Up-regulation of proliferative and migratory genes in regulatory T cells from patients with metastatic castration-resistant prostate cancer.

A higher frequency of regulatory T cells (Tregs) has been observed in peripheral blood mononuclear cells (PBMC) of patients with different types of solid tumors and hematological malignancies as compared to healthy donors. In prostate cancer patients, Tregs in PBMC have been shown to have increased suppressive function. Tumor-induced biological changes in Tregs may enable tumor cells to escape immunosurveillance. We performed genome-wide expression analyses comparing the expression levels of more than 38,500 genes in Tregs with similar suppressive activity, isolated from the peripheral blood of healthy donors and patients with metastatic castration-resistant prostate cancer (mCRPC). The differentially expressed genes in mCRPC Tregs are involved in cell cycle processes, cellular growth and proliferation, immune responses, hematological system development and function and the interleukin-2 (IL-2) and transforming growth factor-ß (TGF-ß) pathways. Studies revealed that the levels of expression of genes responsible for T-cell proliferation (C-FOS, C-JUN and DUSP1) and cellular migration (RGS1) were greater in Tregs from mCRPC patients as compared to values observed in healthy donors. Increased RGS1 expression in Tregs from mCRPC patients suggests a decrease in these Tregs' migratory ability. In addition, the higher frequency of CD4(+) CD25(high) CD127(-) Tregs in the peripheral blood of mCRPC patients may be the result of an increase in Treg proliferation capacity. Results also suggest that the alterations observed in gene expression profiles of Tregs in mCRPC patients may be part of the mechanism of tumor escape from host immune surveillance.

Maturation of human dendritic cells with Saccharomyces cerevisiae (yeast) reduces the number and function of regulatory T cells and enhances the ratio of antigen-specific effectors to regulatory T cells.

We compared the effects of yeast-treated human dendritic cells (DCs) with CD40L-matured human DCs for the induction of effector cells and the number and functionality of CD4(+)CD25(+)CD127(-)FoxP3(+) regulatory T cells (Tregs). DCs were treated with yeast or CD40L and cocultured with isolated autologous CD4(+) T cells. CD4(+)CD25(+)CD127(-) T cells isolated from the coculture of CD4(+) T cells plus yeast-treated DCs (yeast coculture) had a lower expression of FoxP3 and decreased suppressive function compared to CD4(+)CD25(+)CD127(-) T cells isolated from the coculture of CD4(+) T cells plus CD40L-treated DCs (CD40L coculture). Also, compared to the CD40L coculture, the yeast coculture showed increases in the ratio of CD4(+)CD25(+) activated T cells to Tregs and in the production of Th1-related cytokines (IL-2, TNF-α, IFN-γ) and IL-6. In addition, yeast-treated DCs used as antigen-presenting cells (APCs) incubated with the tumor antigen CEA enhanced the proliferation of CEA-specific CD4(+) T cells compared to the use of CD40L-matured DCs used as APCs. This is the first study to report on the role of yeast-treated/matured human DCs in reducing Treg frequency and functionality and in enhancing effector to Treg ratios. These results provide an additional rationale for the use of yeast as a vector in cancer vaccines.

Strategies for cancer vaccine development.

Treating cancer with vaccines has been a challenging field of investigation since the 1950s. Over the years, the lack of effective active immunotherapies has led to the development of numerous novel strategies. However, the use of therapeutic cancer vaccines may be on the verge of becoming an effective modality. Recent phase II/III clinical trials have achieved hopeful results in terms of overall survival. Yet despite these encouraging successes, in general, very little is known about the basic immunological mechanisms involved in vaccine immunotherapy. Gaining a better understanding of the mechanisms that govern the specific immune responses (i.e., cytotoxic T lymphocytes, CD4 T helper cells, T regulatory cells, cells of innate immunity, tumor escape mechanisms) elicited by each of the various vaccine platforms should be a concern of cancer vaccine clinical trials, along with clinical benefits. This review focuses on current strategies employed by recent clinical trials of therapeutic cancer vaccines and analyzes them both clinically and immunologically.

Gemcitabine plus metronomic 5-fluorouracil or capecitabine as a second-/third-line chemotherapy in advanced adrenocortical carcinoma: a multicenter phase II study.

Adrenocortical carcinoma (ACC) is a rare neoplasm characterized by poor prognosis. First-line systemic treatments in advanced disease include mitotane, either alone or in combination with chemotherapy. Studies evaluating second-line therapy options have obtained disappointing results. This trial assessed the activity and toxicity of gemcitabine plus metronomic fluoropyrimidines in heavily pretreated advanced ACC patients. From 1998 to 2008, 28 patients with advanced ACC progressing after mitotane plus one or two systemic chemotherapy lines were enrolled. They received a combination of i.v. gemcitabine (800 mg/m(2), on days 1 and 8, every 21 days) and i.v. 5-fluorouracil protracted infusion (200 mg/m(2)/daily without interruption until progression) in the first six patients, or oral capecitabine (1500 mg/daily) in the subsequent patients. Mitotane administration was maintained in all cases. The rate of non-progressing patients after 4 months of treatment was 46.3%. A complete response was observed in 1 patient (3.5%); 1 patient (3.5%) obtained a partial regression, 11 patients (39.3%) obtained a disease stabilization and 15 patients (53.7%) progressed. Treatment was well tolerated, with grade III and IV toxicities consisting of leukopenia in six patients (21.4%), thrombocytopenia in one patient (3.5%), and mucositis in one patient (3.5%). Median time to progression and overall survival in the patient population were 5.3 (range: 1-43) and 9.8 months (range: 3-73) respectively. Gemcitabine plus metronomic fluoropyrimidines is a well-tolerated and moderately active regimen in heavily pretreated ACC patients.

BRCA1 genetic testing in 106 breast and ovarian cancer families from Southern Italy (Sicily): a mutation analyses.

PURPOSE: To evaluate the contribution of germline BRCA1 mutations in the incidence of hereditary and familial Breast Cancer (BC) and/or Ovarian Cancer (OC) in patients from Southern Italy (in the region of Sicily) and to identify a possible association between the higher frequency of BRCA1 mutations and a specific familial profile. EXPERIMENTAL DESIGN: A consecutive series of 650 patients with BC and/or OC diagnosed between 1999 and 2005 were recruited from the Southern Italian region of Sicily, after interview at the "Regional Reference Centre for the Characterization and Genetic Screening of Hereditary Tumors" at the University of Palermo. Genetic counselling allowed us to recruit a total of 106 unrelated families affected with breast and/or ovarian cancer screened for mutations occurring in the whole BRCA1 gene by automatic direct sequencing. RESULTS: Germline BRCA1 mutations were found in 17 of 106 (16%) Sicilian families. The HBOC profile had a major frequency (66%) of mutations (P < 0.01). A total of 28 sequence variants was identified. Seven of these were pathogenic, 5 unknown biological variant (UV) and 16 polymorphisms. We also identified a pathological mutation (4843delC) as a possible Sicilian founder mutation. CONCLUSIONS: The present study is the first BRCA1 disease-associated mutations analysis in Southern Italian families. The early age of onset of such tumors and the association with the HBOC familial profile could be two valid screening factors for the identification of BRCA1 mutation carriers. Finally, we identified a BRCA1 mutation with a possible founder effect.

FOLFOX-4 stop and go and capecitabine maintenance chemotherapy in the treatment of metastatic colorectal cancer.

OBJECTIVE: Patients with metastatic colorectal cancer (MCC) usually receive FOLFOX-4, or other oxaliplatin (L-HOP)-based regimens, until the occurrence of progressive disease, with an increase in the incidence of neurotoxicity which is correlated to the cumulative dose of L-HOP. The aim of this study was to evaluate if FOLFOX-4 stop and go and capecitabine maintenance chemotherapy is associated with a low incidence of severe neurotoxicity in the treatment of MCC patients. METHODS: Thirty-three patients were treated with FOLFOX-4 (L-HOP 85 mg/m(2) day 1, leucovorin 200 mg/m(2), 5-fluorouracil bolus 400 mg/m(2) and 22 h 600 mg/m(2) days 1 and 2, every 2 weeks). Patients who achieved objective response (OR) or stable disease (SD) then received oral capecitabine 2,500 mg/m(2) days 1-14 every 3 weeks; L-HOP was reintroduced as soon as progression occurred. RESULTS: Twenty-eight of the 29 patients who achieved OR or SD then received capecitabine. FOLFOX-4 was reintroduced in 18 patients (56.2%). The median response duration (RD) was 9.2 months and median progression-free survival (PFS) was 8.6 months. Twenty-eight patients (87.5%) had peripheral neuropathy during treatment, but grade 3 neurotoxicity was observed in only 1 patient (3.1%). CONCLUSIONS: FOLFOX-4 stop and go and capecitabine maintenance chemotherapy was associated with a very low incidence of grade 3 neurotoxicity. Although the number of patients enrolled was far too low for a definite conclusion, RD and PFS were comparable to those usually reported in the treatment of MCC patients.

Chemo-immunotherapy of metastatic colorectal carcinoma with gemcitabine plus FOLFOX 4 followed by subcutaneous granulocyte macrophage colony-stimulating factor and interleukin-2 induces strong immunologic and antitumor activity in metastatic colon cancer patients.

PURPOSE: Tumor cell killing by anticancer drugs may be supported by their immuno- and pharmacologic effects. Chemotherapy is in fact able to (A) upregulate tumor-associated antigen expression, including carcinoembryonic antigen (CEA) or other target molecules such as thymidylate synthase (TS); and (B) downregulate tumor cell resistance to the death signals induced by tumor antigen-specific cytotoxic T lymphocytes. This provides the rationale for combining chemo- and immunotherapy. MATERIALS AND METHODS: We describe the results of a translational phase II trial designed to evaluate the toxicity, antitumor activity and immunologic effects of gemcitabine + FOLFOX-4 (oxaliplatin, fluorouracil, and folinic acid) polychemotherapy followed by the subcutaneous administration of granulocyte macrophage colony-stimulating factor and low-dose interleukin-2 in colorectal carcinoma patients. The study involved 29 patients (16 males and 13 females with a mean age of 69 years), 21 of whom had received a previous line of treatment, and 19 had liver involvement. RESULTS: The treatment was well tolerated and induced very high objective response (68.9%) and disease control rates (96.5%), with an average time to progression of 12.5 months. An immunologic study of peripheral blood mononuclear cells (PBMCs) taken from 20 patients showed an enhanced proliferative response to colon carcinoma antigen and a significant reduction in suppressive regulatory T lymphocytes (CD4+CD25T-reg+). A cytofluorimetric study of the PBMCs of five HLA-A(*)02.01+ patients who achieved an objective response showed an increased frequency of cytolytic T lymphocyte precursors specific for known CEA- and TS-derived epitopes. CONCLUSION: The results show that our regimen has strong immunologic and antitumor activity in colorectal cancer patients and deserves to be investigated in phase III trials.

Gemcitabine (GEM) plus oxaliplatin, folinic acid, and 5-fluorouracil (FOLFOX-4) in patients with advanced gastric cancer.

BACKGROUND AND AIMS: oxaliplatin in combination with folinic acid (FA) and infusional 5-fluorouracil (5-FU) has shown significant anti-tumor activity in gastric cancer patients (FOLFOX). Previous studies have shown that gemcitabine (GEM), a new fluorinated anti-metabolite, enhances the individual anti-tumor activity of either 5-FU or oxaliplatin. We have therefore designed a multi-center phase II trial in order to test a novel GEM+FOLFOX-4 regimen in patients with metastatic gastric cancer. METHODS: we enrolled 36 patients, 28 males and 8 females, with an average age of 64.4 years (range 37-78), who received bi-weekly treatment with GEM (1,000 mg/m2 on day 1), levo-FA (100 mg/m2 on days 1 and 2), a 5-FU (400 mg/m2) bolus injection followed by 22-h continuous infusion (800 mg/m2) on days 1 and 2, and oxaliplatin 85 mg/m2 in a 4-6 h intravenous (i.v.) infusion before the second FUFA administration on day 2. RESULTS: the most frequent side effect was grade 1-2 hematological toxicity and late sensorial neurotoxicity. Two patients developed hypersensitivity to oxaliplatin while another developed an aseptic eosinophilic pneumonitis. Two patients refused to continue the treatment after two cycles of chemotherapy and were lost at the follow-up. Among the remaining 34 patients four achieved a complete response, 15 a partial response, 12 had a stable disease and three progressed. CONCLUSIONS: these results may grant the rationale to evaluate this multi-drug combination in randomized phase III trials in advanced gastric cancer.