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Molecular Plant Dec 2023The diterpenoid paclitaxel (Taxol) is a chemotherapy medication widely used as a first-line treatment against several types of solid cancers. The supply of paclitaxel...
The diterpenoid paclitaxel (Taxol) is a chemotherapy medication widely used as a first-line treatment against several types of solid cancers. The supply of paclitaxel from natural sources is limited. However, missing knowledge about the genes involved in several specific metabolic steps of paclitaxel biosynthesis has rendered it difficult to engineer the full pathway. In this study, we used a combination of transcriptomics, cell biology, metabolomics, and pathway reconstitution to identify the complete gene set required for the heterologous production of paclitaxel. We identified the missing steps from the current model of paclitaxel biosynthesis and confirmed the activity of most of the missing enzymes via heterologous expression in Nicotiana benthamiana. Notably, we identified a new C4β-C20 epoxidase that could overcome the first bottleneck of metabolic engineering. We used both previously characterized and newly identified oxomutases/epoxidases, taxane 1β-hydroxylase, taxane 9α-hydroxylase, taxane 9α-dioxygenase, and phenylalanine-CoA ligase, to successfully biosynthesize the key intermediate baccatin III and to convert baccatin III into paclitaxel in N. benthamiana. In combination, these approaches establish a metabolic route to taxoid biosynthesis and provide insights into the unique chemistry that plants use to generate complex bioactive metabolites.
Topics: Synthetic Biology; Taxoids; Paclitaxel; Mixed Function Oxygenases
PubMed: 37897038
DOI: 10.1016/j.molp.2023.10.016 -
Cancer Discovery Sep 2023Most circulating tumor cells (CTC) are detected as single cells, whereas a small proportion of CTCs in multicellular clusters with stemness properties possess 20- to...
UNLABELLED
Most circulating tumor cells (CTC) are detected as single cells, whereas a small proportion of CTCs in multicellular clusters with stemness properties possess 20- to 100-times higher metastatic propensity than the single cells. Here we report that CTC dynamics in both singles and clusters in response to therapies predict overall survival for breast cancer. Chemotherapy-evasive CTC clusters are relatively quiescent with a specific loss of ST6GAL1-catalyzed α2,6-sialylation in glycoproteins. Dynamic hyposialylation in CTCs or deficiency of ST6GAL1 promotes cluster formation for metastatic seeding and enables cellular quiescence to evade paclitaxel treatment in breast cancer. Glycoproteomic analysis reveals newly identified protein substrates of ST6GAL1, such as adhesion or stemness markers PODXL, ICAM1, ECE1, ALCAM1, CD97, and CD44, contributing to CTC clustering (aggregation) and metastatic seeding. As a proof of concept, neutralizing antibodies against one newly identified contributor, PODXL, inhibit CTC cluster formation and lung metastasis associated with paclitaxel treatment for triple-negative breast cancer.
SIGNIFICANCE
This study discovers that dynamic loss of terminal sialylation in glycoproteins of CTC clusters contributes to the fate of cellular dormancy, advantageous evasion to chemotherapy, and enhanced metastatic seeding. It identifies PODXL as a glycoprotein substrate of ST6GAL1 and a candidate target to counter chemoevasion-associated metastasis of quiescent tumor cells. This article is featured in Selected Articles from This Issue, p. 1949.
Topics: Humans; Female; Breast Neoplasms; Neoplastic Cells, Circulating; Paclitaxel; Triple Negative Breast Neoplasms; Glycoproteins; Biomarkers, Tumor; Neoplasm Metastasis
PubMed: 37272843
DOI: 10.1158/2159-8290.CD-22-0644 -
Journal of Thoracic Oncology : Official... Aug 2020Cytotoxic agents have immunomodulatory effects, providing a rationale for combining atezolizumab (anti-programmed death-ligand 1 [anti-PD-L1]) with chemotherapy. The... (Randomized Controlled Trial)
Randomized Controlled Trial
INTRODUCTION
Cytotoxic agents have immunomodulatory effects, providing a rationale for combining atezolizumab (anti-programmed death-ligand 1 [anti-PD-L1]) with chemotherapy. The randomized phase III IMpower131 study (NCT02367794) evaluated atezolizumab with platinum-based chemotherapy in stage IV squamous NSCLC.
METHODS
A total of 1021 patients were randomized 1:1:1 to receive atezolizumab+carboplatin+paclitaxel (A+CP) (n = 338), atezolizumab+carboplatin+nab-paclitaxel (A+CnP) (n = 343), or carboplatin+nab-paclitaxel (CnP) (n = 340) for four or six 21-day cycles; patients randomized to the A+CP or A+CnP arms received atezolizumab maintenance therapy until progressive disease or loss of clinical benefit. The coprimary end points were investigator-assessed progression-free survival (PFS) and overall survival (OS) in the intention-to-treat (ITT) population. The secondary end points included PFS and OS in PD-L1 subgroups and safety. The primary PFS (January 22, 2018) and final OS (October 3, 2018) for A+CnP versus CnP are reported.
RESULTS
PFS improvement with A+CnP versus CnP was seen in the ITT population (median, 6.3 versus 5.6 mo; hazard ratio [HR] = 0.71, 95% confidence interval [CI]: 0.60-0.85; p = 0.0001). Median OS in the ITT population was 14.2 and 13.5 months in the A+CnP and CnP arms (HR = 0.88, 95% CI: 0.73-1.05; p = 0.16), not reaching statistical significance. OS improvement with A+CnP versus CnP was observed in the PD-L1-high subgroup (HR = 0.48, 95% CI: 0.29-0.81), despite not being formally tested. Treatment-related grade 3 and 4 adverse events and serious adverse events occurred in 68.0% and 47.9% (A+CnP) and 57.5% and 28.7% (CnP) of patients, respectively.
CONCLUSIONS
Adding atezolizumab to platinum-based chemotherapy significantly improved PFS in patients with first-line squamous NSCLC; OS was similar between the arms.
Topics: Albumins; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Carboplatin; Carcinoma, Squamous Cell; Humans; Lung Neoplasms; Paclitaxel
PubMed: 32302702
DOI: 10.1016/j.jtho.2020.03.028 -
Blood Jun 2022Tumor-associated macrophages (TAMs) are often the most abundant immune cells in the tumor microenvironment (TME). Strategies targeting TAMs to enable tumor cell killing...
Tumor-associated macrophages (TAMs) are often the most abundant immune cells in the tumor microenvironment (TME). Strategies targeting TAMs to enable tumor cell killing through cellular phagocytosis have emerged as promising cancer immunotherapy. Although several phagocytosis checkpoints have been identified, the desired efficacy has not yet been achieved by blocking such checkpoints in preclinical models or clinical trials. Here, we showed that late-stage non-Hodgkin lymphoma (NHL) was resistant to therapy targeting phagocytosis checkpoint CD47 due to the compromised capacity of TAMs to phagocytose lymphoma cells. Via a high-throughput screening of the US Food and Drug Administration-approved anticancer small molecule compounds, we identified paclitaxel as a potentiator that promoted the clearance of lymphoma by directly evoking phagocytic capability of macrophages, independently of paclitaxel's chemotherapeutic cytotoxicity toward NHL cells. A combination with paclitaxel dramatically enhanced the anticancer efficacy of CD47-targeted therapy toward late-stage NHL. Analysis of TME by single-cell RNA sequencing identified paclitaxel-induced TAM populations with an upregulation of genes for tyrosine kinase signaling. The activation of Src family tyrosine kinases signaling in macrophages by paclitaxel promoted phagocytosis against NHL cells. In addition, we identified a role of paclitaxel in modifying the TME by preventing the accumulation of a TAM subpopulation that was only present in late-stage lymphoma resistant to CD47-targeted therapy. Our findings identify a novel and effective strategy for NHL treatment by remodeling TME to enable the tumoricidal roles of TAMs. Furthermore, we characterize TAM subgroups that determine the efficiency of lymphoma phagocytosis in the TME and can be potential therapeutic targets to unleash the antitumor activities of macrophages.
Topics: CD47 Antigen; Humans; Immunosuppression Therapy; Immunotherapy; Lymphoma; Macrophages; Neoplasms; Paclitaxel; Phagocytosis; Tumor Microenvironment
PubMed: 35134139
DOI: 10.1182/blood.2021013901 -
Science Translational Medicine May 2022Immunomodulators that remodel the tumor immunosuppressive microenvironment have been combined with anti-programmed death 1 (α-PD1) or anti-programmed death ligand 1...
Immunomodulators that remodel the tumor immunosuppressive microenvironment have been combined with anti-programmed death 1 (α-PD1) or anti-programmed death ligand 1 (α-PDL1) immunotherapy but have shown limited success in clinical trials. However, therapeutic strategies to modulate the immunosuppressive microenvironment of lymph nodes have been largely overlooked. Here, we designed an albumin nanoparticle, Nano-PI, containing the immunomodulators PI3Kγ inhibitor (IPI-549) and paclitaxel (PTX). We treated two breast cancer mouse models with Nano-PI in combination with α-PD1, which remodeled the tumor microenvironment in both lymph nodes and tumors. This combination achieved long-term tumor remission in mouse models and eliminated lung metastases. PTX combined with IPI-549 enabled the formation of a stable nanoparticle and enhanced the repolarization of M2 to M1 macrophages. Nano-PI not only enhanced the delivery of both immunomodulators to lymph nodes and tumors but also improved the drug accumulation in the macrophages of these two tissues. Immune cell profiling revealed that the combination of Nano-PI with α-PD1 remodeled the immune microenvironment by polarizing M2 to M1 macrophages, increasing CD4 and CD8 T cells, B cells, and dendritic cells, decreasing regulatory T cells, and preventing T cell exhaustion. Our data suggest that Nano-PI in combination with α-PD1 modulates the immune microenvironment in both lymph nodes and tumors to achieve long-term remission in mice with metastatic breast cancer, and represents a promising candidate for future clinical trials.
Topics: Albumins; Animals; Breast Neoplasms; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Female; Humans; Mice; Nanoparticles; Paclitaxel; Tumor Microenvironment
PubMed: 35507675
DOI: 10.1126/scitranslmed.abl3649 -
Gastric Cancer : Official Journal of... Jan 2022In the phase 3 KEYNOTE-061 study (cutoff: 10/26/2017), pembrolizumab did not significantly prolong OS vs paclitaxel as second-line (2L) therapy in PD-L1 combined... (Randomized Controlled Trial)
Randomized Controlled Trial
Pembrolizumab versus paclitaxel for previously treated PD-L1-positive advanced gastric or gastroesophageal junction cancer: 2-year update of the randomized phase 3 KEYNOTE-061 trial.
BACKGROUND
In the phase 3 KEYNOTE-061 study (cutoff: 10/26/2017), pembrolizumab did not significantly prolong OS vs paclitaxel as second-line (2L) therapy in PD-L1 combined positive score (CPS) ≥ 1 gastric/GEJ cancer. We present results in CPS ≥ 1, ≥ 5, and ≥ 10 populations after two additional years of follow-up (cutoff: 10/07/2019).
METHODS
Patients were randomly allocated 1:1 to pembrolizumab 200 mg Q3W for ≤ 35 cycles or standard-dose paclitaxel. Primary endpoints: OS and PFS (CPS ≥ 1 population). HRs were calculated using stratified Cox proportional hazards models.
RESULTS
366/395 patients (92.7%) with CPS ≥ 1 died. Pembrolizumab demonstrated a trend toward improved OS vs paclitaxel in the CPS ≥ 1 population (HR, 0.81); 24-month OS rates: 19.9% vs 8.5%. Pembrolizumab incrementally increased the OS benefit with PD-L1 enrichment (CPS ≥ 5: HR, 0.72, 24-month rate, 24.2% vs 8.8%; CPS ≥ 10: 0.69, 24-month rate, 32.1% vs 10.9%). There was no difference in median PFS among treatment groups (CPS ≥ 1: HR, 1.25; CPS ≥ 5: 0.98; CPS ≥ 10: 0.79). ORR (pembrolizumab vs paclitaxel) was 16.3% vs 13.6% (CPS ≥ 1), 20.0% vs 14.3% (CPS ≥ 5), and 24.5% vs 9.1% (CPS ≥ 10); median DOR was 19.1 months vs 5.2, 32.7 vs 4.8, and NR vs 6.9, respectively. Fewer treatment-related AEs (TRAEs) occurred with pembrolizumab than paclitaxel (53% vs 84%).
CONCLUSION
In this long-term analysis, 2L pembrolizumab did not significantly improve OS but was associated with higher 24-month OS rates than paclitaxel. Pembrolizumab also increased OS benefit with PD-L1 enrichment among patients with PD-L1-positive gastric/GEJ cancer and led to fewer TRAEs than paclitaxel.
TRIAL REGISTRATION
ClinicalTrials.gov, NCT02370498.
Topics: Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; B7-H1 Antigen; Esophagogastric Junction; Humans; Paclitaxel; Stomach Neoplasms
PubMed: 34468869
DOI: 10.1007/s10120-021-01227-z -
Journal of Translational Medicine Jun 2022Triple negative breast cancer (TNBC) is an aggressive disease characterized by high risk of relapse and development of resistance to different chemotherapy agents....
Inhibition of autophagy by chloroquine prevents resistance to PI3K/AKT inhibitors and potentiates their antitumor effect in combination with paclitaxel in triple negative breast cancer models.
BACKGROUND
Triple negative breast cancer (TNBC) is an aggressive disease characterized by high risk of relapse and development of resistance to different chemotherapy agents. Several targeted therapies have been investigated in TNBC with modest results in clinical trials. Among these, PI3K/AKT inhibitors have been evaluated in addition to standard therapies, yielding conflicting results and making attempts on elucidating inherent mechanisms of resistance of great interest. Increasing evidences suggest that PI3K/AKT inhibitors can induce autophagy in different cancers. Autophagy represents a supposed mechanism of drug-resistance in aggressive tumors, like TNBC. We, therefore, investigated if two PI3K/AKT inhibitors, ipatasertib and taselisib, could induce autophagy in breast cancer models, and whether chloroquine (CQ), a well known autophagy inhibitor, could potentiate ipatasertib and taselisib anti-cancer effect in combination with conventional chemotherapy.
METHODS
The induction of autophagy after ipatasertib and taselisib treatment was evaluated in MDAMB231, MDAM468, MCF7, SKBR3 and MDAB361 breast cancer cell lines by assaying LC3-I conversion to LC3-II through immunoblotting and immunofluorescence. Other autophagy-markers as p62/SQSTM1 and ATG5 were evaluated by immunoblotting. Synergistic antiproliferative effect of double and triple combinations of ipatasertib/taselisib plus CQ and/or paclitaxel were evaluated by SRB assay and clonogenic assay. Anti-apoptotic effect of double combination of ipatasertib/taselisib plus CQ was evaluated by increased cleaved-PARP by immunoblot and by Annexin V- flow cytometric analysis. In vivo experiments were performed on xenograft model of MDAMB231 in NOD/SCID mice.
RESULTS
Our results suggested that ipatasertib and taselisib induce increased autophagy signaling in different breast cancer models. This effect was particularly evident in PI3K/AKT resistant TNBC cells, where the inhibition of autophagy by CQ potentiates the therapeutic effect of PI3K/AKT inhibitors in vitro and in vivo TNBC models, synergizing with taxane-based chemotherapy.
CONCLUSION
These data suggest that inhibition of authophagy with CQ could overcome mechanism of drug resistance to PI3K/AKT inhibitors plus paclitaxel in TNBC making the evaluation of such combinations in clinical trials warranted.
Topics: Animals; Autophagy; Cell Line, Tumor; Cell Proliferation; Chloroquine; Drug Resistance, Neoplasm; Humans; Mice; Mice, Inbred NOD; Mice, SCID; Paclitaxel; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Triple Negative Breast Neoplasms
PubMed: 35761360
DOI: 10.1186/s12967-022-03462-z -
Molecular Cancer Therapeutics Nov 2023Immune checkpoint inhibition combined with chemotherapy is currently approved as first-line treatment for patients with advanced PD-L1-positive triple-negative breast...
Immune checkpoint inhibition combined with chemotherapy is currently approved as first-line treatment for patients with advanced PD-L1-positive triple-negative breast cancer (TNBC). However, a significant proportion of metastatic TNBC is PD-L1-negative and, in this population, chemotherapy alone largely remains the standard-of-care and novel therapeutic strategies are needed to improve clinical outcomes. Here, we describe a triple combination of anti-PD-L1 immune checkpoint blockade, epigenetic modulation thorough bromodomain and extra-terminal (BET) bromodomain inhibition (BBDI), and chemotherapy with paclitaxel that effectively inhibits both primary and metastatic tumor growth in two different syngeneic murine models of TNBC. Detailed cellular and molecular profiling of tumors from single and combination treatment arms revealed increased T- and B-cell infiltration and macrophage reprogramming from MHCIIlow to a MHCIIhigh phenotype in mice treated with triple combination. Triple combination also had a major impact on gene expression and chromatin profiles shifting cells to a more immunogenic and senescent state. Our results provide strong preclinical evidence to justify clinical testing of BBDI, paclitaxel, and immune checkpoint blockade combination.
Topics: Humans; Animals; Mice; Triple Negative Breast Neoplasms; B7-H1 Antigen; Immune Checkpoint Inhibitors; Nuclear Proteins; Transcription Factors; Paclitaxel; Immunotherapy
PubMed: 37676980
DOI: 10.1158/1535-7163.MCT-23-0303 -
Oncogene Jul 2022Despite paclitaxel's wide use in cancer treatment, patient response rate is still low and drug resistance is a major clinical obstacle. Through a Phos-tag-based...
Despite paclitaxel's wide use in cancer treatment, patient response rate is still low and drug resistance is a major clinical obstacle. Through a Phos-tag-based kinome-wide screen, we identified MARK2 as a critical regulator for paclitaxel chemosensitivity in PDAC. We show that MARK2 is phosphorylated by CDK1 in response to antitubulin chemotherapeutics and in unperturbed mitosis. Phosphorylation is essential for MARK2 in regulating mitotic progression and paclitaxel cytotoxicity in PDAC cells. Mechanistically, our findings also suggest that MARK2 controls paclitaxel chemosensitivity by regulating class IIa HDACs. MARK2 directly phosphorylates HDAC4 specifically during antitubulin treatment. Phosphorylated HDAC4 promotes YAP activation and controls expression of YAP target genes induced by paclitaxel. Importantly, combination of HDAC inhibition and paclitaxel overcomes chemoresistance in organoid culture and preclinical PDAC animal models. The expression levels of MARK2, HDACs, and YAP are upregulated and positively correlated in PDAC patients. Inhibition of MARK2 or class IIa HDACs potentiates paclitaxel cytotoxicity by inducing mitotic abnormalities in PDAC cells. Together, our findings identify the MARK2-HDAC axis as a druggable target for overcoming chemoresistance in PDAC.
Topics: Animals; Cell Line, Tumor; Histone Deacetylases; Mitosis; Paclitaxel; Pancreatic Neoplasms
PubMed: 35780183
DOI: 10.1038/s41388-022-02399-3 -
EuroIntervention : Journal of EuroPCR... Apr 2020Drug-coated balloons (DCB) may avoid stent-associated long-term complications. This trial compared the clinical outcomes of patients with non-ST-elevation myocardial... (Randomized Controlled Trial)
Randomized Controlled Trial
AIMS
Drug-coated balloons (DCB) may avoid stent-associated long-term complications. This trial compared the clinical outcomes of patients with non-ST-elevation myocardial infarction (NSTEMI) treated with either DCB or stents.
METHODS AND RESULTS
A total of 210 patients with NSTEMI were enrolled in a randomised, controlled, non-inferiority multicentre trial comparing a paclitaxel iopromide-coated DCB with primary stent treatment. The main inclusion criterion was an identifiable culprit lesion without angiographic evidence of large thrombus. The primary endpoint was target lesion failure (TLF; combined clinical endpoint consisting of cardiac or unknown death, reinfarction, and target lesion revascularisation) after nine months. Secondary endpoints included total major adverse cardiovascular events (MACE) and individual clinical endpoints. Mean age was 67±12 years, 67% were male, 62% had multivessel disease, and 31% were diabetics. One hundred and four patients were randomised to DCB, 106 to stent treatment. In the stent group, 56% of patients were treated with BMS, 44% with current-generation DES. In the DCB group, 85% of patients were treated with DCB only whereas 15% underwent additional stent implantation. During a follow-up of 9.2±0.7 months, DCB treatment was non-inferior to stent treatment with a TLF rate of 3.8% versus 6.6% (intention-to-treat, p=0.53). There was no significant difference between BMS and current-generation DES. The total MACE rate was 6.7% for DCB versus 14.2% for stent treatment (p=0.11), and 5.9% versus 14.4% in the per protocol analysis (p=0.056), respectively.
CONCLUSIONS
In patients with NSTEMI, treatment of coronary de novo lesions with DCB was non-inferior to stenting with BMS or DES. These data warrant further investigation of DCB in this setting, in larger trials with DES as comparator (ClinicalTrials.gov Identifier: NCT01489449).
Topics: Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Restenosis; Coronary Vessels; Drug-Eluting Stents; Female; Humans; Male; Metals; Middle Aged; Non-ST Elevated Myocardial Infarction; Paclitaxel; Prosthesis Design; Sirolimus; Stents; Treatment Outcome; Ultrasonography, Interventional
PubMed: 31659986
DOI: 10.4244/EIJ-D-19-00723