Genetic Modification Approaches for Parasporins Bacillus thuringiensis Proteins with Anticancer Activity.

Bacillus thuringiensis (Bt) is a bacterium capable of producing Cry toxins, which are recognized for their bio-controlling actions against insects. However, a few Bt strains encode proteins lacking insecticidal activity but showing cytotoxic activity against different cancer cell lines and low or no cytotoxicity toward normal human cells. A subset of Cry anticancer proteins, termed parasporins (PSs), has recently arisen as a potential alternative for cancer treatment. However, the molecular receptors that allow the binding of PSs to cells and their cytotoxic mechanisms of action have not been well established. Nonetheless, their selective cytotoxic activity against different types of cancer cell lines places PSs as a promising alternative treatment modality. In this review, we provide an overview of the classification, structures, mechanisms of action, and insights obtained from genetic modification approaches for PS proteins.

Composite lymphoma: EBV-positive classic Hodgkin lymphoma and peripheral T-cell lymphoma: a case report.

Composite lymphomas are rare and defined as hematopoietic neoplasms with more than 1 malignant lymphomatous clone showing different phenotypic features. Of all possible combinations between non-Hodgkin lymphomas, B cell or T cell, and Hodgkin lymphoma, the least frequent are the ones combining T-cell non-Hodgkin lymphoma and classic Hodgkin lymphoma. We report a case of a 55-year-old woman with cervical and mediastinal lymphadenopathy, fever, weight loss, and night sweats. A cervical lymph node biopsy revealed a composite lymphoma with classic Hodgkin lymphoma and peripheral T-cell lymphoma components. The bone marrow was not involved. The patient refused treatment and died of disease progression 2 months after diagnosis. The biopsied lymph node showed 2 distinct populations, one composed of large cells including typical Reed-Sternberg cells and their variants, with expression of CD30, CD15, PAX5, and LMP-1. The other component was more abundant and comprised polymorphic medium-sized cells with convoluted nuclei; CD3, CD5, CD2, and CD4 expression; and negativity for CD30, cytotoxic granules, and B-cell markers. Epstein-Barr virus DNA of subtype A was identified only in the Hodgkin cells. Clonal T-cell receptor gamma and beta gene rearrangements were detected in the T-cell component, whereas monoclonal immunoglobulin H gene rearrangement was found in the Hodgkin cells.

Autoimmune lymphoproliferative syndrome in a patient with a new minimal deletion in the death domain of the FAS gene.

We present a case of autoimmune lymphoproliferative syndrome (ALPS) caused by a previously undescribed minimal deletion in the death domain of the FAS gene. ALPS is an uncommon disease associated with an impaired Fas-mediated apoptosis. The patient presented with a history of splenomegaly since 4 months of age, associated with cervical lymphadenopathy, which improved with oral corticosteroid treatment. Relevant laboratory findings were the presence of anemia, thrombocytopenia, and positive direct and indirect Coombs tests. He was not an offspring of consanguineous parents. Two cervical lymph node biopsies were performed, at 4 years and at 6 years of age. In both lymph nodes, there was marked paracortical expansion by lymphocytes in variable stages of immunoblastic transformation and a very high cell proliferating index. Some clear cells were also present, raising the suspicion of malignant lymphoma. In one of the lymph nodes, there was also a focus rich in large histiocytes with round nuclei and emperipolesis, consistent with focal Rosai-Dorfman disease. Immunostaining showed numerous CD3+ cells, many of which were double-negative (CD4- CD8-) and expressed CD57, especially around the follicles. Molecular studies of the lymph node biopsy showed a point deletion (4-base pair deletion) in exon 9 of the FAS gene (930del TGCT), which results in 3 missense amino acids.