Method for treating colon cancer with tumour-reactive T-lymphocytes

#The invention relates to an immuno-therapeutically method for treating patients suffering from colon cancer, by administering expanded tumour-reactive CD4+ helper and/or CD8+ T-lymphocytes obtainable from one or more sentinel or metinel lymph nodes draining a tumour in the colon or a metastasis arising from a tumour in the colon, wherein the T-lymphocytes are not CD4+ CD25+Hi lymphocytes, i.e. the present invention does not cover regulatory T-lymphocytes.

#Worldwide, colorectal cancer is the third most common cause of death in cancer and approximately one million individuals are diagnosed each year. Despite optimal surgical treatment and modern adjuvant chemotherapy half of patients have recurrences and ultimately die within 5 years from diagnosis. The most important prognostic factors are presence of lymph node or distant metastases, being found in about 50% of all cases. Patients with locoregional lymph node metastases, Duke's C/stage III, have about 60% 5-year survival after surgery, and when distant metastases are present, the 5-year survival rate is less than 10%. The established, adjuvant treatment in stage III patients is 5-Fluorouracil (5-FU)-based chemotherapy, improving absolute 5-year survival by approximately 10%. There is no evidence for a statistically significant survival benefit for chemotherapy in Duke's B/Stage II patients. However, 20% of patients being classified as lymph node negative will suffer from recurrent disease. Some of these patients are likely to be understaged, since it is widely accepted that accurate staging of colon cancer is difficult and heavily dependent on the number of lymph nodes analyzed by the pathologist. The sentinel node, originally defined in penile carcinoma, is the first lymph node to receive lymphatic drainage from a tumour. Sentinel node detection and analysis has recently been applied in colon cancer, improving staging considerably.

#The immune system often appears informed about tumours, as shown by an accumulation of immune cells at tumour sites, which correlates with improved prognosis. Immuno competent cells respond to “danger” signals, which can be provided of growing tumours as a consequence of the genotoxic stress of cell transformation and disruption of the surrounding microenvironment. Under ideal conditions, these signals will induce inflammation, activate innate effector cells with antitumour activity, and stimulate professional antigen-presenting cells (APCs), particularly dendritic cells (DCs), to engulf tumour-derived antigens and migrate to draining lymph nodes to trigger an adaptive response by T and B lymphocytes. Thus, the immune system is capable of recognizing and eliminating tumour cells but unfortunately tumours often interfere with the development and function of immune responses. However, recent advances in cellular and molecular immunology suggest strategies, which may prevent antitumour responses. Briefly, the presence of a tumour indicates that the developing cancer was able to avoid detection or to escape or to overwhelm the immune response. Progressing tumours often exhibit strategies that promote evasion from immune recognition. Examples are physical exclusion of immune cells from tumour sites, poor immunogenicity due to reduced expression of major histocompatibility complex (MHC) or costimulatory proteins, and disruption of natural killer (NK) and natural killer T (NKT) cell recognition. Further, some tumours prevent triggering of an inflammatory response by secreting proteins such as interleukin 10 (IL-10) or vascular endothelial growth factor (VEGF) that interfere with DC activation and differentiation, or by blocking the production of proinflammatory molecules by increasing expression of the STAT3 protein. Even if a response is induced, tumour cells may escape elimination by losing targeted antigens, rendering tumour-reactive T cells anergic, inducing regulatory T cells, or specifically deleting responding T cells. The tumour that finally develops reflects selection of poorly immunogenic and/or immune-resistant malignant cells.

#FIG. 1 illustrates that the sentinel node is the natural primary site for the presentation and activation of T cell reactivity towards tumour antigen.

#FIG. 2 shows that initially sentinel node lymphocytes are activated with tumour antigen and low dose IL-2 resulting in activation and expression of the activation marker CD25 (Top panel). The end of phase I activation phase is defined by the decreased number of CD4+ T cells expressing CD25 (Bottom panel). When less than 5% of the CD4+ T cells express CD25 phase II is initiated with restimulation with antigen.

#FIG. 3 illustrates that Phase I and Phase II activation results in expansion and enrichment of CD4+ T helper cells.

#The following examples tend to illustrate the invention without limiting it in any way.

#Methods

#Identification and Removal of Sentinel and Metinel Lymph Nodes from Colon Cancer Patients: