Prognostic image-based quantification of CD8CD103 T cell subsets in high-grade serous ovarian cancer patients

CD103-positive tissue resident memory-like CD8+ T cells (CD8CD103 TRM) are associated with improved prognosis across malignancies, including high-grade serous ovarian cancer (HGSOC). However, whether quantification of CD8, CD103 or both is required to improve existing survival prediction and whether all HGSOC patients or only specific subgroups of patients benefit from infiltration, remains unclear. To address this question, we applied image-based quantification of CD8 and CD103 multiplex immunohistochemistry in the intratumoral and stromal compartments of 268 advanced-stage HGSOC patients from two independent clinical institutions. Infiltration of CD8CD103 immune cell subsets was independent of clinicopathological factors. Our results suggest CD8CD103 TRM quantification as a superior method for prognostication compared to single CD8 or CD103 quantification. A survival benefit of CD8CD103 TRM was observed only in patients treated with primary cytoreductive surgery. Moreover, survival benefit in this group was limited to patients with no macroscopic tumor lesions after surgery. This approach provides novel insights into prognostic stratification of HGSOC patients and may contribute to personalized treatment strategies in the future.

Development of a radioiodinated apoptosis-inducing ligand, rhTRAIL, and a radiolabelled agonist TRAIL receptor antibody for clinical imaging studies

BACKGROUND AND PURPOSE

The TNF-related apoptosis inducing ligand (TRAIL) induces apoptosis through activation of the death receptors, TRAIL-R1 and TRAIL-R2. Recombinant human (rh) TRAIL and the TRAIL-R1 directed monoclonal antibody mapatumumab are currently clinically evaluated as anticancer agents. The objective of this study was to develop radiopharmaceuticals targeting the TRAIL-R1, suitable for clinical use to help understand and predict clinical efficacy in patients.

EXPERIMENTAL APPROACH

rhTRAIL was radioiodinated with (125) I, and conjugated mapatumumab was radiolabelled with (111) In. The radiopharmaceuticals were characterized, their in vitro stability and death receptor targeting capacities were determined and in vivo biodistribution was studied in nude mice bearing human tumour xenografts with different expression of TRAIL-R1.

KEY RESULTS

Labelling efficiencies, radiochemical purity, stability and binding properties were optimized for the radioimmunoconjugates. In vivo biodistribution showed rapid renal clearance of [(125) I]rhTRAIL, with highest kidney activity at 15 min and almost no detectable activity after 4 h. Activity rapidly decreased in almost all organs, except for the xenografts. Radiolabelled mapatumumab showed blood clearance between 24 and 168 h and a reduced decrease in radioactivity in the high receptor expression xenograft.

CONCLUSIONS AND IMPLICATIONS

rhTRAIL and mapatumumab can be efficiently radiolabelled. The new radiopharmaceuticals can be used clinically to study pharmacokinetics, biodistribution and tumour targeting, which could support evaluation of the native targeted agents in phase I/II trials.

Development of radiolabeled mapatumumab and imaging in solid tumor patients who are treated with gemcitabine, cisplatin, and mapatumumab

e14521

Background: Mapatumumab is a fully human agonistic monoclonal antibody (mAb) to the tumor necrosis factor-related apoptosis-inducing ligand receptor 1 (TRAIL-R1). Mapatumumab combined with gemcitabine and cisplatin increased cytotoxicity in preclinical models and was safe in a phase 1 study. To study its biodistribution, 111Indium (111In) labeled mapatumumab was developed for γ-camera imaging and tested in mice. Subsequently, 111In-mapatumumab scintigraphy was performed in patients (pts). Methods: Mapatumumab was labeled with 111In. Labeling efficiency, radiochemical purity, stability and binding properties were determined in vitro. Biodistribution was studied at multiple time points in nude mice bearing human xenografts (SKBR3 or SW948). Tissue activity was expressed as % injected dose/gram tissue (%ID/g). In a feasibility study, gemcitabine 1250 mg/m2 IV on days 1 and 8, cisplatin 80 mg/m2 IV and mapatumumab 20 mg/kg on day 1 was administered to advanced solid tumor pts every 21 days. In cycles 1 and 3, pts underwent γ-camera imaging directly, and at day 1, 3, and 6 after 150 MBq 111In-mapatumumab IV (planar and single-photon emission computed tomography (SPECT)). Results: Labeling efficiency was 92.0% and radiochemical purity 96.0%. 111In-mapatumumab was stable in serum for 1 week at 37°C and specific TRAIL-R1 binding was maintained after labeling. In mice, high uptake was seen in liver (8.14 ± 0.75 %ID/g), kidneys (16.30 ± 1.75 %ID/g), spleen (7.25 ± 2.64 %ID/g) and bone (5.68 ± 1.31 %ID/g), with a maximum 24–72 hours (h) after tracer injection. Maximum uptake in the xenografts was observed after 72 h (7.55 ± 3.54 %ID/g for SKBR3 and 6.21 ± 2.03 %ID/g for SW948). Five pts have been enrolled in the ongoing clinical study. Known tumor lesions (by CT-scan) showed variable tracer uptake in 3 pts, while within pts not all known tumor lesions were positive on SPECT. Conclusions: Mapatumumab can be efficiently radiolabeled for clinical use. Preliminary results show that mapatumumab scintigraphy identifies some but not all tumor lesions in pts. This is the first demonstration that mAb targeting a TRAIL-R distributes to tumor tissues in patients and could potentially guide mapatumumab therapy.

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The clinical trail of TRAIL

The naturally occurring tumour necrosis factor related apoptosis-inducing ligand (TRAIL) induces apoptosis through two death receptors, death receptor 4 (DR4) and death receptor 5 (DR5), that are expressed on the cell membrane. Binding of the ligand to the death receptors leads to activation of the extrinsic apoptosis pathway. Chemotherapy on the other hand stimulates the intrinsic apoptosis pathway via activation of p53 in response to cellular damage. Many cancer cells have mutations in p53 causing resistance to chemotherapy-induced apoptosis. Concomitant signalling through the extrinsic pathway may overcome this resistance. Moreover, enthusiasm for TRAIL as an anticancer agent is based on the demonstration of rhTRAIL-induced selective cell death in tumour cells and not in normal cells. In this review, we provide an overview of the TRAIL pathway, the physiological role of TRAIL and the factors regulating TRAIL sensitivity. We also discuss the clinical development of novel agents, i.e. rhTRAIL and agonistic antibodies, that activate the death receptors.

Molecular prognostic markers in ovarian cancer: toward patient-tailored therapy

In ovarian cancer the ceiling seems to be reached with chemotherapeutic drugs. Therefore a paradigm shift is needed. Instead of treating all patients according to standard guidelines, individualized molecular targeted treatment should be aimed for. This means that molecular profiles of the distinct ovarian cancer subtypes should be established. Until recently, most studies trying to identify molecular targets were single-marker studies. The prognostic role of key components of apoptotic and prosurvival pathways such as p53, EGFR, and HER2 has been extensively studied because resistance to chemotherapy is often caused by failure of tumor cells to go into apoptosis. However, it is more than likely that different ovarian cancer subtypes with extensive molecular heterogeneity exist. Therefore, exploration of the potential of specific tumor-targeted therapy, based on expression of a prognostic tumor profile, may be of interest. Recently, new profiling techniques, such as DNA and protein microarrays, have enabled high-throughput screening of tumors. In this review an overview of the current status of prognostic marker and molecular targeting research in ovarian cancer, including microarray studies, is presented.

Molecular prognostic markers in ovarian cancer: toward patient-tailored therapy

In ovarian cancer the ceiling seems to be reached with chemotherapeutic drugs. Therefore a paradigm shift is needed. Instead of treating all patients according to standard guidelines, individualized molecular targeted treatment should be aimed for. This means that molecular profiles of the distinct ovarian cancer subtypes should be established. Until recently, most studies trying to identify molecular targets were single-marker studies. The prognostic role of key components of apoptotic and prosurvival pathways such as p53, EGFR, and HER2 has been extensively studied because resistance to chemotherapy is often caused by failure of tumor cells to go into apoptosis. However, it is more than likely that different ovarian cancer subtypes with extensive molecular heterogeneity exist. Therefore, exploration of the potential of specific tumor-targeted therapy, based on expression of a prognostic tumor profile, may be of interest. Recently, new profiling techniques, such as DNA and protein microarrays, have enabled high-throughput screening of tumors. In this review an overview of the current status of prognostic marker and molecular targeting research in ovarian cancer, including microarray studies, is presented.