Quantitative analysis of plasma DNA in anal cancer patients

INTRODUCTION: The availability and non-invasiveness of circulating cell-free DNA (cfDNA) opens up new possibilities for real-time serial testing. The relationship between cfDNA concentration, clinical factors and suitability for monitoring was analyzed in patients with newly diagnosed anal squamous cell carcinoma (ASCC). MATERIAL AND METHODS: Blood samples were collected at several points during and after treatment. Patients were homogeneously treated with chemoradiotherapy. RESULTS: The concentration of cfDNA strongly correlated with the tumor volume (r = 0.9, p = 0.00006) and number of neutrophils (r = 0.706, p = 0.0069). Monitoring of cfDNA levels during treatment showed an increase after initiation of therapy, a peak at the end of treatment with significantly higher values for advanced than in T1/T2 tumors, and a decrease (T3/T4) during follow-up. However, neither the concentration of cfDNA before treatment nor its changes correlated with the response to chemoradiotherapy. There was no association between baseline cfDNA levels and T, N, age and gender. CONCLUSIONS: Substantial changes in plasma cfDNA content can be observed after chemoradiotherapy for ASCC. However, the small number of cases studied makes it difficult to assess the usefulness of the cfDNA test

Circulating HPV16 DNA in Blood Plasma as Prognosticator and Early Indicator of Cancer Recurrence in Radio-Chemotherapy for Anal Cancer

Background: Implementation of anal squamous cell carcinoma (ASCC) treatment modifications requires reliable patient risk stratification. The circulating tumor–related human papillomavirus type 16 (ctHPV16) may play a role in predicting survival or assessing treatment response. Methods: The study included 62 ASCC patients treated with chemoradiotherapy. A threshold of 2.5 was used to determine the maximum standardized uptake value (SUVmax). The ctHPV16 viral load (VL) was quantified by qPCR. Results: In the multivariate Cox analysis, lower SUVmax (p = 0.047) and ctHPV16–positive (p = 0.054) proved to be independent prognostic factors for favorable overall survival (OS). In the subgroup with the higher SUVmax, ctHPV16 and nodal (N) status were independent prognostic factors with p = 0.022 for ctHPV16 and p = 0.053 for N. The best survival rate (95%) presented ctHPV16–positive/N–negative patients. High ctHPV16 VL tended to be slightly specific for patients younger than 63 years (p = 0.152). The decrease in ctHPV16 VL to undetectable level after the end of treatment correlated with the overall clinical response. Conclusions: A prognostic stratification by SUVmax, ctHPV16 and N–positive status allows consideration of more aggressive treatment in high–risk patients (those with high SUVmax, ctHPV16–negative, and N–positive) or de–intensification of therapy in low–risk patients (those with low SUVmax, ctHPV16–positive and N–negative). However, prospective clinical trials on a large group are needed

Expression of a constitutively active mutant of heat shock factor 1 under the control of testis-specific hst70 gene promoter in transgenic mice induces degeneration of seminiferous epithelium.

Heat shock activates in somatic cells a set of genes encoding heat shock proteins which function as molecular chaperones. The basic mechanism by which these genes are activated is the interaction of the specific transcription factor HSF1 with a regulatory DNA sequence called heat shock element (HSE). In higher eukaryotes HSF1 is present in unstressed cells as inactive monomers which, in response to cellular stress, aggregate into transcriptionally competent homotrimers. In the present paper we showed that the expression of a transgene encoding mutated constitutively active HSF1 placed under the control of a spermatocyte-specific promoter derived from the hst70 gene severely affects spermatogenesis. We found the testes of transgenic mice to be significantly smaller than those of wild-type males and histological analysis showed massive degeneration of the seminiferous epithelium. The lumen of tubules was devoid of spermatids and spermatozoa and using the TUNEL method we demonstrated a high rate of spermatocyte apoptosis. The molecular mechanism by which constitutively active HSF1 arrests spermatogenesis is not known so far. One can assume that HSF1 can either induce or repress so far unknown target genes involved in germ cell apoptosis