The addition of an extended lymphadenectomy and retroperitoneal soft-tissue clearance to a pancreatoduodenal resection does not significantly increase morbidity and mortality rates. Although the overall survival rate does not differ in the two groups, there appears to be a trend toward longer survival in node positive patients treated with an extended rather than a standard lymphadenectomy.

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.Gastroesophageal and pancreatic cancers are among the malignancies with the highest unmet medical needs (1). Gastric cancer is the second leading cause of cancer death worldwide. In 2002, f1.4 million people worldwide developed gastroesophageal cancers and 1.1 million died (2). Esophageal cancer incidence has increased in recent decades, coinciding with a shift in histologic type and primary tumor location. Adenocarcinoma of the esophagus is now more prevalent than squamous cell carcinoma in the United States and Western Europe, with most tumors located in the distal esophagus (3).The overall 5-year survival rates for gastroesophageal cancers are 20% to 25% despite the aggressiveness of established standard treatments associated with substantial side effects (4, 5). For pancreatic cancer, there is an even greater medical need. Due to the advanced state of the disease at the time of diagnosis, the prognosis is extremely poor, with median survival times of less than 6 months and a 5-year survival rate of <5.5%. The lack of a major benefit from the various newergeneration combination chemotherapy regimens for these cancers has stimulated research into the use of targeted agents, such as small molecule -based kinase inhibitors and monoclonal antibodies (mAb; ref. 6). However, mAbs, such as bevacizumab, cetuximab, and trastuzumab...

Background: Claudin 18.2 (CLDN18.2) is contained within normal gastric mucosa epithelial tight junctions; upon malignant transformation, CLDN18.2 epitopes become exposed. Zolbetuximab, a chimeric monoclonal antibody, mediates specific killing of CLDN18.2-positive cells through immune effector mechanisms. Patients and methods: The FAST study enrolled advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients (aged 18 years) with moderate-to-strong CLDN18.2 expression in 40% tumour cells. Patients received first-line epirubicin þ oxaliplatin þ capecitabine (EOX, arm 1, n ¼ 84) every 3 weeks (Q3W), or zolbetuximab þ EOX (loading dose, 800 mg/m 2 then 600 mg/m 2 Q3W) (arm 2, n ¼ 77). Arm 3 (exploratory) was added after enrolment initiation (zolbetuximab þ EOX 1000 mg/m 2 Q3W, n ¼ 85). The primary endpoint was progression-free survival (PFS) and overall survival (OS) was a secondary endpoint. Results: In the overall population, both PFS [hazard ratio (HR) ¼ 0.44; 95% confidence interval (CI), 0.29-0.67; P < 0.0005] and OS (HR ¼ 0.55; 95% CI, 0.39-0.77; P < 0.0005) were significantly improved with zolbetuximab þ EOX (arm 2) compared with EOX alone (arm 1). This significant PFS benefit was retained in patients with moderate-tostrong CLDN18.2 expression in 70% of tumour cells (HR ¼ 0.38; 95% CI, 0.23-0.62; P < 0.0005). Significant improvement in PFS was also reported in the overall population of arm 3 versus arm 1 (HR ¼ 0.58; 95% CI, 0.39-0.85; P ¼ 0.0114) but not in high CLDN18.2-expressing patients; no significant improvement in OS was observed in either population. Most adverse events (AEs) related to zolbetuximab þ EOX (nausea, vomiting, neutropenia, anaemia) were grade 1-2. Grade 3 AEs showed no substantial increases overall (zolbetuximab þ EOX versus EOX alone). Conclusions: In advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients expressing CLDN18.2, adding zolbetuximab to first-line EOX provided longer PFS and OS versus EOX alone. Zolbetuximab þ EOX was generally tolerated and AEs were manageable. Zolbetuximab 800/600 mg/m 2 is being evaluated in phase III studies based on clinical benefit observed in the overall population and in patients with moderate-to-strong CLDN18.2 expression in 70% of tumour cells.

BackgroundClaudin 18.2 (CLDN18.2) is physiologically confined to gastric mucosa tight junctions; however, upon malignant transformation, perturbations in cell polarity lead to CLDN18.2 epitopes being exposed on the cancer cell surface. The first-in-class monoclonal antibody, zolbetuximab (formerly known as IMAB362), binds to CLDN18.2 and can induce immune-mediated lysis of CLDN18.2-positive cells.Patients and methodsPatients with advanced gastric, gastro-oesophageal junction (GEJ) or oesophageal adenocarcinomas with moderate-to-strong CLDN18.2 expression in ≥50% of tumour cells received zolbetuximab intravenously every 2 weeks for five planned infusions. At least three patients were enrolled in two sequential cohorts (cohort 1300 mg/m2; cohort 2600 mg/m2); additional patients were enrolled into a dose-expansion cohort (cohort 3600 mg/m2). The primary end point was the objective response rate [ORR: complete and partial response (PR)]; secondary end points included clinical benefit [ORR+stable disease (SD)], progression-free survival, safety/tolerability, and zolbetuximab pharmacokinetic profile.ResultsFrom September 2010 to September 2012, 54 patients were enrolled (cohort 1, n = 4; cohort 2, n = 6; cohort 3, n = 44). Three patients in cohort 1 and 25 patients in cohorts 2/3 received at least 5 infusions. Antitumour activity data were available for 43 patients, of whom 4 achieved PR (ORR 9%) and 6 (14%) had SD for a clinical benefit rate of 23%. In a subgroup of patients with moderate-to-high CLDN18.2 expression in ≥70% of tumour cells, ORR was 14% (n = 4/29). Treatment-related adverse events occurred in 81.5% (n = 44/54) patients; nausea (61%), vomiting (50%), and fatigue (22%) were the most frequent.ConclusionsZolbetuximab monotherapy was well tolerated and exhibited antitumour activity in patients with CLDN18.2-positive advanced gastric or GEJ adenocarcinomas, with response rates similar to those reported for single-agent targeted agents in gastric/GEJ cancer trials.ClinicalTrials.gov numberNCT01197885.

In the mid 1990s, the hypothesis emerged that the upregulation or re-expression of a telomere-synthesising ribonucleoprotein, called telomerase, is a critical event responsible for continuous tumour cell growth. In contrast to normal cells, in which gradual mitosis-related erosion of telomeres eventually limits replicative life span, tumour cells have telomerase and show no loss of these chromosomal ends. These data suggest that telomere stabilisation may be required for cells to escape replicative senescence and to proliferate indefinitely. Because of the close association between telomerase and malignancy, both pathologists and clinicians expect this molecule to be a useful malignancy-marker and a new therapeutic target. This review focuses on the components of the human telomere and of the human telomerase enzyme. A synopsis of reports studying the clinical-diagnostic value of telomere length measurements, of telomerase activity analyses and of the in situ telomerase detection is given. Finally, a summary of recent experimental work that sheds new light on the biological role of this fascinating molecule is presented.

ClinicalTrials.gov, Identifier NCT00909025.

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. [Cancer Res 2008;68(9):3458-66]

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 5 24), primary lesions (N 5 202), metastases (N 5 84) and intra-individually matched samples (N 5 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 0-31) 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 5 95) with staining intensities of 21. NEN were positive in 20% of cases (all 21). 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.Pancreatic ductal adenocarcinoma (PDAC), representing >80% of all pancreatic neoplasms, is the seventh most frequent cancer in Europe and is the fourth most frequent cause of cancer related deaths in the European Union (EU).1-3 The prevalence of pancreatic neoplasms is 1-5/10,000 in both, the EU and the United States. 4,5 In contrast to all major cancers, however, the mortality rate of PDAC is expected to increase further. 6 No effective screening programs for early detection of pancreatic neoplasms are available and patients lack specific clinical symptoms at early stages. Thus, most PDAC patients are diagnosed at an advanced stage of the disease and are not suitable for resection with curative intent. For systemic palliative treatment cytotoxic agents are administered. The majority of patients are treated with gemcitabine, whereas patients with a good performance status undergo polychemotherapy with 5-FU/irinotecan/oxaliplatin (FOLFORINOX).3,7 Chemosensitivity of PDAC is moderate 8 and targeted therapeutics are of high interest. Although various compounds have been tested, only erlotinib, an epidermal growth factor receptor tyrosine kinase inhibitor, received approval by the European Medicines Agency (EMA) and Food and Drug Administration (FDA) for the treatment of patients with metastatic disease in combination with gemcitabine. The ...