Pierpaolo Correale

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.

Regulatory (foxp3+) T-cell Tumor Infiltration Is a Favorable Prognostic Factor in Advanced Colon Cancer Patients Undergoing Chemo or Chemoimmunotherapy

Antitumor immune response and chemotherapy-induced immunomodulation in colon cancer patients represented the rationale to design new strategies, like GOLFIG chemoimmunotherapy (gemcitabine, oxaliplatin, 5-fluorouracil/folinic acid, granulocyte macrophage colony-stimulating factor, and aldesleukine), that resulted a safe and very active regimen. Antitumor activity and immunity feedback to GOLFIG were strictly correlated with the best outcome observed in patients with autoimmunity signs, increase of central memory T cells, and decrease of regulatory T cells (Treg) in the peripheral blood. We thus investigated a potential correlation between the Treg tumor infiltration at diagnosis and the clinical outcome in a current randomized phase 3 trial aimed to compare the GOLFIG regimen with the standard FOLFOX chemotherapy (GOLFIG-2). An immunohistochemistry study was carried out to quantify the infiltration of Treg/FoxP3+ T lymphocytes in tumor samples of 57 patients enrolled in the GOLFIG-2 trial. Treg tumor infiltration scores were correlated with overall survival, treatment-relative survival, and progression-free survival (PFS). Higher Treg tumor infiltration scores were associated with a better prognosis in the whole series (Treg high score vs. low score: overall survival=mean 43.2 mo vs. 28.6 mo, P=0.0005) and a better outcome after treatment (Treg high score vs. low score: PFS=mean 15.8 mo vs. 8.8 mo, P=0.0009; treatment-relative survival=mean 23.1 mo vs. 18.2 mo, P=0.004). PFS was significantly longer in GOLFIG high versus all other subgroups (mean 18.1 mo vs. 9.9 mo, P=0.01). Our results suggest that a higher FoxP3+ T-lymphocyte tumor infiltration score is a favorable prognostic factor in colon cancer patients undergoing chemo or chemoimmunotherapy.

Adjuvant epirubicin with or without Ifosfamide for adult soft-tissue sarcoma.

This randomized study compared the efficacy of epirubicin-based adjuvant chemotherapy on the disease-free interval (DFI) and overall survival of patients with high-risk soft-tissue sarcomas. After curative surgery, 43 of the 88 enrolled patients were assigned to surgery with or without radiotherapy and 45 to surgery plus chemotherapy (26 epirubicin, 19 epirubicin + ifosfamide) with or without radiotherapy. The trial closed prematurely because of poor patient accrual. There was a statistical significant difference in the 5-year disease-free survival of the patients receiving adjuvant chemotherapy with or without radiotherapy (69%) and that of those treated with surgery with or without radiotherapy (44%) (p = 0.01). The 5-year survival of the patients treated with adjuvant chemotherapy with or without radiotherapy was 72% as against 47% of those treated with surgery with or without radiotherapy (p = 0.06). The power of the study was 0.65 for both the DFI and overall survival. The results of the study suggest a possible advantage of epirubicin-based adjuvant chemotherapy in patients with soft-tissue sarcoma at high risk of relapse.

Treatment of colon and breast carcinoma cells with 5-fluorouracil enhances expression of carcinoembryonic antigen and susceptibility to HLA-A(*)02.01 restricted, CEA-peptide-specific cytotoxic T cells in vitro

Cancer vaccines directed against tumor associate antigen (TAA) have produced encouraging results in preclinical models but not in cancer patients. A major limitation of this strategy is the relative degree of tolerance to these antigens and the low and heterogeneous tumor cell expression of TAA and major histocompatibility complex (MHC). Previous studies have shown that 5‐fluorouracil (5‐FU) can upregulate the expression of membrane‐associated carcino‐embryonic antigen (CEA), and MHC molecules in colon and breast carcinoma cell lines. We have investigated whether this drug can also enhance their sensitivity to the lytic effects of CEA‐peptide specific Cytotoxic T cell lymphocytes (CTL). The CEA peptide‐specific CTLs generated in our laboratory from normal HLA‐A(*)02.01+ donor PBMCs, were able to kill HLA‐A(*)02.01+/CEA+ breast (MCF‐7‐T103) and colon (HLA‐A(*)02.01 gene‐transfected HT‐29 and C22.20) carcinoma cells in HLA‐A(*)02.01 restricted manner. The treatment of target cells with 5‐FU, enhanced their CEA expression and susceptibility to CTL‐mediated lysis. Cold competition assays confirmed these results, thus supporting the hypothesis that immune target cell lysis and 5‐FU mediated enhancement were dependent on CEA peptide presentation by cancer cells. 5‐FU treatment of functionally “mature” CTL after in vitro expansion, did not reduce their cytolytic activity against MT‐2 target cells but, when the anti‐metabolite was added during the immune‐sensitization phase, CTL generation was significantly inhibited. These results provide a rationale for investigating a possible new role of 5‐FU as an immuno targeting amplifier agent in breast and colorectal cancer patients immunized with CEA‐directed cancer vaccines.

Dendritic Cell-Mediated Cross-Presentation of Antigens Derived from Colon Carcinoma Cells Exposed to a Highly Cytotoxic Multidrug Regimen with Gemcitabine, Oxaliplatin, 5-Fluorouracil, and Leucovorin, Elicits a Powerful Human Antigen-Specific CTL Response with Antitumor Activity in Vitro

Gemcitabine, oxaliplatin, leucovorin, and 5-fluorouracil (GOLF) is a novel multidrug regimen inducing high levels of necrosis and apoptosis in colon carcinoma cells. This regimen is also able to promote a process of Ag remodeling including up-regulation of immunotherapy targets like carcinoembryonic Ag (CEA), thymidylate synthase (TS). We have conducted a preclinical study aimed to investigate whether these drug-induced modifications would also enhance colon cancer cell immunogenicity. Several CTL lines were thus generated by in vitro stimulating human HLA-A(*)02.01+ PBMCs, from normal donors and colon cancer patients, with autologous dendritic cells cross-primed with cell lysates of colon cancer cells untreated, irradiated, or previously exposed to different drug treatments including the GOLF regimen. Class I HLA-restricted cytolytic activity of these CTL lines was tested against colon cancer cells and CEA and TS gene transfected target cells. These experiments revealed that CTLs sensitized with GOLF-treated cancer cells were much more effective than those sensitized with the untreated colon carcinoma cells or those exposed to the other treatments. CTL lines sensitized against the GOLF-treated colon cancer cells, also expressed a greater percentage of T-lymphocyte precursors able to recognize TS- and CEA-derived peptides. These results suggest that GOLF regimen is a powerful antitumor and immunomodulating regimen that can make the tumor cells a suitable means to induce an Ag-specific CTL response. These results suggest that a rationale combination of GOLF chemotherapy with cytokine-based immunotherapy could generate a chemotherapy-modulated Ag-specific T-lymphocyte response in cancer patients able to destroy the residual disease survived to the cytotoxic drugs.

Role of gemcitabine-based combination therapy in the management of advanced pancreatic cancer: A meta-analysis of randomised trials

BACKGROUND Pancreatic cancer is the fourth leading cause of cancer-related death worldwide. Gemcitabine is the mainstay treatment for advanced disease. However, almost all up-to-date trials, that evaluated the benefit of gemcitabine-combination schedules, failed to demonstrate an improvement in overall survival (OS). In this study, we performed a systematic review and a meta-analysis of randomised clinical trials (RCTs) to investigate the efficacy and safety of gemcitabine-based combination regimens as compared to gemcitabine alone in the management of pancreatic cancer. METHODS Clinical trials were collected by searching different databases (PubMed, Embase and the Central Registry of Controlled Trials of the Cochrane Library) and abstracts from major cancer meetings. We considered period ranging from January 1997 to January 2012. Primary end-point was OS, secondary end-points were response rate (RR), disease control rate (DCR) and safety. Hazard ratios (HRs) of OS, odds-ratios (ORs) of RR, DCR and risk ratios of grade 3-4 toxicity rates (TRs), were extracted as presented in retrieved studies and used for statistical analysis. Meta-analytic estimates were derived using random-effects model. FINDINGS Thirty-four trials for a total of 10,660 patients were selected and included in the final analysis. The analysis showed that combination chemotherapy confers benefit in terms of OS (HR: 0.93; 95% confidence interval (CI): 0.89-0.97; p=0.001). ORs for both RR and DCR demonstrated a significant advantage for combination therapy (OR for RR: 0.60, 95%CI: 0.47-0.76, p<0.001; OR for DCR: 0.79; 95%CI: 0.66-0.93; p=0.006). Toxicities were more frequent with the combination treatment and significance in terms of risk ratio was reached for diarrhoea (0.53, 95%CI: 0.36-0.79), nausea (0.74, 95%CI: 0.56-0.96), neutropenia (0.71, 95%CI: 0.59-0.85) and thrombocytopenia (0.57, 95%CI: 0.43-0.75). INTERPRETATION The combination chemotherapy as compared to gemcitabine alone significantly improves OS in advanced pancreatic cancer (APC). However, this advantage is marginal whereas the treatment-related toxicity is increased, suggesting the use of gemcitabine-based combination regimens only in selected patient populations. New prospective trials, based on translational approaches and innovative validated biomarkers, are eagerly awaited on this topic.

Immunity feedback and clinical outcome in colon cancer patients undergoing chemoimmunotherapy with gemcitabine + FOLFOX followed by subcutaneous granulocyte macrophage colony-stimulating factor and aldesleukin (GOLFIG-1 Trial).

Purpose: GOLFIG chemoimmunotherapy regimen proved to be a safe and very active chemoimmunotherapy regimen in advanced colon cancer patients. We have thus investigated the immunobiological feedback to the treatment and its possible correlation with the clinical outcome of these patients. Experimental Design: This clinical and immunologic study involved 46 patients, 27 males and 19 females, enrolled in the GOLFIG-1 phase II trial who received gemcitabine (1,000 mg/m2 on days 1 and 15), oxaliplatin (85 mg/m2 on days 2 and 16), levofolinic acid (100 mg/m2 on days 1, 2, 15, and 16), and 5-fluorouracil (400 mg/m2 as a bolus, and 800 mg/m2 as a 24-hour infusion on days 1, 2, 15, and 16) followed by s.c. granulocyte macrophage colony-stimulating factor (100 μg, on days 3-7) and interleukin 2 (0.5 × 106 IU twice a day on days 8-14 and 17-29). Results: The regimen was confirmed to be safe and very active in pretreated patients with metastatic colorectal cancer. A subgroup analysis of these patients revealed a prolonged time to progression and survival in six patients who developed late signs of autoimmunity. A multivariate analysis validated the occurrence of autoimmunity signs as an independent predictor of favorable outcome. A parallel immunologic study detected in the peripheral blood mononuclear cells of these patients a progressive increase in lymphocyte and eosinophil counts, amplification in central memory, a marked depletion of immunosuppressive regulatory T cells, and activation of colon cancer–specific cytotoxic T cells. Conclusions: Our results suggest that immunity feedback to GOLFIG regimen and its antitumor activity are tightly correlated.

Cetuximab ± chemotherapy enhances dendritic cell-mediated phagocytosis of colon cancer cells and ignites a highly efficient colon cancer antigen-specific cytotoxic T-cell response in vitro

Cetuximab is a human/mouse chimeric IgG1 monoclonal antibody (mAb) to epidermal growth factor receptor, approved for colorectal carcinoma treatment in combination with chemotherapy. The immune‐mediated effects elicited by its human fraction of crystallization moiety might critically contribute to the overall anti‐tumor effectiveness of the antibody. We therefore investigated cetuximab ability to promote colon cancer cell opsonization and phagocytosis by human dendritic cells (DCs) that are subsequently engaged in antigen‐cross presentation to cytotoxic T‐lymphocyte (CTL) precursors. Human colon cancer cell lines were evaluated for susceptibility to DC‐mediated phagocytosis before and after treatment with chemotherapy ± cetuximab in vitro. Human DCs loaded with control or drug‐treated cetuximab‐coated colon cancer cells were used to in vitro generate cytotoxic T cell clones from peripheral blood mononuclear cells of human leucocyte antigen‐A(*)02.01+ donors. T‐cell cultures were characterized for immune‐phenotype and tumor‐antigen specific CTL activity. The results confirmed that treatment of tumor cells with irinotecan + L‐folinate + 5‐flurouracil (ILF) or with gemcitabine + ILF increased tumor antigen expression. Moreover, malignant cells exposed to chemotherapy and cetuximab were highly susceptible to phagocytosis by human DCs and were able to promote their activation. The consequent DC‐mediated cross‐priming of antigens derived from mAb‐covered/drug‐treated cancer cells elicited a robust CTL anti‐tumor response. On the basis of our data, we suggest a possible involvement of CTL‐dependent immunity in cetuximab anti‐cancer effects.

Cytotoxic drugs up-regulate epidermal growth factor receptor (EGFR) expression in colon cancer cells and enhance their susceptibility to EGFR-targeted antibody-dependent cell-mediated-cytotoxicity (ADCC).

Cetuximab is a human-murine chimeric IgG1 monoclonal antibody to epidermal growth factor-receptor (EGFR) which exerts synergistic antitumour interactions with several cytotoxic drugs. Therefore, it is presently recommended in combination with chemotherapy in the treatment of colon, head and neck and non-small cell lung cancer. Cetuximab has been designed to inhibit EGFR signalling; however, preclinical evidence suggests that its anti-cancer effects in vivo are also related to the ability of its human IgG1 backbone to trigger immunological mechanisms. Here we have investigated whether the exposure to different cytotoxic drugs may affect the susceptibility of colon cancer cells in vitro to cetuximab immuno-targeting and related lymphokine-activated killer (LAK)-mediated antibody-dependent cell cytotoxicity (ADCC). Five colon cancer cell lines expressing a different k-ras mutational status were evaluated for: (i) EGFR-expression, (ii) susceptibility to LAK cells and (iii) cetuximab-mediated ADCC, before and after exposure to 5-flurouracil (5-FU), gemcitabine (Gem), irinotecan (Iri) alone or in multiple two/three drug combinations. These drugs were able to up-regulate EGFR expression on the surface of all the colon cancer cell lines with a maximal effect observed few hours after the exposure to GILF regimen (Gem, Iri, Levofolinic acid and 5-FU). Chemotherapy was able to greatly enhance the sensitivity to either LAK cells or cetuximab-mediated ADCC in all the colon cancer cell lines with a mechanism independent from k-ras status. The results of our study suggest that chemotherapy may enhance cetuximab-mediated immuno-targeting and ADCC thus providing the rationale to design novel immuno-biochemotherapy regimens.

Early magnesium modifications as a surrogate marker of efficacy of cetuximab-based anticancer treatment in KRAS wild-type advanced colorectal cancer patients

BACKGROUND KRAS wild-type mutational status is necessary but not sufficient to get benefit from epidermal growth factor receptor inhibition. Predictive markers are currently being evaluated. In this study, we investigated early hypomagnesemia as a predictor of efficacy and outcome in terms of time to progression (TtP) and overall survival (OS) in a cohort of patients affected by advanced colorectal adenocarcinoma KRAS wild-type cetuximab-treated. PATIENTS AND METHODS One hundred and forty-three patients affected by stage IV colorectal adenocarcinoma KRAS wild type receiving cetuximab + irinotecan (CTX+IRI) as third-line anticancer treatment and resistant to oxaliplatin- and irinotecan-based chemotherapy were retrospectively included. Magnesium plasma levels were measured before the first day and 7, 14, 21 and 28 days after CTX+IRI infusion. RESULTS The median magnesium basal value showed a statistically significant decrease after the start of CTX+IRI treatment (at 28 days, P < 0.0001). Patients with an early decrease of magnesium levels >50% compared with the basal level had a higher tumor response rate (55.8% versus 16.7%, P < 0.0001), a longer TtP (6.3 versus 3.6, P < 0.0001) and a longer median OS (11.0 versus 8.1, P = 0.002). CONCLUSIONS We have shown that early hypomagnesemia could be a predictor of efficacy and outcome in those patients. Magnesium circulating level is an easy and inexpensive biomarker to routinely be detected in patients treated with cetuximab.