Polymorphisms in MDM2 and TP53 Genes and Risk of Developing Therapy-Related Myeloid Neoplasms

One of the most severe complications after successful cancer therapy is the development of therapy-related myeloid neoplasms (t-MN). Constitutional genetic variation is likely to impact on t-MN risk. We aimed to evaluate if polymorphisms in the p53 pathway can be useful for predicting t-MN susceptibility. First, an association study revealed that the Pro variant of the TP53 Arg72Pro polymorphism and the G allele of the MDM2 SNP309 were associated with t-MN risk. The Arg variant of TP53 is more efficient at inducing apoptosis, whereas the Pro variant is a more potent inductor of cell cycle arrest and DNA repair. As regards MDM2 SNP309, the G allele is associated with attenuation of the p53 apoptotic response. Second, to evaluate the biological effect of the TP53 polymorphism, we established Jurkat isogenic cell lines expressing p53Arg or p53Pro. Jurkat p53Arg cells presented higher DNA damage and higher apoptotic potential than p53Pro cells, after treatment with chemotherapy agents. Only p53Pro cells presented t(15;17) translocation and del(5q). We suggest that failure to repair DNA lesions in p53Arg cells would lead them to apoptosis, whereas some p53Pro cells, prone to cell cycle arrest and DNA repair, could undergo misrepair, generating chromosomal abnormalities typical of t-MN.

Consequences of quality of reduction on osteosynthesis complications and quality of life in elderly patients with subtrochanteric fracture

OBJECTIVE

To compare results in terms of orthopaedic complications and quality of life in elderly patients with subtrochanteric fracture treated with intramedullary nailing according to fracture reduction status.

PATIENTS AND METHODS

A prospective cohort study including 90 elderly patients with subtrochanteric fractures of the femur treated with a cephalomedullary nail, with a minimum 1-year follow up. The inclusion criteria were: aged 60 years or older, without severe cognitive dysfunction and independent ambulatory capability before the fracture. We defined 3different groups in relation to fracture reduction status: good, acceptable and poor, according to modified criteria from Baumgartner et al. We compared clinical and surgical characteristics and healthy quality of life, social function and mobility according to the EQ-5D, Jensen Index and Mobility Score of Parker and Palmer questionnaires.

RESULTS

We found differences in time to union, better in the good reduction group (P=.002); need for open reduction, more frequent in the good reduction group (P<.001), and in postoperative complications, more frequent in the poor reduction group (P=.001). We found no significant differences between the 3groups regarding scores in quality of life, social function and mobility.

CONCLUSIONS

Reduction in subtrochanteric fractures in older people is key to obtaining better clinic and surgical results, improving time to union and decreasing surgical complications. Exposure of the focus fracture seems to be a safe manoeuvre. Quality of life had substantially deteriorated n these patients, but a there was a tendency, although not statistically significant, for it to improve in patients after good surgical reduction.