Neoplasms have been reported to regress in patients subsequent to acute streptococcal infec tions. Treatment of human tumors with an in duced bacterial infection was attempted in 1868 by Busch (2), who had observed clinical improve ment in cancer patients following an attack of erysipelas. Fehleisen (7) established streptococci as the causative agents of erysipelas and obtained encouraging resu...

The cytolethal distending toxins (CDTs) comprise a family of intracellular-acting bacterial protein toxins whose actions upon eukaryotic cells result in several consequences, the most characteristic of which is the induction of G(2)/M cell cycle arrest. Most CDTs are hetero-tripartite assemblies of CdtA, CdtB, and CdtC, with CdtB required for CDT-mediated cell cycle arrest. Several lines of evi...

The connection between bacterial pathogens and unfolded protein response (UPR) is poorly explored. In this review we highlight the evidence showing that group A streptococcus (GAS) induces endoplasmic reticulum (ER) stress and UPR through which it captures the amino acid asparagine (ASN) from the host. GAS acts extracellularly and during adherence to host cells it delivers the hemolysin toxins;...

Bacterial pathogens utilize pore-forming toxins or sophisticated secretion systems to establish infection in hosts. Recognition of these toxins or secretion system by nucleotide-binding oligomerization domain leucine-rich repeat proteins (NLRs) triggers the assembly of inflammasomes, the multiprotein complexes necessary for caspase-1 activation and the maturation of inflammatory cytokines such ...

In his book The Sleepwalkers, Arthur Koestler commented on how scientific progress has evolved along much more irregular paths than generally realized. During the past 100 years, deciphering the pathogenic effects of microorganisms and discovering the many important bacterial toxins represent another case Koestler might have drawn. Some of the most important achievements in the loo-year story o...

Targeted toxins, also known as immunotoxins or cytotoxins, are recombinant molecules that specifically bind to cell surface receptors that are overexpressed in cancer and the toxin component kills the cell. These recombinant proteins consist of a specific antibody or ligand coupled to a protein toxin. The targeted toxins bind to a surface antigen or receptor overexpressed in tumors, such as the...