Advanced Colorectal Cancer Patients Research Articles

An infodemiology study on exploring the quality and reliability of colorectal cancer immunotherapy information.

Immunotherapy is a new treatment modality which promises hope for advanced colorectal cancer patients. To our knowledge, no previous studies have evaluated the quality of patient information available on this topic online. This study will explore the quality and reliability of colorectal cancer immunotherapy information using the Journal of the American Medical Association (JAMA) and DISCERN tools. Design thinking methodology was integrated with systematic scoping reviews framework to inform our descriptive observational media analysis study. Google Chrome was used to run four searches using prespecified search terms selected according to the top patient concerns about immunotherapy. The first 20 relevant results were identified (n = 80) and then duplicates were removed. Descriptive narrative univariate and bivariate analysis was done for the relevant variables. The total of included websites was 17. Most websites score <3 points on JAMA and fair/poor on DISCERN. Most of the websites that score ≥3 points on JAMA and excellent/good on DISCERN have a charity affiliation. A total of 58.8% of the websites present the date, 41.2% demonstrate authorship, and sources are mentioned in 29.4% of the websites. Lack of content was noticed in providing the prognosis of patients if no treatment is given, clear aim and the effect of treatments on patient's quality of life. Assessing the reliability of information about cancer treatments online remains a challenge. Further research is required to understand the patient perceptions and use of online information and whether it has an impact on their behavioural health outcomes.

Deep learning-based assessment of body composition and liver tumour burden for survival modelling in advanced colorectal cancer.

Personalized therapy planning remains a significant challenge in advanced colorectal cancer care, despite extensive research on prognostic and predictive markers. A strong correlation of sarcopenia or overall body composition and survival has been described. Here, we explore whether automated assessment of body composition and liver metastases from standard of care CT images can add to clinical parameters in personalized survival risk prognostication. We retrospectively analysed clinical imaging data from 85 patients (50.6% female, mean age 58.9 SD 12.2years) with colorectal cancer and synchronous liver metastases. Pretrained deep learning models were used to assess body composition and liver metastasis geometry from abdominal CT images before the initiation of systemic treatment. Abdominal muscle-to-bone ratio (MBR) was calculated by dividing abdominal muscle volume by abdominal bone volume. MBR was compared with body mass index (BMI), abdominal muscle volume, and abdominal muscle volume divided by height squared. Differences in overall survival based on body composition and liver metastasis parameters were compared using Kaplan-Meier survival curves. Results were correlated with clinical and biomarker data to develop a machine learning model for survival risk prognostication. The MBR, unlike abdominal muscle volume or BMI, was significantly associated with overall survival (HR 0.39, 95% CI: 0.19-0.80, P=0.009). The MBR (P=0.022), liver metastasis surface area (P=0.01) and primary tumour sidedness (P=0.007) were independently associated with overall survival in multivariate analysis. Body composition parameters did not correlate with KRAS mutational status or primary tumour sidedness. A prediction model based on MBR, liver metastasis surface area and primary tumour sidedness achieved a concordance index of 0.69. Automated segmentation enables to extract prognostic parameters from routine imaging data for personalized survival modelling in advanced colorectal cancer patients.

Pharmacological Mechanism of Pingxiao Formula against Colorectal Cancer.

Colorectal cancer (CRC) is the most common cancer worldwide and develops due to a broad range of causative factors. Pingxiao (PX) formula and Xihuang (XH) formula are two commonly used drugs to treat CRC, especially as an alternative therapy for those patients who could not suffer surgery, chemotherapy, or immunotherapy, namely, elder or advanced CRC patients. However, the pertinent pharmacological mechanisms are still elusive. The investigation was designed to explain the pharmacological mechanisms of the PX formula. A murine model of CRC was established by injecting CT26.WT cells into the caecum of 4-week-old male Balb/c mice, following PX or XH treatment for 30 days. Network pharmacology analysis combined with weighted gene coexpression network analysis (WGCNA) predicted the pharmacological mechanisms and therapeutic value. High-throughput 16S rRNA sequencing determined the alterations in the gut microbiota communities. Western blotting, immunofluorescence, and flow cytometry examined the influence of PX on the tumor microenvironment (TME). Injection of CT26.WT-induced CRC in Balb/c mice was markedly attenuated by PX treatment. Compared with XH administration, PX exhibited a stronger antitumor effect, such as smaller tumor volume, lower interleukin 17 (IL-17), IL-6 and tumor necrosis factor-alpha (TNFα) serum levels, and higher interferon-gamma (IFN-γ) concentration. Network pharmacology analysis demonstrated that both PX and XH targets were enriched in cancers and inflammatory responses. RNA sequencing confirmed that PX treatment induced cancer cell apoptosis and inhibited inflammatory reactions within the tumor. Moreover, the PX formula considerably restored homeostasis of the gut microbiota, which was not observed in the XH group. PX targets, those associated with the survival probability of CRC patients, correlated with macrophage (Mφ) infiltration, which presented an independent risk factor for the CRC outcome. PX treatment promoted the transition of alternatively activated Mφs (M2 Mφs) to classically activated Mφs (M1 Mφs). Moreover, the peritoneal Mφs from the PX group inhibited the migration of CW26.WT cells, as evidenced by the wound healing experiment and transwell assay, which was consistent with the decreased expression of the vascular endothelial growth factor (VEGF). Furthermore, the coculturing system confirmed that PX-treated Mφs suppressed colorectal tumor-derived organoid proliferation. PX formula exhibits a potential antitumor effect against CRC by suppressing the colonization of pathological microorganisms, reshaping Mφ effector functions and hence inhibiting cancer cell proliferation.

HOXA13 serves as a biomarker to predict neoadjuvant therapy efficacy in advanced colorectal cancer patients.

Neoadjuvant therapy (NAT) for advanced colorectal cancer (ACRC) is a kind of well-evidenced therapy, yet a portion of ACRC patients have poor therapeutic response. To date, no suitable biomarker used for assessing NAT efficacy has been reported. Here, we collect 72 colonoscopy biopsy tissue specimens from ACRC patients before undergoing NAT and investigate the relationship between HOXA13 expression and NAT efficacy. The results show that HOXA13 expression in pretreated tumor specimens is negatively associated with tumor regression ( P<0.001) and progression-free survival ( P<0.05) in ACRC patients who underwent NAT. Silencing of HOXA13 or its regulator HOTTIP significantly enhances the chemosensitivity of colorectal cancer (CRC) cells, leading to an increase in cell apoptosis and the DNA damage response (DDR) to chemotherapeutic drug treatment. In contrast, HOXA13 overexpression causes a significant increase in chemoresistance in CRC cells. In summary, we find that the HOTTIP/HOXA13 axis is involved in regulating chemotherapeutic sensitivity in CRC cells by modulating the DDR and that HOXA13 serves as a promising marker for NAT efficacy prediction in ACRC patients.

The prognostic role of fasting plasma glucose levels on survival in advanced colorectal cancer patients with type II diabetes mellitus: a retrospective cohort study

Previous studies have shown that type II diabetes mellitus (T2DM) has a significant effect on the occurrence and development of colorectal cancer (CRC). The associations between fasting plasma glucose (FPG) and overall survival (OS) of CRC patients with T2DM are still controversial. The present study sought to examine the association between FPG control and OS in advanced CRC patients with T2DM. The data of advanced CRC patients with T2DM who were admitted to Harbin Medical University Cancer Hospital from May 2010 to May 2019 were retrospectively collected and examined. Record patient clinical data including age, sex, blood pressure, body mass index (BMI), primary tumor site, T stage, N stage, histological grade, number of metastatic sites, primary tumor surgery, etc. The baseline FPG which was measured before the first-line treatment and the FPG measured before each admission treatment during advanced chemotherapy were collected. OS was determined as the end point of the study. All the patients were followed-up for at least 3 years. The Kaplan-Meier log-rank method and the Cox proportional hazards regression analyses were used for the analysis of OS and hazard factors. A total of 210 patients met the inclusion criteria for the study, who had a median age of 66.5 years; 94 patients had baseline FPG levels ≤7 mmol/L, and 116 patients had baseline FPG levels >7 mmol/L. Compared to the baseline FPG >7 mmol/L group, the OS of patients in the baseline FPG ≤7 mmol/L group was not significantly prolonged (P=0.88). There were 52 patients in the FPG-A group and 61 in the FPG-B group. Similarly, there was no significant difference in OS between the FPG-A and FPG-B groups (P=0.96). The N0 stage subgroup analysis showed that glycemic control ≤7 mmol/L resulted in longer OS. The results of the present study showed that FPG levels may not affect the survival of advanced CRC patients with T2DM. However, this needs multicenter prospective studies to confirm.

Different Characteristics in Gut Microbiome between Advanced Adenoma Patients and Colorectal Cancer Patients by Metagenomic Analysis.

The occurrence and development of colorectal cancer (CRC) and advanced adenoma (AA) are closely related to the gut microbiome, and AA has a high cancerization progression rate to CRC. Current studies have revealed that bacteriological analysis cannot identify CRC from AA. The objective was to explore microbial targets that could identify CRC and AA from a microecological perspective and to figure out the best way to identify CRC based on fecal microbes. The metagenomic sequencing data were used to describe the gut microbiome profile and analyze the differences between microbial abundance and microbial single nucleotide polymorphism (SNP) characteristics in AA and CRC patients. It was found that there were no significant differences in the diversity between the two groups. The abundance of bacteria (e.g., Firmicutes, Clostridia, and Blautia), fungi (Hypocreales), archaea (Methanosarcina, Methanoculleus, and Methanolacinia), and viruses (Alphacoronavirus, Sinsheimervirus, and Gammaretrovirus) differed between AA and CRC patients. Multiple machine-learning algorithms were used to establish prediction models, aiming to identify CRC and AA. The accuracy of the random forest (RF) model based on the gut microbiome was 86.54%. Nevertheless, the accuracy of SNP was 92.31% in identifying CRC from AA. In conclusion, using microbial SNP was the best method to identify CRC, it was superior to using the gut microbiome, and it could provide new targets for CRC screening. IMPORTANCE There are differences in characteristic microorganisms between AA and CRC. However, current studies have indicated that bacteriological analysis cannot identify CC from AA, and thus, we wondered if there were some other targets that could be used to identify CRC from AA in the gut microbiome. The differences of SNPs in the gut microbiota of intraindividuals were significantly smaller than those of interindividuals. In addition, compared with intestinal microbes, SNP was less affected by time with certain stability. It was discovered that microbial SNP was better than the gut microbiome for identifying CRC from AA. Therefore, screening characteristic microbial SNP could provide a new research direction for identifying CRC from AA.

Micronuclei in Circulating Tumor Associated Macrophages Predicts Progression in Advanced Colorectal Cancer.

Micronuclei (MN) are fragments of damaged nucleic acids which budded from a cell's nuclei as a repair mechanism for chromosomal instabilities, which within circulating white blood cells (cWBCs) signifies increased cancer risk, and in tumor cells indicates aggressive subtypes. MN form overtime and with therapy induction, which requires sequential monitoring of rarer cell subpopulations. We evaluated the peripheral blood (7.5 mL) for MN in Circulating Stromal Cells (CStCs) in a prospective pilot study of advanced colorectal cancer patients (n = 25), identifying MN by DAPI+ structures (&lt;3 µm) within the cellular cytoplasm. MN+ was compared to genotoxic induction, progression free survival (PFS) or overall survival (OS) hazard ratios (HR) over three years. MN were identified in 44% (n = 11/25) of CStCs, but were not associated with genotoxic therapies (p = 0.110) nor stage (p = 0.137). However, presence of MN in CStCs was independently prognostic for PFS (HR = 17.2, 95% CI 3.6-80.9, p = 0.001) and OS (HR = 70.3, 95% CI 6.6-752.8, p = 0.002), indicating a non-interventional mechanism in their formation. Additionally, MN formation did not appear associated with chemotherapy induction, but was correlated with tumor response. MN formation in colorectal cancer is an underlying biological mechanism that appears independent of chemotherapeutic genotoxins, changes during treatment, and predicts for poor clinical outcomes.

Personalized targeted therapy prescription in colorectal cancer using algorithmic analysis of RNA sequencing data

Background:Overall survival of advanced colorectal cancer (CRC) patients remains poor, and gene expression analysis could potentially complement detection of clinically relevant mutations to personalize CRC treatments.Methods:We performed RNA sequencing of formalin-fixed, paraffin-embedded (FFPE) cancer tissue samples of 23 CRC patients and interpreted the data obtained using bioinformatic method Oncobox for expression-based rating of targeted therapeutics. Oncobox ranks cancer drugs according to the efficiency score calculated using target genes expression and molecular pathway activation data. The patients had primary and metastatic CRC with metastases in liver, peritoneum, brain, adrenal gland, lymph nodes and ovary. Two patients had mutations in NRAS, seven others had mutated KRAS gene. Patients were treated by aflibercept, bevacizumab, bortezomib, cabozantinib, cetuximab, crizotinib, denosumab, panitumumab and regorafenib as monotherapy or in combination with chemotherapy, and information on the success of totally 39 lines of therapy was collected.Results:Oncobox drug efficiency score was effective biomarker that could predict treatment outcomes in the experimental cohort (AUC 0.77 for all lines of therapy and 0.91 for the first line after tumor sampling). Separately for bevacizumab, it was effective in the experimental cohort (AUC 0.87) and in 3 independent literature CRC datasets, n = 107 (AUC 0.84–0.94). It also predicted progression-free survival in univariate (Hazard ratio 0.14) and multivariate (Hazard ratio 0.066) analyses. Difference in AUC scores evidences importance of using recent biosamples for the prediction quality.Conclusion:Our results suggest that RNA sequencing analysis of tumor FFPE materials may be helpful for personalizing prescriptions of targeted therapeutics in CRC.

The PaCES (Palliative Care Early and Systematic) Project: Impact of individual components of a multi-faceted intervention on early referral to specialist palliative care.

199 Background: Early referral to specialist palliative care can improve, or maintain, symptom and quality of life outcomes that matter most to patients facing life-limiting illnesses. We tested a multifaceted oncologist-facing intervention (Palliative Care Early and Systematic) in the real-world setting of a busy outpatient cancer clinic for its ability to increase the proportion of patients who receive early specialist palliative care (defined as ≥ 90 days before death). Herein, we describe how each component of the multi-faceted intervention, intended to bridge cancer, primary, and palliative care, impacted early use of specialist palliative care among advanced colorectal cancer patients. Methods: Two intervention components were implemented in Calgary, Alberta, Canada’s tertiary cancer centre from January 2019 to June 2020: 1) Adult colorectal cancer patients were referred to a community-based Clinical Nurse Specialist if they failed, or could not receive, first-line chemotherapy, or had high symptom burden (indicated by an Edmonton Symptom Assessment System Revised score ≥ 7); 2) Medical oncologists sent templated ‘Shared Care’ letters to patients’ primary care providers to improve communication, collaboration and role clarity. Results: N = 209 eligible patients died during the intervention period, of whom 57% experienced early referral to specialist palliative care. The median days from referral to death was 130 (IQR: 53-359). Of the 209, 28 (13%) saw the Clinical Nurse Specialist and received Shared Care letters, and all (100%) had early specialist palliative care referral (median 240 days, IQR: 161-359). 21/209 (10%) saw the Clinical Nurse Specialist but had no Shared Care letter. Of these 21, 76% had early specialist palliative care referral (median 197 days, IQR: 96-251). 43/209 (21%) had a Shared Care letter but no interaction with the Clinical Nurse Specialist. Of these 43, 53% had early specialist palliative care referral (median 102 days, IQR: 53-257). 117/209 (56%) did not interact with the Clinical Nurse Specialist or have a Shared Care letter. Of these 117, 45% had early specialist palliative care referral (median 86 days, IQR: 40-204). Conclusions: The Clinical Nurse Specialist was associated with the greatest increase in early specialist palliative care referral; however, the Clinical Nurse Specialist and Shared Care letters combined were associated with even greater (100%) early specialist palliative care use.

Identification of N6-methylandenosine related lncRNA signatures for predicting the prognosis and therapy response in colorectal cancer patients.

Despite recent advances in surgical and multimodal therapies, the overall survival (OS) of advanced colorectal cancer (CRC) patients remains low. Thus, discerning sensitive prognostic biomarkers to give the optimistic treatment for CRC patients is extremely critical. N6-methyladenosine (m6A) and long noncoding RNAs (lncRNAs) play an important role in CRC progression. Nonetheless, few studies have focused on the impact of m6A-related lncRNAs on the prognosis, tumor microenvironment (TME) and treatment of CRC. In this study, 1707 m6A-related lncRNAs were identified through Pearson correlation analysis and Weighted co-expression network analysis (WGCNA) using The Cancer Genome Atlas (TCGA) cohort. Then, 28 m6A-related prognostic lncRNAs were screened by univariate Cox regression analysis, followed by identifying two clusters by consensus clustering analysis. A prognostic model consisted of 8 lncRNA signatures was constructed by the least absolute shrinkage and selection operator (LASSO). Kaplan–Meier curve analysis and a nomogram were performed to investigate the prognostic ability of this model. The risk score of prognostic model act as an independent risk factor for OS rate. Functional enrichment analysis indicated that lncRNA signatures related tumor immunity. The low-risk group characterized by increased microsatellite instability-high (MSI-H), mutation burden, and immunity activation, indicated favorable odds of OS. Moreover, the lncRNA signatures were significantly associated with the cancer stem cell (CSC) index and drug sensitivity. In addition, 3 common immune genes shared by the lncRNA signatures were screened out. We found that these immune genes were widely distributed in 2 cell types of TME. Finally, a ceRNA network was constructed to identify ZEB1-AS1 regulatory axis in CRC. We found that ZEB1-AS1 was significantly overexpressed in tumor tissues, and was related to the metastasis of EMT and the chemoresistance of 5-Fu in CRC. Therefore, our study demonstrated the important role of m6A-related lncRNAs in TME remodeling. Moreover, these results illustrated the levels of ZEB1-AS1 might be valuable for predicting the progression and prognosis of CRC, and further provided a new target for the diagnosis and treatment of CRC patients.

Colorectal cancer organoid models uncover oxaliplatin-resistant mechanisms at single cell resolution.

Oxaliplatin-based chemotherapy is a standard treatment for advanced colorectal cancer (CRC) patients. However, chemoresistance-induced resistance is an essential cause for mortality. Therefore, it is necessary to study the mechanism of drug resistance in CRC. Here, we established two strains of patient-derived organoids (PDOs) selected from oxaliplatin-resistant and treatment-naïve CRC patients. To dissect the drug-resistant mechanisms, these CRC-PDOs were subjected to single-cell RNA sequencing (scRNA-Seq). We found that the drug sensitivity test outcome from these organoids subjected to oxaliplatin and 5-FU exposure was consistent with the clinic readout. CRC-PDOs well recapitulated the morphology and histology of their parental biopsies based on HE and IHC staining of pathological biomarkers. The scRNA-Seq data filtered drug-resistant cell populations and related signaling pathways (e.g. oxidative phosphorylation and ATP metabolic process). The data also revealed several putative drug resistant-driven genes (STMN1, VEGFA and NDRG1) and transcription factors (E2F1, BRCA1, MYBL2, CDX2 and CDX1). We generated an oxaliplatin-resistant CRC organoid model that was employed to provide potential therapeutic targets for treating CRC patients exhibiting oxaliplatin-resistance.

Evacetrapib Elicits Antitumor Effects on Colorectal Cancer by Inhibiting the Wnt/β-Catenin Signaling Pathway and Activating the JNK Signaling Pathway.

Despite advances in colorectal cancer (CRC) treatment, most advanced CRC patients who experience disease progression after chemotherapy, targeted therapy, and immunotherapy face a situation in which there is no available medicine. Thus, new therapeutic drugs for CRC are urgently needed. Studies have shown that cholesteryl ester transfer protein (CETP) has a vital role in tumor development and is a possible target for CRC therapy. We found that Evacetrapib, a CETP inhibitor, suppressed CRC cell growth by inhibiting the Wnt/β-catenin signaling pathway and activating the c-Jun NH2-terminal kinase (JNK) signaling pathway in CRC. Therefore, Evacetrapib displays an anti-cancer effect and is a possible option for treating CRC.

Early detection of colorectal cancer based on circular DNA and common clinical detection indicators.

BACKGROUNDColorectal cancer (CRC) is the third most common cancer worldwide, and it is the second leading cause of death from cancer in the world, accounting for approximately 9% of all cancer deaths. Early detection of CRC is urgently needed in clinical practice.AIMTo build a multi-parameter diagnostic model for early detection of CRC. METHODSTotal 59 colorectal polyps (CRP) groups, and 101 CRC patients (38 early-stage CRC and 63 advanced CRC) for model establishment. In addition, 30 CRP groups, and 62 CRC patients (30 early-stage CRC and 32 advanced CRC) were separately included to validate the model. 51 commonly used clinical detection indicators and the 4 extrachromosomal circular DNA markers NDUFB7, CAMK1D, PIK3CD and PSEN2 that we screened earlier. Four multi-parameter joint analysis methods: binary logistic regression analysis, discriminant analysis, classification tree and neural network to establish a multi-parameter joint diagnosis model. RESULTSNeural network included carcinoembryonic antigen (CEA), ischemia-modified albumin (IMA), sialic acid (SA), PIK3CD and lipoprotein a (LPa) was chosen as the optimal multi-parameter combined auxiliary diagnosis model to distinguish CRP and CRC group, when it differentiated 59 CRP and 101 CRC, its overall accuracy was 90.8%, its area under the curve (AUC) was 0.959 (0.934, 0.985), and the sensitivity and specificity were 91.5% and 82.2%, respectively. After validation, when distinguishing based on 30 CRP and 62 CRC patients, the AUC was 0.965 (0.930-1.000), and its sensitivity and specificity were 66.1% and 70.0%. When distinguishing based on 30 CRP and 32 early-stage CRC patients, the AUC was 0.960 (0.916-1.000), with a sensitivity and specificity of 87.5% and 90.0%, distinguishing based on 30 CRP and 30 advanced CRC patients, the AUC was 0.970 (0.936-1.000), with a sensitivity and specificity of 96.7% and 86.7%.CONCLUSIONWe built a multi-parameter neural network diagnostic model included CEA, IMA, SA, PIK3CD and LPa for early detection of CRC, compared to the conventional CEA, it showed significant improvement.

Liquid biopsy for KRAS, NRAS and BRAF mutation testing in advanced colorectal cancer patients: the Argentinean experience.

Objective: To analyze the frequency of KRAS, NRAS and BRAF hotspot mutations in circulating tumor DNA (ctDNA) from patients with metastatic colorectal cancer (mCRC). Methods: Observational, descriptive and retrospective study in mCRC patients with available ctDNA-based genotype of KRAS, NRAS and BRAF. Results: The frequencies of plasma mutations for KRAS, NRAS and BRAF were 34% (±7), 4% (±3) and 4% (±3), respectively. Median overall survival of plasma-tested RAS/BRAF-mutated patients was 26.6months (95% CI: 14.4-not estimable [NE]), while RAS/BRAF wild-type patients did not reach the median survival during follow-up. Median progression-free survival for RAS/BRAF wild-type and RAS/BRAF-mutated patients was 12 (95% CI: 7-NE) and 4months (95% CI: 4-NE), respectively. Conclusion: Our work supports the utility of KRAS, NRAS and BRAF analysis in liquid biopsy from mCRC patients.

Serial Circulating Tumor DNA in Monitoring the Effect of Neoadjuvant and Adjuvant Immunotherapy in Patients With Colon Cancer: Case Series and Review of the Literature.

Although programmed death 1 blockade has significantly improved the survival of advanced colorectal cancer patients with DNA mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H), clinical data in neoadjuvant and adjuvant setting are limited. The role of circulating tumor DNA (ctDNA) in precision oncology is promising, but its clinical significance in immunotherapy needs to be validated. We report a case series of 3 colon patients who received neoadjuvant and adjuvant immunotherapy and serial ctDNA analysis. This report summarizes clinical and molecular details for 3 patients with locally advanced or recurrent dMMR/MSI-H/polymerase epsilon ( POLE ) mutation-positive tumors treated with neoadjuvant/adjuvant immunotherapy. One stage IV recurrent colon cancer patient diagnosed with Lynch syndrome received adjuvant sintilimab monotherapy and had a progression-free survival (PFS) over 16 months, one stage Ⅲc colon cancer patient with MSI-H/high tumor mutation burden received neoadjuvant toripalimab monotherapy, was assessed as clinical complete response before surgery, continued with adjuvant sintilimab monotherapy and had a PFS over 17 months, one stage Ⅱ colon cancer patient with POLE P286R also received adjuvant sintilimab monotherapy and had a PFS over 17 months. All patients had detectable ctDNA after radical surgery and clearance of ctDNA during adjuvant immunotherapy. All 3 patients are free of tumor disease at the time of this report. Further studies are warranted to evaluate the long-term efficacy of neoadjuvant and adjuvant programmed death 1 blockade in locally advanced and metastasis in dMMR/MSI-H/ POLE mutated colorectal cancer and the role of ctDNA monitoring.

MO41-5 PD-L1 promoter methylation predicts survival in advanced colorectal cancer patients who received preoperative CCRT

Radiotherapy can boost the therapeutic response to immune checkpoint inhibitors (ICIs) by recruiting T lymphocytes and upregulating PD-L1 expression within the tumor microenvironment (TME). Our previous studies found that tumor PD-L1 expression cannot be induced in some locally advanced colorectal cancer (CRC) patients who receive preoperative concurrent chemoradiotherapy (CCRT) even in the presence of abundant T lymphocytes. We aimed to evaluate whether PD-L1 promoter methylation impacted the response to CCRT and acted as an independent biomarker for locally advanced CRC patients.

Dual inhibition of TGFβ signaling and CSF1/CSF1R reprograms tumor-infiltrating macrophages and improves response to chemotherapy via suppressing PD-L1

TGFβ contributes to chemoresistance in advanced colorectal cancer (CRC) via diverse immune-microenvironment mechanisms. Here, we found that cancer cell autonomous TGFβ directly triggered tumor programmed cell death 1 ligand 1 (PD-L1) upregulation, resulting in resistance to chemotherapy. Inhibition of tumor PD-L1 expression sensitized cancer cells to chemotherapy, reduced lung metastasis and increased the influx of CD8+ T cells. However, chemorefractory cancer cell-derived CSF1 recruited TAMs for TGFβ-mediated PD-L1 upregulation via a vicious cycle. High infiltration of macrophages was clinically correlated with the status of tumor PD-L1 after chemotherapy treatment in CRC patients. We found that depletion of immunosuppressive CSF1R+ TAM infiltration and blockade of the TGFβ receptor resulted in an increased influx of cytotoxic CD8+ T and effector memory CD8+ cells, a reduction in regulatory T cells, and a synergistic inhibition of tumor growth when combined with chemotherapy. These findings show that CSF1R+ TAMs and TGFβ are the dominant components that regulate PD-L1 expression within the immunosuppressive tumor microenvironment, providing a therapeutic strategy for advanced CRC patients.

Abstract 1250: Impact of homologous recombination repair or mismatch repair gene alteration on first-line FOLFOX chemotherapy in advanced colorectal cancer patients: K-MASTER project

Abstract Purpose: Homologous recombination repair (HRR) and mismatch repair (MMR) alteration is known to have a good response to platinum-based chemotherapy in both breast and ovarian cancer. However, HRR/MMR alteration and response for 1L FOLFOX chemotherapy in advanced colorectal cancer (CRC) is not fully understood. Methods: From 2017 to 2021, a number of 1,225 advanced CRC patients with available HRR/MRR alteration data were registered in K-MASTER project. After excluding missing data, adjuvant chemotherapy alone, other chemotherapeutic regimen, 390 patients who received 1L FOLFOX chemotherapy were finally analyzed. Targeted sequencing was conducted using Cancer Scan panel, FIRST panel, and K-MASTER Cancer (v1.0 or v1.1) panel for tumor tissue. If tumor tissue was not available, liquid biopsy was performed. HRR gene defined as follow; ATM, ATR, BARD1, BRCA1, BRCA2, BRIP1, CHEK2, FANCA, FANCD2, FANCG, PALB2, RAD50, RAD51. MMR gene defined as below; MLH1, MSH2, PMS2, MSH6, POLE, ARID1A. Results: Among 340 patients, 79 patients harbored HRR/MMR alteration. The median progression free survival (PFS) was 5.6 months vs 5.7 months in HRR/MMR alteration and wild-type group, respectively (hazard ratio (HR)=1.19, p-value=0.21). The median overall survival (OS) was comparable between two group (40.6 months vs 34.5 months, respectively; HR=0.71, p-value=0.17). Multivariate cox-proportional hazard model also showed HRR/MRR alteration status was not an independent factor for both PFS and OS (Both p-value&amp;gt;0.05). Conclusions: Patients harbored HRR/MRR alteration may not be sensitive for 1L oxaliplatin-based chemotherapy than wild-type. The effective treatment targeting high genomic instability populations warrants further investigation in CRC. Table 1. Baseline clinical characteristics and survival outcomes HRR/MMR alteration (n = 79) HRR/MMR wild-type (n = 261) P-value Age, year 58.5 ± 12.4 59.1 ± 12.8 0.710 Primary tumor resection, n (%) 70 (88.6%) 241 (92.3%) 0.298 Prior neoadjuvant or adjuvant chemotherapy, n (%) 10 (12.7%) 27 (10.3%) 0.212 Clinical stage IV, n (%) 71 (91.0%) 240 (92.7%) 0.855 Combined target agents, n (%) 54 (68.4%) 183 (70.1%) 0.811 HRR/MMR variants, n (%) N/A HRR mutation alone 38 (48.1%) - MMR mutation alone 30 (38.0%) - HRR+MMR mutation 11 (13.9%) - Median PFS (95% CI), months 5.6 (4.9-6.3) 5.7 (5.5-5.9) 0.215 Median OS (95% CI), months 40.6 (39.5-41.8) 34.5 (29.3-39.8) 0.175 Citation Format: Myung Han Hyun, Jwa Hoon Kim, Ah Reum Lim, Jae Sook Sung, Hee-Joon Chung, Yeul Hong Kim, Soohyeon Lee. Impact of homologous recombination repair or mismatch repair gene alteration on first-line FOLFOX chemotherapy in advanced colorectal cancer patients: K-MASTER project [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1250.

A Comprehensive Metabolomics Analysis of Fecal Samples from Advanced Adenoma and Colorectal Cancer Patients.

Accurate diagnosis of colorectal cancer (CRC) still relies on invasive colonoscopy. Noninvasive methods are less sensitive in detecting the disease, particularly in the early stage. In the current work, a metabolomics analysis of fecal samples was carried out by ultra-high-performance liquid chromatography–tandem mass spectroscopy (UPLC-MS/MS). A total of 1380 metabolites were analyzed in a cohort of 120 fecal samples from patients with normal colonoscopy, advanced adenoma (AA) and CRC. Multivariate analysis revealed that metabolic profiles of CRC and AA patients were similar and could be clearly separated from control individuals. Among the 25 significant metabolites, sphingomyelins (SM), lactosylceramides (LacCer), secondary bile acids, polypeptides, formiminoglutamate, heme and cytidine-containing pyrimidines were found to be dysregulated in CRC patients. Supervised random forest (RF) and logistic regression algorithms were employed to build a CRC accurate predicted model consisting of the combination of hemoglobin (Hgb) and bilirubin E,E, lactosyl-N-palmitoyl-sphingosine, glycocholenate sulfate and STLVT with an accuracy, sensitivity and specificity of 91.67% (95% Confidence Interval (CI) 0.7753–0.9825), 0.7 and 1, respectively.

Abstract 3489: Luminex-based analysis of serum CXC chemokines showing their usefulness as prognostic and/or predictive biomarkers in metastatic colorectal cancer patients

Abstract Introduction: CXC chemokines are a family of small, secreted, chemotactic molecules acting through the binding to their corresponding CXC receptors (CXCRs) and stimulating the migration of cells, most notably those of the immune system. They have been associated with both pro-tumor and anti-tumor activity. Previously, we reported increased expression and secretion levels of CXCL1, 2 and 8 in oxaliplatin (OXA)-resistant colorectal cancer (CRC) cell lines. The aim of this study is to evaluate the usefulness of measuring the serum levels of a CXC chemokine panel in CRC patients as prognostic and/or predictive biomarkers of first-line treatment. Material and Methods: In this multicenter study sera from advanced CRC patients to be treated with OXA-based schedules were collected at three different time points between November 2016 and June 2021: before treatment (PRET), at first response evaluation (EVAR) and at the time of progression/end of study (PROG). Levels of CXCL1, 2, 5, 6, 8, 9, 10, 11, 12, 13, 16 chemokines were analyzed using a custom Bio-plex Pro Human assay (Bio-Rad, USA) in a Luminex® 200 equipment. Comparisons of chemokines’ levels between Responders (R) and Non-Responders (NR) at different time-points were carried out using the Mann Whitney U and Wilcoxon tests. Log Rank and Cox regression were used to study differences in progression-free (PFS) and overall survival (OS); Chi-square or Fisher’s tests were used to study associations between categorical variables. All differences were considered statistically significant when p values ≤ 0.05. Results: A total of 107 patients were enrolled in this study: 72% male; median age 66 years old; metastasis: 78% liver, 41% lung; mutations: 44% KRAS, 4% BRAF; treatments: FOLFOX/XELOX = 30%/4% plus Bevacizumab/anti-EGFR = 36%/24%; 64% responders (complete response + partial response); 13% stable disease; 11% progressors. All chemokines could be detected in the samples. Levels below median (LBM) of CXCL1, 8, 11 and 13 correlated with better OS (HR=0.55 p=0.02; HR=0.47 p=0.005; HR=0.6 p=0.05; HR=0.54 p=0.02, respectively). LBM of CXCL16 correlated with better OS and PFS (HR=0.6 p=0.04; HR=0.6 p=0.005) and of CXCL5 with better PFS (HR 0.6 p 0.011); mean CXCL9 levels were lower in responders’ PRET samples (p=0.03) and LBM correlated with better OS (HR=0.5 p=0.019). In responders, all chemokines except CXCL10, 13 and 16 presented decreased levels at EVAR vs. PRET. Moreover, CXCL1, 2, 5, 8, 11 and 16 levels increased at PROG vs. EVAR. In non-responders, non-conclusive results were found. Conclusion: our results show that serum levels of specific CXC chemokines may be used as prognostic/predictive markers in metastatic CRC. Further analysis will be performed, and an update of this study will be presented in the AACR meeting. Citation Format: Sara Cabrero-de las Heras, Ferran Losa, Xavier Hernández-Yagüe, Gemma Soler, Cristina Bugés, Iosune Baraibar, Andrea Plaja, Eduard Teixidor, Eva Martínez-Balibrea. Luminex-based analysis of serum CXC chemokines showing their usefulness as prognostic and/or predictive biomarkers in metastatic colorectal cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3489.