0000000000051843
AUTHOR
Florian Grabellus
Expression of Bax, a pro-apoptotic member of the Bcl-2 family, in esophageal squamous cell carcinoma
Samples of normal esophageal squamous epithelium (n = 10), severe squamous cell dyplasia (n = 22), carcinoma in situ (n = 15), invasive squamous cell carcinoma (n = 172), lymph-node metastasis (n = 21) and 2 permanent esophageal squamous cell carcinoma cell lines were analyzed immunohistochemically for Bax expression using a polyclonal anti-Bax antibody. Immunostaining was evaluated according to a score system (0–8 points) based on the percentage of positive tumor cells and the relative immunostaining intensity. Cytoplasmatic staining for Bax protein was found uniformly in all cell layers of the normal esophageal squamous epithelium. In contrast, a gradual loss of immunoreactivity for Bax w…
Targeting Bcl-2 family proteins modulates the sensitivity of B-cell lymphoma to rituximab-induced apoptosis.
The chimeric monoclonal antibody rituximab is the standard of care for patients with B-cell non-Hodgkin lymphoma (B-NHL). Rituximab mediates complementdependent cytotoxicity and antibodydependent cellular cytotoxicity of CD20-positive human B cells. In addition, rituximab sensitizes B-NHL cells to cytotoxic chemotherapy and has direct apoptotic and antiproliferative effects. Whereas expression of the CD20 antigen is a natural prerequisite for rituximab sensitivity, cell-autonomous factors determining the response of B-NHL to rituximab are less defined. To this end, we have studied rituximab-induced apoptosis in human B-NHL models. We find that rituximab directly triggers apoptosis via the m…