Cyclin D1 as a universally expressed mantle cell lymphoma-associated tumor antigen for immunotherapy

Mantle cell lymphoma (MCL) accounts for 5-10% of all non-Hodgkin lymphomas and has the worst prognosis among all lymphomas. The hallmark of MCL is a t(11;14) translocation that results in overexpression of cyclin D1 by tumor cells of virtually all patients. In this study, we examined whether cyclin D1 could be an effective tumor-associated antigen for immunotherapy. We identified cyclin D1 peptides for HLA-A(*)0201 and generated peptide-specific CD8(+) T-cell lines from HLA-A(*)0201(+) blood donors and MCL patients. These cell lines proliferated in response to cyclin D1 peptide-pulsed stimulatory cells. Moreover, the T cells efficiently lysed peptide-pulsed but not unpulsed T2 cells and autologous dendritic cells; cyclin D1(+) and HLA-A(*)0201(+) human MCL lines MINO, SP53, Jeko-1 and Granta 519; and more importantly, HLA-A(*)0201(+) primary lymphoma cells from MCL patients. No killing was observed with HLA-A(*)0201(-) primary lymphoma cells or HLA-A(*)0201(+) normal blood cells, including B cells. These results indicate that these T cells are potent cytotoxic T cells and recognize cyclin D1 peptides naturally presented by patient lymphoma cells in the context of HLA-A(*)0201 molecules. Taken together, our work identifies cyclin D1 as a potentially important antigen for immunotherapy of MCL.

Mediastinal lymph node dissection affects survival in patients with stage I non-small cell lung cancer

BACKGROUND

The therapeutic value of mediastinal lymph node dissection (LND) for early-stage non-small cell lung cancer (NSCLC) remains controversial. We conducted a retrospective study to investigate the impact of mediastinal LND on survival in patients with stage I NSCLC.

METHODS

Clinical data of patients with stage I NSCLC who were treated with surgical resection during a period of ten years were reviewed. The patients were categorized into lobectomy (or pneumonectomy) combined with mediastinal LND or lymph node sampling (LNS) according to the record of their operative procedures. The Kaplan-Meier method was used for survival analysis. Cox proportional hazards model was used for multivariate analysis.

RESULTS

Of the 319 patients who were included in the study, 139 patients received mediastinal LND, while 180 underwent LNS. There was a significant difference in overall survival (OS) between the group with LND and the group with LNS (5-year survival rate: 76.4 % vs. 65.9 %, P = 0.015 by log rank test). Multivariate analysis showed that lymph node dissection (RR = 0.548, 95 %CI: 0.350 - 0.858, P = 0.009), together with the stage, significantly influenced overall survival.

CONCLUSIONS

Lobectomy combined with mediastinal LND can improve survival in patients with stage I NSCLC. It should be performed in all patients with clinical stage I NSCLC.

Proposed structural models of human factor Va and prothrombinase

BACKGROUND

The prothrombinase complex consists of factor Xa, FVa, calcium ions, and phospholipid membrane. The prothrombinase complex plays a key role in the blood coagulation process.

OBJECTIVE

To derive solvent-equilibrated models of human FVa and the prothrombinase complex.

METHODS

Several modeling techniques have been employed, including homology modeling, protein-protein docking, and molecular dynamics simulation methods, to build the structural models.

RESULTS AND CONCLUSIONS

We found, upon simulation, a possibly significant shift towards planarity of the five FVa domains. To estimate a prothrombinase structure, we docked an FXa model to the equilibrated FVa model using experimental data as docking filters. We found that simulation of the docked complex led to some changes in the protein-protein contacts, but not buried surface area, as compared to the initial docking model. Possible locations of prothrombin binding to prothrombinase are indicated.