Six low-penetrance SNPs for the estimation of breast cancer heritability: A family-based study in Caucasian Italian patients

Overexpression of RAD50 is the Marker of Poor Prognosis and Drug Resistance in Breast Cancer Patients

BACKGROUND

The prevalence of breast cancer is increasing at an alarming rate and thus demands exploration of the most relevant diagnostic biomarkers. RAD50 is a cancer susceptibility gene that encodes a DNA damage repairing protein. Its role in breast cancer as clinico-pathological specific biomarker has yet to be explored.

OBJECTIVE

This study was aimed to investigate the RAD50 expression and its promoter's methylation level variations in breast invasive carcinoma patients having different clinico-pathological features. This study further explored the mutational spectrum of RAD50 and the correlation of its expression with the survival of patients and the effectiveness of drugs used for treatment.

METHODS

Enrichment analysis of RAD50 was accomplished using the platform of GeneCards. The information regarding RAD50 expression, its promoter methylation and impact on survival of patient was retrieved from TCGA and CPTAC databases. However, the effect of RAD50 expression on tumor's response to various drugs was deduced through the analysis of CCLE and genomic of GDSC dataset.

RESULTS

The promoter hyper-methylation and elevated expression of RAD50 was documented in various subgroups of breast invasive carcinoma. The subjects having low/medium expression levels were observed to survive longer than patients exhibiting high expression of RAD50 except for post-menopausal subjects. The frequency of missense mutations was higher in RAD50 than truncating mutations. Most of the drugs were found to have a positive correlation with RAD50 expression.

CONCLUSION

The status of RAD50 promoter's methylation inversely correlates with the expression level of RAD50. While RAD50 is overexpressed in breast cancer patients and thus makes tumor resistant against many anti-cancer drugs.

Scanning all chromosomal abnormalities with microarray-based comparative genomic hybridization in differential diagnosis of pediatric cancers

OBJECTIVE

Despite conventional histopathological and immunohistochemical methods, difficulties may be experienced in the differential diagnosis of pediatric cancers, especially in small round-cell undifferentiated tumors. In these cases, the determination of chromosomal abnormalities may be helpful. The aim of this study was to evaluate the place of the whole genome array comparative genomic hybridization method in pediatric cancers where difficulty is experienced in differential diagnosis.

METHOD

In Comparative Genomic Hybridization (CGH), 135,000 probes were scanned as 3 probes per gene in all genomes. It was possible to analyze paraffin block tissues obtained from the archive of the Pathology Laboratory of Dr. Behcet Uz Children's Hospital. DNA extraction was made from the paraffin blocks of 24 cases where difficulty had been experienced in making the differential diagnosis and in each case, comparisons with the control samples were made for all anomalies in all chromosomes using microarray technology.

RESULTS

Together with the typically observed chromosomal anomalies, additional derangements with debatable importance were determined.

CONCLUSION

The whole genome CGH method may be useful in pediatric cancers where difficulties are experienced in making differential diagnoses. Since technical difficulties are experienced in the examination of paraffin-embedded tissue samples, storing fresh tissue samples from each tumor will be helpful for genetic and molecular examinations.