GSE42128

• Mammography is the current gold standard for breast cancer detection, but can have false negative rates of up to 20%.

• The miRNA profiles between sera and the corresponding matched tumor were largely dissimilar.
• There were only 7 common significant miRNAs that were overexpressed in both breast cancer tumors and sera from patients with breast cancer, and one miRNA that was downregulated in both sample types.
• Another 13 miRNAs were dysregulated in breast cancer sera and tumors, but in opposite directions. Hence, circulating
  miRNAs are not highly similar to those within breast cancer cells, suggesting that some miRNAs are released into the circulation selectively.

• Among known tumor-derived miRNAs, mir-145 and miR-21 are amongst the most consistently detected and are hence very attractive candidates for clinical application. 

• miR-1, miR-92a, miR-133a, and miR-133b were identified as the most important diagnostic markers.
• Intracellularly, these four miRNAs seem to play tumor suppressor roles in cancer cells.

• GSE42128 has three datasets. We just analyzed the dataset with 280 miRNAs.
• A classification model has been built using Trainset. The selected probes were:
  1. hsa-mir-1
  2. hsa-mir-576-5p
  3. hsa-mir-142-5p
  4. hsa-mir-185

• The model has been tested using Testset.