[New systemic therapies in oncology].

These last decades showed important progress in cancer systemic therapies. A better understanding of the differences between cancer cells and normal cells lead to the emergence of targeted therapies. These treatments interfere with different specific molecules playing a critical role in tumour growth or progression.

[Present chemoprevention and future vision].

Cancer chemoprevention is defined as the use of natural or synthetic agents to reverse, suppress or prevent carcinogenic progression to invasive cancer. The success of several clinical trials within high-risk patients suggests that chemoprevention is a rational and promising strategy. This review will resume the principal molecular mechanisms of chemoprevention and discuss results and clinical outcome of selected clinical trials.

[Cancer screening: when and how?].

Advances in cancer biology have led to the development of screening tests that allow an early diagnosis. Cancer screening is not just the matter of a single individual patient, it is a matter of public health. Screening is commonly viewed as of no harm, when in fact harms are associated with the majority of cancer screening tests.

Nature of a paramyxovirus replication promoter influences a nearby transcription signal.

The genomic and antigenomic 3' ends of the Sendai virus replication promoters are bi-partite in nature. They are symmetrically composed of leader or trailer sequences, a gene start (gs) or gene end (ge) site, respectively, and a simple hexameric repeat. Studies of how mRNA synthesis initiates from the first gene start site (gs1) have been hampered by the fact that gs1 is located between two essential elements of the replication promoter.

Given the opportunity, the Sendai virus RNA-dependent RNA polymerase could as well enter its template internally.

The negative-stranded RNA viral genome is an RNA-protein complex of helicoidal symmetry, resistant to nonionic detergent and high salt, in which the RNA is protected from RNase digestion. The 15,384 nucleotides of the Sendai virus genome are bound to 2,564 subunits of the N protein, each interacting with six nucleotides so tightly that the bases are poorly accessible to soluble reagents. With such a uniform structure, the question of template recognition by the viral RNA polymerase has been raised.