Suppression of Akt-mTOR pathway-a novel component of oncogene induced DNA damage response barrier in breast tumorigenesis.

DNA damage has been thought to be directly associated with the neoplastic progression by enabling mutations in tumor suppressor genes and activating/and amplifying oncogenes ultimately resulting in genomic instability. DNA damage causes activation of the DNA damage response (DDR) that is an important cellular mechanism for maintaining genomic integrity in the face of genotoxic stress. While the cellular response to genotoxic stress has been extensively studied in cancer models, less is known about the cellular response to oncogenic stress in the premalignant context. In the present study, by using breast tissues samples from women at different risk levels for invasive breast cancer (normal, proliferative breast disease and ductal carcinoma in situ) we found that DNA damage is inversely correlated with risk of invasive breast cancer. Similarly, in MCF10A based in vitro model system where we recapitulated high DNA damage conditions as seen in patient samples by stably cloning in cyclin E, we found that high levels of oncogene induced DNA damage, by triggering inhibition of a major proliferative pathway (AKT), inhibits cell growth and causes cells to die through autophagy. These data suggest that AKT-mTOR pathway is a novel component of oncogene induced DNA damage response in immortalized 'normal-like' breast cells and its suppression may contribute to growth arrest and arrest of the breast tumorigenesis.

Tetramer guided, cell sorter assisted production of clinical grade autologous NY-ESO-1 specific CD8(+) T cells.

BACKGROUND: Adoptive T cell therapy represents an attractive modality for the treatment of patients with cancer. Peripheral blood mononuclear cells have been used as a source of antigen specific T cells but the very low frequency of T cells recognizing commonly expressed antigens such as NY-ESO-1 limit the applicability of this approach to other solid tumors. To overcome this, we tested a strategy combining IL-21 modulation during in vitro stimulation with first-in-class use of tetramer-guided cell sorting to generate NY-ESO-1 specific cytotoxic T lymphocytes (CTL). METHODS: CTL generation was evaluated in 6 patients with NY-ESO-1 positive sarcomas, under clinical manufacturing conditions and characterized for phenotypic and functional properties. RESULTS: Following in vitro stimulation, T cells stained with NY-ESO-1 tetramer were enriched from frequencies as low as 0.4% to >90% after single pass through a clinical grade sorter. NY-ESO-1 specific T cells were generated from all 6 patients. The final products expanded on average 1200-fold to a total of 36 billion cells, were oligoclonal and contained 67-97% CD8(+), tetramer(+) T cells with a memory phenotype that recognized endogenous NY-ESO-1. CONCLUSION: This study represents the first series using tetramer-guided cell sorting to generate T cells for adoptive therapy. This approach, when used to target more broadly expressed tumor antigens such as WT-1 and additional Cancer-Testis antigens will enhance the scope and feasibility of adoptive T cell therapy.

Invasive paget disease of the breast: clinicopathologic study of an underrecognized entity in the breast.

Mammary Paget disease (MPD) is considered an intraepidermal manifestation of an underlying mammary carcinoma. In contrast to extramammary Paget disease, invasion of mammary Paget cells into the dermis (invMPD) has not been reported, except for 2 cases described in Rosen's textbook. Our study was designed to identify the presence of dermal invasion of mammary Paget cells and characterize the associated clinicopathologic features. Slides from 146 MPD patients were retrieved. Six cases of invMPD were identified. One case of invMPD was not associated with an underlying breast cancer, 1 was associated with invasive ductal carcinoma (IDC), 1 with ductal carcinoma in situ (DCIS) with microinvasion, and 3 with DCIS only. The underlying breast carcinomas was separate from the area of invMPD. The depth of invasion, measured from the dermal-epidermal junction to the focus of deepest invasion, ranged from 0.02 to 0.9 mm. The horizontal extent ranged from 0.01 to 4.0 mm. Lymph node with isolated tumor clusters was present in case 1, which had no underlying carcinoma but had the greatest extent of invasion, and in case 3, which had DCIS with microinvasion. One patient (case 1) died of unrelated causes 2 years later, and the remaining patients were alive without disease at last follow-up. In summary, we describe 6 cases of MPD with invasion of Paget cells into the dermis and provide histopathologic criteria for the diagnosis of this rare and underrecognized entity. Further studies are required to determine whether invasion in MPD has clinical significance.