Radiation-associated angiosarcoma of the breast: An international multicenter analysis.

INTRODUCTION: Radiation-associated angiosarcoma (RAAS) is a rare and serious complication of breast irradiation. Due to the rarity of the condition, clinical experience is limited and publications on this topic include only retrospective studies or case reports. MATERIALS AND METHODS: All patients diagnosed with RAAS between January 2000 and December 2017 in twelve centers across the Czech Republic and Slovakia were evaluated. RESULTS: Data of 53 patients were analyzed. The median age at diagnosis was 72 (range 44-89) years. The median latency period between irradiation and diagnosis of RAAS was 78 (range 36-172) months. The median radiation dose was 57.6 (range 34-66) Gy. The whole breast radiation therapy with radiation boost to the tumor bed was the most common radiotherapy regimen. Total mastectomy due to RAAS was performed in 43 patients (81%), radical excision in 8 (15%); 2 patients were not surgically treated due to unresectable disease. Adjuvant chemotherapy followed surgical therapy of RAAS in 18 patients, 3 patients underwent adjuvant radiotherapy. The local recurrence rate of RAAS was 43% and the median time from surgery to the onset of recurrence was 7.5 months (range 3-66 months). The 3-year survival rate was 56%, the 5-year survival rate was only 33%. 46% of patients died during the follow-up period. CONCLUSION: The present data demonstrate that RAAS is a rare condition with high local recurrence rate (43%) and mortality (the 5-year survival rate was 33%.). Early diagnosis of RAAS based on biopsy is crucial for treatment with radical intent. Surgery with negative margins constitutes the most important part of the therapy; the role of adjuvant chemotherapy and radiotherapy is still unclear.

Clinical management of secondary angiosarcoma after breast conservation therapy.

AIM: The aim of this paper is to summarize the treatment outputs of secondary angiosarcoma after breast conservation therapy at St. Eizabeth Cancer Centre, Slovakia. BACKGROUND: Angiosarcoma of the breast is a rare but very aggressive malignant tumor of the vascular endothelium, characterized by rapidly proliferating and extensively infiltrating growth. Breast angiosarcoma may occur de novo, or as a complication of radiation therapy, or chronic lymphedema secondary to axillary lymph node dissection for mammary carcinoma. Radiotherapy in the treatment of breast cancer is associated with an increased risk of subsequent sarcoma. MATERIALS AND METHODS: Retrospective study of medical records from the cancer databases was done in order to analyze the secondary breast angiosarcoma. This disease is an iatrogenic condition that warrants close follow-up and judicial use of radiotherapy in breast conserving therapy. Therefore, it is more prevalent in cases treated with radiotherapy, occurring especially in or adjacent to the radiation field. Clinical histories and follow-up data of identified patients after breast conservation therapy of invasive breast cancer were reviewed. In addition, a comprehensive literature review on diagnosis and treatment procedures was done in order to summarize state-of-the-art clinical approach. RESULTS AND DISCUSSIONS: Three cases of secondary angiosarcoma after breast conservation therapy (BCT) were identified among 4600 patients treated at St. Elizabeth Cancer Institute during previous 16 years (1995-2011). Secondary breast angiosarcoma was diagnosed in a median period of 11 years following primary radiotherapy, median age at the time of diagnosis was 75 years. Surgical treatment consisted of radical mastectomy. The first patient, a 56-year-old woman received neoadjuvant chemotherapy (docetaxel + gemcitabin), second one (75 year) was treated by radiotherapy (TD 26 Gy, 2 Gy per fraction), since chemotherapy was not indicated. The last patient (80 year) got adjuvant chemotherapy (paclitaxel). Average follow up of the patients was 31 months. As of 31 July 2012, our patients were doing well without evidence of recurrent disease after treatment. CONCLUSIONS: Angiosarcoma remains a difficult management problem with poor loco-regional and distal control. In our study, an overall incidence rate of secondary breast angiosarcoma is 0.065%. Although the prognosis for this disease is poor (typical survival period is 14.5-34 months with a 5-year survival rate of approximately 15%), all the three patients treated at our institute are alive and disease-free at the end of reported period. Finally, it is assumed that the use of breast conserving therapy will increase the incidence of post-irradiation angiosarcoma but the small difference in risk of subsequent sarcoma of the breast cancer patients receiving radiotherapy does not suppress its benefit.

Activation of dormant bacterial genes by Nonomuraea sp. strain ATCC 39727 mutant-type RNA polymerase.

There is accumulating evidence that the ability of actinomycetes to produce antibiotics and other bioactive secondary metabolites has been underestimated due to the presence of cryptic gene clusters. The activation of dormant genes is therefore one of the most important areas of experimental research for the discovery of drugs in these organisms. The recent observation that several actinomycetes possess two RNA polymerase beta-chain genes (rpoB) has opened up the possibility, explored in this study, of developing a new strategy to activate dormant gene expression in bacteria. Two rpoB paralogs, rpoB(S) and rpoB(R), provide Nonomuraea sp. strain ATCC 39727 with two functionally distinct and developmentally regulated RNA polymerases. The product of rpoB(R), the expression of which increases after transition to stationary phase, is characterized by five amino acid substitutions located within or close to the so-called rifampin resistance clusters that play a key role in fundamental activities of RNA polymerase. Here, we report that rpoB(R) markedly activated antibiotic biosynthesis in the wild-type Streptomyces lividans strain 1326 and also in strain KO-421, a relaxed (rel) mutant unable to produce ppGpp. Site-directed mutagenesis demonstrated that the rpoB(R)-specific missense H426N mutation was essential for the activation of secondary metabolism. Our observations also indicated that mutant-type or duplicated, rpoB often exists in nature among rare actinomycetes and will thus provide a basis for further basic and applied research.

Chromosomally encoded small antisense RNA in Corynebacterium glutamicum.

The first observation of chromosomally encoded small antisense RNA in Corynebacterium glutamicum is reported. Transcription oriented in the reverse direction to the transcription of the genes cg1934 and cg1935 was demonstrated within the chromosomal cg1934-cg1935 intergenic region. The transcription was found to be increased after heat shock. The transcriptional start point of this RNA designated ArnA was localized 21 bp upstream of the cg1935 translational start point by primer extension analysis, when the total RNA was isolated from cells grown at 30 degrees C. After heat shock, the transcriptional start point of an additional species of ArnA RNA was detected 19 bp upstream of the cg1935 translational start point. The stress-response sigma factor SigH was found to be involved in the synthesis of ArnA RNAs. The 3' end of the ArnA RNAs was identified using the 3'-rapid amplification of cDNA ends technique. The length of the two ArnA RNA species was thus determined to be 129 and 131 nt, respectively. The ArnA RNAs were found to overlap the 5'-untranslated region of the transcript of the cg1935 gene coding for a transcriptional regulator of the GntR family. These results suggest that the noncoding ArnA RNAs have a regulatory function.

Plasmid vectors for testing in vivo promoter activities in Corynebacterium glutamicum and Rhodococcus erythropolis.

Novel shuttle promoter-probe vectors replicating in Escherichia coli, Corynebacterium glutamicum, and Rhodococcus erythropolis were constructed on the basis of the C. glutamicum plasmid pCG1. The vectors carry reporter genes coding for fluorescent proteins, which allow the measurement of promoter activities in vivo. The promoter-probe vector pPRE11 contains the rsgfp reporter gene, coding for a variant of green fluorescent protein (GFP) with a red-shifted excitation maximum. To ensure efficient expression of the gfp gene in R. erythropolis from the tested promoters, the promoterless gene gfpuv, with 5' end fusion with the initial six codons of the aph gene and upstream insertion of the aph Shine-Dalgarno sequence, was used as a reporter gene in the promoter-probe vector pEPR1. Insertion of the rfp reference gene, coding for a variant of the red fluorescent protein DsRed.T4 and cloned under the strong constitutive C. glutamicum promoter P-45, into the vector pEPR1 resulted in a new-generation promoter-probe vector (pRAG5). All vectors were tested using a set of mutant P-dapA promoters displaying various transcriptional activities. The vector pRAG5 is suitable for normalized measurements of promoter activities during the growth of bacterial batch cultures because estimation of the GFP-to-red fluorescent protein fluorescence ratio in strains carrying the plasmid pRAG5 with the tested promoters upstream of gfpuv avoids the influence of plasmid copy number variations on the promoter activity assay.