Doxorubicin Combination Therapy Research Articles

Gallic Acid Induces HeLa Cell Lines Apoptosis via the P53/Bax Signaling Pathway.

Cervical cancer is a type of cancer that originates from the endometrium and is more common in developed countries and its incidence is increasing day by day in developing countries. The most commonly prescribed chemotherapeutic drugs limit their use due to serious side effects and the development of drug resistance. For this reason, interest in new active ingredients obtained from natural products is increasing. This study aimed to reveal the apoptotic and antiproliferative effects of gallic acid and doxorubicin combination therapy against the HeLa cell line. We investigated the anti-cancer effects of doxorubicin and gallic acid in the human HeLa cervical cell line by using the MTT test, Nucblue staining for the identification of apoptotic cells due to nuclear condensation using fluorescent substance, and apoptotic markers P53 and Bax for the RT-PCR test. The highest cytotoxic effect obtained in the study, the highest increase in apoptotic induction, and a significant difference in P53/Bax levels were seen in the gallic acid/doxorubicin combination. Additionally, it was determined that gallic acid exhibited an effective cytotoxic effect on HeLa and HaCat cells within 48 and 72 h of application. The obtained findings show that the gallic acid/doxorubicin combination applied to HeLa cells may be an alternative treatment against both the cytotoxic effect size and the side effects of the chemotherapy agent.

Self-assembling peptides induced by eyes absent enzyme to boost the efficacy of doxorubicin therapy in drug-resistant breast cancer cells

Enzyme-induced self-assembly (EISA) is a recently developed nanotechnology technique in which small molecules are induced by cellular enzymes self-assembling into nanostructures inside cancer cells. This technique can boost the efficacy of chemotherapy drugs by avoiding drug efflux, inhibiting the cells’ DNA repair mechanisms, and targeting the mitochondria. In this work, we study the self-assembly of a short peptide and its fluorescence analogue induced by Eyes absent (EYA) tyrosine phosphatases to boost the efficacy of doxorubicin (DOX) therapy in drug-resistant types of breast cancer cells, MDA-MB-231 and MCF-7. The peptides Fmoc–FF–YP and NBD–FF–YP were synthesized with the solid-phase peptide synthesis (SPPS) method and analyzed with HPLC and MALDI-TOF. Dynamic light scattering was used to determine the size distribution of peptides exposed to the EYA enzyme in vitro. The presence of EYA enzymes in breast cancer cells was confirmed using the western blotting assay. The intracellular location of the peptide self-assembly was studied by imaging fluorescence NBD-tagged peptides. The efficacy of the peptide alone and with DOX was determined against MCF-7 and MDA-MB-231 using MTT and LIVE-DEAD assays. Nucleus and cytoplasm F-actin (Phalloidin) staining was used to determine cell morphology changes in response to the combination therapy of peptides/DOX. At an optimal concentration, the peptides are not toxic to the cells; however, they boost the efficacy of DOX against drug-resistant breast cancer cells. We used state-of-the-art computer-aided techniques to predict the molecular structure of peptides and their interactions with EYA. This study demonstrates an approach for incorporating non-cytotoxic components into DOX combination therapy, thereby avoiding increased systemic burden or adverse effects.

Liposome-enabled bufalin and doxorubicin combination therapy for trastuzumab-resistant breast cancer with a focus on cancer stem cells

Breast cancer stem cells (BCSCs) play a key role in therapeutic resistance in breast cancer treatments and disease recurrence. This study aimed to develop a combination therapy loaded with pH-sensitive liposomes to kill both BCSCs and the okbulk cancer cells using trastuzumab-sensitive and resistant human epidermal growth factor receptor 2 positive (HER2+) breast cancer cell models. The anti-BCSCs effect and cytotoxicity of all-trans retinoic acid, salinomycin, and bufalin alone or in combination with doxorubicin were compared in HER2+ cell line BT-474 and a validated trastuzumab-resistant cell line, BT-474R. The most potent anti-BCSC agent was selected and loaded into a pH-sensitive liposome system. The effects of the liposomal combination on BCSCs and bulk cancer cells were assessed. Compared with BT-474, the aldehyde dehydrogenase positive BCSC population was elevated in BT-474R (3.9 vs. 23.1%). Bufalin was the most potent agent and suppressed tumorigenesis of BCSCs by ∼50%, and showed strong synergism with doxorubicin in both BT-474 and BT-474R cell lines. The liposomal combination of bufalin and doxorubicin significantly reduced the BCSC population size by 85%, and inhibited both tumorigenesis and self-renewal, although it had little effect on the migration and invasiveness. The cytotoxicity against the bulk cancer cells was also enhanced by the liposomal combination than either formulation alone in both cell lines (p < 0.001). The liposomal bufalin and doxorubicin combination therapy may effectively target both BCSCs and bulk cancer cells for a better outcome in trastuzumab-resistant HER2+ breast cancer.

Danggui Buxue Tang improves therapeutic efficacy of doxorubicin in triple negative breast cancer via ferroptosis

Ethnopharmacological relevanceDanggui Buxue Tang (DBT) has been used for over 800 years to enhance Qi and nourish Blood, and it is particularly beneficial for cancer patients. Recent research has shown that combining DBT with chemotherapy agents leads to superior anti-cancer effects, thereby enhancing therapeutic efficacy. Aim of the studyThe aim of this study was to evaluate the effectiveness of a combination therapy involving doxorubicin (DOX) and Danggui Buxue Tang (DBT) in the treatment of triple-negative breast cancer (TNBC) and to elucidate the underlying mechanisms of action. Materials and methodsIn vitro experiments were performed using MDA-MB-231 and 4T1 cells, while in vivo experiments were carried out using MDA-MB-231 xenograft mice. The therapeutic effects of the combination therapy were evaluated using various techniques, including MTT assay, colony formation assay, flow cytometry, transwell assay, immunofluorescence, transmission electron microscopy (TEM), histological analysis, western blotting, and bioluminescence assay. ResultsDBT was found to enhance DOX's anti-TNBC activity in vitro by promoting ferroptosis, as evidenced by the observed mitochondrial morphological changes using TEM. The combination therapy was also found to reduce the expression of Nrf2, HO-1, and GPX4, which are all targets for ferroptosis induction, while simultaneously increasing ROS production. Additionally, the combination therapy reduced nuclear accumulation and constitutive activation of Nrf2, which is a significant cause of chemotherapy resistance and promotes cancer growth. In vivo experiments using an MDA-MB-231 xenograft animal model revealed that the combination therapy significantly reduced tumor cell proliferation and accelerated TNBC deaths by modulating the Nrf2/HO-1/GPX4 axis, with no evidence of tissue abnormalities. Moreover, the combination therapy exhibited a liver protective effect, and administration of Fer-1 was able to reduce the ROS formation produced by the DBT + DOX combination therapy. ConclusionThis study provides evidence that the combination therapy of DOX and DBT has the potential to treat TNBC by promoting ferroptosis through the Nrf2/HO-1/GPX4 axis.

Drug delivery by sonosensitive liposome and microbubble with acoustic-lens attached ultrasound: an in vivo feasibility study in a murine melanoma model

Conventional chemotherapy methods have adverse off-target effects and low therapeutic efficiencies of drug release in target tumors. In this study, we proposed a combination therapy of doxorubicin (DOX)-loaded ultrasound (US)-sensitive liposomal nanocarriers (IMP301), microbubbles (MBs) under focused US exposure using convex acoustic lens-attached US (LENS) to tumor treatment. The therapeutic effects of each treatment in a murine melanoma model were evaluated using contrast-enhanced US (CEUS) and micro-computed tomography (micro-CT) imaging, bioluminescence and confocal microscopy imaging, and liquid chromatography–mass spectroscopy (LC/MS) analysis. Tumor-bearing mice were randomly assigned to one of the following groups: (1) G1: IMP301 only (n = 9); (2) G2: IMP301 + LENS (n = 9); (3) G3: IMP301 + MB + LENS (n = 9); (4) G4: DOXIL only (n = 9); and (5) G5: IMP301 without DOXIL group as a control group (n = 4). Ten days after tumor injection, tumor-bearing mice were treated according to each treatment strategy on 10th, 12th, and 14th days from the day of tumor injection. The CEUS images of the tumors in the murine melanoma model clearly showed increased echo signal intensity from MBs as resonant US scattering. The relative tumor volume of the G2 and G3 groups on the micro-CT imaging showed inhibited tumor growth than the reference baseline of the G5 group. DOX signals on bioluminescence and confocal microscopy imaging were mainly located at the tumor sites. LC/MS showed prominently higher intratumoral DOX concentration in the G3 group than in other treated groups. Therefore, this study effectively demonstrates the feasibility of the synergistic combination of IMP301, MBs, and LENS-application for tumor-targeted treatment. Thus, this study can enable efficient tumor-targeted treatment by combining therapy such as IMP301 + MBs + LENS-application.

Drug-Eluting Porous Embolic Microspheres for Trans-Arterial Delivery of Dual Synergistic Anticancer Therapy for the Treatment of Liver Cancer.

Blockage of blood supply while administering chemotherapy to tumors, using trans-arterial chemoembolization (TACE), is the most common treatment for intermediate and advanced-stage unresectable Hepatocellular carcinoma (HCC). However, HCC is characterized by a poor prognosis and high recurrence rates (≈30%), partly due to a hypoxic pro-angiogenic and pro-cancerous microenvironment. This study investigates how modifying tissue stress while improving drug exposure in target organs may maximize the therapeutic outcomes. Porous degradable polymeric microspheres (MS) are designed to obtain a gradual occlusion of the hepatic artery that nourishes the liver, while enabling efficient drug perfusion to the tumor site. The fabricated porous MS are introduced intrahepatically and designed to release a combination therapy of Doxorubicin (DOX) and Tirapazamine (TPZ), which is a hypoxia-activated prodrug. Liver cancer cell lines that are treated with the combination therapy under hypoxia reveal a synergic anti-proliferation effect. An orthotopic liver cancer model, based on N1-S1 hepatoma in rats, is used for the efficacy, biodistribution, and safety studies. Porous DOX-TPZ MS are very effective in suppressing tumor growth in rats, and induction tissue necrosis is associated with high intratumor drug concentrations. Porous particles without drugs show some advantages over nonporous particles, suggesting that morphology may affect the treatment outcomes.

Dual targeting Bcl-2 and Bcl-xL augments osteosarcoma response to doxorubicin

Chemotherapy resistance is the major cause of treatment failure in osteosarcoma, the most common primary bone malignancy, and sensitizing therapeutic strategy is required to improve the clinical outcome. In this study, we discovered that navitoclax, a selective inhibitor of Bcl-2/Bcl-xL, effectively combats chemoresistance in osteosarcoma. Our research revealed that Bcl-2, but not Bcl-xL, is upregulated in osteosarcoma cells that are resistant to doxorubicin. However, venetoclax, a specific inhibitor of Bcl-2, did not exhibit activity against doxorubicin-resistant cells. Further analysis showed that depleting either Bcl-2 or Bcl-xL alone was insufficient to overcome doxorubicin resistance. Only by depleting both Bcl-2 and Bcl-xL significantly reduce the viability of doxorubicin-resistant cells. Similarly, navitoclax not only decreased the viability of doxorubicin-resistant cells but also acted synergistically with doxorubicin in cells sensitive to the drug. To confirm the ability of navitoclax to overcome doxorubicin resistance, we conducted experiments using multiple mouse models of osteosarcoma, both doxorubicin-sensitive and doxorubicin-resistant. The results provided confirmation that navitoclax is effective in overcoming doxorubicin resistance. Our findings demonstrate that simultaneous inhibition of Bcl-2 and Bcl-xL could serve as a novel strategy to sensitize chemoresistant osteosarcoma cells. Moreover, our study presents preclinical evidence supporting the potential of a navitoclax and doxorubicin combination therapy for the treatment of osteosarcoma, paving the way for future clinical investigations.

Chemoimmunotherapy with doxorubicin and caffeine combination enhanced ICD induction and T-cell infiltration in B16F10 melanoma tumors.

Majority of chemotherapeutic agents can elicit antitumor immunity and modulate the composition, density, function, and distribution of tumor infiltrating lymphocytes (TILs), to influence differential therapeutic responses and prognosis in cancer patients. The clinical success of these agents, particularly anthracyclines like doxorubicin, not only depends on their cytotoxic activity but also by the enhancement of pre-existing immunity primarily through induction of immunogenic cell death(ICD). However, resistance for the induction of ICD either intrinsic or acquired is a major hurdle for most of these drugs. To enhance ICD by these agents, it has become clear that blockade of adenosine production or its signaling need to be specifically targeted as they represent highly resistant mechanisms. Given the prominent role of adenosine mediated immunosuppression and resistance to ICD induction in tumor microenvironment, combination strategies that involve ICD induction and adenosine signaling blockade are further warranted. In the present study, we investigated the antitumor effect of caffeine and doxorubicin combination therapy against 3-MCA-induced and cell-line induced tumors in mice. Our results demonstrated significant tumor growth inhibition by the combination therapy of doxorubicin and caffeine against both carcinogen-induced and cell-line induced tumor models. In addition, significant T-cell infiltration and enhanced ICD induction evidenced by increased intratumoral calreticulin and HMGB1 levels, was observed in B16F10 melanoma mice. The possible mechanism behind the observed antitumor activity might be due to the enhanced ICD induction and subsequent T-cell infiltration by the combination therapy. To prevent the development of resistance and to enhance the antitumor activity of ICD inducing drugs like doxorubicin, combination with adenosine-A2A receptor pathway inhibitors like caffeine might be a potential strategy.

Combination therapy of doxorubicin and Sildenafil inhibits the growth of pediatric rhabdomyosarcoma

BackgroundOverexpression of phosphodiesterase type 5 (PDE5) has been detected in many types of malignant tumors. Sildenafil, a potent and selective inhibitor of a cGMP-specific PDE5, has been found to enhance the cytotoxic activity of different chemotherapeutic agents including doxorubicin. The combined therapy of doxorubicin with Sildenafil might reduce the possible side effects of chemotherapy while maintaining synergistic anticancer activity. The present study explored for the first time the effects of Sildenafil, alone and in combination with doxorubicin, on pediatric RMS cells.MethodsHuman RMS cells lines RH30 and RD were used. Western blotting and RT-PCR were performed to analyze PDE5 expression in RMS cells. Cell viability was determined using MTT assay. Cell migration was analyzed via transwell chambers, clonal growth and mitotic cell death were analyzed using the clonogenic assay. FACS analysis was performed to evaluate reactive oxygen species (ROS) and apoptosis.ResultsSildenafil significantly decreased cell viability and migration of RD and RH30 cells. The exposure of RMS cells to doxorubicin resulted in a dose-dependent decrease in their viability. Simultaneous administration of Sildenafil enhanced this effect. The incubation of the RMS cells with Sildenafil in the presence of doxorubicin significantly increased the proportion of apoptotic cells and ROS production compared to the treatment with Sildenafil alone.ConclusionsThe results of our study indicate a link between PDE5 inhibition by Sildenafil and decreased calcium signalling leading to significantly impaired viability, migration, and colony forming of RMS cells. Increased ROS production and apoptosis are mechanisms relevantly contributing to this observation.

Effects of Melatonin and Doxorubicin on Primary Tumor And Metastasis in Breast Cancer Model.

Melatonin exerts oncostatic effects on breast cancer via immunomodulation and antioxidation. Doxorubicin is an effective chemotherapeutic agent, but parallel studies also provide ample evidence of an off-target effect of Doxorubicin in breast cancer patients. Combinatorial use of doxorubicin and melatonin has not been comprehensively analyzed in breast cancer models. We hypothesized that the anti-oxidative, anti-proliferative and anti-inflammatory effects of melatonin could ameliorate the off-target effects of doxorubicin in breast cancer patients and enhance the anti-tumoral effects of doxorubicin. The goal of the study is to test this hypothesis in cancer cell lines and xenografted mice. The effects of Melatonin and doxorubicin on the cell viability were evaluated in 4T1-Brain Metastatic Tumor (4TBM). Furthermore, the effects of melatonin and doxorubicin on the primary tumors and systemic metastasis were evaluated in the xenografted mice. Lung and liver tissues were removed and metastasis analyses were performed. The levels of p65, phospho-STAT3, CD11b+, GR1+, Ki67, and cleaved caspase-3 proteins were determined with immunohistochemistry and western blot analysis. We examined the effects of melatonin and Melatonin+Doxorubicin combination therapy on 4TBM cells. Our results showed that doxorubicin inhibited the proliferation of metastatic breast cancer cells while melatonin did not affect cells. Tumor growth and metastasis were markedly suppressed in melatonin alone and in combination with doxorubicin. The expression of CD11b+ and GR1+ proteins, which are indicators of myeloid-derived suppressor cells (MDSCs), were noted to be reduced in both primary tumor and metastatic tissues in melatonin and doxorubicin groups. The combination of melatonin with doxorubicin reduced primary tumor growth and distant metastasis. Based on these results, melatonin is a promising candidate for combinatory use with conventional chemotherapeutics for breast cancer treatment.

A clinically relevant combination treatment of doxorubicin and cyclophosphamide does not induce hepatotoxicity in C57BL/6J mice

Chronic exposure to chemotherapeutics can lead to severe adverse events including hepatotoxicity. A combination chemotherapy regimen of doxorubicin (DOX) and cyclophosphamide (CPS) is employed in treatment of several cancers such as leukemia, lymphoma, and breast cancer. It is currently not well understood whether a combination therapy of DOX and CPS can induce hepatotoxicity. We therefore sought to determine whether co-administration of DOX and CPS at their clinically relevant doses and frequency results in hepatotoxicity. Male C57BL/6J mice received one intraperitoneal injection of saline or DOX-2mg /kg and CPS-50mg/kg once a week for 4 weeks. After the treatment period, liver histology and various serum biomarkers of hepatotoxicity were assessed. Co-treatment of DOX and CPS did not alter the serum levels of alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin, albumin, globulin, or total protein. Similarly, co-administration of DOX and CPS did not result in a noticeable change in liver histology. However, it was notable that the concomitant treatment with DOX and CPS resulted in a significant increase in serum levels of aspartate aminotransferase (AST). Elevated serum AST levels were also associated with increased serum creatinine kinase (CK) levels, suggesting that the elevated serum AST levels are likely due to muscle injury following the co-administration of DOX and CPS. Taken together, our results, for the first time, suggest that co-administration of DOX and CPS, at their clinically relevant doses and frequency, does not induce a significant hepatotoxicity in the mice.

Targeted delivery system using silica nanoparticles coated with chitosan and AS1411 for combination therapy of doxorubicin and antimiR-21

Herein, a novel targeted delivery system was developed for intracellular co-delivery of doxorubicin (DOX) as a chemotherapeutic drug, antimiR-21 as an oncogenic antagomiR. In this system, DOX was loaded into mesoporous silica nanoparticles (MSNs) and chitosan was applied to cover the surface of MSNs. AS1411 aptamer as targeting nucleolin and antimiR-21 were electrostatically attached onto the surface of the chitosan-coated MSNs and formed the final nanocomplex (AACS nanocomplex). The study of drug release was based on DOX release under pH 7.4 and 5.5. Cellular toxicity and cellular uptake assessments of AACS nanocomplex were carried out in nucleolin positive (C26, MCF-7, and 4T1) and nucleolin negative (CHO) cell lines using MTT assay and flow cytometry analysis, respectively. Also, Anti-tumor efficacy of AACS nanocomplex was evaluated in C26 tumor-bearing mice. Overall, the results show that the combination therapy of DOX and antimiR-21, using AACS nanocomplex, could combat the cancer cell growth rate.

Cognitive impairment resulting from treatment with docetaxel, doxorubicin, and cyclophosphamide

Breast cancer is the most commonly diagnosed cancer among women and it is estimated that about 30% of newly diagnosed cancers in women will be breast cancers. While advancements in treating breast cancer have led to an average 5-year survival rate of 90%, many survivors experience cognitive impairments as a result of chemotherapy treatment. Doxorubicin, cyclophosphamide, and docetaxel (TAC) are commonly administered as breast cancer treatments; however, there are few studies that have tested the cognitive effects of TAC. In the current study, 12-week-old female C57BL/6 mice received 4 weekly intraperitoneal injections of either saline or a combination therapy of doxorubicin and cyclophosphamide followed by 4 weekly docetaxel injections. Four weeks after the last injection, mice were tested for hippocampus-dependent cognitive performance in the Y-maze and the Morris water maze. During Y-maze testing, mice exposed to TAC exhibited impairment. During the water maze assessment, all animals were able to locate the visible and hidden platform locations. However, mice that received the TAC presented with a significant impairment in spatial memory retention on the probe trial days. TAC treatment significantly decreases the dendritic complexity of arborization in the dentate gyrus region of the hippocampus. In addition, comparative proteomic analysis revealed downregulation of proteins within key metabolic and signaling pathways associated with cognitive dysfunction, such as oxidative phosphorylation, ephrin signaling, and calcium signaling.

Image-Guided Radiofrequency Hyperthermia (RFH)-Enhanced Direct Chemotherapy of Hepatic Tumors: The Underlying Biomolecular Mechanisms.

PurposeTo evaluate the treatment effect of radiofrequency-induced hyperthermia (RFH) combined with intra-tumoral chemotherapy for rabbit VX2 liver tumors and explore the underlying mechanism that drives local hyperthermia-enhanced chemotherapy.Materials and MethodsVX2 cell lines and rabbits with liver VX2 tumors were randomly allocated to four treatment groups including: (1) combination therapy of Doxorubicin (DOX) plus hyperthermia/RFH (n=6); (2) DOX only; (3) hyperthermia/RFH only (n=6); and (4) phosphate-buffered saline-treated control (n=6). Cell viability and doxorubicin uptake by VX2 tumor cells were assayed using flow cytometry and fluorescence microscopy 24 h after treatments. Western blot was used to evaluate the expression level of heat shock protein 70 (HSP70) in tumor cells and tissues. For the harvested VX2 tumors, fluorescence microscopy was used to evaluate the distribution and penetration of doxorubicin in tumor tissues and HSP70 expression was analyzed by Western blot and immunohistochemistry.ResultsRFH enhanced the chemotherapeutic effect of doxorubicin in VX2 cells and rabbit liver VX2 tumors resulting in higher apoptosis and lower cell viability. Flowcytometry of VX2 cells showed more apoptotic cells in combination therapy of hyperthermia and DOX, compared with other three groups in-vitro experiments (45.80 ± 1.27% vs 20.66 ± 0.71%, vs 15.16 ± 0.81% and 0.62 ± 0.06%, respectively, p<0.01). The quantitative analysis by Western blot and immunohistochemistry showed increased expression of HSP70 in both VX2 tumor cells (1.28 ± 0.13 vs 0.64 ± 0.13 vs 0.83 ± 0.10 vs 0.15 ± 0.03, respectively, p<0.05) and tumors (1.47 ± 0.13 vs 0.51 ± 0.13 vs 0.74 ± 0.11 vs 0.16 ± 0.04, respectively, p <0.01). Fluorescence microscopy showed increased uptake of DOX in tumor cells in the combination therapy group.ConclusionsRFH/hyperthermia enhanced the chemotherapeutic effect of DOX in VX2 tumors by promoting the uptake of DOX and the expression HSP70 in tumors.

Evaluation of cytotoxicity and anticancer activity of kombucha and doxorubicin combination therapy on colorectal cancer cell line HCT-116.

BACKGROUND:Colorectal cancer is the third leading to death type of cancer in the world. The therapeutic guideline varied between different methods. As the main therapeutic guideline is chemotherapy, recent studies had shown utilization of natural products in combination with conventional medication, elevate the efficiency of chemotherapeutic methods. Kombucha is a traditional beverage obtained from the fermentation of green tea as a rich source of flavonoid medicinal plant. This study aimed to evaluate the natural potential of combination therapy of this natural product with doxorubicin as a chemotherapeutic agent.MATERIALS AND METHODS:The study was performed as in vitro evaluation of biological activity of kombucha on HCT-116 cell line (human colon cancer cell line). The cytotoxic effect of different kombucha beverages (fermented green tea) in comparison with green tea extract was evaluated by dimethylthiazolyl tetrazolium bromide (MTT) assay. In the next step, anticancer activity of doxorubicin as a general guideline chemotherapeutic agent in combination with kombucha was evaluated by cell cycle analysis and apoptosis assay flow cytometry. Apoptotic genes expression pattern was determined using real-time polymerase chain reaction. The experiments were designed in three independent replications and statistically analyzed using SPSS software.RESULTS:The results show that kombucha compared with the green tea extract caused more (1.2 fold) early apoptosis induction and G0/G1 phase arrest. Moreover, kombucha increased the expression levels of p21, p53, and B-cell leukemia/lymphoma 2 (Bcl-2)-associated X protein genes (2, 2.5, and 1.5 fold, respectively) while it decreased Bcl-2 gene expression level (5–8 fold) compared with doxorubicin alone. Combination of kombucha with doxorubicin shows 2-fold increased G0/G1 phase compared with the doxorubicin treatment.CONCLUSION:This result indicated that kombucha caused boosted anticancer activity of doxorubicin agent. These findings suggest that kombucha may be has an assistor and useful role in colorectal cancer treatment align with chemotherapy.

Biodegradable Implants Combined with Immunogenic Chemotherapy and Immune Checkpoint Therapy for Peritoneal Metastatic Carcinoma Postoperative Treatment.

Peritoneal seeding represents one of the most frequent sites of metastasis for late-stage gastrointestinal and gynecological cancer. At present, the major treatment method for peritoneal metastatic carcinoma (PMC) is the combination of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Nevertheless, the 5 year survival rate of patients after these treatments is still far from satisfactory. Here, we report a biodegradable implant co-loaded with doxorubicin (DOX) and anti-PD-1 monoclonal antibody (aPD-1) (BI@DOX+aPD-1) for a combination of immunogenic chemotherapy and immune checkpoint therapy for PMC postoperative treatment. The bio-implant is fabricated with oxidized dextran (ODEX) and 4-arm poly(ethylene glycol) amine (4-arm PEG-NH2) by Schiff's base reaction at mild conditions, with DOX and aPD-1 loaded inside during and after the fabrication process, respectively. In vitro studies confirmed the slow and sustained release of DOX and aPD-1 from the bio-implants. In vivo studies showed that the bio-implants could be gradually degraded and maintain relatively high concentrations of therapeutic agents in the mouse abdomen. In a murine CT26 PMC model, the BI@DOX+aPD-1 resulted in a 89.7% tumor-suppression rate after peritoneal implantation. Importantly, the combination therapy of DOX and aPD-1 in the bio-implant showed an excellent synergistic effect with a Q value of 2.35. This easy-fabricated bio-implant combined with DOX and aPD-1 should be promising for clinical PMC postoperative treatment.

Improving the efficacy of osteosarcoma therapy: combining drugs that turn cancer cell ‘don't eat me’ signals off and ‘eat me’ signals on

The long‐term survival of osteosarcoma patients with metastatic or recurrent disease remains dismal, and new therapeutic options are urgently needed. The purpose of our study was to compare the efficacy of CD47 mAb plus doxorubicin combination therapy in mouse models of osteosarcoma with CD47 mAb and doxorubicin monotherapy. Forty‐eight NOD scid gamma (NSG) mice with intratibial MNNG/HOS tumors received CD47 mAb, doxorubicin, combination therapy, or control IgG treatment. Twenty‐four mice (n = 6 per group) underwent pre‐ and post‐treatment magnetic resonance imaging (MRI) scans with the macrophage marker ferumoxytol, bioluminescence imaging, and histological analysis. Tumor ferumoxytol enhancement, tumor flux, and tumor‐associated macrophages (TAM) density were compared between different groups using a one‐way ANOVA. Twenty‐four additional NSG mice underwent survival analyses with Kaplan–Meier curves and a log‐rank (Mantel–Cox) test. Intratibial osteosarcomas demonstrated significantly stronger ferumoxytol enhancement and significantly increased TAM quantities after CD47 mAb plus doxorubicin combination therapy compared to CD47 mAb (P = 0.02) and doxorubicin monotherapy (P = 0.001). Tumor‐bearing mice treated with CD47 mAb plus doxorubicin combination therapy demonstrated significantly reduced tumor size and prolonged survival compared to control groups that received CD47 mAb (P = 0.03), doxorubicin monotherapy (P = 0.01), and control IgG (P = 0.001). In conclusion, CD47 mAb plus doxorubicin therapy demonstrates an additive therapeutic effect in mouse models of osteosarcomas, which can be monitored with an immediately clinically applicable MRI technique.

Abstract 3478: APC loss mediates doxorubicin response in breast cancer via changes in intracellular drug concentration and DNA repair pathways

Abstract Chemoresistance is one of the leading causes of breast cancer related deaths. Understanding the molecular basis for chemoresistance is essential for novel therapeutic advancement to improve patient outcome. The Adenomatous Polyposis Coli (APC) tumor suppressor is either mutated or hypermethylated in up to 70% of sporadic breast cancer; however, little is known about how APC loss contributes to chemoresistance. Using mammary tumor cells isolated from the ApcMin/+ mouse crossed to the Polyoma middle T antigen (PyMT) transgenic model, we demonstrated that APC loss decreased doxorubicin (DOX) induced apoptosis. DOX, a commonly used chemotherapeutic in breast cancer, inhibits topoisomerase IIa, resulting in double stranded DNA breaks, resulting in cell cycle arrest to allow repair or apoptosis. We made the novel observation that APC loss in MMTV-PyMT;ApcMin/+ cells activated signal transducer and activator of transcription 3 (STAT3) thereby increasing the expression of the drug efflux pump, multidrug resistance protein 1 (MDR1). Therefore, we hypothesized that APC loss prevents doxorubicin-mediated cell death through: 1) reduced intracellular DOX and 2) alterations in DNA damage and repair. To investigate the intracellular accumulation of DOX, we first used calcein incorporation assay and demonstrated that APC loss increased MDR1 activity, which was restored by an MDR1 inhibitor. In addition, MDR1 inhibition sensitized the MMTV-PyMT;ApcMin/+ cells to DOX-mediated apoptosis. To investigate the effect of APC loss on DNA damage repair pathways, we initially monitored damage recognition pathways after 24-hour DOX treatment. The MMTV-PyMT;ApcMin/+ cells exhibited decreased γH2AX and ataxia-telangiectasia mutated (ATM) phosphorylation following DOX treatment compared to controls, suggesting decreased DNA damage either through decreased intracellular DOX or enhanced DNA repair. Decreased phosphorylation of Chk1 and Chk2 was also observed in DOX-treated MMTV-PyMT;ApcMin/+ cells. Preliminary data to investigate if this decreased DNA damage was due to increased DNA damage repair, via monitoring γH2AX expression throughout treatment and recovery from DOX, suggest enhanced DNA repair in MMTV-PyMT;ApcMin/+ cells. Using the ATM inhibitor, we observed an increase in DOX sensitivity in MMTV-PyMT;ApcMin/+ cells. Alternatively, ATR inhibition did not affect DOX-mediated apoptosis. We will further investigate the efficiency of repair pathways through reporter plasmids and radiation induced damage to separate the drug transport alterations. Finally, we will test whether combination therapy of doxorubicin with an MDR1 inhibitor will reduce tumor burden in vivo. Taken together, APC loss mediates DOX resistance via reducing intracellular DOX and increasing DNA damage repair demonstrating the potential use of combination therapy to overcome chemoresistance. Citation Format: Casey Stefanski, Kaitlyn Keffler, Stephanie McClintock, Lauren Milac, Jenifer Prosperi. APC loss mediates doxorubicin response in breast cancer via changes in intracellular drug concentration and DNA repair pathways [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3478.

Assembly simulation and synergistic chemotherapy of TPGS derivative functionalized polymersomes in hepatocellular carcinoma.

Aim: Multidrug resistance and severe side effects lead to poor therapeutic efficacy of monotherapy against hepatocellular carcinoma. Here, a targeting codelivery nanocomposite system is constructed to reverse tumor multidrug resistance and realize a combination therapy of doxorubicin and oxaliplatin. Methods & materials: We simulate the composited structure ofTPGS-lactobionic acid conjugate (TLA) modified methyl poly(ethylene glycol)-polylactide(mPP) polymersomes using dissipative particle dynamics. Cellular uptake and drug retention, cytotoxicity, in vivo antitumor efficacy and toxicity were evaluated. Results: TLA/mPP composited polymersomes improved intracellular accumulation of coloaded drugs via active targeting ability and P-gp efflux inhibition, leading to strong cytotoxicity against HepG2/ADR cells and potent tumor inhibition (93.5%) for HepG2/ADR tumor. Conclusion: TLA/mPP composited polymersomes represent a promising multifunctional nanoplatform against hepatocellular carcinoma.

Safety and efficacy of combination therapy with apatinib and doxorubicin in metastatic soft tissue sarcomas: an observational study from multiple institutions.

Purpose: Apatinib has shown effectiveness in treating sarcoma. This study aimed to assess the safety and efficacy of apatinib and doxorubicin combination therapy in metastatic soft tissue sarcomas (STS) and to compare the therapeutic effects of two treatments (apatinib after doxorubicin vs apatinib plus doxorubicin) on STS.Patients and methods: A total of 76 patients with metastatic STS who received apatinib and doxorubicin between May 2016 and June 2017 were retrospectively reviewed. Patients were divided into either the apatinib after doxorubicin group (in which apatinib was used after six cycles of doxorubicin chemotherapy) or the apatinib plus doxorubicin group (in which apatinib was used in combination with doxorubicin chemotherapy).Results: There were 55 patients in the apatinib after doxorubicin group and 21 patients in the apatinib plus doxorubicin group. There were significant differences between the apatinib plus doxorubicin group and the apatinib after doxorubicin group in the objective response rate (57.14% vs 25.45%, respectively, p=0.016) and average change from baseline in the target lesion size (−41.71±43.75% vs −1.89±51.61%, respectively, p=0.03). There were no significant differences in disease control rate (85.71% vs 63.64%, p=0.093) and median progression-free survival (8.8 months vs 10.3 months, p=1). Grade 3–4 adverse events were more common with apatinib plus doxorubicin than with apatinib after doxorubicin, and these included leukopenia (5.45% vs 38.1%, respectively, p=0.001), anemia (7.27% vs 28.57%, respectively, p=0.023), oral mucositis (3.64% vs 19.05%, respectively, p=0.046), transaminase increases (0% vs 14.29%, respectively, p=0.011).Conclusion: Our results do not support the use of apatinib plus doxorubicin for metastatic STS unless the specific objective is tumor shrinkage.