Tumor Growth Inhibition Effect Research Articles

Abstract A039: IGFBP5 is induced by tumor-suppressive naïve stromal cells and regulates GAS2-associated apoptosis in rhabdomyosarcoma

Abstract Stromal cells can have either suppressive or stimulatory effects on tumor progression. However, this diverse collection of cells is still poorly characterized in soft-tissue sarcomas. Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma in childhood with molecular features of skeletal muscle differentiation. In this study, we explored tumor growth-regulatory signaling between differentially educated non-malignant mesenchymal stromal cells and malignant tumor cells in RMS. Xenograft experiments in mice were designed to provide functional evidence for alterations in tumor behavior linked to tumor-associated stromal cells. Molecular characterization was performed on the Clariom D platform, by gene set enrichment analysis, cell culture validation of deregulated genes, and finally, by clinicopathological validation in a discovery cohort (N=101) and a validation cohort (N=147). The results revealed transient tumor growth-suppressive paracrine effects of naïve orthotopic stromal cells derived from skeletal muscle. These effects were easily abolished if the stromal cells were pre-exposed to RMS cells, either short-term in vitro, or long-term in hindlimb muscle in vivo. Explorative analyses of RMS cells exposed to naïve stromal cells identified insulin-like growth factor binding protein 5 (IGFBP5) as the top upregulated gene, with an ability to induce Caspase 3/7 activation and growth arrest. The gene coding for connective tissue growth factor (CTGF) was identified as the major prosurvival factor being downregulated. Analysis of patient cohorts consistently demonstrated an association between IGFBP5, growth arrest specific protein 2 (GAS2), lower disease stage and favorable survival. Altogether, our study identifies a novel anti-tumor growth mechanism with conditionally deregulated genes linked to apoptosis and differentiation in RMS. The results provide support for continued studies on tumor growth-regulatory mechanisms induced by tumor-surrounding stromal cell subsets at primary and metastatic sites in sarcoma. Citation Format: Monika Ehnman, Karim Katkhada, Liu Zhen Meng, Yue Zhang, Binbin Zhao, Shanlin Tong, Aditi Kallai, Arne Östman, Nick Tobin. IGFBP5 is induced by tumor-suppressive naïve stromal cells and regulates GAS2-associated apoptosis in rhabdomyosarcoma [abstract]. In: Proceedings of the AACR Special Conference: Sarcomas; 2022 May 9-12; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2022;28(18_Suppl):Abstract nr A039.

Hyaluronidase responsive second near-infrared fluorescent nanocomplex for combined HER2 blockade and chemotherapy of HER2+ breast cancer

The human epidermal growth factor receptor-2-positive (HER2+) type is aggressive and has poor prognosis. Although anti-HER2 therapy alone or in combination with other treatment regimens showed significant improvement in survival outcomes, breast cancer patients are still suffering from tumor relapse and severe dose-limiting side effects. Thus, there is still an unmet challenge to develop effective therapeutic agents for HER2+ breast cancer treatment with minimized side effects. Herein, we produced a stimuli-responsive and tumor-targeted hyaluronic acid (HA) nanocomplex that combined HER2 blockade and chemotherapy for effective HER2+ breast cancer therapy. A hydrophobic NIR-II dye, IR1048, was covalently linked with HA to form a spherical HA-IR1048 nanoparticle (HINP), with Herceptin conjugated on the surface and paclitaxel (PTX) encapsulated inside. The fluorescent signals from the yielding Her-HINP/PTX are quenched originally, but a strong NIR-II signal is generated when HINP is degraded by the hyaluronidase that is overexpressed in breast tumors, thus allowing the tracking and visualization of Herceptin and PTX accumulation. Her-HINP/PTX peaked in HER2+ tumors at 24 h post injection as imaged by NIR-II fluorescent imaging. A significantly improved tumor growth inhibition effect was observed after five systemic treatments compared to single PTX (3.71 ± 0.41 times) or Herceptin (5.98 ± 0.51 times) treatment in a HER2-overexpressed breast cancer mouse model with prolonged survival. Collectively, the designed Her-HINP/PTX presents a new hyaluronidase-responsive and HER2 blockade nanoformulation that can visualize the accumulation of nanocomplexes and release drugs inside tumors for combined HER2+ breast cancer therapy with a great promise for translational study. Statement of significanceThe high expressions of a protein called human epidermal growth factor receptor 2 (HER2) in breast tumors make this subtype of cancer aggressive. Currently, chemotherapy combined with a HER2 antibody, Herceptin, is a preferred approach for HER2-positive breast cancer therapy. However, these breast cancer patients still suffer from tumor relapse and severe side effects because various therapeutic agents have inherent different biodistributions, resulting in insufficient treatment effects and unfavorable normal organ uptake of these therapeutic agents. Herein, we produced a nanocomplex carrying both Herceptin and chemotherapy drug to simultaneously deliver two drugs into tumors for efficient HER2+ tumor treatment with minimized side effects, providing new insights for designing a combined therapy strategy.

Albumin-Coated Framework Nucleic Acids as Bionic Delivery System for Triple-Negative Breast Cancer Therapy

Triple-negative breast cancer (TNBC) is a subtype of breast cancer, and it has aggressive and more frequent tissue metastases than other breast cancer subtypes. Because the proliferation of TNBC tumor cells does not depend on estrogen receptor (ER), progesterone receptor (PR), and Erb-B2 receptor tyrosine kinase 2 (HER2) and lacks accurate drug targets, conventional chemotherapy is challenging to be effective, and adverse reactions are severe. At present, the treatment strategy for TNBC generally depends on a combination of surgery, radiotherapy, and chemotherapy. Conventional administration methods have minimal effects on TNBC and cause severe damage to normal tissues. Therefore, it is an urgent task to develop an efficient and practical way of drug delivery and open up a new horizon of targeted therapy for TNBC. In our work, bovine serum albumin (BSA) acted as the protective film to prolong the circulation time of the tetrahedral framework nucleic acid (tFNA) delivery system and resist immune clearance in vivo. tFNA was used as a carrier loaded with DOX and AS1411 aptamers for the targeted treatment of triple-negative breast cancer. Compared with existing approaches, this optimized system exhibits stronger tumor-targeting so that tFNAs can be more concentrated around the tumor tissue, reducing DOX toxicity to other organs. This bionic delivery system exhibited effective tumor growth inhibition in the TNBC mice model, offering the clinical potential to promote the treatment of TNBC with great potential for clinical translation.

Gold-based nanoparticles realize photothermal and photodynamic synergistic treatment of liver cancer and improve the anaerobic tumor microenvironment under near-infrared light.

In order to solve the different pains caused by traditional cancer treatment methods such as surgical treatment, the nano-drug delivery system provides new ideas for cancer treatment. In this paper, a novel anti-tumor therapy nanoparticle, P(AAm-co-AN)-AuNRs@CeO2-Ce6(PA/Ce6), is prepared, which provides a novel idea for liver cancer treatment. The CeO2-coated gold nanorods were grafted onto the surface of the temperature-sensitive polymer P(AAm-co-AN)-CTPD. The photosensitizer Ce6 is loaded on the surface of the nanoparticles and the polymer layer. CeO2 can effectively alleviate the tumor anaerobic microenvironment, and under 808 nm near-infrared (NIR) excitation, the gold nanorods achieve photothermal conversion to induce local heating, which leads to the phase transition of the polymer layer and realizes a controllable release mechanism. In addition, 660 nm NIR light can effectively induce Ce6 to produce singlet oxygen, thereby effectively killing cancer cells. Under the 808 nm laser irradiation within 600 s, the PA/Ce6 solution can heat up to about 60°C, which was enough to ablate both cancer cells and tumor tissues. When the temperature was 50°C, the cumulative release rate of Ce6 was 95.31%. Under the 808 nm laser irradiation, oxygen production capacity of PA/Ce6 was higher and can effectively reduce the content of hydrogen peroxide in cancer cells. Compared to free Ce6, the reactive oxygen species-mediated fluorescence of PA/Ce6 nanoparticles was greater. The cell viability and migration of HepG2 cells were decreased after the 660 and 880 nm lasers were irradiated at the same time. The cancer cells were further inhibited, showing a good in vitro anti-tumor effect. PA-DOX showed the best tumor growth inhibitory effect under NIR laser irradiation and had no acute toxicity in vivo. Due to the existence of AuNRs, nanoparticles had high-efficiency photothermal conversion ability to achieve photothermal therapy. Ce6 can generate singlet oxygen under the excitation of 660 nm laser to realize photodynamic therapy. The experimental results also showed that PA/Ce6 can effectively decompose hydrogen peroxide under laser irradiation, aiming to effectively alleviate the anaerobic microenvironment of tumors. These indicate that PA/Ce6 plays a promising role for hepatocellular carcinoma treatment.

A Hoechst Reporter Enables Visualization of Drug Engagement In Vitro and In Vivo: Toward Safe and Effective Nanodrug Delivery.

Assessment of drug activation and subsequent interaction with targets in living tissues could guide nanomedicine design, but technologies enabling insight into how a drug reaches and binds its target are limited. We show that a Hoechst-based reporter system can monitor drug release and engagement from a nanoparticle delivery system in vitro and in vivo, elucidating differences in target-bound drug distribution related to drug-linker and nanoparticle properties. Drug engagement is defined as chemical detachment of drug or reporter from a nanoparticle and subsequent binding to a subcellular target, which in the case of Hoechst results in a fluorescence signal. Hoechst-based nanoreporters for drug activation contain prodrug elements such as dipeptide linkers, conjugation handles, and nanoparticle modifications such as targeting ligands to determine how nanomedicine design affects distribution of drug engaged with a subcellular target, which is tracked via cellular nuclear fluorescence in situ. Furthermore, the nanoplatform is amenable toward common maleimide-based linkers found in many prodrug-based delivery systems including polymer-, peptide-, and antibody-drug conjugates. Findings from the Hoechst reporter system were applied to develop highly potent, targeted, anticancer micelle nanoparticles delivering a monomethyl auristatin E (MMAE) prodrug comprising the same linkers employed in Hoechst studies. MMAE nanomedicine with the optimal drug-linker resulted in effective tumor growth inhibition in mice without associated acute toxicity, whereas the nonoptimal linker that showed broader drug activation in Hoechst reporter studies resulted in severe toxicity. Our results demonstrate the potential to synergize direct visualization of drug engagement with nanomedicine drug-linker design to optimize safety and efficacy.

Combinatory therapy of MRP1-targeted photoimmunotherapy and liposomal doxorubicin promotes the antitumor effect for chemoresistant small cell lung cancer

Small cell lung cancer (SCLC), considered a mortal recalcitrant cancer, is a severe healthcare issue because of its poor prognosis, early metastasis, drug resistance and limited clinical treatment options. In our previous study, we established a MRP1-targeted antibody-IR700 system (Mab-IR700) for near infrared photoimmunotherapy (NIR-PIT) which exhibited a promising therapeutic effect on drug resistant H69AR cells both in vitro and in vivo, though the tumor growth suppression effect did not last long with a single round of PIT treatment. To achieve a better anticancer effect, we have combined Mab-IR700-mediated NIR-PIT with liposomal doxorubicin (Doxil®) and investigated the in vitro and in vivo cytotoxicity by using a H69AR/3T3 cell co-culture model in which 3T3 cells were used to mimic stromal cells. Cytotoxicity experiments demonstrated the specificity of Mab-IR700 to H69AR cells, while cytotoxicity and flow cytometry experiments confirmed that H69AR cells were doxorubicin-resistant. Compared with Mab-IR700-mediated PIT or Doxil-mediated chemotherapy, the combination therapy exhibited the best cell killing effect in vitro and superior tumor growth inhibition and survival prolongation effect in vivo. Super enhanced permeability and retention (SUPR) effect was observed in both co-culture spheroids and tumor-bearing mice. Owing to an approximately 9-fold greater accumulation of Doxil within the tumors, NIR-PIT combined with Doxil resulted in enhanced antitumor effects compared to NIR-PIT alone. This photoimmunochemotherapy is a practical strategy for the treatment of chemoresistant SCLC and should be further investigated for clinical translation.

Tumor microenvironment responsive theranostic agent for enhanced chemo/chemodynamic/photothermal therapy

The specific characteristics of the tumor microenvironment (TME) and monotherapy always lead to poor therapy effects for tumors. Hereby, we have developed a smart multifunctional theranostic agent-SSMID (Se@SiO2@MnO2-ICG/DOX) nanocomposites (NCs) that could intelligently respond to the TME for enhanced chemotherapy/photothermal/chemodynamic therapy guided by magnetic resonance imaging (MRI). The SSMID NCs were composed of indocyanine green (ICG) and doxorubicin hydrochloride (DOX) co-loaded porous Se@SiO2 @MnO2. Under the specific conditions of the TME (slightly acidic, H2O2 and GSH overexpression), the MnO2 NPs were specifically decomposed and then SSMID released Mn2+, DOX and Se, which played roles in chemodynamic therapy (CDT), chemotherapy, protecting normal tissues and inhibiting tumor cells by modulating reactive oxygen species (ROS), respectively. MnO2 reacted with glutathione (GSH) and H2O2 to generate O2 and Mn2+, which alleviated tumor hypoxia to improve chemotherapy and depleted GSH to enhance oxidative stress for chemodynamic therapy. More importantly, SSMID NCs could simultaneously exert the photothermal therapy (PTT) effect with near-infrared laser irradiation and promote the release of Mn2+ and DOX to achieve enhanced chemotherapy/chemodynamic therapy. In addition, the released Mn2+ could be used as a T1-weighted MRI contrast agent to monitor tumor location. The SSMID NCs exhibited a pronounced tumor growth inhibitory effect and promising biological safety, which develop a new method to rationally design nano-theranostic agents with enhanced performance for anti-tumor.

Hexa-BODIPY-cyclotriphosphazene based nanoparticle for NIR fluorescence/photoacoustic dual-modal imaging and photothermal cancer therapy

Theranostic, which integrates the diagnosis and tumor treatment in tandem, is an emerging strategy in cancer treatment. Here, we report a novel and unique theranostic nanoparticle, HBCP NP, based on hexa-BODIPY cyclophosphazene (HBCP). Due to the unique bulky molecular structure of HBCP, this nanoparticle can simultaneously perform near-infrared (NIR) fluorescence imaging and photoacoustic imaging (PAI). Interestingly, since reactive oxygen species (ROS) generation of HBCP NPs is completely inhibited, ‘safe’ fluorescence imaging is possible without the risk of cell damage even under laser irradiation. Finally, NIR fluorescence imaging and PAI in 4T1 tumor-bearing mice demonstrated selective accumulation of HBCP NPs at tumor sites. In addition, HBCP NPs exhibited excellent photothermal effects under high-power laser irradiation, achieving effective tumor growth inhibition.

Abstract 1293: AZD0171 (anti-LIF) combines productively with chemotherapy and anti-PD-L1 in mouse models of cancer

Abstract Leukemic inhibitory factor (LIF) is an IL-6 family member involved in embryonic stem cell maintenance and protection from maternal immune-attack. Emerging evidence indicates that LIF biology is hijacked by some tumors to promote immunosuppressive tumor associated macrophages, cancer initiating cells and epithelial-mesenchymal transition (EMT). In patients treated with anti-PD-1/anti-PD-L1 antibodies (IO), baseline high LIF expression correlated with poor outcome (Loriot et al. 2021). In preclinical models, LIF blockade has separately been reported to sensitize tumors to IO and to chemotherapy (chemo), but the impact of LIF blockade on chemo/IO combination activity is unknown. We therefore evaluated the hypothesis that LIF blockade sensitizes tumors to chemo/IO combinations. AZD0171 is a monoclonal antibody that binds to LIF and prevents signaling through LIF receptor. A murine surrogate of AZD0171 (mAZD0171) was generated and tested in vivo using three syngeneic murine cancer models, and AZD0171 was tested in patient derived xenograft models. Monotherapy mAZD0171 induced tumor gene expression changes consistent with its proposed mechanism of action in the syngeneic CT26 colon tumor model; including elevated CD8 attracting chemokines (CXCL9/10), cDC1 transcription factor (Batf3) and reduced stem cell (CD44), EMT (CY61) and hypoxic/angiogenic signatures, including CXCL12. Flow cytometry analysis highlighted changes consistent with suppressive macrophage re-education (reduced CD206/elevated MHCII). mAZD0171 sensitized mouse tumors to both IO and chemo. mAZD0171 + anti-PD-L1 treatment reversed CD8 T cell exclusion in the D2A1-m2 model; a LIF expressing cancer associated fibroblast rich, anti-PD-L1 resistant mouse mammary tumor syngeneic model (Jungwirth et al. 2018). mAZD0171 + anti-PD-L1 treatment further inhibited D2A1-m2 growth versus (vs) anti-PD-L1 treatment alone. In a non-small cell lung carcinoma patient derived xenograft model, AZD0171 improved the tumor growth inhibitory effect of Carboplatin + Paclitaxel. The triplet combination of mAZD0171 plus chemo and IO had the most marked impact on both tumor microenvironment and tumor growth. mAZD0171 addition to oxaliplatin (OHP) or Docetaxel (DTX) chemotherapy plus anti-PD-L1 significantly elevated CD8 abundance and granzyme B expression in MC38 colon tumors. mAZD0171 + anti-PD-L1 + OHP or DTX improved inhibition of MC38 tumor growth (63% for OHP triplet vs 34% for anti-PD-L1 + OHP; 49% for DTX triplet vs 36% for anti-PD-L1 + DTX) and extended median survival times (P<0.05 vs anti-PD-L1+OHP/DTX). Together these data support the hypothesis that AZD0171 has the potential to sensitize solid tumors to chemotherapy/IO combinations. The safety and activity of AZD0171 is currently being assessed in a Ph2 clinical trial in combination with durvalumab (anti-PD-L1) and chemotherapy in metastatic pancreatic cancer (NCT04999969). Citation Format: Juliana Candido, Gozde Kar, Bairu Zhang, Grace Opoku-Ansah, Amit Grover, Elizabeth A. Kuczynski, Tim Slidel, Doug Palmer, Robert W. Wilkinsom, Nadia Luheshi, Jim Eyles. AZD0171 (anti-LIF) combines productively with chemotherapy and anti-PD-L1 in mouse models of cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1293.

Abstract 2303: The WEE1 inhibitor Debio 0123 enhances the efficacy of standard of care DNA damaging agents in lung cancer models

Abstract Introduction: The WEE1 tyrosine kinase is activated upon DNA damage and regulates the G2-M and S phase cell cycle checkpoints. Inhibition of WEE1, in conjunction with genetic alterations and/or addition of a DNA damaging agent, results in mitotic catastrophe and apoptosis of cancer cells, offering an attractive approach to treating cancer. Debio 0123 is a WEE1 specific inhibitor previously shown to sensitize cancer cells to DNA damaging agents which is currently being assessed in combination with carboplatin in patients with advanced solid malignancies. Small cell lung cancer (SCLC) is an aggressive disease with poor clinical outcomes that carries a high mutational burden and genomic instability. Here we investigated the ability of Debio 0123 to enhance SCLC response to standard of care (SOC) DNA damaging agents carboplatin and etoposide in vitro and in vivo. Methods: SCLC cell lines were treated with Debio 0123 alone or in combination with etoposide or carboplatin in vitro and apoptosis assessed by flow cytometry. In vivo SCLC patient derived- or cell line derived-xenograft (PDX or CDX, respectively) models were treated with Debio 0123 orally in combination with either carboplatin or etoposide alone or as a triple combination. Tumor growth inhibition was assessed over 3 cycles of treatment and tolerability of the combinations evaluated by monitoring body weight changes. Results: Debio 0123 synergized with carboplatin and etoposide in vitro leading to a significant increase in the induction of apoptosis. Additionally, Debio 0123 significantly improved the tumor growth inhibitory effect of etoposide and carboplatin in both PDX and CDX models of SCLC in vivo. Triple combination of carboplatin, etoposide and Debio 0123 was well tolerated at therapeutically relevant dosing and resulted in significantly improved tumor response when compared to carboplatin and etoposide treatments alone or to the double combination. Conclusions: Taken together these results highlight that inhibiting WEE1 with Debio 0123 significantly improves tumor response to SOC DNA damaging agents in models of SCLC, providing the foundation for future clinical exploration of Debio 0123 in SCLC. Citation Format: Luke Piggott, Anne Vaslin-Chessex, Noemie Luong, Benjamin Tschumi, Gregoire Vuagniaux. The WEE1 inhibitor Debio 0123 enhances the efficacy of standard of care DNA damaging agents in lung cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2303.

Abstract 5623: CD137 humanized mice for preclinical efficacy evaluation of therapeutic antibodies

Abstract CD137 (41-BB, tumor necrosis factor receptor superfamily 9), expressed on activated T cells and NK cells, has gained increased attention as an anti-tumor target because of remarkable clinical efficacy using either a single agent or in combination with other immune checkpoint inhibitors. We constructed CD137 humanized mice based on two different backgrounds, C57BL6 and BALB/c mice, as well as dual-target and triple-target mice crossbred with PD1/PDL1 humanized mice to create an ideal model to study CD137 target drugs. The normal immune cell population in peripheral blood were not affected in CD137 humanized mice, and hCD137 was expressed on T cells after the stimulation with a anti CD3 antibody. We verified the efficacy of anti-CD137 drugs in BALB/c-hCD137 mice inoculated with different cancer cell lines (i.e. CT26, EMT6 and 4T1). The drug Urelumab showed a dramatic response in the hCD137 mice model inoculated with CT26 and EMT6 but not with 4T1 cell line. In a rechallenge study, no tumors grew in tumor-free mice previously treated with Urelumab, with effector memory T cells increased in peripheral blood, indicating Urelumab has a relatively long-lasting anti-tumor effect. The combination of Urelumab and anti-PD1 has a stronger tumor growth inhibition effect than that of anti-CD137 or anti-PD1 monotherapy on dual-target or triple target mice. These data show that the humanized CD137 mouse is a suitable model for evaluating the monotherapies or combination therapies targeting CD137. Citation Format: Yunlong Jiang, Tingting Gu, Weiwei Yu, Hongyan Sun, Mingkun Zhang, Juan Liang, Shuai Li, Cunxiang Ju, Jing Zhao, Xiang Gao, Mark W. Moore. CD137 humanized mice for preclinical efficacy evaluation of therapeutic antibodies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5623.

Extracellular vimentin mimics VEGF and is a target for anti-angiogenic immunotherapy

Anti-angiogenic cancer therapies possess immune-stimulatory properties by counteracting pro-angiogenic molecular mechanisms. We report that tumor endothelial cells ubiquitously overexpress and secrete the intermediate filament protein vimentin through type III unconventional secretion mechanisms. Extracellular vimentin is pro-angiogenic and functionally mimics VEGF action, while concomitantly acting as inhibitor of leukocyte-endothelial interactions. Antibody targeting of extracellular vimentin shows inhibition of angiogenesis in vitro and in vivo. Effective and safe inhibition of angiogenesis and tumor growth in several preclinical and clinical studies is demonstrated using a vaccination strategy against extracellular vimentin. Targeting vimentin induces a pro-inflammatory condition in the tumor, exemplified by induction of the endothelial adhesion molecule ICAM1, suppression of PD-L1, and altered immune cell profiles. Our findings show that extracellular vimentin contributes to immune suppression and functions as a vascular immune checkpoint molecule. Targeting of extracellular vimentin presents therefore an anti-angiogenic immunotherapy strategy against cancer.

Synthesis of Novel Glycolipid Mimetics of Heparan Sulfate and Their Application in Colorectal Cancer Treatment in a Mouse Model.

Heparan sulfate (HS) is a highly sulfated natural carbohydrate that plays crucial roles in cancer, inflammation, and angiogenesis. Heparanase (HPSE) is the sole HS degrading endoglycosidase that cleaves HS at structure‐dependent sites along the polysaccharide chain. Overexpression of HPSE by cancer cells correlates with increased tumor size and enhanced metastasis. Previously we have shown that a tetramer HS mimetic is a potent HPSE inhibitor displaying remarkable anticancer activity in vivo. Building on that work, we report the synthesis and testing of a novel library of single entity trimer glycolipid mimetics that effectively inhibit HPSE at low nanomolar concentrations. A lipophilic arm was introduced to assess whether an improvement of pharmacokinetics and plasma residence time would offset the reduction in charge and multivalency. Preclinical tests in a mouse syngeneic model showed effective tumor growth inhibition by the tetramer but not the trimer glycomimetic.

Combined Treatment with Ultrasound and Immune Checkpoint Inhibitors for Prostate Cancer.

Background: Ultrasound (US) is mostly used for diagnostic purpose but could be used for cancer treatments with a US intensity or frequency fitted to such a purpose. Prostate cancer (PC) has the highest prevalence in the urological field, but indications for immune checkpoint inhibitors (ICIs) for PC are limited to very few cases. In this study, we compared the antitumor effect of US irradiation alone with the combined use of US and ICIs in vitro and in vivo. Methods: PC cell line TRAMP-C2 cells were used in our experiments. TRAMP-C2 cells were irradiated with US with pulse repeated frequencies (PRF) of 1, 10, and 100 Hz. Cell proliferation was evaluated by MTS assay and apoptotic cells were analyzed using flow cytometry. To verify the antitumor effect of US irradiation on PC in vivo, we conducted animal experiments using mice. TRAMP-C2-bearing mice were irradiated with US with PRF of 10 and 100 Hz. Three weeks after the start of US irradiation, anti-PD-1 antibody was administered to the mice. Finally, mice were sacrificed and tumors were collected. Immunohistochemical (IHC) analyses were assessed for cleaved caspase-3 and CD3 in tumor cell extracts. Results: Cell proliferation assays showed that 1 and 10 Hz US significantly inhibited cell survival (p < 0.0001). In addition, US irradiation induced apoptosis at 1, 10, and 100 Hz (p = 0.0129, p = 0.0150, and p = 0.0017, respectively). In animal experiments, a significant tumor growth inhibitory effect was observed at 10 and 100 Hz, and 100 Hz + ICIs (p < 0.05, respectively). Hematoxylin–eosin (H–E) staining showed a significant increase in the necrotic area of the tumor at 100 Hz and 100 Hz + ICIs (p < 0.05, respectively). In addition, under IHC staining the expression level of cleaved caspase-3 and the number of CD3-positive cells increased at 100 Hz (p < 0.05, respectively). Conclusion: US irradiation induced apoptosis in cells and reduced cell viability. In vivo tumor growth was suppressed by combined treatment with US irradiation and ICIs. Further research on immune system activation will lead to less invasive and more efficient treatments for PC.

(+)-Cyanidan-3-ol inhibits epidermoid squamous cell carcinoma growth via inhibiting AKT/mTOR signaling through modulating CIP2A-PP2A axis

Background: Despite recent advances in the treatment of squamous cell skin cancer (SCSC), the disease persists, and treatment resistance develops. Thus, identifying new targets and developing new therapeutic approaches showing low vulnerability to drug resistance is highly needed.Purpose: This study aimed to reveal a novel targeted phytotherapeutic strategy for SCSC treatment alone or in combination with standard targeted anticancer molecules.Study design: A library of natural products was utilized to identify molecules that inhibit the growth of skin cancer cells. The anticancer potential of the selected compound was evaluated in human skin squamous carcinoma models, in vitro and in vivo. A comprehensive ingenuity pathway analysis (IPA) strategy and molecular biology technology was adopted to investigate the therapeutic mechanisms in human SCSC.Methods: The Matrigel invasion chamber, foci formation and soft agar colony formation assays were employed to study the cells invasion and migration potential in vitro. In vivo antitumor effects were evaluated in DMBA/TPA-induced skin papilloma and A431 human skin squamous carcinoma xenograft tumor models. An integrative IPA was employed to identify mechanisms and protein targets in human SCSC.Compounds synergies were determined by the bliss model and evaluated using human SCSC cell lines and xenograft tumors. Histological staining, immunofluorescence imaging, real-time PCR, Western blots, and flow cytometric analyses were employed to analyze apoptosis and cell signaling mechanisms.Results: We identified (+)-cyanidan-3-ol (CD-3) as a selective compound for inhibiting the growth of SCSC cell lines. CD-3 inhibited tumor growth and burden without apparent toxicity and prolonged the survival of tumor-bearing mice. CD-3 inhibitory effects on SCSC growth are mediated via cell cycle arrest and caspase-dependent apoptosis induction. Mechanistic studies showed that CD-3 activates PP2A via inhibiting CIP2A and produces tumor growth inhibitory effects via promoting dephosphorylation of oncogenic AKT/mTOR signaling proteins in SCSC cells and xenograft tumors in a PP2A dependent manner. Furthermore, the combination of CD-3 and mTOR inhibitors (mTORi) synergistically reduced oncogenic phenotypes.Conclusions: Our study suggests that PP2A activation is an effective strategy for SCSC treatment and the CD-3 and mTORi combination may serve as a promising treatment for SCSC.

Molecular docking and optical sensor studies based on 2,4-diamino pyrimidine-5-carbonitriles for detection of Hg2+

An organic chemical sensor based on pyrimidine was successfully produced through the green reaction between aromatic aldehyde, malononitrile, and guanidine carbonate using SBA-Pr-SO3H. This fluorescence intensity of chemosensor (2,4-diamino-6-(phenyl)pyrimidine-5-carbonitrile) decreases by the addition of Hg2+ and its detection limit is about 14.89 × 10−5 M, in fact, through the green synthesis, the ligand was yielded to detect Hg2+ and the importance of ligand was considered in docking studies. The molecular docking of 2,4-diamino-6-(phenyl)pyrimidine-5-carbonitrile compound has been done with the protein selective estrogen receptor 5ACC complexed with (Azd9496), Human Anaplastic Lymphoma Kinase Pdb; 2xp2 complex with crizotinib (PF-02341066) and human wee1 kinase Pdb; 5vc3 complexed with bosutinib. The ligands 2,4-diamino-6-(phenyl)pyrimidine-5-carbonitrile generate very good docking results with the protein Pdb; 2xp2, which is responsible for effective tumor growth inhibition.

Integrated Design of a Membrane-Lytic Peptide-Based Intravenous Nanotherapeutic Suppresses Triple-Negative Breast Cancer.

Membrane‐lytic peptides offer broad synthetic flexibilities and design potential to the arsenal of anticancer therapeutics, which can be limited by cytotoxicity to noncancerous cells and induction of drug resistance via stress‐induced mutagenesis. Despite continued research efforts on membrane‐perforating peptides for antimicrobial applications, success in anticancer peptide therapeutics remains elusive given the muted distinction between cancerous and normal cell membranes and the challenge of peptide degradation and neutralization upon intravenous delivery. Using triple‐negative breast cancer as a model, the authors report the development of a new class of anticancer peptides. Through function‐conserving mutations, the authors achieved cancer cell selective membrane perforation, with leads exhibiting a 200‐fold selectivity over non‐cancerogenic cells and superior cytotoxicity over doxorubicin against breast cancer tumorspheres. Upon continuous exposure to the anticancer peptides at growth‐arresting concentrations, cancer cells do not exhibit resistance phenotype, frequently observed under chemotherapeutic treatment. The authors further demonstrate efficient encapsulation of the anticancer peptides in 20 nm polymeric nanocarriers, which possess high tolerability and lead to effective tumor growth inhibition in a mouse model of MDA‐MB‐231 triple‐negative breast cancer. This work demonstrates a multidisciplinary approach for enabling translationally relevant membrane‐lytic peptides in oncology, opening up a vast chemical repertoire to the arms race against cancer.

A silica-based antioxidant nanoparticle for oral delivery of Camptothecin which reduces intestinal side effects while improving drug efficacy for colon cancer treatment

Camptothecin (CPT) is a potent anticancer agent for the treatment of colorectal cancer; however, it exhibits some limitations, including poor solubility, low stability, and low bioavailability via oral administration, which restrict its usability in clinical treatments. In addition, overproduction of reactive oxygen species (ROS) during chemotherapy induces drug resistance and severe intestinal side effects. In this study, silica-installed ROS scavenging nanoparticles (siRNP) with 50–60 nm in diameter were employed to overcome the aforementioned drawbacks of CPT. The solubility of CPT was significantly improved by incorporating it into the core of the nanoparticle, forming CPT-loaded siRNP (CPT@siRNP). The anticancer activity of CPT@siRNP against colorectal cancer cells (C-26) in vitro was significantly improved as compared to free CPT through higher efficiency of intracellular internalization and induction of apoptosis. Owing to its antioxidant properties, CPT@siRNP reduced cytotoxicity to normal endothelial cells, which was in sharp contrast to the high toxicity of free CPT. Oral administration of CPT and CPT@siRNP to the C-26 tumor-bearing mice exhibited antitumor activity, accompanied by effective suppression of tumor growth. Although CPT treatment suppressed tumor progression, it caused severe side effects, including intestinal damage and significant bodyweight loss. Interestingly, such noticeable side effects were not observed in the mice treated with CPT@siRNP, and the effect of tumor growth inhibition tended to be similar to or higher than that of CPT treatment. The results obtained in this study indicate that CPT@siRNP is a potential therapeutic nanomedicine for the treatment of colon cancer. Statement of significanceHere we employed silica-containing antioxidant nanoparticle (siRNP) as promising oral delivery nanocarrier of campothecin (CPT) to treat colon cancer. The design of siRNP via covalent conjugation of antioxidant nitroxide radicals and the silanol groups in the polymer backbone contributes to a significant increase in the absorption of hydrophobic drug molecules inside the core and enhances the stability of nanoparticles in the gastrointestinal environment for oral drug delivery. CPT-loaded siRNP (CPT@siRNP) significantly improved solubility of CPT. As compared to free CTP, the CPT@siRNP treatment showed a significantly higher toxicity to colon cancer cell, inhibition of cancer cell migration, and induction of apopotosis. With the antioxidant feature, siRNP also significantly suppressed the intestinal side effects caused by CPT treatment in tumor-bearing mouse model.

Inhibition of cIAP1 in the effective suppression of chemotherapy‑resistant hepatoblastoma.

Cellular inhibitor of apoptosis protein‑1 (cIAP1) is a key regulator of programmed cell death and is known to be associated with chemotherapeutic resistance. The present study aimed to investigate the antitumor efficacy of birinapant, a novel selective inhibitor of cIAP1, against cisplatin (CDDP)‑resistant hepatoblastoma (HB) cells. Western blot analysis was used to investigate the antitumor effect of birinapant on cIAP1 expression in Huh6 cells at the protein level. A WST‑8 assay was performed to evaluate the tumor growth inhibitory effect of birinapant on the human HB cell lines, Huh6 and HepG2. Huh6 cells were exposed to CDDP and/or birinapant in order to confirm tumor growth inhibition. The antitumor efficacy of birinapant plus CDDP combination therapy was significantly higher than that of CDDP monotherapy in a dose‑dependent manner (P=0.035). The study also investigated the antitumor efficacy of birinapant plus CDDP combination therapy in an established xenograft model of SCID mice. Compared with CDDP monotherapy, birinapant combined with CDDP showed better inhibition of tumor growth (P=0.121). It was observed that the mRNA expression of cIAP1 in tumors was significantly enriched in the CDDP monotherapy group compared with that in the untreated group. Furthermore, immunohistochemical staining was performed to compare cIAP1 expression in pre‑ and post‑chemotherapy specimens in patients with HB, and a significant increase was observed in the post‑chemotherapy specimens (P<0.001). CDDP‑resistant Huh6 (Huh6‑CDDPR) cells were also established following repeated exposure to CDDP. Birinapant was substantially more effective against the Huh6‑CDDPR cells than against the Huh6 wild‑type cells. Taken together, these findings suggest that repeated exposure to CDDP enhances cIAP1 expression in HB cells and that birinapant is a promising therapeutic drug for CDDP‑resistant HB.

Outcomes of anlotinib plus nab-paclitaxel/gemcitabine as first-line treatment for patients with advanced pancreatic adenocarcinoma: A retrospective analysis in China.

556 Background: Anlotinib, a novel small molecule multi-target tyrosine kinase inhibitor that can effectively inhibit VEGFR, PDGFR, FGFR, C-KIT et al, is proved to have anti-tumor angiogenesis and tumor growth inhibition effects. However, Anlotinib exploration on advanced pancreatic adenocarcinoma (PDAC) is still limited. The motivation of this work is to evaluate the efficacy and safety of anlotinib combined with nab-paclitaxel/gemcitabine in the first-line treatment of patients with advanced PDAC, and provide some evidence for the treatment regimens of advanced PDAC. Methods: This was a retrospective study in patients with advanced PDAC performed from Aug 17, 2019 to Apr 3, 2021. Patients who received anlotinib plus nab-paclitaxel/gemcitabine treatment were defined as Group 1, and patients who received nab-paclitaxel/gemcitabine as Group 2. The study was approved by the Ethics Committee of the First Affiliated Hospital of Anhui Medical University (P2021-13-21). The response to treatment was evaluated according to RECIST version 1.1. In addition, adverse events were evaluated by CTCAE v5.0. Results: In this work, 33 patients were included, with 17 cases in Group 1 and 16 cases in Group 2. The median PFS (mPFS) of Group 1 and Group 2 were 5.0 (95% Cl, 4.97-5.94) months and 2.7 (95% Cl, 2.4-3.3) months, respectively ( P = 0.0220). The median OS (mOS) of Group 1 and Group 2 were 9.0 (95% Cl, 6.55-11.45) months and 6.0 (95% Cl, 1.08-10.92) months, respectively ( P=0.006). The PFS rate in 3 and 6 months and the OS rate in 6 and 12 months of Group 1 were significantly higher than that of Group 2. The most common grade 3 treatment related AEs (trAEs) were hematological toxicity, with 35.29% in Group1 and 31.25% in Group 2. Non-hematological toxicity were hypertension, hand-foot syndrome and diarrhea. No grade 3 or higher non-hematologic toxicity was observed in all patients. Conclusions: Anlotinib plus nab-paclitaxel/gemcitabine as first-line treatment demonstrates encouraging efficacy and manageable AE in patients with advanced PDAC. Clinical outcomes are improved with longer PFS and OS in anlotinib plus chemotherapy group. More data are needed to confirm the long-term efficacy and safety of anlotinib plus nab-paclitaxel/gemcitabine in advanced PDAC patients.