A. J. Norton

BACKGROUND: Patients with follicular lymphoma may survive for periods of less than 1 year to more than 20 years after diagnosis. We used gene-expression profiles of tumor-biopsy specimens obtained at diagnosis to develop a molecular predictor of the length of survival. METHODS: Gene-expression profiling was performed on 191 biopsy specimens obtained from patients with untreated follicular lymphoma. Supervised methods were used to discover expression patterns associated with the length of survival in a training set of 95 specimens. A molecular predictor of survival was constructed from these genes and validated in an independent test set of 96 specimens. RESULTS: Individual genes that predicted the length of survival were grouped into gene-expression signatures on the basis of their expression in the training set, and two such signatures were used to construct a survival predictor. The two signatures allowed patients with specimens in the test set to be divided into four quartiles with widely disparate median lengths of survival (13.6, 11.1, 10.8, and 3.9 years), independently of clinical prognostic variables. Flow cytometry showed that these signatures reflected gene expression by nonmalignant tumor-infiltrating immune cells. CONCLUSIONS: The length of survival among patients with follicular lymphoma correlates with the molecular features of nonmalignant immune cells present in the tumor at diagnosis.

The merits of microwave-based antigen retrieval methods for diagnostic immunohistochemistry have recently been emphasized. As such technology has drawbacks for busy routine laboratories, we have investigated an alternative method of heat-mediated antigen retrieval (HMAR), using a domestic pressure cooker as a source of superheating. A simple protocol, with superheating in 0.01 M citrate buffer (pH 6.0) for 2 min, gave results comparable to those obtainable in a microwave oven. The range of antigens retrieved and the antigens for which heating was ineffective matched the published microwave experience. The advantages included the speed of treatment, the reproducibility of results with large batches of slides, the ability to use metal slide racks, and economy of time and equipment costs.

We report on the discovery of WASP-12b, a new transiting extrasolar planet with R <SUB>pl</SUB> = 1.79<SUP>+0.09</SUP> <SUB>-0.09</SUB> R<SUB>J</SUB> and M <SUB>pl</SUB> = 1.41<SUP>+0.10</SUP> <SUB>-0.10</SUB> M <SUB>J</SUB>. The planet and host star properties were derived from a Monte Carlo Markov Chain analysis of the transit photometry and radial velocity data. Furthermore, by comparing the stellar spectrum with theoretical spectra and stellar evolution models, we determined that the host star is a supersolar metallicity ([M/H] = 0.3<SUP>+0.05</SUP> <SUB>-0.15</SUB>), late-F (T <SUB>eff</SUB> = 6300<SUP>+200</SUP> <SUB>-100</SUB> K) star which is evolving off the zero-age main sequence. The planet has an equilibrium temperature of T <SUB>eq</SUB> = 2516 K caused by its very short period orbit (P = 1.09 days) around the hot, twelfth magnitude host star. WASP-12b has the largest radius of any transiting planet yet detected. It is also the most heavily irradiated and the shortest period planet in the literature.