We have developed a tumor environment-responsive polymeric anticancer prodrug containing pirarubicin (THP) conjugated to N-(2-hydroxypropyl) methacrylamide copolymer (PHPMA), [P-THP], through a spacer containing pH-sensitive hydrazone bond, that showed remarkable therapeutic effect against various tumor models and in a human pilot study. Toward clinical development, here we report THP release profile from its HPMA copolymer conjugate, the conjugate stability, protein and cell-binding and solubility of P-THP. Size exclusion chromatography of P-THP (molecular weight 38 kDa) showed similar hydrodynamic volume as bovine serum albumin (BSA) in aqueous solution, with no apparent interactions with BSA, nor aggregation by itself. pH-responsive release of free THP was reconfirmed at pHs 6.5 and lower. The drug release was significantly affected by a type of used buffer. Phosphate buffer seems to facilitate faster hydrazone bond cleavage at pH 7.4 whereas higher stability was achieved in L-arginine solution which yielded only little cleavage and THP release, approx. 15% within 2 weeks at the same pH at 25 °C. Furthermore, ex vivo study using sera of different animal species showed very high stability of P-THP. Incubation with blood showed high stability of P-THP during circulation, without binding to blood cells. These findings revealed that L-arginine solution provides appropriate media for formulation of P-THP infusion solution as tumor-targeted polymeric anticancer drug based on EPR effect.

• Klíčová slova
• Arginine, EPR effect, HPMA copolymer, Stability, Tumor environment responsive, Tumor-targeting,
• MeSH
• arginin chemie   MeSH
• doxorubicin analogy a deriváty   chemie   MeSH
• králíci MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• methakryláty chemie   MeSH
• myši MeSH
• nosiče léků chemie   MeSH
• pilotní projekty MeSH
• polymery chemie   MeSH
• protinádorové látky chemie   MeSH
• rozpustnost účinky léků   MeSH
• sérový albumin hovězí chemie   MeSH
• uvolňování léčiv účinky léků   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• arginin MeSH
• doxorubicin MeSH
• hydroxypropyl methacrylate MeSH Prohlížeč
• methakryláty MeSH
• nosiče léků MeSH
• pirarubicin MeSH Prohlížeč
• polymery MeSH
• protinádorové látky MeSH
• sérový albumin hovězí MeSH

Nanomedicine allows achievement of tumor-selective drug delivery because of the enhanced permeability and retention (EPR) effect of solid tumors. We report here the first clinical application of a new agent-HPMA copolymer-conjugated pirarubicin (P-THP)-with a molecular size of about 8 nm, or 38.5 kDa. A patient had advanced prostate cancer with multiple metastases in the lung, pelvis, femur, and perhaps the sacrum. In April 2013, this 60-year-old patient started treatment with leuprorelin and estradiol, which continued until July 2014, but the patient became refractory to this treatment. So the patient underwent proton beam radiotherapy targeted to the primary prostate cancer, and P-THP was administered for numerous metastatic tumor nodules concomitantly with radiotherapy. This combination therapy had remarkable results, with complete remission of multiple metastases in the lung and bone. The prostate-specific antigen (PSA) value was decreased from about 1000 ng/mL on April 30, 2013, to about 100 ng/mL on June 24, 2013, with hormone therapy, but rose again to 964.2 ng/mL and then to 1472 ng/mL in July 2013, during leuprorelin administration. P-THP treatment administered concomitantly with proton beam irradiation was started in August 2013. The PSA value was decreased to 102 ng/mL on August 26, 2013, and then to 0.971 ng/mL on October 8, 2013, and 0.277 ng/mL on January 15, 2015. The P-THP doses ranged from 30 to 75 mg of free THP equivalent/patient every 2-3 weeks without signs of serious toxicity, such as cardiovascular side effects or a reduction in quality of life. No evidence of relapse was found more than 20 months after P-THP administration. This case demonstrates the value of hydrazone-bonded polymeric drugs in multimodal therapy.

• MeSH
• doxorubicin analogy a deriváty   terapeutické užití   MeSH
• kombinovaná terapie MeSH
• lékové transportní systémy * MeSH
• lidé středního věku MeSH
• lidé MeSH
• methakryláty chemie   MeSH
• nádory kostí sekundární   terapie   MeSH
• nádory plic sekundární   terapie   MeSH
• nádory prostaty patologie   terapie   MeSH
• prognóza MeSH
• protinádorové látky terapeutické užití   MeSH
• staging nádorů MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH
• Názvy látek
• doxorubicin MeSH
• hydroxypropyl methacrylate MeSH Prohlížeč
• methakryláty MeSH
• pirarubicin MeSH Prohlížeč
• protinádorové látky MeSH

Previously we showed that linear poly(N-(2-hydroxypropyl)methacrylamide) conjugates of pirarubicin (THP), LP-THP, with MW about 39 kDa, exhibited far better tumor accumulation and therapeutic effect than that of parental free THP. To improve the pharmacokinetics of LP-THP further, high-MW conjugate of poly(amido amine) (PAMAM) dendrimer grafted with semitelechelic HPMA copolymer (PHPMA) was synthesized [star polymer (SP); 400 kDa] and conjugated with THP via hydrazone bond-containing spacer (SP-THP). THP was conjugated to SP to form SP-THP via acid cleavable hydrazone bonding, which responds to acidic milieu of tumor tissue. As a consequence, it would release free THP, by active therapeutic principle. SP-THP exhibits larger hydrodynamic diameter (25.9 nm) in aqueous solution than that of LP-THP (8.2 nm) as observed by light scattering and size exclusion chromatography. Because of the larger size, the tumor AUC5h-72 h of SP-THP was 3.3 times higher than that of LP-THP. More importantly, released free THP was retained selectively in the tumor tissue for at least up to 72 h after administration of SP-THP. We found that SP-THP exhibited superior antitumor effect to LP-THP against both S-180 tumor-bearing mice in vivo, and with chemically AOM/DSS-induced colon tumor-bearing mice, most probably due to their different molecular size. In our comparison study of in vitro and in vivo behavior of SP-THP and LP-THP we concluded that SP-THP exhibited enhanced therapeutic efficacy not only in implanted tumor but also in orthotopic/spontaneous tumor despite its higher toxicity compared to LP-THP. Upon these findings further investigation using various tumors including transgenic, and metastatic tumors is going to be conducted soon.

• Klíčová slova
• Acid-cleavable linkage, Chemical carcinogenesis, Controlled drug release, Dendrimer-derived polymer conjugate, EPR effect, HPMA polymer conjugate, Pirarubicin (THP),
• MeSH
• berberinové alkaloidy chemie   farmakokinetika   MeSH
• dendrimery chemie   farmakokinetika   MeSH
• doxorubicin analogy a deriváty   chemie   farmakokinetika   farmakologie   MeSH
• HeLa buňky MeSH
• lidé MeSH
• melanom experimentální MeSH
• methakryláty chemie   farmakokinetika   MeSH
• myši inbrední ICR MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory farmakoterapie   MeSH
• nosiče léků chemie   farmakokinetika   MeSH
• polymery chemie   farmakokinetika   MeSH
• protinádorové látky chemie   farmakokinetika   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 2,3,10,11-tetrahydroxytetrahydroprotoberberine MeSH Prohlížeč
• berberinové alkaloidy MeSH
• dendrimery MeSH
• doxorubicin MeSH
• hydroxypropyl methacrylate MeSH Prohlížeč
• methakryláty MeSH
• nosiče léků MeSH
• PAMAM Starburst MeSH Prohlížeč
• pirarubicin MeSH Prohlížeč
• polymery MeSH
• protinádorové látky MeSH