CRC FFPE Blocks with MLH1, PMS2, MSH2, and MSH6: Advancing Colorectal Cancer Research

Explore CRC FFPE blocks with MLH1, PMS2, MSH2, and MSH6 IHC results.

Introduction

Colorectal cancer (CRC) is one of the leading causes of cancer-related morbidity and mortality worldwide. A key factor in CRC progression and treatment outcomes is DNA mismatch repair (MMR) deficiency, which leads to microsatellite instability (MSI). To study these mechanisms effectively, researchers require high-quality FFPE (formalin-fixed paraffin-embedded) tissue blocks annotated with mismatch repair protein expression, including MLH1, PMS2, MSH2, and MSH6.

ArraysBank offers a wide collection of CRC FFPE blocks with detailed clinical and immunohistochemical data, supporting translational research, biomarker validation, and drug development.

The Role of MMR Proteins in Colorectal Cancer

DNA mismatch repair is essential for maintaining genomic stability. Deficiency in MLH1, PMS2, MSH2, or MSH6 results in accumulation of mutations, which can drive tumorigenesis.

• MLH1 – Often silenced by promoter hypermethylation, strongly associated with sporadic MSI-high CRC.

• PMS2 – Works as a partner of MLH1; loss of PMS2 often coincides with MLH1 deficiency.

• MSH2 – A core mismatch repair gene; germline mutations are linked to Lynch syndrome.

• MSH6 – Partner gene of MSH2; loss may occur in Lynch syndrome–associated CRC.

The IHC status of these proteins is a critical diagnostic tool to distinguish sporadic MSI-high CRC from Lynch syndrome, guiding both treatment and genetic counseling.

Features of ArraysBank CRC FFPE Blocks

Our CRC FFPE blocks are carefully collected, preserved, and annotated to support advanced cancer research:

• FFPE tumor tissue blocks with confirmed colorectal adenocarcinoma diagnosis

• Immunohistochemical results for MLH1, PMS2, MSH2, and MSH6

• Clinical metadata including tumor grade, stage, and treatment history (when available)

• High tumor cell content (>20%) and minimal necrosis (<10%)

• Available matched normal tissue in select cases

These well-characterized blocks provide researchers with reproducible and ethically sourced material for molecular studies.

Applications in Research

CRC FFPE blocks with MMR protein annotation are invaluable for multiple research domains:

1. Microsatellite Instability (MSI) Research

   • Study the impact of MLH1, PMS2, MSH2, and MSH6 deficiency on MSI-high CRC.

2. Lynch Syndrome Studies

   • Differentiate hereditary CRC from sporadic forms using IHC results.

3. Biomarker Discovery

   • Identify prognostic and predictive biomarkers linked to DNA repair deficiency.

4. Drug Development

   • Evaluate the efficacy of immunotherapies (e.g., checkpoint inhibitors) in MSI-high colorectal cancers.

5. Educational Use

   • Train pathology residents and researchers in MMR protein analysis through real-world CRC samples.

Quality Assurance

At ArraysBank, quality is ensured through:

• IRB-compliant sourcing and ethical standards

• Pathologist verification of diagnosis and tumor content

• Multi-layer quality control, including H&E and IHC staining review

• Secure storage and FedEx overnight shipping for optimal preservation

Conclusion

CRC FFPE blocks with MLH1, PMS2, MSH2, and MSH6 annotations provide a robust foundation for colorectal cancer research. By offering insights into DNA mismatch repair deficiency, microsatellite instability, and Lynch syndrome, these samples accelerate biomarker validation and drug discovery in oncology.

ArraysBank’s extensive tissue repository—spanning more than 2 million paraffin blocks across 15+ anatomical systems and 50+ anatomic sites—ensures reliable access to high-quality specimens for cutting-edge cancer research.

Learn more about our tissue array and FFPE solutions to support your colorectal cancer studies.