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CN-122011087-A - Preparation method and application of self-assembled camptothecin-elastin-like peptide conjugate

CN122011087ACN 122011087 ACN122011087 ACN 122011087ACN-122011087-A

Abstract

The invention provides a preparation method and application of a self-assembled camptothecin-elastin-like peptide conjugate, belonging to the field of nano-drugs. The invention synthesizes the camptothecin self-assembled prodrug through the drug-linker conjugate, and the obtained camptothecin self-assembled prodrug can self-assemble in aqueous solution to form a one-dimensional nanotube structure through pi-pi interaction among camptothecin molecules. The invention adopts the design concept of self-assembled prodrug, uses camptothecin as a structural unit, obtains the hydrophilic-hydrophobic balanced camptothecin self-assembled prodrug by simply connecting hydrophilic polypeptides with different sequences, has high drug loading and improved solubility, can form a well-defined one-dimensional nano structure by simply dissolving in water, has excellent repeatability, shows a tumor inhibition effect obviously superior to clinical drug irinotecan in vivo anti-tumor treatment, can realize tumor growth inhibition of approximately 90 percent, has good biological safety, and has important significance for nano drug production preparation and clinical transformation.

Inventors

  • SU HAO
  • Wen Kaiying
  • ZHOU DONGDONG
  • XIE JING

Assignees

  • 四川大学

Dates

Publication Date
20260512
Application Date
20260203

Claims (10)

  1. 1. The camptothecin self-assembled prodrug is characterized by comprising a camptothecin pharmacophore, a neutral elastin peptide fragment and a cleavable linker coupling the two, wherein the structure of the camptothecin self-assembled prodrug is shown as a formula I: I is a kind of Wherein a, b are each independently selected from 0 or 1;R are each independently selected from amino acid residues of valine, alanine, glycine, asparagine, lysine or glutamic acid and n is selected from 1,2,3 or 4.
  2. 2. The self-assembled camptothecin prodrug of claim 1, wherein the structure of the self-assembled camptothecin prodrug is as shown in formula I-1, formula II-2, or formula III-3: Formula I-1 Formula II-2 Formula III-3 Wherein each R is independently selected from amino acid residues of valine, alanine, glycine, asparagine, lysine or glutamic acid, and n is selected from 1,2,3 or 4.
  3. 3. The self-assembled prodrug of camptothecin according to claim 1 or 2, wherein the structure of the self-assembled prodrug of camptothecin is selected from one of the following structures: 。
  4. 4. A method of preparing the self-assembled prodrug of camptothecin of any one of claims 1 to 3, comprising the steps of: (1) Swelling RINK AMIDE MBHA resin in an organic solvent, removing protective groups by using an alkali-containing deprotection solution, adding an activated glycine derivative for reaction, removing the protective groups of the glycine derivative by using the alkali-containing deprotection solution after the coupling reaction is finished, repeating the amide condensation process and the deprotection process, connecting amino acid derivatives to the resin one by one according to the designed polypeptide sequence, then cutting the polypeptide from the resin by using an acid-containing eluent, precipitating the polypeptide by using a poor solvent, centrifuging and discarding supernatant, drying the precipitate, and purifying by using a preparative high-performance liquid chromatography to obtain the neutral elastin peptide; (2) Reacting neutral elastin peptide with a drug-linker conjugate CPT-SS-Pyr to obtain the camptothecin self-assembled prodrug, wherein the CPT-SS-Pyr has the structure of 。
  5. 5. The method according to claim 4, wherein the ratio of the amounts of the neutral elastin peptide and CPT-SS-Pyr is 1:1-5, the solvent of the reaction is an organic solvent, the temperature of the reaction is 10-40 ℃ and the time is 4-24 hours.
  6. 6. The method of claim 4, wherein the preparation of the CPT-SS-Pyr comprises the steps of: (a) Reacting mercaptoethanol with 2,2' -dithiodipyridine to obtain Pyr-SS-OH; (b) And (3) reacting camptothecin, pyr-SS-OH, bis (trichloromethyl) carbonate and a catalyst to obtain CPT-SS-Pyr.
  7. 7. The method according to claim 6, wherein in the step (a), the ratio of the amount of the mercaptoethanol to the amount of the 2,2' -dithiodipyridine is 1:1-3, the solvent of the reaction is an alcohol solvent, the temperature of the reaction is 15-35 ℃ and the time is 1-5 hours; in the step (b), the mass ratio of the camptothecine to the bis (trichloromethyl) carbonate to the catalyst is 1:0.2-0.6:1-5, the solvent for the reaction is an organic solvent, the temperature for the reaction is 15-35 ℃ and the time is 2-8 hours.
  8. 8. The method according to claim 7, wherein in the step (a), the ratio of the amount of the mercaptoethanol to the amount of the 2,2' -dithiodipyridine is 1:2, the solvent of the reaction is methanol, the temperature of the reaction is 20-30 ℃ and the time is 3 hours; In the step (b), the mass ratio of the camptothecine to the bis (trichloromethyl) carbonate to the catalyst is 1:0.43:2.8, the solvent for the reaction is methylene dichloride, the temperature of the reaction is 20-30 ℃ and the time is 4-6 hours.
  9. 9. Use of a camptothecin self-assembled prodrug according to claim 1 or 2for the preparation of a medicament for the prevention and/or treatment of cancer.
  10. 10. The use according to claim 9, wherein the cancer is selected from the group consisting of gastric cancer, liver cancer, colon cancer and rectal cancer.

Description

Preparation method and application of self-assembled camptothecin-elastin-like peptide conjugate Technical Field The invention belongs to the field of nano-drugs, and in particular relates to a preparation method and application of a self-assembled camptothecin-elastin-like peptide conjugate. Background Cancer is a global health problem, and many new cases of cancer and high mortality place a great economic burden on various countries. Chemotherapy is the main means for treating cancers at present, hydrophobic small molecule drugs with molecular weights smaller than 1 KDa, represented by doxorubicin and taxol, are often used, and are administered by intravenous drip and other modes, so that proliferation and growth of tumor cells are directly inhibited, and further development of the cancers is controlled. The drug undergoes a series of biological barriers during vascular administration, and its physicochemical properties affect whether the drug can efficiently penetrate the barrier and achieve the desired therapeutic effect. Small molecule drugs are easy to be rapidly cleared by kidneys, the internal circulation time is short, the drug utilization rate is low, and the therapeutic effect is difficult to be expected. In addition, systemic toxicity due to low target specificity of small molecule drugs is a known cause of high incidence of adverse reactions and high mortality in cancer patients. There is therefore a need for more efficient and safe delivery means for chemotherapeutic agents to reduce side effects and to enhance therapeutic efficacy. Self-assembled prodrugs represent a novel class of drug delivery systems capable of self-assembling into well-defined nanostructures in aqueous solutions to achieve self-formulation and self-delivery, which are typically composed of hydrophobic pharmaceutically active ingredients (APIs) and hydrophilic precursor fragments. However, in conventional self-assembled prodrug systems, to enhance the solubility of hydrophobic drugs, hydrophilic components such as charged polypeptide sequences or oligoethylene glycol (OEG) are often required, and charges are easily bound to plasma proteins to affect the in vivo fate of the nanomedicine, whereas OEG has potential physiological toxicity. In particular, in the prior art, in order to hydrophilically modify Camptothecin (CPT) to enhance its water solubility and drug formation, polypeptides employed in camptothecin-polypeptide conjugates have been reported to be substantially charged (e.g., polylysine, polyglutamic acid, etc.). Such charged polypeptides, while improving water solubility, may present additional cytotoxicity, immunogenicity risks, and affect in vivo distribution and circulation time of the drug by non-specific binding to plasma proteins. Elastin-like peptide (ELP) is derived from natural protein, has good biocompatibility and water solubility, can be used as a hydrophilic fragment to be coupled with a small molecular drug to form a self-assembled prodrug, and is a drug delivery material with great potential. The current research on ELP as a drug delivery material mainly utilizes a biosynthesis method to synthesize high molecular weight ELP long peptide, has lower drug loading rate and is mostly limited to the formation of spherical prodrug particles driven by hydrophilic-hydrophobic interactions, and has less research on the assembly of ELP prodrugs driven by directional non-covalent acting forces between drugs. Disclosure of Invention The invention aims to solve the defects existing in the existing self-assembled prodrug system, in particular to overcome the problems of potential toxicity and in-vivo fate uncertainty caused by using charged polypeptides of the existing camptothecin-polypeptide conjugate, provides a preparation method and application of the self-assembled camptothecin-elastin-like peptide conjugate, and provides a new thought for designing nano prodrugs with high drug loading capacity and high biocompatibility. The core of the invention is that neutral (i.e. no net charge) elastin-like peptide (ELP) sequences are creatively adopted as hydrophilic fragments, and are coupled with Camptothecins (CPT) through a linker containing disulfide bonds, so as to construct a series of novel self-assembled prodrug molecules. The design abandons the traditional strategy of relying on charged polypeptide, utilizes excellent water solubility and biocompatibility of neutral ELP, ensures the self-assembly capability of prodrug molecules, fundamentally avoids the problems of toxicity risk, immunogenicity enhancement, non-specific combination of plasma proteins and the like caused by introducing charge fragments, and remarkably improves the biosafety of a nano prodrug system. The invention provides a camptothecin self-assembled prodrug which consists of a Camptothecin (CPT) pharmacophore, a neutral elastin peptide (ELP) fragment and a cleavable linker coupling the two, wherein the structure of the camptothecin self-as