Tumor Growth Inhibition Rate Research Articles

Mitochondria‐Targeted Photoredox Catalysis Activates Pyroptosis for Effective Tumor Therapy

AbstractThe development of biocompatible and efficient photocatalytic redox systems to mimic bio‐photoreactors in living cells holds great potential for manipulating intracellular biochemical reaction processes and thus advancing tumor therapy. In this study, a mitochondria‐targeted photoredox catalyst, 2D vacancy‐rich molybdenum oxide nanosheets (Mt‐VR‐MoO3) is presented. These nanosheets possess a high density of oxygen vacancies (19.2%) and exhibit strong photocatalytic redox activity under near‐infrared (NIR) light. Following a two‐step functionalization, Mt‐VR‐MoO3 effectively disrupts mitochondrial electron flow in an oxygen‐independent manner upon irradiation with second near‐infrared (NIR‐II) light. This targeted disruption leads to on‐demand induction of substantial damage to tumor cell mitochondria, characterized by increased production of mitochondrial reactive oxygen species (mtROS) and the release of cytochrome c (Cyt c), which collectively trigger the pyroptosis of cancer cells. The approach achieved tumor‐targeted photocatalytic eradication with high efficacy (tumor growth inhibition rate of 86.9%) in an orthotopic breast 4T1 murine tumor model, with no observable harm to normal organs. These findings provide inspiration for manipulating intracellular biochemical reactions using artificial photocatalytic materials, paving the way for pyroptosis activation as a promising approach in tumor therapy.

Discovery of 4-(4-(3-(1-(2-(piperidin-1-yl)ethyl)-1H-benzo[d]imidazole-2-yl)isoxazol-5-yl)phenyl)morpholine as a novel c-Myc inhibitor against lung cancer in vitro and in vivo

The critical role of c-Myc as a driving factor in the development and progression of lung cancer establishes it as a pivotal target for anti-lung cancer therapeutic research. In our previous study, we reported on the discovery of D347–2761, a novel small-molecule inhibitor that specifically targets the unstable domain of c-Myc and disrupts the c-Myc/Max heterodimer. To enhance targeted therapies further, we conducted an extensive structural analysis and designed a series of innovative benzimidazole derivatives. The cytotoxic activities of these compounds were assessed using the CCK-8 assay, revealing that compound A1 displayed IC50 values of 6.32 μM and 11.39 μM against the A549 and NCI–H1299 lung cancer cell lines, respectively, while compound A5 exhibited IC50 values of 4.08 μM and 7.86 μM against the same cell lines. Our findings revealed that compounds A1 and A5 exhibited potent anticancer activity by disrupting the interaction between c-Myc and Max proteins, leading to the downregulation of c-Myc protein levels and induction of apoptosis through apoptotic pathways. Notably, compound A5 demonstrated superior inhibitory capacity compared to other compounds tested. Furthermore, in a syngeneic tumor model, compound A5 exhibited excellent efficacy with a tumor growth inhibition rate reaching up to 76.4 %, accompanied by a significant reduction in c-Myc protein expression levels. Therefore, compound A5 holds promise as a potential agent for targeting c-Myc in anti-lung cancer therapy.

Design, synthesis, and in vitro and in vivo biological evaluation of dihydroartemisinin derivatives as potent anti-cancer agents with ferroptosis-inducing and apoptosis-activating properties

Natural products play a pivotal role in drug development, including their direct use as pharmaceuticals and their structural modification, yielding molecules with enhanced therapeutic potential. The discovery of bioactive molecules, lead compounds, and novel drugs is intrinsically linked to the structural optimization of natural products. In this study, forty-one derivatives of dihydroartemisinin (DHA) were synthesized by incorporating fragments with anti-tumour activity via molecular hybridization, and assessed for their anti-proliferative activity against human cancer cell lines (A549, Bel-7402, HCT-116, and SW620) and normal human liver cells (LO2). Most derivatives exhibited superior anti-proliferative activity compared to DHA. Notably, compound A3, featuring a 4-Cl phenyl carbamate moiety, demonstrated significant anti-proliferative activity against HCT-116 cells with an IC50 of 0.31 μM, making it 16-fold more potent than DHA (IC50 = 5.10 μM). The anti-proliferative mechanism did not involve cytotoxicity (SI = 54.13), indicating its superior safety profile compared to DHA (SI = 1.65).Further mechanistic studies revealed that compound A3 inhibits HCT-116 cell proliferation by modulating the expression of PI3K/AKT/mTOR and STAT3 proteins. STAT3 downregulation represses the expression of the critical ferroptosis protein glutathione peroxidase 4 (GPX4), aggravating the accumulation of reactive oxygen species (ROS) and depletion of glutathione (GSH). This redox imbalance triggers and accelerates ferroptosis. Additionally, A3 also induces apoptosis by damaging mitochondria and influencing MAPK signaling. Compound A3 arrested cells in the G2/M phase by regulating p53 expression. In an HCT-116 xenograft mouse model, compound A3 exhibited significant anti-cancer efficacy, with a tumor growth inhibition rate of 58.7 %. Therefore, compound A3 thus has the potential to serve as a lead compound for the development of new anti-tumor drugs.

Mobilizing STING Pathway via a Cationic Liposome to Enhance Doxorubicin‐Induced Antitumor Immunity

AbstractThe efficacy of anthracycline, such as doxorubicin (DOX), is facilitated by cancer cell‐intrinsic type I interferon (IFN‐I) signaling through the induction of immune responses. However, weak and chronic IFN‐I responses from rounds of chemotherapy lead to resistance against DNA damage and acquired resistance to the therapy. An exogenous supply of IFN‐I can improve the chemotherapeutic responses. Herein, a library of cationic liposomes is developed for the optimization of 1, 2‐dioleoyl‐3‐trimethylammonium‐propane (DOTAP) proportions to enhance the lysosome escape and tumor distribution of the stimulator of interferon genes (STING) agonist 2′,3′‐cyclic guanosine monophosphate‐adenosine monophosphate (cGAMP) and DOX. The cationic liposomes with 8% DOTAP release cGAMP into the cytoplasm and increase the concentration of DOX in the tumor by 1.5 times compared with the free drug. Upon accumulation at the tumor site, the optimized liposomes induce immunogenic cell death (ICD) and stimulate the STING signaling, thereby improving the production of endogenous IFN‐I and promoting dendritic cell maturation to mobilize T cell immunity. The tumor growth inhibition rate is 86%, and the median survival time is 1.6‐fold prolonged. This study offers a strategy to enhance the DOX‐induced immune response by activating the STING pathway to supply IFN‐I.

Discovery of Imidazo[1,2-a]pyrazine Derivatives as Potent ENPP1 Inhibitors.

ENPP1 acts as a negative regulator of the cGAS-STING pathway through the hydrolysis of 2'3'-cGAMP. Inhibitors of ENPP1 are regarded as promising agents for stimulating the immune response in cancer immunotherapy. This study describes the identification and optimization of imidazo[1,2-a]pyrazine derivative 7 as a highly potent and selective ENPP1 inhibitor. Compound 7 demonstrated substantial inhibitory activity against ENPP1 with an IC50 value of 5.70 or 9.68 nM while showing weak inhibition against ENPP2 and ENPP3. Furthermore, compound 7 was shown to enhance the mRNA expression of cGAMP-induced STING pathway downstream target genes, such as IFNB1, CXCL10, and IL6. In vivo pharmacokinetic and antitumor studies showed promising results, with 7 not only exhibiting efficient pharmacokinetic properties but also enhancing the antitumor efficacy of the anti-PD-1 antibody. Treatment with 7 (80 mg/kg) combined with anti-PD-1 antibody achieved a tumor growth inhibition rate of 77.7% and improved survival in a murine model.

Triple-targeted therapy of dabrafenib, trametinib, and osimertinib for the treatment of the acquired BRAF V600E mutation after progression on EGFR-tyrosine kinase inhibitors in advanced EGFR-mutated non-small cell lung cancer patients.

The B-Raf proto-oncogene, serine/threonine kinase (BRAF) V600E mutation is responsible for approximately 3% of acquired resistance mechanisms to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) in advanced EGFR-mutant non-small cell lung cancer (NSCLC). This study investigated the efficacy and safety of a triple-targeted therapy combining EGFR/BRAF/mitogen-activated protein kinase kinase (MEK) inhibitors of dabrafenib, trametinib, and osimertinib in NSCLC patients with acquired BRAF V600E mutation after EGFR-TKI treatment. A multi-center retrospective review of medical records was performed to analyze EGFR-mutated advanced Chinese NSCLC patients who acquired the BRAF V600E mutation following EGFR-TKI treatment. All patients subsequently received dabrafenib, trametinib, and osimertinib. The clinical characteristics, progression-free survival (PFS), and adverse events (AEs) were documented. The in-vivo drug response of patient-derived organoids (PDOs) was observed. Next-generation sequencing (NGS) was performed upon progression to triple-targeted therapy. Thirteen patients with BRAF V600E mutations were included. Following triple-targeted therapy, the corresponding objective response rate and disease control rate were 61.5% and 92.3%, respectively. The median PFS was 13.5 months (95% confidence interval: 6.6-20.4). PDOs derived from one patient's tumor sample were established, revealing that the triple-targeted therapy had a significantly lower half-maximal inhibitory concentration (IC50) value compared to other regimens. The tumor growth inhibitory rate was 99.36% for dabrafenib, trametinib, and osimertinib; 99.25% for osimertinib plus vemurafenib; 98.92% for osimertinib, encorafenib, and cetuximab; and 62.83% for pemetrexed plus carboplatin. NGS analysis identified major resistance mechanisms following the triple-targeted therapy, including the EGFR-dependent pathway, EGFR and BRAF V600E-dependent pathway, and an off-target mechanism. EGFR/BRAF/MEK triple-targeted therapy is an effective and safe approach for treating EGFR-mutated NSCLC patients resistant to EGFR-TKIs with acquired BRAF V600E mutations.

Targeting CD47 and Angiogenesis Demonstrates Effective Anti-Tumor Effect in Bladder Cancer.

Background: Although immunotherapy has shown potential in cancer treatment, current immunotherapeutics for bladder cancer are limited by a low response rate. Therefore, it is necessary to investigate other suitable immunotherapeutic targets and strategies for bladder cancer. Methods: To evaluate whether CD47 could be a suitable target for bladder cancer immunotherapy, CD47 protein expression levels in 116 bladder cancer tissue samples were assessed by IHC staining. In vitro anti-tumor effect of blocking CD47 was examined by phagocytosis assays. In vivo anti-tumor effects of targeting CD47 and angiogenesis were experimented in the HSPCs-CDX model. Results: We find that CD47 is highly expressed in bladder cancer samples and is associated with poor prognosis. Blocking CD47 could enhance the human PBMC-derived macrophages' phagocytosis of T24 (from 10.40% to 29.70%) and 5637 (from 5.31% to 33.52%) human bladder cancer cells, as well as demonstrate anti-tumor effects in the HSPCs-CDX model (tumor growth inhibition rate, TGI: 33.05%). During CD47 treatment, we observed that the level of angiogenesis increased after CD47 blockade, and it might undermine the effect of CD47 immunotherapy. We then combined CD47 blockade with anti-angiogenic drugs to treat bladder cancer and discovered that inhibiting angiogenesis could further improve the anti-tumor effect of CD47 blockade (TGI: 76.39%). Finally, we tested the anti-tumor effect of co-targeting CD47 and angiogenesis using a bispecific fusion protein, SIRPα-VEGFR1, which successfully inhibited tumor growth to a similar extent as a combination therapy. Conclusions: Our study suggests that targeting CD47 could inhibit the growth of bladder cancer by promoting macrophage-mediated anti-tumor immunity. Moreover, blocking CD47 and angiogenesis could achieve a potent anti-tumor effect and could be an effective immunotherapy strategy for bladder cancer.

X-ray triggered scintillator versatile nanocatalytic platform for synergistic photodynamic/chemodynamic therapy

Nanocatalysts with photodynamic therapy (PDT) and chemodynamic therapy (CDT) are excellent for tumor therapy. However, it is still challenging to achieve complete tumor eradication due to the drawbacks of limited penetration depth of intratumoural tissues, hypoxia and complexity of the tumor microenvironment (TME). Herein, we fabricated an integrated multifunctional nanoreactor (LuAG:Tb/Ce-RB@ZIF-8-Au2Pt-HA, LRZAPH) combining scintillating nanoparticles (SCNPs, LuAG:Tb/Ce), a metal-organic framework (ZIF-8), and bimetallic Au2Pt for X-ray-triggered PDT and dual noble-metal nanozyme catalyzed CDT. Such a nanoreactor not only significantly enhanced the PDT effect under X-ray irradiation through full resonance energy transfer from LuAG:Tb/Ce scintillator to Ross Bengal (RB), but also facilitated the reactive oxygen species (ROS) and oxygen (O2) production through the excellent peroxidase-like (POD-like) and catalase-like (CAT-like) catalytic properties of Au2Pt nanozymes. O2 also alleviates hypoxia in intratumoural tissues during coordinated PDT. In addition, the dissociation behavior of ZIF-8 with pH-responsive and targeted of hyaluronic acid (HA) in acidic TME significantly enhanced the therapeutic efficacy of LRZAPH nanocatalysts. Significantly, the high tumor growth inhibition rate of 93 % was revealed due to radiotherapy (RT)/PDT/CDT synergetic therapy in vivo, which minimized the toxic and side effects of conventional clinical radiotherapy/chemotherapy on human. The synergistic effect of LRZAPH nanocatalysts on PDT and catalytically induced CDT is expected to provide new pathways for effective treatment of deep tumors.

Expression of cancer susceptibility candidate 11 in ovarian cancer tissues and its role in doxorubicin resistance.

We aimed to investigate the expression of cancer susceptibility candidate 11 (CASC11) in ovarian cancer (OC) tissues and its role in doxorubicin (Dox) resistance. A total of 98 patients were included as subjects. Reverse transcription-polymerase chain reaction was employed to determine the expressions of CASC11 in OC and para-OC tissues, and in OC cells (A2780, SKOV3, OVCAR3 and A547) and human normal ovarian epithelial cells (IOSE-80) from these patients. OC SKOV3/R cell line with Dox resistance was established and transfected with small interfering (si)-CASC11 to down-regulate CASC11 expression. Based on the constructed nude mouse model of orthotopic transplanted tumor, the growth curves were plotted, and the changes in tumor volume and apoptosis were observed by hematoxylin-eosin staining. OC tissues had a significantly higher mRNA expression of CASC11 than that of para-OC tissues (P < 0.05). A547, OVCAR3, A2780 and SKOV3 cells had significantly higher mRNA expressions of CASC11 than that of IOSE-80 cells (P < 0.05). The transplanted tumor was significantly smaller in volume in the si-CASC11 group than that in the si-normal control (NC) group from the 8th days after transplanted tumor inoculation (P < 0.05). The tumor growth inhibition rate significantly rose in the si-CASC11 group in comparison with that in the si-NC group (P < 0.05). CASC11 has high expression in OC tissues. Knockout of CASC11 weakens the proliferative, invasive and migratory potentials and enhances the apoptotic potential of Dox-resistant OC cells, thereby reversing their Dox resistance.

Cu0-based nanoparticles boost anti-tumor efficacy via synergy of cuproptosis and ferroptosis enhanced by cuproptosis-induced glutathione synthesis disorder

Apoptotic resistance of tumor often leads to poor efficacy from mono-therapy based on apoptosis. Cuproptosis, a new type of non-apoptotic cell death related to mitochondrial dysfunction, can alter metabolism and enhance ferroptosis, providing a promising strategy for effective synergistic cancer treatment. In this work, Cu0-based nanoparticles (denoted as HA-ZCu) were successfully developed to improve anti-tumor efficacy by combining cuproptosis with enhanced ferroptosis, which was achieved by cuproptosis-induced glutathione synthesis disorder. In vitro studies revealed that HA-ZCu effectively induced cuproptosis and ferroptosis in HepG2 cells. Moreover, HA-ZCu induced mitochondrial dysfunction and decreased intracellular adenosine triphosphate (ATP), glutamate, and glutathione, demonstrating the effective synergy. In vivo studies further approved the synergistic therapeutic efficacy of HA-ZCu, where the inhibition rate of tumor growth reached 83.2 %. This work represents the first example of enhanced anti-tumor efficacy via cuproptosis and ferroptosis synergy through cuproptosis-induced glutathione synthesis disorder.

Effects of low-frequency ultrasound combined with microbubbles on breast cancer xenografts in nude mice.

The aim of this study was to explore the effects of low-frequency ultrasound (US) combined with microbubbles (MBs) on breast cancer xenografts and explain its underlying mechanisms. A total of 20 xenografted nude mice were randomly divided into four groups: a group treated with US plus MBs (the US + MBs group), a group treated with US alone (the US group), a group treated with MBs alone (the MBs group), and a control group. In different groups, mice were treated with different US and injection regimens on an alternate day, three times in total. Histological changes, apoptosis of cells, microvascular changes, and the apoptosis index (AI) and microvascular density (MVD) of the breast cancer xenograft were analyzed after the mice were sacrificed. Results indicated that the tumor volume in the US + MBs group was smaller than that in the other three groups (p < 0.001 for all). The rate of tumor growth inhibition in the US + MBs group was significantly higher than that in the US and MBs groups (p < 0.001 for both). There were no significant differences in histological changes among the four groups. However, the AI was higher in the US + MBs group than that in the other three groups while the MVD was lower (p < 0.001 for all). All in all, low-frequency US combined with MBs can effectively slow down the growth of breast cancer in nude mice. In summary, low-frequency US combined with MBs has a significant effect on breast cancer treatment. Cavitation, thermal effects, and mechanical effects all play a vital role in the inhibition of tumor growth.

Adaptive Size Evolution of an MOFs-in-MOF Nanovehicle for Enhanced Nucleus-Targeted Tumor Chemotherapy.

A metal-organic frameworks (MOFs)-in-MOF nanovehicle (160 nm), which was constructed with newly prepared ultrasmall Cu(I)Cu(II)-BTC MOFs (UCMs, 2.95 nm) loaded with doxorubicin (DOX) and a nuclear localization signal (NLS) peptide as multicores (UCMDNs) and ZIF-8 as the shell MOF, was proposed to cross layers of biological barriers with adaptive size evolution capacity for achieving efficient nucleus-targeted drug delivery. It first enhanced tumor tissue penetration through its larger nanosize effect. Then the acidic tumor environment made the ZIF-8 shell degrade, releasing small-sized UCMDNs to enter into the cell and into the nucleus under the guidance of NLS. Furthermore, due to the distinct surface structural characteristics of UCMs, UCMDNs remained stable in the cytoplasm and collapsed in the nucleus due to the DOX-DNA interaction to deliver DOX precisely. It showed superior performance in the nucleus-directed delivery of DOX (delivery efficiency up to 56.7%) and a high tumor growth inhibition rate (96.4%), offering promising prospects in tumor chemotherapy.

Light-Responsive conjugated polymer nanoparticles with Spatial-Controlled camptothecin release via π − π stacking for improved Combinatorial therapy of breast cancer

The treatment of breast cancer (BC) remains a significant challenge, exemplified by the limitations of chemotherapy due to its high side effects. Light-responsive drug delivery systems (DDS) offer a promising approach to spatially and temporally release drugs, minimizing chemotherapy side effects and enhancing efficacy. However, achieving precise delivery and site-specific drug release poses complex challenges. Here, We present a novel nano-system combining light-responsive photothermal therapy (PTT) with photothermal-responsive chemotherapy via π − π Stacking. Conjugated polymer nanoparticles (cRGD-PTer N25/CPT NPs) is designed for spatiotemporal targeted PTT/chemotherapy. Research shows that the strong near-infrared absorption of PTer N25 endows cRGD-PTer N25/CPT NPs with excellent photothermal capabilities(57.4 %) and near-infrared laser-triggered drug release performance. The cRGD-PTer N25/CPT NPs enhanced BC-specific cellular accumulation, prolonged blood circulation, exhibited good biocompatibility, and improved PTT and chemotherapy efficacy in BC cell lines and mouse models while reducing systemic toxicity. The photothermal effect triggered the on-demand release of camptothecin (CPT), producing therapeutic effects and downregulating heat shock protein 70 (HSP 70), reducing cancer cell thermoresistance, and enhancing combined treatment efficacy. Under spatial and temporal control, the tumor growth inhibition rate of the cRGD-PTer N25/CPT NPs group reached 93.6 %, nearly eradicating tumor presence, whereas the control group exhibited only partial inhibition. Minimal cardiotoxicity and metastatic side effects are not observed. This work presents a viable strategy for designing novel controlled-release drug systems to improve breast cancer treatment efficiency.

Efficient delivery of curcumin by functional solid lipid nanoparticles with promoting endosomal escape and liver targeting properties

In the realm of intracellular drug delivery, overcoming the barrier of endosomal entrapment stands as a critical factor influencing the effectiveness of nanodrug delivery systems. This study focuses on the synthesis of an acid-sensitive fatty acid derivative called imidazole-stearic acid (IM-SA). Leveraging the proton sponge effect attributed to imidazole groups, IM-SA was anticipated to play a pivotal role in facilitating endosomal escape. Integrated into the lipid core of solid lipid nanoparticles (SLNs), IM-SA was paired with hyaluronic acid (HA) coating on the surface of SLNs loading with curcumin (CUR). The presence of IM-SA and HA endowed HA-IM-SLNs@CUR with dual functionalities, enabling the promotion of endosomal escape, and specifical targeting of liver cancer. HA-IM-SLNs@CUR exhibited a particle size of ∼228 nm, with impressive encapsulation efficiencies (EE) of 87.5 % ± 2.3 % for CUR. Drugs exhibit significant pH sensitive release behavior. Cellular experiments showed that HA-IM-SLN@CUR exhibits enhanced drug delivery capability. The incorporation of IM-SA significantly improved the endosomal escape of HA-IM-SLN@CUR, facilitating accelerated intracellular drug release and increasing intracellular drug concentration, exhibiting excellent growth inhibitory effects on HepG2 cells. Animal experiments revealed a 3.4-fold increase in CUR uptake at the tumor site with HA-IM-SLNs@CUR over the free CUR, demonstrating remarkable tumor homing potential with the tumor growth inhibition rate of 97.2 %. These findings indicated the significant promise of HA-IM-SLNs@CUR in the realm of cancer drug delivery.

Resveratrol liposomes reverse sorafenib resistance in renal cell carcinoma models by modulating PI3K-AKT-mTOR and VHL-HIF signaling pathways

RCC is a malignant tumor arising from the urothelium of renal parenchyma that remains challenging to be treated. In this study, we assessed the anti-tumor effects of Resveratrol liposomes (RES-lips) combined with sorafenib on renal cell carcinoma (RCC) and explored the potential mechanisms underlying the improvement of sorafenib resistance models. Tumor growth and survival following treatment with sorafenib alone or in combination with RES-lips was evaluated in a RCC xenograft mouse model. Flow cytometry results demonstrated that the combination of RES-lips and sorafenib significantly enhanced the G1/S phase arrest of sorafenib-resistant cells. When compared with the PBS or monotherapy groups, treatment with RES-lips combined with sorafenib exhibited significant inhibition of tumor growth in the RCC xenograft mouse model with tumor growth inhibition (TGI) rates and complete remission (CR) rates of 90.1 % and 50 %, respectively. Concersely, the maximum TGI rate was 53.6 % in the RES-lips monoherapy group and 29.2 % and in the sorafenib monotherapy group, and no animals achieved CR. Additionally, the current combination therapy promoted the proliferation of unactivated splenic lymphocytes and the proliferation of soybean protein A- and lipopolysaccharide-stimulated lymphocytes compared with PBS or monotherapy treatments. Further western blotting analysis suggested that RES-lips may enhance the resistance of RCC to sorafenib by inhibiting PI3K-AKT-mTOR and VHL-HIF signaling pathways, ultimately augmenting the tumor growth inhibition effect of the combination therapy. RES-lips may improve the sorafenib resistance in RCC, and the underlying mechanism may be related to the regulation of PI3K-AKT-mTOR and VHL-HIF signaling pathways.

Identification of 6-Fluorine-Substituted Coumarin Analogues as POLRMT Inhibitors with High Potency and Safety for Treatment of Pancreatic Cancer.

Increasing evidence has demonstrated that oxidative phosphorylation (OXPHOS) is closely associated with the progression of pancreatic cancer (PC). Given its central role in mitochondrial transcription, the human mitochondrial RNA polymerase (POLRMT) is a promising target for developing PC treatments. Herein, structure-activity relationship exploration led to the identification of compound S7, which was the first reported POLRMT inhibitor possessing single-digit nanomolar potency of inhibiting PC cells proliferation. Mechanistic studies showed that compound S7 exerted antiproliferative effects without affecting the cell cycle, apoptosis, mitochondrial membrane potential (MMP), or intracellular reactive oxygen species (ROS) levels specifically in MIA PaCa-2 cells. Notably, compound S7 inhibited tumor growth in MIA PaCa-2 xenograft tumor model with a tumor growth inhibition (TGI) rate of 64.52% demonstrating significant improvement compared to the positive control (44.80%). In conclusion, this work enriched SARs of POLRMT inhibitors, and compound S7 deserved further investigations of drug-likeness as a candidate for PC treatment.

Cancer cell membrane-camouflaged paclitaxel/PLGA nanoparticles for targeted therapy against lung cancer

Paclitaxel (PTX) is a first-line drug for the treatment of lung cancer, but its targeting and therapeutic effect are unsatisfactory. Herein, lung cancer cell (A549) membrane biomimetic PTX-loaded poly (lactic-co-glycolic acid) (PLGA) nanoparticles (AM@PTX-NPs) were constructed to eliminate the shortcomings of PTX. The AM@PTX-NPs were successfully prepared with a high drug loading efficiency (10.90±0.06 %). Moreover, transmission electron microscopy, SDS-PAGE, and western blotting proved that AM@PTX-NPs were spherical nanoparticles camouflaged by the A549 cell membrane. Both in vitro and in vivo assays revealed that the AM@PTX-NPs displayed outstanding targeting capacity due to A549 membrane modification. The cytotoxicity experiment showed that the developed biomimetic formulation was able to effectively reduce the proliferation of A549 cells. Moreover, AM@PTX-NPs exhibited a significant tumor growth inhibition rate (73.00 %) with good safety in the tumor-bearing mice, which was higher than that of the PTX-NPs without A549 membrane coating (37.39 %). Overall, the constructed bioinspired vector could provide a novel platform for the PTX delivery and demonstrated a promising strategy for the targeted cancer treatment.

Mitochondrial-targeted cyclometalated Ir(III)-5,7-dibromo/dichloro-2-methyl-8-hydroxyquinoline complexes and their anticancer efficacy evaluation in Hep-G2 cells.

Both 8-hydroxyquinoline compounds and iridium (Ir) complexes have emerged as potential novel agents for tumor therapy. In this study, we synthesized and characterized two new Ir(III) complexes, [Ir(L1)(bppy)2] (Br-Ir) and [Ir(L2)(bppy)2] (Cl-Ir), with 5,7-dibromo-2-methyl-8-hydroxyquinoline (HL-1) or 5,7-dichloro-2-methyl-8-hydroxyquinoline as the primary ligand. Complexes Br-Ir and Cl-Ir successfully inhibited antitumor activity in Hep-G2 cells. In addition, complexes Br-Ir and Cl-Ir were localized in the mitochondrial membrane and caused mitochondrial damage, autophagy, and cellular immunity in Hep-G2 cells. We tested the proteins related to mitochondrial and mitophagy by western blot analysis, which showed that they triggered mitophagy-mediated apoptotic cell death. Remarkably, complex Br-Ir showed high in vivo antitumor activity, and the tumor growth inhibition rate was 63.0% (P<0.05). In summary, our study on complex Br-Ir revealed promising results in in vitro and in vivo antitumor activity assays.

The circadian clock gene BMAL1 increases radiosensitivity in nasopharyngeal carcinoma cell CNE2

ObjectiveTo investigate the involvement of the circadian clock gene BMAL1 in regulating radiosensitivity in nasopharyngeal carcinoma (NPC). MethodsThe regulatory role of BMAL1 in NPC radiotherapy was investigated using 44 NPC cases and the NPC cell line CNE2, which had been genetically modified to either overexpress or silence BMAL1. Infected CNE2 cells were divided into four groups, including those with BMAL1 overexpression and BMAL1 RNA interference (RNAi), as well as their respective control groups. The group responses to different doses of radiotherapy were examined. ResultsThe 5-year survival rates of the BMAL1 overexpression group demonstrated a significant increase compared to those of the low expression group (p < 0.05). Furthermore, the BMAL1 overexpression group exhibited a higher tumor-growth inhibition rate (p < 0.001) and apoptotic rate (p = 0.004) following radiotherapy; a decreased proportion of S-phase cells (p < 0.001) but an increased proportion of G2/M-phase cells (p = 0.001) after 24 h of 8Gy irradiation; reduced number of cell colonies (p = 0.042), and a lower survival score (p = 0.037). ConclusionsOur findings demonstrate a positive correlation between BMAL1 expression and NPC survival, suggesting that BMAL1 promotes NPC radiosensitivity.

Novel Pt(IV) complexes containing salvigenin ligand reverse cisplatin-induced resistance by inhibiting Rap1b-mediated cancer cell stemness in esophageal squamous cell carcinoma treatments

Esophageal squamous cell carcinoma (ESCC) is a malignant tumor that is highly susceptible to metastasis, recurrence and resistance, and few therapeutic targets have been identified and proven effective. Herein, we demonstrated for the first time that Rap1b can positively regulate ESCC cell stemness, as well as designed and synthesized a novel class of Pt(IV) complexes that can effectively inhibit Raplb. In vitro biological studies showed that complex-1 exhibited stronger cytotoxicity than cisplatin and oxaliplatin against a variety of ESCC cells, and effectively reversed cisplatin-induced resistance of TE6 cells by increasing cellular accumulation of platinum and inhibiting cancer cell stemness. Significantly, complex-1 also exhibited strong ability to reversal cisplatin-induced cancer cell resistance and inhibit tumor growth in TE6/cDDP xenograft mice models, with a tumor growth inhibition rate of 73.3 % at 13 mg/kg and did not show significant systemic toxicity. Overall, Rap1b is a promising target to be developed as an effective treatment for ESCC. Complex-1, as the first Pt(IV) complex that can strongly inhibit Rap1b, is also worthy of further in-depth study.