Depreotide | CAS No. 161982-62-3

Description

Product Description

Depreotide (CAS No. 161982-62-3) is a synthetic somatostatin analog peptide, specifically engineered for its high affinity to somatostatin receptors (SSTRs), which are overexpressed in many tumors, including neuroendocrine tumors, lymphomas, and lung cancers. Its most recognized application is as a radiopharmaceutical precursor, where it is labeled with technetium-99m (99mTc) to form 99mTc-depreotide, a highly effective molecular imaging agent for nuclear medicine research.

Background on Somatostatin Receptors in Cancer Imaging

Somatostatin is a natural neuropeptide that regulates hormone secretion and cell proliferation. Tumors often overexpress SSTR subtypes (particularly SSTR2, SSTR3, and SSTR5), making them excellent biomarkers for molecular imaging and targeted radionuclide therapy. Depreotide was designed to mimic somatostatin’s binding profile, with enhanced stability and radiolabeling compatibility.

Depreotide in Imaging Applications

• 99mTc-depreotide was developed as a diagnostic radiopharmaceutical, widely studied in oncology research.

• It allows visualization of tumors by binding to somatostatin receptor-positive tissues, providing non-invasive imaging data.

• Clinical research has evaluated its utility in lung cancer, lymphoma, and neuroendocrine tumor imaging, often compared with other radiolabeled peptides like octreotide derivatives.

Research Applications

1. Oncology Research: Imaging tumor tissues expressing somatostatin receptors.

2. Nuclear Medicine Development: Precursor peptide for labeling with 99mTc, serving as a basis for new imaging agents.

3. Pharmacokinetics & Biodistribution Studies: Research on peptide-based imaging agent clearance and organ uptake.

4. Radionuclide-Drug Synthesis: Model compound in the development of radiolabeled peptides for diagnostics and therapy.

5. Comparative Radiopharmaceutical Research: Evaluated alongside newer agents like 68Ga-DOTA-peptides to understand improvements in receptor-targeting.

Advantages

• High affinity to somatostatin receptors (SSTR2 > SSTR3/5).

• Technetium-99m labeling compatibility, providing gamma-emitting tracer properties.

• Rapid clearance from non-target tissues, increasing tumor-to-background contrast.

• Synthetic stability, enabling reproducible results in preclinical studies.

In summary, Depreotide is a research-grade peptide analog that plays an essential role in tumor imaging, radionuclide-drug design, and nuclear medicine research.

Product Specifications

Extended Specification Notes

• Molecular Design: Depreotide retains somatostatin’s receptor binding while enhancing stability and radiolabeling efficiency.

• Radiolabeling Properties: Its structure is optimized for 99mTc chelation, ensuring stable complexes in vivo.

• Purity: ≥98% guarantees minimal interference in imaging and biodistribution studies.

• Applications: Preclinical nuclear medicine studies, receptor affinity assays, and experimental tumor imaging models.

Mechanism of Action

Depreotide exerts its biological activity through high-affinity binding to somatostatin receptors (SSTRs) expressed on tumor cells and neuroendocrine tissues.

Stepwise Mechanism

1. Somatostatin Receptor Binding:
   Depreotide binds selectively to SSTR2, SSTR3, and SSTR5, initiating receptor-mediated uptake in tumor tissues.

2. Radiolabeling with Technetium-99m:
   When complexed with 99mTc, Depreotide becomes a gamma-emitting tracer, enabling single-photon emission computed tomography (SPECT) imaging.

3. Tumor Localization:
   The radiolabeled peptide accumulates in SSTR-positive tumors, providing high-contrast imaging compared to surrounding normal tissue.

4. Clearance Profile:
   Depreotide shows rapid renal clearance, reducing background noise and enhancing imaging specificity.

5. Comparison to Other Analogs:
   Unlike older octreotide derivatives, Depreotide demonstrated balanced receptor affinity and stable technetium binding, which made it an important first-generation imaging tool before the advent of 68Ga-DOTA peptides.

Research Implications

• Useful for studying receptor expression in oncology models.

• Provides a platform for developing novel radionuclide-drugs.

• Aids in understanding pharmacokinetics and biodistribution of peptide-based imaging tracers.

  

Side Effects (Research Context)

In preclinical and clinical research contexts, radiolabeled Depreotide has been associated with the following effects:

1. Mild Injection Site Reactions – local erythema, itching, or swelling.

2. Gastrointestinal Effects – transient nausea or abdominal discomfort in animal and early human studies.

3. Allergic Reactions – rare hypersensitivity due to peptide structure.

4. Radiation-Associated Risks – dependent on the isotope (99mTc), not the peptide itself.

5. Renal Uptake – accumulation in kidneys may complicate imaging of nearby tumors.

Note for Research Use: These side effects are context-dependent, often related to radiolabeling and imaging conditions rather than the unlabeled peptide itself.

Disclaimer

This product is intended for laboratory research use only. Not for human use, medical treatment, or diagnostic application. Information provided is strictly for educational and experimental purposes.

Keywords

Depreotide, CAS 161982-62-3, 99mTc-depreotide, somatostatin analog, tumor imaging peptide, nuclear medicine research, radionuclide-drug precursor, SSTR imaging agent, cancer research peptide, peptide-based radiopharmaceutical.