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Anti-Claudin 18.2 (clone QR120)

Anti-Claudin 18.2 (clone QR120)

Claudin 18.2 (CLDN18.2) – A Selective Biomarker and Therapeutic Target in Gastrointestinal Cancers
Overview of CLDN18.2
Claudin 18.2 (CLDN18.2) belongs to the claudin family, a group of membrane proteins forming tight junctions that regulate permeability, barrier function, and epithelial layer polarity.
CLDN18.2 is the dominant isoform in normal gastric tissue; however, its expression often persists and undergoes changes during malignant transformation. As a result, CLDN18.2 serves as a highly selective biomarker, frequently exhibiting aberrant expression during the development and progression of various malignancies, particularly:
✔ Gastric cancer (GC)
✔ Esophagogastric junction adenocarcinoma (EGJA)
Due to its tumor-specific expression, CLDN18.2 is being explored as a therapeutic target for GC/EGJA treatment.
Clinical Significance of CLDN18.2 in Gastric and Esophagogastric Junction Cancers
✔ Gastric cancer (GC) is the fifth most diagnosed malignancy and the third leading cause of cancer-related deaths worldwide.
✔ Esophagogastric junction adenocarcinoma (EGJA) is the ninth most common cancer and the sixth leading cause of cancer mortality globally.
✔ In the United States, only 6% of patients with metastatic GC/EGJA survive 5 years post-diagnosis.
✔ The majority of gastric cancers are diagnosed at an advanced or metastatic stage, where surgical intervention (combined with neoadjuvant and adjuvant therapy) is no longer an option.
The Role of CLDN18.2 in Cancer Diagnosis and Therapy
✔ Routine biomarker testing could significantly reduce diagnostic time and improve treatment selection.
✔ Immunohistochemical (IHC) CLDN18 testing is increasingly adopted in clinical practice to identify patients eligible for anti-CLDN18.2 therapy.
CLDN18.2 Expression in Metastases and Other Cancers
✔ CLDN18.2 can be expressed in metastatic gastric adenocarcinoma, including lymph node and distant site metastases.
✔ CLDN18.2 expression has also been observed in:
• Esophageal cancer
• Pancreatic cancer
• Mucinous ovarian carcinoma
• Non-small cell lung cancer (NSCLC)
Given its high specificity and selective expression, CLDN18.2 is emerging as a crucial diagnostic and therapeutic biomarker, particularly in gastrointestinal cancers.

  • Literature

    [1] Angerilli V et al. (2024). Pathol Res Pract. 254:155145.

    [2] Pellino A et al. (2021). J Pers Med. 11(11):1095.

    [3] Tsukita S et al. (2019). Trends Biochem Sci. 44(2):141-52.

    [4] Hu YJ et al. (2013). Mol Biol Rep. 40(11):6123-42.

    [5] Sahin U et al. (2008). Clin Cancer Res. 14(23):7624-34.

  • Advantage of QUARTETT Antibodies

    ADVANTAGES OF RECOMBINANT RABBIT MONOCLONAL ANTIBODIES

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    Key Advantages of Our Next-Generation Recombinant Rabbit Monoclonal Antibodies

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    Recombinant rabbit monoclonal antibodies represent the future of immunohistochemistry, offering unmatched reliability and precision in diagnostic and research settings.

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