Adrian J. Correa

Epithelial Cell Adhesion Molecule (KSA) Expression Pathobiology and Its Role as an Independent Predictor of Survival in Renal Cell Carcinoma

Purpose: Epithelial cell adhesion molecule (EpCAM) is a widely expressed adhesion molecule in epithelial cancers. The purpose of this study is to determine the protein expression patterns of EpCAM in renal cell carcinoma (RCC) using tissue arrays linked to a clinicopathological database to evaluate both its predictive power in patient stratification and its suitability as a potential target for immunotherapeutic treatment strategies. Experimental Design: The University of California, Los Angeles kidney cancer tissue microarray contains specimens from 417 patients treated with nephrectomy. EpCAM protein expression in tumors and matched morphologically normal renal tissues was evaluated using anti-EpCAM immunohistochemistry. The resultant expression reactivity was correlated with clinicopathological variables. Results: EpCAM is consistently expressed in the distal nephron on normal renal epithelium. Clear cell RCCs show minimal and infrequent EpCAM expression, whereas chromophobe and collecting duct RCCs both demonstrate intense and frequent expression. Of 318 clear cell carcinomas used in the analysis, 10% were EpCAM positive in ≥50% of cells, and 8% of patients would be considered candidates for EpCAM-based therapy, based on high expression [≥moderate intensity and frequent (≥50%) expression] and the need for systemic treatment. EpCAM expression was an independent prognostic factor for improved disease-specific survival, with a multivariate hazard ratio of 0.63 (P = 0.017; 95% confidence interval, 0.43–0.92). Conclusions: EpCAM is a novel prognostic molecular marker in RCC patients, and its positive expression is an independent predictor associated with improved survival. However, high expression in morphologically normal renal tissues and minimal or absent expression in clear cell carcinomas will likely limit the utility of this epithelial marker in targeted treatments of this most common RCC type.

Establishment and Characterization of a Novel Head and Neck Squamous Cell Carcinoma Cell Line USC-HN1

BackgroundHead and neck squamous cell carcinoma (HNSCC) is an aggressive and lethal malignancy. Publically available cell lines are mostly of lingual origin, or have not been carefully characterized. Detailed characterization of novel HNSCC cell lines is needed in order to provide researchers a concrete keystone on which to build their investigations.MethodsThe USC-HN1 cell line was established from a primary maxillary HNSCC biopsy explant in tissue culture. The immortalized cells were then further characterized by heterotransplantation in Nude mice; immunohistochemical staining for relevant HNSCC biomarkers; flow cytometry for surface markers; cytogenetic karyotypic analysis; human papillomavirus and Epstein-Barr virus screening; qRT-PCR for oncogene and cytokine analysis; investigation of activated, cleaved Notch1 levels; and detailed 35,000 gene microarray analysis.ResultsCharacterization experiments confirmed the human HNSCC origin of USC-HN1, including a phenotype similar to the original tumor. Viral screening revealed no HPV or EBV infection, while western blotting displayed significant upregulation of activated, cleaved Notch1.ConclusionsUSC-HN1, a novel immortalized cell line has been derived from a maxillary HNSCC. Characterization studies have shown that the cell line is of HNSCC origin and displays many of the same markers previously reported in the literature. USC-HN1 is available for public research and will further the investigation of HNSCC and the development of new therapeutic modalities.

BRAFV600E in Papillary Thyroid Carcinoma Is Associated with Increased Programmed Death Ligand 1 Expression and Suppressive Immune Cell Infiltration

BACKGROUND There remain a small number of patients with papillary thyroid cancer (PTC) who suffer recurrence, metastases, or death. While mutation of the BRAF gene, corresponding to the constitutively active BRAF(V600E) protein, has been associated with worse clinical outcomes in thyroid cancer, the reasons underlying this observation are presently unknown. Disruption of endogenous host immune surveillance and promotion of tumor immune escape is one mechanism by which BRAF(V600E) tumors may achieve more aggressive behavior. This study evaluated the relationship between BRAF(V600E) status and known strategies of tumor-mediated immune suppression. METHODS Tissue sections of PTC tumors from 33 patients were evaluated by immunohistochemistry for tumor-expressed suppressive ligands and enzymes and effector and suppressor populations of tumor-infiltrating immune cells. Presence of BRAF(V600E) was evaluated by direct DNA sequencing of PTC specimens and the results correlated with tumor-expressed molecules and tumor-infiltrating immune cell populations, as well as patient characteristics and pathologic findings. RESULTS BRAF(V600E) tumors more often express high levels of immunosuppressive ligands programmed death ligand 1 (53% vs. 12.5%) and human leukocyte antigen G (41% vs. 12.5%) compared to BRAF wild-type tumors. There was no association between indoleamine 2,3-dioxygenase 1 expression and BRAF(V600E) status. Furthermore, BRAF(V600E) tumors demonstrate both lower CD8(+) effector to FoxP3(+) regulatory T cell, and CD68(+) pan-macrophage to CD163(+) M2 macrophage ratios, indicating relative increases in suppressive T cell and macrophage components, respectively. CONCLUSIONS Overall, BRAF(V600E) PTC tumors display a broadly immunosuppressive profile and evidence of disturbed host tumor immune surveillance that may contribute to the poorer outcomes observed in this subset of patients with thyroid cancer.

Immunohistochemical panel to differentiate endometrial stromal sarcoma, uterine leiomyosarcoma and leiomyoma: something old and something new

Aims To evaluate an immunohistochemical panel differentiating endometrial stromal sarcoma (ESS) from uterine leiomyosarcoma (ULMS) and leiomyoma (LM). Methods 94 cases (28 ESS, 41 ULMS, 25 LM) were retrieved and arrayed. 10 immunomarkers (estrogen receptor (ER), progesterone receptor (PR), CD10, smooth muscle actin, desmin, h-caldesmon, transgelin, GEM, ASC1, stathmin1) were used. A predictive model was constructed and examined by receiver operating characteristics curve analysis to determine area under the curve (AUC). Results The combination of ER+/PR+/CD10+/GEM−/h-caldesmon−/transgelin− can predict ESS versus ULMS with AUC predictive value of 0.872 (95% CI 0.784 to 0.961, p<0.0001). The combination of ER+/PR+/CD10+/h-caldesmon−/transgelin− can predict low grade (LG) ESS from ‘LG’ ULMS with AUC predictive value of 0.914 (95% CI 0.832 to 0.995, p<0.0001). Finally, ULMS and ESS, including the LGs, were more likely to be stathmin1+ than LM. Conclusions Due to the different clinical course and management, adding novel antibodies (GEM, transgelin) to the well established immunohistochemistry panel seemed to be useful in distinguishing ESS from ULMS and LG ESS from ‘LG’ ULMS. Finally, stathmin1 expression could be of value in differentiating LM from uterine sarcomas.

USC-HN2, a new model cell line for recurrent oral cavity squamous cell carcinoma with immunosuppressive characteristics

Head and neck squamous cell carcinomas (HNSCC) are common and aggressive tumors that have not seen an improvement in survival rates in decades. These tumors are believed to evade the immune system through a variety of mechanisms and are therefore highly immune modulatory. In order to elucidate their interaction with the immune system and develop new therapies targeting immune escape, new pre-clinical models are needed. A novel human cell line, USC-HN2, was established from a patient biopsy specimen of invasive, recurrent buccal HNSCC and characterized by morphology, heterotransplantation, cytogenetics, phenotype, gene expression, and immune modulation studies and compared to a similar HNSCC cell line; SCCL-MT1. Characterization studies confirmed the HNSCC origin of USC-HN2 and demonstrated a phenotype similar to the original tumor and typical of aggressive oral cavity HNSCC (EGFR(+)CD44v6(+)FABP5(+)Keratin(+) and HPV(-)). Gene and protein expression studies revealed USC-HN2 to have highly immune-modulatory cytokine production (IL-1β, IL-6, IL-8, GM-CSF, and VEGF) and strong regulatory T and myeloid derived suppressor cell (MDSC) induction capacity in vitro. Of note, both USC-HN2 and SCCL-MT1 were found to have a more robust cytokine profile and MDSC induction capacity when compared to seven previously established HNSCC cell lines. Additionally, microarray gene expression profiling of both cell lines demonstrate up-regulation of antigen presenting genes. Because USC-HN2 is therefore highly immunogenic, it also induces strong immune suppression to evade immunologic destruction. Based upon these results, both cell lines provide an excellent model for the development of new suppressor cell-targeted immunotherapies.

Diagnostic accuracy of integrated intravascular ultrasound and optical coherence tomography (IVUS-OCT) system for coronary plaque characterization

Intravascular ultrasound (IVUS) imaging and optical coherence tomography (OCT), two commonly used intracoronary imaging modalities, play important roles in plaque evaluation. The combined use of IVUS (to visualize the entire plaque volume) and OCT (to quantify the thickness of the plaque cap, if any) is hypothesized to increase plaque diagnostic accuracy. Our group has developed a fully-integrated dual-modality IVUS-OCT imaging system and 3.6F catheter for simultaneous IVUS-OCT imaging with a high resolution and deep penetration depth. However, the diagnostic accuracy of an integrated IVUS-OCT system has not been investigated. In this study, we imaged 175 coronary artery sites (241 regions of interest) from 20 cadavers using our previous reported integrated IVUS-OCT system. IVUS-OCT images were read by two skilled interventional cardiologists. Each region of interest was classified as either calcification, lipid pool or fibrosis. Comparing the diagnosis by cardiologists using IVUSOCT images with the diagnosis by the pathologist, we calculated the sensitivity and specificity for characterization of calcification, lipid pool or fibrosis with this integrated system. In vitro imaging of cadaver coronary specimens demonstrated the complementary nature of these two modalities for plaques classification. A higher accuracy was shown than using a single modality alone.

Botulinum toxin to improve vessel graft patency in cerebral revascularization surgery: report of 3 cases

Surgical revascularization continues to play an important role in the management of complex intracranial aneurysms and ischemic cerebrovascular disease. Graft spasm is a common complication of bypass procedures and can result in ischemia or graft thrombosis. The authors here report on the first clinical use of botulinum toxin to prevent graft spasm following extracranial-intracranial (EC-IC) bypass. This technique was used in 3 EC-IC bypass surgeries, 2 for symptomatic carotid artery occlusions and 1 for a ruptured basilar tip aneurysm. In all 3 cases, the harvested graft was treated ex vivo with botulinum toxin before the anastomosis was performed. Post-bypass vascular imaging demonstrated patency and the absence of spasm in all grafts. Histopathological analyses of treated vessels did not show any immediate endothelial or vessel wall damage. Postoperative angiograms were without graft spasm in all cases. Botulinum toxin may be a reasonable option for preventing graft spasm and maintaining patency in cerebral revascularization procedures.

Churg-Strauss Syndrome Presenting As Acute Necrotizing Eosinophilic Myocarditis. Concise review of the literature.

BACKGROUND Acute eosinophilic myocarditis (EM) is a rare form of heart failure that is characterized by myocardial eosinophilic infiltration usually in association with peripheral eosinophilia. The underlying cause is variable and can include allergic reactions, parasitic infection, idiopathic hypereosinophilic syndrome, malignancy, Loefflers syndrome, Churg-Strauss syndrome (CSS), early giant cell myocarditis and malignancy. The course is potentially fatal, and early diagnosis and treatment with steroids is essential. CONCLUSION Here, we present an illustrative case of eosinophilic myocarditis secondary to CSS followed by a brief review of epidemiology, pathogenesis, diagnosis and treatment of both disease entities.

Near Complete Necrosis of a Giant Cell Tumor After Treatment with Denosumab

Giant cell tumor of bone is an uncommon locally aggressive neoplasm accounting for 10% to 15% of all benign bone tumors1-3. The standard treatment has been surgical, with extended intralesional curettage utilizing either chemical or thermal adjuvants for tumors contained within the bone1-8. Tumors extending beyond the cortex with an associated soft-tissue mass are typically treated with wide resection1-9. If the tumor is near a joint, the reconstruction often involves an allograft or endoprosthetic replacement, which can lead to substantial disability and limitations in quality of life9,10. When located in the pelvis or spine, giant cell tumors can often be inoperable, or resection can result in considerable morbidity11-14. The recurrence rate of giant cell tumors has been reported to range from 7.9% to 27% with intralesional resection, despite the use of surgical adjuvants5-8, and from 0% to 7% when wide resection is performed5-8. External beam radiation has had limited success in the treatment of these patients15-17, and chemotherapeutic options have thus far been few and unsuccessful18-20. In the last few years, the discovery that denosumab, a nuclear factor kappa-B ligand (RANKL) antibody, may have activity against giant cell activation has led to clinical trials of this drug for giant cell tumors of bone21-23. Thomas et al.24 reported a study of thirty-seven patients with recurrent or unresectable giant cell tumors who underwent treatment with denosumab, in which thirty of thirty-five patients (86%) had either histological improvement or improvement on imaging studies as a result of the RANKL inhibition. We report the case of a patient with a large giant cell …

Abstract 3531: Papillary thyroid carcinomas with and without lymph node metastasis show differences in tumor-infiltrating leukocytes

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Papillary thyroid carcinoma is the most common endocrine malignancy with approximately 48,000 new cases expected in 2011. Additionally, the incidence has doubled over the last three decades. While 20-year survival rates are extremely high with usual therapy, 15% will have recurrence and 5-10% will die from their disease. If refractory to standard treatment, no sufficient adjuvant therapies are available. Cancer immunotherapy uses a patients own immune system to recognize and eliminate malignant cells. The potential advantages of this approach over conventional treatments include the systemic trafficking of immune cells to treat primary and metastatic disease, inherent antigen-specificity of adaptive immunity to minimize collateral damage, and most importantly, the induction of immunological memory to prevent recurrent disease. The degree and type of immune response are poorly understood in thyroid cancer. In this study, papillary thyroid cancer samples, with normal tissue matched to the same specimen, from de-identified patients were obtained retrospectively from the Norris Cancer Center Tumor Bank and stained using immunohistochemistry with antibodies specific for CD8 and CD16. Sections were evaluated for tumor-infiltrating leukocyte location, intra-tumor versus invading margin, and percentage of CD8 or CD16 positive lymphocytes, respectively. The results were analyzed for correlation between immune infiltrate and clinical parameters. Nineteen cases of papillary thyroid cancer were studied. The mean patient age was 40 years (range 22-55). Seven of nineteen patients had lymph node metastasis. An organized lymphocytic infiltration was seen in seven samples and was significantly correlated with the presence with CD8+ and CD16+ cells, at the invading margin and tumor parenchyma, respectively. Age <40 years was significantly associated with this pattern of CD8+ and CD16+ cells compared to those older than 40. Lymph node metastasis was significantly association with an increased level of intra-tumoral CD8+ cell infiltration and there was a non-significant trend towards a positive association between nodal metastasis and intra-tumoral CD16+ cell infiltration. The present study demonstrates an increase in cell-mediated immune infiltration in samples that have nodal metastases versus those that do not, suggesting that immune therapy may be utilized in the future treatment of aggressive thyroid carcinoma to improve disease response. 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 3531. doi:1538-7445.AM2012-3531