cancer-research

Ancheta L, Bouajram R, Lappi DA (2018) Screening targeting agents and their cell surface biomarkers for high specificity and rapid internalization via cell death and fluorescence. Neuroscience 2018 Abstracts 128.20 / M17. Society for Neuroscience, San Diego, CA.

Summary: Some of the most recent successes in the treatment of cancers or research into passive immunotherapies for neurodegenerative diseases, employ the use of antibodies. These treatments utilize antibodies that either: 1) interfere with cell surface proteins responsible for tumor cell proliferation, 2) act as immune checkpoint inhibitors, or 3) are re-engineered to allow transport of other molecules across the blood-brain barrier (BBB). There are a growing number of antibody and small molecule therapeutic candidates and this demands a quick and efficient technique to screen for biomarkers that internalize effectively upon binding. The method described provides for the efficient determination of internalization of cell surface biomarkers upon binding of antibodies or peptides. This one-step, robust method uses a targeting agent combined with both a fluorescent reporter and a cytotoxic payload. The construct that makes this method effective was formed by cross-linking a fluorescent reporter, in this case fluorescein (FITC) and streptavidin to the ribosome-inactivating protein, Saporin. The conjugate used in screening potential therapeutics is a mixture of a biotinylated targeting agent mixed in a 1:1 molar ratio with FITC-labeled Streptavidinylated-Saporin. The method provides a definitive assay readout: fluorescence within 1 hour and cell death in 72 hours. This method is designed for rapid screening, in a quick and reproducible manner, for specificity and internalization in various cell types to explore suitability of candidates as therapeutics.

Related Products: Streptavidin-ZAP (Cat. #IT-27), FITC-Streptavidin-ZAP (Cat. #IT-85)

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See Also:

• Tan HL et al. Conservation of oncofetal antigens on human embryonic stem cells enables discovery of monoclonal antibodies against cancer. Sci Rep 8:11608, 2018.
• Yuan X et al. Characterization of the first fully macropinocytosing human antibodies human anti-TEM1 scFv in models of solid tumor imaging and immunotoxin-based therapy. Cancer Immunol Immunother 66:367-378, 2017.
• Forsyth PA et al. p75 neurotrophin receptor cleavage by α- and γ-secretases is required for neurotrophin-mediated proliferation of brain tumor-initiating cells. J Biol Chem 289(12):8067-8085, 2014.
• Thakkar JP et al. Epidemiologic and molecular prognostic review of glioblastoma. Cancer Epidemiol Biomarkers Prev 23(10):1985-1996, 2014.
• Kohls M Evaluate Potential Targeting Molecules. Nature Methods , 2006.

Su Y, Liu Y, Behrens CR, Bidlingmaier S, Lee NK, Aggarwal R, Sherbenou DW, Burlingame AL, Hann BC, Simko JP, Premasekharan G, Paris PL, Shuman MA, Seo Y, Small EJ, Liu B (2018) Targeting CD46 for both adenocarcinoma and neuroendocrine prostate cancer. JCI Insight 3(17):e121497. doi: 10.1172/jci.insight.121497 PMID: 30185663

Objective: To investigate the suitability of a CD46 antibody as a metastatic castration-resistant prostate cancer (mCRPC) anti-tumor agent.

Summary: CD46 is an excellent candidate for antibody-based therapy development, which has potential to be applicable to both adenocarcinoma and neuroendocrine types of mCRPC that are resistant to current treatment.

Usage: Biotinylated UA20 IgG and Streptavidin-ZAP were mixed at a molar ratio of 1:1. The conjugate was used in cytotoxicity assays and shown to specifically kill the mCRPC cells.

Related Products: Streptavidin-ZAP (Cat. #IT-27)

Tan HL, Yong C, Tan BZ, Fong WJ, Padmanabhan J, Chin A, Ding V, Lau A, Zheng L, Bi X, Yang Y, Choo A (2018) Conservation of oncofetal antigens on human embryonic stem cells enables discovery of monoclonal antibodies against cancer. Sci Rep 8:11608. doi: 10.1038/s41598-018-30070-z

Objective: To identify and characterize an antibody raised using human embryonic stem cells with potential as a cancer therapeutic.

Summary: Antibody A19 not only binds to undifferentiated hESCs by flow cytometry, it also reacts with ovarian and breast cancer cell lines with low or no binding to normal cells.

Usage: in vitro – Number of viable cells treated showed a decrease in cell number (Hum-ZAP mixed with A19; Streptavidin-ZAP mixed with biotinylated A19). To determine if there were off-target effects, Hum-ZAP and chA19 were incubated with a non-binding cell line OVCAR10; no apparent cytotoxicity was observed. invivo – 5 x 106 SKOV3 cells were implanted s.c. in NUDE mice and Biotinylated A19-Streptavidin-ZAP (ADC), administered ip. The controls were free Saporin and naked A19. By the end of 10 weeks, mice administered with the ADC saw a 60% reduction in tumor size compared to control groups.

Related Products: Hum-ZAP (Cat. #IT-22), Streptavidin-ZAP (Cat. #IT-27), Saporin (Cat. #PR-01)

Hoffmann RM, Crescioli S, Thurston DE, Karagiannis SN (2018) Development and evaluation of T-Zap: a novel antibody-drug conjugate for the treatment of Her2 positive breast cancer. Cancer Res 78:LB-001. doi: 10.1158/1538-7445.AM2018-LB-001 PMID: 909090

Objective: Develop and Evaluate a novel ADC (T-Zap) for breast cancer.

Summary: Binding to target cells of T-Zap was confirmed. Comparison of T-Zap efficacy in breast cancer cell lines with and without resistance against trastuzumab showed a trend for higher efficacy of cell killing by T-Zap in trastuzumab resistant cells compared to T-DM1. Toxicity assays revealed no impact of T-Zap on cell viability in immune cells.

Usage: T-ZAP was made using Biotinylated monoclonal antibody trastuzumab mixed with Streptavidin-ZAP.

Related Products: Streptavidin-ZAP (Cat. #IT-27)

Wüstemann T, Haberkorn U, Babich J, Mier W (2019) Targeting prostate cancer: Prostate-specific membrane antigen based diagnosis and therapy. Med Res Rev 39(1):40-69. doi: 10.1002/med.21508 PMID: 29771460

Summary: Conjugation to the antibody was achieved by reacting the biotinylated humanized antibody to prostate-specific membrane antigen (PMSA) with Streptavidin-ZAP. Binding potency of the conjugate was comparable to that of the naked antibody and in vivo experiments proved potent for selective tumor growth inhibition in mice bearing LNCaP tumors.

Related Products: Streptavidin-ZAP (Cat. #IT-27)

See Also:

• Kuroda K et al. Saporin toxin-conjugated monoclonal antibody targeting prostate-specific membrane antigen has potent anticancer activity. Prostate 70(12):1286-1294, 2010.

Araldi D, Ferrari LF, Levine JD (2018) Role of GPCR (mu-opioid)-receptor tyrosine kinase (epidermal growth factor) crosstalk in opioid-induced hyperalgesic priming (type II). Pain 159(5):864-875. doi: 10.1097/j.pain.0000000000001155

Objective: To determine the the mechanisms mediating the induction of opioid-induced hyperalgesia and the prolongation of prostaglandinE2-induced hyperalgesia in type II hyperalgesic priming.

Summary: Understanding the mechanisms responsible for the induction of type II hyperalgesic priming, a form of neuroplasticity in the peripheral terminal of the primary afferent nociceptor, may provide useful information for the design of drugs with improved therapeutic profiles to treat neuroplasticity induced by chronic use of opioids.

Usage: SSP-SAP was prepared in saline (5 ng/mL), and 20 mL was injected intrathecally into rats, 14 days before nociceptive tests.

Related Products: SSP-SAP (Cat. #IT-11)

Kusano-Arai O, Iwanari H, Kudo S, Kikuchi C, Yui A, Akiba H, Matsusaka K, Kaneda A, Fukayama M, Tsumoto K, Hamakubo T (2018) Synergistic cytotoxic effect on gastric cancer cells of an immunotoxin cocktail in which antibodies recognize different epitopes on CDH17. Monoclon Antib Immunodiagn Immunother 37:1-11. doi: 10.1089/mab.2017.0043

Objective: To determine if an immunotoxin cocktail targeted to multiple epitopes has synergistic effects on low expression level cells, which would expand the applicable range of immunotoxin therapy for cancer.

Summary: The combination of immunotoxins with different mechanisms of action in an antibody cocktail will increase cytotoxic activities and decrease side effects.

Usage: The authors applied a monoclonal antibody (mAb) cocktail for one target protein with multiple epitopes. They generated anti-CDH17 mAbs recognizing different epitopes on CDH17 (Cadherin-17). CDH17 is expressed in gastric cancer, hepatocellular carcinoma, colorectal cancer, and pancreatic cancer and has limited distribution in normal tissues. For preparation of 3 immunotoxins, Streptavidin-ZAP was mixed with biotinylated mAbs in equimolar concentrations for 30 minutes at room temperature. The study provides data to demonstrate that the cocktail of different epitope-recognizing immunotoxins has synergistic cytotoxic effects on CDH17-expressing cells.

Related Products: Streptavidin-ZAP (Cat. #IT-27)

Yuan X, Yang M, Chen X, Zhang X, Sukhadia S, Musolino N, Bao H, Chen T, Xu C, Wang Q, Santoro S, Ricklin D, Hu J, Lin R, Yang W, Li Z, Qin W, Zhao A, Scholler N, Coukos G (2018) Characterization of the first fully human anti-TEM1 scFv in models of solid tumor imaging and immunotoxin-based therapy. Cancer Immunol Immunother 67:329-339. doi: 10.1007/s00262-017-2101-0 PMID: 29313073

Objective: ScFv78 was conjugated with the ribosome-inactivating protein saporin (Streptavidin-ZAP) to evaluate whether scFv78 may be used as a vehicle for theTEM1-targeted delivery of toxins.

Summary: Site-specific, biotinylated scFv78 was conjugated with streptavidin-labeled saporin (Streptavidin-ZAP; Cat. #IT-27) by incubation at room temperature for 1h at a molar ratio of 4:1 (scFv78:ZAP).

Usage: Mouse endothelial cells (MS1) and MS1 cells transduced to express full-length human TEM1 (MS1-TEM1) were cultured in 96-well plates to 30% confluence and then incubated for 96h in the presence of 10-fold serially diluted Streptavidin-ZAP, scFv78, or scFv78-ZAP starting from 40nM down to 0.04nM. The data indicate that scFv78, the first fully human anti-TEM1 recombinant antibody, recognizes both human and mouse TEM1 and has unique and favorable features that are advantageous for the development of imaging probes or antibody-toxin conjugates for a large spectrum of human TEM1-positive solid tumors.

Related Products: Streptavidin-ZAP (Cat. #IT-27)

Cua S, Tan HL, Fong WJ, Chin A, Lau A, Ding V, Song Z, Yang Y, Choo A (2018) Targeting of embryonic annexin A2 expressed on ovarian and breast cancer by the novel monoclonal antibody 2448. Oncotarget 9:13206-13221. doi: 10.18632/oncotarget.24152

Objective: To develop mAbs to potentially target oncofetal antigens and be repurposed for antibody or antibody drug conjugate (ADC) therapy.

Summary: The novel IgG1, 2448, was shown to target a unique glycosylated surface epitope on ANXA2. As a possible therapeutic candidate for ovarian and breast cancer, 2448 demonstrated anti-tumor activity via two independent mechanisms of action.

Usage: Cells were seeded in 96-well plates at 1000 or 2000 cells/well. Primary antibody, 2448 or ch2448 (10 μg/mL) was pre-mixed with appropriate secondary saporin conjugate, Mab-ZAP or Hum-ZAP.  The most significant decreases in cell viability (20% to 60%) were observed against the epithelial IGROV1 and MCF7 cell lines.  ATS created a Custom ADC by direct conjugation of saporin to ch2448 (ch2448-SAP).  As a control, an isotype chimeric IgG was also conjugated to saporin (IgG-SAP). Compared to using secondary saporin conjugates, ch2448-SAP induced and increase of  20–30% cytotoxicity.)

Related Products: Mab-ZAP (Cat. #IT-04), Hum-ZAP (Cat. #IT-22), Custom Conjugates

Lund K, Olsen CE, Wong JJW, Olsen PA, Solberg NT, Høgset A, Krauss S, Selbo PK (2017) 5-FU resistant EMT-like pancreatic cancer cells are hypersensitive to photochemical internalization of the novel endoglin-targeting immunotoxin CD105-saporin. J Exp Clin Cancer Res 36(1):185.. doi: 10.1186/s13046-017-0662-6

Objective: Investigate resistance mechanisms and photochemical strategies to overcome 5-FU resistance in pancreatic adenocarcinoma.

Summary: Expression of CD105 was investigated using RT-qPCR, western blotting, flow cytometry, and fluorescence microscopy, and co-localization of TPCS2a and Anti-CD105-SAP was assessed using microscopy. MTS assay was used to investigate cytotoxic effects of photochemical internalization of Anti-CD105-SAP. For the first time, we demonstrate the promise of PCI-based targeting of CD105 in site-specific elimination of 5-FU resistant pancreatic cancer cells using Anti-CD105-SAP in vitro. PCI-based targeting of CD105 may represent a potent anti-cancer strategy and should be further evaluated in preclinical models.

Usage: Cells were seeded (3000/well) in 96-well plates and allowed to attach overnight. The cells were incubated with the Anti-CD105-saporin (2.4 nM) or Saporin as a control (6.48 nM; Saporin was added in a molecular ratio of 2.7:1 to the immunotoxin) giving an equal ratio of Saporin to immunotoxin), with or without the photosensitizer TPCS2a (0.35 μg/ml) for 18 h.

Related Products: Anti-CD105-SAP (Cat. #IT-80)