Non-IL-2-blocking anti-CD25 antibody inhibits tumor growth by depleting Tregs and has synergistic effects with anti-CTLA-4 therapy.

CD25, also known as the interleukin-2 receptor α chain (IL-2Rα), is highly expressed on regulatory T cells (Tregs), but relatively lower on effector T cells (Teffs). This makes it a potential target for Treg depletion, which can be used in tumor immunotherapy. However, marketed anti-CD25 antibodies (Basiliximab and Daclizumab) were originally developed as immunosuppressive drugs to prevent graft rejection, because these antibodies can block IL-2 binding to CD25 on Teffs, which in turn destroys the function of Teffs. Recent studies have shown that non-IL-2-blocking anti-CD25 antibodies have displayed exciting antitumor effects. Here, we screened out a non-IL-2-blocking anti-CD25 monoclonal antibody (mAb) 7B7 by hybridoma technology, and confirmed its antitumor activity via depleting Tregs in a CD25 humanized mouse model. Subsequently, we verified that the humanized 7B7, named as h7B7-15S, has comparable activities to 7B7, and that its Treg depletion is further increased when combined with anti-CTLA-4, leading to enhanced remodeling of the tumor immune microenvironment. Moreover, our findings reveal that the Fab form of h7B7-15S has the ability to deplete Tregs, independent of the Fc region. Taken together, our studies expand the application of anti-CD25 in tumor immunotherapy and provide insight into the underlying mechanism.

Antibody-drug conjugates: Recent advances in payloads.

Antibody‒drug conjugates (ADCs), which combine the advantages of monoclonal antibodies with precise targeting and payloads with efficient killing, show great clinical therapeutic value. The ADCs' payloads play a key role in determining the efficacy of ADC drugs and thus have attracted great attention in the field. An ideal ADC payload should possess sufficient toxicity, low immunogenicity, high stability, and modifiable functional groups. Common ADC payloads include tubulin inhibitors and DNA damaging agents, with tubulin inhibitors accounting for more than half of the ADC drugs in clinical development. However, due to clinical limitations of traditional ADC payloads, such as inadequate efficacy and the development of acquired drug resistance, novel highly efficient payloads with diverse targets and reduced side effects are being developed. This perspective summarizes the recent research advances of traditional and novel ADC payloads with main focuses on the structure-activity relationship studies, co-crystal structures, and designing strategies, and further discusses the future research directions of ADC payloads. This review also aims to provide valuable references and future directions for the development of novel ADC payloads that will have high efficacy, low toxicity, adequate stability, and abilities to overcome drug resistance.

FTL004, an anti-CD38 mAb with negligible RBC binding and enhanced pro-apoptotic activity, is a novel candidate for treatments of multiple myeloma and non-Hodgkin lymphoma.

Anti-CD38 monoclonal antibodies (mAbs), daratumumab, and isatuximab have represented a breakthrough in the treatment of multiple myeloma (MM). Recently, CD38-based mAbs were expected to achieve increasing potential beyond MM, which encouraged us to develop new anti-CD38 mAbs to meet clinical needs. In this study, we developed a novel humanized anti-CD38 antibody, FTL004, which exhibited enhanced pro-apoptotic ability and negligible binding to red blood cells (RBCs). FTL004 presented a better ability to induce direct apoptosis independent of Fc-mediated cross-linking against lymphoma and MM cell lines as well as primary myeloma cells derived from MM patients. For instance, FTL004 induced RPMI 8226 cells with 55% early apoptosis cells compared with 20% in the isatuximab-treated group. Of interest, FTL004 showed ignorable binding to CD38 on human RBCs in contrast to tumor cells, even at concentrations up to 30 µg/mL. Furthermore, with an engineered Fc domain, FTL004 displayed stronger antibody-dependent cellular cytotoxicity (ADCC) against CD38+ malignant cells. In vivo MM and non-Hodgkin lymphoma tumor xenograft models showed that FTL004 possessed an effective anti-tumor effect. Cryo-electron microscopy structure resolved two epitope centers of FTL004 on CD38: one of which was unique while the other partly overlapped with that of isatuximab. Taken together, FTL004 distinguishes it from other CD38 targeting mAbs and represents a potential candidate for the treatment of MM and non-Hodgkin lymphoma.

Design, Synthesis, and Bioevaluation of a Novel Hybrid Molecular Pyrrolobenzodiazepine-Anthracenecarboxyimide as a Payload for Antibody-Drug Conjugate.

A novel series of hybrid molecules combining pyrrolobenzodiazepine (PBD) and anthracenecarboxyimide pharmacophores were designed, synthesized, and tested for in vitro cytotoxicity against various cancer cell lines. The most potent compound from this series, 37b3, exhibited a subnanomolar level of cytotoxicity with an IC50 of 0.17-0.94 nM. 37b3 induced DNA damage and led to tumor cell cycle arrest and apoptosis. We employed 37b3 as a payload to conjugate with trastuzumab to obtain the antibody-drug conjugate (ADC) T-PBA. T-PBA maintained its mode of target and internalization ability of trastuzumab. We demonstrated that T-PBA could be degraded through the lysosomal pathway to release the payload 37b3 after internalization. T-PBA showed a powerful killing effect on Her2-positive cancer cells in vitro. Furthermore, T-PBA significantly inhibited tumor growth in gastric and ovarian cancer xenograft mouse models without overt toxicity. Collectively, these studies suggest that T-PBA represents a promising new ADC that deserves further investigation.

Combination Foretinib and Anti-PD-1 Antibody Immunotherapy for Colorectal Carcinoma.

Immune checkpoint inhibitors have achieved unprecedented success in cancer immunotherapy. However, the overall response rate to immune checkpoint inhibitor therapy for many cancers is only between 20 and 40%, and even less for colorectal cancer (CRC) patients. Thus, there is an urgent need to develop an efficient immunotherapeutic strategy for CRC. Here, we developed a novel CRC combination therapy consisting of a multiple receptor tyrosine kinase inhibitor (Foretinib) and anti-PD-1 antibody. The combination therapy significantly inhibited tumor growth in mice, led to improved tumor regression without relapse (83% for CT26 tumors and 50% for MC38 tumors) and prolonged overall survival. Mechanistically, Foretinib caused increased levels of PD-L1 via activating the JAK2-STAT1 pathway, which could improve the effectiveness of the immune checkpoint inhibitor. Moreover, the combination therapy remodeled the tumor microenvironment and enhanced anti-tumor immunity by further increasing the infiltration and improving the function of T cells, decreasing the percentage of tumor-associated macrophages (TAMs) and inhibiting their polarization toward the M2 phenotype. Furthermore, the combination therapy inhibited the metastasis of CT26-Luc tumors to the lung in BALB/c mouse by reducing proportions of regulatory T-cells, TAMs and M2 phenotype TAMs in their lungs. This study suggests that a novel combination therapy utilizing both Foretinib and anti-PD-1 antibody could be an effective combination strategy for CRC immunotherapy.

Opportunities and obstacles of targeted therapy and immunotherapy in small cell lung cancer.

Small cell lung cancer (SCLC) is an aggressive malignant tumour which accounts for approximately 13-15% of all newly diagnosed lung cancer cases. To date, platinum-based chemotherapy are still the first-line treatments for SCLC. However, chemotherapy resistance and systemic toxicity limit the long-term clinical outcome of first-line treatment in SCLC. Recent years, targeted therapy and immunotherapy have made great breakthrough in cancer therapy, and researchers aim to exploit both as a single agent or in combination with chemotherapy to improve the survival of SCLC patients, but limited effectiveness and the adverse events remain the major obstacles in the treatment of SCLC. To overcome these challenges for SCLC therapies, prevention and early diagnosis for this refractory disease is very important. At the same time, we should reveal more information about the pathogenesis of SCLC and the mechanism of drug resistance. Finally, new treatment strategies should also be taken into considerations, such as repurposing drug, optimising of targets, combination therapy strategies or prognostic biomarkers to enhance therapeutic effects and decrease the adverse events rates in SCLC patients. This article will review the molecular biology characteristics of SCLC and discuss the opportunities and obstacles of the current therapy for SCLC patients.

HeLa Cell-Derived Paclitaxel-Loaded Microparticles Efficiently Inhibit the Growth of Cervical Carcinoma.

AIM: Tumor cell-derived microparticles (MP) can function as a targeted delivery carrier for anti-tumor drugs. Here, we aimed to generate paclitaxel-loaded microparticles (MP-PTX) from HeLa cells and examined its therapeutic potential on human cervical carcinoma. METHODS: MP-PTX was generated from HeLa cells by ultraviolet radiation and subsequent centrifugation. The particle size, drug loading rate, and stability of MP-PTX were examined in vitro. Flow cytometry and the MTT assay were performed to test the inhibitory effect of MP-PTX using different cell lines. Immunodeficient mice bearing HeLa cervical carcinoma were treated with 0.9% normal saline, MP, paclitaxel (PTX) (2.5 mg/kg), or MP-PTX (PTX content identical to PTX group) every day for 6 consecutive days. Tumor volume and animal survival were observed. Micro 18F-FDG PET/CT was performed to monitor the therapeutic efficacy. The proliferation activity of cells and microvessel density in tumor tissues were determined by immunohistochemical staining using Ki-67 and CD31, respectively. RESULTS: Dynamic laser scattering measurements showed that the particle size of MP-PTX was 285.58 ± 2.95 nm and the polydispersity index was 0.104 ± 0.106. And the particle size of MP-PTX was not change at 4°C for at least one week. More than 1% of PTX in the medium could be successfully encapsulated into HeLa cell-derived MP. When compared with PTX, MP-PTX treatment significantly increased apoptosis of tumor cells and reduced their proliferation. In addition, MP-PTX showed lower toxicity to normal human umbilical vein endothelial cells (HUVEC) than PTX. In vivo studies further demonstrated that MP-PTX treatment significantly inhibited the growth of cervical carcinoma, prolonged the survival of tumor-bearing mice, and reduced the toxicity of PTX. Immunohistochemical staining revealed that MP-PTX treatment led to decreased Ki-67 positive tumor cells and decreased microvessel density in tumor tissues. CONCLUSION: Our results demonstrated that HeLa-derived MP-PTX significantly enhanced the anti-cancer effects of PTX with reduced toxicity, which may provide a novel strategy for the treatment of cervical carcinoma.

Cryptophycin-55/52 based antibody-drug conjugates: Synthesis, efficacy, and mode of action studies.

Cryptophycin-52 (CR52), a tubulin inhibitor, exhibits promising antitumor activity in vitro (picomolar level) and in mouse xenograft models. However, the narrow therapeutic window in clinical trials limits its further development. Antibody-drug conjugate (ADC), formed by coupling cytotoxic compound (payload) to an antibody via a linker, can deliver drug to tumor locations in a targeted manner by antibody, enhancing the therapeutic effects and reducing toxic and side effects. In this study, we aim to explore the possibility of CR52-based ADC for tumor targeted therapy. Due to the lack of a coupling site in CR52, its prodrug cryptophycin-55 (CR55) containing a free hydroxyl was synthesized and conjugated to the model antibody trastuzumab (anti-HER2 antibody drug approved by FDA for breast cancer therapy) via the linkers based on Mc-NHS and Mc-Val-Cit-PAB-PNP. The average drug-to-antibody ratios (DARs) of trastuzumab-CR55 conjugates (named T-L1-CR55, T-L2-CR55, and T-L3-CR55) were 3.50, 3.29, and 3.35, respectively. These conjugates exhibited potent cytotoxicity in HER2-positive tumor cell lines with IC50 values at low nanomolar levels (0.58-1.19 nM). Further, they displayed significant antitumor activities at the doses of 10 mg/kg in established ovarian cancer (SKOV3) and gastric cancer (NCI-N87) xenograft models without overt toxicities. Finally, the drug releases were analyzed and the results indicated that T-L3-CR55 was able to effectively release CR55 and further epoxidized to CR52, which may be responsible for its best performance in antitumor activities. In conclusion, our results demonstrated that these conjugates have the potential for tumor targeted therapy, which provides insights to further research the CR55/CR52-based ADC for tumor therapy.

Effective antitumor activity of 5T4-specific CAR-T cells against ovarian cancer cells in vitro and xenotransplanted tumors in vivo.

Ovarian cancer is considered to be the most lethal gynecologic malignancy, and despite the development of conventional therapies and new therapeutic approaches, the patient's survival time remains short because of tumor recurrence and metastasis. Therefore, effective methods to control tumor progression are urgently needed. The oncofetal tumor-associated antigen 5T4 (trophoblast glycoprotein, TPBG) represents an appealing target for adoptive T-cell immunotherapy as it is highly expressed on the surface of various tumor cells, has very limited expression in normal tissues, and spreads widely in malignant tumors throughout their development. In this study, we generated second-generation human chimeric antigen receptor (CAR) T cells with redirected specificity to 5T4 (5T4 CAR-T) and demonstrated that these CAR-T cells can elicit lytic cytotoxicity in targeted tumor cells, in addition to the secretion of cytotoxic cytokines, including IFN-γ, IL-2, and GM-CSF. Furthermore, adoptive transfer of 5T4 CAR-T cells significantly delayed tumor formation in xenografts of peritoneal and subcutaneous animal models. These results demonstrate the potential efficacy and feasibility of 5T4 CAR-T cell immunotherapy and provide a theoretical basis for the clinical study of future immunotherapies targeting 5T4 for ovarian cancer.

Targeting of DDR1 with antibody-drug conjugates has antitumor effects in a mouse model of colon carcinoma.

DDR1 has been identified as a cancer-associated receptor tyrosine kinase that is highly expressed in several malignancies relative to normal tissues. Clinically approved multi-kinase inhibitors, such as nilotinib, inhibit DDR1-mediated tumor growth in xenograft models, suggesting DDR1 might be a potential target for cancer treatments. Here, we employed an antibody-based strategy with a novel anti-DDR1 antibody-drug conjugate (ADC) for colon carcinoma treatment. We developed T4 H11 -DM4, an ADC targeting DDR1 which carries the tubulin inhibitor payload DM4. Immunohistochemical analysis of a tissue microarray containing 100 colon cancer specimens revealed that DDR1 was highly expressed in 81% of tumor tissues. Meanwhile, high expression of DDR1 was associated with poor survival in patients. In vitro, T4 H11 -DM4 exhibited potent anti-proliferative activity with half maximal inhibitory concentration (IC50 ) values in the nanomolar range in a panel of colon cancer cell lines. In vivo, the antitumor efficacy of T4 H11 -DM4 was evaluated in three colon cancer cell lines expressing different levels of DDR1. T4 H11 -DM4 achieved complete tumor regression at doses of 5 and 10 mg·kg-1 in HT-29 and HCT116 tumor models. Moreover, a correlation between in vivo efficacy of T4 H11 -DM4 and the levels of DDR1 expression on the cell surface was observed. Tumor cell proliferation was caused by the induction of mitotic arrest, indicating that the antitumor effect in vivo was mediated by DM4. In addition, T4 H11 -DM4 was efficacious in oxaliplatin-resistant colon cancer models. In exploratory safety studies, T4 H11 -DM4 exhibited no overt toxicities when multi-doses were administered at 10 mg·kg-1 into BALB/c nude mice or when a single dose up to 50 mg·kg-1 was administered into BALB/c mice. Overall, our findings highlight the potential of DDR1-targeted ADC and may facilitate the development of a new effective therapeutic strategy for colon cancer.

Expression of 5T4 extracellular domain fusion protein and preparation of anti-5T4 monoclonal antibody with high affinity and internalization efficiency.

5T4, a membrane protein, is overexpressed in many tumor tissues but rarely expressed in normal tissues. Here, CHO-5T4+ cells were generated and served as the antigen to immunize mice. Hybridoma techniques were employed to produce monoclonal antibodies (mAbs). The recombinant protein of human IgG Fc-fused extracellular domain of 5T4 (5T4 ECD-Fc) was obtained from transient expression in HEK293F cells. The fusion protein 5T4 ECD-Fc and CHO-5T4+ cells were respectively utilized to screen anti-5T4 antibodies that could bind to the native antigen. In preliminary screening, three hundred and fifty mAbs were obtained. Via surface plasmon resonance and flow cytometry screening, seven anti-5T4 mAbs stood out. Among them, H6 showed a high affinity (KD = 1.6 × 10-11 M) and internalization percentage (36% for 1 h and 80% for 4 h). The molecular weight and isoelectric point of H6 were determined by LC-MS and iCIEF. Moreover, the specific reactivity of H6 was demonstrated by western blotting, flow cytometry, and immunohistochemistry, respectively. In conclusion, we produced human recombinant protein of 5T4 extracellular domain and developed high-affinity internalizing monoclonal antibodies which may be applied in the 5T4-targeting ADC therapy and basic research.

Design, synthesis and biological evaluation of a novel tubulin inhibitor 7a3 targeting the colchicine binding site.

Tubulin inhibitors that target the colchicine binding site continue to emerge as promising anticancer agents. In this study, based on the anti-proliferative activities, a novel tubulin inhibitor 7a3 targeting the colchicine binding site was designed, synthesized, and optimized from a series of novel cis-restricted pyrazole analogues of combretastatin A-4. The structure-activity relationships (SARs) of these newly synthesized compounds are summarized indicating that the methyl substituent at the N1 position and deamination were significantly important for the anti-proliferative efficacy. The optimized compound 7a3 exhibited the ability to arrest the cell cycle in the G2/M phase, induce cell apoptosis, and inhibit cell migration in tumour cells. The results of the immunofluorescence analysis using confocal microscopy and the tubulin polymerization assay revealed that tubulin assembly was disrupted by 7a3 in vitro. Furthermore, the targeting identification of 7a3 was illuminated by solving the crystal structure of 7a3 in complex with tubulin at a resolution of 3.2 Š(PDB code 5Z4U), which confirmed the result of molecular docking and further demonstrated that 7a3 binds to the site of colchicine. Moreover, the pharmacokinetic analysis in mouse plasma showed that 7a3 rapidly reached a peak concentration at 0.25 h after intraperitoneal administration, and the T1/2, Cmax, and AUC0-inf were 1.67 ±â€¯0.28 h, 882 ±â€¯71 ng mL-1, and 1166 ±â€¯129 h ng·mL-1, respectively, after a single-dose administration analysed by liquid chromatography-tandem mass spectrometry (LC/MS/MS). In addition, the in vivo study indicated that 7a3 significantly inhibited the tumour growth of the SK-OV-3 xenograft in a nude mouse model. In conclusion, our study proved 7a3 to be a potential microtubule-targeting drug for cancer therapy. The SARs and mechanism of action studies of 7a3 based on the X-ray co-crystal structure provided insights into the next-generation tubulin inhibitors for cancer therapy.

A novel 5T4-targeting antibody-drug conjugate H6-DM4 exhibits potent therapeutic efficacy in gastrointestinal tumor xenograft models.

5T4, also named as trophoblast glycoprotein, is often upregulated in some cancer cells. Here, we demonstrated that 5T4 was highly expressed in gastric, colorectal, and pancreatic cancer, associated with significantly poor prognosis of gastrointestinal (GI) cancer patients. To search for new targeting drugs for GI cancer, we developed a novel anti-5T4 monoclonal antibody with high affinity and robust internalization ability and conjugated it to the potent microtubule inhibitor DM4 to produce conjugate H6-DM4. This antibody-drug conjugate (ADC) displayed significant cytotoxicity in a panel of GI cancer cell lines with IC50 values in the nanomolar range. H6-DM4 eradicated established GI tumor xenograft models at 2.5 mg/kg or 10 mg/kg without observable toxicity. Further, 5T4 was highly expressed in cancer-initiating cells (CICs) compared with non-CICs in colorectal cancer. In vitro and in vivo, treatment with H6-DM4 exhibited a powerful efficacy on colorectal CICs. Additionally, colorectal cancer cells resistant to platinum were effectively eliminated by H6-DM4. Taken together, our results showed 5T4-positive GI cancer cells, colorectal cancer-initiating cells, and platinum-resistant colorectal cancer cells were potently eliminated by H6-DM4, indicating H6-DM4 may be a potential candidate drug for GI cancer treatment.

Preparation and anti-cancer evaluation of promiximab-MMAE, an anti-CD56 antibody drug conjugate, in small cell lung cancer cell line xenograft models.

Antibody-drug conjugates (ADCs) have been successfully applied clinically as target drugs for cancer. In this study, anti-neural cell adhesion molecule also called CD56 antibody-monomethyl auristatin E (MMAE) conjugate named Promiximab-MMAE was prepared by conjugation of microtubule inhibitor MMAE with Promiximab. The average drug-to-antibody ratio (DAR) of Promiximab-MMAE was 3.13 as analysed by liquid chromatography-mass spectrometry/ mass spectrometry (LC-MS/MS). The targeting capacity and affinity kinetics of Promiximab-MMAE were similar to that of Promiximab after being conjugated with MMAE as tested by flow cytometry and biolayer interferometry analysis. Promiximab-MMAE showed effective anti-proliferation on CD56-positive cell lines (NCI-H524, NCI-H526, and NCI-H69), with the half maximal inhibitory concentration (IC50) values of 19.24, 5.23, and 0.32 nmol/L in vitro, respectively. Promiximab-MMAE of 10 mg/kg every three days with a total of three times was administered in vivo. Results showed that the tumour regression was not recrudesced in NCI-H69 and NCI-H526 xenograft mice models till 52 and 56 days. Moreover, body weight and histopathology of the major organs (liver, spleen, heart, lung, and kidney) showed no significant changes after treatment with Promiximab-MMAE. In conclusion, Promiximab-MMAE is a potential candidate for the treatment of CD56 positive small cell lung cancer.

Promiximab-duocarmycin, a new CD56 antibody-drug conjugates, is highly efficacious in small cell lung cancer xenograft models.

Small cell lung cancer (SCLC) is of a highly invasive and metastatic lung cancer subtype and there had not been effective targeted therapies. CD56, a cell surface marker highly expressed on most SCLC, is a promising therapeutic target for treatment of this aggressive cancer. In this study, we generated a novel anti-CD56 antibody named promiximab, characterized by high affinity, internalization and tumor specificity. Then, the promiximab was conjugated with a potent DNA alkylating agent duocarmycin via reduced interchain disulfides to yield the promiximab-Duocarmycin (promiximab-DUBA) conjugates. Mass spectrometry analysis showed promiximab-DUBA had an average DAR (Drug-to-Antibody Ratio) of about 2.04. In vitro, promiximab-DUBA exerted strong inhibitory effects on SCLC cell lines NCI-H526, NCI-H524 and NCI-H69, with IC50 values of 0.07 nmol/L, 0.18 nmol/L and 0.29 nmol/L, respectively. In vivo antitumor activity, promiximab-DUBA at the dose of 5 mg/kg and 10 mg/kg every three days with a total of three times were sufficient to induce sustained regression of NCI-H526 tumors over control treatment with promiximab. Mostly, no recurrence was observed until 65 days post treatment with promiximab-DUBA. In the NCI-H69 subcutaneous xenograft model, significant inhibition of tumor growth was also observed following administration of promiximab-DUBA at the dose of 5 mg/kg or 10 mg/kg. Moreover, body weight and histopathology of major organs (liver, spleen, heart, lung and kidney) showed no significant changes after treatment of promiximab-DUBA. In conclusion, promiximab-DUBA is highly efficacious in small cell lung cancer xenograft models, and provides a new immunotherapy approach for SCLC.

Therapeutic potential of an anti-HER2 single chain antibody-DM1 conjugates for the treatment of HER2-positive cancer.

Antibody-drug conjugates (ADCs) take the advantage of monoclonal antibodies to selectively deliver highly potent cytotoxic drugs to tumor cells, which have become a powerful measure for cancer treatment in recent years. To develop a more effective therapy for human epidermal growth factor receptor 2 (HER2)-positive cancer, we explored a novel ADCs composed of anti-HER2 scFv-HSA fusion antibodies conjugates with a potent cytotoxic drug DM1. The resulting ADCs, T-SA1-DM1 and T-SA2-DM1 (drug-to-antibody ratio in the range of 3.2-3.5) displayed efficient inhibition in the growth of HER2-positive tumor cell lines and the half-maximal inhibitory concentration on SKBR-3 and SKOV3 cells were both at the nanomolar levels in vitro. In HER2-positive human ovarian cancer xenograft models, T-SA1-DM1 and T-SA2-DM1 also showed remarkable antitumor activity. Importantly, three out of six mice exhibited complete remission without regrowth in the high-dose group of T-SA1-DM1. On the basis of the analysis of luminescence imaging, anti-HER2 scFv-HSA fusion antibodies, especially T-SA1, showed strong and rapid tumor tissue penetrability and distribution compared with trastuzumab. Collectively, the novel type of ADCs is effective and selective targeting to HER2-positive cancer, and may be a promising antitumor drug candidate for further studies.

Salidroside alleviates cachexia symptoms in mouse models of cancer cachexia via activating mTOR signalling.

BACKGROUND: Cachexia has a devastating impact on survival and quality of life for many cancer patients and contributes to nearly one-third of all cancer deaths; also, it is associated with poor responses to chemotherapy and survival. A better understanding of the underlying mechanisms of cancer-associated cachexia (CAC), coupled with effective therapeutic approaches, will improve management of progressive functional impairment in cancer patients. Salidroside, a phenylpropanoid glycoside in Rhodiola rosea L, has been reported to possess potential anti-fatigue, anti-ageing, and anti-Alzheimer's disease properties. It is widely consumed as a nutritional supplement, but its effects on CAC and the possible mechanism remain a mystery. METHODS: In the murine models of cachexia induced by CT-26 and Lewis lung carcinoma (LLC) tumour, respectively, main features of CAC were determined after treatment of salidroside or chemotherapy. In vitro experiments were performed using murine C2C12 myotubes, which were treated by tumour necrosis factor-α. Levels of several critical muscle-related signal proteins such as mammalian target of rapamycin (mTOR), p-mTOR, and myosin heavy chain (MyHC) were examined using western blot both in vitro and in vivo. RESULTS: In the present study, we showed the exciting effect of salidroside on the treatment of CAC. In CT-26 and LLC models, respectively, salidroside treatment could effectively preserve the tumour-free body weight, decrease loss of adipose and gastrocnemius muscles, alleviate tumour burden, and prolong their survival time. Additionally, in combined chemotherapy, salidroside could synergistically enhance the anti-tumour activity of cisplatin, especially decreased or eliminated chemotherapy-induced cachexia. Further analysis demonstrated that salidroside could significantly increase expression of mTOR, p-mTOR, and MyHC in gastrocnemius muscle. Also, results in vitro showed that salidroside could not only obviously increase mTOR, p-mTOR, and MyHC expression in C2C12 myotubes but also effectively rescue their down-regulation induced by tumour necrosis factor-α. CONCLUSIONS: In the current study, the exciting effect of salidroside on CAC suggested that salidroside supplementation might be a promising approach for a multi-targeted therapy for the treatment of CAC.

Analysis of transcription profile to reveal altered signaling pathways following the overexpression of human desumoylating isopeptidase 2 in pancreatic cancer cells.

Human desumoylating isopeptidase 2 (DESI-2) is a member of the DESI family and contains a conserved PPPDE1 domain. Previous studies have demonstrated that DESI-2 overexpression may induce cell apoptosis. In the present study, differentially expressed genes were analyzed using a transcription microarray in DESI-2 overexpressing PANC-1 pancreatic cancer cells. A total of 45,033 genes were examined by microarray, which identified 1,766 upregulated and 1,643 downregulated genes. A series of altered signaling pathways were analyzed, in which certain essential signaling factors, including retinoid X receptor (RXR), BH3 interacting-domain death agonist, Ras homolog gene family member A (RhoA) and Rho-associated protein kinase, were further investigated at the protein level. The release of cytochrome c and the activation of caspase-3 were also detected by western blot analysis. Immunohistochemistry further revealed the expression features of RXR and RhoA in pancreatic ductal adenocarcinoma tissues with various DESI-2 expression levels. The results serve as a valuable reference for the further elucidation of the functions of DESI-2 in pancreatic cancer.

Isoliquiritigenin prevents the progression of psoriasis-like symptoms by inhibiting NF-κB and proinflammatory cytokines.

UNLABELLED: Isoliquiritigenin (ISL) is an important flavonoid component of licorice and has been reported to possess anti-inflammatory and antioxidant properties, but its exact mechanism of action remains poorly understood. Previously, we demonstrated that ISL could suppress IL-6 expression in multiple myeloma. Here, we further characterized the anti-inflammatory effects of ISL in several psoriasis models, including the keratin 14/vascular endothelial growth factor (VEGF) transgenic mouse, the imiquimod (IMQ)-induced psoriasis-like mouse, and the human keratinocytes HaCaT and NHEK in vitro. We found that ISL ameliorated the inflammatory process in psoriasis models but not in their respective controls. Moreover, the anti-inflammatory effects of ISL were attributed to the suppression of nuclear factor-κB (NF-κB) activity, which consequently resulted in the reduction of pro-inflammation cytokines IL-6 and IL-8 expression. In conclusion, ISL exhibited anti-inflammatory effects in psoriasis models, by downregulating IL-6 and IL-8 via suppression of NF-κB activity, suggesting that ISL might serve as a potential candidate for treatment of psoriasis and other autoimmune inflammatory diseases. KEY MESSAGE: ISL could ameliorate the inflammatory process of psoriasis. ISL could suppress NF-κB and subsequent production of a series of pro-inflammatory cytokines. Dual-inhibitory activity against IL-6 and IL-8 of ISL is implemented via inhibiting NF-κB. ISL exerts no inhibitory effects on normal human keratinocytes or wild-type Balb/c mice, implying its low toxicity and safety.

Synthesis, characterization and targeting chemotherapy for ovarian cancer of trastuzumab-SN-38 conjugates.

Antibody-drug conjugates (ADCs), combining monoclonal antibody with high cytotoxicity chemotherapeutic drug (warhead), have been successfully applied for clinical cancer therapy. Linker technology to select and design linker connecting warhead with antibody, is critical to the success of therapeutic ADCs. In this study, three kinds of linkers were designed to connect SN-38, the bioactive metabolite of the anticancer drug irinotecan (CPT-11), which is 100-1000 times more potent than CPT-11, with the anti-HER2 antibody trastuzumab to prepare three different ADC conjugates (T-SN38 A, B and C). Meanwhile, we compared the anti-ovarian cancer effect of these three T-SN38 conjugates with trastuzumab in vitro and in vivo. Our in vitro results showed that T-SN38 A, B and C (drug-to-antibody ratio, DAR=3.7, 3.2, 3.4) were 2 to 3 times as cytotoxic as SN-38, and the IC50 for these three conjugates on SKOV-3 cell line at 72 h were 5.2 ± 0.3, 4.4 ± 0.7, and 5.1 ± 0.4 nM respectively. In our in vivo studies, T-SN38 conjugates had well targeting ability for tumor tissue and all three of them had much higher anti-ovarian cancer potency than trastuzumab. Among of them, T-SN38 B, which coupled SN-38 with trastuzumab by a carbonate bond, has the best anti-ovarian cancer potency. In conclusion, the novel HER2-targeting ADCs T-SN38 have great potential for HER2-positive ovarian cancer. Moreover, the SN-38-Linkers designed in this study can also be used to connect with other antibodies for the therapy of other cancers.