Spreading Pattern and Tissue Response to Hyaluronic Acid Gel Injections in the Subcutis: Ultrasound Videos, Ultrasound Measurements, and Histology.

BACKGROUND: Despite the popularity of hyaluronic acid (HA) filler treatments, few publications focus on their effects on adipose tissue. OBJECTIVES: The authors assessed the deposition pattern in the subcutis of injected HA, the tissue response at short and intermediate term, and the effects of remodeling the filler by strong finger pressure immediately after the treatment. METHODS: Two brands, specifically developed by the industry for deep injection, were compared. The gels were injected subcutaneously in 5 candidates for abdominoplasty or breast reduction, in the area of excision, 6 to 98 days before surgery. Ultrasound measurements and films were compared with postoperative histological findings. Tissue response was scored semi-quantitatively. RESULTS: Real-time ultrasound showed a slightly different deposition pattern of the 2 brands. Histologically, both were present in large pools of the same magnitude and looked the same. Linear retrograde injection sometimes resulted in a globular deposit due to elastic recoil of septae. After remodeling and over time, HA deposits became difficult to detect by ultrasound. Firm remodeling of the tissue immediately after injection or time had no significant effect on filler spread or tissue response. Except for 1 zone of granuloma formation, tolerance for both fillers was good. CONCLUSIONS: HA deposition in adipose tissue occurs in much larger pools than in the dermis. Ultrasound examination is useful during and immediately after the injection but less reliable after filler remodeling or over time. Filler deposition can be less precise, and reshaping by finger pressure can have less effect than expected.

Claudin 18.2 is a target for IMAB362 antibody in pancreatic neoplasms.

The majority of pancreatic neoplasms are characterized by a generally lethal progress within a short period of time after primary diagnosis and the mortality of patients is expected to increase further. Due to lack of efficient screening programs and moderate response to treatments, novel compounds for treatment are needed. We investigated the CLDN18.2 expression in affected patients as in vitro feasibility study for a potential treatment with the novel antibody IMAB362. Therefore, we analyzed the expression of CLDN18.2 in normal pancreatic tissues (N = 24), primary lesions (N = 202), metastases (N = 84) and intra-individually matched samples (N = 48) of patients with pancreatic ductal adenocarcinoma (PDAC), neuroendocrine neoplasia (NEN) and acinar cell carcinoma. A standardized method for evaluation by immunohistochemistry was developed. The specific staining was evaluated by two independent raters and analysis of staining intensities (range 0-3+) and relative proportions of tumor cells were performed. One hundred three (59.2%) samples of primary PDAC were found positive. The vast majority of positive samples were characterized to highly express CLDN18.2: 54.6% (N = 95) with staining intensities of ≥ 2+. NEN were positive in 20% of cases (all ≥ 2+). Metastases of pancreatic neoplasms were also frequently found positive with comparable high rates (69.4% of lymph node and 65.7% of liver metastases). The rate of CLDN18.2 positivity is high in pancreatic neoplasms whereby the expression is not limited to the primaries but is also maintained upon metastasis. Thus, a considerable number of patients with pancreatic neoplasms would be in principle eligible for a CLDN18.2-targeting approach.

Claudin-18 splice variant 2 is a pan-cancer target suitable for therapeutic antibody development.

PURPOSE: Antibody-based cancer therapies have emerged as the most promising therapeutics in oncology. The purpose of this study was to discover novel targets for therapeutic antibodies in solid cancer. EXPERIMENTAL DESIGN: We combined data mining and wet-bench experiments to identify strictly gastrocyte lineage-specific cell surface molecules and to validate them as therapeutic antibody targets. RESULTS: We identified isoform 2 of the tight junction molecule claudin-18 (CLDN18.2) as a highly selective cell lineage marker. Its expression in normal tissues is strictly confined to differentiated epithelial cells of the gastric mucosa, but it is absent from the gastric stem cell zone. CLDN18.2 is retained on malignant transformation and is expressed in a significant proportion of primary gastric cancers and the metastases thereof. In addition to its orthotopic expression, we found frequent ectopic activation of CLDN18.2 in pancreatic, esophageal, ovarian, and lung tumors, correlating with distinct histologic subtypes. The activation of CLDN18.2 depends on the binding of the transcription factor cyclic AMP-responsive element binding protein to its unmethylated consensus site. Most importantly, we were able to raise monoclonal antibodies that bind to CLDN18.2 but not to its lung-specific splice variant and recognize the antigen on the surface of cancer cells. CONCLUSIONS: Its highly restricted expression pattern in normal tissues, its frequent ectopic activation in a diversity of human cancers, and the ability to specifically target this molecule at the cell surface of tumor cells qualify CLDN18.2 as a novel, highly attractive pan-cancer target for the antibody therapy of epithelial tumors.

In silico strategy for detection of target candidates for antibody therapy of solid tumors.

In contrast to earlier attempts for the identification of target candidates suitable for monoclonal antibody (mAb) based cancer therapies we concentrated on highly selective lineage-specific genes additionally preserved or even overexpressed in orthotopic cancers. In a script aided workflow we reduced all human entries of the RefSeq mRNA database to those encoding transmembrane domain bearing gene products and subjected them to BLAST analysis against the human EST database. All BLAST results were validated in a gene centric way allowing two types of data curation prior to expression profiling of matching ESTs in selected healthy tissues: (i) exclusion of questionable ESTs arising e.g. from genomic contamination and (ii) elimination of erroneously predicted mRNAs as well as transcripts with only weak EST coverage. The impact of such stringent input control on accuracy of prediction is underlined by RT-PCR confirmation of predicted tissue distribution patterns for a number of selected candidates.

A phase I dose-escalation study of IMAB362 (Zolbetuximab) in patients with advanced gastric and gastro-oesophageal junction cancer.

INTRODUCTION: IMAB362 (Zolbetuximab) is a chimeric monoclonal antibody that binds to Claudin-18.2, a target antigen specific to cancer cells. In vitro, IMAB362 mediates cell death through antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity; thus, IMAB362 may serve as a potent, targeted immunotherapeutic agent. METHODS: This first-in-human phase I study enroled adult patients (N = 15) with advanced gastric or gastro-oesophageal junction cancer into five sequential single dose-escalation cohorts (33, 100, 300, 600, and 1000 mg/m2) following a 3 + 3 design. Safety/tolerability, including determination of maximum tolerated dose and recommended phase II dose, were the primary objectives; secondary objectives included assessment of the IMAB362 pharmacokinetic profile, immunogenicity, and antitumour activity (assessed by Response Evaluation Criteria in Solid Tumors v1.0). RESULTS: IMAB362 was generally well tolerated at all doses, with gastrointestinal toxicities being the most commonly observed treatment-related adverse events. As dose-limiting toxicity was not observed within 4 weeks of treatment, a maximum tolerated dose was not established. The pharmacokinetic profile of IMAB362 appeared to be proportional across the dose range; and mean half-life ranged from 13 to 24 d. While most patients showed progressive disease at weeks 4-5 after a single intravenous IMAB362 infusion, one patient in the 600 mg/m2 dose group achieved and maintained stable disease for approximately 2 months postinfusion. CONCLUSIONS: Findings from this study demonstrate that IMAB362 is generally well tolerated and support further evaluation in patients with gastric/gastro-oesophageal junction cancer. CLINICAL TRIAL REGISTRY: ClinicalTrials.gov, Identifier NCT00909025.

Expression profiling of autoimmune regulator AIRE mRNA in a comprehensive set of human normal and neoplastic tissues.

Defects in the autoimmune regulator (AIRE) gene cause the monogenic autoimmune disease autoimmune polyendocrinopathy syndrome type 1 (APS-1), which is characterized by a loss of self-tolerance to multiple organs. In concordance with its role in immune tolerance, AIRE is strongly expressed in medullary thymic epithelial cells (mTECs). Data on mechanisms controlling AIRE activation and the expression of this gene in other tissues are fragmentary and controversial. We report here AIRE mRNA expression profiling of a large set of normal human tissues and cells, tumor specimen and methylation deficient cell lines. On this broad data basis we found that AIRE mRNA expression is confined to mTECs in thymus and to lymph node tissue and that DNA hypomethylation contributes to transcriptional control of this gene.

Prostatic Leiomyoma: A Case Report.

A pure leiomyoma of the prostate is a rare tumor. Less than 30 cases about prostatic leiomyoma have been reported. Pathologic anatomy examination is the only medium for definitive diagnosis and is important to rule out malignancies such as leiomyosarcoma. We describe an accidental finding of a tumor in the right prostate lobe of a 54 year old man, who was diagnosed with prostatic leiomyoma and treated with open radical prostatectomy.

Functional TCR retrieval from single antigen-specific human T cells reveals multiple novel epitopes.

The determination of the epitope specificity of disease-associated T-cell responses is relevant for the development of biomarkers and targeted immunotherapies against cancer, autoimmune, and infectious diseases. The lack of known T-cell epitopes and corresponding T-cell receptors (TCR) for novel antigens hinders the efficient development and monitoring of new therapies. We developed an integrated approach for the systematic retrieval and functional characterization of TCRs from single antigen-reactive T cells that includes the identification of epitope specificity. This is accomplished through the rapid cloning of full-length TCR-α and TCR-ß chains directly from single antigen-specific CD8(+) or CD4(+) T lymphocytes. The functional validation of cloned TCRs is conducted using in vitro-transcribed RNA transfer for expression of TCRs in T cells and HLA molecules in antigen-presenting cells. This method avoids the work and bias associated with repetitive cycles of in vitro T-cell stimulation, and enables fast characterization of antigen-specific T-cell responses. We applied this strategy to viral and tumor-associated antigens (TAA), resulting in the retrieval of 56 unique functional antigen-specific TCRs from human CD8(+) and CD4(+) T cells (13 specific for CMV-pp65, 16 specific for the well-known TAA NY-ESO-1, and 27 for the novel TAA TPTE), which are directed against 39 different epitopes. The proof-of-concept studies with TAAs NY-ESO-1 and TPTE revealed multiple novel TCR specificities. Our approach enables the rational development of immunotherapy strategies by providing antigen-specific TCRs and immunogenic epitopes.

Claudin-18 gene structure, regulation, and expression is evolutionary conserved in mammals.

Claudin-18 isoform 2 (CLDN18.2) is one of the few members of the human claudin family of tight junction molecules with strict restriction to one cell lineage. The objective of the current study was to compare molecular structure and tissue distribution of this gastrocyte specific molecule in mammals. We show here that the CLDN18.2 protein sequence is highly conserved, in particular with regard to functionally relevant domains in mouse, rat, rabbit, dog, monkey and human and also in lizards. Moreover, promoter regions of orthologs are highly homologous, including the binding site of the transcription factor cyclic AMP-responsive element binding protein (CREB), which is known to regulate activation of human CLDN18.2. Employing RT-PCR and immunohistochemistry, we found that, analogous to the human gene, all orthologous CLDN18.2 transcripts and proteins are exclusively expressed in differentiated gastric cells. Gene structure, promoter elements and RNA expression pattern of the lung-tissue specific Claudin-18 isoform 1 (CLDN18.1) as well, are homologous across species. These findings exemplify phylogenetic conservation of lineage-specific members of a multigene family. Given that CLDN18.2 is a novel drug target candidate, our data is also relevant for drug development as it reveals all six investigated mammalian species as suitable models for testing safety of CLDN18.2 targeting regimen.

MS4A12 is a colon-selective store-operated calcium channel promoting malignant cell processes.

Using a data mining approach for the discovery of new targets for antibody therapy of colon cancer, we identified MS4A12, a sequence homologue of CD20. We show that MS4A12 is a cell surface protein. Expression analysis and immunohistochemistry revealed MS4A12 to be a colonic epithelial cell lineage gene confined to the apical membrane of colonocytes with strict transcriptional repression in all other normal tissue types. Expression is maintained upon malignant transformation in 63% of colon cancers. Ca(2+) flux analyses disclosed that MS4A12 is a novel component of store-operated Ca(2+) entry in intestinal cells. Using RNAi-mediated gene silencing, we show that loss of MS4A12 in LoVo colon cancer cells attenuates epidermal growth factor receptor-mediated effects. In particular, proliferation, cell motility, and chemotactic invasion of cells are significantly impaired. Cancer cells expressing MS4A12, in contrast, are sensitized and respond to lower concentrations of epidermal growth factor. In summary, these findings have implications for both the physiology of colonic epithelium as well as for the biology and treatment of colon cancer.

Expression of multiple epigenetically regulated cancer/germline genes in nonsmall cell lung cancer.

Cancer/germline (CG) antigens represent promising targets for widely applicable mono- and multiantigen cancer vaccines for nonsmall cell lung cancer (NSCLC). Since little is known about their composite expression in this tumor type, we analyzed 7 CG genes (MAGE-A3, NY-ESO-1, LAGE-1, BRDT, HOM-TES-85, TPX-1 and LDHC) in 102 human NSCLC specimens. About 81% of NSCLC express at least 1 and half of the specimen at least 2 CG genes. Activation of most of these genes occurs more frequently in squamous cell cancer than in adenocarcinomas. Even though we found all genes but one to be regulated by genomic methylation, not all of them are co-expressed. In particular, combining CG genes not localized on the X-chromosome may provide effective treatment for an extended number of patients.