A Tick Cysteine Protease Inhibitor RHcyst-1 Exhibits Antitumor Potential

Background/Aims: We previously identified a potent and tight-binding inhibitor of cysteine proteases from Rhipicephalus haemaphysaloides, RHcyst-1, which belongs to the cystatin type 1 family. Cathepsins, which are members of the cysteine protease family, participate in various pathological processes, including the initiation and development of cancers. The present study aimed to investigate the antitumor effects of RHcyst-1 and to explore the underlying mechanism of these effects. Methods: Different tumor cells were treated with RHcyst-1 in vitro. Proliferation activity was evaluated using Cell Counting Kit-8, and migration and invasion were determined by wound healing and Transwell® invasion assays. In addition, a mouse tumor therapy model was established by inoculating the left forelimb of mice with B16-F10 cells, and tumor progression was evaluated by assessing tumor volume and survival. Flow cytometry was conducted to evaluate myeloid-derived suppressor cells (MDSCs), CD4+, and CD8+ T cell levels in PBMCs and spleens. Immunohistochemistry was performed to analyze immune cell infiltration and angiogenesis in the tumors. Results: RHcyst-1 significantly inhibited the proliferation, migration, and invasion of all four different tumor cells in vitro. Additionally, it inhibited tumor growth and improved survival in vivo. A decrease and an increase in MDSCs levels were observed in PBMCs and in the spleen, respectively, after RHcyst-1 application. Conclusions: Tick RHcyst-1 has potential antitumor efficacy, and the observed antitumor activities may be partly attributable to changes in cathepsin expression and MDSCs levels in the PBMCs and spleens. The findings of the present study suggest that RHcyst-1 may have the potential to be utilized in cancer treatment.

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INCREASED LEVEL OF MIR-204-5P EXPRESSION IN MELANOMA CELLS UNDER THE INFLUENCE OF DACARBAZINE

Siberian Journal of Oncology ◽

10.21294/1814-4861-2019-18-3-45-53 ◽

2019 ◽

Vol 18 (3) ◽

pp. 45-53

Author(s):

S. N. Lavrentiev ◽

M. B. Aksenenko ◽

A. S. Averchuk ◽

A. V. Komina ◽

N. V. Palkina ◽

...

Keyword(s):

Tumor Cells ◽

Animal Behavior ◽

Growth Dynamics ◽

Inhibitory Effect ◽

Melanoma Cells ◽

Migration And Invasion ◽

Antitumor Effects ◽

Metastasis Development

Various types of tissues was analyzed, and the algorithm for summing neutron and photon doses in neutronMiRNA s are involved in the regulation of numerous critical biological processes, including cell proliferation, differentiation, migration and invasion. They function as oncogenes or tumor suppressors according to the nature of the target. It has been previously determined that miR-204-5p miRNA is characterized by the increased level in melanoma. The aim of this study was to determine the effects of changes in the level of microRNA expression when dacarbazine was exposed to melanoma cells in vitro and synthetic miR-204-5p in vivo. The expression levels of miR-204-5p and miR-211 in melanoma cells were determined by real-time PCR. Antitumor effects in vivo were verified in assessing the growth dynamics of the tumor node. Toxic effects were assessed by animal behavior, fluid intake, feed, and ALT , AST , creatinine, urea levels. In the model of melanoma C57BL6, it was revealed that the introduction of the synthetic miR-204-5p did not cause significant changes in the investigated microRNA in tumor cells. At the same time, the antitumor effects of dacarbazine in melanoma cells in vitro led to an increase in the level of the investigated microRNA by more than 20 times. The results of the study indicated the possibility of compensating the level of miR-204-5p under the influence of cytostatic therapy. Taking into account the previously revealed miR-204-5p inhibitory effect on the proliferation of melanoma cells, we can assume that this miRNA can play a role in maintaining the dermal state of tumor cells. Further studies are required to understand the metastasis development and predict the response to antitumor therapy for melanoma.

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Trypanosomatid cysteine protease activity may be enhanced by a kininogen-like moiety from host serum

Biochemical Journal ◽

10.1042/bj3050549 ◽

1995 ◽

Vol 305 (2) ◽

pp. 549-556 ◽

Cited By ~ 15

Author(s):

J D Lonsdale-Eccles ◽

G W N Mpimbaza ◽

Z R M Nkhungulu ◽

J Olobo ◽

L Smith ◽

...

Keyword(s):

Molecular Mass ◽

Protease Inhibitors ◽

Cysteine Protease ◽

Leishmania Donovani ◽

Leishmania Major ◽

Cysteine Proteases ◽

Cysteine Protease Inhibitor ◽

Cysteine Protease Inhibitors ◽

African Trypanosomes

African trypanosomes contain cysteine proteases (trypanopains) the activity of which can be measured by in vitro digestion of fibrinogen, after electrophoresis in fibrinogen-containing SDS/polyacrylamide gels. When assessed by this procedure, trypanopain from Trypanosoma brucei (trypanopain-Tb) is estimated to have a molecular mass of 28 kDa. However, two additional bands of trypanopain activity (87 kDa and 105 kDa) are observed if serum is added to the trypanopain before electrophoresis. Formation of the 87 and 105 kDa bands is frequently accompanied by a reduction in the intensity of the 28 kDa activity which suggests that the extra bands are complexes of the 28 kDa trypanopain-Tb and a molecule from rat serum called rat trypanopain moledulator (rTM). The rTM-induced activation of cysteine proteases is not restricted to T. brucei as it is also observed with proteases from other protozoan parasites such as bloodstream forms of Trypanosoma congolense and the mammalian-infective in vitro-derived promastigote forms of Leishmania donovani and Leishmania major. The physical properties of rTM resemble those of the kininogen family of cysteine protease inhibitors. rTM is an acidic (pI 4.7) heat-stable 68 kDa glycoprotein with 15 kDa protease-susceptible domains. This resemblance between rTM and kininogens was confirmed by the positive, albeit weak, immunoreactivity between anti-(human low-molecular-mass kininogen) antibody and rTM as well as anti-rTM antibody and human low-molecular-mass kininogen. Furthermore, commercial preparations of human-low-molecular-mass kininogen and chicken egg white cystatin mimicked rTM by forming extra bands of proteolytic activity in the presence of trypanopain-Tb. In some instances, low-molecular-mass kininogen was also observed to increase the rate of hydrolysis of 7-(benzyloxycarbonyl-phenylalanyl-arginyl-amido)-4- methylcoumarin by live T. brucei. Although this effect was rather erratic, in no instance was significant inhibition observed when this putative cysteine protease inhibitor was used under these conditions. The activation of parasite cysteine proteases by commonly accepted cysteine protease inhibitors is unexpected and may have important pathological repercussions.

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Construction and Preclinical Evaluation of 211At Labeled Anti-mesothelin Antibodies as Potential Targeted Alpha Therapy Drugs

Journal of Radiation Research ◽

10.1093/jrr/rraa049 ◽

2020 ◽

Vol 61 (5) ◽

pp. 684-690

Author(s):

Xudong Wang ◽

Wenzong Ma ◽

Weihao Liu ◽

Huan Ma ◽

Yuanyou Yang ◽

...

Keyword(s):

Tumor Cells ◽

Tumor Therapy ◽

Molecular Signature ◽

Cell Counting ◽

Targeted Alpha Therapy ◽

Preclinical Evaluation ◽

Antibody Conjugates ◽

Alpha Therapy ◽

Mesothelin Expression

ABSTRACT Targeted alpha therapy (TAT) is a promising tumor therapy that can specifically transport α particle to the vicinity of tumor cells while the normal cells are only slightly irradiated. Mesothelin is a highly promising molecular signature for many types of solid tumors including malignant mesothelioma, pancreatic cancer, ovarian cancer and lung adenocarcinoma etc., while the expression in normal human tissues are limited, thus making mesothelin a promising antigen for TAT. Previously we developed a theoretical model that could predict and optimize in vitro screening of potential TAT drugs. The aim of the study is construction and preclinical evaluation of 211At labeled anti-mesothelin antibodies as potential TAT drugs. Mesothelin expression of two tumor cell lines were confirmed by flow cytometry, and their radiosensitivities were also evaluated. We used two kinds of anti-mesothelin antibodies, ET210–6 and ET210–28, to construct TAT drugs. Then, radiochemical purity, stability in vitro, affinity of the conjugates and mesothelin expression level were assessed. The specific killing of mesothelin-positive cancer cells treated by 211At-ET210–28 and 211At-ET210–6 were studied via Cell Counting Kit-8 assay and colony formation assay. 211At-ET210–28 and 211At-ET210–6 revealed excellent affinity and stability in both phosphate buffer saline and fetal bovine serum environment. Radiolabeled antibody conjugates bound specifically to mesothelin-positive cells in vitro. Both 211At-ET210–28 and 211At-ET210–6 could specifically kill mesothelin-positive cells with negligible damages to mesothelin-negative cells. Our findings provide initial proof-of-concept for the potential use of 211At labeled ET210–28/ET210–6 anti-mesothelin antibody in specific killings of mesothelin-positive tumor cells.

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Nippocystatin, a Cysteine Protease Inhibitor fromNippostrongylus brasiliensis, Inhibits Antigen Processing and Modulates Antigen-Specific Immune Response

Infection and Immunity ◽

10.1128/iai.69.12.7380-7386.2001 ◽

2001 ◽

Vol 69 (12) ◽

pp. 7380-7386 ◽

Cited By ~ 78

Author(s):

Teruki Dainichi ◽

Yoichi Maekawa ◽

Kazunari Ishii ◽

Tianqian Zhang ◽

Baher Fawzy Nashed ◽

...

Keyword(s):

Immune System ◽

Protease Inhibitor ◽

Cysteine Protease ◽

Antigen Processing ◽

Cysteine Proteases ◽

Cysteine Protease Inhibitor ◽

Host Immune System ◽

Nippostrongylus Brasiliensis

ABSTRACT During infection, parasites evade the host immune system by modulating or exploiting the immune system; e.g., they suppress expression of major histocompatibility complex class II molecules or secrete cytokine-like molecules. However, it is not clear whether helminths disturb the immune responses of their hosts by controlling the antigen-processing pathways of the hosts. In this study, we identified a new cysteine protease inhibitor, nippocystatin, derived from excretory-secretory (ES) products of an intestinal nematode,Nippostrongylus brasiliensis. Nippocystatin, which belongs to cystatin family 2, consists of 144 amino acids and is secreted as a 14-kDa mature form. In vivo treatment of ovalbumin (OVA)-immunized mice with recombinant nippocystatin (rNbCys) profoundly suppressed OVA-specific proliferation of splenocytes but not non-antigen-specific proliferation of splenocytes. OVA-specific cytokine production was also greatly suppressed in rNbCys-treated mice. Although the serum levels of both OVA-specific immunoglobulin G1 (IgG1) and IgG2a were not affected by rNbCys treatment, OVA-specific IgE was preferentially downregulated in rNbCys-treated mice. In vitro rNbCys inhibited processing of OVA by lysosomal cysteine proteases from the spleens of mice. Mice with anti-nippocystatin antibodies became partially resistant to infection with N. brasiliensis. Based on these findings, N. brasiliensis appears to skillfully evade host immune systems by secreting nippocystatin, which modulates antigen processing in antigen-presenting cells of hosts.

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A Novel Cysteine Protease Inhibitor of Naegleria fowleri That Is Specifically Expressed during Encystation and at Mature Cysts

Pathogens ◽

10.3390/pathogens10040388 ◽

2021 ◽

Vol 10 (4) ◽

pp. 388

Author(s):

Hương Giang Lê ◽

A-Jeong Ham ◽

Jung-Mi Kang ◽

Tuấn Cường Võ ◽

Haung Naw ◽

...

Keyword(s):

Protease Inhibitor ◽

Cysteine Protease ◽

Expression Profiles ◽

Critical Role ◽

Cyst Formation ◽

Cysteine Proteases ◽

Cysteine Protease Inhibitor ◽

Naegleria Fowleri ◽

Nægleria Fowleri ◽

Cystatin Family

Naegleria fowleri is a free-living amoeba that is ubiquitous in diverse natural environments. It causes a fatal brain infection in humans known as primary amoebic meningoencephalitis. Despite the medical importance of the parasitic disease, there is a great lack of knowledge about the biology and pathogenicity of N. fowleri. In this study, we identified and characterized a novel cysteine protease inhibitor of N. fowleri (NfCPI). NfCPI is a typical cysteine protease inhibitor belonging to the cystatin family with a Gln-Val-Val-Ala-Gly (QVVAG) motif, a characteristic motif conserved in the cystatin family of proteins. Bacterially expressed recombinant NfCPI has a dimeric structure and exhibits inhibitory activity against several cysteine proteases including cathespin Bs of N. fowleri at a broad range of pH values. Expression profiles of nfcpi revealed that the gene was highly expressed during encystation and cyst of the amoeba. Western blot and immunofluorescence assays also support its high level of expression in cysts. These findings collectively suggest that NfCPI may play a critical role in encystation or cyst formation of N. fowleri by regulating cysteine proteases that may mediate encystation or mature cyst formation of the amoeba. More comprehensive studies to investigate the roles of NfCPI in encystation and its target proteases are necessary to elucidate the regulatory mechanism and the biological significance of NfCPI.

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Diaphanous related formin 3 knockdown suppresses cell proliferation and metastasis of osteosarcoma cells

Discover Oncology ◽

10.1007/s12672-021-00415-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Zehua Zhang ◽

Fei Dai ◽

Fei Luo ◽

Wenjie Wu ◽

Shuai Zhang ◽

...

Keyword(s):

Cell Proliferation ◽

Tumor Therapy ◽

Disease Free Survival ◽

Tumor Stage ◽

Migration And Invasion ◽

Osteosarcoma Cell ◽

Proliferation And Metastasis ◽

New Biomarkers

AbstractOsteosarcoma is a malignant osteoblastic tumor that can gravely endanger the lives and health of children and adolescents. Therefore, there is an urgent need to explore new biomarkers for osteosarcoma and determine new targeted therapies to improve the efficacy of osteosarcoma treatment. Diaphanous related formin 3 (DIAPH3) promotes tumorigenesis in hepatocellular carcinoma and lung adenocarcinoma, suggesting that DIAPH3 may be a target for tumor therapy. To date, there have been no reports on the function of DIAPH3 in osteosarcoma. DIAPH3 protein expression in osteosarcoma tissues and healthy bone tissues adjacent to cancer cells was examined by immunohistochemical staining. DIAPH3 mRNA expression correlates with overall survival and reduced disease-free survival. DIAPH3 protein is upregulated in osteosarcoma tissues, and its expression is significantly associated with tumor size, tumor stage, node metastasis, and distant metastasis. Functional in vitro experiments revealed that DIAPH3 knockdown suppressed cell proliferation and suppressed cell migration and invasion of osteosarcoma cell lines MG-63 and HOS. Functional experiments demonstrated that DIAPH3 knockdown inhibited subcutaneous tumor growth and lung metastasis in vivo. In conclusion, DIAPH3 expression can predict the clinical outcome of osteosarcoma. In addition, DIAPH3 is involved in the proliferation and metastasis of osteosarcoma, and as such, DIAPH3 may be a potential therapeutic target for osteosarcoma.

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Loss of PR55α promotes proliferation and metastasis by activating MAPK/AKT signaling in hepatocellular carcinoma

Cancer Cell International ◽

10.1186/s12935-021-01796-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

JiangSheng Zhao ◽

GuoFeng Chen ◽

Jingqi Li ◽

Shiqi Liu ◽

Quan Jin ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Cycle Progression ◽

Lung Metastases ◽

Cell Counting ◽

Migration And Invasion ◽

Signal Pathways ◽

And Migration ◽

Healthy Liver

Abstract Background PR55α plays important roles in oncogenesis and progression of numerous malignancies. However, its role in hepatocellular carcinoma (HCC) is unclear. This study aims to characterize the functions of PR55α in HCC. Methods PR55α expressions in HCC tissues and paired healthy liver samples were evaluated using Western blot and tissue microarray immunohistochemistry. We knocked down the expression of PR55α in SMMC-7721 and LM3 cell lines via small interfering and lentivirus. In vitro cell counting, colony formation, migration and invasion assays were performed along with in vivo xenograft implantation and lung metastases experiments. The potential mechanisms involving target signal pathways were investigated by RNA-sequencing. Results PR55α expression level was suppressed in HCC tissues in comparison to healthy liver samples. Decreased PR55α levels were correlated with poorer prognosis (P = 0.0059). Knockdown of PR55α significantly promoted cell proliferation and migration, induced repression of the cell cycle progression and apoptosis in vitro while accelerating in vivo HCC growth and metastasis. Mechanistic analysis indicated that PR55α silencing was involved with MAPK/AKT signal pathway activation and resulted in increased phosphorylation of both AKT and ERK1/2. Conclusions This study identifies PR55α to be a candidate novel therapeutic target in the treatment of HCC.

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The cancer glycocalyx mediates intravascular adhesion and extravasation during metastatic dissemination

Communications Biology ◽

10.1038/s42003-021-01774-2 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Giovanni S. Offeddu ◽

Cynthia Hajal ◽

Colleen R. Foley ◽

Zhengpeng Wan ◽

Lina Ibrahim ◽

...

Keyword(s):

Hyaluronic Acid ◽

Tumor Cells ◽

Cancer Progression ◽

Vascular System ◽

Migration And Invasion ◽

Improve Patient Survival ◽

Adhesive Interactions ◽

Vitro Model ◽

Metastatic Sites

AbstractThe glycocalyx on tumor cells has been recently identified as an important driver for cancer progression, possibly providing critical opportunities for treatment. Metastasis, in particular, is often the limiting step in the survival to cancer, yet our understanding of how tumor cells escape the vascular system to initiate metastatic sites remains limited. Using an in vitro model of the human microvasculature, we assess here the importance of the tumor and vascular glycocalyces during tumor cell extravasation. Through selective manipulation of individual components of the glycocalyx, we reveal a mechanism whereby tumor cells prepare an adhesive vascular niche by depositing components of the glycocalyx along the endothelium. Accumulated hyaluronic acid shed by tumor cells subsequently mediates adhesion to the endothelium via the glycoprotein CD44. Trans-endothelial migration and invasion into the stroma occurs through binding of the isoform CD44v to components of the sub-endothelial extra-cellular matrix. Targeting of the hyaluronic acid-CD44 glycocalyx complex results in significant reduction in the extravasation of tumor cells. These studies provide evidence of tumor cells repurposing the glycocalyx to promote adhesive interactions leading to cancer progression. Such glycocalyx-mediated mechanisms may be therapeutically targeted to hinder metastasis and improve patient survival.

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Warburg effect-promoted exosomal circ_0072083 releasing up-regulates NANGO expression through multiple pathways and enhances temozolomide resistance in glioma

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-021-01942-6 ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Chenyu Ding ◽

Xuehan Yi ◽

Xiangrong Chen ◽

Zanyi Wu ◽

Honghai You ◽

...

Keyword(s):

Warburg Effect ◽

Lactate Production ◽

Xenograft Model ◽

Cell Counting ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Circular Rnas ◽

Rna Immunoprecipitation ◽

Resistant Cells

Abstract Background Temozolomide (TMZ) resistance limits its application in glioma. Exosome can carry circular RNAs (circRNAs) to regulate drug resistance via sponging microRNAs (miRNAs). miRNAs can control mRNA expression by regulate the interaction with 3’UTR and methylation. Nanog homeobox (NANOG) is an important biomarker for TMZ resistance. Hitherto, it is unknown about the role of exosomal hsa_circ_0072083 (circ_0072083) in TMZ resistance in glioma, and whether it is associated with NANOG via regulating miRNA sponge and methylation. Methods TMZ-resistant (n = 36) and sensitive (n = 33) patients were recruited. The sensitive cells and constructed resistant cells were cultured and exposed to TMZ. circ_0072083, miR-1252-5p, AlkB homolog H5 (ALKBH5) and NANOG levels were examined via quantitative reverse transcription polymerase chain reaction and western blot. The half maximal inhibitory concentration (IC50) of TMZ, cell proliferation, apoptosis, migration and invasion were analyzed via Cell Counting Kit-8, colony formation, flow cytometry, wound healing and transwell assays. The in vivo function was assessed using xenograft model. The N6-methyladenosine (m6A) level was analyzed via methylated RNA immunoprecipitation (MeRIP). Target relationship was investigated via dual-luciferase reporter assay and RNA immunoprecipitation. Warburg effect was investigated via lactate production, glucose uptake and key enzymes expression. Exosome was isolated and confirmed via transmission electron microscopy and specific protein expression. Results circ_0072083 expression was increased in TMZ-resistant glioma tissues and cells. circ_0072083 knockdown restrained the resistance of resistant cells via decreasing IC50 of TMZ, proliferation, migration, invasion and xenograft tumor growth and increasing apoptosis. circ_0072083 silence reduced NANOG expression via blocking ALKBH5-mediated demethylation. circ_0072083 could regulate NANOG and ALKBH5 via targeting miR-1252-5p to control TMZ resistance. Warburg effect promoted the release of exosomal circ_0072083 in resistant cells. Exosomal circ_0072083 from resistant cells increased the resistance of sensitive cells to TMZ in vitro and xenograft model. Exosomal circ_0072083 level was enhanced in resistant patients, and it had a diagnostic value and indicated a lower overall survival in glioma. Conclusion Exosomal circ_0072083 promoted TMZ resistance via increasing NANOG via regulating miR-1252-5p-mediated degradation and demethylation in glioma.

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MYL6B drives the capabilities of proliferation, invasion, and migration in rectal adenocarcinoma through the EMT process

Open Life Sciences ◽

10.1515/biol-2020-0031 ◽

2020 ◽

Vol 15 (1) ◽

pp. 522-531

Author(s):

Jin-Liang Li ◽

Zai-Qiu Wang ◽

Xiao-Li Sun

Keyword(s):

Western Blot ◽

Cell Apoptosis ◽

Rectal Adenocarcinoma ◽

Drug Application ◽

Biological Significance ◽

Expression Level ◽

Cell Counting ◽

Migration And Invasion ◽

Promoting Effect

AbstractObjectiveThis study was designed to explore the biological significance of myosin light chain 6B (MYL6B) in rectal adenocarcinoma.MethodsProfiles on the Oncomine dataset, GEPIA website, and UALCAN-TCGA database were searched to assess the MYL6B expression level in rectal adenocarcinoma tissues and normal tissues. After MYL6B knockdown using siRNA strategy, cell counting kit-8 (CCK-8) and transwell assays were conducted to measure cell proliferation, migration and invasion, respectively. Flow cytometry analysis was conducted to assess cell apoptosis. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blot were performed to detect the expression level of mRNAs and proteins.ResultsThe data showed that overexpression of MYL6B was observed in rectal adenocarcinoma tissues and correlated with a poor prognosis of patients. Functional in vitro experiments revealed that MYL6B knockdown could inhibit proliferation, migration, and invasion of rectal adenocarcinoma cells, while promote cell apoptosis. Moreover, western blot analysis suggested that increased expression of E-cadherin and decreased expression of N-cadherin and Vimentin were induced by si-MYL6B.ConclusionIn summary, this study elaborated on the promoting effect of MYL6B in rectal adenocarcinoma progression, thus providing novel insight for strategies of clinical diagnosis and drug application in the future clinical study.

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