PTPLAD1 Regulates PHB-Raf Interaction to Orchestrate Epithelial-Mesenchymal and Mitofusion-Fission Transitions in Colorectal Cancer

Colorectal cancer (CRC) remains one of the leading causes of cancer-related death worldwide. The poor prognosis of this malignancy is attributed mainly to the persistent activation of cancer signaling for metastasis. Here, we showed that protein tyrosine phosphatase-like A domain containing 1 (PTPLAD1) is down-regulated in highly metastatic CRC cells and negatively associated with poor survival of CRC patients. Systematic analysis reveals that epithelial-to-mesenchymal transition (EMT) and mitochondrial fusion-to-fission (MFT) transition are two critical features for CRC patients with low expression of PTPLAD1. PTPLAD1 overexpression suppresses the metastasis of CRC in vivo and in vitro by inhibiting the Raf/ERK signaling-mediated EMT and mitofission. Mechanically, PTPLAD1 binds with PHB via its middle fragment (141-178 amino acids) and induces dephosphorylation of PHB-Y259 to disrupt the interaction of PHB-Raf, resulting in the inactivation of Raf/ERK signaling. Our results unveil a novel mechanism in which Raf/ERK signaling activated in metastatic CRC induces EMT and mitochondrial fission simultaneously, which can be suppressed by PTPLAD1. This finding may provide a new paradigm for developing more effective treatment strategies for CRC.

Co-inhibition of TGF-β and PD-L1 pathways in a metastatic colorectal cancer mouse model triggers interferon responses, innate cells and T cells, alongside metabolic changes and tumor resistance

Colorectal cancer (CRC) is the third most prevalent cancer worldwide with a high mortality rate (20-30%), especially due to metastasis to adjacent organs. Clinical responses to chemotherapy, radiation, targeted and immunotherapies are limited to a subset of patients making metastatic CRC (mCRC) difficult to treat. To understand the therapeutic modulation of immune response in mCRC, we have used a genetically engineered mouse model (GEMM), "KPN", which resembles the human 'CMS4'-like subtype. We show here that transforming growth factor (TGF-β1), secreted by KPN organoids, increases cancer cell proliferation, and inhibits splenocyte activation in vitro. TGF-β1 also inhibits activation of naive but not pre-activated T cells, suggesting differential effects on specific immune cells. In vivo, the inhibition of TGF-β inflames the KPN tumors, causing infiltration of T cells, monocytes and monocytic intermediates, while reducing neutrophils and epithelial cells. Co-inhibition of TGF-β and PD-L1 signaling further enhances cytotoxic CD8+T cells and upregulates innate immune response and interferon gene signatures. However, simultaneous upregulation of cancer-related metabolic genes correlated with limited control of tumor burden and/or progression despite combination treatment. Our study illustrates the importance of using GEMMs to predict better immunotherapies for mCRC.

CDK12 is a potential biomarker for diagnosis, prognosis and immunomodulation in pan-cancer

Cell cycle-dependent protein kinase 12 (CDK12) plays a key role in a variety of carcinogenesis processes and represents a promising therapeutic target for cancer treatment. However, to date, there have been no systematic studies addressing its diagnostic, prognostic and immunological value across cancers. Here, we found that CDK12 was significantly upregulated in various types of cancers, and it expression increased with progression in ten cancer types, including breast cancer, cholangiocarcinoma and colon adenocarcinoma. Moreover, the ROC curves indicated that CDK12 showed diagnostic value in eight cancer types. High CDK12 expression was associated with poor prognosis in eight types of cancer, including low-grade glioma, mesothelioma, melanoma and pancreatic cancer. Furthermore, we conducted immunoassays to explore the exact mechanisms underlying CDK12-induced carcinogenesis, which revealed that increased expression of CDK12 allowed tumours to evade immune surveillance and upregulate immune checkpoint genes. Additionally, mutational studies have shown that amplification and missense mutations are the predominant mutational events affecting CDK12 across cancers. These findings establish CDK12 as a significant biological indicator of cancer diagnosis, prognosis, and immunotherapeutic targeting. Early surveillance and employment of CDK12 inhibitors, along with concomitant immunotherapy interventions, may enhance the clinical outcomes of cancer patients.

Modified FOLFOX6 plus bevacizumab with and without nivolumab for first-line treatment of metastatic colorectal cancer: phase 2 results from the CheckMate 9X8 randomized clinical trial

BACKGROUND

Standard first-line therapies for metastatic colorectal cancer (mCRC) include fluoropyrimidine-containing regimens with oxaliplatin and/or irinotecan and a biologic agent. Immunotherapy may enhance antitumor activity in combination with standard therapies in patients with mCRC. Here, we present phase 2 results of nivolumab plus standard-of-care therapy (SOC; 5-fluorouracil/leucovorin/oxaliplatin/bevacizumab) versus SOC in the first-line treatment of patients with mCRC (CheckMate 9X8).

METHODS

CheckMate 9X8 was a multicenter, open-label, randomized, phase 2/3 trial. Eligible patients were at least 18 years of age with unresectable mCRC and no prior chemotherapy for metastatic disease. Patients were randomized 2:1 to receive nivolumab 240 mg plus SOC or SOC alone every 2 weeks. The primary endpoint was progression-free survival (PFS) by blinded independent central review (BICR) per Response Evaluation Criteria in Solid Tumors V.1.1. Secondary endpoints included PFS by investigator assessment; objective response rate (ORR), disease control rate, duration of response, and time to response, all by BICR and investigator assessments; overall survival; and safety. Preplanned exploratory biomarker analyses were also performed.

RESULTS

From February 2018 through April 2019, 310 patients were enrolled, of which 195 patients were randomized to nivolumab plus SOC (n=127) or SOC (n=68). At 21.5-month minimum follow-up, PFS with nivolumab plus SOC versus SOC did not meet the prespecified threshold for statistical significance; median PFS by BICR was 11.9 months in both arms (HR, 0.81 (95% CI, 0.53 to 1.23); p=0.30). Higher PFS rates after 12 months (18 months: 28% vs 9%), higher ORR (60% vs 46%), and durable responses (median 12.9 vs 9.3 months) were observed with nivolumab plus SOC versus SOC. Grade 3-4 treatment-related adverse events were reported in 75% versus 48% of patients; no new safety signals were identified.

CONCLUSIONS

The CheckMate 9X8 trial investigating first-line nivolumab plus SOC versus SOC in patients with mCRC did not meet its primary endpoint of PFS by BICR. Nivolumab plus SOC showed numerically higher PFS rates after 12 months, a higher response rate, and more durable responses compared with SOC alone, with acceptable safety. Further investigation to identify subgroups of patients with mCRC that may benefit from nivolumab plus SOC versus SOC in the first-line setting is warranted.

TRIAL REGISTRATION NUMBER

NCT03414983.

Unraveling the causal role of immune cells in gastrointestinal tract cancers: insights from a Mendelian randomization study

Background

Despite early attempts, the relationship between immune characteristics and gastrointestinal tract cancers remains incompletely elucidated. Hence, rigorous and further investigations in this domain hold significant clinical relevance for the development of novel potential immunotherapeutic targets.

Methods

We conducted a two-sample Mendelian randomization (MR) analysis using the tools available in the "TwoSampleMR" R package. The GWAS data for these 731 immune traits were sourced from the GWAS Catalog database. Concurrently, data on gastrointestinal tract cancers, encompassing malignant tumors in the esophagus, stomach, small intestine, colon, and rectum, were extracted from the FinnGen database. The immune traits subjected to MR analysis predominantly fall into four categories: median fluorescence intensities (MFI), relative cell (RC), absolute cell (AC), and morphological parameters (MP). To ensure the reliability of our findings, sensitivity analyses were implemented to address robustness, account for heterogeneity, and alleviate the impact of horizontal pleiotropy.

Results

A total of 78 immune traits causally linked to gastrointestinal tract cancers were identified, encompassing esophageal cancer (12 traits), gastric cancer (13 traits), small intestine cancer (22 traits), colon cancer (12 traits), and rectal cancer (19 traits). Additionally, 60 immune traits were recognized as protective factors associated with gastrointestinal tract cancers, distributed across esophageal cancer (14 traits), gastric cancer (16 traits), small intestine cancer (7 traits), colon cancer (14 traits), and rectal cancer (9 traits). Furthermore, it was observed that seven immune traits are causally related to gastrointestinal tract cancers in at least two locations. These traits include "CCR2 on CD14- CD16+ monocyte," "CD19 on IgD+ CD38-," "CD19 on IgD+ CD38- naive," "CD25hi CD45RA+ CD4 not Treg AC," "CD27 on unsw mem," "CD28 on CD39+ activated Treg," and "CD45 on CD4+."

Conclusion

This study elucidates a causal link between immune cells and gastrointestinal tract cancers at various sites through genetic investigation. The findings of this research open up new perspectives and resources for exploring tumor prevention strategies and immunotherapeutic targets.

Organometallic Ru(II), Rh(III) and Re(I) complexes of sterane-based bidentate ligands: synthesis, solution speciation, interaction with biomolecules and anticancer activity

In this study, we present the synthesis, characterization and in vitro cytotoxicity of six organometallic [Ru(II)(η6-p-cymene)(N,N)Cl]Cl, [Rh(III)(η5-C5Me5)(N,N)Cl]Cl and [Re(I)(CO)3(N,N)Cl] complexes, in which the (N,N) ligands are sterane-based 2,2'-bipyridine derivatives (4-Me-bpy-St-OH, 4-Ph-bpy-St-OH). The solution chemical behavior of the ligands and the complexes was explored by UV-visible spectrophotometry and 1H NMR spectroscopy. The ligands and their Re(I) complexes are neutral at pH = 7.40; this contributes to their highly lipophilic character (log D7.40 > +3). The Ru(II) and Rh(III) half-sandwich complexes are much more hydrophilic, and this property is greatly affected by the actual chloride ion content of the medium. The half-sandwich Ru and Rh complexes are highly stable in 30% (v/v) DMSO/water (<5% dissociation at pH = 7.40); this is further increased in water. The Rh(III)(η5-C5Me5) complexes were characterized by higher water/chloride exchange and pKa constants compared to their Ru(II)(η6-p-cymene) counterparts. The Re(I)(CO)3 complexes are also stable in solution over a wide pH range (2-12) without the release of the bidentate ligand; only the chlorido co-ligand can be replaced with OH- at higher pH values. A comprehensive discussion of the binding affinity of the half-sandwich Ru(II) and Rh(III) complexes toward human serum albumin and calf-thymus DNA is also provided. The Ru(II)(η6-p-cymene) complexes interact with human serum albumin via intermolecular forces, while for the Rh(III)(η5-C5Me5) complexes the coordinative binding mode is suggested as well. They are also able to interact with calf-thymus DNA, most likely via the coordination of the guanine nitrogen. The Ru(II)(η6-p-cymene) complexes were found to be the most promising among the tested compounds as they exhibited moderate-to-strong cytotoxic activity (IC50 = 3-11 μM) in LNCaP as well as in PC3 prostate cells in an androgen receptor-independent manner. They were also significantly cytotoxic in breast and colon adenocarcinoma cancer cell lines and showed good selectivity for cancer cells.

Prognostic significance and immunological role of HPRT1 in human cancers

Hypoxanthine phosphoribosyl transferase 1 (HPRT1), once considered a housekeeping gene, has been identified as playing an important role in several tumors. Its role in pan-cancer, however, has not been systematically studied. This study evaluates the relationship between HPRT1 and clinical parameters, survival prognosis, and tumor immunity based on multi omics data from the Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Drug sensitivity analysis screened 16 effective drugs against HPRT1, exploring the interactions with chemicals and genes. The significance of HPRT1 in tumor immunotherapy has also been investigated. Immunohistochemistry confirmed significant differences in the expression of HPRT1 between five tumor types (colon adenocarcinoma [COAD], head-neck squamous cell carcinoma [HNSC], lung adenocarcinoma [LUAD], thyroid carcinoma [THCA], and uterine corpus endometrial carcinoma [UCEC]) and adjacent normal tissues (P < 0.05). HPRT1 competitive endogenous RNA network was constructed in HNSC. Through cytological experiments, it was verified that HPRT1 plays a carcinogenic role in HNSC and is associated with tumor cell proliferation, migration, invasion, and apoptosis. In addition, there was a significant positive correlation between HPRT1 and programmed cell death-1 (PD-1) expression in HNSC (P < 0.05). These findings suggest that HPRT1 may be a potential biomarker for predicting and treating cancer.

Exploring the potential biological function of GRK2 in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a malignant tumor of the gastrointestinal tract with high morbidity and mortality. There is growing evidence that GRK2 plays a key role in the development and progression of several human cancers. However, the role and potential mechanisms of GRK2 in colon cancer (COAD) are unclear.

METHODS

The expression data of GRK2 was downloaded from The Cancer Genome Atlas database (TCGA). Variation in GRK2 was explored based on the cBioPortal database. The TIMER and TISCH2 databases were used to analyse the relationship between GRK2 expression and tumor immune microenvironment (TME). A log-rank test was used to compare the prognosis of high and low expression of GRK2 groups. Detecting the effect of GRK2 on cell cycle and apoptosis induced by 5-Fluorouracil (5-FU) through the flow cytometry and detection of apoptosis-related molecules by Western blot.

RESULTS

We demonstrated that GRK2 has a potential oncogenic role. GRK2 expression was upregulated in COAD, which predicted poorer overall survival in COAD patients. The cellular assays showed that GRK2 plays a role in the growth and proliferation of colon cancer cells, also the expression of GRK2 have relationship with the sensitivity of 5-FU and cell cycle progression.

CONCLUSIONS

Our results suggest that high GRK2 expression is closely associated with the development of tumor and affects the 5-FU sensitivity.

Chemotherapy re-use versus anti-angiogenic monotherapy as the third-line treatment of patients with metastatic colorectal cancer: a real-world cohort study

BACKGROUND

There are various recommendations for third-line treatment in mCRC, however, there is no consensus on who is more suitable for particular strategy. Chemotherapy re-use in third-line setting is a common option in clinical practice. This study aimed to investigate the efficacy of third-line chemotherapy re-use by the comparison with that of anti-angiogenic monotherapy, and further find the population more suitable for third-line chemotherapy.

METHODS

Using electronic medical records of patients with mCRC, a retrospective cohort study was conducted. A total of 143 patients receiving chemotherapy and 40 patients receiving anti-angiogenic monotherapy in third-line setting as control group were retrospectively collected. Baseline characteristics were analyzed using the χ² test or the Fisher's exact test. ROC curve and surv_cutpoint function of 'survminer' package in R software were used to calculate the cut-off value. Survival curves were plotted with the Kaplan-Meier method and were compared using the log-rank test. The Cox proportional hazard regression model was used to analyze the potential risk factors.

RESULTS

A total of 143 patients receiving chemotherapy and 40 patients receiving anti-angiogenic monotherapy in third-line setting were retrospectively collected. Chemotherapy rechallenge was recorded in 93 patients (93/143, 65.0%), and the remaining patients chose new chemotherapeutic drugs that had not been previously used, including irinotecan-based (22/50), oxaliplatin-based (9/50), raltitrexed (9/50), gemcitabine (5/50) and other agents (5/50). The ORR and DCR of third-line chemotherapy reached 8.8%, 61.3%, respectively (anti-angiogenic monotherapy group: ORR 2.6%, DCR 47.4%). The mPFS and mOS of patients receiving chemotherapy were 4.9 and 12.0 m, respectively (anti-angiogenic monotherapy group: mPFS 2.7 m, mOS 5.2 m). Subgroup analyses found that patients with RAS/RAF mutation, longer PFS (greater than 10.6 m) in front-line treatment or larger tumor burden had better prognosis with third-line chemotherapy rather than anti-angiogenic monotherapy.

CONCLUSIONS

Third-line chemotherapy re-use was effective in mCRC. Those with more aggressive characteristics (RAS/RAF mutant, larger tumor burden) or better efficacy of previous chemotherapy (longer PFS) were more appropriate for third-line chemotherapy, rather than anti-angiogenic monotherapy.

Loss of RAS Mutations in Liquid Biopsies of Patients With Multi-Treated Metastatic Colorectal Cancer

BACKGROUND

Liquid biopsy (LB) is a non-invasive tool to evaluate the heterogeneity of tumors. Since RAS mutations (RAS-mut) play a major role in resistance to antiepidermal growth factor receptor inhibitors (EGFR) monoclonal antibodies (Mabs), serial monitoring of RAS-mut with LB may be useful to guide treatment. The main aim of this study was to evaluate the prognostic value of the loss of RAS-mut (NeoRAS-wt) in LB, during the treatment of metastatic colorectal cancer (mCRC).

METHODS

A retrospective study was conducted on patients with mCRC between January 2018 and December 2021. RAS-mut were examined in tissue biopsy, at mCRC diagnosis, and with LB, during treatment.

RESULTS

Thirty-nine patients with RAS-mut mCRC were studied. LB was performed after a median of 3 lines (0-7) of systemic treatment including anti-vascular endothelial growth factor (anti-VEGF) Mabs. NeoRAS-wt was detected in 13 patients (33.3%); 9 (69.2%) of them received further treatment with anti-EGFR Mabs with a disease control rate of 44.4%. Median overall survival (OS), from the date of LB testing, was 20 months in the NeoRAS-wt group and 9 months in the persistent RAS-mut group (log-rank 2.985; P = .08), with a 12-month OS of 84.6% and 57.7%, respectively. NeoRAS-wt was identified as a predictor of survival (HR = 0.29; P = .007), with an 11-month improvement in median OS and a 71% decrease in risk of death, in heavily pretreated patients.

CONCLUSIONS

In conclusion, monitoring clonal evolution in mCRC by LB may provide an additional treatment line for patients with NeoRAS-wt in advanced disease.

Surgical quality assessment for the prospective study of oncologic outcomes after laparoscopic modified complete mesocolic excision for nonmetastatic right colon cancer (PIONEER study)

BACKGROUND

The modified complete mesocolic excision (mCME) procedure for right-sided colon cancer is a tailored approach based on the original complete mesocolic excision (CME) methodology. Limited studies evaluated the safety and feasibility of laparoscopic mCME using objective surgical quality assessments in patients with right colon cancer. The objectives of the PIONEER study were to evaluate oncologic outcomes after laparoscopic mCME and to identify optimal clinically relevant endpoints and values for standardizing laparoscopic right colon cancer surgery based on short-term outcomes of procedures performed by expert laparoscopic surgeons.

MATERIALS AND METHODS

This is an ongoing prospective, multi-institutional, single-arm study conducted at five tertiary colorectal cancer centers in South Korea. Study registrants included 250 patients scheduled for laparoscopic mCME with right-sided colon adenocarcinoma (from the appendix to the proximal half of the transverse colon). The primary endpoint was 3-year disease-free survival. Secondary outcomes included 3-year overall survival, incidence of morbidity in the first 4 weeks postoperatively, completeness of mCME, central radicality, and distribution of metastatic lymph nodes. Survival data will be available after the final follow-up date (June 2024).

RESULTS

The postoperative complication rate was 12.9%, with a major complication rate of 2.7%. In 87% of patients, central radicality was achieved with dissection at or beyond the level of complete exposure of the superior mesenteric vein. Mesocolic plane resection with an intact mesocolon was achieved in 75.9% of patients, as assessed through photographs. Metastatic lymph node distribution varied by tumor location and extent. Seven optimal clinically relevant endpoints and values were identified based on the analysis of complications in low-risk patients.

CONCLUSIONS

Laparoscopic mCME for right-sided colon cancer produced favorable short-term postoperative outcomes. The identified optimal clinically relevant endpoints and values can serve as a reference for evaluating surgical performance of this procedure.

Complete mesocolic excision for colon cancer: current status and controversies

According to Hohenberger's original description, complete mesocolic excision for colon cancer involves precise dissection of the avascular embryonic plane between the parietal retroperitoneum and visceral peritoneum of the mesocolon. This ensures mesocolic integrity, access to high ligation of the supplying vessels at their origin and an associated extended lymphadenectomy. Results from centres which have adopted this approach routinely have demonstrated that oncological outcomes can be improved by the rigorous implementation of established principles of cancer surgery. Meticulous anatomical dissection along embryonic planes is a well-established principle of precision cancer surgery used routinely by the specialist colorectal surgeon. Therefore, the real question concerns the need for true central vascular ligation and associated extended (D3) lymphadenectomy or otherwise, particularly along the superior mesenteric vessels when performing a right colectomy. Whether this approach results in improved overall or disease-free survival remains unclear and its role remains controversial particularly given the potential for significant morbidity associated with a more extensive central vascular dissection. Current literature is limited by considerable bias, as well as inconsistent and variable terminology, and the results of established randomized trials are awaited. As a result of the current state of equipoise, various national guidelines have disparate recommendations as to when complete mesocolic excision should be performed if at all. This article aims to review the rationale for and technical aspects of complete mesocolic excision, summarize available short and long term outcome data and address current controversies.

Cyclic Amines Coupled to Indole Derivatives With Improved Efflux Pump Inhibiting Activity in Bacteria and Cancer Cells

BACKGROUND/AIM

Indole skeleton has become a significant tool in the field of anticancer and antibacterial therapeutic strategies. The modified aza-Friedel-Crafts reaction by direct coupling of different cyclic imines and indole derivatives has been explored. To investigate the scope and limitations of the reaction and observe the effect of structural modifications, our aim was to resynthesize selected compounds as well as prepare new derivatives starting from 6,7-dimethoxy-3,4-dihydroisoquinoline, (4aR,8aR)-4a,5,6,7,8,8a-hexahydroquinoxalin-2(1H)-one and 7-azaindole. Our further aim was the systematic biological evaluation of selected C-3-coupled indole and azaindole derivatives in favour of having a preliminary overview about the structure-activity relationships.

MATERIALS AND METHODS

The synthesis and resynthesis of selected compounds were accomplished by extension of aza-Friedel-Crafts reaction. The products have been tested on bacteria and cancer cells.

RESULTS

The most significant efflux pump inhibiting (EPI) activity was observed in the case of 6,7-dihydrothieno[3,2-c]pyridine coupled indole derivative. The reaction of 6,7-dimethoxy-3,4-dihydroisoquinoline with 7-azaindole resulted in the most potent biofilm inhibitor product. Applying indole and 4,9-dihydro-3H-β-carboline, 6,7-dihydrothieno[3,2-c]pyridine led to the formation of a product with the highest anticancer activity. 6,7-Dimethoxy-3,4-dihydroisoquinoline skeleton and indole as an electron-rich aromatic compound have been found to be effective in the inhibition of ABCB1.

CONCLUSION

The compounds presented in the study were investigated regarding different aspects of antibacterial and anticancer activities. Accordingly, some compounds were found to have antibacterial effect on Escherichia coli and Staphylococcus aureus strains, certain C-3-coupled derivatives showed toxicity on sensitive and ABCB1 efflux pump expressing colon adenocarcinoma and a normal, non-cancerous fibroblast cell lines.

Pirin Inhibits FAS-Mediated Apoptosis to Support Colorectal Cancer Survival

Resistance to immunotherapy in colorectal cancer (CRC) is associated with obstruction of FAS (Apo-1 or CD95)-dependent apoptosis, a hallmark of cancer. Here it is demonstrated that the upregulation of pirin (PIR) protein in colon cancers promotes tumorigenesis. Knockout or inhibition of PIR dramatically increases FAS expression, FAS-dependent apoptosis and attenuates colorectal tumor formation in mice. Specifically, NFκB2 is a direct transcriptional activator of FAS and robustly suppressed by PIR in dual mechanisms. One is the disruption of NFκB2 complex (p52-RELB) association with FAS promoter, the other is the inhibition of NIK-mediated NFκB2 activation and nuclear translocation, leading to the inability of active NFκB2 complex toward the transcription of FAS. Furthermore, PIR interacts with FAS and recruits it in cytosol, preventing its membrane translocation and assembling. Importantly, knockdown or knockout of PIR dramatically sensitizes cells to FAS mAb- or active CD8+ T cells-triggered cell death. Taken together, a PIR-NIK-NFκB2-FAS survival pathway is established, which plays a key role in supporting CRC survival.

Racial Differences in Stage IV Colorectal Cancer Molecular Profiling and Mutation Rates

INTRODUCTION

Despite advances in colorectal cancer (CRC) treatment, racial disparities persist. The primary aims of the study were to: evaluate differences in molecular testing rates over time by race; and measure the incidence of tumor mutations by race in patients with metastatic CRC.

METHODS

A retrospective cohort study was performed of all adult patients with stage IV CRC (2008-2018) identified within the cancer registry of a large regional health system. Demographic/clinical characteristics were collected through primary data abstraction of the electronic health record. Molecular profiling results were obtained directly from Caris Molecular Intelligence and electronic health record.

RESULTS

Three hundred eighty-three patients were included: 40.5% (n = 155) were Black and 59.5% (n = 228) were White. Significant increases were observed in microsatellite instability (MSI), KRAS, and BRAF testing rates during the study period (P < 0.0001). The odds of testing over time increased more significantly in Black compared to White patients for MSI testing (White: odds ratio [OR] 1.26 [95% confidence interval [CI] 1.12-1.41], Black: OR 1.69 [95% CI 1.41-2.02], P = 0.005) and BRAF testing (White: OR 1.42 [95% CI 1.26-1.62], Black: OR 1.89 [95% CI 1.51-2.36], P = 0.027). An increase in KRAS testing over time was observed for both cohorts and was independent of race (P = 0.58). Mutation rates did not differ by race: KRAS (Black 55.8% versus White 45.6%, P = 0.13) and BRAF (Black 4.8% versus White 10.0%, P = 0.33).

CONCLUSIONS

Within a large regional health system, molecular testing rates in patients with metastatic CRC increased significantly following National Comprehensive Cancer Network guideline changes for both Black and White patients. Black and White patients who underwent molecular testing had similar rates of MSI, KRAS, and BRAF mutations.

Genetic specificity study using next-generation sequencing (NGS) of peritoneal metastatic colorectal cancer compared to primary colorectal cancer

BACKGROUND

In patients with colorectal cancer, peritoneal metastases are the second most frequent metastatic lesion after liver metastases. Peritoneal metastases have a very poor prognosis, with a median survival time of 5-7 months. Currently, there is a lack of research on the genetic differences between primary colorectal cancer and peritoneal metastases. Therefore, we aimed to identify their genetic characteristics through a cancer panel test using next-generation sequencing.

OBJECTIVE

We aim to investigate the specificity of genetic variants in primary colorectal cancer and peritoneal metastases.

METHODS

We recruited patients with stage I, II, and III primary colorectal cancer and peritoneal metastases for genetic analysis using NGS. Samples were collected from patients who underwent surgery at Dankook University Hospital and consented to genetic testing. NGS was performed using a cancer panel.

RESULTS

Among 36 patients with primary cancer, TP53 gene mutation was identified the most in 25 patients (69%), followed by APC gene mutation in 19 patients (53%), and KRAS gene mutation in 17 patients (47%). In the peritoneal metastasis patient group, unlike the primary cancer patient group, KRAS gene mutations were the most common 6 patients (55%), followed by TP53 gene mutations in 4 patients (36%) and PIK3CA gene mutations in 2 patients (18%).

CONCLUSION

The small number of surgical cases of peritoneal metastases was a limitation of our sample size. Nevertheless, we identified differences in the alterations of specific genes between primary and peritoneal metastases. Acquiring additional cases and collecting more data will provide deeper insights into these cancers.

Curcumin activates the JNK signaling pathway to promote ferroptosis in colon cancer cells

Recent evidence has proved that curcumin as a natural polyphenol have a great anticancer and anti-proliferative effects in cancer cells. Ferroptosis, a new form of regulated cell death, plays a vital role in the pathogenesis and therapy of cancers. In this study, we aimed to examine the effects of curcumin in ferroptosis of human colorectal cancer cells and its underlying molecular mechanisms. SW-480 colorectal cancer cells were treated by curcumin with different concentrations. Cell viability was determined by using MTT assay. The concentrations of reactive oxygen species (ROS) and intracellular iron were measured using specific related kits. Real-time PCR and Western blot analysis were used to determine the expression of ferroptosis-related proteins including ACSL4, GPx4 and FTH1 and activation of JNK protein. Curcumin suppressed SW-480 cancer cells viability in dose-dependent manner. Cell treatment with curcumin led to accumulation of ROS and iron within cells and increase in the intracellular levels of lipid peroxidation. In addition, curcumin modulated the mRNA and protein expression levels of ferroptosis-related proteins including ACSL4, GPx4 and FTH1 and suppression of JNK signaling. Curcumin may exhibit its anticancer effect on colorectal cancer by downregulating JNK signaling to induce ferroptosis in SW-480 cells.

Long-term Outcomes of Robot-assisted Versus Laparoscopic Surgery for Colon Cancer: A Nationwide Register-based Cohort Study

OBJECTIVE

To determine long-term survival in patients undergoing robot-assisted surgery (RAS) or laparoscopic surgery (LAS) for colon cancer.

BACKGROUND

The potential long-term benefits of RAS compared with LAS for colon cancer are not well examined. Using a register-based approach, we aimed to compare these 2 surgical platforms in an analysis of long-term outcomes, including recurrence-free survival and all-cause- and colon cancer-specific mortality.

METHODS

A nationwide register-based cohort study of patients with Union for International Cancer Control stage I-III colon cancer undergoing planned RAS or LAS from 2010 through 2018. Patient demographic, clinical, and pathological data were retrieved from Danish national registers. Survival and recurrence rates were estimated by Cox proportional hazard multivariate regression analysis adjusting for baseline covariates.

RESULTS

A total of 7565 patients [LAS=6905 (91%) and RAS=660 (9%)] were included in the complete case survival analysis. Patients undergoing LAS had a significantly increased risk of cancer recurrence [LAS=1178 (17.1%), RAS=82 (12.4%), P =0.002] with a mean follow-up time of 4.93 years (standard deviation 2.47). The survival analysis of recurrence-free survival favored RAS [hazard ratio adjusted =0.80, 95% CI (0.64-1.00), P =0.049]. No associations between the 2 surgical platforms were evident regarding all-cause [hazard ratio adjusted =0.98, 95% CI (0.82-1.17), P =0.783] or colon cancer-specific mortality [hazard ratio adjusted =0.89, 95% CI (0.67-1.18), P =0.405].

CONCLUSIONS

Adopting RAS for colon cancer was associated with improved recurrence-free survival. However, it did not cause a lower all-cause- or colon cancer-specific mortality.

Visualizing External Validity: Graphical Displays to Inform the Extension of Treatment Effects from Trials to Clinical Practice

BACKGROUND

In the presence of effect measure modification, estimates of treatment effects from randomized controlled trials may not be valid in clinical practice settings. The development and application of quantitative approaches for extending treatment effects from trials to clinical practice settings is an active area of research.

METHODS

In this article, we provide researchers with a practical roadmap and four visualizations to assist in variable selection for models to extend treatment effects observed in trials to clinical practice settings and to assess model specification and performance. We apply this roadmap and visualizations to an example extending the effects of adjuvant chemotherapy (5-fluorouracil vs. plus oxaliplatin) for colon cancer from a trial population to a population of individuals treated in community oncology practices in the United States.

RESULTS

The first visualization screens for potential effect measure modifiers to include in models extending trial treatment effects to clinical practice populations. The second visualization displays a measure of covariate overlap between the clinical practice populations and the trial population. The third and fourth visualizations highlight considerations for model specification and influential observations. The conceptual roadmap describes how the output from the visualizations helps interrogate the assumptions required to extend treatment effects from trials to target populations.

CONCLUSIONS

The roadmap and visualizations can inform practical decisions required for quantitatively extending treatment effects from trials to clinical practice settings.

Efficacy of immune checkpoint inhibitors for metastatic colorectal cancer with microsatellite instability in second or latter line using synthetic control arms: A non-randomised evaluation

PURPOSE

Immune checkpoint inhibitors (ICIs) appeared active in single-arm trials for patients with chemoresistant metastatic colorectal cancer (mCRC) harboring microsatellite instability (MSI). Given the paucity of randomised controlled trials (RCTs) in this setting, we evaluated the effect size of ICIs using intra-patients comparison and ARCAD database as historical controls.

PATIENTS AND METHODS

Individual-patient data from NIPICOL and CheckMate 142 phase II trials that evaluated a combination of ICIs for MSI mCRC patients (N = 176) and from five non-ICI mCRC historical RCTs in second-line or latter (N = 4026) were analyzed. Firstly, promising of ICIs was identified using intra-patient comparison based on growth modulation index (GMI) defined the ratio of progression-free survivals (PFS) on ICIs and previous line of therapy. Survival outcomes of ICIs-treated patients were then compared with those matched non-ICIs treated from ARCAD database historical RCTs.

RESULTS

Among ICIs-treated patients, median PFS on ICIs was 32.66 (range 0.10-74.25) versus 4.07 months (range 0.7-49.87) on prior therapy, resulting on median GMI of 4.97 (range 0.07-59.51; hazard-ratio (HR)= 0.16 (95 %CI=0.11-0.22, P < 0.001)). Compared to matched non-ICI patients, in third-line, median overall survival (OS) was not reached with ICIs versus 3.52 months with placebo (HR=0.20, 95 %CI=0.10-0.41, P < 0.001), and 6.51 months with active drugs (HR=0.30, 95 %CI=0.15-0.60, P = 0.001). In second-line, median OS was not reached with ICIs versus 11.7 months with chemotherapy+placebo (HR=0.12, 95 %CI=0.07-0.22, P < 0.001), and 16.3 months with chemotherapy+targeted therapy (HR=0.10, 95 %CI=0.05-0.19, P < 0.001).

CONCLUSION

ICIs demonstrates high effect size for MSI mCRC patients in second-line and later. This work might be useful as an example of methodology to avoid RCTs when benefit from experimental therapy is likely to be high.

Prognostic Impact of Primary Tumor Sidedness in Stage III Colorectal Cancer: Real-World Evidence from a Brazilian Cohort

BACKGROUND

Primary tumor sidedness (PTS) is an independent prognostic factor in patients with metastatic colorectal cancer (CRC), with a worse prognosis for right-sided tumors. There are limited data on the prognostic impact of PTS in stage III CRC. The main objective of this study was to analyze the prognostic impact of PTS in stage III CRC.

PATIENTS AND METHODS

A retrospective and uni-institutional cohort study was performed in an oncology reference center. Patients with stage III CRC treated with a 5-fluorouracil and oxaliplatin-based chemotherapy regimen (mFLOX regimen) from October 2007 to February 2013 were included. The primary outcome was the probability of overall survival (OS) at 5 years stratified by PTS. Secondary outcomes were the probability of disease-free survival (DFS) at 5 years and an analysis of the prognostic impact of clinical and molecular biomarkers. Kaplan‒Meier curves were used, and Cox models were used to evaluate prognostic factors associated with OS and DFS.

RESULTS

Overall, 265 patients were evaluated. Transverse colon tumors, multicentric tumors, and undetermined primary subsites were excluded, resulting in 234 patients classified according to PTS: 95 with right sidedness (40.6%) and 139 with left sidedness (59.4%). The median follow-up time was 66 months [interquartile range (IQR): 39-81]. The 5-year OS probabilities for right-sided and left-sided tumors were 67% (95% CI: 58%-77%) and 82% (75%-89%), respectively [hazard ratio (HR): 2.02, 95% CI: 1.18-3.46; P = .010]. The 5-year probabilities of DFS for right-sided and left-sided tumors were 58% (49%-69%) and 65% (58%-74%), respectively (HR: 1.29, 0.84-1.97; P = 0.248).

CONCLUSION

These data suggest that there may be a worse prognosis (inferior OS at 5 years) for resected right-sided stage III CRC patients treated in the real world. However, these data need to be confirmed by prospective studies with a larger number of participants.

Nerolidol, Bioactive Compound Suppress Growth of HCT-116 Colorectal Cancer Cells Through Cell Cycle Arrest and Induction of Apoptosis

Colon cancer is the most prevalent cancer and causes the highest cancer-associated mortality in both men and women globally. It has a high incidence and fatality rate, which places a significant burden on the healthcare system. The current work was performed to understand the beneficial roles of nerolidol on the viability and cytotoxic mechanisms in the colon cancer HCT-116 cells. The MTT cytotoxicity assay was done to investigate the effect of nerolidol at different doses (5-100 µM) on the HCT-116 cell viability. The impacts of nerolidol on ROS accumulation and apoptosis were investigated using DCFH-DA, DAPI, and dual staining assays, respectively. The flow cytometry analysis was performed to study the influence of nerolidol on the cell cycle arrest in the HCT-116 cells. The outcomes of the MTT assay demonstrated that nerolidol at different doses (5-100 µM) substantially inhibited the HCT-116 cell viability with an IC50 level of 25 µM. The treatment with nerolidol appreciably boosted the ROS level in the HCT-116 cells. The findings of DAPI and dual staining revealed higher apoptotic incidences in the nerolidol-exposed HCT-116 cells, which supports its ability to stimulate apoptosis. The flow cytometry analysis demonstrated the considerable inhibition in cell cycle at the G0/G1 phase in the nerolidol-exposed HCT-116 cells. Our research showed that nerolidol can inhibit the cell cycle, increase ROS accumulation, and activate apoptosis in HCT-116 cells. In light of this, it may prove to be a potent and salutary candidate to treat colon cancer.