Neuroendocrine Immunophenotype as Predictor of Clinical Recurrence in 110 Patients with Prostate Cancer

We evaluated the relationship between NE expression and well-known prognostic factors and assessed whether tumor relapse after radical surgery correlates with the extent of NE differentiation. Radical prostatectomy specimens from 110 patients with clinically localized prostate cancer were assessed. Patients were followed up every three months for the first two years after surgery and six monthly for 5 additional years until failure, or for a mean of 48 months from the time of surgery for those who did not experience failure. The percentage of cells showing CgA immunoreactivity was evaluated using a visual quantitative method. Tumor staining was categorized as positive if >10% and negative if <10% of tumor cells were stained, to ensure that only cases with significant positivity were included in the positive group. The median follow-up was 5.4 years (range 1.8 to 7.2). The median time to clinical recurrence was 7.5 years and the median time to biochemical recurrence was 2.8 years. Of 31 patients (28%) who experienced a PSA recurrence, 15 developed a clinical recurrence. The mean preoperative PSA level was 9 ng/ml (range 2.7 to 25). Most cases were well differentiated (Gleason score <7), intraprostatic (≤pT2) tumors. Immunoreactivity in ≥10% of the cells was seen in 17.2% (n=19) of the tumor specimens. The preoperative PSA level, Gleason score, use of neoadjuvant or adjuvant therapy, lymphnode positivity were not statistically associated with NE expression. Only the primary pathologic stage appeared to be associated with CgA staining in the primary tumor (p=0.001). On the univariate analysis NE expression did not predict biochemical recurrence free survival, whereas it was associated with clinical recurrence. NE differentiation in clinically localized prostate cancer can be associated with failure after definitive surgical treatment, even if no conclusions can be drawn regarding its value as an independent prognostic factor.

CD28-mediated T cell response is upregulated by exogenous application of autologous Hsp70-peptide complex in a tumor-bearing host

Hsp70, a highly conserved protein, has gained plenty of attention by virtue of its adjuvant capability to induce peptide-specific cytotoxic T lymphocyte responses. In this study, we have investigated the effect of autologous Hsp70-peptide complex (or simply autologous Hsp70) on the expression of CD28 on T cells and its effector functions through macrophage activation. Further, we investigated the effect of Hsp70 on the expression of CD80 and CD86 on macrophages isolated from normal and tumor-bearing host to provide costimulatory signal for T cell activation and secretion of IL-2 and IFN-γ during interaction. We found that treatment of autologous Hsp70 effectively activated TAMs to induce higher expression of CD28 on T cells through T cells-macrophage interaction. Treatment of autologous Hsp70 induces higher expression of CD80 and CD86 on TAMs, as a result, increases B7/CD28 interaction, which in turns activates T cells and induces higher production of IL-2 and IFN-γ, thereby increasing antigen-specific T cell proliferation. With our novel study, we have provided the strong insights into the role of extracellular Hsp70 on the expression of CD28 costimulatory molecule on T cells, which helps in the activation and generation of antigen-specific T cell effector functions in a tumor-bearing host to curb malignancy.

Morphological effects of autologous hsp70 on peritoneal macrophages in a murine T cell lymphoma

Heat shock protein 70 is highly conserved cytosolic protein which have important role in growth, development, and apoptosis. Hsp70 is well-known activator of macrophages and enhances the release of specific and non-specific effector molecules that have major role in tumor destruction and immunopotentiation of host. However, morphological effects of hsp 70 has not been carried out, therefore, morphological effects of hsp 70 on murine peritoneal macrophages were examined by light microscopy and scanning electron microscopy. Thioglycolate-induced peritoneal macrophages were prepared from BALB/c mice and cultured for 24 h in the presence of the hsp70. Tumor-associated macrophages treated with 10 μg/ml were varied in shape, mostly spindle shaped, i.e., stretched bidirectionally; surface ruffles were increased and their lamellipodia was prominent which suggest that hsp 70 treatment not only enhances the functional state of the peritoneal macrophages but also initiate immense morphological changes leading to increased endothelium adherence, increased antigen uptake, and increased migration to the inflammatory site.

Anti-tumor immunity and mechanism of immunosuppression mediated by tumor cells: role of tumor-derived soluble factors and cytokines

The immune system plays a crucial role in the protection against tumor growth and progression. However, the activation of the immune system against the neoplastic cells does not always occur and, therefore, tumor cells are able to grow and progress continually in the host. It has now been realized that tumor cells themselves produce many of the important factors that are responsible for dismounting of effective immune response. These tumor-derived soluble factors invariably subdue the functions of almost every immune cell population. Therefore, we attempted to underline the mechanism of anti-tumor immune response and immunosuppression induced by tumor cells.