María Guadalupe Pallotta

Plasma metalloproteinase activity is enhanced in the euglobulin fraction of breast and lung cancer patients

Matrix metalloproteinases (MMP) have been implicated in tumor invasion and metastasis. We verified, by gelatin zymography, MMP activity in the euglobulin plasma fraction of 82 healthy controls, 66 patients with benign diseases and 149 patients with breast, lung, colon or brain cancer. The euglobulin fractions assayed showed 4 gelatinolytic bands of 62, 92, 120 and 200 kDa. The median (Md) value for 92 kDa‐MMP activity was significantly increased in breast (Md 1.34 arbitrary units [AU]/ml plasma, range 0.0–7.2) and lung cancer patients (Md 1.43 AU/ml, range 0.0–3.6) compared with the controls (Md 0.48 AU/ml, range 0.0–1.8). Patients with colon cancer or gliomas presented values of MMP‐9 similar to those of the healthy population. Multivariate analysis indicated that plasma MMP‐9 activity was not predicted by the known clinicopathological parameters such as age, stage, tumor size, number of positive lymph nodes, histologic grade, histologic type, nuclear grade or mitotic index. Lung cancer patients also presented high values of MMP‐9 (Md 1.43, range 0.0–3.6 [n = 26]), without association with tumor stage or histologic type. The levels of 92 kDa‐MMP activity in the plasma euglobulin fraction could be a potentially useful tumor marker in breast and lung cancer. Int. J. Cancer 89:389–394, 2000.

PKC delta (PKCδ) promotes tumoral progression of human ductal pancreatic cancer

Objective: Our objective was to study the role of protein kinase C delta (PKC&dgr;) in the progression of human pancreatic carcinoma. Methods: Protein kinase C delta expression in human ductal carcinoma (n = 22) was studied by immunohistochemistry. We analyzed the effect of PKC&dgr; overexpression on in vivo and in vitro properties of human ductal carcinoma cell line PANC1. Results: Human ductal carcinomas showed PKC&dgr; overexpression compared with normal counterparts. In addition, in vitro PKC&dgr;-PANC1 cells showed increased anchorage-independent growth and higher resistance to serum starvation and to treatment with cytotoxic drugs. Using pharmacological inhibitors, we determined that phosphatidylinositol-3-kinase and extracellular receptor kinase pathways were involved in the proliferation of PKC&dgr;-PANC1. Interestingly, PKC&dgr;-PANC1 cells showed a less in vitro invasive ability and an impairment in their ability to migrate and to secrete the proteolytic enzyme matrix metalloproteinase-2. In vivo experiments indicated that PKC&dgr;-PANC1 cells were more tumorigenic, as they developed tumors with a significantly lower latency and a higher growth rate with respect to the tumors generated with control cells. Besides, only PKC&dgr;-PANC1 cells developed lung metastasis. Conclusion: Our results showed that the overexpression of PKC&dgr; in PANC1 cells induced a more malignant phenotype in vivo, probably through the modulation of cell proliferation and survival, involving phosphatidylinositol-3-kinase and extracellular receptor kinase signaling pathways.

Neural cell adhesion molecule in human serum. Increased levels in dementia of the Alzheimer type

Memory impairment is a process associated with alterations in neuronal plasticity, synapses formation, and stabilization. As the neural cell adhesion molecule (NCAM) plays a key role in synaptic bond stabilization, we analyzed the usefulness of soluble NCAM isoforms in the diagnosis of patients with dementia of the Alzheimer type (DAT). NCAM was measured in the sera of 70 control subjects and 43 DAT patients (with different severity of cognitive impairment, GDS), employing Western blot and densitometric quantification. LMW-NCAM bands (100-130 kDa) decreased significantly with age independently of sex. DAT patients presented values of LMW-NCAM and HMW-NCAM significantly higher than healthy controls of similar age (higher than 130 kDa). Only LMW-NCAM was associated with GDS. Our results suggest that NCAM could be involved in the pathogenesis of DAT disorder and that serum NCAM levels could be useful as differential diagnostic markers of the disease.

Prognostic value of Mdm2, p53 and p16 in patients with astrocytomas.

Surgical cure of gliomas infiltrating into the brain is practically impossible and their clinical course is primarily determined by the biological behavior of the tumor cell. The purpose of this study was to analyze retrospectively prognostic input of p53, Mouse double minute-2 (Mdm2) and p16 in 103 uniformly treated patients with astrocytic tumors. The expression of these molecules was measured by immunohistochemical procedure. Prognostic evaluation was performed with the multivariate proportional hazards model. The follow-up period lasted 19 (5–122) months for the survivors. We observed that 66% of gliomas showed mutated p53, while only 17% overexpressed Mdm2, the p53-regulatory molecule. Besides, almost 50% of gliomas lost p16 immunopositivity. Only p53 labeling showed a positive correlation with the grade of malignancy, according with the WHO classification. The association between mutated p53 and histological grade remained when prognostic variables were considered in a multivariate analysis. No association between p53 status and overall survival was found. On the other hand, Mdm2 overexpression and, unexpectedly, p16 immunopositivity were associated with a shorter survival in an univariate analysis. However, Cox-regression analysis showed that only Mdm2 in female patients was an independent prognostic factor, associated with shorter survival.In conclusion, our results suggest that Mdm2 could be a relevant marker in determining the evolution of glioma patients and could provide a more objective way to classify astrocytomas.

Association between mast cells of different phenotypes and angiogenesis in colorectal cancer

It is known that mast cells proliferate in solid tumours and increase tumour angiogenesis. Nevertheless, there is no consensus regarding their role in colorectal cancer (CRC). In this study, we aimed to clarify the relationship of mast cells positive for tryptase (MCts) and tryptase-chymase (MCtcs) with microvessel density (MVD) in the intratumoral zone and the invasive edge of 80 CRC patient tumours. We evaluated these parameters and associated their expression with clinicopathological parameters, including survival rate. Tumour sections from each patient were immunostained for tryptase to evaluate MCts, chymase to evaluate MCtcs, and CD34 to evaluate microvessel counts under x100 microscopy. The number of MCs of both phenotypes and the MVD counts were higher in the invasive edge than in the intratumoral zone (p<0.001). MCt numbers were higher than those of MCtcs in all Astler-Coller stages in both regions. A positive correlation between MVD and MCts or MCtcs was observed (Pearsons test p<0.001). Neither the number of MCs nor MVD was associated with overall survival (log rank test). However, only 8.3% of patients with low numbers of MCtcs in the invasive edge succumbed to the disease, compared to 32% with high numbers of MCtcs. Our results indicate that angiogenesis and MC hyperplasia are events which appear early during CRC development. The correlation of MC phenotypes with MVD is in agreement with the role attributed to MCs, that of angiogenesis enhancement. Collectively, these findings suggest that screening during the early malignization of CRC can provide valuable clinical information.

Abstract 12: Serum carbonic anhydrase IX (CAIX) as diagnostic biomarker in clear cell renal cell carcinoma (ccRCC) patients .

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Clinicians face important pitfalls in the treatment of Renal cell carcinoma (RCC), such as absence of symptoms in early stages of the disease, its high metastatic potential and its resistance to conventional therapy. These facts emphasize the requirement of early diagnosis to optimize the chance of cure. ccRCC, the most common histological type of RCC, is considered a cell metabolic disease which develops from the activation of pseudohypoxic pathways. The transmembrane enzyme CAIX, involved in pH homeostasis and expressed in ccRCC tumors, is considered to be one of the best cellular biomarkers of hypoxia. Our aim was to study the role of serum CAIX as diagnostic biomarker of ccRCC, taking into account that serum contains a rich untapped source of disease-specific information. Employing a quantitative ELISA test (RD MW test p<0.001). Then, we analyzed whether already established clinicopathological variables in RCC were associated with serum CAIX levels, finding a remarkable correlation with tumor size (Spearman test p<0.01). Then, we investigated the usefulness of serum CAIX in the follow-up of these patients. Interestingly in 20/30 (66.7%) ccRCC patients values of CAIX decreased after tumor removal (S2 vs S1). We conclude that serum CAIX could be a useful diagnostic biomarker in ccRCC patients. This would be of relevant importance as there is a lack of molecular biomarkers for this pathology. Citation Format: Maria Elena Knott, Myriam Nunez, Maria Natalia Gandur Quiroga, Gaston Boggio, Julieta Grasselli, Guillermo Gueglio, Pedro Rondot Radio, Mariano Brzesinski, Leonardo Pasik, Carla Pulero, Ana Alvarez, Hector Malagrino, Patricio Garcia Marchinena, Alberto Jurado, Elisa Bal de Kier Joffe, Maria Guadalupe Pallotta, Lydia I. Puricelli. Serum carbonic anhydrase IX (CAIX) as diagnostic biomarker in clear cell renal cell carcinoma (ccRCC) patients . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 12. doi:10.1158/1538-7445.AM2013-12