Remediation of cadmium-contaminated soil: GLDA-assisted extraction and sequential FeCl3-CaO-based post-stabilization.

Cadmium (Cd) contamination of farmland soils is a growing concern because of its highly toxic impact on ecosystems and human health. Chelator-assisted washing and chemical immobilization are effective remediation strategies for Cd-contaminated soils. Ethylenediaminetetraacetic acid (EDTA) has traditionally been used for soil washing, but its persistence in the environment and subsequent toxicity have raised significant ecological concerns. Consequently, biodegradable chelators have gained increasing attention as eco-friendly alternatives to the persistent chelator, EDTA. Therefore, this study evaluated the performance and efficacy of three biodegradable chelators: L-glutamate-N,N'-diacetic acid (GLDA), methylglycine-diacetic acid (MGDA), and 3-hydroxy-2,2'-iminodisuccinic acid (HIDS) in comparison to EDTA for remediating a real Cd-contaminated agricultural soil. The influence of treatment parameters, including chelator variants, washing time, chelator concentration, solution pH, and liquid-to-soil ratio (L/S) on Cd extraction was studied and optimized to attain the maximum removal rate. Following chelator-assisted washing, the efficacy of a stabilization preference combining FeCl3 and CaO in reducing the leaching potential of residual Cd in chelator-washed soil residues was also investigated. GLDA demonstrated comparable Cd extraction efficiency to EDTA, and the Cd extraction efficiency was found to be positively correlated with the soil washing parameters. However, under the optimized conditions (chelator concentration: 10 mmol L-1; washing time: 3 h; solution pH: 3; L/S ratio: 10:1), GLDA exhibited a higher Cd extraction rate than EDTA or the other chelators. Furthermore, a post-treatment process incorporating FeCl3 and CaO substantially diminished the water-leachable Cd content in the resultant soil residues. The proposed remediation strategy, which combines chemically assisted washing and stabilization, could be a practical option for extracting bulk Cd from soil and reducing the leaching potential of residual Cd.

The dual pocket binding novel tankyrase inhibitor K-476 enhances the efficacy of immune checkpoint inhibitor by attracting CD8+ T cells to tumors.

The Wnt/ß-catenin pathway, which is associated with disease progression, is activated in many cancers. Tankyrase (TNKS) has received attention as a target molecule for Wnt/ß-catenin pathway inhibition. We identified K-476, a novel TNKS inhibitor, a dual pocket binder that binds to both the nicotinamide and ADP-ribose pockets. In a human colon cancer cell line, K-476 specifically and potently inhibited TNKS and led to stabilization of the Axin protein, resulting in Wnt/ß-catenin pathway suppression. Aberrant Wnt/ß-catenin pathway activation was recently reported as a possible mechanism of ineffectiveness in immune checkpoint inhibitor (ICI) treatment. Because the Wnt/ß-catenin pathway activation causes dendritic cell inactivation and suppresses chemokine production, resulting in a paucity of CD8+ T cells in tumor tissue, which is an important effector of ICIs. Thus, TNKS inhibitors may enhance the efficacy of ICIs. To examine whether K-476 enhances the antitumor effect of anti-PD-L1 antibodies, K-476 was administered orally with an anti-PD-L1 antibody to melanoma-bearing C57BL/6J mice. Although K-476 was ineffective as a monotherapy, it significantly enhanced the antitumor effect in combination with anti-PD-L1 antibody. In mice, intra-tumor infiltration of CD8+ T cells was increased by combination treatment. K-476 upregulated the chemokine expression (e.g., Ccl3 and Ccl4), which attracted CD8+ T cells. This was considered to contribute to the increased CD8+ T cells in the tumor microenvironment. Furthermore, while the potential gastrointestinal toxicity of TNKS inhibitors has been reported, it was not observed at effective doses. Thus, K-476 could be an attractive therapeutic option to enhance the efficacy of ICIs.

An anti-ASCT2 monoclonal antibody suppresses gastric cancer growth by inducing oxidative stress and antibody dependent cellular toxicity in preclinical models.

Glutamine is a major nutrient for cancer cells during rapid proliferation. Alanine-serine-cysteine (ASC) transporter 2 (ASCT2; SLC1A5) mediates glutamine uptake in a variety of cancer cells. We previously reported that KM8094, a novel anti-ASCT2 humanized monoclonal antibody, possesses anti-tumor efficacy in gastric cancer patient-derived xenografts. The aim of this study was to investigate the molecular mechanism underlying the effect of KM8094 and to further substantiate the preclinical feasibility of using KM8094 as a potential therapeutic agent against gastric cancer. First, ASCT2 was found to be highly expressed in cancer tissues derived from gastric cancer patients by an immunohistochemical analysis. Next, we performed in vitro studies using multiple gastric cancer cell lines and observed that several gastric cancer cells expressing ASCT2 showed glutamine-dependent cell growth, which was repressed by KM8094. We found that KM8094 inhibited the glutamine uptake, leading to the reduction of glutathione (GSH) level and the elevation of oxidative stress. KM8094 suppressed the cell cycle progression and increased the apoptosis. Furthermore, KM8094 exerted antibody dependent cellular cytotoxicity (ADCC) against human gastric cancer cells in vitro. Finally, in vivo studies revealed that KM8094 suppressed tumor growth in several gastric cancer xenografts. This effect was enhanced by docetaxel, one of the agents commonly used in gastric cancer therapy. Thus, our findings suggest that KM8094 is a potential new therapeutic agent for gastric cancer expressing ASCT2, which blocks the cellular glutamine metabolism and possesses ADCC activity.

Novel anticarcinoembryonic antigen antibody-drug conjugate has antitumor activity in the existence of soluble antigen.

Carcinoembryonic antigen (CEA) is a classic tumor-specific antigen that is overexpressed in several cancers, including gastric cancer. Although some anti-CEA antibodies have been tested, to the best of our knowledge, there are currently no clinically approved anti-CEA antibody therapies. Because of this, we have created the novel anti-CEA antibody, 15-1-32, which exhibits stronger binding to membrane-bound CEA on cancer cells than existing anti-CEA antibodies. 15-1-32 also shows poor affinity for soluble CEA; thus, the binding activity of 15-1-32 to membrane-bound CEA is not influenced by soluble CEA. In addition, we constructed a 15-1-32-monomethyl auristatin E conjugate (15-1-32-vcMMAE) to improve the therapeutic efficacy of 15-1-32. 15-1-32-vcMMAE showed enhanced antitumor activity against gastric cancer cell lines. Unlike with existing anti-CEA antibody therapies, antitumor activity of 15-1-32-vcMMAE was retained in the presence of high concentrations of soluble CEA.

Five-sixth Nephrectomy in Female Common Marmosets(Callithrix jacchus) as a Chronic Renal Failure Model: -A Longitudinal Course of Serum Biochemical, Hematological and Histopathological Changes-.

To assess the relevance and availability of subtotal nephrectomized common marmoset monkeys as a chronic renal failure (CRF) model, we observed for 26 weeks the pathophysiological condition of female marmosets subjected to five-sixth surgical nephrectomy (5/6Nx) by a two-step surgical method. The 5/6Nx marmosets showed a significant increase in serum levels of urea nitrogen, creatinine and cystatin-C immediately after 5/6Nx surgery. These renal disorder parameters subsequently tended to decrease with the passage of time but remained higher than the control levels by the end of the study. Hyperplastic parathyroid glands, a high turnover state of osteodystrophy in the femoral bone with higher serum ALP activity and anemia with hypocellularity of bone marrow were evident. The 5/6Nx marmosets showed a stable CRF condition for a long time and some characteristic disorders similar to those observed in CRF patients. These diagnostic aspects might be a species-specific anatomical and physiological signature, reflecting the nutritional condition. The CRF model using 5/6Nx marmosets might become a useful method of evaluating the unique mechanism of CRF development.

Spontaneous Malignant T Cell Lymphoma in a Young Male Common Marmoset (Callithrix jacchus).

We histopathologically and immunohistochemically investigated a case of malignant lymphoma that spontaneously developed in a male common marmoset at two years of age. Beginning at two years four months of age, the animal had an enlargement of the submandibular and inguinal lymph nodes, small subcutaneous nodules near the right breast and an approximately fivefold increase in peripheral lymphocyte count compared with the previous examination value. The postmortem findings at two years eight months of age showed lymphadenopathy with enlargement of the thymus and spleen. Small- to intermediate-sized neoplastic lymphocytes had diffusely proliferated in the enlarged nodes. The neoplastic cells were pleomorphic and had irregularly shaped nuclei. The nuclear chromatin staining revealed hyperchromatism in the small-sized cells, and the intermediate-sized cells exhibited vesicular staining. An immunohistochemical examination indicated that the neoplastic lymphocytes were positive for CD3 and negative for CD20, thus suggesting that they had originated from T cells. In addition, the proliferation of high endothelial venules and reactive epithelioid histiocytes was observed. Scattered tingible body-laden macrophages were infrequently detected. Neoplastic lymphocytes were also observed in the thymus, spleen, heart, lungs, liver, kidneys, adrenal glands and femoral and sternal bone marrow. This malignant lymphoma in a young male common marmoset was considered to fit the category of "peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS)" according to the new WHO system of classification.

Histopathological, immunohistochemical and ultrastructural studies of a renal mesenchymal tumor in a young beagle dog.

A 15-month-old male beagle dog used in a toxicity study had a primary renal mesenchymal tumor. Macroscopically, the tumor was a gray-white mass which was found in the right kidney, and extended from the capsule to a position slightly compressing the medulla. Microscopically, most of the tumor cells showed a myxoid pattern, in which the matrix was positive for alcian blue staining. In the other parts of the tumor, a fascicular and wavy pattern was observed, and the matrix was full of collagen fibrils. Immunohistochemically, tumor cells were positive for vimentin and fibronectin, and negative for cytokeratin, desmin, α-smooth muscle actin, Von Willebrand factor, cyclooxigenase-2 and myelin basic protein. As a result, we diagnosed this case to be a renal mesenchymal tumor. Based on the microscopic findings, interstitial characteristics and immunohistochemical features, the present case was classified as a congenital mesoblastic tumor.

Spontaneous Adenosquamous Carcinoma with Rapid Growth and EMT-like Changes in the Mammary Gland of a Young Adult Female BALB/c Mouse.

This study histopathologically and immunohistochemically investigated a spontaneously occurring single mass subcutaneously located in the left lower abdomen of a female BALB/cAJcl-nu/+ mouse at 10 weeks of age. The mass was about 20 × 15 × 10 mm in size after formalin fixation; nevertheless, it was not detected by clinical observations at 9 weeks of age. H&E staining revealed the tumor origin was epithelial and probably arose from the mammary gland, and the tumor cells demonstrated a squamous, acinar or polyhedral/basal pattern. A cell kinetics analysis revealed that many of the tumor cells of the squamous, acinar or polyhedral/basal component were positive for PCNA and cyclin D1, although there were a few of TUNEL-positive tumor cells in all of the components. An epithelial/mesenchymal analysis demonstrated that most of the tumor cells of the squamous and acinar components contained keratin and E-cadherin; however, most of the tumor cells of the polyhedral/basal component were less or very weakly positive for these markers. The tumor cells of the squamous component were negative for vimentin and SMA; however, many of the tumor cells of the polyhedral/basal component exhibited vimentin. In addition, expression of SMA was confirmed in some tumor cells of the acinar and basal components. Based on the microscopic and immunohistochemical characterizations, the tumor was diagnosed to be adenosquamous carcinoma that originated from the mammary gland with rapid growth, and the tumor cells demonstrated epithelial-mesenchymal transition-like changes.