Tumor-infiltrating PD-1+ immune cell density is associated with response to neoadjuvant chemoradiotherapy in rectal cancer

A machine learning approach to risk-stratification of gastric cancer based on tumour-infiltrating immune cell profiles

BACKGROUND

Gastric cancer (GC) is a highly heterogeneous disease, and the response of patients to clinical treatment varies substantially. There is no satisfactory strategy for predicting curative effects to date. We aimed to explore a new method for predicting the clinical efficacy of GC treatment based on immune variables detected via flow cytometry.

METHODS

We collected 394 tumour tissues from GC patients for flow cytometry analysis and gating analysis of tumour-infiltrating immune cells (TIICs). Unsupervised consensus clusters were generated from the cohort to classify patients into different phenogroups, and their clinical characteristics were examined. The derived model was evaluated via principal component analysis and t-distributed stochastic neighbourhood embedding analysis. Kaplan-Meier's curves were used to determine the prognosis during a 920-day-long median follow-up period (interquartile range: 834-1071 days). Adjusted multivariate Cox regression analysis was used to evaluate the association of clusters with disease-free survival (DFS) and recurrence.

RESULTS

All patients were classified based on their TIIC profiles into the C1 (characterized by low CD45 negative cell, high lymphocyte, high neutrophil and low CD3 + T cell levels), C2 (characterized by high CD8 + CD279+ cell and low CD4+ Th and CD8+ Tc cell numbers) and C3 (characterized by high CD4 + CD25+ and Treg cell levels) phenogroups. Patients from the three clusters had varied pathologies, MMR statuses and TIIC distribution patterns (p < .05). Kaplan-Meier's analysis showed that the prognosis of C3 was inferior compared to C1 and C2 (p = .0025). Adjusted Cox proportional hazard models helped us identify that C1 and C2 exhibited a favourable factor of recurrence after surgery, compared to C3. Kaplan-Meier's analysis showed that C1 and C2 were associated with a better DFS than C3 in some GC patient subgroups.

CONCLUSIONS

The machine learning model developed was found to be effective model at predicting the prognosis of patients with GC and their TIIC profiles for risk stratification in clinical settings.

Prognostic value of CD163+ macrophages in solid tumor malignancies: A scoping review

Tumor-associated macrophages (TAMs) play crucial roles in development and progression of malignant diseases. Notably, CD163+ TAMs likely perform specific pro-tumorigenic functions, suggesting that this subset may serve as both prognostic biomarkers and targets for future anti-cancer therapy. We conducted a scoping review to map the current knowledge on the prognostic role of CD163+ TAMs in the five most lethal cancers worldwide: Lung, colorectal, gastric, liver, and breast cancer. For all cancer types, most studies showed that high tumoral presence of CD163+ cells was associated with poor patient outcome, and this association was more frequently observed when CD163+ cells were measured at the tumor periphery compared to more central parts of the tumor. These results support that CD163+ TAMs represent a biomarker of poor patient outcome across a variety of solid tumors, and highlight the relevance of further investigations of CD163+ TAMs as targets of future immunotherapies.

Tumour-infiltrating Lymphocytes and Radiation Therapy in Rectal Cancer: Systematic Review and Meta-analysis

AIM

Tumour-infiltrating lymphocytes (TILs) represent a promising cancer biomarker. Different TILs, including CD8+, CD4+, CD3+, and FOXP3+, have been associated with clinical outcomes. However, data are lacking regarding the value of TILs for patients receiving radiation therapy (RT). We conducted a systemic review and meta-analysis of available data evaluating TILs for patients receiving curative-intent therapy including RT.

MATERIALS AND METHODS

Eligible studies presented a defined cohort of patients who all received curative-intent therapy, including RT, and also reported the relationship between any TIL score and either tumour response or survival outcomes. After comprehensive search of online databases (PubMed, EMBASE, Cochrane, and Web of Science), 2 authors conducted title, abstract, and whole-text review for quality and risk of bias following Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Data from publications that met quality criteria were grouped via (1) TIL analysed, (2) pre- or post-RT TIL assessment, and (3) clinical outcome measured.

RESULTS

Initial search yielded 669 unique studies. Thirty-one studies met quality criteria, of which 20 studied rectal cancer (RC), 4 oesophageal, 3 pancreas, 2 lung, cervical/uterine 1 each. We conducted systematic review and meta-analysis of the RC publications. All except 2 were single-institutional cohort studies. After meta-analysis, the pre-RT epithelial CD8+ (p = 0.04) and stromal FOXP3+ (p = 0.01) counts were associated with survival without disease, while pre-RT epithelial (p = 0.02) and stromal (p = 0.001) FOXP3+ TILs were associated with overall survival. On post-RT analysis, epithelial (p = .04) and stromal (p = 0.02) CD8+ TILs were associated with survival without disease and epithelial CD8+ TILs were associated with overall survival (p = 0.01).Preoperative CD8+ and FOXP3+ TILs were generally associated with tumour response to RT, but meta-analysis was not conducted due to heterogeneity of response measurement techniques.

CONCLUSION

TILs represent a useful parameter for tumour response and survival outcomes for patients receiving curative-intent therapy, including RT for RC. Future work should aim to standardise TIL measurement and quantification methods and to develop protocols to clarify clinical application of these findings.

Prognostic Significance of Desmoplastic Reaction After Neoadjuvant Chemoradiotherapy in Advanced Rectal Cancer

BACKGROUND

Desmoplastic reaction is recognized as a prognostic factor in colorectal cancer. However, its significance in locally advanced rectal cancer after neoadjuvant chemoradiotherapy remains underexplored.

OBJECTIVE

To assess the prognostic value of desmoplastic reaction in specimens from patients with advanced rectal cancer after chemoradiotherapy.

DESIGN

This was a retrospective study.

SETTINGS

This study was conducted at a single comprehensive cancer center.

PATIENTS

The study included 255 patients with advanced rectal cancer who underwent fluoropyrimidine-based chemoradiotherapy followed by total mesorectal excision from 2005 to 2014. Desmoplastic reaction was classified into mature, intermediate, and immature categories based on histological analysis.

MAIN OUTCOME MEASURES

The primary outcomes were recurrence-free survival and overall survival.

RESULTS

Desmoplastic reaction was classified as mature (69.0%), intermediate (5.5%), or immature (25.5%). The mature group had a higher percentage of good responders (34.1%) compared with the intermediate (0%) and immature (4.6%) groups ( p < 0.0001). The mature group correlated with better outcomes, with a higher 5-year recurrence-free survival (85.4%) and overall survival (93.0%) as compared with intermediate (45.1% and 76.2%, respectively) and immature (65.8% and 88.8%, respectively) groups. In the multivariable analysis, intermediate/immature desmoplastic reaction was significantly associated with poorer recurrence-free survival ( p = 0.03). Among poor responders, intermediate/immature desmoplastic reaction was associated with poorer recurrence-free survival ( p = 0.03). Adjuvant chemotherapy did not significantly improve the 5-year recurrence-free survival rate for the mature group (adjuvant chemotherapy vs no chemotherapy, 86.4% vs 84.8%; p = 0.64), with worse trends observed in the intermediate/immature combined group (55.9% vs 69.4%, respectively, p = 0.27).

LIMITATIONS

The limitations include the subjective nature of the desmoplastic reaction assessment and the retrospective design of the study.

CONCLUSIONS

Desmoplastic reaction in surgical specimens after chemoradiotherapy is associated with responses to chemoradiotherapy and serves as a significant prognostic factor in advanced rectal cancer, particularly for those responding poorly to chemoradiotherapy. See Video Abstract .

IMPORTANCIA PRONSTICA DE LA REACCIN DESMOPLSICA TRAS LA QUIMIORRADIOTERAPIA NEOADYUVANTE EN EL CNCER RECTAL AVANZADO

ANTECEDENTES:La reacción desmoplásica se reconoce como un factor pronóstico en el cáncer colorrectal. Sin embargo, su importancia en el cáncer rectal localmente avanzado después de la quimiorradioterapia neoadyuvante sigue sin explorarse.OBJETIVO:Evaluar el valor pronóstico de la reacción desmoplásica en muestras de pacientes con cáncer rectal avanzado después de la quimiorradioterapia.DISEÑO:Este es un estudio retrospectivo.ESCENARIO:Este estudio se llevó a cabo en un solo centro oncológico integral.PACIENTES:El estudio incluyó a 255 pacientes con cáncer rectal avanzado que se sometieron a quimiorradioterapia basada en fluoropirimidina seguida de una escisión mesorrectal total entre 2005 y 2014. La reacción desmoplásica se clasificó en categorías madura, intermedia e inmadura según el análisis histológico.RESULTADOS PRINCIPALES:Los resultados primarios fueron la supervivencia sin recurrencia y la supervivencia general. RESULTADOS: La reacción desmoplásica se clasificó como madura (69,0%), intermedia (5,5%) o inmadura (25,5%). El grupo maduro tuvo un mayor porcentaje de buenos respondedores (34,1%) en comparación con los grupos intermedio (0%) e inmaduro (4,6%) (p < 0,0001). El grupo maduro se correlacionó con mejores resultados, con una mayor supervivencia libre de recurrencia a 5 años (85,4%) y supervivencia general (93,0%) en comparación con los grupos intermedio (45,1% y 76,2%, respectivamente) e inmaduro (65,8% y 88,8%, respectivamente). En el análisis multivariable, la reacción desmoplásica intermedia/inmadura se asoció significativamente con una peor supervivencia libre de recurrencia ( p = 0,03). Entre los malos respondedores, la reacción desmoplásica intermedia/inmadura se asoció con una peor supervivencia libre de recurrencia (p = 0,03). La quimioterapia adyuvante no mejoró significativamente la tasa de supervivencia sin recurrencia a 5 años para el grupo maduro (quimioterapia adyuvante vs. ninguna quimioterapia, 86,4% vs. 84,8%; p = 0,64), observándose tendencias peores en el grupo combinado intermedio/inmaduro (55,9% vs. 69,4%, respectivamente, p = 0,27).LIMITACIONES:Las limitaciones incluyen la naturaleza subjetiva de la evaluación de la reacción desmoplásica y el diseño retrospectivo del estudio.CONCLUSIONES:La reacción desmoplásica en muestras quirúrgicas después de la quimiorradioterapia se asocia con respuestas a la quimiorradioterapia y sirve como un factor pronóstico significativo en el cáncer rectal avanzado, particularmente para aquellos que responden mal a la quimiorradioterapia. (Traducción-Yesenia Rojas-Khalil ).

Are the tumor microenvironment characteristics of pretreatment biopsy specimens of colorectal cancer really effectively predict the efficacy of neoadjuvant therapy: A retrospective multicenter study

More and more studies had pointed out that the tumor microenvironment characteristics based on colorectal cancer (CRC) pretreatment biopsy specimens could effectively predict the efficacy of neoadjuvant therapy, but under hematoxylin and eosin (HE) staining, whether the tumor microenvironment characteristics observed by pathologists could predict the efficacy of neoadjuvant therapy remains to be discussed. We collected 106 CRC patients who received neoadjuvant treatment and surgical resection from 3 hospitals. The number of mitosis, inflammation degree, desmoplastic reaction (DR), necrosis, tumor-stroma ratio (TSR) and tumor budding (TB) of CRC pretreatment biopsy specimens were observed under HE staining, and the degree of tumor pathological remission of CRC surgical specimens after neoadjuvant treatment was evaluated. According to the tumor regression grade (TRG), patients were divided into good-responders (TRG 0-1) and non-responders (TRG 2-3). All data were analyzed with SPSS software (version 23.0) to evaluate the correlation between the number of mitosis, inflammation degree, DR, necrosis, TSR and TB in pretreatment biopsy samples and the treatment effect. In univariate analysis, mitosis (P = .442), inflammation degree (P = .951), DR (P = .186), necrosis (P = .306), TSR (P = .672), and TB (P = .327) were not associated with the response to neoadjuvant therapy. However, we found that for colon cancer, rectal cancer was more likely to benefit from neoadjuvant therapy (P = .024). In addition, we further analyzed the impact of mitosis, inflammation degree, DR, necrosis, TSR and TB on neoadjuvant therapy in rectal cancer, and found that there was no predictive effect. By analyzing the characteristics of tumor microenvironment of CRC pretreatment biopsy specimens under HE staining, such as mitosis, inflammation degree, DR, necrosis, TSR and TB, it was impossible to effectively predict the efficacy of neoadjuvant therapy for CRC.

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.

Intratumoral Budding and CD8-Positive T-cell Density in Pretreatment Biopsies as a Predictor of Response to Neoadjuvant Chemoradiotherapy in Advanced Rectal Cancer

BACKGROUND

Neoadjuvant chemoradiotherapy (CRT) is the standard treatment for advanced rectal cancer. Yet, the response to CRT varies from complete response to zero tumor regression.

MATERIALS AND METHODS

The impact of intratumoral budding (ITB) and intratumoral CD8+ cell density on response to CRT and survival were evaluated in biopsy samples from 266 patients with advanced rectal cancer who were treated with long-course neoadjuvant CRT. The expression of epithelial-mesenchymal transition (EMT) markers was compared between patients with high and low ITB, using data from 174 patients with RNA sequencing.

RESULTS

High ITB was observed in 62 patients (23.3%). There was no association between ITB and CD8+ cell density. The multivariable logistic regression analysis showed that high CD8+ cell density (OR, 2.69; 95% CI, 1.45-4.98; P = .002) was associated with good response to CRT, whereas high ITB (OR, 0.33; 95% CI, 0.14-0.80; P = .014) was associated with poor response. Multivariable Cox regression analysis for survival showed that high CD8+ cell density was associated with better recurrence-free survival (HR, 0.41; 95% CI, 0.24-0.72; P = .002) and overall survival (HR, 0.36; 95% CI, 0.17-0.74; P = .005), but significance values for ITB were marginal (P = .104 for recurrence-free survival and P = .163 for overall survival). The expression of EMT-related genes was not significantly different between patients with high and low ITB.

CONCLUSION

ITB and CD8+ cell density in biopsy samples may serve as useful biomarkers to predict therapy response in patients with rectal cancer treated with neoadjuvant CRT.

Implications of Rectal Cancer Radiotherapy on the Immune Microenvironment: Allies and Foes to Therapy Resistance and Patients' Outcome

Aside from surgical resection, locally advanced rectal cancer is regularly treated with neoadjuvant chemoradiotherapy. Since the concept of cancer treatment has shifted from only focusing on tumor cells as drivers of disease progression towards a broader understanding including the dynamic tumor microenvironment (TME), the impact of radiotherapy on the TME and specifically the tumor immune microenvironment (TIME) is increasingly recognized. Both promoting as well as suppressing effects on anti-tumor immunity have been reported in response to rectal cancer (chemo-)radiotherapy and various targets for combination therapies are under investigation. A literature review was conducted searching the PubMed database for evidence regarding the pleiotropic effects of (chemo-)radiotherapy on the rectal cancer TIME, including alterations in cytokine levels, immune cell populations and activity as well as changes in immune checkpoint proteins. Radiotherapy can induce immune-stimulating and -suppressive alterations, potentially mediating radioresistance. The response is influenced by treatment modalities, including the dosage administered and the highly individual intrinsic pre-treatment immune status. Directly addressing the main immune cells of the TME, this review aims to highlight therapeutical implications since efficient rectal cancer treatment relies on personalized strategies combining conventional therapies with immune-modulating approaches, such as immune checkpoint inhibitors.

CD11c+ and IRF8+ cell densities in rectal cancer biopsies predict outcomes of neoadjuvant chemoradiotherapy

Approximately 20% of locally advanced rectal cancer (LARC) patients treated preoperatively with chemoradiotherapy (CRT) achieve pathologically confirmed complete regression. However, there are no clinically implemented biomarkers measurable in biopsies that are predictive of tumor regression. Here, we conducted multiplexed immunophenotyping of rectal cancer diagnostic biopsies from 16 LARC patients treated preoperatively with CRT. We identified that patients with greater tumor regression had higher tumor infiltration of pan-T cells and IRF8+HLA-DR+ cells prior to CRT. High IRF8+HLA-DR+ cell density was further associated with prolonged disease-specific survival with 83% survival at 5 y compared to 28% in patients with low infiltration. Contrastingly, low CD11c+ myeloid cell infiltration prior to CRT was a putative biomarker associated with longer 3- and 5-y disease-free survival. The results demonstrate the potential use of rectal cancer diagnostic biopsies to measure IRF8+ HLA-DR+ cells as predictors of CRT-induced tumor regression and CD11c+ myeloid cells as predictors of LARC patient survival.

Immune Response and Immune Checkpoint Molecules in Patients with Rectal Cancer Undergoing Neoadjuvant Chemoradiotherapy: A Review

It is well-established that tumor antigens and molecules expressed and secreted by cancer cells trigger innate and adaptive immune responses. These two types of anti-tumor immunity lead to the infiltration of the tumor's microenvironment by immune cells with either regulatory or cytotoxic properties. Whether this response is associated with tumor eradication after radiotherapy and chemotherapy or regrowth has been a matter of extensive research through the years, mainly focusing on tumor-infiltrating lymphocytes and monocytes and their subtypes, and the expression of immune checkpoint and other immune-related molecules by both immune and cancer cells in the tumor microenvironment. A literature search has been conducted on studies dealing with the immune response in patients with rectal cancer treated with neoadjuvant radiotherapy or chemoradiotherapy, assessing its impact on locoregional control and survival and underlying the potential role of immunotherapy in the treatment of this cancer subtype. Here, we provide an overview of the interactions between local/systemic anti-tumor immunity, cancer-related immune checkpoint, and other immunological pathways and radiotherapy, and how these affect the prognosis of rectal cancer patients. Chemoradiotherapy induces critical immunological changes in the tumor microenvironment and cancer cells that can be exploited for therapeutic interventions in rectal cancer.

Transcriptomic Analyses of Pretreatment Tumor Biopsy Samples, Response to Neoadjuvant Chemoradiotherapy, and Survival in Patients With Advanced Rectal Cancer

Importance

Neoadjuvant chemoradiotherapy (CRT) is the standard of care for advanced rectal cancer. Yet, estimating response to CRT remains an unmet clinical challenge.

Objective

To investigate and better understand the transcriptomic factors associated with response to neoadjuvant CRT and survival in patients with advanced rectal cancer.

Design, Setting, and Participants

A single-center, retrospective, case series was conducted at a comprehensive cancer center. Pretreatment biopsies from 298 patients with rectal cancer who were later treated with neoadjuvant CRT between April 1, 2004, and September 30, 2020, were analyzed by RNA sequencing. Data analysis was performed from July 1, 2021, to May 31, 2022.

Exposures

Chemoradiotherapy followed by total mesorectal excision or watch-and-wait management.

Main Outcomes and Measures

Transcriptional subtyping was performed by consensus molecular subtype (CMS) classification. Immune cell infiltration was assessed using microenvironment cell populations-counter (MCP-counter) scores and single-sample gene set enrichment analysis (ssGSEA). Patients with surgical specimens of tumor regression grade 3 to 4 or whose care was managed by the watch-and-wait approach for more than 3 years were defined as good responders.

Results

Of the 298 patients in the study, 205 patients (68.8%) were men, and the median age was 61 (IQR, 52-67) years. Patients classified as CMS1 (6.4%) had a significantly higher rate of good response, albeit survival was comparable among the 4 subtypes. Good responders exhibited an enrichment in various immune-related pathways, as determined by ssGSEA. Microenvironment cell populations-counter scores for cytotoxic lymphocytes were significantly higher for good responders than nonresponders (median, 0.76 [IQR, 0.53-1.01] vs 0.58 [IQR, 0.43-0.83]; P < .001). Cytotoxic lymphocyte MCP-counter score was independently associated with response to CRT, as determined in the multivariable analysis (odds ratio, 3.81; 95% CI, 1.82-7.97; P < .001). Multivariable Cox proportional hazards regression analysis, including postoperative pathologic factors, revealed the cytotoxic lymphocyte MCP-counter score to be independently associated with recurrence-free survival (hazard ratio [HR], 0.38; 95% CI, 0.16-0.92; P = .03) and overall survival (HR, 0.16; 95% CI, 0.03-0.83; P = .03).

Conclusions and Relevance

In this case series of patients with rectal cancer treated with neoadjuvant CRT, the cytotoxic lymphocyte score in pretreatment biopsy samples, as computed by RNA sequencing, was associated with response to CRT and survival. This finding suggests that the cytotoxic lymphocyte score might serve as a biomarker in personalized multimodal rectal cancer treatment.

Tim3 and PD-1 as a therapeutic and prognostic targets in colorectal cancer: Relationship with sidedness, clinicopathological parameters, and survival

Background

Colorectal cancer (CRC) is a heterogeneous disease that complicates predicting patients' prognosis and their response to treatment. CRC prognosis is influenced by the tumor microenvironment (TME). The immune system is a critical component of the TME. Programmed cell death receptor 1 (PD-1) and T-cell immunoglobulin and mucin-domain containing-3 (Tim3) are inhibitory immune checkpoints that regulate immune response and may provide prognostic power. However, the effect of their expressions and co-expressions on the CRC prognosis remains unclear. Accordingly, this study aimed to investigate the prognostic value of the CD8, CD3, PD-1, Tim3 expression, and PD-1/Tim3 co-expression in patients with CRC.

Materials and Methods

One hundred and thirty six patients with CRC who underwent curative surgery were enrolled in the study. Immunohistochemical staining was performed for PD-1, Tim3, CD8, and CD3, and the expression of each marker was evaluated in the center of the tumor (CT), invasive margin (IM), and adjacent normal-like tissue.

Result

Our results indicated that high expression of PD-1 in IM was significantly associated with lower TNM stage, T-stage, M-stage, lack of metastasis, the presence of tertiary lymphoid structure (TLS), lack of recurrence (in the left-sided tumors), and larger tumor size (in right-sided tumors) (P<0.05). High expression of PD-1 in IM was also associated with improved overall survival (OS) in a subgroup of patients with high CD8 expression. High Tim3 expression in CT was associated with higher M-stage (M1) (in left-sided CRCs) (P<0.05). It was also associated with decreased OS in total cohort and left-sided CRCs and represented an independent prognostic factor for CRC patients in multivariate analysis. PD-1 and Tim3 co-expression had no synergistic effects on predicting OS.

Conclusion

Our findings suggest that the clinicopathological and prognostic significance of immune system-related markers such as CD8, PD-1, and Tim3 depends on the primary tumor sides. We also showed that Tim3 could act as a prognostic factor and therapeutic target in CRC. This marker is probably a more preferred target for immunotherapy than PD-1, especially in left-sided CRCs.

Chemotherapy to potentiate the radiation-induced immune response

Chemoradiation (CRT) is a conventional therapy used in local cancers, especially when they are locally advanced. Studies have shown that CRT induces strong anti-tumor responses involving several immune effects in pre-clinical models and humans. In this review, we have described the various immune effects involved in CRT efficacy. Indeed, effects such as immunological cell death, activation and maturation of antigen-presenting cells, and activation of an adaptive anti-tumor immune response are attributed to CRT. As often described in other therapies, various immunosuppressive mechanisms mediated, in particular, by Treg and myeloid populations may reduce the CRT efficacy. We have therefore discussed the relevance of combining CRT with other therapies to potentiate the CRT-induced anti-tumor effects.

Landscape of prognosis and immunotherapy responsiveness under tumor glycosylation-related lncRNA patterns in breast cancer

Aberrant glycosylation, a post-translational modification of proteins, is regarded to engage in tumorigenesis and malignant progression of breast cancer (BC). The altered expression of glycosyltransferases causes abnormal glycan biosynthesis changes, which can serve as diagnostic hallmarks in BC. This study attempts to establish a predictive signature based on glycosyltransferase-related lncRNAs (GT-lncRNAs) in BC prognosis and response to immune checkpoint inhibitors (ICIs) treatment. We firstly screened out characterized glycosyltransferase-related genes (GTGs) through NMF and WGCNA analysis and identified GT-lncRNAs through co-expression analysis. By using the coefficients of 8 GT-lncRNAs, a risk score was calculated and its median value divided BC patients into high- and low-risk groups. The analyses unraveled that patients in the high-risk group had shorter survival and the risk score was an independent predictor of BC prognosis. Besides, the predictive efficacy of our risk score was higher than other published models. Moreover, ESTIMATE analysis, immunophenoscore (IPS), and SubMAP analysis showed that the risk score could stratify patients with distinct immune infiltration, and patients in the high-risk group might benefit more from ICIs treatment. Finally, the vitro assay showed that MIR4435-2HG might promote the proliferation and migration of BC cells, facilitate the polarization of M1 into M2 macrophages, enhance the migration of macrophages and increase the PD-1/PD-L1/CTLA4 expression. Collectively, our well-constructed prognostic signature with GT-lncRNAs had the ability to identify two subtypes with different survival state and responses to immune therapy, which will provide reliable tools for predicting BC outcomes and making rational follow-up strategies.