anti-mitotic drugs used in the treatment of solid tumors. Paclitaxel, representing taxane compounds, has been used either alone or in combination with other agents (commonly carboplatin/cisplatin) in the treatment of many solid tumors including ovarian, breast, lung, prostate cancers, and Kaposi’s sarcoma. Paclitaxel has been routinely prescribed in cancer treatment since the 1990s, and its prominent role is unlikely to be replaced in the foreseeable future. Paclitaxel and other taxanes work by binding to and stabilizing microtubules, causing mitotic arrest, aberrant mitosis, and cell death. CDK4/6i (palbociclib, ribociclib, abemaciclib) are relatively new cell cycle inhibitors that have been found to be effective in breast cancer treatment, and are currently being developed in other solid tumors. CDK4/6i blocks cell cycle progression at the G1 phase, resulting in cell death by mechanisms not yet fully elucidated. At first glance, paclitaxel and CDK4/6i are unlikely synergistic agents as both are cell cycle inhibitors that work at different phases of the cell cycle, and few clinical trials have yet considered adding CDK4/6i to existing paclitaxel chemotherapy. However, recent findings suggest the importance of a non-mitotic mechanism of paclitaxel in cancer cell death and pre-clinical data support rationale for a strategic paclitaxel and CDK4/6i combination. In mouse tumor model studies, drug sequencing resulted in differential efficacy, indicating complex biological interactions of the two drugs. This article reviews the rationales of combining paclitaxel with CDK4/6i as a potential therapeutic option in recurrent ovarian cancer.

Based on different immune responses under the glucose metabolizing type of papillary thyroid cancer and the response to anti-PD-1 therapy

Glucose metabolism-related genes play an important role in the development and immunotherapy of many tumours, but their role in thyroid cancer is ambiguous. To investigate the role of glucose metabolism-related genes in the development of papillary thyroid cancer (PTC) and their correlation with the clinical outcome of PTC, we collected transcriptomic data from 501 PTC patients in the Cancer Genome Atlas (TCGA). We performed nonnegative matrix decomposition clustering of 2752 glucose metabolism-related genes from transcriptome data and classified PTC patients into three subgroups (C1 for high activation of glucose metabolism, C2 for low activation of glucose metabolism and C3 for moderate activation of glucose metabolism) based on the activation of different glucose metabolism-related genes in 10 glucose metabolism-related pathways. We found a positive correlation between the activation level of glucose metabolism and the tumour mutation burden (TMB), neoantigen number, mRNA stemness index (mRNAsi), age, and tumour stage in PTC patients. Next, we constructed a prognostic prediction model for PTC using six glucose metabolism-related genes (PGBD5, TPO, IGFBPL1, TMEM171, SOD3, TDRD9) and constructed a nomogram based on the risk score and clinical parameters of PTC patients. Both the prognostic risk prediction model and nomogram had high stability and accuracy for predicting the progression-free interval (PFI) in PTC patients. Patients were then divided into high-risk and low-risk groups by risk score. The high-risk group was sensitive to paclitaxel and anti-PD-1 treatment, and the low-risk group was sensitive to sorafenib treatment. We found that the high-risk group was enriched in inflammatory response pathways and associated with high level of immune cell infiltration. To verify the accuracy of the prognostic prediction model, we knocked down PGBD5 in PTC cells and found that the proliferation ability of PTC cells was significantly reduced. This suggests that PGBD5 may be a relatively important oncogene in PTC. Our study constructed a prognostic prediction model and classification of PTC by glucose metabolism-related genes, which provides a new perspective on the role of glucose metabolism in the development and immune microenvironment of PTC and in guiding chemotherapy, targeted therapy and immune checkpoint blockade therapy of PTC.

Microbial sophorolipids inhibit colorectal tumour cell growth in vitro and restore haematocrit in Apcmin+/- mice

Abstract

Sophorolipids are glycolipid biosurfactants consisting of a carbohydrate sophorose head with a fatty acid tail and exist in either an acidic or lactonic form. Sophorolipids are gaining interest as potential cancer chemotherapeutics due to their inhibitory effects on a range of tumour cell lines. Currently, most anti-cancer studies reporting the effects of sophorolipids have focused on lactonic preparations with the effects of acidic sophorolipids yet to be elucidated. We produced a 94% pure acidic sophorolipid preparation which proved to be non-toxic to normal human colonic and lung cells. In contrast, we observed a dose-dependent reduction in viability of colorectal cancer lines treated with the same preparation. Acidic sophorolipids induced apoptosis and necrosis, reduced migration, and inhibited colony formation in all cancer cell lines tested. Furthermore, oral administration of 50 mg kg⁻¹ acidic sophorolipids over 70 days to Apc^min+/− mice was well tolerated and resulted in an increased haematocrit, as well as reducing splenic size and red pulp area. Oral feeding did not affect tumour numbers or sizes in this model. This is the first study to show that acidic sophorolipids dose-dependently and specifically reduces colon cancer cell viability in addition to reducing tumour-associated bleeding in the Apc^min+/− mouse model.

Key points

• Acidic sophorolipids are produced by yeast species such as Starmerella bombicola.

• Acidic sophorolipids selectively killed colorectal cells with no effect on healthy gut epithelia.

• Acidic sophorolipids reduced tumour-associated gut bleed in a colorectal mouse model.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00253-022-12115-6.

Anti-Proliferative Potential of Quercetin Loaded Polymeric Mixed Micelles on Rat C6 and Human U87MG Glioma Cells

Quercetin (Qu) is a natural flavonoid present in many commonly consumed food items and is also identified as a potential anticancer agent. The present study evaluates the Qu-loaded polymeric mixed micelles (Qu-PMMs) against C6 and U87MG glioma cell lines. The Box–Behnken Design (BBD) was employed to study the influence of independent variables such as Soluplus, Vitamin-E polyethyleneglycol-1000 succinate (E-TPGS), and poloxamer 407 concentrations on dependent variables including particle size (PS), polydispersity index (PDI), and percentage entrapment efficiency (%EE) of the prepared Qu-PMMs. The Qu-PMMs were further characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and were assessed for in vitro drug release, effect on cell viability, migration, cellular uptake, and apoptosis assays. The PS, PDI, and % EE of the optimized PMMs were 107.16 ± 1.06 nm, 0.236 ± 0.053, and 77.46 ± 1.94%, respectively. The FTIR and XRD revealed that the Qu was completely entrapped inside the PMMs. The SEM analysis confirmed the spherical shape of micelles. The in vitro cell viability study showed that the Qu-PMMs had 1.7 times higher cytotoxicity against C6 and U87MG cells than Qu pure drug (Qu-PD). Furthermore, Qu-PMMs demonstrated superior cellular uptake, inhibited migration, and induced apoptosis when tested against C6 and U87MG cells than pure Qu. Thus, the polymeric mixed micelle (PMMs) enhanced the therapeutic effect of Qu and can be considered an effective therapeutic strategy to treat Glioma.

Stabilization of F-Actin Cytoskeleton by Paclitaxel Improves the Blastocyst Developmental Competence through P38 MAPK Activity in Porcine Embryos

Changes in F-actin distribution and cortical F-actin morphology are important for blastocyst developmental competence during embryogenesis. However, the effect of paclitaxel as a microtubule stabilizer on embryonic development in pigs remains unclear. We investigated the role of F-actin cytoskeleton stabilization via P38 MAPK activation using paclitaxel to improve the developmental potential of blastocysts in pigs. In this study, F-actin enrichment and adducin expression based on blastomere fragment rate and cytokinesis defects were investigated in cleaved embryos after in vitro fertilization (IVF). Adducin and adhesive junction F-actin fluorescence intensity were significantly reduced with increasing blastomere fragment rate in porcine embryos. In addition, porcine embryos were cultured with 10 and 100 nM paclitaxel for two days after IVF. Adhesive junction F-actin stabilization and p-P38 MAPK activity in embryos exposed to 10 nM paclitaxel increased significantly with blastocyst development competence. However, increased F-actin aggregation, cytokinesis defects, and over-expression of p-P38 MAPK protein by 100 nM paclitaxel exposure disrupted blastocyst development in porcine embryos. In addition, exposure to 100 nM paclitaxel increased the misaligned α-tubulin of spindle assembly and adhesive junction F-actin aggregation at the blastocyst stage, which might be caused by p-P38 protein over-expression-derived apoptosis in porcine embryos.

Paclitaxel and Urolithin A Prevent Histamine-Induced Neurovascular Breakdown Alike, in an Ex Vivo Rat Eye Model

Neurovascular eye problems are better prevented than managed or treated. Despite growing concern of occurrence in aging populations and development secondary to diseases such as diabetes and hypertension, we currently have very few options to tackle this global problem. Creating effective and high-throughput screening strategies is as important as the intervention itself. Here, we present for the first time a robust ex vivo rat eye model of histamine-induced vascular damage for investigating the therapeutic potential of paclitaxel (PTX) and urolithin A (UA) as alternatives to dexamethasone for preventing vascular damage in the retina. Extensive loss of vascularization and apoptosis were observed in the histamine-challenged group and successfully prevented in the intervention groups, more significantly in the PTX and UA. These important early results indicate that PTX and UA could be developed as potential preventive strategies for a wide variety of retinal diseases.

Paclitaxel binds and activates C5aR1: A new potential therapeutic target for the prevention of chemotherapy-induced peripheral neuropathy and hypersensitivity reactions

Chemotherapy-induced peripheral neuropathy (CIPN) and hypersensitivity reactions (HSRs) are among the most frequent and impairing side effects of the antineoplastic agent paclitaxel. Here, we demonstrated that paclitaxel can bind and activate complement component 5a receptor 1 (C5aR1) and that this binding is crucial in the etiology of paclitaxel-induced CIPN and anaphylaxis. Starting from our previous data demonstrating the role of interleukin (IL)-8 in paclitaxel-induced neuronal toxicity, we searched for proteins that activate IL-8 expression and, by using the Exscalate platform for molecular docking simulations, we predicted the high affinity of C5aR1 with paclitaxel. By in vitro studies, we confirmed the specific and competitive nature of the C5aR1-paclitaxel binding and found that it triggers intracellularly the NFkB/P38 pathway and c-Fos. In F11 neuronal cells and rat dorsal root ganglia, C5aR1 inhibition protected from paclitaxel-induced neuropathological effects, while in paclitaxel-treated mice, the absence (knock-out mice) or the inhibition of C5aR1 significantly ameliorated CIPN symptoms-in terms of cold and mechanical allodynia-and reduced the chronic pathological state in the paw. Finally, we found that C5aR1 inhibition can counteract paclitaxel-induced anaphylactic cytokine release in macrophages in vitro, as well as the onset of HSRs in mice. Altogether these data identified C5aR1 as a key mediator and a new potential pharmacological target for the prevention and treatment of CIPN and HSRs induced by paclitaxel.

nurP28, a New-to-Nature Zein-Derived Peptide, Enhances the Therapeutic Effect of Docetaxel in Breast Cancer Monolayers and Spheroids

The development of novel cancer therapeutic strategies has garnered increasing interest in cancer research. Among the therapeutic choices, chemosensitizers have shown exciting prospects. Peptides are an attractive alternative among the molecules that may be used as chemosensitizers. We rationally designed a new-to-nature peptide, nurP28, derived from the 22-kDa α-zein protein sequence (entry Q00919_MAIZE). The resultant sequence of the nurP28 peptide after the addition of arginine residues was LALLALLRLRRRATTAFIIP, and we added acetyl and amide groups at the N- and C-terminus, respectively, for capping. We evaluated the cytotoxicity of the nurP28 peptide alone and in combination with docetaxel in fibroblast monolayers and breast cancer monolayers and spheroids. Our results indicated that nurP28 is not cytotoxic to human fibroblasts or cancer cells. Nevertheless, when combined with 1 µM docetaxel, 3 ng/mL nurP28 induced equivalent (in MCF7 monolayers) and higher (in MCF7 spheroids) cytotoxic effects than 10-fold higher doses of docetaxel alone. These findings suggest that nurP28 may act as a chemosensitizer in breast cancer treatment. This study describes the enhancing “anti-cancer” effects of nurP28 in breast cancer 2D and 3D cultures treated with docetaxel. Further studies should explore the mechanisms underlying these effects and assess the clinical potential of our findings using animal models.

Anticancer Efficacy of 6-Gingerol with Paclitaxel against Wild Type of Human Breast Adenocarcinoma

Breast cancer is one of the most common malignant neoplasms, and despite the dynamic development of anticancer therapies, 5-year survival in the metastatic stage is still less than 30%. 6-Gingerol (1-[4′-hydroxy-3′-methoxyphenyl]-5-hydroxy-3-decanone) is a substance contained in ginger, which exhibits anti-cancer properties. Paclitaxel is a cytostatic substance used to treat breast cancer, but its therapeutically effective dose has many adverse effects. The aim of the presented study was to assess the anticancer effect of 6-gingerol and the possibility of increasing the effectiveness of Paclitaxel in the death induction of wild type human breast cancer cells. MCF-7/WT cells were treated with drugs—6-gingerol and paclitaxel at selected concentrations. The mitochondrial activity assay, caspase 7 activity assay, ATP assay, microscopy studies, and RT-PCR assays were performed to evaluate the antitumor activity and mechanism of action of both compounds, alone and in combination. After 72 h of incubation, the mitochondrial activity showed that the combination of 5 nM Paclitaxel with 10 µM 6-Gingerol led to the same decrease in viability as the use of 20 nM Paclitaxel alone; 10 µM 6-Gingerol led to an enhancement of caspase 7 activity, with the highest activity observed after 24 h of incubation. A real-time PCR study showed that 6-Gingerol induces the simultaneous transcription of Bax with TP53 genes in large excess to BCL-2. In contrast, 5 nM Paclitaxel induces TP53 transcription in excess of BCL-2 and Bax. Our results suggest that 6-Gingerol may act as a cell death-inducing agent in cancer cells and, in combination with paclitaxel, and increase the effectiveness of conventional chemotherapy.

Evaluation of PEG-b-polycarbonates self-assemblies containing azobenzene or coumarin moieties as nanocarriers using paclitaxel as a model hydrophobic drug

AIM

The work assesses the performance of nanocarriers from amphiphilic block copolymers with functional azobenzene or coumarin moieties for delivery of paclitaxel.

METHODS

Placlitaxel was encapsulated by the nanoprecipitation method. Characterizations were performed by DLS, TEM, Zeta potential and HPLC. Cell viability was investigated in HeLa and Huh-5-2-cell lines.

RESULTS

Coumarin-containing polymeric micelles (D_h = 26 ± 2 nm, PDI =0.28, ζ = ‒22.9 ± 3.6 mV) with 11.2 ± 0.5%w/w drug loading showed enhanced cytotoxicity in HeLa cells (IC50 < 0.02 nM) compared to free paclitaxel (IC50 = 0.17 ± 0.02 nM). Azobenzene-containing polymeric vesicles (D_h = 390 ± 20 nm, PDI =0.24, ζ = ‒33.2 ± 5.0 mV) with a 6.8 ± 0.4%w/w drug loading showed increased cytotoxicity under 530 nm light (IC50 = 0.0114 ± 0.00033 nM) in HeLa cells due to a stimulated delivery of paclitaxel.

CONCLUSION

Effectivity of these block copolymers as paclitaxel nanovectors and light stimulated release has been demonstrated.

Tissue Type Differences in ABCB1 Expression and Paclitaxel Tissue Pharmacokinetics in Patients With Esophageal Cancer

Background: Data from previous work suggests that there is no correlation between systemic (plasma) paclitaxel exposure and efficacy in patients treated for esophageal cancer. In this trial, we investigated ATP-binding cassette efflux transporter expression and intratumoral pharmacokinetics of paclitaxel to identify changes which could be a first sign of chemoresistance.

Methods: Patients with esophageal cancer treated with paclitaxel and carboplatin (± concomitant radiotherapy) were included. During the first and last cycle of weekly paclitaxel, blood samples and biopsies of esophageal mucosa and tumor tissue were taken. Changes in paclitaxel exposure and expression of ABCB1 (P-glycoprotein) over time were studied in both tumor tissue and normal appearing esophageal mucosa.

Results: ABCB1 was significantly higher expressed in tumor tissue compared to esophageal tissue, during both the first and last cycle of paclitaxel (cycle 1: p < 0.01; cycle 5/6: p = 0.01). Interestingly, ABCB1 expression was significantly higher in adenocarcinoma than in squamous cell carcinoma (p < 0.01). During the first cycle, a trend towards a higher intratumoral paclitaxel concentration was observed compared to the esophageal mucosa concentration (RD:43%; 95%CI: −3% to 111% p = 0.07). Intratumoral and plasma paclitaxel concentrations were significantly correlated during the first cycle (AUC_0–48 h: r = 0.72; p < 0.01).

Conclusion: Higher ABCB1 expression in tumor tissue, and differences between histological tumor types might partly explain why tumors respond differently to systemic treatment. Resistance by altered intratumoral paclitaxel concentrations could not be demonstrated because the majority of the biopsies taken at the last cycle of paclitaxel did contain a low amount of tumor cells or no tumor.

STMN1 is highly expressed and contributes to clonogenicity in acute promyelocytic leukemia cells

Stathmin 1 (STMN1) is a microtubule-destabilizing protein highly expressed in hematological malignancies and involved in proliferation and differentiation. Although a previous study found that the PML-RARα fusion protein, which contributes to the pathophysiology of acute promyelocytic leukemia (APL), positively regulates STMN1 at the transcription and protein activity levels, little is known about the role of STMN1 in APL. In this study, we aimed to investigate the STMN1 expression levels and their associations with laboratory, clinical, and genomic data in APL patients. We also assessed the dynamics of STMN1 expression during myeloid cell differentiation and cell cycle progression, and the cellular effects of STMN1 silencing and pharmacological effects of microtubule-stabilizing drugs on APL cells. We found that STMN1 transcripts were significantly increased in samples from APL patients compared with those of healthy donors (all p < 0.05). However, this had no effect on clinical outcomes. STMN1 expression was associated with proliferation- and metabolism-related gene signatures in APL. Our data confirmed that STMN1 was highly expressed in early hematopoietic progenitors and reduced during cell differentiation, including the ATRA-induced granulocytic differentiation model. STMN1 phosphorylation was predominant in a pool of mitosis-enriched APL cells. In NB4 and NB4-R2 cells, STMN1 knockdown decreased autonomous cell growth (all p < 0.05) but did not impact ATRA-induced apoptosis and differentiation. Finally, treatment with paclitaxel (as a single agent or combined with ATRA) induced microtubule stabilization, resulting in mitotic catastrophe with repercussions for cell viability, even in ATRA-resistant APL cells. This study provides new insights into the STMN1 functions and microtubule dynamics in APL.

The Herbal Formula JI017 Induces ER Stress via Nox4 in Breast Cancer Cells

Chemotherapy is a powerful anti-tumor therapeutic strategy; however, resistance to treatment remains a serious concern. To overcome chemoresistance, combination therapy with anticancer drugs is a potential strategy. We developed a novel herbal extract, JI017, with lower toxicity and lesser side effects. JI017 induced programmed cell death and excessive unfolded protein response through the release of intracellular reactive oxygen species (ROS) and calcium in breast cancer cells. JI017 treatment increased the expression of endoplasmic reticulum (ER) stress markers, including p-PERK, p-eIF2α, ATF4, and CHOP, via the activation of both exosomal GRP78 and cell lysate GRP78. The ROS inhibitors diphenyleneiodonium and N-acetyl cysteine suppressed apoptosis and excessive ER stress by inhibiting Nox4 in JI017-treated breast cancer cells. Furthermore, in paclitaxel-resistant breast cancer cell lines, MCF-7R and MDA-MB-231R, a combination of JI017 and paclitaxel overcame paclitaxel resistance by blocking epithelial-mesenchymal transition (EMT) processes, such as the downregulation of E-cadherin expression and the upregulation of HIF-1α, vimentin, Snail, and Slug expression. These findings suggested that JI017 exerts a powerful anti-cancer effect in breast cancer and a combination therapy of JI017 and paclitaxel may be a potential cancer therapy for paclitaxel resistant breast cancer.

PGRMC1-dependent lipophagy promotes ferroptosis in paclitaxel-tolerant persister cancer cells

Background

Progesterone receptor membrane component 1 (PGRMC1) is a heme-binding protein inducing dimerization with cytochrome P450, which mediates chemoresistance. Increased PGRMC1 expression is found in multiple types of resistant cancers, but the role of PGRMC1 in the ferroptosis of cancer cells remains unrevealed. Therefore, we examined the role of PGRMC1 in promoting ferroptosis in paclitaxel-tolerant persister cancer cells (PCC).

Methods

The effects of ferroptosis inducers and PGRMC1 gene silencing/overexpression were tested on head and neck cancer (HNC) cell lines and mouse tumor xenograft models. The results were analyzed about cell viability, death, lipid ROS and iron production, mRNA/protein expression and interaction, and lipid assays.

Results

PCC had more free fatty acids, lipid droplets, and fatty acid oxidation (FAO) than their parental cells. PCC was highly sensitive to inhibitors of system xc⁻ cystine/glutamate antiporter (xCT), such as erastin, sulfasalazine, and cyst(e)ine deprivation, but less sensitive to (1S,3R)-RSL3. PGRMC1 silencing in PCC reduced ferroptosis sensitivity by xCT inhibitors, and PGRMC1 overexpression in parental cells increased ferroptosis by xCT inhibitors. Lipid droplets were degraded along with autophagy induction and autophagosome formation by erastin treatment in PCC. Lipophagy was accompanied by increased tubulin detyrosination, which was increased by SIRT1 activation but decreased by SIRT1 inhibition. FAO and lipophagy were also promoted by the interaction between lipid droplets and mitochondria.

Conclusion

PGRMC1 expression increased FAO and ferroptosis sensitivity from in vivo mice experiments. Our data suggest that PGRMC1 promotes ferroptosis by xCT inhibition in PCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02168-2.

Paclitaxel-tolerant persister cancer cells (PCC) had PGRMC1 upregulation related to increased free fatty acids, lipid droplets, and fatty acid oxidation. PGRMC1 expression substantially increased ferroptosis by xCT inhibition via lipophagy and tubulin detyrosination, whereas PGRMC1 silencing decreased ferroptosis: this suggests that PGRMC1 expression promotes ferroptosis in PCC.

Chitosan as possible inhibitory agents and delivery systems in leukemia

Leukemia is a lethal cancer in which white blood cells undergo proliferation and immature white blood cells are seen in the bloodstream. Without diagnosis and management in early stages, this type of cancer can be fatal. Changes in protooncogenic genes and microRNA genes are the most important factors involved in development of leukemia. At present, leukemia risk factors are not accurately identified, but some studies have pointed out factors that predispose to leukemia. Studies show that in the absence of genetic risk factors, leukemia can be prevented by reducing the exposure to risk factors of leukemia, including smoking, exposure to benzene compounds and high-dose radioactive or ionizing radiation. One of the most important treatments for leukemia is chemotherapy which has devastating side effects. Chemotherapy and medications used during treatment do not have a specific effect and destroy healthy cells besides leukemia cells. Despite the suppressing effect of chemotherapy against leukemia, patients undergoing chemotherapy have poor quality of life. So today, researchers are focusing on finding more safe and effective natural compounds and treatments for cancer, especially leukemia. Chitosan is a valuable natural compound that is biocompatible and non-toxic to healthy cells. Anticancer, antibacterial, antifungal and antioxidant effects are examples of chitosan biopolymer properties. The US Food and Drug Administration has approved the use of this compound in medical treatments and the pharmaceutical industry. In this article, we take a look at the latest advances in the use of chitosan in the treatment and improvement of leukemia.

Paclitaxel: Application in Modern Oncology and Nanomedicine-Based Cancer Therapy

Paclitaxel is a broad-spectrum anticancer compound, which was derived mainly from a medicinal plant, in particular, from the bark of the yew tree Taxus brevifolia Nutt. It is a representative of a class of diterpene taxanes, which are nowadays used as the most common chemotherapeutic agent against many forms of cancer. It possesses scientifically proven anticancer activity against, e.g., ovarian, lung, and breast cancers. The application of this compound is difficult because of limited solubility, recrystalization upon dilution, and cosolvent-induced toxicity. In these cases, nanotechnology and nanoparticles provide certain advantages such as increased drug half-life, lowered toxicity, and specific and selective delivery over free drugs. Nanodrugs possess the capability to buildup in the tissue which might be linked to enhanced permeability and retention as well as enhanced antitumour influence possessing minimal toxicity in normal tissues. This article presents information about paclitaxel, its chemical structure, formulations, mechanism of action, and toxicity. Attention is drawn on nanotechnology, the usefulness of nanoparticles containing paclitaxel, its opportunities, and also future perspective. This review article is aimed at summarizing the current state of continuous pharmaceutical development and employment of nanotechnology in the enhancement of the pharmacokinetic and pharmacodynamic features of paclitaxel as a chemotherapeutic agent.

7-Epitaxol Induces Apoptosis and Autophagy in Head and Neck Squamous Cell Carcinoma through Inhibition of the ERK Pathway

As the main derivative of paclitaxel, 7-Epitaxol is known to a have higher stability and cytotoxicity. However, the anticancer effect of 7-Epitaxol is still unclear. The purpose of this study was to explore the anticancer effects of 7-Epitaxol in squamous cell carcinoma of the head and neck (HNSCC). Our study findings revealed that 7-Epitaxol potently suppressed cell viability in SCC-9 and SCC-47 cells by inducing cell cycle arrest. Flow cytometry and DAPI staining demonstrated that 7-Epitaxol treatment induced cell death, mitochondrial membrane potential and chromatin condensation in OSCC cell lines. The compound regulated the proteins of extrinsic and intrinsic pathways at the highest concentration, and also increased the activation of caspases 3, 8, 9, and PARP in OSCC cell lines. Interestingly, a 7-Epitaxol-mediated induction of LC3-I/II expression and suppression of p62 expression were observed in OSCC cells lines. Furthermore, the MAPK inhibitors indicated that 7-Epitaxol induces apoptosis and autophagy marker proteins (cleaved-PARP and LC3-I/II) by reducing the phosphorylation of ERK1/2. In conclusion, these findings indicate the involvement of 7-Epitaxol in inducing apoptosis and autophagy through ERK1/2 signaling pathway, which identify 7-Epitaxol as a potent cytotoxic agent in HNSCC.