Cell-bearing Mice Research Articles

Phenethyl Isothiocyanate-Conjugated Chitosan Oligosaccharide Nanophotosensitizers for Photodynamic Treatment of Human Cancer Cells.

The aim of this study is to synthesize phenethyl-conjugated chitosan oligosaccharide (COS) (abbreviated as ChitoPEITC) conjugates and then fabricate chlorin E6 (Ce6)-incorporated nanophotosensitizers for photodynamic therapy (PDT) of HCT-116 colon carcinoma cells. PEITC was conjugated with the amine group of COS. Ce6-incorporated nanophotosensitizers using ChitoPEITC (ChitoPEITC nanophotosensitizers) were fabricated by dialysis method. 1H nuclear magnetic resonance (NMR) spectra showed that specific peaks of COS and PEITC were observed at ChitoPEITC conjugates. Transmission electron microscope (TEM) confirmed that ChitoPEITC nanophotosensitizers have spherical shapes with small hydrodynamic diameters less than 200 nm. The higher PEITC contents in the ChitoPEITC copolymer resulted in a slower release rate of Ce6 from nanophotosensitizers. Furthermore, the higher Ce6 contents resulted in a slower release rate of Ce6. In cell culture study, ChitoPEITC nanophotosensitizers showed low toxicity against normal CCD986Sk human skin fibroblast cells and HCT-116 human colon carcinoma cells in the absence of light irradiation. ChitoPEITC nanophotosensitizers showed a significantly higher Ce6 uptake ratio than that of free Ce6. Under light irradiation, cellular reactive oxygen species (ROS) production of nanophotosensitizers was significantly higher than that of free Ce6. Especially, PEITC and/or ChitoPEITC themselves contributed to the production of cellular ROS regardless of light irradiation. ChitoPEITC nanophotosensitizers showed significantly higher PDT efficacy against HCT-116 cells than that of free Ce6. These results indicate that ChitoPEITC nanophotosensitizers have superior potential in Ce6 uptake, ROS production and PDT efficacy. In the HCT-116 cell-bearing mice tumor-xenograft model, ChitoPEITC nanophotosensitizers efficiently inhibited growth of tumor volume rather than free Ce6. In the animal imaging study, ChitoPEITC nanophotosensitizers were concentrated in the tumor tissue, i.e., fluorescence intensity in the tumor tissue was stronger than that of other tissues. We suggest that ChitoPEITC nanophotosensitizers are a promising candidate for the treatment of human colon cancer cells.

Assessment of Antioxidant and Antineoplastic Activities Blumea Lacera (burn. F) Leaves

Blumea lacera (Burn. f.) DC. (Family: Asteraceae) is an important member of Bangladeshi natural plant resource and it is an herbaceous weed locally known as Kukursunga. Different parts of this plant are used traditionally to cure various diseases. But detail study on the antioxidant and antineoplastic potentials of Blumea lacera leaves, has not yet been done. Aim of this study is to examine the antioxidant and antineoplastic properties and quantify the different type of phytochemical content of the methanolic extract of leaves of Blumea lacera (MELB). MELB contained a rich polyphenol, flavonol, flavonoid and proanthocyanidins. MELB showed moderate cytotoxic effect against Artemia salina (brine shrimp nauplii) where its LD50 values was 66.12 µg/ml. In vitro antioxidant assay, MELB exhibited a remarkable capacity to scavenge the tested reactive species. MELB scavenged DPPH with an IC50 of 33.64 µg/mL and 42.69 µg/mL, respectively. In vivo antineoplastic assay, MELB significantly (P<0.05) decreased viable cell count and increased the survival time of EAC cell bearing mice. Hematological profiles were also restored significantly (P<0.05) to normal levels in MELB treated mice as compared to untreated EAC control mice. In addition, fluorescence microscopic view of EAC cells derived from MELB-treated group showed apoptotic characteristics in treated cells compared to untreated EAC control. our findings suggest that methanolic extract of Blumea lacera leaves(MELB) might be a potential agent with antioxidant properties for prevention of cancer and has the merit for further investigation in isolating its active constituents.

PFKFB4 facilitates palbociclib resistance in oestrogen receptor-positive breast cancer by enhancing stemness.

ER+ breast cancer (ER+ BC) is the most common subtype of BC. Recently, CDK4/6 inhibitors combined with aromatase inhibitors have been approved by FDA as the first-line therapy for patients with ER+ BC, and showed promising therapeutic efficacy in clinical treatment. However, resistance to CDK4/6 inhibitors is frequently observed. A better understanding of the drug resistance mechanism is beneficial to improving therapeutic strategies by identifying optimal combinational treatments. Western blotting, qPCR, flow cytometry and a series of cell experiments were performed to evaluate the phenotype of MCF-7/R cells. RNA sequencing, non-targeted metabolomics, shRNA knockdown and tumour cell-bearing mouse models were used to clarify the drug resistance mechanism. Here, we found that ER+ BC cells have shown an adaptive resistance to palbociclib-induced cell cycle arrest by activating an alternative signal pathway, independent of the CDK4/6-RB signal transduction. Continuing treatment of palbociclib evoked cellular senescence of ER+ BC cells. Subsequently, the senescence-like phenotype promoted stemness of ER+ BC cells, accompanied by increased chemoresistance and tumour-initiating potential. Based on transcriptome analysis, we found that PFKFB4 played an important role in stemness transformation and drug resistance. A close correlation was determined between PFKFB4 expression by ER+ BC cells and cell senescence and stemness. Mechanistically, metabolomic profiling revealed that PFKFB4 reprogramed glucose metabolism and promoted cell stemness by enhancing glycolysis. Strikingly, diminishing PFKFB4 levels improved drug sensitivity and overcame chemoresistance during palbociclib treatment in ER+ BC. These findings not only demonstrated the novel mechanism underlying which ER+ BC cells resisted to palbociclib, but also provided a possible therapeutic strategy in the intervention of ER+ BC to overcome drug resistance.

Flagellin synergistically enhances anti-tumor effect of EGFRvIII peptide in a glioblastoma-bearing mouse brain tumor model

BackgroundGlioblastoma (GBM) is the most aggressive type of brain tumor with heterogeneity and strong invasive ability. Treatment of GBM has not improved significantly despite the progress of immunotherapy and classical therapy. Epidermal growth factor receptor variant III (EGFRvIII), one of GBM-associated mutants, is regarded as an ideal therapeutic target in EGFRvIII-expressed GBM patients because it is a tumor-specific receptor expressed only in tumors. Flagellin B (FlaB) originated from Vibrio vulnificus, is known as a strong adjuvant that enhances innate and adaptive immunity in various vaccine models. This study investigated whether FlaB synergistically could enhance the anti-tumor effect of EGFRvIII peptide (PEGFRvIII).MethodsEGFRvIII-GL261/Fluc cells were used for glioblastoma-bearing mouse brain model. Cell-bearing mice were inoculated with PBS, FlaB alone, PEGFRvIII alone, and PEGFRvIII plus FlaB. Tumor growth based on MRI and the survival rate was investigated. T cell population was examined by flow cytometry analysis. Both cleaved caspase-3 and CD8 + lymphocytes were shown by immunohistochemistry (IHC) staining.ResultsThe PEGFRvIII plus FlaB group showed delayed tumor growth and increased survival rate when compared to other treatment groups. As evidence of apoptosis, cleaved caspase-3 expression and DNA disruption were more increased in the PEGFRvIII plus FlaB group than in other groups. In addition, the PEGFRvIII plus FlaB group showed more increased CD8 + T cells and decreased Treg cells than other treatment groups in the brain.ConclusionsFlaB can enhance the anti-tumor effect of PEGFRvIII by increasing CD8 + T cell response in a mouse brain GBM model.

Drug library screening identifies histone deacetylase inhibition as a novel therapeutic strategy for choriocarcinoma.

Choriocarcinoma is a rare and aggressive gynecological malignancy. The standard treatment is systemic chemotherapy as choriocarcinoma exhibits high chemosensitivity. However, refractory choriocarcinoma exhibits chemoresistance; thus, the prognosis remains very poor. This study aimed to identify novel therapeutic agents for choriocarcinoma by utilizing a drug repositioning strategy. Three choriocarcinoma cell lines (JAR, JEG-3, and BeWo) and a human extravillous trophoblast cell line (HTR-8/SVneo) were used for the analyses. The growth inhibitory effects of 1,271 FDA-approved compounds were evaluated in vitro screening assays and selected drugs were tested in tumor-bearing mice. Functional analyses of drug effects were performed based on RNA sequencing. Muti-step screening identified vorinostat, camptothecin (S, +), topotecan, proscillaridin A, and digoxin as exhibiting an anti-cancer effect in choriocarcinoma cells. Vorinostat, a histone deacetylase inhibitor, was selected as a promising candidate for validation and the IC50 values for choriocarcinoma cells were approximately 1 μM. RNA sequencing and subsequent pathway analysis revealed that the ferroptosis pathway was likely implicated, and key ferroptosis-related genes (i.e., GPX4, NRF2, and SLC3A2) were downregulated following vorinostat treatment. Furthermore, vorinostat repressed tumor growth and downregulated the expression of GPX4 and NRF2 in JAR cell-bearing mice model. Vorinostat, a clinically approved drug for the treatment of advanced primary cutaneous T-cell lymphoma, showed a remarkable anticancer effect both in vitro and in vivo by regulating the expression of ferroptosis-related genes. Therefore, vorinostat may be an effective therapeutic candidate for patients with choriocarcinoma.

ATM/IKK alpha axis regulates the crosstalk between autophagy and apoptosis in selenite-treated Jurkat cells

Selenium is an essential trace element. High dosage of selenite exhibits a great potential in treating leukemia. Previous study discovered selenite could promote leukemia cells apoptosis through inducing DNA damage and cell cycle arrest, while the switch mechanisms of these events and autophagy were still unclear. Current study discovered selenite promoted autophagy and apoptosis of leukemia Jurkat cells. In this process, DNA damage related ATM/IKK alpha axis was activated. This axis could stabilize pro-apoptotic P73, and promote autophagy through regulating NF-kappaB signaling pathway. Moreover, survivin-2B was also confirmed to be necessary for the ATM-induced nuclear location of IKK alpha, and therefore stood at the node position of apoptosis and autophagy cascades inside Jurkat cells. Finally, our in vivo experiments proved that selenite exhibited some anti-tumor effects on Jurkat cells-bearing mice. Moreover, alterations of ATM and IKK alpha expression observed in vivo were similar to that identified in vitro. Therefore, our findings had fully confirmed survivin-2B dependent activation of ATM/IKK alpha axis might be another crosstalk between autophagy and apoptosis of selenite-treated leukemia cells.

A Positron Emission Tomography Tracer Targeting the S2 Subunit of SARS-CoV-2 in Extrapulmonary Infections.

Tracking the pathogen of coronavirus disease 2019 (COVID-19) in live subjects may help estimate the spatiotemporal distribution of SARS-CoV-2 infection in vivo. This study developed a positron emission tomography (PET) tracer of the S2 subunit of spike (S) protein for imaging SARS-CoV-2. A pan-coronavirus inhibitor, EK1 peptide, was synthesized and radiolabeled with copper-64 after being conjugated with 1,4,7-triazacyclononane-1,4,7-triyl-triacetic acid (NOTA). The in vitro stability tests indicated that [64Cu]Cu-NOTA-EK1 was stable up to 24 h both in saline and in human serum. The binding assay showed that [64Cu]Cu-NOTA-EK1 has a nanomolar affinity (Ki = 3.94 ± 0.51 nM) with the S-protein of SARS-CoV-2. The cell uptake evaluation used HEK293T/S+ and HEK293T/S– cell lines that showed that the tracer has a high affinity with the S-protein on the cellular level. For the in vivo study, we tested [64Cu]Cu-NOTA-EK1 in HEK293T/S+ cell xenograft-bearing mice (n = 3) and pseudovirus of SARS-CoV-2-infected HEK293T/ACE2 cell bearing mice (n = 3). The best radioactive xenograft-to-muscle ratio (X/Nxenograft 8.04 ± 0.99, X/Npseudovirus 6.47 ± 0.71) was most evident 4 h postinjection. Finally, PET imaging in the surrogate mouse model of beta-coronavirus, mouse hepatic virus-A59 infection in C57BL/6 J mice showed significantly enhanced accumulation in the liver than in the uninfected mice (1.626 ± 0.136 vs 0.871 ± 0.086 %ID/g, n = 3, P < 0.05) at 4 h postinjection. In conclusion, our experimental results demonstrate that [64Cu]Cu-NOTA-EK1 is a potential molecular imaging probe for tracking SARS-CoV-2 in extrapulmonary infections in living subjects.

PEGylated Cisplatin Nanoparticles for Treating Colorectal Cancer in a pH-Responsive Manner

Colorectal cancer (CRC) is a common malignant tumor, and its incidence ranks third and mortality rate ranks second in the world. Cisplatin cannot target CRC cells and has notable toxicity, which significantly limits its clinical application. The emerging PEGylated nanodrug delivery system can improve circulation time and enhance tumor targeting. In this study, the HA-mPEG-Cis NPs were synthesized by self-assembly, which can target CD44-positive CRC cells and dissolve the PEG hydration layer responsive to the weakly acidic tumor environment. The average hydrodynamic diameter of HA-mPEG-Cis NPs was 48 nm with the polydispersity index of 0.13. The in vitro cisplatin release was in a pH-responsive manner. The HA-mPEG-Cis NPs group showed the highest apoptosis rate (25.1%). The HA-mPEG-Cis NPs exhibited antitumor efficacy via the PI3K/AKT/mTOR signaling pathway. The HA-mPEG-Cis NPs showed the lowest tumor volume and weight among all the groups in CT26 cell-bearing mouse model. The HA-mPEG-Cis nanodrug delivery system not only increases the stability and circulation time but also reduces the side effects of loaded cisplatin. Overall, the in vitro and in vivo experiments confirmed the satisfied antitumor efficacy of HA-mPEG-Cis NPs. Therefore, this study provides a rational design for application of pH-responsive HA-mPEG-Cis nanodrug delivery system in the future.

Live Macrophage-Delivered Doxorubicin-Loaded Liposomes Effectively Treat Triple-Negative Breast Cancer.

Triple-negative breast cancer is often aggressive and resistant to various cancer therapies, especially corresponding targeted drugs. It is shown that targeted delivery of chemotherapeutic drugs to tumor sites could enhance treatment outcome against triple-negative breast cancer. In this study, we exploited the active tumor-targeting capability of macrophages by loading doxorubicin-carrying liposomes on their surfaces via biotin-avidin interactions. Compared with conventional liposomes, this macrophage-liposome (MA-Lip) system further increased doxorubicin accumulation in tumor sites, penetrated deeper into tumor tissue, and enhanced antitumor immune response. As a result, the MA-Lip system significantly lengthened the survival rate of 4T1 cell-bearing mice with low toxicity. Besides, the MA-Lip system used highly biocompatible and widely approved materials, which ensured its long-term safety. This study provides a system for triple-negative breast cancer treatment and offers another macrophage-based strategy for tumor delivery.

Potential of Mycobacterium tuberculosis chorismate mutase (Rv1885c) as a novel TLR4-mediated adjuvant for dendritic cell-based cancer immunotherapy

ABSTRACT For clinical application by dendritic cell (DC)-based cancer immunotherapy, a proper adjuvant system to elicit a strong anticancer immune response is needed. Here, we investigated the potential of chorismate mutase (TBCM, Rv1885c), a putative Mycobacterium tuberculosis (TB) virulence factor, as an immunoadjuvant in DC-based tumor immunotherapy. First, we found that TBCM functionally activated DCs by upregulating costimulatory molecules, increasing the secretion of proinflammatory cytokines, enhancing migration and inducing the Th1-type immune response in a dose-dependent manner via TLR4-mediated signaling. In addition, subcutaneous injection of TBCM-activated DCs loaded with cell lysates led to reduced tumor mass, enhanced mouse survival and lowered tumor incidence in lung carcinoma (LLC) cell-bearing mice. This is mainly mediated by functional cytotoxic T lymphocyte-mediated oncolytic activity and inhibition of cancer proliferation- and metastasis-related genes. Moreover, TBCM-induced DCs can also generate memory CD4 T cells and exert long-term tumor prevention effects. In conclusion, our findings suggest that TBCM (Rv1885c), a novel TLR4 agonist, could be used as an immunoadjuvant for DC-based cancer immunotherapy.

Biochemical Study in Ehrlich Carcinoma Cells-bearing Mice Treated with Arsenic Trioxide and Cisplatin

Biochemical Study in Ehrlich Carcinoma Cells-bearing Mice Treated with Arsenic Trioxide and Cisplatin

Liposomal Artificial Red Blood Cell-Based Carbon Monoxide Donor Is a Potent Renoprotectant against Cisplatin-Induced Acute Kidney Injury.

Cisplatin (CDDP) is an essential anti-tumor agent for chemotherapeutic regimens against various types of cancer. However, the progression of nephrotoxicity, which is the main adverse effect of CDDP, leads to discontinuation of CDDP chemotherapy. Therefore, development of a renoprotectant against CDDP-induced nephrotoxicity is crucial. Here, the potential of a carbon monoxide (CO)-loaded hemoglobin-vesicle (CO-HbV) as a renoprotectant for CDDP-induced nephrotoxicity was evaluated for its renoprotective effects against CDDP-induced nephrotoxicity, inhibitory effects on the anti-tumor activity of CDDP, and anti-tumor activity. In healthy mice, after pretreatment with either saline, HbV, or CO-HbV prior to CDDP administration, only the CO-HbV pretreatment group ameliorated the progression of CDDP-induced nephrotoxicity by suppressing apoptosis via caspase-3. In experiments using B16-F10 melanoma cells, the half-maximal inhibitory concentration of CDDP decreased with co-incubation with CO-HbV, owing to the anti-tumor activity of CO. CO-HbV pretreatment had no impact on the anti-tumor activity of CDDP in B16-F10 melanoma cell-bearing mice, which was consistent with the results of the cell experiment. Furthermore, CO-HbV pretreatment improved body growth and survival rates. In conclusion, CO-HbV pretreatment is a potent renoprotectant for CDDP-induced nephrotoxicity, allowing treatment with CDDP to be conducted without failure of cancer treatment.

Cell membrane breakage and triggering T cell infiltration are involved in human telomerase reverse transcriptase (hTERT) promoter-driven novel peptide KK-64 for liver cancer gene therapy

ABSTRACT Liver cancer is an aggressive malignancy with exhibits both high mortality and morbidity. The current treatment options are associated with several limitations, novel specific anti-cancer drugs are urgently needed to improve liver cancer treatment. In this study, a new peptide KK-64 was designed, and it showed strong cytotoxicity against liver cancer cells. To obtain the tumor targeting property, a plasmid that contains KK-64 DNA fragment and driven by human telomerase reverse transcriptase (hTERT) promoter was constructed. pcTERT-kk-64 plasmid was found to specifically inhibit the viability of liver cancer cells HepG2, induce substantial apoptosis as well as damage to the cell membranes, but had minimal effects toward normal liver HL-7702 cells. Furthermore, pcTERT-kk-64 plasmids was also noted to significantly attenuate migration and invasion of HepG2 cells. The anti-tumor effect of pcTERT-kk-64 plasmid was also observed in H22 cell-bearing mice, and it appeared to cause significant tumor regression, trigger tumor cell apoptosis, and infiltrate cytotoxicity T cells to the tumor tissues after plasmids injection. Thus, pcTERT-kk-64 plasmids showed both strong cytotoxicity and tumor selectivity in vitro and in tumor-bearing mice in liver cancer models.

Stimuli-Responsive Drug Delivery of Doxorubicin Using Magnetic Nanoparticle Conjugated Poly(ethylene glycol)-g-Chitosan Copolymer.

Stimuli-responsive nanoparticles are regarded as an ideal candidate for anticancer drug targeting. We synthesized glutathione (GSH) and magnetic-sensitive nanocomposites for a dual-targeting strategy. To achieve this goal, methoxy poly (ethylene glycol) (MePEG) was grafted to water-soluble chitosan (abbreviated as ChitoPEG). Then doxorubicin (DOX) was conjugated to the backbone of chitosan via disulfide linkage. Iron oxide (IO) magnetic nanoparticles were also conjugated to the backbone of chitosan to provide magnetic sensitivity. In morphological observation, images from a transmission electron microscope (TEM) showed that IO nanoparticles were embedded in the ChitoPEG/DOX/IO nanocomposites. In a drug release study, GSH addition accelerated DOX release rate from nanocomposites, indicating that nanocomposites have redox-responsiveness. Furthermore, external magnetic stimulus concentrated nanocomposites in the magnetic field and then provided efficient internalization of nanocomposites into cancer cells in cell culture experiments. In an animal study with CT26 cell-bearing mice, nanocomposites showed superior magnetic sensitivity and then preferentially targeted tumor tissues in the field of external magnetic stimulus. Nanocomposites composed of ChitoPEG/DOX/IO nanoparticle conjugates have excellent anticancer drug targeting properties.

Blockade of deubiquitinase YOD1 degrades oncogenic PML/RARα and eradicates acute promyelocytic leukemia cells

In most acute promyelocytic leukemia (APL) cells, promyelocytic leukemia (PML) fuses to retinoic acid receptor α (RARα) due to chromosomal translocation, thus generating PML/RARα oncoprotein, which is a relatively stable oncoprotein for degradation in APL. Elucidating the mechanism regulating the stability of PML/RARα may help to degrade PML/RARα and eradicate APL cells. Here, we describe a deubiquitinase (DUB)-involved regulatory mechanism for the maintenance of PML/RARα stability and develop a novel pharmacological approach to degrading PML/RARα by inhibiting DUB. We utilized a DUB siRNA library to identify the ovarian tumor protease (OTU) family member deubiquitinase YOD1 as a critical DUB of PML/RARα. Suppression of YOD1 promoted the degradation of PML/RARα, thus inhibiting APL cells and prolonging the survival time of APL cell-bearing mice. Subsequent phenotypic screening of small molecules allowed us to identify ubiquitin isopeptidase inhibitor I (G5) as the first YOD1 pharmacological inhibitor. As expected, G5 notably degraded PML/RARα protein and eradicated APL, particularly drug-resistant APL cells. Importantly, G5 also showed a strong killing effect on primary patient-derived APL blasts. Overall, our study not only reveals the DUB-involved regulatory mechanism on PML/RARα stability and validates YOD1 as a potential therapeutic target for APL, but also identifies G5 as a YOD1 inhibitor and a promising candidate for APL, particularly drug-resistant APL treatment.

The JAK2 inhibitor TG101209 exhibits anti-tumor and chemotherapeutic sensitizing effects on Burkitt lymphoma cells by inhibiting the JAK2/STAT3/c-MYB signaling axis

Constitutive activation of JAK2/STAT3 is a major oncogenic signaling event involved in the development of Burkitt lymphoma (BL). In the present study, we investigated the antilymphoma activity of TG101209, a specific JAK2 inhibitor, on EBV-positive and EBV-negative Burkitt lymphoma cell lines and primary BL cells. The results showed that TG101209 had a significant antilymphoma effect by inhibiting BL cell growth and inducing apoptosis along with cell differentiation toward mature B cells in vitro. We also found that TG101209 displayed significant synergistic action and a sensitizing effect on the anti-Burkitt lymphoma activity of doxorubicin. In vivo experiments indicated that TG101209 could suppress tumor growth and prolong the overall survival of BL cell-bearing mice. The mechanistic study indicated that TG101209, by suppressing the JAK2/STAT3/c-MYB signaling axis and crosstalk between the downstream signaling pathways, plays an antilymphoma role. These data suggested that TG101209 may be a promising agent or alternative choice for the treatment of BL.

P13.10 Chemoattraction of glioma cells in a local hydrogel trap and immune control associated with improved survival and cognitive functions in a mouse model of glioblastoma resection

Abstract BACKGROUND Glioblastoma (GB) is the most aggressive brain primary tumor. The prognosis remains poor mainly due to the invasiveness of glioma cells, radio and/or chemoresistance and GB-induced immunosuppressive environment. Here, we propose to use a local delivery system based on a biocompatible hydrogel containing the chemopeptide urotensin II (hUII) or a biased synthetic analog DAB8-hUII, to “trap” GB cells, and/or to control immune cells expressing its G protein-coupled receptor UT, leading to tumor regression and neurological benefit, in a mouse model of GB resection. MATERIAL AND METHODS In vitro, invasion towards UII/analog across different hydrogels or glue of human or murine GB-GFP cell lines was evaluated in Boyden chamber and cloning ring assays. In vivo GB cells were intrastriatally xenografted, then resected while hydrogel- or glue-containing UII/analog was injected in the cavity resection. Behavioral tests, brain immunohistochemical analyses and mouse survival were then investigated. RESULTS In vitro, invasive capacity of human U87 and 42MG or murine GL261 and CT2A GB cells was stimulated by UII loaded into hydrogel-based hyaluronic acid supplemented with collagen or other chemicals, PNIPAAm-PEG, or thrombin-fibrin glue. In vivo, injection of UII- or DAB8-hUII-loaded glue into the cavity resection of GL261 and CT2A GB in C57BL/6 mice significantly improved survival compared with tumor and resected experimental conditions. Neurological status was also tested before and after GB resection. We found that GL261 and CT2A cell-bearing mice expressed altered spontaneous activity, emotion and cognitive functions. Intracavity injection of the glue improved resignation and anxiety and increased motor activity and cognition with a best cognitive recovery with hUII and DAB-8-hUII-loaded glue groups. Ex vivo brain analyses revealed high expression of UT and UII in some GB GFP-positive cells and macrophages within GB core and at the interface with the normal brain, GB cells expressing UT migrating along tortuous podocalyxin+ vascular components. In brains bearing hydrogel/hUII glue, vascularization appears modified and GFAP+ astrocytes and F4/80+ macrophages were highly recruited in the border of the cavity, compared with the other conditions. CONCLUSION A local glue containing UII may trap GB cells and remodel the tumor microenvironment responsible for survival and cognitive improvements, providing new option in the therapeutic arsenal of GB.

Abstract 1925: Effect of Averrhoa carambola extract on the antineoplastic and apoptotic activities in mice

Abstract Medicinal plants play significant roles in the treatment of different diseases. Averrhoa carambola has important clinical values in the treatment of cancer. However, its antineoplastic and apoptotic activities are still obscure. In this study, we were aimed to investigate those potentials of Averrhoa carambola in mice. For this, first the powder, prepared from the leaf and flower of Averrhoa carambola, were suspended with methanol to yield methanol extract of leaf and flower. Antineoplastic effect of leaf (25 and 50 mg/kg) against Ehrlich Ascites Carcinoma (EAC) was assessed by evaluating the viable tumor cell count, survival time, body weight and hematological parameters of EAC cell bearing mice. The result showed that the treatment with leaf significantly (p&amp;lt;0.05) decreased viable EAC cells and body weight gain thereby increasing the life span of EAC bearing mice and also revive the altered hematological (Hb, total RBC and WBC) parameters compare to those with normal values. Fluorescence microscopic view of 4,6-diamino-2-phenylindole (DAPI) staining demonstrated that leaf induced the alterations (i.e., nuclear condensation, fragmentation, membrane blabbing and apoptosis of cells) in the morphology of EAC cells. And, the quantitative analysis of p53 mRNA level by RT-PCR showed that p53 gene expression in leaf treated EAC cell was upregulated in respect to untreated control. These findings indicate that the induction of apoptosis in leaf-treated EAC cell was probably mediated through p53-dependent pathway. From this study, it can be concluded that the leaf of Averrhoa carambola exhibited potent antineoplastic and apoptotic activities that might be a potential agent for prevention of cancer in mice. Citation Format: Md. Zahid Hasan, Ayesha Siddika. Effect of Averrhoa carambola extract on the antineoplastic and apoptotic activities in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1925.

Heat shock protein 47 confers chemoresistance on pancreatic cancer cells by interacting with calreticulin and IRE1α.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most chemoresistant cancers. An understanding of the molecular mechanism by which PDAC cells have a high chemoresistant potential is important for improvement of the poor prognosis of patients with PDAC. Here we show for the first time that disruption of heat shock protein 47 (HSP47) enhances the efficacy of the therapeutic agent gemcitabine for PDAC cells and that the efficacy is suppressed by reconstituting HSP47 expression. HSP47 interacts with calreticulin (CALR) and the unfolded protein response transducer IRE1α in PDAC cells. Ablation of HSP47 promotes both the interaction of CALR with sarcoplasmic/endoplasmic reticulum Ca2+‐ATPase 2 and interaction of IRE1α with inositol 1,4,5‐triphosphate receptor, which generates a condition in which an increase in intracellular Ca2+ level is prone to be induced by oxidative stimuli. Disruption of HSP47 enhances NADPH oxidase‐induced generation of intracellular reactive oxygen species (ROS) and subsequent increase in intracellular Ca2+ level in PDAC cells after treatment with gemcitabine, resulting in the death of PDAC cells by activation of the Ca2+/caspases axis. Ablation of HSP47 promotes gemcitabine‐induced suppression of tumor growth in PDAC cell‐bearing mice. Overall, these results indicated that HSP47 confers chemoresistance on PDAC cells and suggested that disruption of HSP47 may improve the efficacy of chemotherapy for patients with PDAC.

Determination of in vitro antioxidant activity and in vivo antineoplastic effects against Ehrlich ascites carcinoma of methanolic extract of Sphagneticola calendulacea (L.) Pruski

Background and aimSphagneticola calendulacea (L.) Pruski (S. calendulacea) is a well-known medicinal plant that is widely used in traditional medicine. This study was conducted to evaluate the antioxidant and antineoplastic properties of S. calendulacea leaf. Experimental procedureMethanol was used as a solvent to prepare leaf extract from the dried leaf of S. calendulacea (MESL). We have evaluated the total phenolic and flavonoid contents of MESL, and using five different assays; we have also evaluated the antioxidant property of MESL. In vivo antineoplastic activity of MESL against Ehrlich ascites carcinoma (EAC) cells in experimental mice was also explored. ResultsThe phytochemical analysis of MESL exhibited the total phenolic, and total flavonoid contents in the dry extracts were 32.86 mg/gm of gallic acid equivalent and 127.26 mg/gm of catechin equivalent, respectively. Moreover, MESL also showed promising scavenging activity in all assays (IC50 value ≥70.5 μg/mL). In the in vivo antineoplastic assay, MESL showed increased EAC cell death at the doses of 50 mg/kg and 100 mg/kg body weight. MESL administration also induced apoptosis of EAC cells, significantly inhibited EAC cell growth, and increased the life span of EAC cell-bearing mice compared to EAC cell-bearing control mice. ConclusionsAll findings of this study suggest potential antioxidant and antineoplastic properties of MESL.