A laser-capture microdissection technique was used to pluck individual breast-cancer epithelial cells and surrounding stromal cells from pathology slides for studies of the TP53 gene and loss of heterozygosity across the genome. Mutations of the gene and loss of heterozygosity were found in normal-appearing stromal cells, findings that were associated with the presence of lymph-node metastases. These results suggest that genetic alterations in cells of the microenvironment accelerate the spread of a tumor.

TP53, the gene for the tumor-suppressor protein p53, is the most commonly mutated gene in cancer cells. In this study of head and neck cancer, about half the tumors had a TP53 mutation. The presence of mutations that could disrupt the binding of p53 to a DNA target had the strongest association with decreased survival. The results indicate that a disruptive mutation of TP53 is an independent risk factor for death among patients with head and neck cancer.

This study examines the toxicity of immunosuppressive regimens in renal-transplant recipients. A regimen containing mycophenolate mofetil, daclizumab, low-dose tacrolimus, and corticosteroids appeared to be the most effective with respect to the glomerular filtration rate, allograft survival, and acute rejection, as compared with regimens containing dacluzimab induction plus either low-dose cyclosporine or low-dose sirolimus and with standard-dose cyclosporine without induction.

In this randomized trial comparing telbivudine and lamivudine in patients with chronic hepatitis B, telbivudine was associated with higher rates of response at 1 year among HBeAg-positive patients (75.3% vs. 67.0%, P=0.005); the rates of response to telbivudine and lamivudine among HBeAg-negative patients were similar (75.2% and 77.2%, respectively; P=0.62). Telbivudine was associated with elevated creatine kinase levels.