Emicizumab, A Bispecific Antibody to Factors IX/IXa and X/Xa, Does Not Interfere with Antithrombin or TFPI Activity In Vitro.

Emicizumab is a humanized bispecific antibody that binds simultaneously to factor (F) IXa and FX replacing the cofactor function of FVIIIa. Because emicizumab recognizes FIX/FIXa and FX/FXa, a question may arise whether emicizumab competes with antithrombin (AT) and/or tissue factor pathway inhibitor (TFPI), thereby enhancing overall hemostatic potential by blocking their antihemostatic effects. To address this question, we performed enzymatic assays using purified coagulation factors to confirm whether emicizumab interferes with the action of AT on FIXa or FXa, or with the action of TFPI on FXa.

Treatment with anti-IL-6 receptor antibody prevented increase in serum hepcidin levels and improved anemia in mice inoculated with IL-6-producing lung carcinoma cells.

Background: Hepcidin, a key regulator of iron metabolism, is produced mainly by interleukin-6 (IL-6) during inflammation. A mechanism linking cancer-related anemia and IL-6 through hepcidin production is suggested. To clarify the hypothesis that overproduction of IL-6 elevates hepcidin levels and contributes to the development of cancer-related anemia, we evaluated anti-IL-6 receptor antibody treatment of cancer-related anemia in an IL-6-producing human lung cancer xenograft model.

1α,25(OH)2D3 downregulates gene expression levels of muscle ubiquitin ligases MAFbx and MuRF1 in human myotubes.

Clinical trials involving in patients with osteoporosis have reported that activated vitamin D3 (1α,25(OH)2D3, calcitriol) can prevent falling by acting on the skeletal muscles. However, pharmacological mechanisms of 1α,25(OH)2D3 with respect to skeletal muscle hypertrophy or atrophy are still poorly understood. Therefore, we examined changes in the expression of several related genes in human myotubes to test whether 1α,25(OH)2D3 influences hypertrophy and atrophy of skeletal muscle.

Combining onartuzumab with erlotinib inhibits growth of non-small cell lung cancer with activating EGFR mutations and HGF overexpression.

Erlotinib, a tyrosine kinase inhibitor of the epidermal growth factor receptor (EGFR-TKI), benefits survival of patients with non-small cell lung cancer (NSCLC) who harbor activating EGFR mutations. However, elevated expression of hepatocyte growth factor (HGF), a ligand of the MET receptor tyrosine kinase, causes erlotinib resistance. Because onartuzumab, a monovalent antibody to MET, blocks HGF-induced MET activation, the addition of onartuzumab to erlotinib may improve therapeutic efficacy.

Melting curve analysis for mutations of EGFR and KRAS.

Epidermal growth factor receptor (EGFR) and v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations are common in non-small cell lung cancer (NSCLC) and colorectal cancer (CRC). The aim of the present study was to develop a simple and versatile tool to determine EGFR and KRAS mutations for pre-clinical research in the laboratory. We developed a melting curve analysis to detect exon 19 deletion, L858R mutation, and T790M mutation of EGFR, and codon 12/13 and codon 61 mutations of KRAS using LightCycler480 with mutation-specific sensor and anchor probes.

Importance of formalin fixing conditions for HER2 testing in gastric cancer: immunohistochemical staining and fluorescence in situ hybridization.

Background: Accurate and reliable assessment of human epidermal growth factor receptor type 2 (HER2) status is important for selecting patients with gastric cancer who may benefit from trastuzumab treatment. Here we examined the impact of formalin fixing conditions on HER2 immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) in xenografted tumor tissues.

Methods: Xenografted tumor tissues of the human gastric cancer cell lines NCI-N87, SCH, and SNU-16 were collected and kept at room temperature for 0, 6, or 24 h before being fixed with 10 % neutral buffered formalin (NBF) for 24 h or 5, 7, or 10 days and embedded in paraffin.

Loss of an EGFR-amplified chromosome 7 as a novel mechanism of acquired resistance to EGFR-TKIs in EGFR-mutated NSCLC cells.

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) show notable effects against non-small cell lung cancers (NSCLCs) harboring EGFR-activating mutations. However, almost all patients eventually acquire resistance to EGFR-TKIs. In this study, we established novel erlotinib resistant NSCLC cells and examined their resistant mechanisms.

Enhanced antitumor activity of trastuzumab emtansine (T-DM1) in combination with pertuzumab in a HER2-positive gastric cancer model.

Human epidermal growth factor receptor 2 (HER2)-targeted therapy by trastuzumab has become increasingly important for treating HER2-positive cancers, and trastuzumab emtansine (T-DM1) is expected to serve as an effective alternative to trastuzumab. Pertuzumab, a HER2 dimerization inhibitor, showed prolonged progression-free survival when used with trastuzumab for HER2-positive breast cancer. In this study, we investigated the effect of combining T-DM1 and pertuzumab on xenografted gastric tumors.

Biomarkers for antitumor activity of bevacizumab in gastric cancer models.

Background: Bevacizumab is a humanized monoclonal antibody to human vascular endothelial cell growth factor (VEGF) and has been used for many types of cancers such as colorectal cancer, non-small cell lung cancer, breast cancer, and glioblastoma. Bevacizumab might be effective against gastric cancer, because VEGF has been reported to be involved in the development of gastric cancer as well as other cancers. On the other hand, there are no established biomarkers to predict the bevacizumab efficacy in spite of clinical needs.

Continuous inhibition of epidermal growth factor receptor phosphorylation by erlotinib enhances antitumor activity of chemotherapy in erlotinib-resistant tumor xenografts.

Erlotinib, an epidermal growth factor receptor tyrosine kinase inhibitor, has been shown to have benefits for non-small cell lung cancer and pancreatic cancer patients; however, almost all patients develop progressive disease during the therapy. On the other hand, it has been reported that a tumor continues to express epidermal growth factor receptor even after developing progressive disease. To demonstrate the clinical relevance of erlotinib treatment after progressive disease, we investigated whether continuous administration of erlotinib in combination with chemotherapy has a useful effect on progressive disease development during erlotinib treatment.

Pertuzumab in combination with trastuzumab shows significantly enhanced antitumor activity in HER2-positive human gastric cancer xenograft models.

Purpose: We investigated the antitumor activity of the combination of two different humanized monoclonal human epidermal growth factor receptor (HER) 2 antibodies, pertuzumab and trastuzumab, for gastric cancer.

Experimental Design: Tumor mouse xenograft models were used to examine antitumor activity. Cell proliferation was examined using crystal violet staining.

Effect of erythropoietin on human tumor growth in xenograft models.

Recombinant human erythropoietin (rhEPO) has been used in the EU and the United States for the treatment of anemia in cancer patients after myelosuppressive chemotherapy or radiotherapy. However, several conflicting results have been reported concerning the detrimental effect of rhEPO on survival benefit in cancer patients. In experimental studies, contradictory results were also reported in in vitro tumor cell proliferation studies and in vivo tumor growth studies using tumor cells expressing EPO-receptor (EPO-R).

Preclinical study of prolonged administration of trastuzumab as combination therapy after disease progression during trastuzumab monotherapy.

Purpose: The clinical relevance of prolonged trastuzumab administration in combination therapy beyond progressive disease (PD) has been suggested. Here, we examined whether trastuzumab treatment is effective in combination after failing to show antitumor activity as monotherapy in HER2-positive human breast cancer xenograft models.

Methods: We established trastuzumab PD models with HER2-positive breast cancer xenograft models and compared the antitumor activity of trastuzumab in combination with a taxane versus monotherapy with a taxane in the models subsequent to tumor progression under trastuzumab monotherapy.

Antitumor activity of bevacizumab in combination with capecitabine and oxaliplatin in human colorectal cancer xenograft models.

To understand the mechanisms of the effects of combination treatments, we established animal models showing antitumor activity of bevacizumab as a monotherapy and in combination with capecitabine or capecitabine and oxaliplatin and measured thymidine phosphorylase (TP) and vascular endothelial growth factor (VEGF) levels. Tumor-inoculated nude mice were treated with bevacizumab, capecitabine, and oxaliplatin, alone or in combination, after tumor growth was confirmed and volume and microvessel density (MVD) in tumors were evaluated. Levels of TP and VEGF in the tumor were examined by ELISA.

Novel models of cancer-related anemia in mice inoculated with IL-6-producing tumor cells.

We established models of cancer-related anemia in mice from subcutaneous inoculation of two IL-6-producing cancer cell lines, human lung cancer cell line LC-06-JCK and murine colon26 clone 5 colon cancer cells. In both models, elevated levels of IL-6 were detected in sera and hemoglobin levels significantly decreased compared with non-tumor-bearing mice. In the LC-06-JCK model, serum albumin levels also decreased with elevated levels of human IL-6 in sera.

Involvement of cyclooxygenase-2 in the tumor site-dependent production of parathyroid hormone-related protein in colon 26 carcinoma.

It has been shown that in the mouse colon 26 tumor model, tumors grown in the subcutis (subcutis colon 26) caused early onset of cachectic syndromes, whereas those in the liver (liver colon 26) did not. Both interleukin (IL)-6 and parathyroid hormone-related protein (PTHrP) were involved in the development of cachectic syndromes in this tumor model. However, whether expression of PTHrP and IL-6 is differently regulated in the tumor microenvironment is unclear.

Antitumor activity of trastuzumab in combination with chemotherapy in human gastric cancer xenograft models.

Purpose: To clarify the antitumor activity of trastuzumab and its potential as an effective treatment for gastric cancer patients.

Methods: Levels of HER2 expression in tumor tissues of gastric cancer cell lines were examined using immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and mRNA quantification. Efficacy of trastuzumab was examined as a single agent or in combination with chemotherapeutic agents widely used clinically for gastric cancers in HER2-overexpressing human gastric cancer xenograft models.

Capecitabine improves cancer cachexia and normalizes IL-6 and PTHrP levels in mouse cancer cachexia models.

Purpose: To clarify the potential of parathyroid hormone-related protein (PTHrP) and interleukin-6 (IL-6) as cachectic factors in a colon 26 model and the effects of capecitabine on cancer cachexia as determined by plasma levels of IL-6 and PTHrP and body weight loss.

Methods: From two colon 26 sublines-cancer cachectic clone20 and non-cachectic clone5 plasma levels of PTHrP protein and mRNA expression levels in tumor tissues were compared. An IL-6 neutralizing antibody, a PTHrP neutralizing antibody, and capecitabine were administered into mice bearing clone20 and their anticachectic effects evaluated.

Preferential inhibition of bone metastases by 5'-deoxy-5-fluorouridine and capecitabine in the 4T1/luc mouse breast cancer model.

5'-deoxy-5-fluorouridine (5'-DFUR) and capecitabine are oral anti-cancer agents, which are enzymatically converted to 5-fluorouracil (5-FU) by thymidine phosphorylase in humans and uridine phosphorylase in mice. Since the activity of these phosphorylases is higher in cancerous tissue than in normal tissue, systemic administration of 5'-DFUR and capecitabine achieves high intratumoral 5-FU levels and low adverse effects on non-tumoral tissue. Accordingly, 5'-DFUR and capecitabine are widely used for the treatment of cancer patients.

Sequential treatment with irinotecan and doxifluridine: optimal dosing schedule in murine models and in a phase I study for metastatic colorectal cancer.

Background: Irinotecan (CPT-11) and doxifluridine (5'-DFUR) are active agents against colorectal cancer. Each drug, however, has the possibility of causing diarrhea.

Methods And Results: First, we determined the optimal dosing regimen in murine models.

Antitumor activity of combinations of anti-HER-2 antibody trastuzumab and oral fluoropyrimidines capecitabine/5'-dFUrd in human breast cancer models.

The anti-HER-2 antibody, trastuzumab (Herceptin), and the oral fluoropyrimidine, capecitabine (Xeloda), are both effective in breast cancer with different modes of action and toxicity profiles. Therefore, the efficacy in combination therapy of these agents for the treatment of HER-2-overexpressing breast cancer was of interest. An antagonistic interaction in vitro between trastuzumab and 5-fluorouracil (5-FUra) in combination has previously been reported.

Schedule dependency of antitumor activity in combination therapy with capecitabine/5'-deoxy-5-fluorouridine and docetaxel in breast cancer models.

Docetaxel and capecitabine are being prescribed for the treatment of breast cancer. In this study, we tried to identify the optimal administration schedule in combination therapy with these anticancer drugs in human cancer xenograft models. Capecitabine was given p.

Tumour inoculation site-dependent induction of cachexia in mice bearing colon 26 carcinoma.

Murine colon 26 carcinoma growing at either subcutaneous (s.c.) or intramuscular (i.