Tirazone (tirapazamine)

To reduce the off-target effects in nontumor cells and better control safety risks, a TME-triggered cascade-activation nanodiagnostic and therapeutic platform (AA@Cas-H@HTS) is designed, which achieves the hypoxia activation of prodrug tirapazamine (TPZ) and spatiotemporal release of CRISPR/Cas9 ribonucleoprotein...Importantly, targeting HIF-1α disrupts the programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) signaling pathway, which effectively reshapes the immune-suppressive TME and activates T cell-mediated antitumor immunity. Taken together, we have provided a TME-triggered cascade-activation nanoplatform to alleviate hypoxia for improved cancer immunotherapy.

Meanwhile, the released HIF-1α siRNA interfered with the up-regulated HIF-1α induced by the deepened hypoxia condition, which caused hypoxia tolerance in tumors, reduced its expression activity, and achieved synergistic killing of tumor cells with chemotherapy. This work provides an effective multimodal synergistic therapy strategy to promote tumor therapeutic index, which may possess a promising future in clinical application.

5-ALA-PDT combined with TPZ can inhibit cell proliferation, increase apoptosis, and inhibit the PI3K/Akt/mTOR pathway, thus inhibiting tumor growth and metastasis and improving anti-cancer effects.

Herein, we developed a novel TACE system by inducing bovine serum albumin (BSA) loaded hypoxia-activated prodrug (tirapazamine, TPZ) nanoparticle (BSATPZ) for sustained drug release...The effects could be partially mediated by the rebuilt immune responses, as BSATPZ nanoparticle can served as an immunogenic cell death (ICD) inducer. Collectively, our results suggest that BSATPZ nanoparticle-based TACE therapy could be a promising strategy to improve clinical outcomes for patients with HCC and provide a preclinical rationale for evaluating TPZ therapy in clinical studies.

The drug candidate was also tested for its in-vivo chemopreventive efficacy against DMBA-induced mammary gland cancer alone and in combination with Tirapazamine (TPZ)...Serum metabolomics conducted with 1H NMR confirmed that BBAP-6 prevented HIF-1α and NF-κB-induced metabolic changes in DMBA mammary gland cancer model. In a nutshell, it can be concluded that BBAP-6 activates PHD-2 and exhibits anticancer potential.

A multifunctional cascade bioreactor based on the H2S-responsive mesoporous Cu2Cl(OH)3-loaded hypoxic prodrug tirapazamine (TPZ), in which the outer layer was coated with hyaluronic acid (HA) to form TPZ@Cu2Cl(OH)3-HA (TCuH) nanoparticles (NPs), demonstrated a synergistic antitumor effect through combining the H2S-driven cuproptosis and mild photothermal therapy...The enriched Cu2+ induced not only cuproptosis by promoting lipoacylated dihydrolipoamide S-acetyltransferase (DLAT) heteromerization but also performed chemodynamic therapy though catalyzing H2O2 to produce highly toxic hydroxyl radicals ·OH. Therefore, the nanoparticles TCuH offer a versatile platform to exert copper-related synergistic antitumor therapy.

Carmine staining, histopathology, and scanning electron microscopy demonstrated that BBAP-7, alone or with tirapazamine, restored mammary gland surface morphology and structural integrity. Additionally, BBAP-7 therapy significantly reduced oxidative stress and glycolysis. The findings reveal that BBAP-7 activates PHD-2, making it a promising anticancer drug.

Herein, we developed a strategy using the combination of PDT and hypoxia-activated bioreductive drug tirapazamine (TPZ)...With laser irradiation, overexpressions of PDT tolerance factors NQO1 and HIF-1α were inhibited by this PDT process. The synergistic effect of PDT and TPZ significantly improved the performance of DPTC-MNs in the treatment of melanoma and cutaneous squamous cell carcinoma and has good biocompatibility.

In HNC MCTSs, hypoxic cytotoxicity ratios for the hypoxia activated prodrugs (HAP) evofosfamide and tirapazamine were much smaller than have been reported for uniformly hypoxic 2D monolayers in gas chambers, and many viable cells remained after HAP exposure. Cells in solid tumors and MCTSs experience three distinct O microenvironments dictated by their distances from blood vessels or MCTS surfaces, respectively; oxic, hypoxic, or intermediate levels of hypoxia. These studies support the application of more physiologically relevant in vitro 3D models that recapitulate the heterogeneous microenvironments of solid tumors for preclinical cancer drug discovery.

P2, N=110, Recruiting, Teclison Ltd. | Trial completion date: Dec 2024 --> Dec 2025 | Trial primary completion date: Oct 2024 --> Oct 2025

To solve this problem, we constructed polydopamine (PDA)-cloaked Fe-based metal organic frameworks (MOFs) loaded with d-arginine (d-Arg), glucose oxidase (GOX), and the chemotherapeutic drug tirapazamine (TPZ)...The combined administration of low doses of X-ray irradiation and nanoparticles reduces the side effects on healthy tissue and can prevent lung metastases in mice. This work highlights the synergistic treatment of osteosarcoma via ST/GT/CDT/RT/MRI/ chemotherapy using a PDA-cloaked MOF system.

As a proof of concept, a bioengineered fusion protein containing a dendritic mesoporous silicon (DMSN)-binding peptide, and a tumor-targeted and acidity-decomposable ferritin heavy chain 1 (FTH1), was constructed by fusion expression and further assembled on the surface of DMSN companying with the insertion of hypoxia-activated prodrug tirapazamine (TPZ) and glucose oxidase (GOX) to establish a nanoreactor for precise starvation/chemosynergistic tumor therapy...More significantly, the presence of "molecular glue" elevated the tumor-targeting capacity of nanoreactors and further enhanced the starvation/chemosynergistic therapeutic effect remarkably, suggesting that such a strategy provided a solution for the functionality of nanomaterials and facilitated the design of novel targeting nanomedicines. Overall, this study highlights materials-binding peptides as a new type of "molecular glue" and opens new avenues for designing and exploring active biological materials for biological functions and applications.

To simultaneously tackle these pivotal problems, we herein create an albumin-based nanoplatform co-delivering IR780, NLG919 dimer and a hypoxia-activated prodrug tirapazamine (TPZ) as the dual enhancer for synergistic cancer therapy. Eventually, enriched intratumoral GSH triggers the activation of NLG919 to mitigate the immunosuppressive TME via specific indoleamine 2,3-dioxygenase 1 (IDO-1) inhibition, consequently promoting the intratumoral infiltration of CTLs and the killing of both primary and distant tumors, while the resultant memory T cells allows nearly 100% suppression of tumor recurrence and metastasis. This nanoplatform sets up an example for dully enhanced photodynamic immunotherapy of breast cancer via hypoxia-activated chemotherapy, and paves a solid way for the treatment of other hypoxic and immunosuppressive malignant tumors.

The importance of functional gap junctions is indicated as a mechanism to promote the therapeutic effect. Collectively, the data support a novel therapeutic combination to treat melanoma and the development of a medical device to deliver the treatment in situ.

Following the GOx-induced amplification of hypoxia, tirapazamine (TPZ) was transformed into the highly toxic benzotriazinyl radical (BTZ·), exhibiting enhanced antitumor activity...Herein, a bioresponsive diselenide-functionalized dextran-based hydrogel with GPx-like catalytic activity was developed for GSH consumption-enhanced local starvation- and hypoxia-activated melanoma therapy. Results showed that the overproduced HO led to accelerated intracellular GSH consumption under the cascade catalysis of small molecular selenides released from the degraded hydrogel, further enhancing the curative effect of in situ HO and subsequent multimodal cancer treatment.

Early studies targeting hypoxia show promising results; however, further research is needed to understand the effects of HAPs in combination with embolization in the treatment of HCC. This review aims to summarize current knowledge on the role of hypoxia and HIF-1α in HCC, as well as the potential of HAPs and liver-directed embolization.

The fabricated porous MS were introduced intrahepatically and designed to release a combination therapy of Doxorubicin (DOX) and Tirapazamine (TPZ), which is a hypoxia-activated prodrug. Porous DOX-TPZ MS were very effective in suppressing tumor growth in rats, and induction tissue necrosis was associated with high intra-tumor drug concentrations. Porous particles without drugs showed some advantages over non-porous particles, suggesting that morphology may affect the treatment outcomes.

We describe methods for preparing and characterizing TPZ-loaded CalliSpheres microspheres (CSMTPZs) with regard to their properties as a chemoembolization agent, which includes 1) preparation of CSMTPZs and determination of drug loading level, 2) in vitro determination of TPZ release, 3) assessment of CSMTPZ size and appearance, and 4) determination of TPZ pharmacokinetics and intratumoral drug concentration in vivo. These methods can be adapted for further clinical I trial.•This is to our knowledge the first methods for preparing and characterizing tirapazamine-loaded microspheres with regard to their properties as a chemoembolization agent•Detailed protocols for preparation of CSMTPZs, determination of drug loading level, in vitro determination of TPZ release, assessment of CSMTPZ size and appearance, and in vivo determination of TPZ pharmacokinetics and intratumoral drug concentration•Adaptable to experiments on other animal models and clinical trials.

These data support the fact that the main mechanism of action of TPZ under aerobic conditions is oxidative stress. The unchanged expression of intranuclear antioxidant proteins peroxiredoxin, glutaredoxin, and glutathione peroxidase, and a modest increase in the expression of DNA damage repair proteins, tend to support non-site-specific but not intranuclear oxidative stress as a main factor of TPZ aerobic cytotoxicity.

This nanoscale UiO-67 MOF platform can further our understanding of CO functions while produce CO in a controllable manner during cancer therapeutic administration.

Here, glucose oxidase (GOX) and hypoxia-activated prodrug tirapazamine (TPZ) are loaded into photothermal conversion agent polydopamine (PDA) as the glucose/oxygen-exhausting nanoreactor named PGT...Mechanically, it is revealed that the nanoreactor significantly increases hypoxia level and downregulates the expression of hypoxia-inhibitory factor-1α (HIF-1α), thereby promoting T cell activation and macrophage polarization to remodel tumor immunosuppressive microenvironment. Therefore, this tumor microenvironment-regulable nanoreactor with sustainable and cascade targeted starvation-chemotherapy provides a novel insight into the treatment of hypoxic tumor.

We revealed the improved synergistic anti-tumor effects of CSMTPZ therapy in the rabbit VX2 liver cancer model. Our data support the clinical evaluation of CSMTPZs in the treatment of hepatocellular carcinoma, and CSMTPZ administration might serve as a successful therapeutic strategy for this malignancy.

P2, N=110, Recruiting, Teclison Ltd. | N=60 --> 110 | Trial completion date: Dec 2023 --> Dec 2024 | Trial primary completion date: Sep 2023 --> Oct 2024

Potential models were used for interaction studies with hypoxia-specific molecules (tirapazamine, apaziquone, and ENMD) using docking analysis. It also elucidates that the therapeutic effect is altered concerning population-dependent genetic changes in the individual. The study, therefore, asserts the need to set up a personalized drug design approach to enhance tumor hypoxia treatment efficacy.

In HNC MCTSs, hypoxic cytotoxicity ratios for the hypoxia activated prodrugs (HAP) evofosfamide and tirapazamine were much smaller than have been reported for uniformly hypoxic 2D monolayers in gas chambers, and many viable cells remained after HAP exposure. Cells in solid tumors and MCTSs experience three distinct O microenvironments dictated by their distances from blood vessels or MCTS surfaces, respectively; oxic, hypoxic, or intermediate levels of hypoxia. These studies support the application of more physiologically relevant in vitro 3D models that recapitulate the heterogeneous microenvironments of solid tumors for preclinical cancer drug discovery.

By using TPZ and PFA and the enhanced permeability and retention effect of nanoparticles, TPZ/PFA@UiO-66@PDA can target tumor tissues, enhance hypoxia in the tumor microenvironment, and activate TPZ. Combined with PTT, the growth of osteosarcoma xenografts can be effectively inhibited.

Using histopathology, we investigated response to combined radiotherapy (RT) and hypoxic prodrug Tirapazamine (TPZ) on our jumbo spheroids produced using two sarcoma cell lines (STS117 and SK-LMS-1). Our results demonstrate that TPZ preferentially targets the hypoxic core (STS117: p = 0.0009; SK-LMS-1: p = 0.0038), but the spheroids' hypoxic core harbored as much DNA damage 24 h after irradiation as normoxic spheroid cells. These results validate our microfluidic device and jumbo spheroids as potent fundamental and pre-clinical tools for the study of hypoxia and its effects on treatment response.

P2, N=60, Recruiting, Teclison Ltd. | Not yet recruiting --> Recruiting

The intracellular observation of nanogel indicated that the HA-C60/TPENH2 nanogel was self-fluorescence for cell imaging. This study applied PDT-BRT to design smart HA-based nanogel with targeted delivery, pH response, and AIEgen feature for efficient cancer therapy.

SLC7A11 overexpression could restored the proliferation and migration abilities inhibited by TPZ. Thus, we for the first time demonstrated that TPZ could inhibit the proliferation and migration of osteosarcoma cells, and induce ferroptosis in part through inhibiting SLC7A11.

To determine the contribution of hypoxia to PARPi resistance in tumors, we used the hypoxic cytotoxin tirapazamine to selectively kill hypoxic tumor cells. We found that the selective elimination of hypoxic tumor cells led to a substantial antitumor response when used with PARPi compared with that in tumors treated with PARPi alone, without enhancing normal tissue toxicity. Since human breast cancers with BRAC1/2 mutations have an increased hypoxia signature and hypoxia reduces the efficacy of PARPi, then eliminating hypoxic tumor cells should enhance the efficacy of PARPi therapy.

Furthermore, the cancer treatment effects of HIF-1α inhibitors (tirapazamine, SYP-5, and IDF-11774) were evaluated using the platform. The treatment effect of SYP-5 was enhanced under the hypoxic conditions with fewer side effects, similar to the findings of TPZ. We can envision its wide application in future investigations of cancer metastasis and screening of drugs under hypoxic conditions with the potential to replace animal experiments.

Herein, a tumor microenvironment triggered cascade-activation nanoplatform (A-NP ) is prepared based on β-lapachone (β-Lap) and tirapazamine (TPZ) for the synergistic therapy of HCC...The studies in vitro and in vivo consistently demonstrate that the as-prepared A-NP nanoplatform possesses an excellent synergistic anti-tumor effect. This design of nanoplatform with cascade activation effect provides a promising strategy for HCC treatment.

P2, N=60, Not yet recruiting, Teclison Ltd.

P2a, N=80, Recruiting, Teclison Ltd. | Active, not recruiting --> Recruiting | Trial completion date: Dec 2021 --> Dec 2022 | Trial primary completion date: Oct 2020 --> Dec 2021

Decreased DNA content was observed in the internal stacks as compared to the external stacks when treated with tirapazamine, which suggests the internal scaffold stacks had higher levels of hypoxia than the external scaffolds. This stacked silk scaffold system presents a method for creating a single culture model capable of generating controllable cell-driven microenvironments through different stacks that can be individually assessed and used for drug screening.

All synthesized 6(7)-aminoquinoxaline-2-carbonitrile 1,4-dioxides 3-6 demonstrated higher cytotoxicity and hypoxia selectivity compared to the reference agent tirapazamine against breast adenocarcinoma cell lines (MCF7, MDA-MB-231)...Of the 32 novel synthesized derivatives, approximately 20 of the 6(7)-amino-3-phenylquinoxaline-2-carbonitrile 1,4-dioxides demonstrated high antiproliferative potency against wild type leukemia cells K562 and drug-resistant subline K562/4 with the expression of p-glycoprotein (p-gp) compared to the reference agent doxorubicin, which exhibited one order of magnitude lower activity towards K562/4 cells than towards K562 cells...Thus, the described series of quinoxaline 1,4-dioxides has high anticancer potential and good aqueous solubility. Therefore, these compounds are promising for further drug development of hypoxia-targeted anticancer agents.

Taken these results, HO-MeOH-E has the potential effect in hypoxia-activated chemotherapy specifically on breast cancer stem-like cells with CD44CD24 phenotype.