Triplet (FOLFOXIRI) versus doublet (FOLFOX or FOLFIRI) backbone chemotherapy as first-line treatment of metastatic colorectal cancer: A systematic review and meta-analysis

Evolution and current trends in the management of colorectal cancer liver metastasis

Metastatic colorectal cancer (mCRC) is a major cause of cancer-related death, with a 5-year relative overall survival of up to 20%. The liver is the most common site of distant metastasis in colorectal cancer (CRC), with about 50% of CRC patients metastasizing to their liver over the course of their disease. Complete liver resection is the primary modality of treatment for resectable colorectal cancer liver metastasis (CRLM), with an overall 5-year survival rate of up to 58%. However, only 15% to 20% of patients with CRLM are deemed suitable for resection at presentation. For unresectable diseases, the median survival of patients remains low even with the best chemotherapy. In recent decades, the management of CRLM has continued to evolve with the expansion of resection criteria, novel targeted systemic therapies, and improved locoregional therapies. However, due to the heterogeneity of the CRC patient population, the optimal evaluation of treatment options for CRLM remains complex. Therefore, effective management requires a multidisciplinary team to help define resectability and devise a personalized treatment approach, from the initial diagnosis to the final treatment.

Outcomes of Hepatic Artery-Based Therapies and Systemic Multiagent Chemotherapy in Unresectable Colorectal Liver Metastases: A Systematic Review and Meta-analysis

BACKGROUND

Treatment of unresectable colorectal liver metastases (UCRLM) includes locoregional and systemic therapy. A comprehensive analysis capturing long-term outcomes of these treatment options has not been performed.

OBJECTIVE

A systematic review and meta-analysis was performed to calculate pooled outcomes of hepatic artery infusion with systemic chemotherapy (HAI-S), transarterial chemoembolization with systemic chemotherapy (TACE-S), transarterial radioembolization with systemic chemotherapy (TARE-S), doublet (FOLFOX, FOLFIRI), and triplet chemotherapy (FOLFOXIRI).

METHODS

Outcomes included overall survival (OS), progression-free survival (PFS), rate of conversion to resection (CTR), and response rate (RR).

RESULTS

A total of 32, 7, 9, and 14 publications were included in the HAI-S, TACE-S, and TARE-S chemotherapy arms. The 6/12/24/36-month OS estimates for HAI-S, TACE-S, TARE-S, FOLFOX, FOLFIRI, and FOLFOXIRI were 97%/80%/54%/35%, 100%/83%/40%/14%, 82%/61%/34%/21%, 96%/83%/53%/36%, and 96%/93%/72%/55%. Similarly, the 6/12/24/36-month PFS estimates were 74%/44%/19%/14%, 66%/20%/9%/3%, 57%/23%/10%/3%, 69%/30%/12%/7%, and 88%/55%/18%/11%. The corresponding CTR and RR rates were 31, 20%, unmeasurable (TARE-S), 35, 53; and 49, 45, 45, 50, 80%, respectively. The majority of chemotherapy studies included first-line therapy and liver-only metastases, whereas most HAI-S studies were pretreated. On subgroup analysis in first-line setting with liver-only metastases, the HAI-S arm had comparable outcomes to FOLFOXIRI and outperformed doublet chemotherapy regimens. Although triplet chemotherapy appeared to outperform other arms, high toxicity and inclusion of potentially resectable patients must be considered while interpreting results.

CONCLUSIONS

HAI-S and multiagent chemotherapy are effective therapies for UCRLM. To make definitive conclusions, a randomized trial with comparable patient characteristics and line of therapy will be required. The upcoming EA2222 PUMP trial may help to address this question.

Exploration of novel isoxazole-fused quinone derivatives as anti-colorectal cancer agents through inhibiting STAT3 and elevating ROS level

Colorectal cancer (CRC) is trending to be a major health problem throughout the world. Therapeutics with dual modes of action have shown latent capacity to create ideal anti-tumor activity. Signal transducer and activator of transcription 3 (STAT3) has been proved to be a potential target for the development of anti-colon cancer drug. In addition, modulation of tumor redox homeostasis through deploying exogenous reactive oxygen species (ROS)-enhancing agents has been widely applied as anti-tumor strategy. Thus, simultaneously targeting STAT3 and modulation ROS balance would offer a fresh avenue to combat CRC. In this work, we designed and synthesized a novel series of isoxazole-fused quinones, which were evaluated for their preliminary anti-proliferative activity against HCT116 cells. Among these quinones, compound 41 exerted excellent in vitro anti-tumor effect against HCT116 cell line with an IC50 value of 10.18 ± 0.4 nM. Compound 41 was proved to bind to STAT3 by using Bio-Layer Interferometry (BLI) assay, and can significantly inhibit phosphorylation of STAT3. It also elevated ROS of HCT116 cells by acting as a substrate of NQO1. Mitochondrial dysfunction, apoptosis, and cell cycle arrest, which was caused by compound 41, might be partially due to the inhibition of STAT3 phosphorylation and ROS production induced by 41. Moreover, it exhibited ideal anti-tumor activity in human colorectal cancer xenograft model and good safety profiles in vivo. Overall, this study provided a novel quinone derivative 41 with excellent anti-tumor activity by inhibiting STAT3 and elevating ROS level, and gave insights into designing novel anti-tumor therapeutics by simultaneously modulation of STAT3 and ROS.

FOLFOXIRI plus cetuximab as conversion therapy for unresectable RAS/BRAF wild-type left-sided colorectal cancer with liver-limited metastases: a prospective dual-center pilot study

Purpose

To explore the efficacy and safety of FOLFOXIRI plus cetuximab regimen as conversion therapy for patients with unresectable RAS/BRAF wild-type colorectal liver-limited metastases (CLM).

Patients and methods

This was a dual-center, phase II trial with the rate of no evidence of disease (NED) achieved as the primary endpoint. All enrolled patients with initially unresectable left-sided RAS/BRAF wild-type colorectal liver-limited metastases received a modified FOLFOXIRI plus cetuximab regimen as conversion therapy.

Results

Between October 2019 and October 2021, fifteen patients were enrolled. Nine patients (60%) achieved NED. The overall response rate (ORR) was 92.9%, and the disease control rate (DCR) was 100%. The median relapse-free survival (RFS) was 9 (95% CI: 0-20.7) months. The median progression-free survival (PFS) was 13.0 months (95% CI: 5.7-20.5), and the median overall survival (OS) was not reached. The most frequently occurring grade 3-4 adverse events were neutropenia (20%), peripheral neurotoxicity (13.3%), diarrhea (6.7%), and rash acneiform (6.7%).

Conclusion

The FOLFOXIRI plus cetuximab regimen displayed tolerable toxicity and promising anti-tumor activity in terms of the rate of NED achieved and response rate in patients with initially unresectable left-sided RAS/BRAF wild-type CLM. This regimen merits further investigation.

Camptothesome-based combination nanotherapeutic regimen for improved colorectal cancer immunochemotherapy

Camptothesome is a sphingomyelin-conjugated camptothecin (SM-CSS-CPT) nanovesicle that fortified the therapeutic delivery of CPT in diverse cancer types. To mitigate the Camptothesome-induced IDO1 negative feedback mechanism, we had co-encapsulated, indoximod (IND, IDO1 inhibitor) into Camptothesome using doxorubicin-derived IND (DOX-IND). To maximize the therapeutic potential of DOX-IND/Camptothesome, herein, we first dissected the synergistic drug ratio (DOX-IND/SM-CSS-CPT) via systematical in vitro screening. DOX-IND/Camptothesome with optimal drug ratio synchronized in vivo drug delivery with significantly higher tumor uptake compared to free drugs. This optimum DOX-IND/Camptothesome outperformed the combination of Camptothesome, Doxil and IND or other IDO1 inhibitors (BMS-986205 or epacadostat) in treating mice bearing late-stage MC38 tumors, and combination with immune checkpoint blockade (ICB) enabled it to eradicate 60 % of large tumors. Further, this optimized co-delivery Camptothesome beat Folfox and Folfiri, two first-line combination chemotherapies for colorectal cancer in antitumor efficacy and exhibited no side effects as compared to the severe systemic toxicities associated with Folfox and Folfiri. Finally, we demonstrated that the synergistic DOX-IND/Camptothesome was superior to the combined use of Onivyde + Doxil + IND in curbing the advanced orthotopic CT26-Luc tumors and eliminated 40 % tumors with complete metastasis remission when cooperated with ICB, eliciting stronger anti-CRC immune responses and greater reversal of immunosuppression. These results corroborated that with precise optimal synergistic drug ratio, the therapeutic potential of DOX-IND/Camptothesome can be fully unleased, which warrants further clinical investigation to benefit the cancer patients.

Age-related trends in the incidence of metastatic colorectal cancer from 2010 to 2019 in the USA

Aim: To evaluate temporal changes in metastatic colorectal cancer (mCRC), incidence, and use of chemotherapy treatment by age group using real-world data (RWD) from the USA. Methods: A retrospective, observational study describing temporal trends in mCRC incidence and FOLFOXIRI treatment by age group using a nationwide database of commercially and Medicare Advantage-insured patients from 2010 to 2019. Results: Incidence of mCRC increased by 22.1 and 14.9% in the 18-49 and 50-64 years cohorts, respectively, and decreased by 21.6% in the ≥65 years cohort. Overall, younger patients were more likely to receive FOLFOXIRI treatment versus older patients. Conclusion: The shifting age distribution of mCRC should be considered when recommending screening and treatment. Further research is needed to inform age-specific treatment guidelines.

Identification of Moesin (MSN) as a Potential Therapeutic Target for Colorectal Cancer via the β-Catenin-RUNX2 Axis

CRC is the second leading cause of cancer-related death. The complex mechanisms of metastatic CRC limit available therapeutic choice. Thus, identifying new CRC therapeutic targets is essential. Moesin (MSN), a member of the ezrin-radixin-moesin family, connects the cell membrane to the actin-based cytoskeleton and regulates cell morphology. We investigated the role of MSN in the progression of CRC. GENT2 and oncomine were used to study MSN expression and CRC patient outcomes. MSN-specific shRNAs or MSN-overexpressed plasmid were used to establish MSN-KD and MSN overexpressed cell lines, respectively. SRB, migration, wound healing, and flow cytometry were used to test cell survival and migration. Propidium iodide and annexin V stain were used to analyze the cell cycle and apoptosis. MSN expression was found to be higher in CRC tissues than in normal tissues. Higher MSN expression is associated with poor overall survival, disease-free survival, and relapse-free survival rates in CRC patients. MSN silencing inhibits cell proliferation, adhesion, migration, and invasion in vitro, whereas MSN overexpression accelerates cell proliferation, adhesion, migration, and invasion. RNA sequencing was used to investigate differentially expressed genes, and RUNX2 was discovered as a possible downstream target for MSN. In CRC patients, RUNX2 expression was significantly correlated with MSN expression. We also found that MSN silencing decreased cytoplasmic and nuclear β-catenin levels. Additionally, pharmacological inhibition of β-catenin in MSN-overexpressed cells led to a reduction of RUNX2, and activating β-catenin signaling by inhibiting GSK3β rescued the RUNX2 downregulation in MSN-KD cells. This confirms that MSN regulates RUNX2 expression via activation of β-catenin signaling. Finally, our result further determined that RUNX2 silencing reduced the ability of MSN overexpression cells to proliferate and migrate. MSN accelerated CRC progression via the β-catenin-RUNX2 axis. As a result, MSN holds the potential to become a new target for CRC treatment.

2,3,5,4'-Tetrahydroxystilbene (TG1), a Novel Compound Derived from 2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-glucoside (THSG), Inhibits Colorectal Cancer Progression by Inducing Ferroptosis, Apoptosis, and Autophagy

BACKGROUND

Colorectal cancer (CRC) is one of the deadliest cancers worldwide and long-term survival is not guaranteed in metastatic disease despite current multidisciplinary therapies. A new compound 2,3,5,4'-Tetrahydroxystilbene (TG1), derived from THSG (2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-Glucoside), has been developed, and its anticancer ability against CRC is verified in this study.

METHODS

HCT116, HT-29, and DLD-1 were treated with TG1 and the IC₅₀ was measured using a sulforhodamine B assay. A Xenograft mouse model was used to monitor tumor growth. Apoptosis and autophagy, induced by TG1 in CRC cells, were examined. RNA-sequencing analysis of CRC cells treated with TG1 was performed to discover underlying pathways and mechanisms.

RESULTS

The results demonstrated that treatment with TG1 inhibited CRC proliferation in vitro and in vivo and induced apoptotic cell death, which was confirmed by Annexin V-FITC/PI staining and Western blotting. Additionally, TG1 treatment increased the level of autophagy in cells. RNA-sequencing and GSEA analyses revealed that TG1 was associated with MYC and the induction of ferroptosis. Furthermore, the ferroptosis inhibitor Bardoxolone abrogated the cytotoxic effect of TG1 in CRC cells, indicating that ferroptosis played a crucial role in TG1-induced cytotoxicity.

CONCLUSIONS

These findings suggest that TG1 might be a potential and potent compound for clinical use in the treatment of CRC by inhibiting proliferation and inducing ferroptosis through the MYC pathway.

A Multi-Omics Overview of Colorectal Cancer to Address Mechanisms of Disease, Metastasis, Patient Disparities and Outcomes

Human colorectal cancer (CRC) is one of the most common malignancies in men and women across the globe, albeit CRC incidence and mortality shows a substantial racial and ethnic disparity, with the highest burden in African American patients. Even with effective screening tools such as colonoscopy and diagnostic detection assays, CRC remains a substantial health burden. In addition, primary tumors located in the proximal (right) or distal (left) sides of the colorectum have been shown to be unique tumor types that require unique treatment schema. Distal metastases in the liver and other organ systems are the major causes of mortality in CRC patients. Characterizing genomic, epigenomic, transcriptomic and proteomic (multi-omics) alterations has led to a better understanding of primary tumor biology, resulting in targeted therapeutic advancements. In this regard, molecular-based CRC subgroups have been developed that show correlations with patient outcomes. Molecular characterization of CRC metastases has highlighted similarities and differences between metastases and primary tumors; however, our understanding as to how to improve patient outcomes based on metastasis biology is lagging and remains a major obstacle to improving CRC patient outcomes. In this review, we will summarize the multi-omics features of primary CRC tumors and their metastases across racial and ethnic groups, the differences in proximal and distal tumor biology, molecular-based CRC subgroups, treatment strategies and challenges for improving patient outcomes.

Advanced statistics identification of participant and treatment predictors associated with severe adverse effects induced by fluoropyrimidine-based chemotherapy

PURPOSE

Adverse effects following fluoropyrimidine-based chemotherapy regimens are common. However, there are no current accepted diagnostic markers for prediction prior to treatment, and the underlying mechanisms remain unclear. This study aimed to determine genetic and non-genetic predictors of adverse effects.

METHODS

Genomic DNA was analyzed for 25 single nucleotide polymorphisms (SNPs). Demographics, comorbidities, cancer and fluoropyrimidine-based chemotherapy regimen types, and adverse effect data were obtained from clinical records for 155 Australian White participants. Associations were determined by bivariate analysis, logistic regression modeling and Bayesian network analysis.

RESULTS

Twelve different adverse effects were observed in the participants, the most common severe adverse effect was diarrhea (12.9%). Bivariate analysis revealed associations between all adverse effects except neutropenia, between genetic and non-genetic predictors, and between 8 genetic and 12 non-genetic predictors with more than 1 adverse effect. Logistic regression modeling of adverse effects revealed a greater/sole role for six genetic predictors in overall gastrointestinal toxicity, nausea and/or vomiting, constipation, and neutropenia, and for nine non-genetic predictors in diarrhea, mucositis, neuropathy, generalized pain, hand-foot syndrome, skin toxicity, cardiotoxicity and fatigue. The Bayesian network analysis revealed less directly associated predictors (one genetic and six non-genetic) with adverse effects and confirmed associations between six adverse effects, eight genetic predictors and nine non-genetic predictors.

CONCLUSION

This study is the first to link both genetic and non-genetic predictors with adverse effects following fluoropyrimidine-based chemotherapy. Collectively, we report a wealth of information that warrants further investigation to elucidate the clinical significance, especially associations with genetic predictors and adverse effects.

Treatment and Survival Outcomes for Patients with Colorectal Peritoneal Metastases Deemed Ineligible for Cytoreductive Surgery (CRS) with Hyperthermic Intraperitoneal Chemotherapy (HIPEC): Results of a Retrospective Study

BACKGROUND

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment option for selected patients with colorectal peritoneal metastases (PM). This report provides an overview of treatment and survival outcomes for patients deemed ineligible for CRS-HIPEC.

METHODS

Colorectal PM patients referred to a tertiary center from 2014 to 2020 that were ineligible for CRS-HIPEC were included. Patient, tumor, and treatment characteristics were provided. Survival analyses were performed using the Kaplan-Meier method.

RESULTS

Of 476 patients referred for CRS-HIPEC, 227 (48%) were deemed ineligible. Median follow-up was 15 months [IQR 10-22]. Data on follow-up treatment was available for 198 patients, of which 73% received systemic therapy. These patients had a median overall survival (OS) of 17 months [IQR 9-25]. For patients receiving best supportive care (BSC) median OS was 4 months [IQR 2-9]. The main reason for ineligibility was extensive PM (42%), with a median OS of 11 months [IQR 5-18]. Patients deemed ineligible due to (extensive) liver (9%) or lung metastases (8%) showed longer OS (median 22 months, IQR 8-27, and 24 months, IQR 12-29, respectively) than patients with extensive PM (median 11 months, IQR 5-18) or distant lymph node metastases (median 14 months, IQR 4-25).

CONCLUSION

The main reason for CRS-HIPEC ineligibility was extensive PM. The majority of patients received systemic therapy. Patients deemed ineligible due to extra-peritoneal metastases had better survival outcomes than patients deemed ineligible due to extensive PM.

Treatment of Metastatic Colorectal Cancer: ASCO Guideline

PURPOSE

To develop recommendations for treatment of patients with metastatic colorectal cancer (mCRC).

METHODS

ASCO convened an Expert Panel to conduct a systematic review of relevant studies and develop recommendations for clinical practice.

RESULTS

Five systematic reviews and 10 randomized controlled trials met the systematic review inclusion criteria.

RECOMMENDATIONS

Doublet chemotherapy should be offered, or triplet therapy may be offered to patients with previously untreated, initially unresectable mCRC, on the basis of included studies of chemotherapy in combination with anti-vascular endothelial growth factor antibodies. In the first-line setting, pembrolizumab is recommended for patients with mCRC and microsatellite instability-high or deficient mismatch repair tumors; chemotherapy and anti-epidermal growth factor receptor therapy is recommended for microsatellite stable or proficient mismatch repair left-sided treatment-naive RAS wild-type mCRC; chemotherapy and anti-vascular endothelial growth factor therapy is recommended for microsatellite stable or proficient mismatch repair RAS wild-type right-sided mCRC. Encorafenib plus cetuximab is recommended for patients with previously treated BRAF V600E-mutant mCRC that has progressed after at least one previous line of therapy. Cytoreductive surgery plus systemic chemotherapy may be recommended for selected patients with colorectal peritoneal metastases; however, the addition of hyperthermic intraperitoneal chemotherapy is not recommended. Stereotactic body radiation therapy may be recommended following systemic therapy for patients with oligometastases of the liver who are not considered candidates for resection. Selective internal radiation therapy is not routinely recommended for patients with unilobar or bilobar metastases of the liver. Perioperative chemotherapy or surgery alone should be offered to patients with mCRC who are candidates for potentially curative resection of liver metastases. Multidisciplinary team management and shared decision making are recommended. Qualifying statements with further details related to implementation of guideline recommendations are also included.Additional information is available at www.asco.org/gastrointestinal-cancer-guidelines.

Oncotherapeutic Strategies in Early Onset Colorectal Cancer

Early onset colorectal cancer (EOCRC), defined as colorectal cancers in patients aged less than 50 years, is becoming an increasingly common issue, globally. Since 1994, the incidence of this condition has been rising by 2% annually. Approximately one in five patients under 50 years of age diagnosed with colorectal cancer have an underlying genetic predisposition syndrome. The detection of cancer among the other 80% of patients poses a considerable task, as there is no family history to advocate for commencing early screening in this group. Patients with EOCRC have distinct social, spiritual, fertility, and financial needs from their older counterparts that need to be addressed. This review discusses the risk factors associated with the development of EOCRC and current best practice for the management of this disease.

Current Targeted Therapy for Metastatic Colorectal Cancer

Colorectal cancer (CRC) is the third most common type of cancer and the second leading cause of cancer deaths worldwide. Surgery or surgery plus radiotherapy and/or chemotherapy for patients with metastatic CRC (mCRC) were accepted as the main therapeutic strategies until the early 2000s, when targeted drugs, like cetuximab and bevacizumab, were developed. The use of targeted drugs in clinical practice has significantly increased patients' overall survival. To date, the emergence of several types of targeted drugs has opened new possibilities and revealed new prospects for mCRC treatment. Therapeutic strategies are continually being updated to select the most suitable targeted drugs based on the results of clinical trials that are currently underway. This review discusses the up-to date molecular evidence of targeted therapy for mCRC and summarizes the Food and Drug Administration-approved targeted drugs including the results of clinical trials. We also explain their mechanisms of action and how these affect the choice of a suitable targeted therapy.

The optimal first-line treatment for patients with left-sided RAS wild-type metastatic colorectal cancer: Double-drug regimen or triple-drug regimen therapy

There are many treatments for metastatic colorectal cancer (mCRC). Among them, uncertainty remains especially concerning the clinical benefit of different regimens for left-sided RAS wild-type (WT) mCRC in the triple-drug therapy era. No studies have been conducted to answer this critical clinical issue. We performed a comprehensive analysis of published data and real-world data. First, we conducted analyses of the published trials to show the landscape of efficacy and safety in the treatments of left-sided RAS WT mCRC. Then, we initiated a multicenter real-world study as the validation dataset. This study included six published randomized controlled trials (RCTs) and a total of 1925 patients. The double-drug regimen plus cetuximab/panitumumab (D + C/P) achieved the longest overall survival (OS) in patients with left-sided mCRC (HR = 0.74, 95%CI: 0.57–0.98), while triple-drug regimen with bevacizumab (T + B, HR = 1.1, 95%CI: 0.63–2.0), compared with double-drug with bevacizumab (D + B). The D + C/P had the highest overall response rate (ORR) in patients with left-sided mCRC (OR = 1.8, 95%CI: 0.89–3.8), while T + B (OR = 1.8, 95%CI: 0.70–4.8), compared with D + B. The multicenter real-world cohort showed the double-drug regimen plus cetuximab had longer progression-free survival (PFS) in left-sided mCRC patients than the triple-drug regimen with bevacizumab. The safety analysis showed the incidence of the adverse events (grade≥3) in the triple-drug therapy plus bevacizumab was higher than that in the double-drug therapy plus cetuximab/panitumumab. This work demonstrates the ranking of three regimens for therapeutic efficacy and safety in patients with left-sided RAS WT mCRC. The double-drug regimen plus cetuximab/panitumumab appears more effective and safer than double-drug and triple-drug based regimens with bevacizumab. Further trials and cohort analyses on this topic would increase confidence in these results.

Metformin suppresses the growth of colorectal cancer by targeting INHBA to inhibit TGF-β/PI3K/AKT signaling transduction

Multiple evidence shows that metformin serves as a potential agent for Colorectal Cancer (CRC) treatment, while its molecular mechanisms still require detailed investigation. Here, we revealed that metformin specifically suppressed the proliferation of CRC cells by causing G1/S arrest, and INHBA is a potential target for metformin to play an anti-proliferation effect in CRC. We verified the oncogene role of INHBA by knocking down and overexpressing INHBA in CRC cells. Silencing INHBA abrogated the cell growth, while overexpression INHBA promotes the proliferation of CRC cells. As an oncogene, INHBA was aberrant overexpression in CRC tissues and closely related to the poor prognosis of CRC patients. In mechanism, INHBA is an important ligand of TGF-β signaling and metformin blocked the activation of TGF-β signaling by targeting INHBA, and then down-regulated the activity of PI3K/Akt pathway, leading to the reduction of cyclinD1 and cell cycle arrest. Together, these findings indicate that metformin down-regulates the expression of INHBA, then attenuating TGF-β/PI3K/Akt signaling transduction, thus inhibiting the proliferation of CRC. Our study elucidated a novel molecular mechanism for the anti-proliferation effect of metformin, providing a theoretical basis for the application of metformin in CRC therapy.

Application of Tumor Burden Score for predicting conversion outcome in patients with initially unresectable colorectal liver metastases after first-line systemic therapy

BACKGROUND

Patients with initially unresectable colorectal liver metastases (CRLM) could achieve survival benefit from successful conversion therapy. Recently, Tumor Burden Score (TBS) was proposed as a valuable index to predict outcome following resection of CRLM. The study is aimed to investigate the association of TBS with conversion outcome.

METHODS

A total of 234 patients who underwent first-line treatment in our center were enrolled as training cohort. The validation cohort was developed from 89 patients in our previous study. Cut-off value of TBS was calculated to stratify patients into two groups. Significance test and logistic regression model were used to examine the prediction value of TBS for conversion outcome after first-line systemic therapy. Kaplan-Meier method and Cox proportional hazard model were applied to assess the prognostic value of TBS.

RESULTS

TBS showed good discriminatory power [area under curve (AUC) 0.726, p < 0.001] with cut-off value defined as 14.3 in training cohort, which was validated in the validation cohort. Increasing TBS was related to adverse chemotherapy response and conversion outcome. Low TBS group had three times higher conversion rate than that in high TBS group (57.3% versus 19.0%, p < 0.001). Multivariate analysis indicated that high TBS [odds ratio (OR) = 3.676, 95% confidence interval (CI) 1.671-8.429, p = 0.002], first-line treatment response as stable disease (SD) or progressive disease (PD) (OR = 9.247; 95% CI 4.736-18.846, p < 0.001), and absence of targeted therapy (OR = 2.453, 95% CI 1.139-5.455, p = 0.024) were three independent risk factors for failure conversion outcome. High TBS was significantly associated with conversion outcome whatever chemotherapy response, addition of targeted therapy, and Kirsten rat sarcoma viral oncogene homolog (KRAS) status. High TBS was also associated with worse overall survival.

CONCLUSION

TBS should be applied in clinical practice to predict conversion outcome in patients with initially unresectable CRLM.

Triplet chemotherapy in combination with anti-EGFR agents for the treatment of metastatic colorectal cancer: Current evidence, advances, and future perspectives

Doublet or triplet chemotherapy regimens in combination with anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies (mAb), such as cetuximab or panitumumab, or the anti-vascular endothelial growth factor mAb bevacizumab, are the current recommended standard of care therapies for unresectable metastatic colorectal cancer (mCRC). While the recommended dosing schedule for the triplet chemotherapy regimen with 5-fluorouracil, oxaliplatin and irinotecan (FOLFOXIRI) in combination with bevacizumab is well established, the optimal dosing of FOLFOXIRI in combination with anti-EGFR agents is unknown. Several randomized, phase 3 clinical trials of patients with mCRC have demonstrated improved survival and response rates with FOLFOXIRI, alone or when combined with bevacizumab, compared with doublet chemotherapy regimens. Trials of anti-EGFR agents in combination with FOLFOXIRI have also shown promising results. In this review, we summarize the emerging evidence regarding the safety and efficacy of anti-EGFR agents in combination with triplet chemotherapy regimens and discuss the potential for this combination as a future treatment option for patients with RAS-wild-type mCRC.

Molecular Determinants and Other Factors to Guide Selection of Patients for Hepatic Resection of Metastatic Colorectal Cancer

OPINION STATEMENT

Treatment for metastatic colorectal cancer (CRC) has changed significantly over the last few decades as cytotoxic and targeted chemotherapies have evolved and resection of (technically feasible) colorectal liver metastases (CRLM) has become standard of care for eligible patients. Overall, survival for metastatic CRC has considerably improved, but recurrences are common. Numerous clinical risk scores have been suggested to guide patient selection for CRLM resection, but none perfectly predict outcomes; therefore, a personalized approach to metastatic CRC treatment using genetic profiles for risk stratification and prognostication is a critically important advancement. All patients with suspected metastatic CRC should undergo genetic testing for common oncogene mutations (e.g., KRAS, BRAF, and NRAS) in addition to a triphasic CT scan of the chest, abdomen, and pelvis; if hepatectomy may be entertained and there is concern about the future liver remnant (FLR), liver volumetrics should also be performed. MRI and PET are useful adjuncts for cases in which diagnosis or extent of disease is unclear. The decision to operate should be individualized and based on each patient's condition, tumor biology, and technical resectability. Genetic profiles should be used to inform multidisciplinary meetings surrounding topics of chemotherapy and surgical resection, as well as patient discussions concerning the risks and benefits of surgery. In the end, most patients with technically resectable colorectal cancers and adequate cardiopulmonary fitness benefit from surgical resection, as it remains the only chance of long-term survival.

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.

Telomere maintenance in interplay with DNA repair in pathogenesis and treatment of colorectal cancer

Colorectal cancer (CRC) continues to be one of the leading malignancies and causes of tumour-related deaths worldwide. Both impaired DNA repair mechanisms and disrupted telomere length homeostasis represent key culprits in CRC initiation, progression and prognosis. Mechanistically, altered DNA repair results in the accumulation of mutations in the genome and, ultimately, in genomic instability. DNA repair also determines the response to chemotherapeutics in CRC treatment, suggesting its utilisation in the prediction of therapy response and individual approach to patients. Telomere attrition resulting in replicative senescence, simultaneously by-passing cell cycle checkpoints, is a hallmark of malignant transformation of the cell. Telomerase is almost ubiquitous in advanced solid cancers, including CRC, and its expression is fundamental to cell immortalisation. Therefore, there is a persistent effort to develop therapeutics, which are telomerase-specific and gentle to non-malignant tissues. However, in practice, we are still at the level of clinical trials. The current state of knowledge and the route, which the research takes, gives us a positive perspective that the problem of molecular models of telomerase activation and telomere length stabilisation will finally be solved. We summarise the current literature herein, by pointing out the crosstalk between proteins involved in DNA repair and telomere length homeostasis in relation to CRC.

Metastatic Colorectal Cancer. First Line Therapy for Unresectable Disease

Colorectal cancer (CRC) is a commonly diagnosed malignancy. The prognosis of patients with unresectable, metastatic colorectal cancer (mCRC) is dismal and medical treatment is mainly palliative in nature. Although chemotherapy remains the backbone of treatment, the landscape is changing with the understanding of its heterogeneity and molecular biology. First-line therapy relies on a combination of chemotherapy and targeted therapies, according to clinical patient characteristics and tumor molecular profile. Here we review current evidence from randomized clinical trials for using chemotherapy doublets or triplets, and for the addition of bevacizumab or anti-epidermal growth factor receptor (EGFR) agents. Novel therapies developed for small, selected populations are also discussed.

Association of 5-FU Therapeutic Drug Monitoring to DPD Phenotype Assessment May Reduce 5-FU Under-Exposure

In order to limit 5-fluorouracil (5-FU) toxicity, some health agencies recommend evaluating dihydropyrimidine dehydrogenase (DPD) deficiency before any 5-FU treatment introduction. In our study, we investigated relationships between 5-FU clearance and markers of DPD activity such as uracilemia (U), dihydrouracilemia (UH₂)/U ratio, or genotype of the gene encoding DPD (DPYD). All patients with gastrointestinal cancers who received 5-FU-based regimens form March 2018 to June 2020 were included in our study. They routinely benefited of a pre-therapeutic DPYD genotyping and phenotyping. During 5-FU infusion, blood samples were collected to measure 5-FU steady-state concentration in order to adapt 5-FU doses at the following cycles. A total of 169 patients were included. Median age was 68 (40–88) years and main primary tumor sites were colorectal (40.8%) and pancreas (31.4%), metastatic in 76.3%. 5-FU was given as part of FOLFIRINOX (44.4%), simplified FOLFOX-6 (26.6%), or docetaxel/FOLFOX-4 (10.6%). Regarding DPD activity, median U and UH₂/U were, respectively, 10.8 ng/mL and 10.1, and almost 15% harbored a heterozygous mutation. On the range of measured U and UH₂/U, no correlation was observed with 5-FU clearance. Moreover, in patients with U < 16 ng/mL, 5-FU exposure was higher than in other patients, and most of them benefited of dose increase following 5-FU therapeutic drug monitoring (TDM). If recent guidelines recommend decreasing 5-FU dose in patients harboring U ≥ 16 ng/mL, our study highlights that those patients are at risk of under-exposure and that 5-FU TDM should be conducted in order to avoid loss of efficacy.

Rapid screening for individualized chemotherapy optimization of colorectal cancer: A novel conditional reprogramming technology-based functional diagnostic assay

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Established a new in vitro tumor model called novel conditionally reprogrammed (termed i-CR).

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Accomplished personalized drug tests within 2–3 weeks.

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Achieved 100% sensitivity, 85.7% specificity, 91.7% positive predictive value, and 100% negative predictive value.

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i-CR guided a inoperable patient with metastases converted to radical surgery.

Background

In vitro patient tumor models such as patient-derived organoids (PDO) and conditionally reprogrammed (CR) cell culture are important for translational research and pre-clinical drug testing. In this study we present a personalized drug sensitivity test for late stage, potentially operable colorectal cancer (CRC) using patient-derived primary tumor cells isolated with i-CR technology, an optimized CR method. We explored the clinical feasibility of using i-CR platform to guide CRC chemotherapy, and established the correlation between in vitro drug sensitivity and patient clinical response.

Methods

Primary CRC tumor cells were isolated and cultured with the i-CR technology. NGS was performed and the WES and CNV results of i-CR cells were compared with that of the original patient tumor samples. In vitro drug screenings were done with guideline chemotherapy drugs for CRC. In vivo drug response was examined with paired PDX mouse models. A double-blind co-clinical cohort study was carried out and the clinical outcomes of the enrolled patients were compared with the i-CR results.

Results

i-CR platform could be used to rapidly propagate primary colorectal tumor cells that represent individual patient tumors effectively by keeping the clonal heterogeneity and the genetic characteristics. Chemotherapy drug screenings with i-CR cells were comparable with that of PDX models. More importantly, i-CR results showed high accordance with the clinical outcomes of the enrolled CRC patients.

Conclusion

i-CR platform was capable to test and optimize therapeutic regimens pre-clinically, study cancer cell biology, and model tumor re-emergence to identify new targeted therapeutics from an effective personalized medicine standpoint.

Colorectal liver metastases: Current management and future perspectives

The liver is the commonest site of metastatic disease for patients with colorectal cancer, with at least 25% developing colorectal liver metastases (CRLM) during the course of their illness. The management of CRLM has evolved into a complex field requiring input from experienced members of a multi-disciplinary team involving radiology (cross sectional, nuclear medicine and interventional), Oncology, Liver surgery, Colorectal surgery, and Histopathology. Patient management is based on assessment of sophisticated clinical, radiological and biomarker information. Despite incomplete evidence in this very heterogeneous patient group, maximising resection of CRLM using all available techniques remains a key objective and provides the best chance of long-term survival and cure. To this end, liver resection is maximised by the use of downsizing chemotherapy, optimisation of liver remnant by portal vein embolization, associating liver partition and portal vein ligation for staged hepatectomy, and combining resection with ablation, in the context of improvements in the functional assessment of the future remnant liver. Liver resection may safely be carried out laparoscopically or open, and synchronously with, or before, colorectal surgery in selected patients. For unresectable patients, treatment options including systemic chemotherapy, targeted biological agents, intra-arterial infusion or bead delivered chemotherapy, tumour ablation, stereotactic radiotherapy, and selective internal radiotherapy contribute to improve survival and may convert initially unresectable patients to operability. Currently evolving areas include biomarker characterisation of tumours, the development of novel systemic agents targeting specific oncogenic pathways, and the potential re-emergence of radical surgical options such as liver transplantation.

Chemotherapy With or Without Anti-EGFR Agents in Left- and Right-Sided Metastatic Colorectal Cancer: An Updated Meta-Analysis

BACKGROUND

Previous meta-analyses have suggested primary tumor location as a predictive factor for efficacy of anti-epidermal growth factor receptor (EGFR) therapies in patients with metastatic colorectal cancer (mCRC). However, the recent phase III TAILOR trial addressing this issue was not included in those analyses. This meta-analysis incorporated data from the TAILOR trial to evaluate the efficacy of chemotherapy plus anti-EGFR agents (cetuximab [Cet] or panitumumab [Pani]) versus chemotherapy alone for RAS wild-type (wt) right- and left-sided mCRC.

PATIENTS AND METHODS

A PubMed-based literature search was conducted to identify randomized controlled trials (RCTs) studying the additional efficacy of Cet/Pani in combination with chemotherapy versus chemotherapy alone in RAS wt left- and right-sided mCRC. Study-level pooled analyses of hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) and odds ratios (ORs) for objective response rate (ORR) were performed.

RESULTS

Three first-line RCTs (CRYSTAL, PRIME, and TAILOR) and one second-line RCT (20050181) were included. Significant OS benefits from Cet/Pani were observed in the left-sided (HR, 0.76; 95% CI, 0.66-0.86) but not right-sided subgroups (HR, 0.99; 95% CI, 0.78-1.27). However, the addition of Cet/Pani to chemotherapy significantly improved PFS and ORR in both the left-sided (HR, 0.70; 95% CI, 0.57-0.86, and OR, 3.28; 95% CI, 1.95-5.51, respectively) and right-sided subgroups (HR, 0.76; 95% CI, 0.59-0.99, and OR, 1.78; 95% CI, 1.08-2.93, respectively).

CONCLUSIONS

The addition of Cet/Pani to chemotherapy significantly benefits PFS and ORR in patients with RAS wt right-sided mCRC, indicating that anti-EGFR therapies may remain an option for selected patients.

5-Fluorouracil Response Prediction and Blood Level-Guided Therapy in Oncology: Existing Evidence Fundamentally Supports Instigation

5-Fluorouracil (5-FU) response prediction and therapeutic drug monitoring (TDM) are required to minimize toxicity while preserving efficacy. Conventional 5-FU dose normalization uses body surface area. It is characterized by up to 100-fold interindividual variability of pharmacokinetic (PK) parameters, and typically >50% of patients have plasma 5-FU concentrations outside the optimal range. This underscores the need for a different dose rationalization paradigm, hence there is a case for 5-FU TDM. An association between 5-FU PK parameters and efficacy/toxicity has been established. It is believed that 5-FU response is enhanced and toxicity is reduced by PK management of its dosing. The area under the concentration-time curve is the most relevant PK parameter associated with 5-FU efficacy/toxicity, and optimal therapeutic windows have been proposed. Currently, there is no universally applied a priori test for predicting 5-FU response and identifying individuals with an elevated risk of toxicity. The following two-step strategy: prediction of response/toxicity and TDM for subsequent doses seems plausible. Approximately 80% of 5-FU is degraded in a three-step sequential metabolic pathway. Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme. Its deficiency can cause toxicity with standard 5-FU doses. DPD also metabolizes uracil (U) into 5,6-dihydrouracil (UH2). The UH2/U ratio is an index of DPD activity and a credible biomarker of response and toxicity. This article outlines the UH2/U ratio as a parameter for 5-FU response/toxicity prediction and highlights key studies emphasizing the value of 5-FU TDM. Broad application of 5-FU response/toxicity prediction and blood level-guided therapy remains unmet, despite ever-increasing clinical interest. Considered collectively, existing evidence is compelling and fundamentally supports universal instigation of response/toxicity prediction and TDM.

Clinical utility of polyethylene glycol conjugated granulocyte colony-stimulating factor (PEG-G-CSF) for preventing severe neutropenia in metastatic colorectal cancer patients treated with FOLFOXIRI plus bevacizumab: a single-center retrospective study

Background

This study aimed to evaluate the efficacy and the safety of polyethylene glycol conjugated granulocyte colony-stimulating factor (PEG-G-CSF) for preventing neutropenia in metastatic colorectal cancer (mCRC) patients that received fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI) plus bevacizumab (Bev) in clinical practice.

Methods

We retrospectively analyzed mCRC patients who received FOLFOXIRI plus Bev between December 2015 and December 2017. We evaluated the efficacy of PEG-G-CSF as preventing or treating grade 3 or 4 neutropenia, the overall response rate (ORR) according to the Response Evaluation Criteria in Solid Tumors version 1.1, progression-free survival (PFS), overall survival (OS), and adverse events of FOLFOXIRI plus Bev based on the Common Terminology Criteria for Adverse Events version 4.0.

Results

A total of 26 patients (median age 53.5 years) were included. The ORR rate was 65.3%, the median PFS was 9.6 months (7.2–16.9), and the median OS was 24.2 months (13.6–NA). Grade 3 or 4 neutropenia occurred in 53.8% of the patients, and febrile neutropenia occurred in 7.7%. PEG-G-CSF was given to 77.0% of the patients, including prophylactically (n = 9) and after the development of grade 3 or 4 neutropenia (n = 11). No patients experienced grade 3 or 4 neutropenia after the administration of PEG-G-CSF. In seven of the nine patients who received PEG-G-CSF prophylactically (77.8%), no dose adjustment was required.

Conclusions

PEG-G-CSF is useful in preventing severe neutropenia in mCRC patients treated with FOLFOXIRI plus Bev.

Sex-dependent least toxic timing of irinotecan combined with chronomodulated chemotherapy for metastatic colorectal cancer: Randomized multicenter EORTC 05011 trial

The least toxic time (LTT) of irinotecan varied by up to 8 hours according to sex and genetic background in mice. The translational relevance was investigated within a randomized trial dataset, where no LTT stood out significantly in the whole population. 130 male and 63 female eligible patients with metastatic colorectal cancer were randomized to receive chronomodulated Irinotecan with peak delivery rate at 1 of 6 clock hours staggered by 4 hours on day 1, then fixed-time chronomodulated Fluorouracil-Leucovorin-Oxaliplatin for 4 days, q3 weeks. The sex-specific circadian characteristics of grade (G) 3-4 toxicities were mapped with cosinor and time*sex interactions confirmed with Fisher's exact test. Baseline characteristics of male or female patients were similar in the six treatment groups. Main grade 3-4 toxicities over six courses were diarrhea (males vs females, 39.2%; vs 46.0%), neutropenia (15.6% vs 15.0%), fatigue (11.5% vs 15.9%), and anorexia (10.0% vs 7.8%). They were reduced following irinotecan peak delivery in the morning for males, but in the afternoon for females, with statistically significant rhythms (P < .05 from cosinor) and sex*timing interactions (Fisher's exact test, diarrhea, P = .023; neutropenia, P = .015; fatigue, P = .062; anorexia, P = .032). Irinotecan timing was most critical for females, with grades 3-4 ranging from 55.2% of the patients (morning) to 29.4% (afternoon) for diarrhea, and from 25.9% (morning) to 0% (afternoon) for neutropenia. The study results support irinotecan administration in the morning for males and in the afternoon for females, in order to minimize adverse events without impairing efficacy.

A Model of a Zebrafish Avatar for Co-Clinical Trials

Animal “avatars” and co-clinical trials are being developed for possible use in personalized medicine in oncology. In a co-clinical trial, the cancer cells of the patient’s tumor are xenotransplanted into the animal avatar for drug efficacy studies, and the data collected in the animal trial are used to plan the best drug treatment in the patient trial. Zebrafish have recently been proposed for implementing avatar models, however the lack of a general criterion for the chemotherapy dose conversion from humans to fish is a limitation in terms of conducting co-clinical trials. Here, we validate a simple, reliant and cost-effective avatar model based on the use of zebrafish embryos. By crossing data from safety and efficacy studies, we found a basic formula for estimating the equivalent dose for use in co-clinical trials which we validated in a clinical study enrolling 24 adult patients with solid cancers (XenoZ, NCT03668418).

Design and synthesis of new energy restriction mimetic agents: Potent anti-tumor activities of hybrid motifs of aminothiazoles and coumarins

The incidence of obesity-related diseases like diabetes, cardiovascular diseases, and different types of cancers shed light on the importance of dietary control as preventive and treatment measures. However, long-term dietary control is challenging to achieve in most individuals. The use of energy restriction mimetic agents (ERMAs) as an alternative approach to affect the energy machinery of cancer cells has emerged as a promising approach for cancer therapy. ERMAs limit the high need for energy in rapidly growing tumor cells, with their survival rate strongly dependent on the robust availability of energy. In this context, initial phenotypic screening of an in-house pilot compound library identified a new class of aminothiazole anchored on coumarin scaffold as potent anticancer lead drug candidates with potential activity as ERMA. The identified chemotypes were able to inhibit glucose uptake and increase ROS content in cancer cells. Compounds 9b, 9c, 9i, 11b, and 11c were highly active against colorectal cancer cell lines, HCT116 and HT-29, with half-maximal inhibitory concertation (IC₅₀) range from 0.25 to 0.38 µM. Further biological evaluations of 9b and 9f using Western blotting, caspase activity, glucose uptake, ROS production, and NADPH/NADP levels revealed the ability of these lead drug candidates to induce cancer cell death via, at least in part, energy restriction. Moreover, the assessment of 9b and 9f synergistic activity with cisplatin showed promising outcomes. The current work highlights the significant potential of the lead compounds, 9b, and 9f as potential anticancer agents via targeting the cellular energy machinery in cancer cells.

Chimeric Antigen Receptor T-Cell Therapy for Colorectal Cancer

Chimeric antigen receptor (CAR) T-cell therapy represents a new genetically engineered method of immunotherapy for cancer. The patient’s T-cells are modified to express a specific receptor that sticks to the tumor antigen. This modified cell is then reintroduced into the patient’s body to fight the resilient cancer cells. After exhibiting positive results in hematological malignancies, this therapy is being proposed for solid tumors like colorectal cancer. The clinical data of CAR T-cell therapy in colorectal cancer is rather scarce. In this review, we summarize the current state of knowledge, challenges, and future perspectives of CAR T-cell therapy in colorectal cancer. A total of 22 articles were included in this review. Eligible studies were selected and reviewed by two researchers from 49 articles found on Pubmed, Web of Science, and clinicaltrials.gov. This therapy, at the moment, provides modest benefits in solid tumors. Not taking into consideration the high manufacturing and retail prices, there are still limitations like increased toxicities, relapses, and unfavorable tumor microenvironment for CAR T-cell therapy in colorectal cancer.

Chemotherapy-induced peripheral neuropathy-part 2: focus on the prevention of oxaliplatin-induced neurotoxicity

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is regarded as one of the most common dose-limiting adverse effects of several chemotherapeutic agents, such as platinum derivatives (oxaliplatin and cisplatin), taxanes, vinca alkaloids and bortezomib. CIPN affects more than 60% of patients receiving anticancer therapy and although it is a nonfatal condition, it significantly worsens patients' quality of life. The number of analgesic drugs used to relieve pain symptoms in CIPN is very limited and their efficacy in CIPN is significantly lower than that observed in other neuropathic pain types. Importantly, there are currently no recommended options for effective prevention of CIPN, and strong evidence for the utility and clinical efficacy of some previously tested preventive therapies is still limited.

METHODS

The present article is the second one in the two-part series of review articles focused on CIPN. It summarizes the most recent advances in the field of studies on CIPN caused by oxaliplatin, the third-generation platinum-based antitumor drug used to treat colorectal cancer. Pharmacological properties of oxaliplatin, genetic, molecular and clinical features of oxaliplatin-induced neuropathy are discussed.

RESULTS

Available therapies, as well as results from clinical trials assessing drug candidates for the prevention of oxaliplatin-induced neuropathy are summarized.

CONCLUSION

Emerging novel chemical structures-potential future preventative pharmacotherapies for CIPN caused by oxaliplatin are reported.

DNA repair capacity and response to treatment of colon cancer

DNA repair, a complex biological process, ensures genomic integrity. Alterations in DNA repair, occurring in many cancers, contribute to the accumulation of mutations in the genome, resulting in genomic instability and cancer progression. DNA repair also plays a substantial role in response to chemotherapeutics: rapidly dividing colon cancer cells, vulnerable to DNA-damaging agents and overcoming DNA repair, undergo cell death. DNA repair capacity represents a complex biomarker, integrating gene variants, gene expressions, the stability of gene products, the effect of inhibitors/stimulators, lifestyle and environmental factors. Here, we discuss DNA repair capacity in sporadic colon cancer, a frequent malignancy worldwide, in relation to tumor heterogeneity, prognosis and prediction, measurements in surrogate and target tissues and suggest important tasks to be addressed.

RNA sequencing reveals PNN and KCNQ1OT1 as predictive biomarkers of clinical outcome in stage III colorectal cancer patients treated with adjuvant chemotherapy

Five-year overall survival of stage III colorectal cancer (CRC) patients treated with standard adjuvant chemotherapy (ACHT) is highly variable. Genomic biomarkers and/or transcriptomic profiles identified lack of adequate validation. Aim of our study was to identify and validate molecular biomarkers predictive of ACHT response in stage III CRC patients by a transcriptomic approach. From a series of CRC patients who received ACHT, two stage III extreme cohorts (unfavorable vs. favorable prognosis) were selected. RNA-sequencing was performed from fresh frozen explants. Tumors were characterized for somatic mutations. Validation was performed in stage III CRC patients extracted from two GEO datasets. According to disease-free survival (DFS), 108 differentially expressed genes (104/4 up/downregulated in the unfavorable prognosis group) were identified. Among 104 upregulated genes, 42 belonged to olfactory signaling pathways, 62 were classified as pseudogenes (n = 17), uncharacterized noncoding RNA (n = 10), immune response genes (n = 4), microRNA (n = 1), cancer-related genes (n = 14) and cancer-unrelated genes (n = 16). Three out of four down-regulated genes were cancer-related. Mutational status (i.e., RAS, BRAF, PIK3CA) did not differ among the cohorts. In the validation cohort, multivariate analysis showed high PNN and KCNQ1OT1 expression predictive of shorter DFS in ACHT treated patients (p = 0.018 and p = 0.014, respectively); no difference was observed in untreated patients. This is the first study that identifies by a transcriptomic approach and validates PNN and KCNQ1OT1 as molecular biomarkers predictive of chemotherapy response in stage III CRC patients. After a further validation in an independent cohort, PNN and KCNQ1OT1 evaluation could be proposed to prospectively identify stage III CRC patients benefiting from ACHT.

Patient-reported outcomes and health-related quality of life for cetuximab versus bevacizumab in metastatic colorectal cancer: a prospective cohort study

PURPOSE

Uncertainty exists regarding Patient-Reported Outcomes (PROs) and Health-Related Quality of Life (HRQoL) of patients with metastatic colorectal cancer (mCRC) treated with cetuximab or bevacizumab. We conducted a prospective cohort study comparing PROs and HRQoL from both therapies.

METHODS

We assessed PROs and HRQoL from patients treated with cetuximab or bevacizumab using QLQ-C30 and QLQ-CR29 questionnaires at three sequential time points, including baseline. Global Health Status (GHS), functional and symptom scales, and Overall Treatment Utility (derived from clinical and patient-reported outcomes) were compared for the two treatment strategies.

RESULTS

Between January 2017 and April 2018, 44 patients were allocated to cetuximab (n = 19) or bevacizumab (n = 25). Except for RAS mutation status, patient baseline characteristics were generally well balanced across treatment groups. A higher proportion of patients experienced a deterioration in GHS (≥ 10%) in cetuximab arm - 53.8% (95% CI 25.1-80.8%) at 6 weeks and 66.7% (95% CI 29.9-92.5%) at 12 weeks-comparing to bevacizumab cohort: 18.2% (95% CI 5.2-40.3%) at 6 weeks and 12.5% (95% CI:1.6-38.3%) at 12 weeks. Treatment utility rates at 6 and 12 weeks were, respectively, 88.6% and 69.8% for bevacizumab, compared to 49% and 19.1% for cetuximab (p = 0.004), a difference confirmed in subset analyses.

CONCLUSIONS

In patients with mCRC, cetuximab-containing regimens led to a progressive negative impact on PROs and global HRQoL, when compared to baseline and bevacizumab. Future research is needed to confirm these results. Our findings demonstrate the value of PROs when assessing comparative effectiveness of different treatment regimens.

Phase I study of preoperative chemoradiotherapy with sequential oxaliplatin and irinotecan with S-1 for locally advanced rectal cancer

The present study designed a novel preoperative chemoradiotherapy (CRT) with sequential oxaliplatin and irinotecan with S-1 for locally advanced rectal cancer (LARC). This phase I study evaluated the maximum tolerated dose and recommended dose (RD) of oxaliplatin following irinotecan with S-1. Patients with clinical stage T3 or 4 or involvement of the regional nodes and no evidence of distant metastases were treated with fixed doses of S-1 (80 mg/m²/day) on days 1-5, 8-12, 15-19, 22-27 and 29-33, and irinotecan (40 mg/m²/day) on days 1 and 8, followed by oxaliplatin on days 22 and 29. The dose of oxaliplatin was initially 40 mg/m² (level 1) with a predefined dose escalation schedule. The radiation dose was 1.8 Gy/fraction to a total dose of 45 Gy. A total of 9 patients were enrolled in the present study and 7 patients completely received CRT with this study protocol. The maximum tolerated dose for oxaliplatin was 50 mg/m² (level 2). Three of four patients experienced dose-limiting toxicity (grade 3 diarrhea) in oxaliplatin phase of level 2 dose. The RD of oxaliplatin was 40 mg/m² (level 1 dose). In addition, 2 patients had pathological CR (28.5%). Novel preoperative CRT with sequential oxaliplatin and irinotecan with S-1 for LARC resulted in acceptable toxicity and promising efficacy. However, the RD of oxaliplatin was lower than in previous CRT studies that combined oxaliplatin with S-1. To administer higher oxaliplatin, we have planned a phase I trial of preoperative CRT with sequential oxaliplatin followed by irinotecan with S-1 for LARC.

Morphine in acute coronary syndrome: systematic review and meta-analysis

OBJECTIVE

Morphine is frequently used in acute coronary syndrome (ACS) due to its analgesic effect, it being recommended in the main cardiology guidelines in Europe and the USA. However, controversy exists regarding its routine use due to potential safety concerns. We conducted a systematic review of randomised-controlled trials (RCTs) and observational studies to synthesise the available evidence.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

CENTRAL, MEDLINE, EMBASE and trial registries.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included RCTs and observational studies evaluating the impact of morphine in cardiovascular outcomes or platelet reactivity measures.

DATA EXTRACTION AND SYNTHESIS

Data were screened, extracted and appraised by two independent reviewers. The data were pooled results using a random-effects model. Outcomes included in-hospital mortality, major adverse cardiovascular events (MACE), platelet reactivity (using VerifyNow) and bleeding, reported as relative risk (RR) with 95% CI. We assessed the confidence in the evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. We followed the Meta-analysis Of Observational Studies in Epidemiology and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Five RCTs and 12 observational studies were included, enrolling 69 993 participants. Pooled results showed an increased risk of in-hospital mortality (RR 1.45 [95% CI 1.10 to 1.91], low GRADE confidence), MACE (RR 1.21, 95% CI 1.02 to 1.45) and an increased platelet reactivity at 1 and 2 hours (59.37 platelet reactivity units [PRU], 95% CI 36.04 to 82.71; 68.28 PRU, 95% CI 37.01 to 99.55, high GRADE confidence) associated with morphine. We found no significant difference in the risk of bleeding. We found no differences in subgroup analyses based on study design and ACS subtype.

CONCLUSIONS

Morphine was associated with an increased risk of in-hospital mortality and MACE but the high risk of bias leads to low result confidence. There is high confidence that morphine decreases the antiplatelet effect of P2Y12 inhibitors.

PROSPERO REGISTRATION NUMBER

CRD42016036357.

MRN (MRE11-RAD50-NBS1) Complex in Human Cancer and Prognostic Implications in Colorectal Cancer

The MRE11-RAD50-NBS1 (MRN) complex has been studied in multiple cancers. The identification of MRN complex mutations in mismatch repair (MMR)-defective cancers has sparked interest in its role in colorectal cancer (CRC). To date, there is evidence indicating a relationship of MRN expression with reduced progression-free survival, although the significance of the MRN complex in the clinical setting remains controversial. In this review, we present an overview of the function of the MRN complex, its role in cancer progression, and current evidence in colorectal cancer. The evidence indicates that the MRN complex has potential utilisation as a biomarker and as a putative treatment target to improve outcomes of colorectal cancer.

Update on systemic therapy for colorectal cancer: biologics take sides

Over the last decade, progress in the management of metastatic colorectal cancer (CRC) has focused on the development of biologic therapy in addition to the back bone of combination chemotherapy. Anti-epidermal growth factor receptor (EGFR) antibodies and agents targeting angiogenesis are widely used in the clinic, and more recently, in a subset of patients with mismatch repair (MMR) deficient cancer, immunotherapy with immune check point inhibitors have been integrated into clinical practice. The major challenge with the use of these biologic therapies is determining predictive biomarkers to optimize patient selection. In this review, we discuss the most recent updates in the use of biologic therapy in CRC. We review data on the role of primary tumor location (PTL) (sidedness) as predictive biomarker and recent advances in treatment of CRC with BRAF mutation.

How can we best monitor 5-FU administration to maximize benefit to risk ratio?

INTRODUCTION

5-Fluorouracil (5-FU) is currently used as a chemotherapy in several cancers such as head-and-neck (H&N) and colorectal cancers. 5-FU dosing is traditionally based on body surface area (BSA), but this strategy is usually associated with severe toxicities. 5-FU is mainly catabolized by dihydropyrimidine dehydrogenase (DPD), and 5-FU dosage adaptation according to DPD status at the first cycle of treatment is now recommended. To further optimize 5-FU-based chemotherapy, a body of evidences justifies therapeutic drug monitoring (TDM). Areas covered: 5-FU pharmacokinetics, relationships between pharmacokinetics and efficacy or toxicity of 5-FU, proofs of interest of 5-FU TDM and its practical considerations are discussed. Expert opinion: BSA-adjusted 5-FU administration is associated with a large inter-individual variability, and according to this strategy, many patients experience under- or overexposure. Moreover, relationships between 5-FU area under the curve (AUC) and its toxicity or efficacy have been demonstrated, at least in patients with colorectal or H&N cancers. 5-FU therapeutic index has been validated and algorithms of 5-FU dosage adaptation according to its AUC are now available. Advances in pre-analytical and analytical steps of 5-FU TDM make its use feasible in clinical practice. Thus, there are consistent evidences to recommend 5-FU TDM in patients with advanced colorectal or H&N cancers.

[5-fluorouracil therapeutic drug monitoring: Update and recommendations of the STP-PT group of the SFPT and the GPCO-Unicancer]

Despite being 60-years old now, 5-FU remains the backbone of numerous regimen to treat a variety of solid tumors such as breast, head-and-neck and digestive cancers either in neo-adjuvant, adjuvant or metastatic settings. Standard 5-FU usually claims 15-40% of severe toxicities and up to 1% of toxic-death. Numerous studies show a stiff relationship between 5-FU exposure and toxicity or efficacy. In addition, 5-FU pharmacokinetics is highly variable between patients. Indeed, 80% of the 5-FU dose is catabolized in the liver by dihydropyrimidine dehydrogenase (DPD) into inactive compounds. It is now well established that DPD deficiency could lead to severe toxicities and, thus, require dose reduction in deficient patients. However, despite dosage adaptation based on DPD status, some patients may still experience under- or over-exposure, leading to inefficacy or major toxicity. The "Suivi thérapeutique pharmacologique et personnalisation des traitements" (STP-PT) group of the "Société française de pharmacologie et de thérapeutique" (SFPT) and the "Groupe de pharmacologie clinique oncologique" (GPCO)-Unicancer, based on the latest and most up-to-date literature data, recommend the implementation of 5-FU Therapeutic Drug Monitoring in order to ensure an adequate 5-FU exposure.

Chemosensitivity of various peritoneal cancer cell lines to HIPEC and PIPAC: comparison of an experimental duplex drug to standard drug regimens in vitro

We performed an in-vitro study testing the chemosensitivity of peritoneal cancer cell lines (SW620, HCT116, MKN45, 23,132/87, OAW42) to various cytostatic drug regimens. A duplex drug, characterized by reversible linking of the antimetabolites 2'-deoxy-5-fluorouridine (5-FdU) and 3'-C-ethynylcytidine (ECyd), was compared to oxaliplatin or to cisplatin plus doxorubicin. The experiments were designed to reflect the conditions of intraperitoneal chemotherapy. CASY® (Cell Analysis System) technology was used to compare the impact of incubation temperature/duration and drug concentration on the viability of the cancer cell lines versus normal human dermal fibroblasts. Two incubation scenarios were explored: (i) hyperthermic intraperitoneal chemotherapy (HIPEC) with 1 h of incubation at 42 °C, and (ii) pressurized intraperitoneal aerosol chemotherapy (PIPAC) with several successive incubations at 37 °C. Under HIPEC conditions, oxaliplatin induced a potent temperature-dependent growth inhibition of colon cancer cells not seen with the duplex drug. Under PIPAC conditions, the duplex drug achieved the same growth inhibition at a fraction of the dose level required with oxaliplatin. Gastric and ovarian cancer cells were more sensitive to cisplatin plus doxorubicin than to the duplex drug under PIPAC conditions. The duplex drug suggests itself, notably in cases of platinum resistance, as an alternative or addition to intraperitoneal chemotherapies when platinum-based PIPAC technology is used. Using it with HIPEC technology is not recommended. Higher doses of the duplex drug will enhance growth inhibition, albeit at the cost of a severely reduced difference in chemosensitivity between tumor and normal cells. Our findings provide orientation for PIPAC-based personalized intraperitoneal chemotherapy.

PIK3CA mutations confer resistance to first-line chemotherapy in colorectal cancer

Chemotherapy represents an important treatment option for colorectal cancer (CRC), but only half of the patients benefit from these regimens. We explored the potential predicting value and mechanism of PIK3CA mutation in CRC chemotherapy. CRC specimens from 440 patients were retrospectively collected and examined with a fluorescence PCR-based method. The correlation of first-line chemotherapy response and PIK3CA mutation was evaluated according to follow-up and medical records. The underlying mechanism of PIK3CA mutation in chemotherapy resistance was assessed with CRC tumors and primary cells. The mutation frequency of the PIK3CA gene in CRC patients was 9.55%, which was correlated with late TNM staging and lower histological grade. The CRC patients with PIK3A mutation showed worse response to first-line chemotherapy than those without PIK3CA mutation. PIK3A mutation tumor cells showed poor sensitivity to first-line chemotherapy in vitro and in vivo. PIK3CA mutation induced PI3K/Akt signaling activation to increase LGR5⁺ CRC stem cells survival and proliferation, from which lead to chemotherapy resistance. Furthermore, PIK3CA^mutation/LGR5⁺ expression was an independent detrimental factor for CRC patients. Our findings indicated that PIK3CA mutation induced PI3K/Akt activation contributed to CRC stem cells survival and proliferation, from which cells further resistance to chemotherapy. PIK3CA ^mutation/LGR5⁺ expression was a potential biomarker for monitoring chemotherapy resistance in CRC.

5-FU therapeutic drug monitoring as a valuable option to reduce toxicity in patients with gastrointestinal cancer

Aims

5-FU is used as the main backbone of chemotherapy regimens for patients with colorectal and other gastrointestinal cancers. Despite development of new strategies that allowed enhancing clinical effectiveness and tolerability of 5-FU, 10-30% of patients treated with 5-FU-based regimens experience severe treatment-related toxicity. In our study, we evaluated the 5-FU exposure-toxicity relationship and investigated the efficacy of PK-guided dosing in increasing tolerability of 5-FU-based chemotherapy.

Results

50.7% of patients required dose adjustments after cycle 1. Percentage of patients within 5-FU AUC range was 49.3%, 66.9%, 61.0% at cycle 1, 2 and 3 respectively (p = 0.002 cycle 1 vs cycle 2). At all 3 cycles, lower incidences of grade I/II toxicities were observed for patients below or within range compared with those above range (19.4% vs 41.3%, p < 0.001 respectively).

Conclusions

Our analysis confirms that the use of BSA-guided dosing results in highly variable 5-FU exposure and strongly suggests that PK-guided dosing can improve tolerability of 5-FU based chemotherapy in patients with gastrointestinal cancers, thus supporting 5-FU therapeutic drug monitoring.

Methods

155 patients with gastrointestinal cancers, who were to receive 5-FU-based regimens were included in our study. At cycle 1, the 5-FU dose was calculated using patient's Body Surface Area (BSA) method. A blood sample was drawn on Day 2 to measure 5-FU concentration. At cycle 2, the 5-FU dose was adjusted using a PK-guided dosing strategy targeting a plasma AUC range of 18-28 mg·h/L, based on cycle 1 concentration. Assessments of toxicity was performed at the beginning of every cycle.