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Evaluation of SNaPshot and Sanger sequencing for the detection of KRAS and NRAS mutations in a sample of Venezuelan patients with colorectal cancer

  • 0Instituto Venezolano de Investigaciones Científicas (IVIC), Unidad de Estudios Genéticos y Forenses (UEGF), Caracas 1020, República Bolivariana de Venezuela.
Ecancermedicalscience +

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January 16, 2025

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January 16, 2025

View abstract on PubMed

Summary

This summary is machine-generated.

The SNaPshot sequencing method accurately detects KRAS and NRAS mutations in colorectal cancer (CRC) tumors. This technique offers improved sensitivity and specificity compared to Sanger sequencing for diagnosing these critical genetic alterations.

Area Of Science

  • Oncology
  • Molecular Biology
  • Genetics

Background

  • Colorectal cancer (CRC) is a significant global health concern, ranking third in men and second in women.
  • Epidermal growth factor receptor (EGFR) signaling is crucial in CRC development; anti-EGFR monoclonal antibody (MAb) therapies improve patient survival.
  • Mutations in KRAS and NRAS oncogenes confer resistance to anti-EGFR MAb therapies by activating alternative signaling pathways.

Purpose Of The Study

  • To evaluate the SNaPshot sequencing method for diagnosing KRAS and NRAS mutations in formalin-fixed, paraffin-embedded (FFPE) colorectal cancer tumor tissues.
  • To compare the diagnostic accuracy, sensitivity, and specificity of SNaPshot sequencing against the Sanger sequencing method.
  • To determine the geographical distribution of KRAS and NRAS gene polymorphisms in Venezuela.

Main Methods

  • DNA was extracted from 33 FFPE colorectal cancer tumor samples.
  • SNaPshot sequencing was employed for mutation detection in exon 2 of KRAS and NRAS genes.
  • Results were compared with those obtained using the Sanger sequencing method.

Main Results

  • KRAS mutations were identified in 27.3% of samples, and NRAS mutations in 15.1% of samples.
  • The SNaPshot method demonstrated superior accuracy, sensitivity, and specificity in detecting single nucleotide polymorphisms compared to Sanger sequencing.
  • The study provided the first geographical distribution of KRAS and NRAS gene polymorphisms in Venezuela; no significant association was found between mutational status and clinical-histopathological variables.

Conclusions

  • SNaPshot sequencing is a highly accurate and sensitive method for detecting KRAS and NRAS mutations in FFPE colorectal cancer tissues.
  • This method offers a significant advantage over Sanger sequencing for routine clinical diagnostics and molecular profiling of CRC.
  • The findings contribute to understanding the genetic landscape of CRC in Venezuela and support the clinical utility of advanced sequencing techniques.

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