OBJECTIVES: To study the molecular mechanisms of LDH-loaded si-NEAT1 for regulating paclitaxel resistance and tumor-associated macrophage (TAM) polarization in breast cancer. METHODS: qRT-PCR and Western blotting were used to detect the expression of lncRNA NEAT1, miR-133b, and PD-L1 in breast cancer SKBR3 cells and paclitaxel-resistant SKBR3 cells (SKBR3-PR). The effects of transfection with si-NEAT1 and miR-133b mimics on MRP, MCRP and PD-L1 expressions and cell proliferation, migration and apoptosis were investigated using qRT-PCR, Western blotting, scratch and Transwell assays, and flow cytometry. Rescue experiments were conducted using si-NEAT1 and miR-133b inhibitor. Human THP-1 macrophages were cultured in the presence of conditioned media (CM) derived from SKBR3 and SKBR3-PR cells with or with si-NEAT1 transfection for comparison of IL-4-induced macrophage polarization by detecting the surface markers. LDH@si-NEAT1 nanocarriers were constructed, and their effects on MRP, MCRP and PD-L1 expressions and cell behaviors of the tumor cells were examined. THP-1 cells were treated with the CM from LDH@si-NEAT1-treated tumor cells, and the changes in their polarization were assessed. RESULTS: SKBR3-PR cells showered significantly upregulated NEAT1 and PD-L1 expressions and lowered miR-133b expression as compared with their parental cells. Transfection with si-NEAT1 and miR-133b mimics inhibited viability, promoted apoptosis and enhanced MRP and BCRP expressions in SKBR3-PR cells. NEAT1 knockdown obvious upregulated miR-133b and downregulated PD-L1, MRP and BCRP expressions. The CM from SKBR3-PR cells obviously promoted M2 polarization of THP-1 macrophages, which was significantly inhibited by CM from si-NEAT1-transfected cells. Treatment with LDH@si-NEAT1 effectively inhibited migration and invasion, promoted apoptosis, and reduced MRP, BCRP and PD-L1 expressions in the tumor cells. The CM from LDH@si-NEAT1-treated SKBR3-PR cells significantly downregulated Arg-1, CD163, IL-10, and PD-L1 and upregulated miR-133b expression in THP-1 macrophages. CONCLUSIONS LDH@si-NEAT1 reduces paclitaxel resistance of breast cancer cells and inhibits TAM polarization by targeting the miR-133b/PD-L1 axis.
Humans ; MicroRNAs/genetics* ; RNA, Long Noncoding/genetics* ; Paclitaxel/pharmacology* ; Breast Neoplasms/metabolism* ; Drug Resistance, Neoplasm ; B7-H1 Antigen/metabolism* ; Cell Line, Tumor ; Female ; Tumor-Associated Macrophages ; Apoptosis ; Cell Proliferation ; Macrophages ; Cell Movement

Paclitaxel (PTX), a valuable natural product derived from Taxus species, exhibits remarkable anti-cancer properties. It penetrates nanopores in microtubule walls, interacting with tubulin on the lumen surface and disrupting microtubule dynamics, thereby inducing cytotoxic effects in cancer cells. PTX and its derivatives have gained approval for treating various diseases due to their low toxicity, high efficiency, and broad-spectrum application. The widespread success and expanding applications of PTX have led to increased demand, raising concerns about accessibility. Consequently, researchers globally have focused on developing alternative production methods and applying nanocarriers in PTX delivery systems to enhance bioavailability. This review examines the challenges and advancements in PTX sourcing, production, physicochemical properties, anti-cancer mechanisms, clinical applications, trials, and chemo-immunotherapy. It aims to provide a comprehensive reference for the rational development and effective utilization of PTX.
Humans ; Paclitaxel/pharmacology* ; Antineoplastic Agents, Phytogenic/pharmacology* ; Neoplasms/drug therapy* ; Animals ; Taxus/chemistry*

Cancer multidrug resistance (MDR) impairs the therapeutic efficacy of various chemotherapeutics. Novel approaches, particularly the development of MDR reversal agents, are critically needed to address this challenge. This study demonstrates that tenacissoside I (TI), a compound isolated from Marsdenia tenacissima (Roxb.) Wight et Arn, traditionally used in clinical practice as an ethnic medicine for cancer treatment, exhibits significant MDR reversal effects in ABCB1-mediated MDR cancer cells. TI reversed the resistance of SW620/AD300 and KBV200 cells to doxorubicin (DOX) and paclitaxel (PAC) by downregulating ABCB1 expression and reducing ABCB1 drug transport function. Mechanistically, protein arginine methyltransferase 1 (PRMT1), whose expression correlates with poor prognosis and shows positive association with both ABCB1 and EGFR expressions in tumor tissues, was differentially expressed in TI-treated SW620/AD300 cells. SW620/AD300 and KBV200 cells exhibited elevated levels of EGFR asymmetric dimethylarginine (aDMA) and enhanced PRMT1-EGFR interaction compared to their parental cells. Moreover, TI-induced PRMT1 downregulation impaired PRMT1-mediated aDMA of EGFR, PRMT1-EGFR interaction, and EGFR downstream signaling in SW620/AD300 and KBV200 cells. These effects were significantly reversed by PRMT1 overexpression. Additionally, TI demonstrated resistance reversal to PAC in xenograft models without detectable toxicities. This study establishes TI's MDR reversal effect in ABCB1-mediated MDR human cancer cells through inhibition of PRMT1-mediated aDMA of EGFR, suggesting TI's potential as an MDR modulator for improving chemotherapy outcomes.
Humans ; Protein-Arginine N-Methyltransferases/antagonists & inhibitors* ; Drug Resistance, Neoplasm/drug effects* ; ErbB Receptors/genetics* ; Animals ; Cell Line, Tumor ; Drug Resistance, Multiple/drug effects* ; Methylation/drug effects* ; Saponins/administration & dosage* ; Mice ; Mice, Nude ; Mice, Inbred BALB C ; ATP Binding Cassette Transporter, Subfamily B/genetics* ; Doxorubicin/pharmacology* ; Paclitaxel/pharmacology* ; Female ; Repressor Proteins

Objective To investigate the effects of paclitaxel and doxorubicin on the immune microenvironment of breast cancer in mice. Methods The CTR-DB database, a database for analysis of gene expression profiles and drug resistance characteristics related to tumor drug response, was used to analyze the effect of chemotherapeutic drugs on the immune microenvironment of breast cancer. Mouse models with breast cancer were established by in situ injection with 4T1 cells, a triple-negative breast cancer (TNBC) cells. Then they were treated with doxorubicin and paclitaxel, respectively. The sizes of tumor were recorded and analyzed by growth curve. The number of different types of immune cells was analyzed using flow cytometry. The expressions of Ki67, S100 calcium binding protein A9 (S100A9) and matrix metalloproteinase 9 (MMP9) were detected by immunohistochemistry. The cell cycles of 4T1 cells in paclitaxel group and doxorubicin group were analyzed by flow cytometry. Results The results of CTR_Microarray_75 analysis showed that the immune scores, and the number of cytotoxic lymphocytes, B lineages, CD8⁺ T cells, dendritic cells (DCs), monocytic lineages and natural killer (NK) cells in chemotherapy-sensitive breast cancer were higher than those in chemotherapy-insensitive breast cancer. Through growth curve analysis in mice with breast cancer, we found that both paclitaxel and doxorubicin could inhibit the increase of the tumor sizes, and the paclitaxel showed a higher inhibitory effect. The results of cytometry displayed that both paclitaxel and doxorubicin could restrain the expression of Ki67 and increase the number of breast cancer cells in G2/M phase, and in the paclitaxel group, the expression of Ki67 was lower and the number of breast cancer cells in G2/M phase was larger. Paclitaxel and doxorubicin enhanced the infiltration of CD45⁺ immune cells but decreased the infiltration of neutrophils. Additionally, paclitaxel promoted the infiltration of CD3⁺CD4⁺ T helper cells, CD3⁺CD8⁺ cytotoxic T cells and CD45⁺CD19⁺B cells, while doxorubicin increased the infiltration of CD4⁺CD25⁺ regulatory T cells (Tregs). The results of immunohistochemistry displayed that the paclitaxel significantly inhibited the expression of S100A9, while the doxorubicin significantly restrained the expression of MMP9. Conclusion Paclitaxel and doxorubicin can effectively inhibit the growth of breast cancer cells and change immune microenvironment of TNBC by regulating the different patterns of cell infiltration and the expression of different extracellular matrix components.
Animals ; Mice ; Humans ; Paclitaxel/pharmacology* ; Matrix Metalloproteinase 9 ; Triple Negative Breast Neoplasms/drug therapy* ; CD8-Positive T-Lymphocytes ; Ki-67 Antigen ; Doxorubicin/pharmacology* ; Calgranulin B ; Tumor Microenvironment

Ginsenoside Rg_3, an active component of traditional Chinese medicine(TCM), was used as the substitute for cholesterol as the membrane material to prepare the ginsenoside Rg_3-based liposomes loaded with dihydroartemisinin and paclitaxel. The effect of the prepared drug-loading liposomes on triple-negative breast cancer in vitro was evaluated. Liposomes were prepared with the thin film hydration method, and the preparation process was optimized by single factor experiments. The physicochemical properties(e.g., particle size, Zeta potential, and stability) of the liposomes were characterized. The release behaviors of drugs in different media(pH 5.0 and pH 7.4) were evaluated. The antitumor activities of the liposomes were determined by CCK-8 on MDA-MB-231 and 4T1 cells. The cell scratch test was carried out to evaluate the effect of the liposomes on the migration of MDA-MB-231 and 4T1 cells. Further, the targeting ability of liposomes and the mechanism of lysosome escape were investigated. Finally, H9c2 cells were used to evaluate the potential cardiotoxicity of the preparation. The liposomes prepared were spheroid, with uniform particle size distribution, the ave-rage particle size of(107.81±0.01) nm, and the Zeta potential of(2.78±0.66) mV. The encapsulation efficiency of dihydroartemisinin and paclitaxel was 57.76%±1.38% and 99.66%±0.07%, respectively, and the total drug loading was 4.46%±0.71%. The accumulated release of dihydroartemisinin and paclitaxel from the liposomes at pH 5.0 was better than that at pH 7.4, and the liposomes could be stored at low temperature for seven days with good stability. Twenty-four hours after administration, the inhibition rates of the ginsenoside Rg_3-based liposomes loaded with dihydroartemisinin(70 μmol·L~(-1)) and paclitaxel on MDA-MB-231 and 4T1 cells were higher than those of the positive control(adriamycin) and free drugs(P<0.01). Compared with free drugs, liposomes inhibited the migration of MDA-MB-231 and 4T1 cells(P<0.05). Liposomes demonstrated active targeting and lysosome escape. In particular, liposomes showed lower toxicity to H9c2 cells than free drugs(P<0.05), which indicated that the preparation had the potential to reduce cardiotoxicity. The findings prove that ginsenoside Rg_3 characterized by the combination of drug and excipient is an ideal substitute for lipids in liposomes and promoted the development of innovative TCM drugs for treating cancer.
Humans ; Paclitaxel/pharmacology* ; Liposomes/chemistry* ; Ginsenosides/therapeutic use* ; Triple Negative Breast Neoplasms/drug therapy* ; Cardiotoxicity/drug therapy* ; Cell Line, Tumor

OBJECTIVES: Primary tumor treatment through surgical resection and adjuvant therapy has been extensively studied, but there is a lack of effective strategies and drugs for the treatment of tumor metastases. Here, we describe a functional product based on a combination of compounds, which can be used as an adjuvant therapy and has well-known mechanisms for inhibiting cancer metastases, improving anti-cancer treatment, and enhancing immunity and antioxidant capacity. Our designed combination, named MVBL, consists of four inexpensive compounds: L-selenium-methylselenocysteine (MSC), D-‍α‍-tocopheryl succinic acid (VES), β‍-carotene (β‍-Ca), and L-lysine (Lys). METHODS: The effects of MVBL on cell viability, cell cycle, cell apoptosis, cell migration, cell invasion, reactive oxygen species (ROS), and paclitaxel (PTX)-combined treatment were studied in vitro. The inhibition of tumor metastasis, antioxidation, and immune enhancement capacity of MVBL were determined in vivo. RESULTS: MVBL exhibited higher toxicity to tumor cells than to normal cells. It did not significantly affect the cell cycle of cancer cells, but increased their apoptosis. Wound healing, adhesion, and transwell assays showed that MVBL significantly inhibited tumor cell migration, adhesion, and invasion. MVBL sensitized MDA-MB-231 breast cancer cells to PTX, indicating that it can be used as an adjuvant to enhance the therapeutic effect of chemotherapy drugs. In mice, experimental data showed that MVBL inhibited tumor metastasis, prolonged their survival time, and enhanced their antioxidant capacity and immune function. CONCLUSIONS This study revealed the roles of MVBL in improving immunity and antioxidation, preventing tumor growth, and inhibiting metastasis in vitro and in vivo. MVBL may be used as an adjuvant drug in cancer therapy for improving the survival and quality of life of cancer patients.
Mice ; Animals ; beta Carotene ; Lysine/pharmacology* ; Antioxidants/pharmacology* ; Quality of Life ; Paclitaxel/pharmacology* ; Apoptosis ; alpha-Tocopherol ; Succinates/pharmacology* ; Cell Line, Tumor ; Cell Proliferation ; Neoplasms

Objective: To explore the effect of dormant polyploid giant cancer cells (PGCC) on nasopharyngeal carcinoma (NPC) recurrence and to clarify the role of inhibition of autophagy in inhibiting NPC-PGCC formation and preventing NPC recurrence. Methods: NPC cells-derived PGCC (NPC-PGCC) were induced by paclitaxel (PTX), and the morphology, polyploid characteristics and cell activity of PGCC were identified by light microscopy, immunofluorescence and Live/Dead cell double staining assays. RNA-seq was used to analyze the differentially expressed genes between NPC-PGCC and diploid nasopharyngeal carcinoma cells CNE2. Functional enrichment and pathway annotation analysis of differentially expressed genes were performed using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG). The level of autophagy in NPC-PGCC cells was assessed by Western Blot and transmission electron microscopy analysis. The role of autophagy in the formation of NPC-PGCC and the effect of NPC-PGCC on the recurrence of nasopharyngeal carcinoma were studied using a highly clinically relevant mouse nasopharyngeal carcinoma recurrence model. Statistical analysis was performed using GraphPad Prism 6 and P-values<0.05 were considered statistically significant. Results: NPC-PGCC induced by paclitaxel had the characteristics of burst-like division after dormancy. GO enrichment and KEGG pathway analyses identified the significant biological processes and pathways mainly concentrated in autophagy and related pathways involving the differentially expressed genes between NPC-PGCC and diploid nasopharyngeal carcinoma cells CNE2. The autophagy level was significantly enhanced in NPC-PGCC cells. In a highly clinically relevant mouse nasopharyngeal carcinoma recurrence model, the number of PGCC in the primary tumor of the nude mice treated with cisplatin were higher than those of the other groups. In nude mice pretreated with autophagy inhibitor and then co-treatment with autophagy inhibitor and cisplatin, the number of PGCC in primary tumors was less and the recurrence rate was significantly lower than in other groups. Conclusions: The mechanism of dormant polyploid giant cancer cells formation is related to autophagy. Inhibition of autophagy can inhibit the formation of PGCC and thus prevent the recurrence of nasopharyngeal carcinoma.
Animals ; Autophagy ; Carcinoma/genetics* ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Cisplatin/pharmacology* ; Gene Expression Regulation, Neoplastic ; Mice ; Mice, Nude ; Nasopharyngeal Carcinoma/genetics* ; Nasopharyngeal Neoplasms/pathology* ; Paclitaxel/pharmacology* ; Polyploidy

OBJECTIVE: To examine the role of miR-16-5p in regulating biological behaviors of paclitaxel- resistant breast cancer cells and its molecular mechanism. METHODS: The expression of miR-16-5p was examined in 13 pairs of breast cancer and adjacent tissues and in parental SKBR-3 cells and paclitaxel-resistant SKBR-3/PR cells using qRT-PCR. The target genes of miR-16- 5p were predicted by bioinformatic analysis, and their targeted binding was tested using luciferase assay. The cells were transfected with a miR-16-5p mimics, a miR-16-5p inhibitor, a specific siRNA targeting YWHAQ (si-YWHAQ), or both the miR-16-5p mimics and si-YWHAQ, and the changes in cellular expressions of YWHAQ, Bcl-2 and Bax were detected using Western blot. The changes in proliferation and migration of the cells were evaluated with CCK-8 assay and Transwell assay, and the cell cycle changes and cell apoptosis were analyzed with flow cytometry. RESULTS: The expression of miR-16-5p was significantly lower in breast cancer tissues than in paired adjacent tissues (P < 0.01). Bioinformatic analysis predicted that YWHAQ was the target gene of miR-16-5p, which was confirmed by luciferase assay. Compared with parental SKBR- 3 cells, SKBR- 3/PR cells showed a lowered level of miR-16-5p expression and an increased expression of YWHAQ. Transfection with the miR-16-5p mimics significantly inhibited YWHAQ expression (P < 0.01), while miR-16-5p inhibitor promoted YWHAQ expression in SKBR-3/PR cells (P < 0.01). The miR-16-5p mimics caused cell cycle arrest in G0/G1 phase (P < 0.0l), suppressed proliferation and migration, and increased apoptosis rate of SKBR-3/PR cells (P < 0.0l). Knocking down YWHAQ also reduced the migration ability of SKBR-3/PR cells and increased cell apoptosis rate. Transfection with either miR-16-5p mimics or si-YWHAQ resulted in increased Bax expression and lowered expressions of YWHAQ and Bcl-2 in the cells. The cells transfected with both miR-16-5p mimics and si-YWHAQ showed obviously suppressed cell migration (P < 0.01) and significantly increased apoptosis rate (P < 0.01). CONCLUSION miR-16-5p can modulate the expressions of Bcl- 2 and Bax by targeted regulation of YWHAQ to modify the biological behaviors of paclitaxel-resistant breast cancer cells.
Humans ; Female ; Breast Neoplasms/metabolism* ; bcl-2-Associated X Protein/metabolism* ; Cell Line, Tumor ; MicroRNAs/metabolism* ; Apoptosis ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Cell Movement ; Paclitaxel/pharmacology* ; Cell Proliferation ; Gene Expression Regulation, Neoplastic

OBJECTIVE: To construct a polylactic acid-glycolic acid-polyethylene glycol (PLGA-PEG) nanocarrier (N-Pac-CD133) coupled with a CD133 nucleic acid aptamer carrying paclitaxel for eliminating lung cancer stem cells (CSCs). METHODS: Paclitaxel-loaded N-Pac-CD133 was prepared using the emulsion/solvent evaporation method and characterized. CD133⁺ lung CSCs were separated by magnetic bead separation and identified for their biological behaviors and gene expression profile. The efficiency of paclitaxel-loaded N-Pac-CD133 for targeted killing of lung cancer cells was assessed in vitro. SCID mice were inoculated with A549 cells and received injections of normal saline, empty nanocarrier linked with CD133 aptamer (N-CD133), paclitaxel, paclitaxel-loaded nanocarrier (N-Pac) or paclitaxel-loaded N-Pac-CD133 (n=8, 5 mg/kg paclitaxel) on days 10, 15 and 20, and the tumor weight and body weight of the mice were measured on day 40. RESULTS: Paclitaxel-loaded N-Pac-CD133 showed a particle size of about 100 nm with a high encapsulation efficiency (>80%) and drug loading rate (>8%), and was capable of sustained drug release within 48 h. The CD133⁺ cell population in lung cancer cells showed the characteristic features of lung CSCs, including faster growth rate (30 days, P=0.001) and high expressions of tumor stem cell markers OV6(P < 0.001), CD133 (P=0.001), OCT3/4 (P=0.002), EpCAM (P=0.04), NANOG (P=0.005) and CD44 (P=0.02). Compared with N-Pac and free paclitaxel, paclitaxel-loaded N-Pac-CD133 showed significantly enhanced targeting ability and cytotoxicity against lung CSCs in vitro (P < 0.001) and significantly reduced the formation of tumor spheres (P < 0.001). In the tumor-bearing mice, paclitaxel-loaded N-Pac-CD133 showed the strongest effects in reducing the tumor mass among all the treatments (P < 0.001). CONCLUSION CD133 aptamer can promote targeted delivery of paclitaxel to allow targeted killing of CD133⁺ lung CSCs. N-Pac-CD133 loaded with paclitaxel may provide an effective treatment for lung cancer by targeting the lung cancer stem cells.
Animals ; Cell Line, Tumor ; Drug Carriers ; Lung ; Mice ; Mice, SCID ; Nanoparticles ; Neoplasms ; Neoplastic Stem Cells ; Paclitaxel/pharmacology* ; Polyethylene Glycols/pharmacology*

OBJECTIVE: To investigate the effects of paclitaxel, quizartinib and their combination on proliferation, apoptosis and FLT3/STAT5 pathway of human leukemia cell line MV4-11 (FLT3-ITD+). METHODS: MV4-11 cells were treated with paclitaxel and quizartinib at different concentrations for 24 h, 48 h and 72 h, respectively, and then the two drugs were combined at 48 h to compare the inhibition of proliferation, the apoptosis rate was detected by flow cytometry, the expression of FLT3 and STAT5 mRNA was determined by fluorescence quantitative PCR, and the protein expression of FLT3, p-FLT3, STAT5 and p-STAT5 was determined by Western blot. RESULTS: Different combination groups of paclitaxel and quizartinib had synergistic inhibitory effect. The cell survival rate in the combination group was significantly lower than that in the single drug group (P<0.05). The cell apoptosis rate in the combination group was significantly higher than that in the single drug group (P<0.001). The expression of FLT3 mRNA in combination group was significantly higher than that in two single drugs (P<0.01). The expression of STAT5 mRNA in combination group was significantly higher than that in quizartinib group (P<0.001); increased compared with paclitaxel group, but there was no statistical significance. The expression level of p-FLT3、p-STAT5 protein in the combination group was significantly lower than that in the single drug group (P<0.05, P<0.05). CONCLUSION Paclitaxel combined with quizartinib can synergistically inhibit the proliferation of MV4-11 cell line and promote the apoptosis of MV4-11 cell line by inhibiting the activity of FLT3/STAT5 pathway.
Apoptosis ; Benzothiazoles ; Cell Line, Tumor ; Humans ; Leukemia, Myeloid, Acute/genetics* ; Paclitaxel/therapeutic use* ; Phenylurea Compounds ; RNA, Messenger ; STAT5 Transcription Factor/pharmacology* ; Signal Transduction ; fms-Like Tyrosine Kinase 3