MUC-1 aptamer targeted superparamagnetic iron oxide nanoparticles for magnetic resonance imaging of pancreatic cancer in vivo and in vitro experiment.

This study aims to explore the ability of magnetic resonance imaging (MRI) in mucin 1 (MUC1) modified superparamagnetic iron oxide nanoparticle (SPION) targeting human pancreatic cancer (PC). The MUC1 target-directed probe was prepared through MUC1 conjugated to SPION using the chemical method to assess its physiochemical characteristics, including hydration diameter, surface charge, and magnetic resonance signal. The cytotoxicity of MUC1-USPION was verified by MTS assay. BxPC-3 was cultured with MUC1-USPION and SPION in different concentrations. The combined condition of the targeted probes and cells were observed through Prussian blue staining. The nude mice model of pancreatic cancer was established to investigate the application of the probe. MRI was performed to determine the intensity of the signal of the transplanted tumor, while immunohistochemistry and Western blot analysis were performed to detect the expression of MUC1 after taking the transplanted tumor specimen. The particle size of the prepared molecular probe was 63.5 ± 3.2 nm, and the surface charge was 10.2 mV. Furthermore, the probe solution could significantly reduce the MRI at T2 , and the magnetic resonance transverse relaxation rate (ΔR2 ) has a linear relationship with the concentration of iron in the solution. The cell viability of MUC1-USPION in different concentrations revealed no statistical difference, according to the MTS assay. In vitro, the MRI demonstrated decreased T2WI signal intensity in both groups, especially the targeting group. In vivo, MUC1 could selectively accumulate in the nude mice model, and significantly reduce the T2 signal strength. In subsequent experiments, the expression of MUC1 was high in pancreatic cancer tissues, but low in normal pancreatic tissues, as determined by immunohistochemistry and Western blot analysis. The prepared samples can be combined with pancreatic cancer tissue specificity by in vivo imaging, providing reliable early in vivo imaging data for disease diagnosis.

Osteopontin Promotes Cell Migration and Invasion, and Inhibits Apoptosis and Autophagy in Colorectal Cancer by activating the p38 MAPK Signaling Pathway.

BACKGROUND: Osteopontin (OPN) is highly expressed in colorectal cancer (CRC) and is associated with disease progression in vivo. High levels of OPN have been demonstrated to predict low survival rates in CRC. Autophagy is a process of self-digestion, which is thought to play a significant role in carcinogenesis. However, the mechanisms of OPN's effects on CRC cell autophagy have not been elucidated. Therefore, we aimed to investigate possible mechanisms of OPN's effects on CRC autophagy. METHODS: HCT116 cell proliferation, apoptosis, and migration and invasion ability were identified by cell counting k¡t-8 assay, flow cytometry, wound healing assay, and transwell chamber invasion assay, respectively. The ratios of proteins LC3-II/LC3-I, P62, and Atg7 were analyzed by Western-blot. Expressions of Beclin-1, Atg4b, Bnip3, and Vps34, both in transcriptional and translational levels, were analyzed and compared by RT-PCR and Western blot. Immunofluorescence and co-focusing experiments were used to investigate the formation of autophagosomes. RESULTS: The results showed that OPN can promote cell proliferation, migration, and invasion, as well as inhibit cell apoptosis. It was also demonstrated that OPN could inhibit cell autophagy. Further experiments revealed that the inhibitory effect of OPN on autophagy could be reversed by blocking the p38 MAPK pathway in HCT116 cells. CONCLUSION: OPN is involved in HCT116 cell progression and is capable of inhibiting cell autophagy possibly by activating the p38 MAPK signaling pathway, implying that OPN could be a potential novel molecular therapeutic biomarker in patients with CRC.

HBx affects CUL4-DDB1 function in both positive and negative manners.

Hepatitis B virus (HBV) infection is a major public health problem by affecting 350 million people worldwide. The mechanisms that regulate HBV gene expression and viral replication remain poorly understood. HBx is known as the central regulator for HBV replication and is associated with the CUL4-DDB1 ubiquitin ligase through H-box motif. Here, we show that blocking the activity of DDB1 by RNA interfering inhibited viral production and gene expression of HBV, and direct association of HBx with DDB1 promoted viral activities, indicating that DDB1 function is required for viral production. On the other hand, HBx interfered with DDB1-dependent polyubiquitination of PRMT1, arginine methyltransferase 1, suggesting that HBx can also block the function of a subset of CUL4-DDB1 E3 ligases. Thus, we conclude that HBx regulates the function of DDB1 in both positive and negative manners in the context of distinct CUL4-DDB1 complexes and plays different roles in HBV replication cycle.

Differential regulation of mitogen-activated protein kinase signaling pathways in human with different types of mitral valvular disease.

BACKGROUND: Mitogen-activated protein kinases (MAPKs) are considered to play a prominent role in cardiac development, function, and pathogenesis. The different types of mitral valvular disease (MVD), including mitral regurgitation (MR) and mitral stenosis (MS), have different underlying pathophysiologic changes, but the precise intracellular signal transduction mechanisms are not clear. Thus, we investigated the differential regulation of MAPK signaling pathways in humans with different types of MVD. METHODS: Left atrial appendage tissue samples from 32 patients with MVD who were undergoing mitral valve replacement surgery were studied. Serum angiotensin II concentrations were measured using enzyme-linked immunosorbent assay. The expression of MAPK pathway-related genes and proteins was assessed using quantitative polymerase chain reaction, Western blot, and immunohistochemistry. RESULTS: Echocardiography showed that patients with MS had a greater left atrial pressure overload than those with MR. The relative amounts of angiotensin II, extracellular signal-regulated kinase 1, p38α, c-Jun N-terminal kinase 2, c-Fos, activating transcription factor 2, and c-Jun mRNA were significantly upregulated in those with MS compared with those with MR (P < 0.05). The serum angiotensin II concentrations were significantly increased in those with MS compared with those with MR (P = 0.017). Substantial changes in the phosphorylated forms of the MAPK proteins were detected. Phosphorylated extracellular signal-regulated kinase 1/2, and phosphorylated p38 were significantly increased in those with MS compared with those with MR (P < 0.001), and phosphorylated c-Jun N-terminal kinase in the MR group was significantly greater than that in the MS group (P < 0.001). Histologically, more serious myocardial cells losses, myolysis, and interstitial fibrosis were detected in the MS group. CONCLUSIONS: The different types of MVD have different hemodynamic characteristics, and different MAPK pathways were activated in the MR and MS groups, which could lead to diverse left atrial histologic changes.

Celebrating Diversity With Subtask Specialization in Shared Multiagent Reinforcement Learning.

Subtask decomposition offers a promising approach for achieving and comprehending complex cooperative behaviors in multiagent systems. Nonetheless, existing methods often depend on intricate high-level strategies, which can hinder interpretability and learning efficiency. To tackle these challenges, we propose a novel approach that specializes subtasks for subgroups by employing diverse observation representation encoders within information bottlenecks. Moreover, to enhance the efficiency of subtask specialization while promoting sophisticated cooperation, we introduce diversity in both optimization and neural network architectures. These advancements enable our method to achieve state-of-the-art performance and offer interpretable subtask factorization across various scenarios in Google Research Football (GRF).

A role for lymphotoxin in primary Sjogren's disease.

The etiology of salivary gland injury in primary Sjögren's disease is not well understood. We have previously described a mouse model of Sjögren's disease, IL-14α transgenic (IL14αTG) mice, which reproduces many of the features of the human disease. We now demonstrate a critical role for lymphotoxin α (LTA) in the pathogenesis of Sjögren's disease in IL14αTG mice. IL14αTG mice express LTA mRNA in their salivary glands and spleen and produce soluble LTA protein in their salivary secretions. When IL14αTG mice were crossed with LTA(-/-) mice, the IL14αTG.LTA(-/-) mice retained normal salivary gland secretions and did not develop either lymphocytic infiltration of their salivary glands or secondary lymphomas. However, both IL14αTG and IL14αTG.LTA(-/-) mice produced similar amounts of IFN-α and had similar deposition of autoantibodies in their salivary glands. Both IL14α and IL14α/LTA(-/-) mice had similar B cell responses to T-dependent and T-independent Ags, L-selectin expression, and expression of RelA, RelB, and NF-κB2 in their spleens. These studies suggest that LTA plays a critical role in the local rather than systemic inflammatory process of Sjögren's disease. Furthermore, local production of soluble LTA in the salivary glands of IL14αTG mice is necessary for the development of overt Sjögren's disease. Autoantibody deposition alone is not sufficient to produce salivary gland dysfunction. We also demonstrate that LTA is increased in the salivary gland secretions and sera of patients with Sjögren's disease, further strengthening the biological relevance of the IL14αTG model to understanding the pathogenesis of human disease.

PEGylation is effective in reducing immunogenicity, immunotoxicity, and hepatotoxicity of α-momorcharin in vivo.

BACKGROUND AND AIM: α-momorcharin (α-MMC), a type I ribosome-inactivating protein (RIP) from Momordica charantia, is well known for its antitumor and antivirus activities. However, the immunotoxicity and hepatotoxicity hampers its potential therapeutic usage. In order to reduce its toxicity, we had modified the α-MMC with polyethylene glycol (PEG), and detected the toxicity of the PEGylated α-MMC conjugates (α-MMC-PEG) in vivo. MATERIALS AND METHODS: After α-MMC purified from bitter melon seeds, α-MMC-PEG was constructed with a branched 20 kDa (mPEG) 2-Lys-NHS, the tests of immunogenicity, immunotoxicity, and general toxicity of α-MMC-PEG were conducted in guinea pig and rat. RESULTS: The titer of specific IgG in rats, immunized by α-MMC-PEG, were approximately one-third of those that by α-MMC, all the guinea pigs treated with α-MMC died of anaphylaxis shock within 5 min, while no animals treated with α-MMC-PEG died in the active systemic anaphylaxis (ASA) test. The passive cutaneous anaphylaxis (PCA) reaction of α-MMC-PEG challenge in rats was significantly smaller than that of the α-MMC. The liver damage was greatly released, such as the change of globulin (GLB), aspartate aminotransferase (AST), total bilirubin (TBIL) cholesterol (CHOL), albumin (ALB), and the degree of hepatocyte necrosis in repeated toxicity study. CONCLUSIONS: PEGylation is effective in reducing the immunogenicity, immunotoxicity, and hepatotoxicity of α-MMC in vivo.

Overexpression of the c-Myb but not its leukemogenic mutant DNA-binding domain increased adipogenic differentiation in mesenchymal stem cells.

The c-Myb protein is a vital transcription factor that regulates the differentiation of hematopoietic cells. Previous works have noticed that c-Myb is involved in an epigenetic control mechanism, in which the c-Myb DNA-binding domain (DBD) binds to the N-terminal histone tail of H3 to facilitate it acetylation and activate endogenous differentiation genes, while the leukemogenic mutant of c-Myb does not have these functions. However, whether c-Myb has corresponding biologic functions on the differentiation of other cells except for hematopoietic cells has not been explored. In our studies, we constructed the c-Myb wild type and its leukemogenic mutant DBD recombinant adenovirus with replication-defective adenoviral vectors carrying the GFP gene. We compared their roles on adipogenic differentiation efficiency in human bone marrow-derived mesenchymal stem cells (hMSCs). Our results demonstrated that the overexpression of c-Myb could enhance adipogenic differentiation in hMSCs, while the overexpression of its leukemogenic mutant blocked the adipogenic differentiation to a certain extent. These suggest that c-Myb play an important role in the hMSCs differentiation too, which is consistent with the epigenetic control mechanism of c-Myb.

[Preparation and identification of monoclonal antibody against hMOF].

OBJECTIVE: To prepare and identify the monoclonal antibody (mAb) against hMOF. METHODS: BALB/C mice were immunized with protein from the spleen cells isolated and fused with SP2/0 cells. After several rounds of screening and cloning, the hybridoma cell strain secreting anti-hMOF mAb was obtained. Its specificity was evaluated with ELISA and Western blot, and the titer, immunoglobulin subtype and affinity of the mAb were measured. RESULTS: One cell strains of hybridoma were obtained and named as 4C1C8. The anti-hMOF mAb secreted by the hybridoma cell strain was identified as IgG1 subtype. The mAb titers in ascitic fluid were 1 409600, as determined with ELISA with an affinity reaching to 7.65 x 10(6) L/mol. Western blot demonstrated that the antibodies could specifically recognize the immunogen. The cell immunohistochemistry proved that the antibody could recognize the hMOF antigens expressed on the normal cells HL7702. CONCLUSION: The success in anti-hMOF mAb preparation provides the basis for further study of hMOF.

[Association study on single nucleotide polymorphisms in HTRA1 gene and rheumatoid arthritis].

OBJECTIVE: To study the association between the single nucleotide polymorphisms (SNPs) in the high-temperature requirement A-1 (HTRA1) gene and rheumatoid arthritis (RA) in Chinese Han population. METHODS: Five SNPs in the HTRA1 gene (rs2014307, rs2248799, rs2300433, rs714816 and rs2268356) were genotyped by ABI Snapshot method in Han Chinese cohort composed of 344 patients with RA and 288 healthy controls. The serum rheumatoid factor (RF) and C-reactive protein (CRP) of the patients were determined by endpoint nephelometry method. RESULTS: Genotypes of all the five SNPs in the HTRA1 gene were not significantly different between the RA patients and controls (P> 0.05). Haplotypes generated by these five SNPs did not show significantly difference between the two groups either (P> 0.05). Serum RF levels in the RA patients had no significant difference among the genotypes for four SNPs (rs2014307, rs2248799, rs714816, and rs2268356) in the HTRA1 gene, while RF levels in the RA patients with genotypes AA+AG of the rs2300433 locus were significantly higher than that in genotype GG carriers (P< 0.05). Serum CRP levels in the RA patients had no significant difference among the genotypes for all the five SNPs. CONCLUSION: Author's results suggested that although the five SNPs in the HTRA1 gene were not associated with RA in Chinese Han population, RF levels in the RA patients with genotypes AA and AG in the rs2300433 locus were significantly higher than the GG carriers. The HTRA1 role in RF regulation needs to be further investigated.

[Preparation and identification of a monoclonal antibody against recombinant human L-type pyruvate kinase N].

OBJECTIVE: To prepare and identify the monoclonal antibody (mAb) against pyruvate kinase N terminal (PK-N). METHODS: BALB/C mice were immunized with immunogen PK-N-GST-tag. Then the spleen cells were isolated and fused with SP2/0 cells. After several rounds of detecting and cloning, the hybridoma cell strains secreting anti-PK-N mAb were obtained. Its specificity was evaluated with ELISA and Western blot, and the titer, immunoglobulin subtype and affinity of the mAb were measured. RESULTS: Two cell strains of hybridoma, 2B2E4G and 2C6F5, were obtained. The hybridoma cell strains secreting anti-PK-N mAb belonged to IgG2b subtype, with a mAb titer in ascetic fluid of 1 : 409600 and 1 : 102400, respectively. Their affinity reached 3.54 x 10(8) L/mol and 2.72 x 10(8) L/mol, respectively, as determined by ELISA. Western blot demonstrated that the mAb could specifically recognize the immunogen and the natural cell lysis protein. The cell immunohistochemistry proved that the antibody could recognize human L type pyruvate kinase expressed in the plasma of HL-7702 cell strain and paraffin slice of hepatoma. CONCLUSION: The success in anti-PK-N mAb preparation provides a foundation for further studies into glycolysis in normal condition and metabolic diseases.

Brain Functional Alterations in Long-term Unilateral Hearing Impairment.

BACKGROUND: The rate of patients with unilateral hearing impairments (UHI) increase with age and are characterized by asymmetric auditory afferents in which auditory information is asymmetrically transmitted to the brain. Long-term bilateral hearing imbalance can cause abnormal functional changes in the cerebral cortex. However, the relationship between functional alterations in the brain and the severity of the hearing impairment remains unclear. METHODS: This study included 33 patients with UHI (left-sided impairment in 17 and right-sided impairment in 16) and 32 healthy patients. All participants underwent resting-state, blood oxygen level dependent functional magnetic resonance imaging. Fractional amplitude of low frequency fluctuation (fALFF) values were calculated after data preprocessing and compared among the left-sided and right-sided impairment groups and the control group. Pure tone audiometry was used to evaluate patients' hearing impairment level. The correlation between fALFF values of abnormal brain regions and the duration and severity of hearing impairment was analyzed. RESULTS: Results provide evidence for altered resting-state functional activities in the brain of patients with left or right long-term UHI, with significantly increased fALFF values in the Heschl's gyrus, superior temporal gyrus, and insula were observed. Moreover, complicated networks reorganization involved in the visual, cognitive, sensorimotor and information transmission functions except for the auditory function and some brain regions exhibited functional changes only in the one-sided impairment group. In addition, the severity of hearing impairment is related with the functional activities in the bilateral Heschl's gyrus, bilateral insula, right superior temporal gyrus, and left middle frontal gyrus. CONCLUSION: In conclusion, alterations in functional activity are observed in the brains of patients with long-term hearing impairments and multiple brain regions within different functional networks are involved in the brain functional remodeling. The brain reintegration mechanism appears to be asymmetrical and the lateralization pattern in the contralateral brain hemisphere for auditory information processing related with the severity of hearing impairment.

IL-14 alpha, the nexus for primary Sjögren's disease in mice and humans.

To evaluate the role of interleukin 14 alpha (IL-14a) in Sjögren's syndrome (SS), we evaluated the expression of IL-14a in the peripheral blood lymphocytes (PBL) of patients with primary and secondary SS and normal controls by quantitative RT-PCR. In addition, transgenic IL-14a mice were analyzed from 6 weeks of age to death for both histological and immunological features of Sjögren's disease. Patients with both primary and secondary Sjögren's syndrome expressed IL-14a at statistically higher levels in their peripheral blood compared to normal controls matched for age, sex and ethnic group. Transgenic mice in which IL-14a expression was increased constitutively were previously demonstrated to develop hypergammaglobulinemia, autoantibodies, infiltration of the parotid glands with lymphocytes, mild immune-complex mediated renal disease and large B cell lymphoma. In this paper we expand these observations to demonstrate that these mice develop all the clinical and immunological features of primary Sjögren's disease in the same relative time frame as patients with primary Sjögren's disease: stage 1-early hypergammaglobulinemia and autoantibody production, stage 2-decreased salivary gland function with early lymphocytic infiltration of the submandibular glands only, but antibody deposition in the submandibular and parotid glands, stage 3-lymphocytic infiltration of the submandibular, parotid and lacrimal glands with B and T lymphocytes and plasma cells along with interstitial lung disease and mild renal disease, and stage 4-large B cell lymphoma. Thus IL-14a is important in the pathophysiology of Sjögren's disease. The IL-14a transgenic mouse is a novel animal model that can be utilized to understand the pathophysiology of Sjögren's disease.

Dermatopontin is expressed in human liver and is downregulated in hepatocellular carcinoma.

Dermatopontin (DPT) was recently found as a downstream target of vitamin D receptor, which is a key molecule in the 1,25-dihydroxy-vitamin D(3) anti-hepatoma proliferation pathway. MCTx-1 from Millepora, a homolog of DPT, is identified as a cytotoxin towards leukemia cells. The aim of this study was to analyze DPT expression in hepatocellular carcinoma (HCC) based on the analysis for DPT gene in normal tissues in order to estimate its function in the progression of HCC. DPT mRNA expression was analyzed in normal tissues and HCC cell lines by RT-PCR, and in HCC tissue by RT-PCR and real-time PCR. Its protein was examined in HCC tissues by Western blot and immunohistochemistry assays. Meanwhile, transforming growth factor-beta1 (TGF-beta1) that is closely associated with HCC and DPT was observed by immunohistochemistry in HCC tissues. The results showed that DPT mRNA was strongly expressed in human fetal and adult liver, kidney, and spleen, weakly in ovary and heart, and absent in other tissues and HCC cell lines examined. Its mRNA was significantly downregulated in HCC tissues, while its protein was weakly expressed in tumor compared with non-tumor. DPT is located mainly in the cytoplasm of several cell types in the liver; it has been identified also in the extracellular matrix of the skin. TGF-beta1 was observed in extensive tumor tissue of HCC. This fact suggests that DPT can play various roles in different tissues and might be a molecule related to carcinogenesis and the progression of HCC via possible interaction with TGF-beta1 and other potential mechanisms.

[Linkage analysis of one family with autosomal dominant high myopia].

OBJECTIVE: To map the high myopia gene in a Chinese family with autosomal dominant high myopia. METHODS: A family with autosomal dominant high myopia in three generations was collected. Eighteen short-tandem-repeat markers on previously reported loci linked to high myopia were chosen for genotyping and two-point linkage analysis was carried out. RESULTS: The spherical equivalent of affected individuals ranges from -6.00D to -20.00D and the genetic pattern is autosomal dominant. The LOD score was less than -1 in all 18 microsatellite markers, indicating that there was no linkage between these markers and the high myopia related genes in this family. CONCLUSION: A novel myopia locus for high-grade myopia may exist in the kindred. Genome-wide scan will be needed to determine this novel locus.

[Inhibition of proliferation in MCF-7 breast cancer cells by plasmid-based siRNA targeting to oncogene c-myc].

OBJECTIVE: To investigate the effects of plasmid-based siRNA targeting to oncogene c-myc on c-myc/ c-Myc expressions and cells proliferation in MCF-7 breast cancer cells. METHODS: siRNA eukaryotic expression plasmid p-Mat01-1 targeting to the sequence 589-609 of oncogene c-myc and its mismatch plasmid p-Mis09-1 were constructed, and transiently transfected MCF-7 cells using Lipo2000. Semi-quantitative RT-PCR and Western blot were used to analyze the expressions of c-myc/c-Myc in MCF-7 cells, and cells proliferation was detected by MTT assay. RESULTS: p-Mat01-1 inhibited the expressions of c-myc mRNA (24 h: P < 0.01) and c-Myc protein (5 d. P < 0.01) in MCF-7 cells as compared with pEGFP-C1 and p-Mis09-1 controls, and suppressed the proliferation of MCF-7 cells significantly (3 d: P < 0.05, 5, 7 d: P < 0. 01). CONCLUSION: Plasmid-based siRNA targeting to oncogene c-myc could inhibit the expressions of c-myc/c-Myc in MCF-7 breast cancer cells efficiently, suggesting that the downregulation of c-myc/c-Myc could suppress the proliferation of MCF-7 cells in vitro.

[The preparation and identification on monoclonal antibody to platelet-derived growth factor receptor].

OBJECTIVE: Through genetic engineering to produce the fusion protein of glutathione S-transferase (GST) linked to amino-terminal end of platelet-derived growth factor receptor (PDGFR), and to prepare the bioactive monoclonal antibody. METHODS: With taking GST-PDGFR-N fusion protein as immunogen, the anti-PDGFR monoclonal antibody was produced by using the hybridoma technique, of which then the antigen binding characteristic was identified by indirect enzyme-linked immunosorbent assay (ELISA), Western blot and immunohistochemistry methods. RESULTS: Two cell strains of hybridoma were obtained and named as 3B12F5 and 3C6H7C11 which secreted the anti-PDGFR monoclonal antibody, of which the class and subtype identification demonstrated both strains to produce all type of IgG1. The indirect ELISA result showed that the titers of ascites fluid which two hybridoma induced were 1 : 102400 and 1 : 25600. Western blot demonstrated that the two antibodies could recognize specifically the immunogen on PDGFR and U251 cell line. The cell immunohistochemistry proved that the antibody could recognize the expressed PDGFR antigens of neurogliocytoma U251 and bladder carcinoma BIU87 cell lines. CONCLUSION: We prepare successfully the PDGFR monoclonal antibody and provide a useful tool for researching on the PDGFR expression and clinical detection.

Superparamagnetic iron oxide nanoparticles for MR imaging of pancreatic cancer: Potential for early diagnosis through targeted strategies.

Superparamagnetic iron oxide nanoparticles (SPION)-based magnetic resonance imaging is a powerful, noninvasive tool in biomedical imaging. The recent embedding of SPIO in nanoencapsulations that had different controllable surface properties has now made it possible to use SPIO in the imaging of metabolic processes. The two major issues to realize maximized and selective SPIO cancer targeting are the minimization of macrophage uptake and the preferential binding to cancerous cells over healthy neighbor cells. The utility of SPIO has been shown in clinical applications using a series of marketed SPION-based contrast agents. Applications have ranged from detecting inflammatory diseases to the specific identification of cell surface markers expressed on tumors. This review focuses on iron-oxide-based nanoparticles, to include the physiochemical properties of SPION surface engineering and its synthetic methods as well as SPIO imaging applications and specifically targeted SPIO conjugates (e.g. targeted probes) for labeling cancerous, cell-surface molecules. As a specific application of this technology, we discuss its use in the imaging of pancreatic duct adenocarcinoma in addition to its potential for use in early diagnosis through targeted strategies.

PEGylation alleviates the non-specific toxicities of Alpha-Momorcharin and preserves its antitumor efficacy in vivo.

Alpha-Momorcharin (α-MMC) is a ribosome inactivating protein from Momordica charantia with anti-tumor activity. Previously, we had observed that modification of α-MMC with polyethylene glycol (PEG) could reduce toxicity, but it also reduces its anti-tumor activity in vitro. This study aims to investigate whether the metabolism-extended properties of α-MMC resulting from PEGylation could preserve its anti-tumor efficacy in vivo through pharmacokinetics and antitumor experiments. The pharmacokinetics experiments were conducted in rats using the TCA (Trichloroacetic Acid) method. Antitumor activity in vivo was investigated in murine mammary carcinoma (EMT-6) and human mammary carcinoma (MDA-MB-231) transplanted tumor mouse models. The results showed that PEGylation increased the plasma half-life of α-MMC in rats from 6.2-7.5 h to 52-87 h. When administered at 1 mg/kg, α-MMC-PEG and α-MMC showed similar anti-tumor activities in vivo, with a T/C% of 38.56% for α-MMC versus 35.43% for α-MMC-PEG in the EMT-6 tumor model and 36.30% for α-MMC versus 39.88% for α-MMC-PEG in the MDA-MB-231 tumor model (p > 0.05). Importantly, at the dose of 3 mg/kg, all the animals treated with α-MMC died while the animals treated with α-MMC-PEG exhibited only moderate toxic reactions, and α-MMC-PEG exhibited improved anti-tumor efficacy with a T/C% (relative tumor growth rate) of 25.18% and 21.07% in the EMT-6 and MDA-MB-231 tumor models, respectively. The present study demonstrates that PEGylation extends the half-life of α-MMC and alleviates non-specific toxicity, thereby preserving its antitumor efficacy in vivo, and a higher lever of dosage can be used to achieve better therapeutic efficacy.

A novel water-soluble benzothiazole derivative BD926 triggers ROS-mediated B lymphoma cell apoptosis via mitochondrial and endoplasmic reticulum signaling pathways.

Benzothiazole derivatives are known for various biological activities, and their potency in cancer therapy have received considerable attention in recent years. However, the poor water solubility of most benzothiazole derivatives has limited their clinical application. We developed BD926, a novel water-soluble benzothiazole derivative and showed here that it could inhibit the proliferation and induce apoptosis of human Ramos B-lymphoma cells. We further showed that BD926 triggered apoptosis through both mitochondria and endoplasmic reticulum pathways. Moreover, BD926 caused cell cycle arrest at G0/G1 stage. Furthermore, accumulation of reactive oxygen species (ROS) were observed after BD926 treatment and ROS inhibitor was able to attenuate BD926-induced apoptosis, which suggested that BD926-induced apoptosis may be due to over-producing ROS. These results demonstrate the anticancer effects of BD926 in cell models and raise the possibility for the application of BD926 in cancer therapy.