Final results of Australasian Gastrointestinal Trials Group ARCTIC study: an audit of raltitrexed for patients with cardiac toxicity induced by fluoropyrimidines

Toxoplasma gondii-Derived Exosomes: A Potential Immunostimulant and Delivery System for Tumor Immunotherapy Superior to Toxoplasma gondii

Immunotherapies such as immune checkpoint blockade (ICB) therapy and chimeric antigen receptor T-cell (CAR-T) therapy have ushered in a new era of tumor treatment. However, most patients do not benefit from immunotherapy due to limitations such as narrow indications, low response rates, and high rates of adverse effects. Toxoplasma gondii (T. gondii), a specialized intracellular protozoan, can modulate host immune responses by inhibiting or stimulating cytokines. The ability of T. gondii to enhance an organism's immune response was found to have a direct anti-tumor effect and enhance the sensitivity of patients with tumors to ICB therapy. However, the application of T. gondii for tumor therapy faces several challenges, such as biosafety concerns. Exosomes, a subtype of extracellular vesicle that contains active components such as proteins, nucleic acids, and lipids, have become effective therapeutic tools for various diseases, including tumors. Parasites, such as T. gondii, mediate the communication of pathogens with immune cells and modulate host cellular immune responses through exosomes. Growing evidence indicates that T. gondii-derived exosomes mediate communication between pathogens and immune cells, modulate host immune responses, and have great potential as new tools for tumor therapy. In this review, we highlight recent advances in isolation and identification techniques, profiling analysis, host immunomodulatory mechanisms, and the role of T. gondii-derived exosomes in tumor immunotherapy. Additionally, we emphasize the potential of T. gondii-derived exosomes as delivery platform to enhance anti-tumor efficacy in combination with other therapies. This review proposes that T. gondii-derived exosomes may serve as a novel tool for tumor immunotherapy owing to their ability to activate host immune function and properties such as high modifiability, stability, and low toxicity. This work will assist in promoting the application of parasite exosomes in tumor therapy.

Efficacy of hepatic arterial infusion chemotherapy in patients with primary liver cancer with portal vein tumor thrombosis: a comparative analysis of different perfusion chemotherapeutic regimens

BACKGROUND

Portal vein tumor thrombosis (PVTT) commonly occurs in patients with primary liver cancer (PLC). Transarterial chemoembolization (TACE) is a treatment for patients with PLC and PVTT. Some studies have shown that combining TACE therapy with hepatic arterial infusion chemotherapy (HAIC) might improve the survival rate of PLC patients with PVTT. However, few studies have compared the different regimens of PLC with PVTT. We aimed to compare the differences between the oxaliplatin + raltetrexed regimen and FOLFOX regimen.

METHODS

We divided the 248 patients into two groups. There were 60 patients in the oxaliplatin + ratitetrexed group and 74 patients in the FOLFOX group. The primary endpoints were OS and PFS. The secondary endpoints were ORR and adverse events. We used SPSS software, the Kaplan-Meier method, the t test, and the rank sum test to compare the differences between the two groups.

RESULTS

The median OS was 10.82 months in the oxaliplatin + raltitrexed group and 8.67 months in the FOLFOX group. The median PFS time was greater in the oxaliplatin + raltitrexed group (10.0 months) than that in the FOLFOX group (7.1 months). The ORR was greater in the oxaliplatin + raltitrexed group than that in the FOLFOX group (18.3% vs. 13.5%; P = 0.445). The DCR in the oxaliplatin + raltitrexed group was higher than that in the FOLFOX group (70.0% vs. 64.8%; P = 0.529). However, in the subgroup analysis, the difference between them was more significant in the type II PVTT subgroup. The OS was 12.08 months in the oxaliplatin + raltitrexed group and 7.26 months in the FOLFOX group (P = 0.008). The PFS was 11.68 months in the oxaliplatin + raltitrexed group and 6.26 months in the FOLFOX group (P = 0.014). In the right branch of type II PVTT, the OS was 13.54 months in the oxaliplatin + raltitrexed group and 6.89 months in the FOLFOX group (P = 0.015), and the PFS was 13.35 months in the oxaliplatin + raltitrexed group and 6.27 months in the FOLFOX group (P = 0.030). The incidence of adverse reactions was similar between the two groups.

CONCLUSIONS

Compared with the FOLFOX regimen, the oxaliplatin + raltitrexed chemoembolization regimen had longer OS, PFS time and ORR and DCR and it was safe and tolerable.

Irinotecan plus raltitrexed as second-line treatment in locally advanced or metastatic colorectal cancer patients: a prospective open-label, single-arm, multi-center, phase II study

BACKGROUND

Colorectal cancer is the third most common cancer and the second leading cause of cancer death. There are limited therapeutic options for the treatment of locally advanced or metastatic colorectal cancers which fail first-line chemotherapy. Phase I/II studies showed that the combined application of the raltitrexed and irinotecan has significant synergistic effect and acceptable toxicity. However, most of these previous studies have relatively small sample size.

METHODS

This is a prospective open-label, single-arm, multi-center, Phase II trial. Brief inclusion criteria: patients were aged 18 to 75 years with locally advanced or metastatic colorectal cancer after failure of 5-FU and oxaliplatin therapy. Enrolled patients received raltitrexed (3 mg/m2, d1) and irinotecan (180 mg/m2, d1) each 21-day cycle until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival, and the secondary endpoints were disease control rate, objective response rate, overall survival and safety.

RESULTS

A total of 108 patients were enrolled between September 2016 and May 2020. The median age was 61 years, ECOG 1 score accounts for 67.6%, the rest were ECOG 0. A total of 502 cycles were completed, with an average of 4.6 cycles and a median of 4 cycles. 108 patients were evaluated, with an objective response rate of 17.6%, and disease control rate of 76.9%. The median follow-up time was 27 months (range:3.1-61.0 m) at data cut-off on March 2023. Median progression-free survival was 4.9 months (95% CI 4.1-5.7) and median overall survival was 13.1 months (95% CI 12.2-15.5). The most common adverse events that were elevated are alanine aminotransferase increased, aspartate aminotransferase increased, fatigue, diarrhoea, neutrocytopenia, thrombocytopenia, hypohemoglobin, and leukocytopenia. Most of the adverse events were Grade I/II, which were relieved after symptomatic treatment, and there were no treatment-related cardiotoxicities and deaths.

CONCLUSIONS

The combination of raltitrexed and irinotecan as second-line treatment for mCRC could be a reliable option after failure of standard 5-Fu-first-line chemotherapy in locally advanced or metastatic colorectal cancers, especially for patients with 5-FU intolerance (cardiac events or DPD deficiency patients).

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03053167, registration date was 14/2/2017.

Natural killer cell-derived exosome-based cancer therapy: from biological roles to clinical significance and implications

Natural killer (NK) cells are important immune cells in the organism and are the third major type of lymphocytes besides T cells and B cells, which play an important function in cancer therapy. In addition to retaining the tumor cell killing function of natural killer cells, natural killer cell-derived exosomes cells also have the characteristics of high safety, wide source, easy to preserve and transport. At the same time, natural killer cell-derived exosomes are easy to modify, and the engineered exosomes can be used in combination with a variety of current cancer therapies, which not only enhances the therapeutic efficacy, but also significantly reduces the side effects. Therefore, this review summarizes the source, isolation and modification strategies of natural killer cell-derived exosomes and the combined application of natural killer cell-derived engineered exosomes with other antitumor therapies, which is expected to accelerate the clinical translation process of natural killer cell-derived engineered exosomes in cancer therapy.

Detailed analysis of metastatic colorectal cancer patients who developed cardiotoxicity on another fluoropyrimidine and switched to S-1 treatment (subgroup analysis of the CardioSwitch-study)

BACKGROUND AND PURPOSE

The CardioSwitch-study demonstrated that patients with solid tumors who develop cardiotoxicity on capecitabine or 5-fluorouracil (5-FU) treatment can be safely switched to S-1, an alternative fluoropyrimidine (FP). In light of the European Medicines Agency approval of S-1 in metastatic colorectal cancer (mCRC), this analysis provides more detailed safety and efficacy information, and data regarding metastasectomy and/or local ablative therapy (LAT), on the mCRC patients from the original study.

MATERIALS AND METHODS

This retrospective cohort study was conducted at 12 European centers. The primary endpoint was recurrence of cardiotoxicity after switch. For this analysis, safety data are reported for 78 mCRC patients from the CardioSwitch cohort (N = 200). Detailed efficacy and outcomes data were available for 66 mCRC patients.

RESULTS

Data for the safety of S-1 in mCRC patients were similar to the original CardioSwitch cohort and that expected for FP-based treatment, with no new concerns. Recurrent cardiotoxicity (all grade 1) with S-1-based treatment occurred in 4/78 (5%) mCRC patients; all were able to complete FP treatment. Median progression-free survival from initiation of S-1-based treatment was 9.0 months and median overall survival 26.7 months. Metastasectomy and/or LAT was performed in 33/66 (50%) patients, and S-1 was successfully used in recommended neoadjuvant/conversion or adjuvant-like combination regimens and schedules as for standard FPs.

INTERPRETATION

S-1 is a safe and effective FP alternative when mCRC patients are forced to discontinue 5-FU or capecitabine due to cardiotoxicity and can be safely used in the standard recommended regimens, settings, and schedules.

Raltitrexed induces apoptosis through activating ROS-mediated ER stress by impeding HSPA8 expression in prostate cancer cells

Prostate cancer is the most common malignant tumor in males, which frequently develops into castration-resistant prostate cancer (CRPC). CRPC metastasis is the main reason for its high mortality rate. At present, it lacks effective treatment for patients with CRPC. Raltitrexed (RTX) has been shown to be effective in the treatment of colorectal cancer. However, the effect of RTX on prostate cancer and the underlying mechanism remain unknown. In the current study, we found that RTX could dose-dependently inhibit proliferation, migration, colony formation and induce apoptosis in DU145 and PC-3 cells. RTX also increased ROS generation in prostate cancer cells. Pretreatment with N-acetyl-L-cysteine (NAC) significantly prevented RTX-induced cell apoptosis and endoplasmic reticulum (ER) stress signaling activation in prostate cancer cells. Additionally, we found RTX-induced ROS generation and ER stress activation depended on the expression of heat shock protein family A member 8 (HSPA8). Over-expression of HSPA8 could alleviate RTX-induced cell apoptosis, ROS generation and ER stress signaling activation. Finally, our study also showed that RTX attenuated the tumor growth of prostate cancer in the DU145 xenograft model and significantly downregulated HSPA8 expression and activated ER stress signaling pathway in tumor tissues. Our study is the first to reveal that RTX induces prostate cancer cells apoptosis through inhibiting the expression of HSPA8 and further inducing ROS-mediated ER stress pathway action. This study suggests that RTX may be a novel promising candidate drug for prostate cancer therapy.

Efficacy and safety of raltitrexed-eluting CalliSpheres® bead transarterial chemoembolization in patients with intermediate-stage hepatocellular carcinoma: a single-arm, prospective study

Background

The most common loadable chemotherapeutic drugs in drug-eluting bead transarterial chemoembolization (DEB-TACE) include doxorubicin, epirubicin, etc. CalliSpheres® beads have exhibited efficient loadability and eluting characteristics for raltitrexed as well as in vitro and animal experiments. However, the efficacy and safety of raltitrexed-loaded DEB-TACE in patients with intermediate-stage hepatocellular carcinoma (HCC) remain unclear.

Objectives

To assess the efficacy and safety of raltitrexed-loaded DEB-TACE in patients with intermediate-stage HCC.

Design

The study was conducted as a single-arm prospective study.

Methods

This study was a prospective, single-arm trial conducted between June 2019 and June 2022. CalliSpheres® beads loaded with raltitrexed were used in the DEB-TACE procedure. The follow-up lasted for at least 1 year or until death. The primary endpoint was overall survival (OS), and the secondary endpoints were time to progression (TTP), progression-free survival (PFS), objective response rate (ORR), and adverse events (AEs).

Results

The 6-month ORR and disease control rates were 90.1% and 93.8%, respectively. The median OS was 33.0 months. The 1-, 2-, and 3-year survival rates were 95.1%, 82.1%, and 43.6%, respectively. Child-Pugh class and bilobar disease occurrence were identified as independent OS predictors. The median TTP and PFS were 22.7 and 19.8 months, respectively. Eleven (11.5%) patients experienced at least one grade 3 AE, and serious AEs were reported in five participants (5.2%). No patient experienced grade 4 or 5 AEs.

Conclusion

Raltitrexed-loaded DEB-TACE is feasible, safe, and effective in patients with intermediate-stage HCC.

Trial registration

This trial was registered at www.chictr.org.cn under the identifier: 1900024097 on 25 June 2019.

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.

S-1 as an alternative treatment after 5-fluorouracil-induced coronary vasospasm in a patient with small bowel adenocarcinoma: a case report

5-Fluorouracil (5-FU) is a chemotherapeutic agent used worldwide to treat various solid tumors. It may cause adverse cardiotoxic events, the most common of which is coronary vasospasm. Recently, the 2022 European Society for Medical Oncology guidelines for metastatic colorectal cancer recommended S-1 as an alternative therapy after 5-FU-induced cardiotoxicity; however, only limited data on Asian patients are available. Here, we report a case of safe administration of S-1 to a 72-year-old Japanese female patient with metastatic small bowel adenocarcinoma who developed 5-FU-induced coronary vasospasm. While receiving modified FOLFOX6 (5-FU plus leucovorin and oxaliplatin) as palliative chemotherapy, she experienced chest pain with electrocardiographic ST elevation. Chemotherapy was temporarily suspended, but treatment was resumed by switching from modified FOLFOX6 to SOX (S-1 plus oxaliplatin) as the tumor began to worsen. Owing to the adverse event of enteritis, the patient's treatment was switched to S-1 monotherapy after cycle 3, and S-1 monotherapy was continued without any cardiotoxicity. S-1 may be a promising alternative therapy after 5-FU-induced cardiotoxicity.

Engineered exosomes from different sources for cancer-targeted therapy

Exosome is a subgroup of extracellular vesicles, which has been serving as an efficient therapeutic tool for various diseases. Engineered exosomes are the sort of exosomes modified with surface decoration and internal therapeutic molecules. After appropriate modification, engineered exosomes are able to deliver antitumor drugs to tumor sites efficiently and precisely with fewer treatment-related adverse effects. However, there still exist many challenges for the clinical translation of engineered exosomes. For instance, what sources and modification strategies could endow exosomes with the most efficient antitumor activity is still poorly understood. Additionally, how to choose appropriately engineered exosomes in different antitumor therapies is another unresolved problem. In this review, we summarized the characteristics of engineered exosomes, especially the spatial and temporal properties. Additionally, we concluded the recent advances in engineered exosomes in the cancer fields, including the sources, isolation technologies, modification strategies, and labeling and imaging methods of engineered exosomes. Furthermore, the applications of engineered exosomes in different antitumor therapies were summarized, such as photodynamic therapy, gene therapy, and immunotherapy. Consequently, the above provides the cancer researchers in this community with the latest ideas on engineered exosome modification and new direction of new drug development, which is prospective to accelerate the clinical translation of engineered exosomes for cancer-targeted therapy.

Preliminary outcomes of DEB-TACE loaded with raltitrexed in the treatment of unresectable or recurrent hepatocellular carcinoma

PURPOSE

Raltitrexed shows therapeutic effects and safety in many types of malignant tumors. However, reports of the clinical outcomes of raltitrexed-based transarterial chemoembolization (TACE) or drug-eluting beads TACE (DEB-TACE) in the treatment of hepatocellular carcinoma (HCC) are rare. We aim to report the preliminary outcomes of DEB-TACE loaded with raltitrexed in patients with unresectable or recurrent HCC.

METHODS

From June 2018 to March 2020, 29 patients with unresectable or recurrent HCC were recruited from our department and treated by DEB-TACE loaded with raltitrexed. Overall survival and progression-free survival were the primary end points. Tumor response was investigated by using the modified response evaluation criteria in solid tumors (mRECIST) criteria.

RESULTS

A total of 49 sessions of DEB-TACE were performed, with a technique success rate of 100%. The overall response rate and disease control rate at 1, 3, and 6 months after DEB-TACE were 72.0% and 96.0%, 57.1% and 85.7%, 47.6% and 66.7% respectively. The median progression-free survival and overall survival was 25.7 and 33.9 months, respectively. The 6-, 24- and 36-month overall survival rates were 88.4%, 66.3% and 46.3%, respectively. Minor complications were observed in 17 patients (58.6%), with no treatment-related mortality or severe adverse events. The most common treatment-related complications were abdominal pain (41.4%) and elevated ALT/AST (27.6%).

CONCLUSION

DEB-TACE loaded with raltitrexed is suggested as a safe, feasible, efficacious palliative regimen in unresectable or recurrent HCC patients.

The puzzling clinical presentation of fluoropyrimidines cardiotoxicity

The cardiotoxicity of fluoropyrimidines (FP) [5-Fluorouracil and Capecitabine] is often reported as acute cardiac ischemia with rest typical angina, signs of ischemia at electrocardiogram (ECG), and ventricular kinetics abnormalities. However, silent ischemia, effort-related toxicity, and ventricular arrhythmias (VA) have been also described. The aim of this study is to report a consecutive series of 115 patients with FP cardiotoxicity observed in a single center both within clinical prospective studies and during the clinical routine. The clinical presentation widely varied as regards symptoms, ECG abnormalities, and clinical outcomes. We report also the strategies used to prevent cardiotoxicity in a subgroup of 35 patients who continued o rechallenged FP therapy after cardiotoxicity. In nearly half of the patients, the cardiotoxicity was triggered by physical effort. Typical angina was rare: the symptoms were absent in 51% of cases and were atypical in half of the other cases. ST-segment elevation and VA were the most frequent ECG abnormality; however, ST segment depression or negative T waves were the only abnormalities in 1/3 of the cases. Troponins essays were often within the normal limits, even in presence of extensive signs of ischemia. The most effective strategy to prevent cardiotoxicity at rechallenge was reducing FP dosage and avoiding physical effort. Anti-ischemic therapies were not always effective. Raltitrexed was a safe alternative to FP. Fluoropyrimidine cardiotoxicity shows a wide variety of clinical presentations in real life, from silent ischemia to atypical symptoms, acute coronary syndrome, left ventricular dysfunction (LVD), VA, or complete atrio-ventricular block. Physical effort is the trigger of cardiotoxicity in nearly half of the cases. The recognition of cardiotoxicity cannot rely on symptoms only but requires an active screening with ECG and stress test in selected cases.

Raltitrexed regulates proliferation and apoptosis of HGC-27 cells by upregulating RSK4

Background

Raltitrexed is a specific inhibitor of thymidylate synthase and a potential chemotherapeutic agent for the treatment of advanced gastric cancer. In this study, we investigated the effect of raltitrexed on the proliferation of HGC-27 human gastric cancer cells and its potential underlying molecular mechanism(s).

Methods

RT-qPCR and western blotting were used to quantify RSK4 levels. Colony formation and flow cytometry assays were used to assess HGC-27 cell proliferation, cell cycle progression, mitochondrial membrane potential, and apoptosis. The expression of cell cycle and apoptosis markers were determined by western blotting.

Results

Our results demonstrate that raltitrexed upregulated RSK4 mRNA and protein levels in HGC-27 cells. Moreover, raltitrexed significantly inhibited tumor cell colony formation, arrested the cell cycle, decreased the mitochondrial membrane potential, and induced apoptosis. We observed that raltitrexed was capable of upregulating the expression of Bax, cyclin A1, and CDK3, and downregulating the expression of Bcl-2 and cleaved caspase-3. Importantly, siRNA-mediated RSK4 knockdown significantly reduced the inhibitory effect of raltitrexed on cell proliferation and its promotion of cell apoptosis. Moreover, silencing of RSK4 inhibited the raltitrexed-induced upregulation of cytochrome C. In addition, the changes in molecular markers related to the cell cycle and apoptosis induced by raltitrexed were reduced upon RSK4 depletion.

Conclusion

Our study shows that RSK4 is a key target of raltitrexed in the regulation of gastric cancer cell proliferation, cell cycle progression, and apoptosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40360-022-00605-2.

Clinical Outcomes of Drug-Eluting Bead Transarterial Chemoembolization Loaded with Raltitrexed for the Treatment of Unresectable or Recurrent Hepatocellular Carcinoma

OBJECTIVES

Although raltitrexed shows therapeutic effects in many types of malignant tumors, the therapeutic effects and safety of drug-eluting bead transarterial chemoembolization (DEB-TACE) loaded with raltitrexed for the treatment of hepatocellular carcinoma (HCC) are rare. This study aimed to investigate the safety and efficacy of DEB-TACE with raltitrexed-loaded CalliSpheres beads (CB) in patients with unresectable or recurrent HCC.

METHODS

Between May 2018 and October 2021, 41 patients with unresectable or recurrent HCC treated by DEB-TACE loaded with raltitrexed were retrospectively enrolled. The primary end points were overall survival and progression-free survival. The response evaluation criteria in solid tumors (RECIST) criteria and modified RECIST criteria (mRECIST) were used to assess the tumor response after the DEB-TACE procedure.

RESULTS

A total of 79 DEB-TACE procedures were successfully performed, and the technical success rate was 100%. The overall response rate and disease control rate assessed by mRECIST criteria were 76.9% and 88.5%, 62.5% and 70.8%, and 35.3% and 47.1%, respectively, at 1, 3, and 6 months postprocedure. The mean progression-free survival and overall survival were 21.6 ± 3.6 and 43.7 ± 5.8 months, respectively. The 6-, 24-, and 36-month overall survival rates were 86.8%, 62.7%, and 57.1%, respectively. Minor complications were observed in 21 patients (51.2%), with no treatment-related mortality or severe adverse events. The most common treatment-related complications were abdominal pain (48.8%) and nausea (29.3%).

CONCLUSION

DEB-TACE with raltitrexed-loaded CB suggests a feasible, safe, and efficacious palliative regimen in unresectable or recurrent HCC patients.

Oxaliplatin Eluting CalliSpheres Microspheres for the Treatment of Unresectable or Recurrent Hepatocellular Carcinoma

Aim: Drug-eluting beads-transarterial chemoembolization (DEB-TACE) has been widely used in unresectable and advanced hepatocellular carcinoma (HCC). However, no study reported the clinical outcomes of drug-eluting beads TACE (DEB-TACE) with oxaliplatin-eluting CalliSpheres microspheres in the treatment of HCC. This study reports the preliminary outcomes of DEB-TACE loaded with oxaliplatin for the treatment of patients with unresectable or recurrent HCC.

Methods: From November 2019 to November 2021, 29 patients with unresectable or recurrent HCC were recruited from our department and treated by DEB-TACE loaded with oxaliplatin. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were disease control rate and safety. Tumor response was investigated at 1, 3, and 6 months after DEB-TACE according to the criteria of the response evaluation in solid tumor (RECIST) criteria and the modified RECIST criteria (mRECIST). Survival curve was generated with the Kaplan–Meier method.

Results: A total of 49 DEB-TACE sessions were performed, with a technical success rate of 100%. The overall response rate and disease control rate were 52.4 and 95.2%, 64.7 and 76.5%, and 54.5 and 63.3%, respectively, at 1, 3, and 6 months after DEB-TACE (mRECIST). The PFS was 5.9 months, and the median overall survival was 18.8 months. The 6- and 12-month overall survival rate was 82.5% and 67.5%, respectively, No treatment-related mortality or severe adverse events were observed. Minor complications were observed in 21 patients (72.4%), and abdominal pain (41.4%) was the most common treatment-related complication.

Conclusion: DEB-TACE loaded with oxaliplatin-eluting CalliSpheres microspheres could be a safe, feasible, and efficacious palliative regimen in unresectable or recurrent HCC patients.

Assessment of the targeted effect of Sijunzi decoction on the colorectal cancer microenvironment via the ESTIMATE algorithm

Objective

Sijunzi decoction (SJZD) was used to treat patients with colorectal cancer (CRC) as an adjuvant method. The aim of the study was to investigate the therapeutic targets and pathways of SJZD towards the tumor microenvironment of CRC via network pharmacology and the ESTIMATE algorithm.

Methods

The ESTIMATE algorithm was used to calculate immune and stromal scores to predict the level of infiltrating immune and stromal cells. The active targets of SJZD were searched in the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and UniProt database. The core targets were obtained by matching the differentially expressed genes in CRC tissues and the targets of SJZD. Then, GO, KEGG and validation in TCGA were carried out.

Results

According to the ESTIMATE algorithm and survival analysis, the median survival time of the low stromal score group was significantly higher than that of the high stromal score group (P = 0.018), while the patients showed no significant difference of OS between different immune groups (P = 0.19). A total of 929 genes were upregulated and 115 genes were downregulated between the stromal score groups (|logFC| > 2, adjusted P < 0.05); 357 genes were upregulated and 472 genes were downregulated between the immune score groups. The component-target network included 139 active components and 52 related targets. The core targets were HSPB1, SPP1, IGFBP3, and TGFB1, which were significantly associated with poor prognosis in TCGA validation. GO terms included the response to hypoxia, the extracellular space, protein binding and the TNF signaling pathway. Immunoreaction was the main enriched pathway identified by KEGG analysis.

Conclusion

The core genes (HSPB1, SPP1, IGFBP3 and TGFB1) affected CRC development and prognosis by regulating hypoxia, protein binding and epithelial-mesenchymal transition in the extracellular matrix.

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.

Managing 5FU Cardiotoxicity in Colorectal Cancer Treatment

Fluorouracil (5FU) is the backbone chemotherapy agent in the treatment of colorectal cancer (CRC). Cardiotoxicity represents an uncommon but serious side effect of treatment with 5FU. Here, we review the current literature on 5FU-cardiotoxicity in the setting of CRC specifically, with a focus on data from the modern era of combination chemotherapy. Despite decades of study, there is little consensus on risk factors and biomarkers for 5FU-cardiotoxicity, nor how patients with CRC should be managed following a cardiotoxicity event. Given the elevated risk of recurrent cardiotoxicity on rechallenge, the use of alternative regimens that do not contain 5FU is a critical aspect of management. Data on the cardiotoxicity risk and efficacy of non-5FU regimens in CRC are therefore reviewed in detail.

Metastatic colorectal cancer: Advances in the folate-fluoropyrimidine chemotherapy backbone

Notwithstanding recent treatment advances in metastatic colorectal cancer (mCRC), chemotherapy with a combination of a fluoropyrimidine and a folate agent, often 5-fluorouracil (5-FU) and leucovorin, remains the backbone of treatment regimens for the majority of patients with mCRC. This is despite a recent focus on molecular-targeted treatments and patient stratification according to mutational status or expression levels of specific genes. Intracellular folate concentration was discovered to be pivotal in the cytotoxic efficacy of 5-FU, paving the way to the current standard combination therapy approach. Subsequent discovery that systemic chemotherapy agents, such as irinotecan and oxaliplatin, can further increase the efficacy of 5-FU-based treatments led to the development of several combination chemotherapy regimens, including FOLFOX, FOLFIRI and FOLFOXIRI. Subsequent efforts to optimise 5-FU-based treatments have focused on 5-FU analogues, initially capecitabine and the combination drug tegafur/gimeracil/oteracil (S-1) and then TAS-102, which has recently been evaluated in phase 3 clinical trials for refractory colorectal cancer. Further approaches taken to improve the efficacy of 5-FU chemotherapy regimens have focused on optimising the route and dosing schedules and regulating folate metabolism. Pharmacokinetic variability caused by the requirement for metabolic conversion of leucovorin has been central to recent research, and the development of agents such as arfolitixorin which bypass the need for metabolic conversion remains promising for future therapeutic candidates. In this review, we summarise the evidence leading to the current treatment regimens employing 5-FU and leucovorin, focusing on recent approaches taken to optimise and refine treatments to improve clinical outcomes in patients with mCRC.

Risk Factors of Fluoropyrimidine Induced Cardiotoxicity among Cancer Patients: A Systematic Review and Meta-analysis

Cancer patients experienced an increased risk of cardiotoxicity during fluoropyrimidine-based chemotherapy (5-fluorouracil or capecitabine). We searched PubMed, PsycINFO, IPA, CINAHL, Web of Science, and ClinicalTrials.gov for studies published between January 1, 1990 and December 31, 2019, in English, examining risk factors for cardiotoxicity induced by fluoropyrimidine. Included study-level data were converted to risk ratios (RRs) and pooled RRs were calculated for meta-analyses using a random-effects method. Among 690 publications identified for abstract and title screening, 22 unique studies were included in the review, and 20 had sufficient data for meta-analyses. Results indicated that patients undergoing capecitabine-based combination therapy had a higher risk than those with monotherapy (pooled RR = 1.61). Patients with pre-existing cardiac disease (pooled RR = 3.26), hypertension (pooled RR = 1.52) or smoking (pooled RR = 2.22) also had higher risks than their counterparts. Developing risk assessment tools to mitigate the risk could be a viable strategy to improve outcomes for cancer patients undergoing fluoropyrimidine-based treatments.

A comparison between raltitrexed plus cisplatin and docetaxel plus cisplatin in concurrent chemoradiation for non-surgical esophageal squamous cell carcinoma

PURPOSE

Chemoradiotherapy (CRT) is considered as a standard treatment for unresectable and inoperable esophageal cancer (EC) patients. However, no consensus has been reached regarding the optimal synchronous chemotherapy regimen and the best combination of radiotherapy and chemotherapy. The aim of this study was to evaluate the efficacy and toxicity of raltitrexed plus cisplatin and docetaxel plus cisplatin to find a safe and effective concurrent chemotherapy schedule.

PATIENTS AND METHODS

Our retrospective study included 151 EC patients treated with raltitrexed and cisplatin (RP) (n=90) or docetaxel and cisplatin (DP) (n=61) from 2011 till 2018. Survival outcomes and treatment related toxicity were analyzed between the two groups.

RESULTS

PFS and OS were 18 and 34 months in the RP group, while 13 and 20 months in the DP group (P=0.118 and P=0.270). The 1-, 2-, 3-year survival rates of the RP group were 71.1, 55.4 and 46.4%. For the DP group, these were 63.9, 44.3 and 37.6%, respectively. Compared with DP group, RP group received a superior CR rate (68.9% versus 52.5%, P=0.041). There was a trend that the total number of toxic reactions in RP group was lower than that in DP group (P=0.058).

CONCLUSIONS

Even RP and DP groups have the similar survival outcomes and toxicity, raltitrexed/cisplatin get a higher complete response rate. Our study suggests that raltitrexed combined with cisplatin is a safe and effective concurrent chemotherapy regimen and it might be used as an alternative for cisplatin/5-FU and cisplatin/docetaxel in CCRT for EC patients.

Fluoropyrimidine-induced cardiotoxicity

Cardio-oncology is a discipline based on early screening, monitoring, and treating chemotherapy-induced cardiotoxicity. There are many chemotherapeutics known for their cardiac toxic effects, including fluoropyrimidines. Fluoropyrimidine represents the cornerstone of many types of cancer and each year almost two million cancer patients undergo this treatment. Fluoropyrimidine-induced cardiotoxicity can be manifested in several forms, from angina pectoris to sudden death. This paper is a review of how the cardiotoxicity of fluoropyrimidines is presented, the mechanisms of its occurrence, its diagnosis, and management.

Efficacy of Chinese herbal injections combined with fluoropyrimidine and oxaliplatin-based chemotherapy for advanced colorectal cancer: A protocol for systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Fluoropyrimidine combined with oxaliplatin-based chemotherapy have become the first-line treatment for advanced colorectal cancer (CRC). Chinese herbal injections (CHIs), as an important part of TCM, have been widely applied as adjunctive treatments to chemotherapy in patients with advanced CRC. However, the efficacy of this combination therapy has not been evaluated comprehensively.

METHODS

We will conduct this systematic review and meta-analysis in accordance with the Preferred Reported Items for Systematic Review and Meta-analysis (PRISMA) guidelines. 7 databases will be searched for related randomized controlled trials (RCTs) from their inception to August 31, 2020: PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure (CNKI), VIP Database for Chinese Technical Periodicals (VIP), SinoMED and Wanfang Database. Two researchers will perform study selection, data extraction, and assessment of risk of bias independently. The primary outcomes are the disease control rate (DCR) and the objective response rate (ORR), the secondary outcomes are progression-free survival (PFS), survival rate, quality of life (QoL) and adverse effects. Cochrane Review Manager (RevMan 5.3) software will be used to analyze the outcomes.

RESULTS AND CONCLUSION

This systematic review will evaluate the efficacy of CHIs and fluoropyrimidine and oxaliplatin-based chemotherapy for advanced CRC so as to provide valuable evidence to the application of CHIs in advanced CRC.

SYSTEMATIC REVIEW REGISTRATION

INPLASY registration number: INPLASY2020100050.

Alternative Treatment Options in Patients with Colorectal Cancer Who Encounter Fluoropyrimidine-Induced Cardiotoxicity

5-Fluorouracil (5-FU) remains to be the backbone of chemotherapy regimens approved for treatment of colorectal cancer and other gastrointestinal cancers and breast cancer. The incidence of cardiotoxicity associated with 5-FU ranges from 1.5-18%. Previous studies also concluded that rechallenging a patient with previous 5-FU cardiotoxicity with either lower dose or another mode of administration could result in repeat of cardiac complication in up to 45% of patients. Nearly 13% of patients died upon re-exposure to 5-FU. Clinical manifestations of cardiac complications of fluoropyrimidines including angina, myocardial infarction, arrhythmias, hypotension, Tako-Tsubo syndrome, heart failure, cardiogenic shock, pericarditis, and even sudden death have been reported. Cardiotoxicity is unpredictable and no alternative chemotherapeutics have been defined so far. The author describes here treatment options for patients with metastatic colorectal cancer who have encountered fluoropyrimidine-induced cardiotoxicity, including switching to a different fluoropyrimidine, switching to a different schedule of intravenous 5-FU, or switching to a non-fluoropyrimidine-containing chemotherapy regimen if one exists. Switching to a non-fluoropyrimidine-containing chemotherapy regimen is usually the most feasible choice for patients with metastatic disease as data on adjuvant setting is usually a fluoropyrimidine or its combination with oxaliplatin at present.

Incidence and risk markers of 5-fluorouracil and capecitabine cardiotoxicity in patients with colorectal cancer

Background: Fluoropyrimidines are mainstay chemotherapeutics in the treatment of gastrointestinal cancers and are also used to treat breast cancer and head and neck cancers. However, 5-flourouracil (5-FU) and capecitabine may induce cardiotoxicity that mostly presents as acute coronary syndromes. We compared the incidence of cardiotoxicity induced by 5-FU and capecitabine in patients with colorectal cancer and sought to identify risk markers for cardiotoxicity.Methods: We reviewed all consecutive patients with colorectal cancer who received 5-FU or capecitabine at one institution in the neoadjuvant (2007-2016), adjuvant (2000-2016) or metastatic setting (2007-2016).Results: Totally, 995 patients received 5-FU and 1241 received capecitabine. The incidence of cardiotoxicity induced by 5-FU was 5.2% [95% confidence interval (CI): 3.8-6.6%] and 4.1% (95% CI: 3.0-5.2%) induced by capecitabine (p = .21). The most common events were angina without ischemia (5-FU: 1.6%, capecitabine: 1.3%, p = .53), angina with ischemia on ECG (5-FU: 0.9%, capecitabine: 0.8%, p = .53), unspecified chest pain (5-FU: 0.9%, capecitabine: 0.6%, p = .34), ST-elevation myocardial infarction (5-FU: 0.5%; capecitabine: 0.4%, p = .76) and non-ST-elevation myocardial infarction (5-FU: 0.7%, capecitabine: 0.5%, p = .50). Cardiac arrest or sudden death occurred in 0.5 and 0.4%, respectively (p = 1). No risk markers for cardiotoxicity induced by 5-FU were identified. In the capecitabine group, ischemic heart disease was a risk marker (odds ratio: 2.9, 95% CI: 1.2-7.0, p = .016).Conclusions: Five percent of patients treated with 5-FU developed cardiotoxicity and 4% treated with capecitabine. Ischemic heart disease was a risk marker for cardiotoxicity induced by capecitabine.

Hyperthermic intraperitoneal chemotherapy with recombinant mutant human TNF-α and raltitrexed in mice with colorectal-peritoneal carcinomatosis

Peritoneum is one of the most common metastatic sites of colorectal cancer (CRC). It has been reported that cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) prolongs the lifespan of patients with peritoneal carcinomatosis of colorectal origin (CRC-PC), while the drugs used for HIPEC are limited. We investigated the application of recombinant mutant human tumor necrosis factor-α (rmhTNF) combined with raltitrexed in the HIPEC treatment in a mice model with CRC-PC. In vitro, we detected the cytotoxicity and apoptosis of human colorectal cancer cells by 3–(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, Western blot, and TdT-mediated dUTP Nick End Labeling (TUNEL) assay. In vivo, we established xenograft models of CRC-PC and assessed the antitumor effect by in vivo imaging, peritoneal cancer index scoring, and TUNEL assay. The results showed that the combination of rmhTNF and raltitrexed under hyperthermia with a temperature of 42°C inhibited the growth of colorectal cancer cells significantly in vitro, and after HIPEC treatments with rmhTNF and raltitrexed, peritoneal tumor growth was prohibited in vivo. Our findings about the efficacy of rmhTNF and raltitrexed used for HIPEC to treat CRC-PC will provide experimental data and basis for their potential clinical application.

Impact statement

Colorectal peritoneal carcinomatosis exhibits poor prognosis and presents a treatment challenge. At present, the main treatment is surgery, supplemented by hyperthermic intraperitoneal chemotherapy (HIPEC), but the drugs used for HIPEC are limited. Our study found that the combination of recombinant mutant human TNF-α (rmhTNF) and raltitrexed (RTX) under hyperthermia with a temperature of 42°C had antitumor effect both in vitro and vivo. The findings will provide experimental data and basis for the potential clinical application of rmhTNF and RTX, which might offer patients a new choice of therapeutic drugs.

Concurrent chemoradiotherapy with raltitrexed and nedaplatin regimen for esophageal squamous cell carcinoma

BACKGROUND

The aim of the study reported here was to evaluate the feasibility and safety of raltitrexed and nedaplatin with concurrent radiotherapy in patients with unresectable, locally advanced esophageal squamous cell carcinoma (ESCC).

METHODS

Eligible patients were adults with newly diagnosed untreated, unresectable esophageal cancer in stages I to IV with lymph node metastases or cervical esophageal cancer. Patients received nedaplatin 25 mg/m per day on day 1-3, raltitrexed 3 mg/m on days 1 repeated every 21 days for 2 cycles, and combined concurrent radiotherapy (2 Gy/fraction, total dose of 60 Gy).

RESULT

Thirty patients were included with squamous cell carcinoma. The median follow-up duration was 24 months. The overall response rate was 90%. The 1-year and 2-year overall survival rates for all patients were 70.4% and 55.7% with a median survival time of 30 months, and the median progression free survival was 20 month. The major toxicities were leukopenia and thrombopenia, with grade 3 to 4 leukopenia and thrombopenia were 50% and 30% of patients.

CONCLUSION

Concurrent chemoradiotherapy with raltitrexed and nedaplatin agents frequently caused myelosuppression but was highly active and suggested to be a promising treatment option for locally advanced ESCC.

Fluorouracil-induced Takotsubo cardiomyopathy causing cardiogenic shock: a case report of clinical and acute cardiac magnetic resonance imaging features

Background

Takotsubo cardiomyopathy (TTS) is an extremely rare complication of fluorouracil containing chemotherapy regimes such as FOLFOX used for colorectal cancer, occurring in only five previous case reports. Due to its potentially fatal outcomes, yet infrequent presence in the literature, it is worthwhile reviewing the clinical features and outcomes of this phenomenon.

Case summary

A 54-year-old lady was admitted with cardiogenic shock. A cardiac magnetic resonance imaging (CMR) showed mid-ventricle to apical hypokinesis and confirmed TTS. She was managed with inotropes and non-invasive ventilation after which she recovered fully both clinically and in her CMR features 6 weeks following discharge.

Discussion

This is the first case showing the acute CMR features of this complication and highlights the need for awareness of this rarely occurring cardiotoxicity. It also shows the potentially fatal phenomenon can be fully reversible when diagnosed and managed promptly even in patients with metastatic cancer and critical illness.

Efficacy and Cardiotoxic Safety Profile of Raltitrexed in Fluoropyrimidines-Pretreated or High-Risk Cardiac Patients With GI Malignancies: Large Single-Center Experience

BACKGROUND

Gastrointestinal (GI) cancer patients may not be considered for therapy with fluoropyrimidines (FPs) because of previous cardiovascular (CV) toxicity or preexisting risk factors; such patients may benefit from raltitrexed-based therapy.

PATIENTS AND METHODS

Patient, tumor, and treatment characteristics, as well as clinical outcomes of all consecutively treated patients with raltitrexed at the Royal Marsden Hospital between October 1998 and July 2011 were examined. GI cancer patients who developed CV toxicity as a result of FPs and those with significant CV risk factors receiving raltitrexed were included in this analysis.

RESULTS

A total of 247 patients (155 and 92 with CV FP-related CV toxicities and significant CV risk factors, respectively) treated with raltitrexed alone or in combination were examined after a median follow-up of 47.1 months. CV toxicity profiles of patients receiving capecitabine (n = 110) and 5-fluorouracil (n = 45) were largely similar. Of raltitrexed-treated patients, 13 (5%) experienced CV toxicities and 1 (< 0.1%) died as a result of myocardial infarction. The median progression-free survival (PFS) and overall survival (OS) were 36.0 months (95% confidence interval [CI], 26.5-48.6) and 44.3 months (95% CI, 33.1-56.8), respectively. The 5-year survival for early stage GI malignancies (n = 140) was 62.0% (95% CI, 50.1-71.9). Median PFS and OS were not reached in this group (interquartile range = 38.4 months to NR); median PFS and OS for advanced GI malignancies (n = 107) were 18.8 (95% CI, 11.9-25.7) and 23.7 months (95% CI, 17.0-26.9), respectively.

CONCLUSION

A raltitrexed-based regimen is well-tolerated therapy with comparable efficacy to FPs in patients with GI malignancies with significant CV toxicities or risk factors.

17-allylamino-17-demethoxygeldanamycin impeded chemotherapy through antioxidant activation via reducing reactive oxygen species-induced cell death

Hyperthermia enhances the anticancer effects of thymidylate synthase (TYMS) inhibitors (raltitrexed, RTX) and improves the precise biochemical mechanisms partially through enhancement of intracellular drug absorption. Recent research focuses on the potential anticancer drug target Heat Shock Protein 90 (HSP90), which could increase the sensitivity of cancer cells to TYMS inhibitors; however, with different HSP90 inhibitors, several research studies finally showed a poor efficacy in preclinical or clinical research. Here, we showed that 17-allylamino-17-demethoxygeldanamycin (17-AAG, HSP90 inhibitor) affects the efficacy of chemotherapy through antioxidant activation-induced resistance. In this study, we found that RTX, alone or in combination with hyperthermia, triggers reactive oxygen species (ROS) exposure and thus induces cell death. Also, the addition of hyperthermia showed more ROS exposure and function. The pharmacologic inhibition of HSP90 reversed the effects of chemotherapeutical treatments, while the overexpression of HSP90 showed no relation with these effects, which demonstrated that dysregulation of HSP90 might have a significant impact on chemotherapeutic treatments. The addition of 17-AAG increased the activation of antioxidant with increased antioxidant enzymes, thus affecting the RTX efficacy.

Cardiovascular safety of oncologic agents: A double-edged sword even in the era of targeted therapies - part 1

INTRODUCTION

Patients with cancer are subject to the cardiotoxic effects of cancer therapy and as more patients survive cancer due to improved treatment they are exposed to various forms of cardiovascular (CV) disease as they age, and vice-versa. Such an interplay of age with both malignancy and CV disease may contribute to increased morbidity and mortality.

AREAS COVERED

This two-part review considers the effects of cancer drug treatment on the CV system. In Part I, the various types of CV and cardiometabolic toxicity of anti-cancer drugs and the possible mechanisms involved are discussed. Also, among the specific oncologic agents, the CV effects of the classical agents and of the large molecule immunological agents (monoclonal antibodies, including immune checkpoint inhibitors) are detailed.

EXPERT OPINION

Oncologic agents produce a variety of CV adverse effects, including cardiomyopathy and heart failure, peri-myocarditis, coronary artery disease, peripheral vascular disease, hypertension (HTN), cardiac arrhythmias, valvular heart disease, and pulmonary HTN. Both the oncologist and the cardiologist need to be aware of such adverse effects and of the specific agents that produce them. They need to join forces to prevent, anticipate, recognize, and manage such complications.

[Fluoropyrimidines cardiac toxicity: 5-fluorouracil, capecitabine, compound S-1 and trifluridine/tipiracil]

The incidence of cardiac toxicity of 5-flurorouracil (5-FU) IV and capecitabine varies from 1.2 to 18%. The physiopathology of this toxicity is still under study, various hypotheses are mentioned. In the absence of identified prophylactic treatment, reintroduction of this cytotoxic is at risk. A discussion between oncologists and cardiologists is essential to estimate the balance between benefit and risk and the careful reintroduction of treatment. An alternative compound might be raltitrexed which is currently the treatment recommended in case of intolerance to fluoropyrimidines. The compound S-1 does not have any cardiac toxicity. Of a total of 2910 patients in phase II or III studies, no grade III or IV cardiovascular events were reported. However, the treatment is not reimbursed in France and therefore not available. The trifluridine/tipiracil, for which approval from French authorities was obtained in November 2016 for patients with metastatic colorectal cancer in progress despite standard treatment lines, does not appear to have cardiac toxicity according to studies published to date. The pivotal phase III study (RECOURSE), that led to this marketing authorization, was performed in 800 patients with metastatic colorectal cancer refractory and only one patient (less than 1% of patients) treated with trifluridine/tipiracil presented an episode of cardiac ischemia. Thus, trifluridine/tipiracil, which is well tolerated, could be an alternative to raltitrexed for patients with cardiovascular history contraindicating or discouraging the use of fluoropyrimidines.

5-fluorouracil and cardiotoxicity: a review

Fluoropyrimidines such as 5-fluorouracil (5-FU) form the foundation of a wide variety of chemotherapy regimens. 5-FU is in fact the third most commonly used chemotherapeutic agent in the treatment of solid malignancies across the world. As with all chemotherapy, balancing the potential benefits of therapy against the risks of drug-related toxicity is crucial when clinicians and patients make shared decisions about treatment. 5-FU is the second most common chemotherapeutic drug associated with cardiotoxicity after anthracyclines, which can manifest as chest pain, acute coronary syndrome/myocardial infarction or death. Nevertheless a widespread appreciation of 5-FU-related cardiotoxicity and its implications is lacking amongst clinicians. In this review, we outline the incidence, possible risk factors, and likely pathophysiological mechanisms that may account for 5-FU-related cardiotoxicity and also highlight potential management strategies for this poorly understood clinical entity.

Cardiotoxicity of 5-fluorouracil and capecitabine in Chinese patients: a prospective study

Background

5-Fluorouracil (5-FU) and capecitabine-associated cardiotoxicity ranging from asymptomatic electrocardiography (ECG) abnormalities to severe myocardial infarction has been reported in a number of studies, but such cardiotoxicity in Chinese patients with malignant diseases has not been investigated to date. In the present study, we aimed to prospectively evaluate the incidence rates and clinical manifestations of 5-FU- and capecitabine-associated cardiotoxicity in cancer patients recruited from multiple centers in China.

Methods

Among the 527 patients who completed the study, 196 received 5-FU-based chemotherapy and 331 received capecitabine-based chemotherapy as either first-line or adjuvant therapy. Adverse events were reported during the treatment and up to 28 days of follow-up. Outcome measures included ECG, myocardial enzymes, cardiac troponin, brain natriuretic peptide and echocardiography. Univariate analysis and logistic regression were performed for subgroup analysis and identification of significant independent variables that are associated with cardiotoxicity of both agents.

Results

In total, 161 of 527 patients (30.6%) experienced cardiotoxicity. The incidence rate of cardiotoxicity was 33.8% (112/331) in the capecitabine group, which was significantly higher than the rate of 25% (49/196) in the 5-FU group (P = 0.0042). 110/527 patients (20.9%) suffered arrhythmia, 105/527 (19.9%) developed ischemic changes, while only 20/527 patients (3.8%) presented heart failure and 6/527 patients (1.1%) had myocardial infarction. Pre-existing cardiac disease, hypertension, capecitabine-based chemotherapy and duration of treatment were identified as significant risk factors associated with cardiotoxicity. The odds ratio were 15.7 (prior history of cardiac disease versus no history), 1.86 (capecitabine versus 5-FU), 1.06 (5–8 versus 1–4 chemotherapy cycles) and 1.58 (hypertension versus no hypertension), respectively.

Conclusions

Cardiotoxicity induced by fluoropyrimidines in the Chinese population may be underestimated in clinical practice. Close monitoring of patients is recommended, especially for those patients at high risk for cardiotoxicity. Possible risk factors are duration of treatment, capecitabine-based chemotherapy, pre-existing cardiac diseases and hypertension.

Trial registration This study was initiated on January 22, 2014 and has been retrospectively registered with the registration number ChiCTR1800015434

The Role of Fluoropirimidines in Gastrointestinal Tumours: from the Bench to the Bed

PURPOSE

Gastrointestinal tumours are one of the most common types of cancer. Therapeutic options include surgery, radiotherapy, local ablation techniques, targeted agents, and chemotherapy. Fluoroprimidines are one of the most active drug families in digestive tumours and remains the cornerstone of the most commonly used chemotherapy schemes.

METHODS

We review the molecular basis of thymidylate synthase inhibition and the mechanisms of action of 5-fluorouracil, next generation oral fluoropyrimidines (capecitabine, tegafur and the latest S-1 and TAS-102) and antifolates.

RESULTS

In addition, mechanisms and biomarkers of resistance and toxicity are explored. Finally, new fluoropyrimidines development and clinical trials ongoing in digestive tumours are reviewed.

CONCLUSIONS

Further research is necessary to avoid resistance mechanisms, improve clinical outcomes and continue reducing toxicities. Until new drugs become available, the optimization of current therapies should be a priority.

Fluoropyrimidine-induced cardiotoxicity

Fluoropyrimidines (5-fluorouracil and capecitabine) are antimetabolite drugs, widely used for the treatment of a variety of cancers, both in adjuvant and in metastatic setting. Although the most common toxicities of these drugs have been extensively studied, robust data and comprehensive characterization still lack concerning fluoropyrimidine-induced cardiotoxicity (FIC), an infrequent but potentially life-threatening toxicity. This review summarizes the current state of knowledge of FIC with special regard to proposed pathogenetic models (coronary vasospasm, endothelium and cardiomyocytes damage, toxic metabolites, dihydropyrimidine dehydrogenase deficiency); risk and predictive factors; efficacy and usefulness in detection of laboratory markers, electrocardiographic changes and cardiac imaging; and specific treatment, including a novel agent, uridine triacetate. The role of alternative chemotherapeutic options, namely raltitrexed and TAS-102, is discussed, and, lastly, we overview the most promising future directions in the research on FIC and development of diagnostic tools, including microRNA technology.

Network meta-analysis of the efficacy of first-line chemotherapy regimens in patients with advanced colorectal cancer

This network meta-analysis compared the short-term and long-term efficacies of first-line chemotherapy regimens in patients with advanced colorectal cancer (CRC). The 10 regimens included folinic acid + 5-fluorouracil + oxaliplatin (FOLFOX), folinic acid + 5-fluorouracil + irinotecan (FOLFIRI), folinic acid + 5-fluorouracil + gemcitabine (FFG), folinic acid + 5-fluorouracil + trimetrexate (FFT), folinic acid + 5-fluorouracil (FF), irinotecan + oxaliplatin (IROX), raltitrexed + oxaliplatin (TOMOX), folinic acid + tegafur-uracil (FTU), raltitrexed, and capecitabine. Electronic searches were performed in the Cochrane Library, PubMed and Embase databases from inception to June 2017. Network meta-analysis combined direct and indirect evidence to obtain odds ratios (ORs) and surface under the cumulative ranking curves (SUCRA) of different chemotherapy regimens for advanced CRC. Fourteen randomized controlled trails (RCTs) covering 4,383 patients with advanced CRC were included. The results revealed that FOLFOX, FOLFIRI, IROX, and TOMOX all showed higher overall response rates (ORRs) than FF or raltitrexed. Compared with raltitrexed, the aforementioned four regimens also had higher 1-year progression-free survival (PFS) rates. In addition, FOLFOX and FOLFIRI exhibited higher disease control rates (DCRs) and 1-year PFS rates than FF or raltitrexed. Cluster analysis revealed that FOLFOX, FOLFIRI, and TOMOX had better short-term and long-term efficacies. These findings suggest FOLFOX, FOLFIRI, and TOMOX are superior to other regimens for advanced CRC. These three regimens are therefore recommended for clinical treatment of advanced CRC.

Raltitrexed plus oxaliplatin-based transarterial chemoembolization in patients with unresectable hepatocellular carcinoma

Raltitrexed has shown efficacy and safety in many tumor types; however, the clinical data on the treatment of hepatocellular carcinoma is rare. In this report, we aim to assess the efficacy and safety of raltitrexed plus oxaliplatin (OXA)-based transarterial chemoembolization (TACE) in patients with unresectable hepatocellular carcinoma (uHCC). Patients with uHCC were recruited from multi-centers in China and assigned randomly to raltitrexed+OXA-based (n=76), fluorouracil+OXA-based (n=76), and doxorubicin+OXA-based (n=75) TACE treatment. The primary end point was overall survival (OS). Tumor response was assessed using response evaluation criteria in solid tumors (RECIST), modified response evaluation criteria in solid tumors (mRECIST), and European Association for the Study of the Liver criteria (EASL). Safety and toxicity were evaluated using the National Cancer Institute Common Toxicity Criteria. The raltitrexed group showed a better disease control rate evaluated using RECIST (raltitrexed vs. fluorouracil vs. doxorubicin: 96.1 vs. 84.2 vs. 86.7%, P=0.05) and a better overall response rate on the basis of mRECIST (67.1 vs. 47.4 vs. 50.7%, P=0.03) and EASL (67.1 vs. 47.4 vs. 49.3%, P=0.02). The median OS and median progression-free survival (PFS) were higher in the raltitrexed group (median OS: 13.4 vs. 9.6 vs. 8.5 months; median PFS: 6.7 vs 4.9 vs 4.6 months). The most common toxicities included elevated aspartate aminotransferase (78.9 vs. 86.8 vs. 81.3%) and abdominal nonspecific pain (68.4 vs. 81.6 vs. 78.7%). No significant differences were found in the overall number of patients who experienced any toxicity. Raltitrexed plus OXA-based TACE suggested a safe and efficacious regimen in uHCC patients. The results warrant further clinical investigation.

A study of peritoneal metastatic xenograft model of colorectal cancer in the treatment of hyperthermic intraperitoneal chemotherapy with Raltitrexed

Peritoneal metastasis of colorectal cancer is one of the most incident and fateful diseases among relapse cases. It shows a certain resistance to systemic chemotherapy. The perfusion system in clinic is complex and hard to be used in fundamental researches. This study aims at evaluating the effect of an improved hyperthermic intraperitoneal chemotherapy with Raltitrexed used in tumor-bearing mice with peritoneal metastatic colorectal carcinoma. The results showed that no severe adverse effect was observed. All control animals developed extensive peritoneal and mesenteric metastatic nodes. Tumor sites in the treatment groups were reduced significantly. The administration dose of Raltitrexed influenced concentration in systemic blood and peritoneal tissues. Temperature promoted the intracellular absorption of Raltitrexed significantly. Our findings reveal that hyperthermic intraperitoneal chemotherapy is an efficient therapy in treating peritoneal metastatic carcinoma in nude mice. It can effectively reduce the extension of carcinoma cells from macro and micro examination. The combination of hyperthermia and Raltitrexed resulted in an improved therapeutic effect on animal models.

Optimizing adjuvant therapy and survivorship care of stage III colon cancer

The MOSAIC trial demonstrated nearly a decade ago that the addition of oxaliplatin to 5-fluorouracil improves outcomes in the adjuvant treatment of colon cancer, but no new agents have been shown to be superior to standard FOLFOX therapy. Oncologists have refined the use of oxaliplatin containing regimens to optimize outcomes, improved patient selection for multi-agent chemotherapy and expanded survivorship care to meet the needs of the growing number of survivors. In this article, we review the historical contexts of current therapy, appropriate staging investigations, the importance of timely initiation of therapy and key survivorship issues. We also discuss exciting opportunities for change, including reduced duration of adjuvant chemotherapy and the use of circulating tumor cells and DNA in surveillance.

A systematic review of raltitrexed-based first-line chemotherapy in advanced colorectal cancer

Raltitrexed is a thymidylate synthase inhibitor belonging to the antimetabolite class of cytotoxic drugs. It is also effective in colorectal cancer (CRC) both as a single agent and in combination with other drugs, in particular in those patients with cardiologic risk factors or previous cardiotoxicity. The efficacy of first-line raltitrexed-based chemotherapy containing oxaliplatin (TOMOX) and irinotecan (TOMIRI) was investigated in this systematic review. Studies that enrolled advanced CRC patients for first-line therapy with TOMOX/TOMIRI combinations were identified using electronic databases (Pubmed, SCOPUS, Web of Science, EMBASE, and the Cochrane Library). A systematic analysis was carried out using Comprehensive Meta Analysis (version 2.2.064) software to calculate the pooled response rate and 95% confidence limits. The median pooled overall survival and progression-free survival were also calculated. Results for TOMOX and TOMIRI studies were compared using the two-sided Student's t-test. We tested for significant heterogeneity using Cochran's χ-test and I index. Twelve studies published between 2001 and 2012 were eligible for this analysis and a total of 735 patients were enrolled in these studies. The overall response rate was 40% (95% confidence interval 34-46%): 43.9% for TOMOX and 34.1% for TOMIRI arms. The weighted median overall survival and progression-free survival times were 14.6 and 6.7 months, respectively. Neutropenia and liver toxicity were more frequent with TOMOX, whereas neutropenia and diarrhea were more frequent with TOMIRI. However, compared with historical FOLFOX and FOLFIRI trials, raltitrexed-based doublets are associated with less neutropenia and gastrointestinal toxicity and uncommon cardiotoxicity. TOMOX and TOMIRI doublets are active as first-line chemotherapy for advanced CRC and seem useful in particular when the use of 5-fluorouracil is contraindicated for cardiac comorbidity.

Inside the biochemical pathways of thymidylate synthase perturbed by anticancer drugs: Novel strategies to overcome cancer chemoresistance

Our current understanding of the mechanisms of action of antitumor agents and the precise mechanisms underlying drug resistance is that these two processes are directly linked. Moreover, it is often possible to delineate chemoresistance mechanisms based on the specific mechanism of action of a given anticancer drug. A more holistic approach to the chemoresistance problem suggests that entire metabolic pathways, rather than single enzyme targets may better explain and educate us about the complexity of the cellular responses upon cytotoxic drug administration. Drugs, which target thymidylate synthase and folate-dependent enzymes, represent an important therapeutic arm in the treatment of various human malignancies. However, prolonged patient treatment often provokes drug resistance phenomena that render the chemotherapeutic treatment highly ineffective. Hence, strategies to overcome drug resistance are primarily designed to achieve either enhanced intracellular drug accumulation, to avoid the upregulation of folate-dependent enzymes, and to circumvent the impairment of DNA repair enzymes which are also responsible for cross-resistance to various anticancer drugs. The current clinical practice based on drug combination therapeutic regimens represents the most effective approach to counteract drug resistance. In the current paper, we review the molecular aspects of the activity of TS-targeting drugs and describe how such mechanisms are related to the emergence of clinical drug resistance. We also discuss the current possibilities to overcome drug resistance by using a molecular mechanistic approach based on medicinal chemistry methods focusing on rational structural modifications of novel antitumor agents. This paper also focuses on the importance of the modulation of metabolic pathways upon drug administration, their analysis and the assessment of their putative roles in the networks involved using a meta-analysis approach. The present review describes the main pathways that are modulated by TS-targeting anticancer drugs starting from the description of the normal functioning of the folate metabolic pathway, through the protein modulation occurring upon drug delivery to cultured tumor cells as well as cancer patients, finally describing how the pathways are modulated by drug resistance development. The data collected are then analyzed using network/netwire connecting methods in order to provide a wider view of the pathways involved and of the importance of such information in identifying additional proteins that could serve as novel druggable targets for efficacious cancer therapy.

Design, synthesis, and anticancer evaluation of long-chain alkoxylated mono-carbonyl analogues of curcumin

Curcumin is a nontoxic phenolic compound that modulates the activity of several cellular targets that have been linked with cancers and other chronic diseases. However, the efficacy of curcumin in the clinic has been limited by its poor bioavailability and rapid metabolism in vivo. We have previously reported the design and discovery of series of 5-carbon linker-containing mono-carbonyl analogues of curcumin (MACs) as anti-cancer agents. In continuation of our ongoing research, we designed and synthesized 37 novel long-chain alkoxylated MACs for anti-cancer evaluation here. The MTS assay was used to determine the cytotoxicity of compounds in gastrointestinal cancer cells. Compounds 5, 28, and 29 showed strongest inhibition against gastric cancer cell proliferation and were subjected to further analysis. The effects of 5, 28, and 29 on cell apoptosis were measured by flow cytometry. Expression levels of Bcl-2, cleaved poly ADP-ribose polymerase (PARP), and pro-caspase-3 were detected by western blotting. Compounds 5, 28, and 29 induced apoptosis in human gastric carcinoma cells, increased PARP cleavage, and decreased expression of Bcl-2 and pro-caspase-3 protein. We then showed that compound 28, which possessed the strongest activity among the test compounds in vitro, exhibited significant tumor inhibition in SGC7901-driven xenograft mouse model. Taken together, the novel compound 28 could be further explored as an effective anticancer agent for the treatment of human gastric cancer.

Standing the test of time: targeting thymidylate biosynthesis in cancer therapy

Over the past 60 years, chemotherapeutic agents that target thymidylate biosynthesis and the enzyme thymidylate synthase (TS) have remained among the most-successful drugs used in the treatment of cancer. Fluoropyrimidines, such as 5-fluorouracil and capecitabine, and antifolates, such as methotrexate and pemetrexed, induce a state of thymidylate deficiency and imbalances in the nucleotide pool that impair DNA replication and repair. TS-targeted agents are used to treat numerous solid and haematological malignancies, either alone or as foundational therapeutics in combination treatment regimens. We overview the pivotal discoveries that led to the rational development of thymidylate biosynthesis as a chemotherapeutic target, and highlight the crucial contribution of these advances to driving and accelerating drug development in the earliest era of cancer chemotherapy. The function of TS as well as the mechanisms and consequences of inhibition of this enzyme by structurally diverse classes of drugs with distinct mechanisms of action are also discussed. In addition, breakthroughs relating to TS-targeted therapies that transformed the clinical landscape in some of the most-difficult-to-treat cancers, such as pancreatic, colorectal and non-small-cell lung cancer, are highlighted. Finally, new therapeutic agents and novel mechanism-based strategies that promise to further exploit the vulnerabilities and target resistance mechanisms within the thymidylate biosynthesis pathway are reviewed.