Regimen For Colorectal Cancer Research Articles

The efficacy of targeted therapy and/or immunotherapy with or without chemotherapy in patients with colorectal cancer: A network meta-analysis.

The use of targeted drugs and immunotherapy has significantly impacted the treatment of Colorectal Cancer. However, horizontal comparison among various regimens is extremely rare. Therefore, we evaluated the survival efficacy of multiple treatment regimens of targeted therapy and/or immunotherapy with or without chemotherapy in patients with Colorectal Cancer. A systematic search was conducted in PubMed, EMBASE, and Cochrane databases, covering the period from the establishment of the databases to October 29, 2024. To obtain articles that met the inclusion and exclusion criteria and contained the required data for conducting a network meta-analysis (NMA). The NMA evaluated overall survival (OS) and progression-free survival (PFS). A total of 90 studies were identified, comprising a sample size of 33,167 subjects. In terms of PFS, compared with simple chemotherapy strategies, most of the other single or combined strategies are significantly effective, among which targeted therapy strategies have more advantages. Encorafenib+Binimetinib+Cetuximab (ENC-BIN-CET) shows significant benefits in all comparisons except when compared with Chemotherapy+Cetuximab+Dalotuzumab (Chemo-CET-DAL), Encorafenib+Cetuximab (ENC-CET), and Panitumumab+Sotorasib (PAN-SOT). The ENC-CET and PAN-SOT targeted strategies also show significant benefits. Pembrolizumab (PEM) monotherapy has advantages over all others except when it is not superior to some targeted strategies. Chemotherapy+Bevacizumab+Atezolizumab is only inferior to some strategies. In terms of OS, the combinations of Chemotherapy+Bevacizumab, ENC-CET, Chemotherapy+Panitumumab, and ENC-BIN-CET are superior to simple chemotherapy regimens. ENC-BIN-CET shows OS benefits in all comparisons except some. ENC-CET significantly improves OS in most cases, and PEM also significantly improves OS in some regimens. In the probability ranking of OS and PFS, ENC-BIN-CET has the best effect, followed by ENC-CET. In conclusion, pembrolizumab is still effective in prolonging survival. Dual- and triple-drug targeted strategies are the best in terms of OS and PFS, and the combination of targeted immunotherapy and chemotherapy also works. However, not all combinations are beneficial. As targeted drugs play an active role, specific drugs for colorectal cancer regimens should be carefully selected.

Cost-effectiveness analysis of trifluridine/tipiracil combined with bevacizumab vs. monotherapy for third-line treatment of colorectal cancer.

The combination of trifluridine/tipiracil (FTD/TPI) and bevacizumab has demonstrated promising efficacy and safety in the treatment of colorectal cancer (CRC). This study aims to evaluate the cost-effectiveness of trifluridine/tipiracil combined with bevacizumab vs. trifluridine/tipiracil monotherapy as a third-line treatment regimen for colorectal cancer within the Chinese healthcare system, providing an economic basis for clinical application. Based on data from the SUNLIGHT Phase III clinical trial, a dynamic Markov model was constructed with a cycle length of 4 weeks and a simulation duration of 10 years. Direct medical costs and quality-adjusted life years (QALYs) were calculated. The incremental cost-effectiveness ratio (ICER) was compared with the willingness-to-pay threshold (WTP = ¥268,200.00/QALY) to assess the economic viability of the treatment regimen. One-way sensitivity analysis and probabilistic sensitivity analysis were conducted to verify the robustness of the model results. The cost of trifluridine/tipiracil combined with bevacizumab treatment (¥838,492.74) was higher than that of trifluridine/tipiracil monotherapy (¥357,396.97), with greater health benefits (2.45 QALYs vs. 1.54 QALYs). The ICER was ¥527,577.36/QALY, exceeding the willingness-to-pay threshold. One-way sensitivity analysis indicated that drug costs and utility values during the progression-free period significantly impacted model outputs. Probabilistic sensitivity analysis further confirmed the robustness of the results, showing that at a willingness-to-pay threshold of ¥494,000.00, the probability of the combined treatment being cost-effective was 50%. Trifluridine/tipiracil combined with bevacizumab, as a third-line treatment for colorectal cancer, does not have a cost-effectiveness advantage compared to trifluridine/tipiracil monotherapy in economic evaluations.

Antagonistic roles of cGAS/STING signaling in colorectal cancer chemotherapy.

FOLFOX, composed of 5-FU, oxaliplatin and leucovorin, is a first line chemotherapy regimen for colorectal cancer (CRC) treatment. In this study, we show that 5-FU and oxaliplatin induce DNA damage and activate cGAS/STING signaling leading to enhanced expression of interferon (IFN) β, IFN-stimulated genes and inflammatory cytokines in mouse and human colon cancer cells as well as increased intratumoral CD8+ T cells in mice. Crucially, 5-FU and oxaliplatin increase PD-L1 expression at the mRNA and protein levels, which has been shown to inhibit CD8+ T cell function. Depletion of cGAS, STING, IRF3, or IFNα/β receptor 1 (IFNAR1) abolishes this increase, indicating that 5-FU/oxaliplatin mediated upregulation of PD-L1 expression is dependent on tumor cell intrinsic cGAS/STING signaling. These results imply opposing roles for FOLFOX during cancer treatment. On one hand, 5-FU and oxaliplatin activate the innate immune response to facilitate anti-tumor immunity, and conversely upregulate PD-L1 expression to evade immune surveillance. Analysis of TCGA colon cancer dataset shows a positive correlation between expression of PD-L1 and components of the cGAS/STING pathway, supporting a role for cGAS/STING signaling in upregulating PD-L1 expression in colon cancer patients. Tumor studies in syngeneic immune competent mice demonstrate that the combination of 5-FU/oxaliplatin and anti-PD-1 significantly reduced tumor growth of colon cancer cells compared to 5-FU/oxaliplatin treatment alone. Taken together, our studies have identified a unique pathway leading to chemoresistance and provide a rationale to combine FOLFOX with anti-PD-1/PD-L1 as an effective CRC treatment.

Translational Pharmacokinetic-Toxicodynamic Model of Myelosuppression for Dose Optimization in Combination Chemotherapy of Capecitabine and Oxaliplatin from Rats to Humans.

XELOX therapy, which comprises capecitabine and oxaliplatin, is the standard first-line chemotherapeutic regimen for colorectal cancer. However, its myelosuppressive effects pose challenges for its clinical management. Mathematical modeling combining pharmacokinetics (PK) and toxicodynamics (TD) is a promising approach for optimizing dosing strategies and reducing toxicity. This study aimed to develop a translational PK-TD model using rat data to inform dosing strategies and TD implications in humans. The rats were administered capecitabine, oxaliplatin, or XELOX combination regimen, and PK and TD data were collected. PK parameters were analyzed using sequential compartment analysis, whereas TD responses were assessed using Friberg's semiphysiological model. A toxicity intensity-based nomogram recommends optimal dosing strategies. Translational modeling techniques using the hybrid PK-TD model were employed to predict clinical responses. The PK-TD model successfully predicted the time-course profiles of hematological responses in rats following monotherapy and XELOX combination treatment. Interactive effects on lymphocytopenia were identified with the coadministration of capecitabine and oxaliplatin. A model-based recommended combination of the dose reduction rate for escaping severe lymphocytopenia was proposed as 40% and 60% doses of capecitabine and oxaliplatin, respectively. The current translational model techniques successfully simulated the time-course profiles of blood cell counts with confidence intervals in patients using rat data. Our study provides valuable insights into dose optimization strategies for each individual drug within the XELOX regimen and underscores the potential of translational modeling to improve patient outcomes. In addition to dose determination, these data will lay the groundwork for advancing drug development processes in oncology. SIGNIFICANCE STATEMENT: This study introduced a novel translational modeling approach rooted in a rat PK-TD model to optimize dosing strategies for the XELOX regimen for colorectal cancer treatment. Our findings highlight the interactive effects on lymphocytopenia and suggest a toxicity intensity-based nomogram for dose reduction, thus advancing precision medicine. This translational modeling paradigm enhances our understanding of drug interactions, offering a tool to tailor dosing, minimize hematological toxicity, and improve therapeutic outcomes in patients undergoing XELOX therapy.

Efficacy comparison of fruquintinib, regorafenib monotherapy or plus programmed death-1 inhibitors for microsatellite stable metastatic colorectal cancer.

Regorafenib (R) and fruquintinib (F) are the standard third-line regimens for colorectal cancer (CRC) according to the National Comprehensive Cancer Network guidelines, but both have limited efficacy. Several phase 2 trials have indicated that R or F combined with immune checkpoint inhibitors can reverse immunosuppression and achieve promising efficacy for microsatellite stable or proficient mismatch repair (MSS/pMMR) CRC. Due to the lack of studies comparing the efficacy between F, R, F plus programmed death-1 (PD-1) inhibitor, and R plus PD-1 inhibitors (RP), it is still unclear whether the combination therapy is more effective than monotherapy. To provide critical evidence for selecting the appropriate drugs for MSS/pMMR metastatic CRC (mCRC) patients in clinical practice. A total of 2639 CRC patients were enrolled from January 2018 to September 2022 in our hospital, and 313 MSS/pMMR mCRC patients were finally included. A total of 313 eligible patients were divided into F (n = 70), R (n = 67), F plus PD-1 inhibitor (FP) (n = 95) and RP (n = 81) groups. The key clinical characteristics were well balanced among the groups. The median progression-free survival (PFS) of the F, R, FP, and RP groups was 3.5 months, 3.6 months, 4.9 months, and 3.0 months, respectively. The median overall survival (OS) was 14.6 months, 15.7 months, 16.7 months, and 14.1 months. The FP regimen had an improved disease control rate (DCR) (P = 0.044) and 6-month PFS (P = 0.014) and exhibited a better trend in PFS (P = 0.057) compared with F, and it was also significantly better in PFS than RP (P = 0.030). RP did not confer a significant survival benefit; instead, the R group had a trend toward greater benefit with OS (P = 0.080) compared with RP. No significant differences were observed between the R and F groups in PFS or OS (P > 0.05). FP is superior to F in achieving 6-month PFS and DCR, while RP is not better than R. FP has an improved PFS and 6-month PFS compared with RP, but F and R had similar clinical efficacy. Therefore, FP may be a highly promising strategy in the treatment of MSS/pMMR mCRC.

APOA5 alleviates reactive oxygen species to promote oxaliplatin resistance in PIK3CA-mutated colorectal cancer.

Although platinum-based chemotherapy is the frontline regimen for colorectal cancer (CRC), drug resistance remains a major challenge affecting its therapeutic efficiency. However, there is limited research on the correlation between chemotherapy resistance and lipid metabolism, including PIK3CA mutant tumors. In this present study, we found that PIK3CA-E545K mutation attenuated cell apoptosis and increased the cell viability of CRC with L-OHP treatment in vitro and in vivo. Mechanistically, PIK3CA-E545K mutation promoted the nuclear accumulation of SREBP1, which promoted the transcription of Apolipoprotein A5 (APOA5). APOA5 activated the PPARγ signaling pathway to alleviate reactive oxygen species (ROS) production following L-OHP treatment, which contributed to cell survival of CRC cells. Moreover, APOA5 overexpression enhanced the stemness-related traits of CRC cells. Increased APOA5 expression was associated with PIK3CA mutation in tumor specimens and poor response to first-line chemotherapy, which was an independent detrimental factor for chemotherapy sensitivity in CRC patients. Taken together, this study indicated that PIK3CA-E545K mutation promoted L-OHP resistance by upregulating APOA5 transcription in CRC, which could be a potent target for improving L-OHP chemotherapeutic efficiency. Our study shed light to improve chemotherapy sensitivity through nutrient management in CRC.

Ketogenesis attenuated KLF5 disrupts iron homeostasis via LIF to confer oxaliplatin vulnerability in colorectal cancer

Oxaliplatin has been included as a basal drug in various chemotherapy regimens for colorectal cancer (CRC), a global health concern. However, acquired resistance to oxaliplatin affects the prognosis. This study aimed to determine whether the consumption of a KD increases the sensitivity of CRC cells to oxaliplatin via the inhibition of a classical stem cell marker, Krupple-like factor 5 (KLF5). KLF5 functions as a transcription factor for the leukemia inhibitory factor (LIF) and directly binds to its promoter region. LIF upregulation induces dephosphorylation of metal regulatory transcription factor 1 (MTF1), which is recruited to the promoter area of Ferroportin (FPN1), the only cellular iron exporter. FPN1 upregulation reduces the labile iron pool (LIP) and ferroptosis in CRC cells. KLF5 knockdown inhibits the LIF/MTF1/FPN1 axis and induces iron overload, thereby conferring sensitivity to oxaliplatin to CRC cells. KD mimicked KLF5 silencing and sensitized CRC cells to oxaliplatin via a similar mechanism. Thus, potential correlations were observed among ketogenesis, stemness, and iron homeostasis. This finding can be used to formulate a new strategy for overcoming oxaliplatin resistance in patients with CRC.

Combination chemotherapy against colorectal cancer cells: Co-delivery of capecitabine and pioglitazone hydrochloride by polycaprolactone-polyethylene glycol carriers

Colorectal cancer causes numerous deaths despite many treatment options. Capecitabine (CAP) is the standard chemotherapy regimen for colorectal cancer, and pioglitazone hydrochloride (PGZ) for diabetic disease treatment. However, free drugs do not induce effective apoptosis. This work aims to co-encapsulate CAP and PGZ and evaluate cytotoxic and apoptotic effects on HCT-119, HT-29 colorectal cancer cells, and human umbilical vein endothelial cells (HUVECs). CAP, PGZ, and combination treatment nano-formulations were prepared by triblock (TB) (PCL-PEG-PCL) biodegradable copolymers to enhance drugs' bioavailability as anti-cancer agents. The Ultrasonic homogenization method was used for preparing nanoparticles. The physicochemical characteristics of nanoparticles were studied using 1H NMR, FTIR, DLS, and FESEM techniques. The zeta potential, entrapment efficiency, drug release, and storage stability were studied. Also, cell viability and apoptosis were examined by using MTT, acridine orange (AO), and propidium iodide (PI), respectively. The smaller hydrodynamic size (236.1nm), polydispersity index (0.159), and zeta potential (-20.8mV) were observed in nanoparticles. Nanoparticles revealed a proper formulation and storage stability at 25°C than 4°C in 90days. The synergistic effect was observed in (CAP-PGZ)-loaded TB nanoparticles in HUVEC, HCT-116, and HT-29 cells. In (AO/PI) staining, the high percentage of apoptotic cells in the (CAP-PGZ)-loaded TB nanoparticles in HUVEC, HCT-116, and HT-29 were calculated as 78%, 71.66%, and 69.31%, respectively. The (CAP-PGZ)-loaded TB nanoparticles in this research offer an effective strategy for targeted combinational colorectal cancer therapy.

Regorafenib activates oxidative stress by inhibiting SELENOS and potentiates oxaliplatin-induced cell death in colon cancer cells

Colorectal cancer (CRC) is the third most common cancer, and is one of the leading causes of cancer-related death worldwide. At the time of diagnosis, about 20% of patients with CRC present metastatic disease. Regorafenib, an oral multi-kinase inhibitor, has been demonstrated the efficacy and tolerability in patients with metastatic CRC. Oxaliplatin is a frontline treatment regimen for CRC, and combination treatments with oxaliplatin and other chemotherapeutic agents exert superior therapeutic effects. However, side effects and drug resistance limited their further clinical application. Here, we found that combined treatment with regorafenib and oxaliplatin synergistically enhanced anti-tumor activities in CRC by activating reactive oxygen species (ROS) mediated endoplasmic reticulum (ER) stress, C-Jun-amino-terminal kinase (JNK) and p38 signaling pathways. Regorafenib promoted ROS production by suppressing the expression of selenoprotein S (SELENOS). Knocking down SELENOS sensitized ROS-mediated anti-tumor effects of regorafenib in CRC cells. Furthermore, mouse xenograft models demonstrated that synergistic anti-tumor effects of combined treatment with regorafenib and oxaliplatin. This study provided solid experimental evidences for the combined treatment with regorafenib and oxaliplatin in CRC.

Brevilin A exerts anti-colorectal cancer effects and potently inhibits STAT3 signaling invitro

Colorectal cancer (CRC) is the third most common cause of cancer-related morbidity worldwide, with an estimated of 1.85 million new cases and 850,000 deaths every year. Nevertheless, the current treatment regimens for CRC have many disadvantages, including toxicities and off-targeted side effects. STAT3 (signal transducer and activator of transcription 3) has been considered as a promising molecular target for CRC therapy. Brevilin A, a sesquiterpene lactone compound rich in Centipedae Herba has potent anticancer effects in nasopharyngeal, prostate and breast cancer cells by inhibiting the STAT3 signaling. However, the anti-CRC effect of brevilin A and the underlying mechanism of action have not been fully elucidated. In this study, we aimed to investigate the involvement of STAT3 signaling in the anti-CRC action of brevilin A. Here, HCT-116 and CT26cell models were used to investigate the anti-CRC effects of brevilin A in vitro. HCT-116cells overespressing with STAT3 were used to evaluate the involvement of STAT3 signaling in the anti-CRC effect of brevilin A. Screening of 49 phosphorylated tyrosine kinases in the HCT-116cells after brevilin A treatment was performed by using the human phospho-receptor tyrosine kinase (phospho-RTK) array. Results showed that brevilin A inhibited cell proliferation and cell viability, induced apoptosis, reduced cell migration and invasion, inhibited angiogenesis, lowered the protein expression levels of phospho-Src (Tyr416), phospho-JAK2 (Y1007/1008) and phospho-STAT3 (Tyr705), and inhibited STAT3 activation and nuclear localization. Brevilin A also significantly reduced the protein expression levels of STAT3 target genes, such as MMP-2, VEGF and Bcl-xL. More importantly, over-activation of STAT3 diminished brevilin A's effects on cell viability. All these results suggest that brevilin A exerts potent anti-CRC effects, at least in part, by inhibiting STAT3 signaling. Our findings provide a strong pharmacological basis for the future exploration and development of brevilin A as a novel STAT3-targeting phytotherapeutic agent for CRC treatment.

Cryptolepine Suppresses Colorectal Cancer Cell Proliferation, Stemness, and Metastatic Processes by Inhibiting WNT/β-Catenin Signaling.

Colorectal cancer (CRC) is the third most frequent cancer and the second leading cause of cancer-related deaths globally. Evidence shows that over 90% of CRC cases are initiated by a deregulated Wingless Integrated Type-1 (WNT)/β-catenin signaling pathway. The WNT/β-catenin pathway also promotes CRC cell proliferation, stemness, and metastasis. Therefore, modulators of the WNT/β-catenin pathway may serve as promising regimens for CRC. This study investigated the effect of cryptolepine-a plant-derived compound-on the WNT/β-catenin pathway in CRC. Two CRC cell lines, COLO205 and DLD1, were treated with cryptolepine or XAV 939 (a WNT inhibitor) in the presence or absence of WNT3a (a WNT activator). Using a tetrazolium-based assay, cryptolepine was found to reduce cell viability in a dose- and time-dependent manner and was a more potent inhibitor of viability than XAV 939. RT-qPCR analyses showed that cryptolepine reverses WNT3a-induced expression of β-catenin, c-MYC, and WISP1, suggesting that cryptolepine inhibits WNT3a-mediated activation of WNT/β-catenin signaling. Cryptolepine also repressed WNT3a-induced OCT4 and CD133 expression and suppressed colony formation of the cells, indicating that cryptolepine inhibits the stemness of CRC cells. Additionally, cryptolepine inhibited WNT3a-induced epithelial-to-mesenchymal transition by reducing the expression of SNAI1 and TWIST1 genes. In a wound healing assay, cryptolepine was found to suppress cell migration under unstimulated and WNT3a-stimulated conditions. Moreover, cryptolepine downregulated WNT3a-induced expression of MMP2 and MMP9 genes, which are involved in cancer cell invasion. Altogether, cryptolepine suppresses CRC cell proliferation, stemness, and metastatic properties by inhibiting WNT3a-mediated activation of the WNT/β-catenin signaling pathway. These findings provide a rationale for considering cryptolepine as a potential WNT inhibitor in CRC.

Advances in three-dimensional tumor models for colorectal cancer

Conventional tumor culture models include two-dimensional tumor cell cultures and xenograft models. The former has disadvantages including lack of tumor heterogeneity and poor clinical relevance, while the latter are limited by the slow growth, low engraftment successful rate, and high cost. In recent years, in vitro three-dimensional (3D) tumor models have emerged as the tool to better recapitulate the spatial structure and the in vivo environment of tumors. In addition, they preserve the pathological and genetic features of tumor cells and reflect the complex intracellular and extracellular interactions of tumors, which have become a powerful tool for investigating the tumor mechanism, drug screening, and personalized cancer treatment. 3D tumor model technologies such as spheroids, organoids, and microfluidic devices are maturing. Application of new technologies such as co-culture, 3D bioprinting, and air-liquid interface has further improved the clinical relevance of the models. Some models recapitulate the tumor microenvironment, and some can even reconstitute endogenous immune components and microvasculature. In recent years, some scholars have combined xenograft models with organoid technology to develop matched in vivo/in vitro model biobanks, giving full play to the advantages of the two technologies, and providing an ideal research platform for individualized precision therapy for specific molecular targets in certain subtypes of tumors. So far, the above technologies have been widely applied in the field of colorectal cancer research. Our research team is currently studying upon the application of patient-derived tumor cell-like clusters, a self-assembly 3D tumor model, in guiding the selection of postoperative chemotherapy regimens for colorectal cancer. A high modeling success rate and satisfactory results in the drug screening experiments have been achieved. There is no doubt that with the advancement of related technologies, 3D tumor models will play an increasingly important role in the research and clinical practice of colorectal cancer.

Efficacy of vemurafenib based regimens in colorectal cancer: A systematic review of clinical trials.

e15566 Background: Colorectal cancer (CRC) is the 3rd most common cancer worldwide, and BRAF gene mutation is present in almost 10% of these cancers. It results in constitutive activation of the mitogen-activated protein kinase pathway (MAPKP). Abnormal activation of MAPKP leads to uncontrolled mitotic activity and inhibition of apoptosis. In this systematic review, we will assess the efficacy of vemurafenib (BRAF inhibitor) based regimens in CRC. Methods: We followed PRISMA guidelines to conduct this systematic review. A literature search was performed on PubMed, Clinicaltirals.gov, and Embase with mesh terms, ‘’Colorectal Neoplasms’’ and “Proto-Oncogene Proteins B-raf” from the inception of data till 01/05/2023. We screened 4572 articles and included 1 randomized clinical trial (RCT, N = 100), and 4 non-randomized trials (nRCTs, N = 85), measuring the efficacy of vemurafenib (V) based regimens in BRAF V600E-mutated CRC. Results: In 5 clinical trials (N = 185), 90 patients were treated with triple therapy, 45 with dual therapy, and 50 were in the control arm. In triple therapy, 69 patients were treated with V plus irinotecan (I) and cetuximab (C), overall response rate (ORR) was 17% and 35%, and progression-free survival (PFS) was 4.2 and 7.7 months in the randomized and the non-randomized study, respectively. PFS was improved significantly with a hazard ratio (HR) of 0.50 (95% CI, 0.32 to 0.76, P = .001) in favor of V+I+C compared to C+I. Among combinations of V+C, adding 5-fluorouracil/leucovorin/irinotecan (FOLFIRI) as third combination showed the highest ORR of 81% and overall survival (OS) and PFS of 15.4 and 9.7 months, respectively. In two drug regimens, V was combined with Cobimetinib (Co) and Panitumumab (P) in two non-randomized studies, and partial response (PR) was 26% and 13%, respectively. (Table 1). Conclusions: BRAF + EGFR inhibitor combination is showing promising antitumor effects, and the addition of the FOLFIRI regimen was more effective than adding irinotecan alone while comparing treatment regimens in BRAF V600E-mutated CRC patients with metastasis. V+Co showed antitumor effects in CRC BRAF mutated patients who were heavily pre-treated. More randomized trials needed. [Table: see text]

Efficacy and safety of encorafenib-based regimens in colorectal cancer: A systematic review of clinical trials.

e15600 Background: BRAF gene mutation is present in 10% of the world’s 3rd common cancer, i.e., colorectal cancer (CRC). Constitutive activation of the mitogen-activated protein kinase pathway (MAPKP) results from this mutation, abnormal activation of MAPKP, inhibiting apoptosis and enhancing proliferative activity. In this systematic review, we will assess the efficacy of encorafenib (a BRAF inhibitor) based regimens in CRC. Methods: We followed PRISMA guidelines to conduct this systematic review. A literature search was performed on PubMed, Embase, and Clinicaltrials.gov with mesh terms, ‘’Colorectal Neoplasms’’ and “Proto-Oncogene Proteins B-raf” from the inception of data till 01/05/2023. We screened 4572 articles and included 1 randomized clinical trial (RCT, N = 665), and 4 non-randomized trials (nRCTs, N = 175), measuring the efficacy of encorafenib (E) based regimens in BRAF V600-mutated CRC. Results: In 4 clinical trials (N = 840), 246 patients treated with a double regimen and 373 treated with a triple regimen of E. In 2 clinical trials (N = 319), triple therapy of E + C + Binimetinib showed an overall response rate (ORR) of 47.8% and 26% in the untreated metastatic CRC (mCRC) and phase III randomized trial triple regimen arm, respectively. A recent trial on triple therapy of E + C + nivolumab (N) showed an ORR of 45% with overall survival (OS) and progression-free survival (PFS) of 11.4 and 7.3 months, respectively. In 1 randomized trial (N = 665), ORR improved from 2% in the control arm to 26% and 20% in triple and double regimens, respectively, which was mainly partial response (PR) with complete response (CR) of 4-5% in both groups. The OS was 9 and 8.4 months with a hazard ratio (HR) for death vs. control of 0.52; (95% confidence interval [CI], 0.39 to 0.70; P < 0.001) and 0.60; (95% CI, 0.45 to 0.79; P < 0.001) in the triple and dual regimen, respectively. In 1 trial of dose escalation study, alpelisib (A) was added to E + C and the addition of this third drug showed minimal changes in the ORR from 18 to 19%, and PFS improved from 3.7 to 4.2 months. (Table 1). Conclusions: A combination of BRAF inhibitors with anti-EGFR monoclonal antibodies showed a clinically significant increase in antitumor activity in BRAF-mutated mCRC compared to standard therapy. The addition of MEK/PI3K inhibitor as a third drug to E + C also showed some improvement in ORR and PFS. Triple therapy with E + C + N was also effective and tolerated well by the microsatellite stable (MSS) BRAF mutated mCRC population. Randomized trials are needed. [Table: see text]

Single-cell dissection reveals the role of DNA damage response patterns in tumor microenvironment components contributing to colorectal cancer progression and immunotherapy.

Colorectal cancer (CRC) is one of the leading malignant cancers. DNA damage response (DDR), referring to the molecular process of DNA damage, is emerging as a promising field in targeted cancer therapy. However, the engagement of DDR in the remodeling of the tumor microenvironment is rarely studied. In this study, by sequential nonnegative matrix factorization (NMF) algorithm, pseudotime analysis, cell-cell interaction analysis, and SCENIC analysis, we have shown that DDR genes demonstrate various patterns among different cell types in CRC TME (tumor microenvironment), especially in epithelial cells, cancer-associated fibroblasts, CD8+ T cells, tumor-associated macrophages, which enhance the intensity of intercellular communication and transcription factor activation. Furthermore, based on the newly identified DDR-related TME signatures, cell subtypes including MNAT+CD8+T_cells-C5, POLR2E+Mac-C10, HMGB2+Epi-C4, HMGB1+Mac-C11, PER1+Mac-C5, PER1+CD8+T_cells-C1, POLR2A+Mac-C1, TDG+Epi-C5, TDG+CD8+T_cells-C8 are determined as critical prognostic factors for CRC patients and predictors of immune checkpoint blockade (ICB) therapy efficacy in two public CRC cohorts, TCGA-COAD and GSE39582. Our novel and systematic analysis on the level of the single-cell analysis has revealed the unique role of DDR in remodeling CRC TME for the first time, facilitating the prediction of prognosis and guidance of personalized ICB regimens in CRC.

A meta-analysis of bevacizumab’s cardiovascular risks in patients treated for colorectal cancer.

113 Background: Bevacizumab (BVZ), a recombinant humanized monoclonal IgG antibody, is commonly used as first- and second-line adjuvant therapy in metastatic colorectal cancer. Recent guidelines have shown that a combination of three cytotoxic drug regimens FOLFOX (fluorouracil, leucovorin and oxaliplatin) along with BVZ is regarded as one of the first-line options. As we see an upward trend in using BVZ; it is crucial to analyze the side effects and potential toxicities. A frequent adverse effect with BVZ is hypertension. The prevailing hypothesis for the mechanism of BVZ induced hypertension is an increase in vascular tone due to the inhibition of VEGF-mediated vasodilation. A persistent elevation of arterial blood pressure is generally asymptomatic, but unmanaged hypertension can lead to cardiovascular complications, encephalopathy, and subarachnoid hemorrhage. Therefore, this meta-analysis aims to evaluate and assess the risk of BVZ induced hypertension. Methods: Our search included articles from PubMed, EMBASE, Web of Science, and Cochrane Library from 1980 to March 2022. Randomized controlled trials and clinical trials with BVZ as an add-on therapy mentioning cardiovascular side effects were included. Full analysis control group included various guideline directed chemotherapies and the subgroup analysis control group focused on FOLFOX therapy. A random-effects model was used with Review Manager, and a P value < 0.05 was considered significant. Results: We included a total of 17,807 patients in our study with an average age of 65 years. Analysis pooled from 19 RCTs showed that the odds of hypertension (Grade 3 or more) in patients treated with BVZ were about four times higher than the control group (OR 3.82, 95% CI 3.35-4.36, p-value < 0.00001, I2 = 78%). In a subgroup analysis, BVZ was compared with FOLFOX group, with odds of hypertension (Grade 3 or more) in BVZ group being about five times higher than in FOLFOX group (OR 5.24, 95% CI 4.06-6.77, p-value < 0.00001, I2 = 58%). Conclusions: Our meta-analysis demonstrates a significant cardiovascular risk of Bevacizumab when added to the standard regime for advanced colorectal cancer treatment. When BVZ was used as an add-on therapy to FOLFOX regimens for colorectal cancer, it was associated with about five times higher odds of developing hypertension (Grade 3 or more) in the treatment group with BVZ. Previous RCTs have demonstrated that BVZ add-on therapy to the standard regime is safe and without significant risk of toxicity. Our findings are important as they give vital information in assessing the risk-benefit ratio of adding BVZ, especially in a population with vascular comorbidities. Now that we have established the statistical significance of hypertensive risk with BVZ, it will be interesting to see how these events can be prevented in patients treated for metastatic colorectal cancer. Dedicated RCTs are needed to confirm these findings.

Antitumor activities of a defucosylated anti‑EpCAM monoclonal antibody in colorectal carcinoma xenograft models.

Epithelial cell adhesion molecule (EpCAM) is a typeI transmembrane glycoprotein, which is highly expressed on tumor cells. As EpCAM plays a crucial role in cell adhesion, survival, proliferation, stemness, and tumorigenesis, it has been considered as a promising target for tumor diagnosis and therapy. Anti‑EpCAM monoclonal antibodies (mAbs) have been developed and have previously demonstrated promising outcomes in several clinical trials. An anti‑EpCAM mAb, EpMab‑37 (mouse IgG1, kappa) was previously developed by the authors, using the cell‑based immunization and screening method. In the present study, a defucosylated version of anti‑EpCAM mAb (EpMab‑37‑mG2a‑f) was generated to evaluate the antitumor activity against EpCAM‑positive cells. EpMab‑37‑mG2a‑f recognized EpCAM‑overexpressing CHO‑K1 (CHO/EpCAM) cells with a moderate binding‑affinity [dissociation constant (KD)=2.2x10‑8 M] using flow cytometry. EpMab‑37‑mG2a‑f exhibited potent antibody‑dependent cellular cytotoxicity (ADCC) and complement‑dependent cytotoxicity (CDC) for CHO/EpCAM cells by murine splenocytes and complements, respectively. Furthermore, the administration of EpMab‑37‑mG2a‑f significantly suppressed CHO/EpCAM xenograft tumor development compared with the control mouse IgG. EpMab‑37‑mG2a‑f also exhibited a moderate binding‑affinity (KD=1.5x10‑8M) and high ADCC and CDC activities for a colorectal cancer cell line (Caco‑2 cells). The administration of EpMab‑37‑mG2a‑f to Caco‑2 tumor‑bearing mice significantly suppressed tumor development compared with the control. By contrast, EpMab‑37‑mG2a‑f never suppressed the xenograft tumor growth of Caco‑2 cells in which EpCAM was knocked out. On the whole, these results indicate that EpMab‑37‑mG2a‑f may exert antitumor activities against EpCAM‑positive cancers and may thus be a promising therapeutic regimen for colorectal cancer.

Biomarkers in the development of individualized treatment regimens for colorectal cancer.

Colorectal cancer (CRC) is the third most common and second most deadly malignancy in the world with an estimated 1. 9 million cases and 0.9 million deaths in 2020. The 5-year overall survival for stage I disease is 92% compared to a dismal 11% in stage IV disease. At initial presentation, up to 35% of patients have metastatic colorectal cancer (mCRC), and 20-50% of stage II and III patients eventually progress to mCRC. These statistics imply both that there is a proportion of early stage patients who are not receiving adequate treatment and that we are not adequately treating mCRC patients. Targeted therapies directed at CRC biomarkers are now commonly used in select mCRC patients. In addition to acting as direct targets, these biomarkers also could help stratify which patients receive adjuvant therapies and what types. This review discusses the role of RAS, microsatellite instability, HER2, consensus molecular subtypes and ctDNA/CTC in targeted therapy and adjuvant chemotherapy. Given the relatively high recurrence rate in early stage CRC patients as well as the continued poor survival in mCRC patients, additional work needs to be done beyond surgical management to limit recurrence and improve survival. Biomarkers offer both a potential target and a predictive method of stratifying patients to determine those who could benefit from adjuvant treatment.

A Novel Protein Encoded by Exosomal CircATG4B Induces Oxaliplatin Resistance in Colorectal Cancer by Promoting Autophagy.

Oxaliplatin is commonly used in chemotherapeutic regimens for colorectal cancer (CRC) after surgical resection. However, acquired chemoresistance seriously affects the curative effect in CRC patients, and the mechanism is still unclear. Here, a circular RNA, circATG4B is identified, which plays an important role in oxaliplatin resistance in CRC. circATG4B expression is found to be increased in exosomes secreted by oxaliplatin-resistant CRC cells. In addition, the results suggest that circATG4B induces oxaliplatin resistance by promoting autophagy. Further in vivo and in vitro studies indicate that the effect of circATG4B is attributed to its potential to encode a novel protein, circATG4B-222aa. Next, circATG4B-222aa is found to function as a decoy to competitively interact with TMED10 and prevent TMED10 from binding to ATG4B, which leads to increased autophagy followed by induction of chemoresistance. Therefore, this study reveals that exosomal circATG4B participates in the decreased chemosensitivity of CRC cells, providing a new rationale for a potential therapeutic target for oxaliplatin resistance in CRC.

Augmented Antitumor Effect of Unripe Rubus coreanus Miquel Combined with Oxaliplatin in a Humanized PD-1/PD-L1 Knock-In Colorectal Cancer Mouse Model.

Immune checkpoint inhibitors (ICIs) have been shown to be extraordinarily effective in patients with colorectal cancer (CRC). However, the current ICIs still have adverse effects and limited efficacy of ICI monotherapy. We used a natural product to overcome the vulnerability of ICIs and tried a combination therapy with oxaliplatin to enhance the programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) blockade anticancer effect. In the present study, we evaluated the T cell-mediated antitumor immunity with Unripe Rubus coreanus Miquel extract (RCE), which exerts anticancer properties via PD-1/PD-L1 blockade, combined with oxaliplatin in a co-culture cell model and allograft tumor humanized PD-1 mice. We found that RCE plus oxaliplatin apparently activates hPD-1 tumor-infiltrating CD8+ T cells, resulting in elevations of released interleukin-2 (IL-2) and granzyme B (GrB), and kills hPD-L1 MC38 CRC cells. RCE plus oxaliplatin considerably reduced tumor growth in humanized PD-1/PD-L1-expressing mouse MC38 CRC allograft. Moreover, RCE plus oxaliplatin remarkably increased the infiltration of CD8+ T cells in tumor tissues, as well as increasingly produced GrB of tumor-infiltrating CD8+ T cells in the tumor microenvironment. Our study delineated combination therapy with RCE as a PD-1/PD-L1 blockade and oxaliplatin to improve the response to immune checkpoint blockade therapy in conjunction with standard chemotherapy regimens in CRC.