5-Fluorouracil Rechallenge After Cardiotoxicity

Capecitabine-induced-coronary-vasospasm leading to polymorphic ventricular tachycardia and cardiac arrest

Capecitabine, a pro-drug of 5-fluorouracil, is commonly used in the treatment of breast and colorectal cancer. Its side effects, including nausea, vomiting, diarrhea, fatigue, loss of appetite, and bone marrow suppression, are well recognized. However, coronary vasospasm represents a less commonly recognized but significant complication of fluoropyrimidine-based therapies such as capecitabine. Proposed mechanisms for this adverse effect complication include direct endothelium-independent vasoconstriction, activation of protein kinase C, and activation of the cyclooxygenase pathway. In this report, we present a case of capecitabine-induced coronary vasospasm leading to progressive, focal ST-elevations, myocardial ischemia, and subsequently polymorphic ventricular tachycardia. These events were captured on telemetry, in a male in his early 40s, diagnosed with stage IIIB sigmoid colon cancer. Notably, the patient had no pre-existing coronary artery disease or other cardiovascular risk factors. Upon diagnosis, the patient was initiated on a calcium channel blocker, verapamil, to mitigate further coronary vasospasm events. After thorough discussions that prioritized the patient's input and values, an implantable cardioverter-defibrillator was placed subcutaneously. Following discharge, the patient restarted capecitabine therapy along with verapamil prophylaxis and did not experience any subsequent shocks from his ICD as assessed during his outpatient follow-up visits. This case emphasizes the need to involve patients in decision-making processes, especially when managing unexpected and serious complications, to ensure treatments align with their quality of life and personal preferences.

A Rare Cause and Management of Ventricular Fibrillation: 5-Fluorouracil Toxicity

Um homem de 65 anos com histórico de carcinoma de língua procurou o pronto-socorro com contrações insensíveis estando em casa. Ele estava em terapia com 5-fluorouracil (5-FU) na época. O paciente foi desfibrilado e intubado porque a fibrilação ventricular (FV) se desenvolveu durante o monitoramento no pronto-socorro. A ecocardiografia mostrou que a fração de ejeção do ventrículo esquerdo (FEVE) era de 70% e a espessura do septo interventricular era de 15 mm. A angiografia coronária não revelou qualquer estenose crítica. A ressonância magnética cardíaca (RMC) não mostrou anormalidade de perfusão, fibrose ou cicatriz sugestiva de envolvimento cardíaco. Foi sugerido que a arritmia do paciente estava relacionada principalmente à cardiotoxicidade induzida pelo 5-FU.

O fato de as causas secundárias terem sido proeminentes em nosso caso, de nenhuma patologia cardíaca óbvia que pudesse causar arritmia ter sido encontrada no exame detalhado e de a arritmia não ter recorrido durante a internação hospitalar, que durou até 15 dias, nos levou a acreditar que esse paciente poderia receber alta sem um cardioversor-desfibrilador implantável. Nosso caso foi apresentado para contribuir com a literatura.

Molecular mechanism of empagliflozin cardioprotection in 5-fluorouracil (5-FU)-induced cardiotoxicity via modulation of SGLT2 and TNFα/TLR/NF-κB signaling pathway in rats

One of the commoly used chemotherapeutic agents is 5-Fluorouracil (5-FU). Unfortunately, the clinical administration of 5-FU is complicated with serious cardiotoxic effects and the safe use becomes an urgent task in cardio-oncology. Till now, there are no studies discussed the role of empagliflozin (EMP) against 5-FU cardiotoxicity. Thus, we investigated this effect and the involved mechanisms in 5-FU induced heart injury. Forty male rats of Wistar albino species were used and divided randomly into four groups. Group I is the control group, group II is EMP given group, group III is 5-FU cardiotoxic group and group IV is 5-FU plus EMP group. 5-FU (150 mg/kg) was administered as a single intraperitoneal (i.p.) dose on 1st day to induce cardiotoxicity with or without EMP (30 mg/kg/d) orally for 5 days. The dose of 5-FU is relevant to the human toxic dose. Our data showed that 5-FU given group caused cardiotoxicity with significant increase of serum cardiac enzymes, toll like receptors, enhancement of nuclear factor kappa B (NF-κB), interleukin1β (IL1β), IL6, myeloid-differentiation-factor 88 (MYD88), heart weight, malondialdehyde (MDA), tumor-necrosis-factor-alpha (TNFα), sodium glucose co-transporter 2 (SGLT2), P53 and caspase3 expression with clear histopathological features of cardiotoxicity. Moreover, there is a significant decrease in reduced glutathione (GSH) and total antioxidant capacity (TAC). Interestingly, co-administration of EMP could ameliorate 5-FU induced biochemical and histopathological changes. This effect may be due to modulation of SGLT2, decreasing inflammation, oxidative stress and apoptosis with downregulation of an essential inflammatory cascade that mediates 5-FU cardiotoxicity; TNFα/TLR/NF-κB.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43188-023-00204-1.

Invasive Evaluation for Coronary Vasospasm

Vasospastic angina (VSA) occurs at rest and on exertion, with transient electrocardiographic ischemic changes. VSA presents with spontaneous coronary artery spasm (CAS); it has been associated with stable angina, acute coronary syndromes, and sudden cardiac death. CAS can be identified in normal arteries or non-obstructive coronary atherosclerosis, but is also prevalent in patients with coronary artery disease. The diagnosis is made with invasive coronary reactivity testing with provocation using acetylcholine (Ach). Epicardial spasms can be visualized through coronary angiography as a reversible epicardial vessel narrowing, while the diagnosis of microvascular spasm can be made when angina symptoms and ECG changes happen following intracoronary Ach without epicardial spasm. Identification of CAS allows for risk stratification and specific therapies targeting endothelial dysfunction and paradoxical vascular smooth muscle cell constriction. Therapies include calcium channel blockers as monotherapy or in a combination of a dihydropyridine and non-dihydropyridine. Short-acting nitrates offer acute symptomatic relief but long-acting nitrates should be used sparingly. This current update on invasive evaluation of VSA discusses unified Ach protocols.

6-Regioisomeric 5,8-quinolinediones as potent CDC25 inhibitors against colorectal cancers

Precise and accurate control of cell cycle progression is required to maintain cell identity and proliferation. Failing to keep it will lead to genome instability and tumorigenesis. Cell Division Cycle 25 (CDC25) phosphatases are the key to regulating the activity of the master cell cycle controller, cyclin-dependent kinases (CDKs). Dysregulation of CDC25 has been shown to associate with several human malignancies. Here, we reported a series of derivatives of the CDC25 inhibitor, NSC663284, bearing quinones as core scaffolds and morpholin alkylamino side chains. Among these derivatives, the cytotoxic activity of the 6-isomer of 5,8-quinolinedione derivatives (6b, 16b, 17b, and 18b) displayed higher potency against colorectal cancer (CRC) cells. Compound 6b possessed the most antiproliferative activity, with IC₅₀ values of 0.59 μM (DLD1) and 0.44 μM (HCT116). The treatment of compound 6b resulted in a remarkable effect on cell cycle progression, blocking S-phase progression in DLD1 cells straight away while slowing S-phase progression and accumulated cells in the G₂/M phase in HCT116 cells. Furthermore, we showed that compound 6b inhibited CDK1 dephosphorylation and H4K20 methylation in cells. The treatment with compound 6b induced DNA damage and triggered apoptosis. Our study identifies compound 6b as a potent CDC25 inhibitor that induces genome instability and kills cancer cells through an apoptotic pathway, deserving further investigation to fulfill its candidacy as an anti-CRC agent.

Coronary atherosclerosis and chemotherapy: From bench to bedside

Cardiovascular disease, particularly coronary artery disease, is the leading cause of death in humans worldwide. Coronary heart disease caused by chemotherapy affects the prognosis and survival of patients with tumors. The most effective chemotherapeutic drugs for cancer include proteasome inhibitors, tyrosine kinase inhibitors, immune checkpoint inhibitors, 5-fluorouracil, and anthracyclines. Animal models and clinical trials have consistently shown that chemotherapy is closely associated with coronary events and can cause serious adverse cardiovascular events. Adverse cardiovascular events after chemotherapy can affect the clinical outcome, treatment, and prognosis of patients with tumors. In recent years, with the development of new chemotherapeutic drugs, new discoveries have been made about the effects of drugs used for chemotherapy on cardiovascular disease and its related mechanisms, such as inflammation. This review article summarizes the effects of chemotherapeutic drugs on coronary artery disease and its related mechanisms to guide efforts in reducing cardiovascular adverse events during tumor chemotherapy, preventing the development of coronary heart disease, and designing new prevention and treatment strategies for cardiotoxicity caused by clinical tumor chemotherapy.

Managing life-threatening 5-fluorouracil cardiotoxicity

5-Fluorouracil (5-FU), a known cardiotoxin, is the backbone for the treatment of colorectal cancer. It is associated with arrhythmias, myocardial infarction and sudden cardiac death. Most commonly, it is associated with coronary vasospasm secondary to direct toxic effects on vascular endothelium.A woman with metastatic colon cancer, originally treated with a 5-FU infusion as part of the FOLFIRI (Folinic acid, 5-Fluorouracil, Irinotecan) regimen, was unable to tolerate the chemotherapy due to chest pain. She was transitioned from infusional 5-FU to inferior 1-hour bolus 5-FU, in an attempt to minimise cardiotoxicity, but had disease progression. A multidisciplinary decision was made to again trial 5-FU infusion and pretreat with diltiazem. She tolerated chemotherapy without adverse events. A multidisciplinary discussion is recommended for co-management of reversible 5-FU-associated cardiotoxicity. After coronary artery disease (CAD) risk stratification and treatment, empiric treatment with calcium channel blockers and/or nitrates may allow patients with suspected coronary vasospasm, from 5-FU, to continue this vital chemotherapy.

Permissive Cardiotoxicity

The field of cardio-oncology was born from the necessity for recognition and management of cardiovascular diseases among patients with cancer. This need for this specialty continues to grow as patients with cancer live longer as a result of lifesaving targeted and immunologic cancer therapies beyond the usual chemotherapy and/or radiation therapy. Often, potentially cardiotoxic anticancer treatment is necessary in patients with baseline cardiovascular disease. Moreover, patients may need to continue therapy in the setting of incident cancer therapy–associated cardiotoxicity. Herein, we present and discuss the concept of permissive cardiotoxicity as a novel term that represents an essential concept in the field of cardio-oncology and among practicing cardio-oncology specialists. It emphasizes a proactive rather than reactive approach to continuation of lifesaving cancer therapies in order to achieve the best oncologic outcome while mitigating associated and potentially off-target cardiotoxicities.

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Permissive cardiotoxicity is a terminology that represents a vital concept in cardio-oncology

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It emphasizes continued cancer therapy if appropriate, while mitigating cardiotoxicities.

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Its application is guided by understanding the cancer treatment, alternatives, and prognosis.

Cardioprotective effects of bosentan in 5-fluorouracil-induced cardiotoxicity

5-fluorouracil (5-FU) is a widely used chemotherapeutic agent but cardiotoxicity challenges its clinical usefulness. Thus, searching for more cardioprotective drugs is highly required to prevent the accompanied cardiac hazards. Up to date, the different mechanisms involved in 5-FU cardiotoxicity are still unclear and there is no evaluation of bosentan's role in controlling these cardiac complications. This forced us to deeply study and evaluate the possible cardiopreserving properties of bosentan and different mechanisms involved in mediating it. 32 Wistar albino rats were included in our experiment and induction of cardiotoxicity was performed via administration of 5-FU (150 mg/kg) on 5th day of the experiment by intraperitoneal (i.p.) injection with or without co-administration of bosentan (50 mg/kg/day) orally for 7days. Our data revealed that 5-FU could induce cardiotoxicity which was detected as significant increases of troponin I, lactate dehydrogenase (LDH), creatine kinase- MB (CK-MB), endothelin receptors, malondialdehyde (MDA), toll like receptor4 (TLR4), myeloid differentiation primary response 88 (MyD88), nuclear factor kappa B (NFκB), and caspase 3 levels. However, there is marked decrease in endothelial nitric oxide synthase (eNOS), reduced glutathione (GSH) and total antioxidant capacity (TAC). In addition, the histopathological examination showed severe toxic features of cardiac injury. Interestingly, co-administration of bosentan could ameliorate 5-FU-induced cardiotoxicity via improving the detected biochemical and histopathological changes besides modulation of TLR4/MyD88/NFκB signaling pathway, eNOS, and endothelin receptors. Bosentan had a significant cardioprotective effect against 5-FU induced cardiac damage. This effect may be attributed to its ability to inhibit endothelin receptors, stimulates eNOS, anti-oxidant, anti-inflammatory, anti-apoptotic properties with modulation of TLR4/MyD88/NFκB signaling pathway.

The IL-6/STAT Signaling Pathway and PPARα Are Involved in Mediating the Dose-Dependent Cardioprotective Effects of Fenofibrate in 5-Fluorouracil-Induced Cardiotoxicity

PURPOSE

The cardiotoxicity of anticancer drugs such as 5-fluorouracil (5FU) is a major complication that challenges their clinical usefulness. Thus there is a critical need to find new protective drugs to defend against these harmful side effects. Up to now, there have been no studies evaluating the possible cardioprotective effects of fenofibrate (FEN) in 5FU-induced cardiotoxicity. Therefore, we aimed in the current model to evaluate such an effect of FEN and to explore different mechanisms mediating it.

METHODS

We used FEN (25, 50, 100 mg/kg/day) administered orally for 7 days with induction of cardiotoxicity by intraperitoneal (i.p.) injection of 5FU (150 mg/kg) on the fifth day.

RESULTS

The current study showed that 5FU succeeded in inducing cardiotoxicity, manifested by significantly elevated levels of cardiac enzymes, tissue malondialdehyde (MDA), interleukin 6 (IL-6), signal transducer and activator of transcription 4 (STAT4), and caspase-3. Furthermore, the 5FU group showed toxic histopathological changes including marked cardiac damage and a significant decrease in reduced glutathione (GSH), total antioxidant capacity (TAC), and peroxisome proliferator-activated receptor alpha (PPARα) expression. FEN reversed 5FU-induced cardiotoxicity by various mechanisms including upregulation of PPARα, inhibition of the IL-6/STAT signaling pathway, and anti-inflammatory, antiapoptotic, and antioxidant properties.

CONCLUSION

FEN demonstrated a significant cardioprotective effect against 5FU-induced cardiac damage.

Preparation, characterization and in vitro anticancer performance of nanoconjugate based on carbon quantum dots and 5-Fluorouracil

This study is focused on the development of a nanodevice for loading and release of 5-Fluorouracil (5-FU) with a view to improving its therapeutic efficiency, using as strategy the fabrication of a nanoconjugate through drug anchorage on the surface of carbon quantum dots (CQD). Several physicochemical and analytical techniques were employed to obtain information about materials morphology, structure, and optical properties. The results indicated that the interactions between both entities resulted in good physicochemical properties and photostability. Acid pH favored drug release, indicating a tendency to release 5-FU from 5-FU-CQD into the tumor microenvironment. The cytotoxicity of CQD and 5-FU-CQD nanoconjugate was evaluated against normal human lung fibroblast (GM07492A) and human breast cancer (MCF-7) cell lines. The CQD was non-toxic, indicating that these materials are biocompatible and can be used as a nanocarrier for 5-FU in biological systems. For the 5-FU-CQD nanoconjugate, it was observed a reduction in toxicity for normal cells compared to free 5-FU, suggesting that drug anchoring in CQD reduced drug-associated toxicity, while for cancer cells exhibited an antitumor effect equivalent to that of the free drug, opening perspectives for the application of this material in anticancer therapy.