Replenishment of mitochondrial Na+ and H+ by ionophores potentiates cutaneous wound healing in diabetes.

Diabetic foot ulcer (DFU) is a highly morbid complication in patients with diabetes mellitus, necessitating the development of innovative pharmaceuticals to address unmet medical needs. Sodium ion (Na+) is a well-established mediator for membrane potential and osmotic equilibrium. Recently, Na+ transporters have been identified as a functional regulator of regeneration. However, the role of Na+ in the intricate healing process of mammalian wounds remains elusive. Here, we found that the skin wounds in hyponatremic mice display a hard-to-heal phenotype. Na+ ionophores that were employed to increase intracellular Na+ content could facilitate keratinocyte proliferation and migration, and promote angiogenesis, exhibiting diverse biological activities. Among of them, monensin A emerges as a promising agent for accelerating the healing dynamics of skin wounds in diabetes. Mechanistically, the elevated mitochondrial Na+ decelerates inner mitochondrial membrane fluidity, instigating the production of reactive oxygen species (ROS), which is identified as a critical effector on the monensin A-induced improvement of wound healing. Concurrently, Na+ ionophores replenish H+ to the mitochondrial matrix, causing an enhancement of mitochondrial energy metabolism to support productive wound healing programs. Our study unfolds a new role of Na+, which is a pivotal determinant in wound healing. Furthermore, it directs a roadmap for developing Na+ ionophores as innovative pharmaceuticals for treating chronic dermal wounds in diabetic patients.

Neoadjuvant chemotherapy is noninferior to chemoradiotherapy for early-onset locally advanced rectal cancer in the FOWARC trial.

BACKGROUND: The early-onset rectal cancer with rapidly increasing incidence is considered to have distinct clinicopathological and molecular profiles with high-risk features. This leads to challenges in developing specific treatment strategies for early-onset rectal cancer patients and questions of whether early-onset locally advanced rectal cancer (LARC) needs aggressive neoadjuvant treatment. METHODS: In this post hoc analysis of FOWARC trial, we investigated the role of preoperative radiation in early-onset LARC by comparing the clinicopathological profiles and short-term and long-term outcomes between the early-onset and late-onset LARCs. RESULTS: We revealed an inter-tumor heterogeneity of clinical profiles and treatment outcomes between the early-onset and late-onset LARCs. The high-risk features were more prevalent in early-onset LARC. The neoadjuvant radiation brought less benefits of tumor response and more risk of complications in early-onset group (pCR: OR = 3.75, 95% CI = 1.37-10.27; complications: HR = 11.35, 95% CI = 1.46-88.31) compared with late-onset group (pCR: OR = 5.33, 95% CI = 1.83-15.58; complications: HR = 5.80, 95% CI = 2.32-14.49). Furthermore, the addition of radiation to neoadjuvant chemotherapy didn't improve long-term OS (HR = 1.37, 95% CI = 0.49-3.87) and DFS (HR = 1.05, 95% CI = 0.58-1.90) for early-onset patients. CONCLUSION: Preoperative radiation plus chemotherapy may not be superior to the chemotherapy alone in the early-onset LARC. Our findings provide insight into the treatment of early-onset LARC by interrogating the aggressive treatment and alternative regimens.

Guide for phenotype-specific profiling of DNA G-quadruplex-regulated genes.

DNA G-quadruplex (G4) is a non-canonical four-stranded secondary structure that has been shown to play a role in epigenetic modulation of gene expression. Here, we present a primer on phenotype-specific profiling of DNA G-quadruplex-regulated genes. We provide guidance on in silico exploration of G4-related genes and phenotypes, and in vitro and in vivo validation of the relationship between G4 and phenotype. We describe commonly utilized techniques and detail critical steps involved in determining the phenotype-specific G4-regulated genes for subsequent investigations.

RNA demethylase ALKBH5 promotes colorectal cancer progression by posttranscriptional activation of RAB5A in an m6A-YTHDF2-dependent manner.

BACKGROUND: N6-methyladenosine (m6A) modification is an emerging epigenetic regulatory mechanism in tumourigenesis. Considering that AlkB homolog 5 (ALKBH5) is a well-described m6A demethylase in previous enzyme assays, we aimed to investigate the role of m6A methylation alteration conferred by disturbed ALKBH5 in colorectal cancer (CRC) development. METHODS: Expression of ALKBH5 and its correlation with clinicopathological characteristics of CRC were evaluated using the prospectively maintained institutional database. The molecular role and underlying mechanism of ALKBH5 in CRC were explored using in vitro and in vivo experiments with methylated RNA immunoprecipitation sequencing (MeRIP-seq), RNA-seq, MeRIP-qPCR, RIP-qPCR and luciferase reporter assays. RESULTS: ALKBH5 expression was significantly upregulated in CRC tissues compared to the paired adjacent normal tissues, and higher expression of ALKBH5 was independently associated with worse overall survival in CRC patients. Functionally, ALKBH5 promoted the proliferative, migrative and invasive abilities of CRC cells in vitro and enhanced subcutaneous tumour growth in vivo. Mechanistically, RAB5A was identified as the downstream target of ALKBH5 in CRC development, and ALKBH5 posttranscriptionally activated RAB5A by m6A demethylation, which impeded the YTHDF2-mediated degradation of RAB5A mRNA. In addition, we demonstrated that dysregulation of the ALKBH5-RAB5A axis could affect the tumourigenicity of CRC. CONCLUSIONS: ALKBH5 facilitates the progression of CRC by augmenting the expression of RAB5A via an m6A-YTHDF2-dependent manner. Our findings suggested that ALKBH5-RAB5A axis might serve as valuable biomarkers and effective therapeutic targets for CRC.

Clinical atlas of rectal cancer highlights the barriers and insufficient interventions underlying the unfavorable outcomes in older patients.

Background: Aging confers an increased risk of developing cancer, and the global burden of cancer is cumulating as human longevity increases. Providing adequate care for old patients with rectal cancer is challenging and complex. Method: A total of 428 and 44,788 patients diagnosed with non-metastatic rectal cancer from a referral tertiary care center (SYSU cohort) and the Surveillance Epidemiology and End Results database (SEER cohort) were included. Patients were categorized into old (over 65 years) and young (aged 50-65 years) groups. An age-specific clinical atlas of rectal cancer was generated, including the demographic and clinicopathological features, molecular profiles, treatment strategies, and clinical outcomes. Results: Old and young patients were similar in clinicopathological risk factors and molecular features, including TNM stage, tumor location, tumor differentiation, tumor morphology, lymphovascular invasion, and perineural invasion. However, old patients had significantly worse nutritional status and more comorbidities than young patients. In addition, old age was independently associated with less systemic cancer treatment (adjusted odds ratio 0.294 [95% CI 0.184-0.463, P < 0.001]). We found that old patients had significantly worse overall survival (OS) outcomes in both SYSU (P < 0.001) and SEER (P < 0.001) cohorts. Moreover, the death and recurrence risk of old patients in the subgroup not receiving chemo/radiotherapy (P < 0.001 for OS, and P = 0.046 for time to recurrence [TTR]) reverted into no significant risk in the subgroup receiving chemo/radiotherapy. Conclusions: Although old patients had similar tumor features to young patients, they had unfavorable survival outcomes associated with insufficient cancer care from old age. Specific trials with comprehensive geriatric assessment for old patients are needed to identify the optimal treatment regimens and improve unmet cancer care. Study registration: The study was registered on the research registry with the identifier of researchregistry 7635.

Aberrant methylation in neurofunctional gene serves as a hallmark of tumorigenesis and progression in colorectal cancer.

BACKGROUND: DNA methylation is one of the most promising biomarkers in predicting the prognosis of colorectal cancer (CRC). We aimed to develop a DNA methylation biomarker that could evaluate the prognosis of CRC. METHODS: A promising DNA methylation biomarker was developed by hypermethylated genes in cancer tissue that were identified from Illumina EPIC methylation arrays. A cohort comprising 30 pairs of snap-frozen tumor tissue and adjacent normal tissue was used for correlation analysis between the methylation and expression status of the marker. The other cohort comprising 254 formalin-fixed paraffin-embedded (FFPE) tumor tissue from 254 CRC patients was used for prognosis analysis. RESULTS: Regulating synaptic membrane exocytosis 2 (RIMS2) was hypermethylated and lowly expressed in CRC comparing to adjacent normal tissue. Hypermethylation of RIMS2 in CRC was correlated with less frequent KRAS mutant and high differentiation. RIMS2 promoter methylation showed independent predictive value for survival outcome (P = 0.015, HR 1.992, 95% CI [(1.140-3.48)]), and a combination of RIMS2 methylation with KRAS status could predict prognosis better. CONCLUSIONS: RIMS2 is frequently hypermethylated in CRC, which can silence the expression of RIMS2. RIMS2 methylation is a novel biomarker for predicting the prognosis of CRC.

Fasting-mimicking diet synergizes with ferroptosis against quiescent, chemotherapy-resistant cells.

BACKGROUND: More than ten randomized clinical trials are being tested to evaluate the efficacy, effectiveness and safety of a fasting-mimicking diet (FMD) combined with different antitumor agents. METHODS: UMI-mRNA sequencing, Cell-cycle analysis, Label retention, metabolomics, Multilabeling et al. were used to explore mechanisms. A tandem mRFP-GFP-tagged LC3B, Annexin-V-FITC Apoptosis, TUNEL, H&E, Ki-67 and animal model was used to search for synergistic drugs. FINDINGS: Here we showed that fasting or FMD retards tumor growth more effectively but does not increase 5-fluorouracil/oxaliplatin (5-FU/OXA) sensitivity to apoptosis in vitro and in vivo. Mechanistically, we demonstrated that CRC cells would switch from an active proliferative to a slow-cycling state during fasting. Furthermore, metabolomics shows cell proliferation was decreased to survive nutrient stress in vivo, as evidenced by a low level of adenosine and deoxyadenosine monophosphate. CRC cells would decrease proliferation to achieve increased survival and relapse after chemotherapy. In addition, these fasting-induced quiescent cells were more prone to develop drug-tolerant persister (DTP) tumor cells postulated to be responsible for cancer relapse and metastasis. Then, UMI-mRNA sequencing uncovered the ferroptosis pathway as the pathway most influenced by fasting. Combining fasting with ferroptosis inducer treatment leads to tumor inhibition and eradication of quiescent cells by boosting autophagy. INTERPRETATION: Our results suggest that ferroptosis could improve the antitumor activity of FMD + chemotherapy and highlight a potential therapeutic opportunity to avoid DTP cells-driven tumor relapse and therapy failure. FUNDING: A full list of funding bodies can be found in the Acknowledgements section.

Radiological lymph-node size improves the prognostic value of systemic inflammation index in rectal cancer with pathologically negative nodes.

BACKGROUND: The relationship between the radiological lymph node (rLN) size and survival outcome in node-negative rectal cancer is still uncertain. In this study, we aimed to explore the role of enlarged rLN in predicting the survival of node-negative rectal cancers. METHODS: We retrospectively reviewed the records of 722 node-negative rectal cancer who underwent curative resection. Factors associated with DFS (disease-free survival) and CSS (cancer-specific survival) were assessed with univariate and multivariate analysis. Survival analysis was performed according to presence with or without enlarged rLN. Combining rLN with NLR as a new index-inflammation immune score (IIS) for predicting survival. Comparing different models to assess the predictive powers. RESULTS: A total of 119 patients had tumor recurrence and 73 patients died due to cancer. Patients with enlarged rLN (≥5 mm) was significantly associated with better DFS (HR:0.517, 95%CI:0.339-0.787, p = 0.002) and CSS (HR:0.43, 95%CI:0.242-0.763, p = 0.004). The risk factors of recurrence were rLN, neutrophil-lymphocyte ratio (NLR), CEA level, and distance from the anal verge. The risk of recurrence increased by 1.88- and 2.83-fold for the high score in IIS compared with the low and intermediate score group (All p < 0.001). Similarly, the high score in IIS also increased the risk of cancer-specific death. In the model comparison, the AIC and LR were improved by including the rLN into the NLR model for DFS and CSS prediction (All p < 0.05). CONCLUSIONS: Node-negative rectal cancer patients with enlarged rLN had a better survival outcome. IIS might be a more comprehensive and complete inflammation immune index for survival prediction.

Pan-cancer investigation of C-to-U editing reveals its important role in cancer development and new targets for cancer treatment.

RNA editing is prevalent in the transcriptome and is important for multiple cellular processes. C-to-U RNA editing sites (RES) are relatively rare and understudied in humans, compared to A-to-I editing. However, the functional impact of C-to-U editing in human cancers also remains elusive. Here, we conducted the first comprehensive survey of pan-cancer C-to-U RESs. Surprisingly, we found that the same subset of RESs were associated with multiple features, including patient survival, cancer stemness, tumor mutation burden (TMB), and tumor-infiltrated immune cell compositions (ICC), suggesting an RES-mediated close relationship between these features. For example, editing sites for GALM or IFI6 that led to higher expression were linked to lower survival and more cancer stemness. Also, TMB was found to be lower in prostate cancer cases with ICC-associated RESs in CAVIN1 or VWA8 or higher in prostate cancer cases with thymoma. With experimental support, we also found RESs in CST3, TPI1, or TNC that are linked to immune checkpoint blockade by anti-PD1. We also confirmed through experiments that two C-to-U RESs in CSNK2B or RPS14 had different effects on colon cancer cells. Patients with CSNK2B editing, which increased the expression of the oncogene CLDN18, had a lower response to drugs. On the other hand, drugs worked better on people who had RPS14 editing, which greatly increased ribosome production. In summary, our study demonstrated the important roles of C-to-U RESs across cancers and shed light on personalized cancer therapy.

Accurate tumor segmentation and treatment outcome prediction with DeepTOP.

BACKGROUND: Accurate outcome prediction prior to treatment can facilitate trial design and clinical decision making to achieve better treatment outcome. METHOD: We developed the DeepTOP tool with deep learning approach for region-of-interest segmentation and clinical outcome prediction using magnetic resonance imaging (MRI). DeepTOP was constructed with an automatic pipeline from tumor segmentation to outcome prediction. In DeepTOP, the segmentation model used U-Net with a codec structure, and the prediction model was built with a three-layer convolutional neural network. In addition, the weight distribution algorithm was developed and applied in the prediction model to optimize the performance of DeepTOP. RESULTS: A total of 1889 MRI slices from 99 patients in the phase III multicenter randomized clinical trial (NCT01211210) on neoadjuvant treatment for rectal cancer was used to train and validate DeepTOP. We systematically optimized and validated DeepTOP with multiple devised pipelines in the clinical trial, demonstrating a better performance than other competitive algorithms in accurate tumor segmentation (Dice coefficient: 0.79; IoU: 0.75; slice-specific sensitivity: 0.98) and predicting pathological complete response to chemo/radiotherapy (accuracy: 0.789; specificity: 0.725; and sensitivity: 0.812). DeepTOP is a deep learning tool that could avoid manual labeling and feature extraction and realize automatic tumor segmentation and treatment outcome prediction by using the original MRI images. CONCLUSION: DeepTOP is open to provide a tractable framework for the development of other segmentation and predicting tools in clinical settings. DeepTOP-based tumor assessment can provide a reference for clinical decision making and facilitate imaging marker-driven trial design.

Automatic treatment outcome prediction with DeepInteg based on multimodal radiological images in rectal cancer.

Neoadjuvant systemic treatment before surgery is a prevalent regimen in the patients with advanced-stage or high-risk tumor, which has shaped the treatment strategies and cancer survival in the past decades. However, some patients present with poor response to the neoadjuvant treatment. Therefore, it is of great significance to develop tools to help distinguish the patients that could achieve pathological complete response before surgery to avoid inappropriate treatment. Here, this study demonstrated a multi-task deep learning tool called DeepInteg. In the DeepInteg framework, the segmentation module was constructed based on the CE-Net with a context extractor to achieve end-to-end delineation of region of interest (ROI) from radiological images, then the features of segmented Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) images of each case were fused and input to the classification module based on a convolution neural network for treatment outcome prediction. The dataset with 1700 MRI and CT slices collected from the prospectively randomized clinical trial (NCT01211210) on systemic treatment for rectal cancer was used to develop and systematically optimize DeepInteg. As a result, DeepInteg achieved automatic segmentation of tumoral ROI with Dices of 0.766 and 0.719 and mIoUs of 0.788 and 0.756 in CT and MRI images, respectively. In addition, DeepInteg achieved AUC of 0.833, accuracy of 0.826 and specificity of 0.856 in the prediction for pathological complete response after treatment, which showed better performance compared with the model based on CT or MRI alone. This study provide a robust framework to develop disease-specific tools for automatic delineation of ROI and clinical outcome prediction. The well-trained DeepInteg could be readily applied in clinic to predict pathological complete response after neoadjuvant therapy in rectal cancer patients.

Prevalent Pseudoprogression and Pseudoresidue in Patients With Rectal Cancer Treated With Neoadjuvant Immune Checkpoint Inhibitors.

BACKGROUND: Immune checkpoint inhibitor (ICI) treatment in patients with microsatellite instability-high/mismatch repair deficient (MSI-H/dMMR) tumors holds promise in reshaping organ preservation in rectal cancer. However, the benefits are accompanied by distinctive patterns of response, introducing a dilemma in the response evaluation for clinical decision-making. PATIENTS AND METHODS: Patients with locally advanced rectal cancer with MSI-H/dMMR tumors receiving neoadjuvant ICI (nICI) treatment (n=13) and matched patients receiving neoadjuvant chemoradiotherapy (nCRT; n=13) were included to compare clinical response and histopathologic features. RESULTS: Among the 13 patients receiving nICI treatment, in the final radiologic evaluation prior to surgery (at a median of 103 days after initiation of therapy), progressive disease (n=3), stable disease (n=1), partial response (n=7), and complete response (n=2) were observed. However, these patients were later confirmed as having pathologic complete response, resulting in pseudoprogression and pseudoresidue with incidences of 23.1% (n=3) and 76.9% (n=10), respectively, whereas no pseudoprogression was found in the 13 patients receiving nCRT. We further revealed the histopathologic basis underlying the pseudoprogression and pseudoresidue by discovering the distinctive immune-related regression features after nICI treatment, including fibrogenesis, dense lymphocytes, and plasma cell infiltration. CONCLUSIONS: Pseudoprogression and pseudoresidue were unique and prevalent response patterns in MSI-H/dMMR rectal cancer after nICI treatment. Our findings highlight the importance of developing specific strategies for response evaluation in neoadjuvant immunotherapy to identify patients with a good response in whom sphincter/organ-preserving or watch-and-wait strategies may be considered.

DNA methylation profile in CpG-depleted regions uncovers a high-risk subtype of early-stage colorectal cancer.

BACKGROUND: The current risk stratification system defined by clinicopathological features does not identify the risk of recurrence in early-stage (stage I-II) colorectal cancer (CRC) with sufficient accuracy. We aimed to investigate whether DNA methylation could serve as a novel biomarker for predicting prognosis in early-stage CRC patients. METHODS: We analyzed the genome-wide methylation status of CpG loci using Infinium MethylationEPIC array run on primary tumor tissues and normal mucosa of early-stage CRC patients to identify potential methylation markers for prognosis. The machine-learning approach was applied to construct a DNA methylation-based prognostic classifier for early-stage CRC (MePEC) using the 4 gene methylation markers FAT3, KAZN, TLE4, and DUSP3. The prognostic value of the classifier was evaluated in 2 independent cohorts (n = 438 and 359, respectively). RESULTS: The comprehensive analysis identified an epigenetic subtype with high risk of recurrence based on a group of CpG loci in the CpG-depleted region. In multivariable analysis, the MePEC classifier was independently and statistically significantly associated with time to recurrence in validation cohort 1 (hazard ratio = 2.35, 95% confidence interval = 1.47 to 3.76, P < .001) and cohort 2 (hazard ratio = 3.20, 95% confidence interval = 1.92 to 5.33, P < .001). All results were further confirmed after each cohort was stratified by clinicopathological variables and molecular subtypes. CONCLUSIONS: We demonstrated the prognostic statistical significance of a DNA methylation profile in the CpG-depleted region, which may serve as a valuable source for tumor biomarkers. MePEC could identify an epigenetic subtype with high risk of recurrence and improve the prognostic accuracy of current clinical variables in early-stage CRC.

Clinical spectrum of rectal cancer identifies hallmarks of early-onset patients and next-generation treatment strategies.

BACKGROUND: The incidence of colorectal cancer is increasing among young adults and more rectal cancers are reported. This study aimed to identify the clinical features specific for early-onset rectal cancer and provide insights on cancer management. METHODS: Early-onset (<50 years) and late-onset (≥50 years) rectal cancer patients from a referral tertiary care center (SYSU cohort) and Surveillance Epidemiology and End Results database (SEER cohort) were included to perform a comprehensive comparison on clinical information. RESULTS: A total of 552 and 80,341 patients with stages I-III rectal cancer were included in the SYSU and SEER cohorts, respectively. In the SYSU cohort, early-onset diseases had significantly higher prevalence of family history of cancer and history of HBV infection and lower incidence of comorbidities (p < 0.05). In addition, early-onset patients presented more frequently with advanced node stage (N2 stage: 16.9 vs. 9.3%, p = 0.017) and high-risk features, including mucinous or signet cell carcinomas (21.8 vs. 12.9%, p = 0.014), poorly differentiated tumors (28.8 vs. 15.4%, p = 0.002), and perineural invasion (14.5 vs. 7.9%, p = 0.027) compared with late-onset patients. However, early-onset patients received more neoadjuvant (18.5 vs. 11.2%, p = 0.032) and adjuvant treatments (71.0 vs. 45.8%, p < 0.001), and they had better overall survival in both SYSU (HR 0.57, 95% CI: 0.34-0.95; p = 0.029) and SEER (HR 0.38, 95% CI: 0.37-0.40; p < 0.001) cohorts. CONCLUSION: Early-onset rectal cancers are distinct from late-onset cases in clinicopathological features, treatment modalities, and outcomes. The clinical trials and studies that are specific for young populations are needed to develop optimal strategies for cancer screening, treatment, and surveillance.

Genomic G-quadruplex folding triggers a cytokine-mediated inflammatory feedback loop to aggravate inflammatory diseases.

DNA G-quadruplex is a non-canonical secondary structure that could epigenetically regulate gene expression. To investigate the regulating role of G-quadruplex, we devised an integrating method to perform the algorithm profiling and genome-wide analysis for the dynamic change of genomic G-quadruplex and RNA profiles in rat nucleus pulposus cells by inducing G-quadruplex folding with multiple stabilizers. A group of genes potentially regulated by G-quadruplex and involved in the inflammation process has been identified. We found that G-quadruplex folding triggers inflammation response by upregulating inflammatory cytokines, which could promote G-quadruplex folding in a manner of positive feedback loop. Moreover, we confirmed that G-quadruplex is a marker indicating elevated inflammatory status and G-quadruplex folding facilitates the development of inflammatory diseases using in vivo intervertebral disc degeneration models. The crosstalk between G-quadruplex and inflammatory cytokines plays a vital role in regulating inflammation-derived diseases, which may provide new insights into the blocking target.

Accelerated biological aging in COVID-19 patients.

Chronological age is a risk factor for SARS-CoV-2 infection and severe COVID-19. Previous findings indicate that epigenetic age could be altered in viral infection. However, the epigenetic aging in COVID-19 has not been well studied. In this study, DNA methylation of the blood samples from 232 healthy individuals and 413 COVID-19 patients is profiled using EPIC methylation array. Epigenetic ages of each individual are determined by applying epigenetic clocks and telomere length estimator to the methylation profile of the individual. Epigenetic age acceleration is calculated and compared between groups. We observe strong correlations between the epigenetic clocks and individual's chronological age (r > 0.8, p < 0.0001). We also find the increasing acceleration of epigenetic aging and telomere attrition in the sequential blood samples from healthy individuals and infected patients developing non-severe and severe COVID-19. In addition, the longitudinal DNA methylation profiling analysis find that the accumulation of epigenetic aging from COVID-19 syndrome could be partly reversed at late clinic phases in some patients. In conclusion, accelerated epigenetic aging is associated with the risk of SARS-CoV-2 infection and developing severe COVID-19. In addition, the accumulation of epigenetic aging from COVID-19 may contribute to the post-COVID-19 syndrome among survivors.

Current Surveillance After Treatment is Not Sufficient for Patients With Rectal Cancer With Negative Baseline CEA.

BACKGROUND: Serum CEA has been widely used to screen for potential recurrent disease after resection in rectal cancer. However, the influence of baseline CEA on the performance of CEA in recurrence surveillance needs to be investigated. PATIENTS AND METHODS: This longitudinal cohort study included 484 patients with nonmetastatic rectal cancer from 18,013 patients in a prospectively enrolled institutional database program of colorectal disease. Baseline CEA levels were determined before treatment, and CEA-based follow-up tests and examinations were applied in the surveillance after treatment. RESULTS: A total of 62.6% (62/99) overall, 53.5% (23/43) local, and 64.9% (50/77) distant recurrences were seen in patients who had similar CEA levels with their baseline statuses. The sensitivity of elevated CEA levels during surveillance for overall recurrence was significantly lower in patients with negative baseline CEA than in those with elevated baseline CEA levels (41.3% vs 69.4%; P =.007). Moreover, similar results were observed in the surveillance for local (50% vs 61.5%; P =.048) and distant (39.6% vs 72.4%; P =.005) recurrences between these 2 patient groups. However, CEA had comparable and excellent specificity during surveillance for recurrent disease in these groups. The addition of CA19-9 to the CEA assay significantly improved the sensitivity in recurrence surveillance for patients with negative baseline CEA (49.2% vs 41.3%; P =.037). Finally, we identified a subgroup of CEA-turn recurrences characterized by negative CEA at baseline, elevated CEA at recurrence, and worse survival outcomes after recurrence (hazard ratio, 1.88; 95% CI, 1.07-3.30; P =.026). CONCLUSIONS: In patients with rectal cancer with negative baseline CEA, serum CEA had insufficient sensitivity in recurrence surveillance after treatment, and additional surveillance may improve oncologic outcomes. Baseline CEA should be considered before CEA-based surveillance can be applied in the follow-up trials.

Systemic Inflammation Status Relates to Anti-inflammatory Drug Benefit and Survival in Rectal Cancer.

BACKGROUND: Systemic inflammation status has been recognized as a sensitive marker associated with survival in cancers and anti-inflammatory treatment outcomes in inflammation-derived diseases. This study aimed to investigate the role of systemic inflammation status as a predictive marker for survival and anti-inflammatory treatment benefit in rectal cancer patients. METHODS: A total of 475 patients with stage I-III rectal cancer receiving curative resection were prospectively enrolled. The platelet-neutrophils to lymphocytes ratio (PNLR) that integrates neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios was applied to enable a comprehensive evaluation of systemic inflammation status and investigate its association with survival and nonsteroidal anti-inflammatory drugs (NSAIDs) benefit. Patients were grouped according to baseline PNLR and perioperative use of NSAIDs. RESULTS: The high-PNLR group had worse 5-y disease-free survival (DFS) compared with the low-PNLR group (61.2% versus 70.9%, P = 0.014). Multivariate analyses confirmed that PNLR was an independent predictor for DFS (hazard ratio [HR] 1.42, 95% CI: 1.03-1.97, P = 0.031). A nomogram including PNLR and other independent prognostic factors was developed and validated to predict DFS. In the high-PNLR subset, NSAIDs group had a 21.3% lower risk of recurrence than non-NSAIDs group (P = 0.009), and multivariate analysis confirmed the independently significant association of perioperative NSAIDs use with better DFS (hazard ratio 0.36, 95% CI 0.16-0.78, P = 0.010). However, this association was not significant in the low-PLR subset. CONCLUSIONS: Baseline PNLR could be used to predict DFS and NSAIDs benefit in rectal cancer patients. This study highlights the potential survival benefit from the anti-inflammatory treatment in the patients with elevated systemic inflammation status in cancer patients.

Silence of a dependence receptor CSF1R in colorectal cancer cells activates tumor-associated macrophages.

BACKGROUND: Colony-stimulating factor 1 receptor (CSF1R), a classic tyrosine kinase receptor, has been identified as a proto-oncogene in multiple cancers. The CSF1/CSF1R axis is essential for the survival and differentiation of M2-phenotype tumor-associated macrophages (M2 TAMs). However, we found here that the CSF1R expression was abnormally down-regulated in colorectal cancer (CRC), and its biological functions and underlying mechanisms have become elusive in CRC progression. METHODS: The expression of class III receptor tyrosine kinases in CRC and normal intestinal mucosa was accessed using The Cancer Genome Atlas and Gene Expression Omnibus datasets and was further validated by our tested cohort. CSF1R was reconstructed in CRC cells to identify its biological functions in vitro and in vivo. We compared CSF1R expression and methylation differences between CRC cells and macrophages. Furthermore, a co-culture system was used to mimic a competitive mechanism between CSF1R-overexpressed CRC cells and M2-like macrophages. We utilized a CSF1R inhibitor PLX3397 to ablate M2 TAMs and evaluated its efficacy on CRC treatment in animal models. RESULTS: We found here that the CSF1R is silenced in CRC, and the reintroduced expression of the receptor in CRC cells can be cleaved by caspases and constrain tumor growth in vitro and in vivo, functioning as a tumor suppressor gene. We further identified CSF1R as a novel dependence receptor, which has the potential to act as either a tumor suppressor gene or an oncogene, depending on its activated state. In CRC tumors, CSF1R expression is enriched in TAMs, and its expression is associated with poor prognosis in patients ith CRC. In a co-culture system, CRC cells expressing CSF1R compete with M2-like macrophages for CSF1R ligands, resulting in a decrease in CSF1R activation and cell proliferation in macrophages. Blocking CSF1R by PLX3397 could deplete M2 TAMs and augments CD8+ T cell infiltration, effectively inhibiting tumor growth and metastasis and improving responses to chemotherapy and immunotherapy. CONCLUSION: Our findings revealed that CSF1R is a novel identified dependence receptor silenced in CRC. The silence abalienates its ligands to stimulate CSF1R expressed on M2 TAMs, which is an appealing therapeutic target for M2 TAM depletion and CRC treatment.