VISTA Regulates the Development of Protective Antitumor Immunity

V-domain Ig suppressor of T-cell activation (VISTA) is a novel negative checkpoint ligand that is homologous to PD-L1 and suppresses T-cell activation. This study demonstrates the multiple mechanisms whereby VISTA relieves negative regulation by hematopoietic cells and enhances protective antitumor immunity. VISTA is highly expressed on myeloid cells and Foxp3(+)CD4(+) regulatory cells, but not on tumor cells within the tumor microenvironment (TME). VISTA monoclonal antibody (mAb) treatment increased the number of tumor-specific T cells in the periphery and enhanced the infiltration, proliferation, and effector function of tumor-reactive T cells within the TME. VISTA blockade altered the suppressive feature of the TME by decreasing the presence of monocytic myeloid-derived suppressor cells and increasing the presence of activated dendritic cells within the tumor microenvironment. In addition, VISTA blockade impaired the suppressive function and reduced the emergence of tumor-specific Foxp3(+)CD4(+) regulatory T cells. Consequently, VISTA mAb administration as a monotherapy significantly suppressed the growth of both transplantable and inducible melanoma. Initial studies explored a combinatorial regimen using VISTA blockade and a peptide-based cancer vaccine with TLR agonists as adjuvants. VISTA blockade synergized with the vaccine to effectively impair the growth of established tumors. Our study therefore establishes a foundation for designing VISTA-targeted approaches either as a monotherapy or in combination with additional immune-targeted strategies for cancer immunotherapy.

Characterization of twenty-five ovarian tumour cell lines that phenocopy primary tumours

Currently available human tumour cell line panels consist of a small number of lines in each lineage that generally fail to retain the phenotype of the original patient tumour. Here we develop a cell culture medium that enables us to routinely establish cell lines from diverse subtypes of human ovarian cancers with >95% efficiency. Importantly, the 25 new ovarian tumour cell lines described here retain the genomic landscape, histopathology and molecular features of the original tumours. Furthermore, the molecular profile and drug response of these cell lines correlate with distinct groups of primary tumours with different outcomes. Thus, tumour cell lines derived using this methodology represent a significantly improved platform to study human tumour pathophysiology and response to therapy.

Post-traumatic malunion of the distal radius treated with autologous costal cartilage graft: a technical note on seven cases

Seven cases of post-traumatic intra-articular malunion of the distal radius treated using costal cartilage graft with a minimum follow-up of 2 years are reported. Location of the articular defect was dorsal in two cases and volar in the others. The approach (dorsal or volar) depended on the main location of the defect. A costal cartilage graft harvested on the eighth rib was implanted in a trough created at the epiphysis metaphyseal junction. This trough removed the defective area on the distal radius articular surface. A plate or wire fixation was used to stabilize in place the graft. Plaster cast wear was prescribed for 3 months in the first case and for 1 month in the other cases following joint reconstruction. No complications were observed. Union was achieved in all seven cases. Graft integration and viability were evaluated with MRI and biopsy. At the longest follow-up, the functional results were excellent in the first (youngest) case (male, 22 years old) in whom motion and grasp were similar to the contralateral side. In the other cases of malunion, the patients were pain-free in daily activities with a functional wrist score of 72/100 (range, 54-82) and a DASH score of 38.3 (range, 22.5-51.7). Only the case with a septic problem failed, with pain reported at follow-up. Reconstruction of a partially destroyed articular surface using a costal graft is reliable and allows filling and resurfacing an articular cartilage void. Although costal cartilage graft is currently used in maxillofacial surgery, this is the first report in post-traumatic osteoarthritis secondary to intra-articular malunion.

LEVEL OF EVIDENCE

Level IV.

Efficacy of indefinite chronic oral antimicrobial suppression for prosthetic joint infection in the elderly: a comparative study

BACKGROUND

During prosthetic joint infection (PJI), surgical management is sometimes impossible and indefinite chronic oral antimicrobial suppression (ICOAS) may be the only option. The outcomes of elderly patients who benefited from ICOAS with strictly palliative intent were evaluated.

METHODS

A national retrospective cohort study was performed in France, involving patients aged >75 years with a PJI who were managed with planned life-long ICOAS from 2009 to 2014. Patients who experienced an event were compared to those who did not. An event was defined as a composite outcome in patients undergoing ICOAS, including local or systemic progression of the infection, death, or discontinuation of antimicrobial therapy because of an adverse drug reaction.

RESULTS

Twenty-one patients were included, with a median age of 85 years (interquartile range 81-88 years). Eight of the 21 patients experienced an event: one had an adverse drug reaction, three had systemic progression of sepsis, and two had local progression. Two of the 21 patients died. No death was related to ICOAS or infection. There was no significant difference between the population with an event and the population free of an event with regard to demographic, clinical, and microbiological characteristics (p>0.05).

CONCLUSIONS

ICOAS appeared to be an effective and safe option in this cohort.

Management of forearm bone loss with induced membrane technique

There are very few published studies describing the treatment of segmental bone defects of the forearm using the induced membrane technique. The objectives of this study were to evaluate the time to bone union, the function of the joints above and below the treated bone segment and the patients' quality of life over the long-term. We performed a retrospective study in all patients treated by the induced membrane for a forearm bone defect over at 13-year period. Demographics, bone union, complications, functional outcomes and occupational status were collected. Six patients were included: 2 posttraumatic injuries, 1 osteomyelitis, 1 septic arthritis, 1 aseptic nonunion, 1 tumor. The average defect length was 64mm (48-110). All defects were treated with internal fixation. Bone graft was harvested from the iliac crest in two patients, the femur (using the Reamer Irrigator Aspirator technique) in three patients and the radius in one patient. Five patients achieved bone union after a mean of 4months (3-6). Three complications were observed: 1 radioulnar instability, 1 infection of the fixation device, 1 abscess. At an average 8½ years' follow-up, the pain level on the VAS was 0.6 (0-3), the Mayo Elbow Performance Score was 98 (90-100), the Herzberg score was 108 (85.6-140) and the QuickDASH was 14.9 (2.7-35). All patients returned to work. Using the induced membrane technique avoids the complications associated with vascularized autograft and yields good functional outcome and quality of life.

A Syngeneic Mouse Model of Epithelial Ovarian Cancer Port Site Metastases

Epithelial ovarian cancer (EOC) is a deadly gynecologic malignancy, but animal models for the study of EOC pathophysiology and drug efficacy are limited. Based on the finding that women with EOC are at risk for metastasis at a trocar site after laparoscopy, we developed a syngeneic murine model of port-site metastasis of EOC. We leveraged the ID8 murine EOC cell line to induce intra-peritoneal tumors in mice. Once durable intraperitoneal tumor was confirmed with bioluminescence imaging, intra-abdominal wall tumors were induced by abdominal wall puncture with a hollow bore needle. This resulted in a robust system in which C57BL/6 mice developed metastatic deposits at a rate of 66.7% ± 10.77; no intra-abdominal wall metastases were seen in control samples (P = .0003, CI 41.16–90.84). Immunodeficient NOD SCID gamma mice developed puncture site metastases in 70% ± 10.0 of mice and also had no metastases documented in control sites (P = .002, CI 42.24–97.76). In addition we were able to demonstrate the presence of immune infiltrates within the metastatic deposits of C57BL/6 mice via IHC. Therefore, in this study we demonstrate the predictable development of invasive abdominal wall metastases in a syngeneic mouse model of EOC. This model enables studies of the metastatic process and provides a novel system in which to test the effect of therapies on a clinically-relevant model in an immune competent mouse.

Two-team management of vascular injuries concomitant with osteo-articular injuries in 36 patients over six years

BACKGROUND

Patients with both vascular and osteoarticular injuries require multidisciplinary management. Vascular injuries may be function- and/or life-threatening. The lower limbs are predominantly affected. Traffic, domestic, and work-related accidents contribute most of the cases. The primary objective of this study was to describe the management of patients with concomitant vascular and osteo-articular injuries, with special attention to the rates of amputation and fasciotomy. The secondary objective was to suggest a management sequence to optimise our surgical practice.

HYPOTHESIS

The management sequence is a crucial consideration in patients with both vascular and osteo-articular injuries.

MATERIAL AND METHODS

A 6-year, retrospective, observational study was conducted in patients with concomitant vascular and osteo-articular injuries.

RESULTS

The study included 36 patients with a mean age of 40.6±22.1 years. The main sources of injury were traffic accidents (n=19, 52.8%), crush injury (n=8, 22.2%), and falls (n=5, 13.9%). A compound fracture was present in 20 (55.6%) patients. Evidence of ischaemia in 25 (69.4%) patients, and bleeding in 11 (30.6%) patients. Pre-operative imaging, by ultrasonography or computed tomography, was performed in 27 (75.0%) patients. The lower limb was involved in 30 (83.3%) patients, who had osteoarticular injuries to the femur and leg combined with injury to the popliteal artery. Fasciotomy was performed in 11 (30.6%) patients and secondary amputation in 7 (19.4%) patients. The limb salvage rate was 80.6%. Median patient survival was 9.3 [0-74.8] months.

DISCUSSION

Coordinated work by two surgical teams is crucial to manage concomitant vascular and osteo-articular injuries. The management sequence must be defined clearly. Computed tomography angiography is the investigation of choice and should be performed at the slightest suspicion of vascular injury.

LEVEL OF EVIDENCE

IV, retrospective observational study.

[Posterior spinal cord neurostimulation in lumbar radiculitis pain. Apropos of 14 cases]

In 14 patients, spinal cord stimulation in lumbar radiculopathy follow multiple exploration or iterative surgery. For 10 out of this 14 patients treatment was successful; pain relief lasted a mean time of 12.7 months in 9 out of them.

Abstract 1534: Identification of LMX1B as a novel oncogene in human ovarian cancer

Ovarian cancers are thought to result from the accumulation of multiple genetic aberrations that transform ovarian and/or fallopian tube surface epithelial cells, allowing for their abnormal growth, proliferation and metastasis. We carried out genome-wide copy-number analysis using array comparative genomic hybridization on a panel of mouse ovarian cancer (OVCA) cell lines previously established in our laboratory. We identified a recurrent focal amplification on mouse chromosomal region 2qB, which contains the LIM homeodomain containing transcription factor 1B (Lmx1b) gene. LMX1B is not expressed in normal human ovary, but is expressed in many human OVCA cell lines and primary tumors. High expression of LMX1B correlates with poor outcome. To clarify the role of LMX1B in ovarian carcinogenesis, we transduced LMX1B into a panel of mouse and human OVCA cell lines and demonstrated that LMX1B strongly promotes migration of cancer cells in culture and accelerates xenograft growth in nude mice. Conversely, knockdown of LMX1B in a human cell line with endogenous high expression of LMX1B inhibits cell migration in vitro and tumor growth in vivo. Microarray analysis of cells overexpressing LMX1B identified NF-κB pathway as a potential mediator of tumor progression and subsequent treatment of NF-κB inhibitor decreased the migratory capacity of these cells. Thus, our data demonstrate that LMX1B functions as an oncogene in OVCA pathogenesis.

Citation Format: Gayatry Mohapatra, Lei He, Lankai Guo, Vinod Vathipadiekal, Petra Sergent, Whitfield Growdon, Bo Rueda, David Engler, Sandra Orsulic, Michael Birrer. Identification of LMX1B as a novel oncogene in human ovarian cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1534. doi:10.1158/1538-7445.AM2014-1534

Abstract 5093: Genome wide DNA copy number analysis of serous type ovarian carcinomas identifies genetic markers predictive of clinical outcome

Ovarian cancer is the fifth leading cause of cancer death in women. Ovarian cancers display a high degree of complex genetic alterations involving many oncogenes and tumor suppressor genes. Analysis of the association between genetic alterations and clinical endpoints such as survival will lead to improved patient management via genetic stratification of patients into clinically relevant subgroups. In this study, we aim to define subgroups of high-grade serous ovarian carcinomas that differ with respect to prognosis and overall survival. Genome-wide DNA copy number alterations (CNAs) were measured in 72 clinically annotated, high-grade serous tumors using high-resolution oligonucleotide arrays. Two clinically annotated, independent cohorts were used as validation sets. Unsupervised hierarchical clustering of copy number data resulted in two clusters with significant difference in progression free survival (PFS) and marginal difference in overall survival (OS). GISTIC analysis of the two clusters identified altered regions unique to each cluster. Supervised clustering of two independent large cohorts of high-grade serous tumors using the classification scheme derived from the two initial clusters validated our results and identified 8 genomic regions that are distinctly different among the subgroups. These 8 regions map to 8p21.3, 8p23.2, 12p12.1, 17p11.2, 17p12, 19q12, 20q11.21 and 20q13.12; and harbor potential oncogenes and tumor suppressor genes that are likely to be involved in the pathogenesis of ovarian carcinoma. We have identified a set of genetic alterations that could be used for stratification of high-grade serous tumors into clinically relevant treatment subgroups.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5093. doi:1538-7445.AM2012-5093

Immune checkpoint protein VISTA regulate autoimmunity and anti-tumor immunity (P2069)

V-domain Ig Suppressor of T cell Activation (VISTA) is a newly discovered immune checkpoint ligand that suppresses T cell activation. Our study demonstrates the critical role of VISTA in controlling autoimmunity and anti-tumor immunity. Within the hematopoietic compartment, VISTA is highly expressed on myeloid antigen-presenting cells, naïve T cells and Foxp3+ Tregs. Aged VISTA ko mice developed inflammatory phenotypes. When bred onto a TCR transgenic background that is specific for myelin oligodendrocyte glycoprotein (MOG), VISTA ko mice developed severe autoimmune disease at 6-7 weeks of age. VISTA also regulates the suppressive function of Foxp3+CD4+ regulatory T cells (Tregs), as well as the induction of adaptive Tregs in the periphery. During tumor development, VISTA expression is upregulated within the tumor microenvironment. A VISTA-specific monoclonal antibody (mab)-mediated blockade enhanced tumor-specific T cell priming, as well as altered the suppressive character of the tumor microenvironment by reducing tumor-infiltration of myeloid-derived suppressor cells while enhancing the infiltration and effector function of tumor-specific effector T cells. Consequently, VISTA mab-mediated blockade as a single reagent significantly suppressed the growth of both transplantable and inducible melanoma tumors, and when combined with a cancer vaccine, effectively eradicated established tumors. VISTA thus represents a novel and promising target for cancer immunotherapy.

Therapeutic role of the novel checkpoint regulator VISTA in murine autoimmune disease models. (P5174)

Negative checkpoint regulators are critical in triggering the immune response and in the clinic, therapeutics targeting the CTLA-4 and PD-L1 pathway have been successful in treating human cancers and marginal therapeutic efficacy noted in autoimmune diseases. Our lab recently identified a novel checkpoint regulator termed V-region Immunoglobulin-containing Suppressor of T cell Activation (VISTA). VISTA is structurally distinct from other members of the Ig superfamily. This study aimed to determine the therapeutic efficacy of VISTA in autoimmunity is effective. To address this, we investigated the role of a VISTA Ig fusion protein (VISTA-Ig) in autoimmune disease models of Multiple Sclerosis (Experimental Autoimmune Encephalomyelitis (EAE)) and Systemic Lupus Erythematosus (SLE). In sick EAE mice, therapeutic treatment with VISTA-Ig suppressed disease severity compared with untreated mice in vivo. In the lupus prone mouse strain NZBW-F1 which closely resembles human SLE, the prophylactic and therapeutic effect of VISTA-Ig was studied. Prophylactic treatment with VISTA-Ig prevented the onset of proteinuria and weight loss compared with untreated mice and therapeutic treatment reversed proteinuria in sick mice. Clinical evaluation of kidneys from the VISTA-Ig treated group showed minimal to mild glomerulonephritis compared with untreated mice. In conclusion we demonstrate that VISTA-Ig is a novel effective therapeutic in treating established autoimmune diseases.

An Abscopal Effect on Lung Metastases in Canine Mammary Cancer Patients Induced by Neoadjuvant Intratumoral Immunotherapy with Cowpea Mosaic Virus Nanoparticles and Anti-Canine PD-1

Neoadjuvant intratumoral (IT) therapy could amplify the weak responses to checkpoint blockade therapy observed in breast cancer (BC). In this study, we administered neoadjuvant IT anti-canine PD-1 therapy (IT acPD-1) alone or combined with IT cowpea mosaic virus therapy (IT CPMV/acPD-1) to companion dogs diagnosed with canine mammary cancer (CMC), a spontaneous tumor resembling human BC. CMC patients treated weekly with acPD-1 (n = 3) or CPMV/acPD-1 (n = 3) for four weeks or with CPMV/acPD-1 (n = 3 patients not candidates for surgery) for up to 11 weeks did not experience immune-related adverse events. We found that acPD-1 and CPMV/acPD-1 injections resulted in tumor control and a reduction in injected tumors in all patients and in noninjected tumors located in the ipsilateral and contralateral mammary chains of treated dogs. In two metastatic CMC patients, CPMV/acPD-1 treatments resulted in the control and reduction of established lung metastases. CPMV/acPD-1 treatments were associated with altered gene expression related to TLR1-4 signaling and complement pathways. These novel therapies could be effective for CMC patients. Owing to the extensive similarities between CMC and human BC, IT CPMV combined with approved anti-PD-1 therapies could be a novel and effective immunotherapy to treat local BC and suppress metastatic BC.