Chemotherapy for metastatic colon cancer: No effect on survival when the dose is reduced due to side effects

Syntheses of LSD1/HDAC Inhibitors with Demonstrated Efficacy against Colorectal Cancer: In Vitro and In Vivo Studies Including Patient-Derived Organoids

Precedential evidence ascertaining the overexpression of LSD1 and HDACs in colorectal cancer spurred us to design a series of dual LSD1-HDAC inhibitors. Capitalizing on the modular nature of the three-component HDAC inhibitory model, tranylcypromine as a surface recognition motif was appended to zinc-binding motifs via diverse linkers. A compendium of hydroxamic acids was generated and evaluated for in vitro cytotoxicity against HCT-116 cells (human colorectal cancer cell lines). The most potent cell growth inhibitor 2 (GI50 = 0.495 μMm HCT-116 cells) shows promising anticancer effects by reducing colony formation and inducing cell cycle arrest in HCT-116 cells. It exhibits preferential inhibition of HDAC6, along with potent inhibition of LSD1 compared to standard inhibitors. Moreover, Compound 2 upregulates acetyl-tubulin, acetyl-histone H3, and H3K4me2, indicative of LSD1 and HDAC inhibition. In vivo, it demonstrates significant antitumor activity against colorectal cancer, better than irinotecan, and effectively inhibits growth in patient-derived CRC organoids.

Systemic Administration of Cowpea Mosaic Virus Demonstrates Broad Protection Against Metastatic Cancers

The key challenge in cancer treatment is prevention of metastatic disease which is therapeutically resistant and carries poor prognoses necessitating efficacious prophylactic approaches that prevent metastasis and recurrence. It is previously demonstrated that cowpea mosaic virus (CPMV) induces durable antitumor responses when used in situ, i.e., intratumoral injection. As a new direction, it is showed that CPMV demonstrates widespread effectiveness as an immunoprophylactic agent - potent efficacy is demonstrated in four metastatic models of colon, ovarian, melanoma, and breast cancer. Systemic administration of CPMV stimulates the innate immune system, enabling attack of cancer cells; processing of the cancer cells and associated antigens leads to systemic, durable, and adaptive antitumor immunity. Overall, CPMV demonstrated broad efficacy as an immunoprophylactic agent in the rejection of metastatic cancer.

Anticancer Mechanisms and Potential Anticancer Applications of Antimicrobial Peptides and Their Nano Agents

Traditional chemotherapy is one of the main methods of cancer treatment, which is largely limited by severe side effects and frequent development of multi-drug resistance by cancer cells. Antimicrobial peptides (AMPs) with high efficiency and low toxicity, as one of the most promising new drugs to replace chemoradiotherapy, have become a current research hotspot, attracting the attention of worldwide researchers. AMPs are natural-source small peptides from the innate immune system, and certain AMPs can selectively kill a broad spectrum of cancer cells while exhibiting less damage to normal cells. Although it involves intracellular mechanisms, AMPs exert their anti-cancer effects mainly through membrane destruction effect; thus, AMPs also hold unique advantages in fighting drug-resistant cancer cells. However, the poor stability and hemolytic toxicity of peptides limit their clinical application. Fortunately, functionalized nanoparticles have many possibilities in overcoming the shortcomings of AMPs, which provides a huge prospect for better application of AMPs. In this paper, we briefly introduce the characteristics and different sources of AMPs, review and summarize the mechanisms of action and the research status of AMPs used as an anticancer therapy, and finally focus on the further use of AMPs nano agents in the anti-cancer direction.

The 2022 PSOGI International Consensus on HIPEC Regimens for Peritoneal Malignancies: Epithelial Ovarian Cancer

BACKGROUND AND AIM

We report the results of an international consensus on hyperthermic intraperitoneal chemotherapy (HIPEC) regimens for epithelial ovarian cancer (EOC) performed with the following goals: To define the indications for HIPEC To identify the most suitable HIPEC regimens for each indication in EOC To identify areas of future research on HIPEC To provide recommendations for some aspects of perioperative care for HIPEC METHODS: The Delphi technique was used with two rounds of voting. There were three categories of questions: evidence-based recommendations [using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system with the patient, intervention, comparator, and outcome (PICO) method], an opinion survey, and research recommendations.

RESULTS

Seventy-three (67.5%) of 108 invited experts responded in round I, and 68 (62.9%) in round II. Consensus was achieved for 34/38 (94.7%) questions. However, a strong positive consensus that would lead to inclusion in routine care was reached for only 6/38 (15.7%) questions. HIPEC in addition to interval cytoreductive surgery (CRS) received a strong positive recommendation that merits inclusion in routine care. Single-agent cisplatin was the only drug recommended for routine care, and OVHIPEC-1 was the most preferred regimen. The panel recommended performing HIPEC for a minimum of 60 min with a recommended minimum intraabdominal temperature of 41°C. Nephroprotection with sodium thiosulfate should be used for cisplatin HIPEC.

CONCLUSIONS

The results of this consensus should guide clinical decisions on indications of HIPEC and the choice and various parameters of HIPEC regimens and could fill current knowledge gaps. These outcomes should be the basis for designing future clinical trials on HIPEC in EOC.

PD-1 and PD-L1 inhibitors in cold colorectal cancer: challenges and strategies

Colorectal cancer (CRC) is the second most common cause of cancer mortality, with mismatch repair proficient (pMMR) and/or microsatellite stable (MSS) CRC making up more than 80% of metastatic CRC. Programmed death-ligand 1 (PD-L1) and programmed death 1 (PD-1) immune checkpoint inhibitors (ICIs) are approved as monotherapy in many cancers including a subset of advanced or metastatic colorectal cancer (CRC) with deficiency in mismatch repair (dMMR) and/or high microsatellite instability (MSI-H). However, proficient mismatch repair and microsatellite stable (pMMR/MSS) cold CRCs have not shown clinical response to ICIs alone. To potentiate the anti-tumor response of PD-L1/PD-1 inhibitors in patients with MSS cold cancer, combination strategies currently being investigated include dual ICI, and PD-L1/PD-1 inhibitors in combination with chemotherapy, radiotherapy, vascular endothelial growth factor (VEGF) /VEGF receptor (VEGFR) inhibitors, mitogen-activated protein kinase (MEK) inhibitors, and signal transducer and activation of transcription 3 (STAT3) inhibitors. This paper will review the mechanisms of PD-1/PD-L1 ICI resistance in pMMR/MSS CRC and potential combination strategies to overcome this resistance, summarize the published clinical experience with different combination therapies, and make recommendations for future avenues of research.

Cotargeting Phosphoinositide 3-Kinase and Focal Adhesion Kinase Pathways Inhibits Proliferation of NF2 Schwannoma Cells

Neurofibromatosis Type 2 (NF2) is a tumor predisposition syndrome caused by germline inactivating mutations in the NF2 gene encoding the merlin tumor suppressor. Patients develop multiple benign tumor types in the nervous system including bilateral vestibular schwannomas (VS). Standard treatments include surgery and radiation therapy, which may lead to loss of hearing, impaired facial nerve function, and other complications. Kinase inhibitor monotherapies have been evaluated clinically for NF2 patients with limited success, and more effective nonsurgical therapies are urgently needed. Schwannoma model cells treated with PI3K inhibitors upregulate activity of the focal adhesion kinase (FAK) family as a compensatory survival pathway. We screened combinations of 13 clinically relevant PI3K and FAK inhibitors using human isogenic normal and merlin-deficient Schwann cell lines. The most efficacious combination was PI3K/mTOR inhibitor omipalisib with SRC/FAK inhibitor dasatinib. Sub-GI50 doses of the single drugs blocked phosphorylation of their major target proteins. The combination was superior to either single agent in promoting a G1 cell-cycle arrest and produced a 44% decrease in tumor growth over a 2-week period in a pilot orthotopic allograft model. Evaluation of single and combination drugs in six human primary VS cell models revealed the combination was superior to the monotherapies in 3 of 6 VS samples, highlighting inter-tumor variability between patients consistent with observations from clinical trials with other molecular targeted agents. Dasatinib alone performed as well as the combination in the remaining three samples. Preclinically validated combination therapies hold promise for NF2 patients and warrants further study in clinical trials.

Medicinal Characteristics of Withania somnifera L. in Colorectal Cancer Management

Research into tumorigenic pathways can aid in the development of more efficient cancer therapies and provide insight into the physiological regulatory mechanisms employed by rapidly proliferating cancer cells. Due to the severe side effects of cancer chemotherapeutic medications, plant chemicals and their analogues are now explored more frequently for the treatment and prevention of colorectal cancer (CRC), opening the stage for new phytotherapeutic strategies that are considered effective and safe substitutes. Our study aimed to evaluate the medicinal properties of Withania somnifera L. and its safety applications in CRC management. Important databases were rigorously searched for relevant literature, and only 82 full-text publications matched the inclusion requirements from a massive collection of 10,002 titles and abstracts. W. somnifera L. contains a high concentration of active plant-based compounds. The pharmacological activity of the plant from our study has been demonstrated to exert antiproliferation, upregulation of apoptosis, decrease in oxidative stress, downregulation of cyclooxygenase-2 (COX-2), induction of targeted cytotoxic effects on cancerous cells, and exertion of both antiangiogenesis and antimigratory effects. We advise further research before recommending W. somnifera L. for clinical use to identify the optimal concentrations required to elicit beneficial effects in CRC management in humans, singly or in combination.

Fluoroindole chalcone analogues targeting the colchicine binding site of tubulin for colorectal oncotherapy

Colorectal cancer (CRC) is a common malignancy of the gastrointestinal tract with high morbidity and mortality. Our previous studies have demonstrated that indole-chalcone-based compounds targeting tubulin displayed potential cytotoxicity to CRC cells. Herein, three new series of derivatives were systematically designed and synthesized to explore their structure-activity relationship (SAR) against CRC based on prior research. Among them, a representative fluorine-containing analog (FC116) exerted superior efficacy on HCT116 (IC₅₀ = 4.52 nM) and CT26 (IC₅₀ = 18.69 nM) cell lines, and HCT116-xenograft mice with tumor growth inhibition rate of 65.96% (3 mg/kg). Of note, FC116 could also suppress the growth of organoid models (IC₅₀ = 1.8-2.5 nM) and showed adenoma number inhibition rate of 76.25% at the dose of 3 mg/kg in APC^min/+ mice. In terms of mechanism, FC116 could induce endoplasmic reticulum (ER) stress to produce excess reactive oxygen species (ROS), leading to mitochondrial damage to promote the apoptosis of CRC cells by targeting microtubules. Our results support that indole-chalcone compounds are promising tubulin inhibitors and highlight the potential of FC116 to combat CRC.

Pharmacotherapeutic Potential of Aloe secundiflora against Colorectal Cancer Growth and Proliferation

Aloe species are widespread and diverse in African ecosystems, and this commonly correlates to their habitual use as reservoirs of herbal medicine. The side effects associated with chemotherapy and the development of antimicrobial resistance to empirically used antimicrobial drugs are substantial, paving the way for novel phytotherapeutic approaches. This comprehensive study aimed to evaluate and present Aloe secundiflora (A. secundiflora) as a compelling alternative with potential benefits in colorectal cancer (CRC) treatment. Important databases were systematically searched for relevant literature, and out of a large collection of 6421 titles and abstracts, only 68 full-text articles met the inclusion criteria. A. secundiflora possesses an abundant presence of bioactive phytoconstituents in the leaves and roots, including anthraquinones, naphthoquinones, phenols, alkaloids, saponins, tannins, and flavonoids, among others. These metabolites have proven diverse efficacy in inhibiting cancer growth. The presence of innumerable biomolecules in A. secundiflora signifies the beneficial effects of incorporating the plant as a potential anti-CRC agent. Nonetheless, we recommend further research to determine the optimal concentrations necessary to elicit beneficial effects in the management of CRC. Furthermore, they should be investigated as potential raw ingredients for making conventional medications.

Combined Thermosensitive Gel Co-Loaded with Dermaseptin-PP and PTX Liposomes for Effective Local Chemotherapy

Introduction

Chemotherapeutic drugs are often ineffective due to the delivery. Local chemotherapy, which has high drug concentration, low systemic toxicity, and long duration, has shown excellent potential. Cationic antimicrobial peptides have been proved to enhance the tumor cells' uptake of chemotherapeutic drugs through the membrane-breaking effect. In this study, we designed and developed a thermosensitive gel co-loaded with Dermaseptin-PP and paclitaxel liposomes to increase local chemotherapy.

Methods

The paclitaxel liposomes were prepared. Then, it was co-loaded with Dermaseptin-PP in a poloxamer-based thermosensitive gel to obtain Dermaseptin-PP/paclitaxel liposomes gel. The thermosensitivity of gels was investigated by test tube inversion method. The rheology was tested by rheometer. The in vitro cytotoxicity and the permeation in tumor of gels were examined by H157 cells and the 3D cell model, respectively. The retention in tumor and antitumor activity of gels were evaluated by H157 tumor-bearing nude mice.

Results

The particle size of paclitaxel liposomes was 148.97 ± 0.21 nm. The encapsulation rate was 86.1%, and the drug loading capacity was 19.4%. The gels had slow-release and temperature-sensitive properties. The porous 3D network structure of the gels could ensure that the drug was fixed into the tumor. In vitro and in vivo distribution studies showed that Dermaseptin-PP promoted the permeation of the gels in H157 multicellular tumor spheres and achieved longer retention in tumor. In vitro and in vivo antitumor studies demonstrated that Dermaseptin-PP/paclitaxel liposomes gel significantly inhibited the growth of tumors for local chemotherapy with good biosafety.

Conclusion

This study provided a promising nanomedicine platform for combining antimicrobial peptides and chemotherapeutic drugs for local chemotherapy.

Real-Life Effectivity of Dose Intensity Reduction of First-Line mFOLFIRI-Based Treatment of Metastatic Colorectal Cancers: Sometimes Less Is More

Aim: The key purposes of the treatment of metastatic malignancies are to extend survival and maintain the quality of life. Recently it has been emphasized in the scientific literature that the maintenance of maximal dose intensity is not always beneficial. Method: We examined the effectiveness of first-line mFOLFIRI-based treatments used in mCRC indication in 515 patients, treated between 1 January 2013 and 31 December 2018 at the Department of Oncotherapy of the University of Pécs, on a basis of real-world retrospective data analysis. We studied the effect of decreased dose intensity treatment modifications on patient survival. Results: 45% of all patients achieved the optimal relative dose intensity (RDI) of 85%, and the median progression-free and overall survival (mPFS, mOS) were 199 and 578 days, compared to 322 and 743 days, (mPFS p < 0.0002, 1 y (year) PFS OR (odds ratio) 0.39 (95% CI: 0.26−0.56) and mOS p = 0.0781, 2 yrs OS OR 0.58 (95% CI: 0.39−0.85), respectively) in the group of patients not achieving the RDI of 85%. Conclusions: Decreased dose intensity did not reduce the effectiveness of treatment; in fact, there was a significant improvement in most of the analyzed parameters. The option of reduced dose intensity, which shows the same or even better results with less toxicity, should definitely be considered in the future palliative treatment of mCRC patients.

The Impact of Fasting the Holy Month of Ramadan on Colorectal Cancer Patients and Two Tumor Biomarkers: A Tertiary-Care Hospital Experience

BACKGROUND

 Fasting during the holy month of Ramadan is a religious ritual practiced by the majority of Muslims around the globe. This daytime fasting is short-term or intermittent fasting, which may be associated with valuable health benefits, particularly in cancer patients.

METHODS

 A prospective cohort study of pre- and post-fasting evaluation of 37 colorectal cancer (CRC) patients was conducted at King Abdulaziz Medical City (KAMC) and King Abdullah Specialized Children's Hospital (KASCH)-oncology outpatient clinics. The study aimed to assess the impact of fasting during the holy month of Ramadan on the tolerability of chemotherapy side effects and to assess changes in the levels of carcinoembryonic antigen (CEA) and lactate dehydrogenase (LDH) tumor biomarkers, which are primarily associated with certain types of carcinomas, including CRC.

RESULTS

A total of 33 patients (89.2%) had fasted at least part of the month of Ramadan. Twenty-seven patients (73%) reported "Serenity" after fasting during Ramadan with improved tolerability of chemotherapy side effects. However, the results did not reveal any significant difference in the measured laboratory variables between pre-fasting values and by the end of the 30 days of Ramadan. Although statistically insignificant, the levels of CEA and LDH were reduced in 46.9% and 55.6% of patients, respectively. The mean level of CEA in the fasting group was substantially reduced by more than 40%, attributed to the highly significant decline of CEA levels in three patients (p=0.0283). Moreover, there were no significant differences between pre- and post-fasting blood creatinine levels or estimated glomerular filtration rates, ruling out any possible adverse effects of fasting on renal function.

CONCLUSION

The current study confirms the safety and tolerability of intermittent fasting in CRC patients actively receiving chemotherapy, which is consistent with several reports. Nonetheless, the results did not reveal a significant decrease in CEA and LDH tumor biomarkers.

Metastatic Colon Cancer Treatment Using S100A9-Targeted Cowpea Mosaic Virus Nanoparticles

Peritoneal metastases (PMs) occur due to the metastasis of gynecological and gastrointestinal cancers such as ovarian, colon, pancreatic, or gastric tumors. PM outgrowth is often fatal, and patients with PMs have a median survival of 6 months. Cowpea mosaic virus (CPMV) has been shown, when injected intratumorally, to act as an immunomodulator reversing the immunosuppressive tumor microenvironment, therefore turning cold tumors hot and priming systemic antitumor immunity. However, not all tumors are injectable, and PMs especially will require targeted treatments to direct CPMV toward the disseminated tumor nodules. Toward this goal, we designed and tested a CPMV nanoparticle targeted to S100A9, a key immune mediator for many cancer types indicated in cancer growth, invasiveness, and metastasis. Here, we chose to use an intraperitoneal (IP) colon cancer model, and analysis of IP gavage fluid demonstrates that S100A9 is upregulated following IP challenge. S100A9-targeted CPMV particles displaying peptide ligands specific for S100A9 homed to IP-disseminated tumors, and treatment led to improved survival and decreased tumor burden. Targeting CPMV to S100A9 improves preclinical outcomes and harbors the potential of utilizing CPMV for the treatment of IP-disseminated diseases.

β-Catenin-treated peptides effectively inhibit the proliferation of colorectal cancer

To verify the inhibitory mechanism of β-catenin-designed peptides in colorectal cancer(CRC) tumors, the following experiments were performed. In vitro colony formation, Transwell assays, and flow cytometry were performed to assess the biological effects of designed peptides (F18KD, F20A4-7k, F20A4-10k, and F20A3-9k + F20A4-10k + F20A5-9k) in HT-29 cells. In vivo xenograft experiments were performed and treated with peptides. Next, tumors were subjected to Hematoxylin and eosin staining (HE), immunohistochemical, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining assays to evaluate the inhibitory effect of peptides on tumors. β-Catenin levels were quantified via western blotting (WB) and quantitative real-time polymerase chain reaction, and β-catenin was located using confocal laser scanning microscopy. T-cell factor-4 (TCF-4), C-myc, and CCND1 levels were quantified via WB. Results were obtained as following. First, the peptides reduced viability, migration, and invasion; promoted apoptosis; and stabilized the S phase of HT-29 cells. Second, peptides suppressed tumor growth and downregulated the expression of CD34, vascular endothelial growth factor, and β-catenin in tumors. Furthermore, we found that peptides downregulated β-catenin expression in both the cytoplasm and nucleus; TCF-4, C-myc, and CCND1 expression was also downregulated. Notably, β-catenin-targeting peptides had a better inhibitory effect on CRC than non-β-catenin-target peptides, and a combination of peptides exerted a more potent inhibitory effect on CRC than single peptides. It suggested that β-Catenin-targeting peptides promote apoptosis in CRC tumors by inhibiting activation of the Wnt/β-catenin pathway.

The survival impact of palliative chemotherapy dose modifications on metastatic colon cancer

BACKGROUND

An uninterrupted dose of oxaliplatin-based cytotoxic therapy is an essential component in the standard treatment regimen of metastatic colon cancer (mCC). Data on the impacts of dose intensity reduction on the palliative treatment for patients with mCC remain scarce. Hence, this study aimed to investigate the impact of palliative chemotherapy dose modifications (DM) on the survival of patients with mCC.

METHODS

Patients with stage IV colon cancer who received first-line palliative FOLFOX regimen chemotherapy between 2014 until 2018 in the Oncology Department of the National Cancer Institute were conveniently sampled retrospectively to analyse the treatment efficacy. The cumulative dose and duration of chemotherapy received by the patients were summarised as relative dose intensity (RDI) and stratified as High RDI (RDI ≥ 70%) or Low RDI (RDI < 70%). Progression-free survival (PFS) and 2-year overall survival (OS) between the two groups were analysed using Kaplan-Meier survival analysis and Cox proportional hazards models.

RESULTS

Out of the 414 patients identified, 95 patients with mCC were eligible and included in the final analysis. About half of the patients (n = 47) completed the 12-cycle chemotherapy regimen and one patient received the complete (100%) RDI. The overall median RDI was 68.7%. The Low RDI group (n = 49) had a 1.5 times higher mortality risk than the High RDI group [OS, Hazard Ratio (HR) = 1.5, 95% Cl: 1.19-1.82] with a significant median OS difference (9.1 vs. 16.0 months, p <  0.01). Furthermore, patients with lower dose intensity showed double the risk of disease progression (PFS, HR = 2.0, 95% CI: 1.23-3.13) with a significant difference of 4.5 months of median PFS (p <  0.01). Gender and RDI were the independent prognostic factors of both OS and PFS.

CONCLUSION

Reduction in the dose intensity of palliative chemotherapy may adversely affect both disease progression and overall survival among mCC patients.

Anticancer Effects of Vitis vinifera L. Mediated Biosynthesized Silver Nanoparticles and Cotreatment with 5 Fluorouracil on HT-29 Cell Line

The aim of this study was to evaluate the anticancer effects of biosynthesized silver nanoparticles (Vv-AgNPs) from grape (Vitis vinifera L.) seed aqueous extract, alone or in combination with 5-Fluorouracil (5-FU) on HT-29 cell line. Vv-AgNPs were characterized by techniques such as UV-vis spectrophotometer (surface plasmon peak 454 nm), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). HT-29 cells were treated with different concentrations (0-80 μg/mL for MTT) and (0-20 μg/mL for BrdU) of Vv-AgNPs alone and combined with (200 μg/mL) 5-FU for 72 h. The cytotoxic effects were analyzed by [3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyl tetrazolium bromide] (MTT) assay (IC₅₀ values 13.74 and 5.35 μg/mL, respectively). Antiproliferative effects were examined 5-bromo-2'-deoxyuridine (BrdU) assay (IC₅₀ values 9.65 and 5.00 μg/mL, respectively). Activation of caspase-3 and protein expression levels of p53 were determined by Western blotting analysis. It was observed that Vv-AgNPs significantly increased the cleavage of the proapoptotic proteins caspase 3 and obviously enhanced the expression of p53 in a dose-dependent manner. The increased amount of total oxidant status (TOS) in the 10 μg/mL Vv-AgNPs + 5-FU treatment group, despite the increasing amount of total antioxidant status (TAS), caused an increase in Oxidative Stress Index (OSI) compared to the control. In this study, it has been shown in vitro that the use of successfully biosynthesized Vv-AgNPs in combination with 5-FU exhibits synergistic cytotoxic, antiproliferative, apoptotic, and oxidative effects against HT-29 cell line.

Epigallocatechin gallate triggers apoptosis by suppressing de novo lipogenesis in colorectal carcinoma cells

The de novo lipogenesis (DNL) pathway has been identified as a regulator of cancer progression and aggressiveness. Downregulation of key lipogenesis enzymes has been shown to activate apoptosis in cancerous cells. Epigallocatechin gallate (EGCG) inhibits cancer cell proliferation without causing cytotoxicity in healthy cells. The present study aimed to investigate the effects of EGCG on the promotion of apoptosis associated with the DNL pathway inhibition in cancer cells, both in vitro and in vivo. We observed that two colorectal cancer cell lines (HCT116 and HT-29) had a higher cytotoxic response to EGCG treatment than hepatocellular carcinoma cells, including HepG2 and HuH-7. EGCG treatment decreased cell viability and increased mitochondrial damage-triggered apoptosis in both HCT116 and HT-29 cancer cells. Additionally, we treated mice transplanted with HCT116 cells with 30 or 50 mg·kg-1 EGCG for 7 days to evaluate the apoptotic effects of EGCG treatment in a xenograft mouse model of cancer. We observed a decrease in intracellular fatty acid levels, which suggested that EGCG-induced apoptosis was associated with a decrease in fatty acid levels in cancer. Suppression of ATP synthesis by EGCG indicated that cell death induction in cancer cells could be mediated by shared components of the DNL and energy metabolism pathways. In addition, EGCG-induced apoptosis suppressed the expression of the phosphorylation protein kinase B and extracellular signal-regulated kinase 1/2 signaling proteins in tumors from xenografted mice. Cytotoxic effects in unaffected organs and tissues of the mouse xenograft model were absent upon EGCG treatment.

The comparative anti-cancer effects of krill oil and oxaliplatin in an orthotopic mouse model of colorectal cancer

BACKGROUND

Our in vitro studies demonstrated that krill oil (KO) has anti-cancer potential. This study aimed to compare the anti-cancer effects of KO with a commonly used chemotherapeutic drug, oxaliplatin and to identify the molecular mechanisms associated with KO supplementation in a mouse model of colorectal cancer (CRC).

METHODS

Thirty-six male Balb/c mice were randomly divided into six groups. Five groups received standard chow diet supplemented with KO (150 g/kg)), corn oil (150 g/kg), KO combined with ½ dose of oxaliplatin (1.5 mg/kg body weight/3 times per week), corn oil combined with ½ dose of oxaliplatin (1.5 mg/kg body weight/3 times per week), or a full dose of oxaliplatin (3 mg/kg body weight/3 times per week). The control (sham) group received a standard chow diet. Treatments started three weeks before and continued for three weeks after orthotopic CRC induction. The number of metastases, tumour weight and volume were quantified ex-vivo. The expression of cytochrome c, cleaved caspase-9 and -3, DNA damage, PD-L1, PD-L2 and HSP-70 were determined.

RESULTS

A significant reductions in the weight and volume of tumours were observed in mice treated with KO and KO plus a ½ dose of oxaliplatin compared to the sham group, similar to oxaliplatin-treated mice. KO, and KO plus ½ dose of oxaliplatin significantly increased the expression of cytochrome c, cleaved caspase-9 and -3, and DNA damage and decreased expression of PD-L1, PD-L2 and HSP-70 in tumour tissues compared to the sham group.

CONCLUSIONS

The in vivo anti-cancer effects of KO are comparable with oxaliplatin. Thus, dietary KO supplementation has a great potential as a therapeutic/adjunctive agent for CRC treatment.

Evaluation of antitumoral effect of mistletoe fruit extract on Ehrlich ascites tumor cells with muse cell analyzer and argyrophilic nucleolar organizer region staining method

Introduction

Mistletoe has been used alone or as a complementary therapy in the treatment of different diseases for years. In this study, the antitumoral effect of mistletoe fruit extract on Ehrlich ascites tumor (EAT) cells was evaluated.

Materials and Methods

EAT cells from preformed stock mice were transferred to culture dishes containing 5-fluorouracil (5-FU) and mistletoe extracts at different doses (100, 200, 400, and 800 μg/ml). These cells were incubated at 37 °C in an environment with 95% humidity and 5% CO2. At the end of the incubations, the apoptosis status of the cells, cell cycle, mitochondrial membrane potential, and proliferation status with the argyrophilic (Ag) nucleolar organizer region staining (NORs) method were evaluated.

Results

As a result, it was observed that the mistletoe fruit extract and 5-FU induce apoptosis of EAT cells. It was concluded that the 5-FU substance arrests the cell cycle at the G0/G1 stage, while the mistletoe arrests the cell cycle at the S and G2/M stages. The depolarization rate of the mistletoe treated cells was higher. As a result of the evaluation made with the AgNORs method, it was seen that mistletoe and 5-FU could be effective in reducing the proliferation of EAT cells.

Conclusions

It was seen that mistletoe fruit extract could be effective in stimulating the apoptosis and depolarization of cancer cells. The results of other studies in the literature and our study support each other. It was concluded that the mistletoe plant may be useful in cancer treatment.

Ultra-performance liquid chromatography-tandem mass spectrometry for simultaneous determination of 12 anti-tumor drugs in human plasma and its application in therapeutic drug monitoring

The effectiveness and safety of anti-tumor drugs are clinically important issues, and their therapeutic drug monitoring (TDM) is recommended. This study aimed to develop an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for simultaneous TDM and exploration of clinical pharmacokinetics of anti-tumor drugs, including cyclophosphamide, ifosfamide, cisplatin, methotrexate, pemetrexed disodium, capecitabine, 5-fluorouracil, gemcitabine, doxorubicin, fulvestrant, tamoxifen, and irinotecan. After magnetic solid-phase extraction of plasma samples, the isotope internal standards and 12 anti-tumor drugs were separated using a ZORBAX Eclipse Plus C18 column (50.0 × 2.1 mm, 1.7 µm) with water containing 0.1% formic acid and acetonitrile as the mobile phase in a total run time of 5.0 min. The developed UPLC-MS/MS method was validated based on the Chinese Pharmacopoeia and the US Food and Drug Administration guidelines for bioanalytical method validation, including assessment of specificity, calibration curves, carryover, accuracy, crosstalk, precision, stability, recovery, dilution integrity, incurred sample reanalysis, and matrix effect. The results showed that a simple, fast, reliable, and specific UPLC-MS/MS method was developed and validated, and all the performance characteristics of the method met the requirements. The response function was established for concentration range of 0.10-25.00 μg/mL for gemcitabine, cyclophosphamide, ifosfamide, methotrexate, pemetrexed disodium, capecitabine, 5-fluorouracil, and cisplatin, and 0.05-12.50 μg/mL for doxorubicin, fulvestrant, tamoxifen, and irinotecan, with a coefficient of correlation of>0.9984 for all the compounds. The precision and accuracy of all the analytes were<6.5% and 5.9%, respectively. Hence, it could be used for TDM and exploration of pharmacokinetics of the aforementioned 12 anti-tumor drugs.

Cannabinoids, Medical Cannabis, and Colorectal Cancer Immunotherapy

Colorectal cancer is a major public health problem. Unfortunately, currently, no effective curative option exists for this type of malignancy. The most promising cancer treatment nowadays is immunotherapy which is also called biological or targeted therapy. This type of therapy boosts the patient's immune system ability to fight the malignant tumor. However, cancer cells may become resistant to immunotherapy and escape immune surveillance by obtaining genetic alterations. Therefore, new treatment strategies are required. In the recent decade, several reports suggest the effectiveness of cannabinoids and Cannabis sativa extracts for inhibiting cancer proliferation in vitro and in vivo, including intestinal malignancies. Cannabinoids were shown to modulate the pathways involved in cell proliferation, angiogenesis, programmed cell death and metastasis. Because of that, they are proposed as adjunct therapy for many malignancies. By far less information exists on the potential of the use of cannabis in combination with immunotherapy. Here, we explore the possibility of the use of cannabinoids for modulation of immunotherapy of colon cancer and discuss possible advantages and limitations.

Nannocystin ax, an eEF1A inhibitor, induces G1 cell cycle arrest and caspase-independent apoptosis through cyclin D1 downregulation in colon cancer in vivo

Colorectal cancer (CRC) is one of the most common causes of cancer-related death worldwide. Nannocystin ax (NAN), a 21-membered cyclodepsipeptide initially isolated from myxobacteria of the Nannocystis genus, was found to target the eukaryotic elongation factor 1A (eEF1A). The current study was designed to evaluate the anticancer effect and underlying mechanisms of NAN with in vitro and in vivo models. Results showed that NAN induced G1 phase cell cycle arrest and caspase-independent apoptosis in HCT116 and HT29 human CRC cells. NAN significantly downregulated cyclin D1 level in a short time, but NAN did not affect the transcription level and ubiquitin-dependent degradation of cyclin D1. Furthermore, NAN treatment directly targeted eEF1A and partially decreased the synthesis of new proteins, contributing to the downregulation of cyclin D1. Besides, NAN significantly suppressed tumor growth in the zebrafish xenograft model. In conclusion, NAN triggered G1 phase cell cycle arrest through cyclin D1 downregulation and eEF1A-targeted translation inhibition and promoted caspase-independent apoptosis in CRC cells.

HIPEC Methodology and Regimens: The Need for an Expert Consensus

BACKGROUND

Hyperthermic intraperitoneal chemotherapy (HIPEC) is performed with a wide variation in methodology, drugs, and other elements vital to the procedure. Adoption of a limited number of regimens could increase the collective experience of peritoneal oncologists, make comparison between studies more meaningful, and lead to a greater acceptance of results from randomized trials. This study aimed to determine the possibility of standardizing HIPEC methodology and regimens and to identify the best method of performing such a standardization.

METHODS

A critical review of preclinical and clinical studies evaluating the pharmacokinetic aspects of different HIPEC drugs and drug regimens, the impact of hyperthermia, and the efficacy of various HIPEC regimens as well as studies comparing different regimens was performed.

RESULTS

The preclinical and clinical data were limited, and studies comparing different regimens were scarce. Many of the regimens were neither supported by preclinical rationale or data nor validated by a dose-escalating formal phase 1 trial. All the regimens were based on pharmacokinetic data and did not take chemosensitivity of peritoneal metastases into account. Personalized medicine approaches such as patient-derived tumor organoids could offer a solution to this problem, although clinical validation is likely to be challenging.

CONCLUSIONS

Apart from randomized trials, more translational research and phases 1 and 2 studies are needed. While waiting for better preclinical and clinical evidence, the best way to minimize heterogeneity is by an expert consensus that aims to identify and define a limited number of regimens for each indication and primary site. The choice of regimen then can be tailored to the patient profile and its expected toxicity and the methodology according regional factors.

Targeting Colorectal Cancer with Conjugates of a Glucose Transporter Inhibitor and 5-Fluorouracil

Overexpression of glucose transporters (GLUTs) in colorectal cancer cells is associated with 5-fluorouracil (1, 5-FU) resistance and poor clinical outcomes. We designed and synthesized a novel GLUT-targeting drug conjugate, triggered by glutathione in the tumor microenvironment, that releases 5-FU and GLUTs inhibitor (phlorizin (2) and phloretin (3)). Using an orthotopic colorectal cancer mice model, we showed that the conjugate exhibited better antitumor efficacy than 5-FU, with much lower exposure of 5-FU during treatment and without significant side effects. Our study establishes a GLUT-targeting theranostic incorporating a disulfide linker between the targeting module and cytotoxic payload as a potential antitumor therapy.

Management of colorectal cancer in the era of COVID-19: Challenges and suggestions

The Coronavirus (COVID-19) pandemic had a huge impact on all sectors around the world. In particular, the healthcare system has been subject to an enormous pressure that has surpassed its ability in many instances. Additionally, the pandemic has called for a review of our daily medical practices, including our approach to colorectal cancer management where treatment puts patients at high risk of virus exposure. Given their higher median age, patients are at an increased risk for severe symptoms and complications in cases of infection, especially in the setting of immunosuppression. Therefore, a review of the routine colorectal cancer practices is needed to minimize risk of exposure. Oncologists should weigh risk of exposure versus the patient's oncologic benefits when approaching management. In addition, treatment protocols should be modified to minimize hospital visits and admissions while maintaining the same treatment efficacy. In this review, we will focus on challenges that colorectal cancer patients face during the pandemic, while highlighting the priority in each case. We will also discuss the evidence for potential modifications to existing treatment plans that could reduce infectious exposure without compromising care. Finally, we will discuss the impact of the socio-economic difficulties faced by Lebanese patients due to a poor economy toppled by an unexpected pandemic.

PEGylated Nanographene Oxide in Combination with Near-Infrared Laser Irradiation as a Smart Nanocarrier in Colon Cancer Targeted Therapy

Anti-cancer therapies that integrate smart nanomaterials are the focus of cancer research in recent years. Here, we present our results with PEGylated nanographene oxide particles (nGO-PEG) and have studied their combined effect with near-infrared (NIR) irradiation on low and high invasive colorectal carcinoma cells. The aim is to develop nGO-PEG as a smart nanocarrier for colon cancer-targeted therapy. For this purpose, nGO-PEG nanoparticles' size, zeta potential, surface morphology, dispersion stability, aggregation, and sterility were determined and compared with pristine nGO nanoparticles (NPs). Our results show that PEGylation increased the particle sizes from 256.7 nm (pristine nGO) to 324.6 nm (nGO-PEG), the zeta potential from -32.9 to -21.6 mV, and wrinkled the surface of the nanosheets. Furthermore, nGO-PEG exhibited higher absorbance in the NIR region, as compared to unmodified nGO. PEGylated nGO demonstrated enhanced stability in aqueous solution, improved dispensability in the culture medium, containing 10% fetal bovine serum (FBS) and amended biocompatibility. A strong synergic effect of nGO-PEG activated with NIR irradiation for 5 min (1.5 W/cm^-2 laser) was observed on cell growth inhibition of low invasive colon cancer cells (HT29) and their wound closure ability while the effect of NIR on cellular morphology was relatively weak. Our results show that PEGylation of nGO combined with NIR irradiation holds the potential for a biocompatible smart nanocarrier in colon cancer cells with enhanced physicochemical properties and higher biological compatibility. For that reason, further optimization of the irradiation process and detailed screening of nGO-PEG in combination with NIR and chemotherapeutics on the fate of the colon cancer cells is a prerequisite for highly efficient combined nanothermal and photothermal therapy for colon cancer.

How successful is liver resection for colorectal cancer liver metastases in patients over 75 years old?

Backgrounds/Aims

As populations age, an increased incidence of colorectal cancer will generate an increase in colorectal cancer liver metastases (CRLM). In order to guide treatment decisions, this study aimed to identify the contemporary complication rates of elderly patients undergoing liver resection for CRLM in a, centralised, UK centre.

Methods

All patients undergoing operative procedures for CRLM between January 2013 and January 2019 were included. Patient, tumour and operative data were analysed, including the prognostic marker; tumour burden score.

Results

339 operations were performed on 289 consecutive patients with CRLM (272 patients <75 years old, 67 patients ≥75 years old). Median age was 66 years (range 20-93). There was no difference in major complication rates between the two age cohorts (6.65 vs. 6.0%, p=0.847) or operative mortality (1.1% vs. 1.4%, p=0.794). Younger patients had higher R1 resection rates (20.4% vs. 4.5%, p=0.002) and post-operative chemotherapy rates (60.3% vs. 35.8%, p< 0.001). The 1, 3 and 5-year OS was 90.2%, 70.5% and 52.3% respectively, median 70 months, with no difference between age cohorts (p=0.772). Tumour Burden score and operation type were independent predictors of overall survival.

Conclusions

Liver resection for CRLM in patients 75 years and older is feasible, safe and confers a similar 5-year survival rate to younger patients. The current outcomes from surgery are better than historical datasets.

Survival and relative dose intensity of 5-fluorouracil, oxaliplatin and irinotecan in real-life treatment of metastatic colorectal cancer

Introduction

Combinations of 5-fluorouracil/leucovorin (5-FU/LV) with oxaliplatin (FOLFOX) or irinotecan (FOLFIRI) are part of standard treatments for metastatic colorectal cancer (mCRC). For these molecules, the impact of a low relative dose intensity (RDI) on survival is not sufficiently known in real-life.

Material and methods

Data were collected retrospectively from patients treated in our center for an unresectable mCRC with FOLFOX or FOLFIRI as a first-line treatment. To study the impact on progression-free survival (PFS) and overall survival (OS), patients were divided into high and low RDI according to the median RDI of 5-FU on one end, and the median RDI of oxaliplatin or irinotecan (OXA-IRI) on the other.

Results

In our population of 75 patients, the median age was 67.1 years and 77% of patients were treated with FOLFIRI. Patients with high RDI for OXA-IRI had better PFS compared to patients with low RDI (hazard ratio [HR], 0.58; p = 0.03). There was no statistically significant difference in PFS for patients with high RDI for 5-FU (HR, 0.66; p = 0.09). No difference was found in overall survival according to the RDI of OXA-IRI (HR, 0.72; p = 0.18) or 5-FU (HR, 0.77; p = 0.29). RDI had no significant impact on toxicities.

Conclusions

Our analysis suggests that a low RDI of oxaliplatin and irinotecan has a negative effect on PFS. RDI had no significant effect on OS in our cohort. The clinical benefit of maintaining high RDI in these patients appears low.

Combining Correlated Outcomes and Surrogate Endpoints in a Network Meta-Analysis of Colorectal Cancer Treatments

This study aimed to investigate the efficacy and safety of systemic therapies in the treatment of unresectable advanced or metastatic colorectal cancer. Predicted hazard ratios (HRs) and their 95% credible intervals (CrIs) for overall survival (OS) were calculated from the odds ratio (OR) for the overall response rate and/or HR for progression-free survival using multivariate random effects (MVRE) models. We performed a network meta-analysis (NMA) of 49 articles to compare the efficacy and safety of FOLFOX/FOLFIRI±bevacizumab (Bmab)/cetuximab (Cmab)/panitumumab (Pmab), and FOLFOXIRI/CAPEOX±Bmab. The NMA showed significant OS improvement with FOLFOX, FOLFOX+Cmab, and FOLFIRI+Cmab compared with that of FOLFIRI (HR = 0.84, 95% CrI = 0.73-0.98; HR = 0.76, 95% CrI = 0.62-0.94; HR = 0.80, 95% CrI = 0.66-0.96, respectively), as well as with FOLFOX+Cmab and FOLFIRI+Cmab compared with that of FOLFOXIRI (HR = 0.69, 95% CrI = 0.51-0.94 and HR = 0.73, 95% CrI = 0.54-0.97, respectively). The odds of adverse events grade ≥3 were significantly higher for FOLFOX+Cmab vs. FOLFIRI+Bmab (OR = 2.34, 95% CrI = 1.01-4.66). Higher odds of events were observed for FOLFIRI+Pmab in comparison with FOLFIRI (OR = 2.16, 95% CrI = 1.09-3.84) and FOLFIRI+Bmab (OR = 3.14, 95% CrI = 1.51-5.89). FOLFOX+Cmab and FOLFIRI+Bmab showed high probabilities of being first- and second-line treatments in terms of the efficacy and safety, respectively. The findings of the efficacy and safety comparisons may support the selection of appropriate treatments in clinical practice. PROSPERO registration: CRD42020153640.

DSTYK Promotes Metastasis and Chemoresistance via EMT in Colorectal Cancer

Objective

Tumor metastasis and resistance to chemotherapy are two critical factors that contribute to the high death rate of colorectal cancer (CRC) patients. Metastasis is facilitated by the epithelial-mesenchymal transition (EMT) of tumor cells, which has emerged not only as a fundamental process during metastasis, but is also a key process leading to chemoresistance of cancer cells. However, the underlying mechanisms of EMT in CRC cell remain unknown. Here, we aim to assess the role of dual serine/threonine and tyrosine protein kinase (DSTYK) in CRC metastasis and chemoresistance.

Methods

To study the role of DSTYK in TGF-β-induced EMT, we employed techniques including Crispr/Cas9 knockout (KO) to generate DSTYK KO cell lines, RT-PCR to detect the mRNA expression, immunofluorescence analyses, and western blots to detect protein levels of DSTYK in the following 4 cell lines: control LS411N-TβRII and LS411N-TβRII/DSTYK KO, control LS513 and LS513/DSTYK KO cells, treated with/without TGF-β. The effects of DSTYK on apoptosis were investigated by MTT assays, flow cytometry assays, and TUNEL assays. The expression of DSTYK in CRC patients and its correlation with EMT markers were determined by bioinformatics analysis. For in vivo analysis, both xenograft and orthotopic tumor mouse models were employed to investigate the function of DSTYK in chemoresistance and metastasis of tumors.

Results

In this study, we demonstrate that the novel kinase DSTYK promotes both TGF-β-induced EMT and the subsequent chemoresistance in CRC cells. DSTYK KO significantly attenuates TGF-β–induced EMT and chemoresistance in CRC cells. According to the Gene Expression Omnibus (GEO) database, the expression of DSTYK is not only positively correlated to the expression of TGF-β, but proportional to the death rate of CRC patients as well. Evidently, the expression of DSTYK in the metastatic colorectal cancer samples from patients was significantly higher than that of primary colorectal cancer samples. Further, we demonstrate in mouse models that chemotherapeutic drug treatment suppresses the growth of DSTYK KO tumors more effectively than control tumors.

Conclusion

Our findings identify DSTYK as a novel protein kinase in regulating TGF-β–mediated EMT and chemoresistance in CRC cells, which defines DSTYK as a potential therapeutic target for CRC therapy.

Herbal melanin inhibits colorectal cancer cell proliferation by altering redox balance, inducing apoptosis, and modulating MAPK signaling

Background

Colorectal carcinoma is one of the most deadly cancers that requests effective and safe chemotherapy. Evaluation of natural product-based anticancer drugs as adjuvant treatment with fewer side effects is largely unexplored research fields. Herbal melanin (HM) is an extract of the seed coats of Nigella sativa that modulates an inflammatory response through toll-like receptor 4 (TLR4). This TLR4 receptor is also involved in the modulation of apoptosis. We therefore explored the anticancer potential of HM and specifically its effect on the molecular mechanisms underlying adenocarcinoma and metastatic colorectal cancer (mCRC) cell death in vitro.

Methods

Cell viability was evaluated using the MTT assay. Cellular reactive oxygen species (ROS), glutathione levels, and apoptotic status were assessed using fluorometric and colorimetric detection methods. HM-induced apoptotic and other signaling pathways were investigated using Western blot technology and mitochondrial transition pore assay kit. TLR4 receptor downregulation and blockade were performed using siRNA technology and neutralizing antibody, respectively.

Results

Our results showed that HM inhibited the proliferation of the colorectal adenocarcinoma HT29 and mCRC SW620 cell lines. Furthermore, HM enhanced ROS production and decreased glutathione levels. HM-induced apoptosis was associated with mitochondrial outer membrane permeability and cytochrome c release, inhibition of the Bcl2 family proteins, and activation of caspase-3/-7. In addition, HM modulated MAPK pathways by activating the JNK pathway and by inhibiting ERK phosphorylation. TLR4 receptor downregulation enhanced HM-induced apoptosis while TLR4 receptor blockade partially alleviated HM-inhibited ERK phosphorylation.

Conclusion

Altogether, these findings indicate that HM exerts pro-apoptotic effects and inhibits MAPK pathway through TLR4 in mCRC and colorectal adenocarcinoma cells, suggesting HM as a promising natural-based drug for the treatment of colorectal cancer.

A retrospective analysis of plasma concentration monitoring of fluorouracil in patients with advanced colorectal cancer

Objectives

To analyse the results of fluorouracil (5-FU) plasma concentration monitoring in patients with advanced colorectal cancer after 5-FU treatment, and to provide a reference for the application prospect of 5-FU plasma concentration monitoring technology.

Methods

A retrospective analysis was performed with advanced colorectal cancer patients treated with 5-FU from March 2015 to August 2018. The results of plasma concentration monitoring of 5-FU, severe adverse reactions, and anti-tumour efficacy were analysed.

Results

Among 47 patients, 5-FU plasma concentration monitoring was carried out a total of 289 times. The area under the receiver operating characteristic (ROC) curve (AUC) reflecting 5-FU exposure in vivo was 2.8-158 mg*h/L (41±94.6 mg*h/L). Mean AUC range within the target range (20-30 mg*h/L) for each patient was observed in 28.8% of patients. The overall incidence of related severe adverse reactions in the AUC ≤30 mg*h/L group was lower than that in the >30 mg*h/L group (24.0% and 50.0%, respectively) (p=0.06), and the incidence of severe neutropenia was 12.0% and 40.9%, respectively (p=0.05). The disease control rate and overall response rate of the AUC <20 mg*h/L group was lower than that of the ≥20 mg*h/L group: 83.3% vs 97.1% (p=0.19) and 25.0% vs 51.4% (p = 0.10), respectively.

Conclusions

The 5-FU plasma concentration monitoring technique can improve the safety and efficacy of 5-FU administration to advanced colorectal cancer patients. It is expected to become an important means to individualise 5-FU use in the Chinese population.

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.

The rationale of dose-response curves in selecting cancer drug dosing

Drug development for cancer chemotherapy has an interesting history. A mix of serendipity, animal, cell line, and standard pharmacological principles of dose, dose-response, dose-concentration, dose intensity and combination therapies have been used to develop optimal dosing schedules. However in practice, significant gaps in the translation of preclinical to clinical dosing schedules persist, and clinical development has instead moved to new drug development. A older chemotherapies are still the backbone of most solid tumour schedules, therapeutic drug monitoring has emerged as a method for optimising the dose for individual patients.