Therapy of streptozotocin induced diabetes with a bifunctional antibody that delivers vinca alkaloids to IL-2 receptor positive cells

Bispecific antibody conjugates in therapeutics

Bispecific monoclonal antibodies have drawn considerable attention from the research community due to their unique structure against two different antigens. The two-arm structure of bsMAb allows researchers to place a therapeutic agent on one arm while allowing the other to specifically target the disease site. The therapeutic agent can be a drug, toxin, enzyme, DNA, radionuclide, etc. Furthermore, bsMAb may redirect the cytotoxicity of immune effector cells towards the diseased cells or induce a systemic immune response against the target. BsMAb holds great promise for numerous therapeutic needs in the light of: (1) recent breakthroughs in recombinant DNA technology, (2) the increased number of identified disease targets as the result of the completion of human genomic map project, and (3) a better understanding of the mechanism of human immune system. This review focuses on therapeutic applications and production of bsMAb while providing the up-to-date clinical trial information.

BRCA1 partially reverses the transforming activity of the ras oncogene

The BRCA1 gene is associated with hereditary breast and ovarian cancers. BRCA1 fits the model of a classic tumor suppressor gene, a hypothesis supported by recent work demonstrating that expression of BRCA1 inhibits growth of breast and ovarian cancer cell lines. The present study was designed to test the potential of BRCA1 to reverse the transforming activity of the ras oncogene. The v-Ha ras oncogene was cloned downstream of the retrovirus LTR and stably expressed in Rat-1 cells (Rat-1/ras). Rat-1/ras (R/R) cells were fully transformed as indicated by change in morphology, colony formation in soft-agarose and tumor induction in nude mice. BRCA1 was stably expressed in R/R cells under the CMV promoter (R/R-BRCA1). The expression of ras and BRCA1 was confirmed by Western blot using monoclonal antibodies (mAbs) specific to ras and BRCA1, respectively. R/R-BRCA1 cells grew slower than the negative control, which was R/R cells transfected with vector alone (R/R-pCEP4). R/R-BRCA1 cells generated approximately 5 to 10 times less colonies in a soft-agarose assay compared to the negative control. When injected into nude mice, R/R-BRCA1 cells exhibited a delayed onset of tumorigenesis and generated smaller tumors compared to R/R or R/R-pCEP4 cells. These data strongly suggest that BRCA1 partially reverses the transforming activity of the v-Ha ras oncogene indicating that BRCA1 can bypass the effects of the v-Ha ras oncogene on cell growth. BRCA1, therefore, may be used in therapy of tumors arising due to activation of v-Ha ras oncogene.