Lymphocyte recovery from radiation-induced lymphopenia in locally advanced esophageal squamous cell carcinoma: correlations with prognosis and lymphocyte-related organs.

BACKGROUND: Limited studies explored the relationship between lymphocyte recovery after definitive concurrent chemoradiotherapy (dCCRT) and prognosis in esophageal squamous cell carcinoma (ESCC). METHODS: ESCC patients with obtainable absolute lymphocyte counts (ALCs) at 6 months after dCCRT were screened from prospective trials. Patients were divided into groups according to the grade of ALC nadir during radiotherapy (G4 or G1-3) and lymphocyte recovery status, which was assessed by lymphocyte recovery index (LRI), calculated as the ratio of post- to pre-treatment lymphocyte counts. Cox analysis was conducted to evaluate the prognostic significance of lymphocyte recovery status. Irradiated relative volumes of the bone marrow (BM) and spleen and effective dose to immune cells (EDIC) were collected to identify their impacts on lymphocyte recovery status by logistic analysis. RESULTS: 232 patients were enrolled. In 69 patients with G4 ALC nadir (group A and B) and 163 patients with G1-3 ALC nadir (group C and D) during dCCRT, 27 (group A) and 67 (group C) patients showed an insufficient level of lymphocyte recovery (LRI < 60%), and 42 (group B) and 96 (group D) patients showed a satisfactory level of lymphocyte recovery (LRI ≥ 60%). Cox multivariable analysis revealed that inadequate lymphocyte recovery was significantly associated with worse overall survival (HR, 2.80 and 1.70) and local recurrence-free survival (HR, 2.82 and 1.60) both in group A vs group B and group C vs group D. Logistic analysis identified BM V5 (OR 4.24 and 2.29) as an independent predictor of inadequate lymphocyte recovery from G4 or G1-3 ALC nadir, respectively. CONCLUSIONS: Insufficient lymphocyte recovery might serve as a valuable prognostic factor, regardless of whether patients experienced G4 or G1-3 ALC nadir during radiotherapy. Additionally, it was observed that a larger relative volume of BM receiving ≥ 5 Gy was correlated with a higher risk of insufficient lymphocyte recovery.

Less Irradiation to Lymphocyte-Related Organs Reduced the Risk of G4 Lymphopenia in Esophageal Cancer: Re-Analysis of Prospective Trials.

BACKGROUND: This study aimed to explore the relationship between irradiation of lymphocyte-related organs at risk (LOARs) and lymphopenia during definitive concurrent chemoradiotherapy (dCCRT) for esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: Cases of ESCC patients who received dCCRT from 2 prospective clinical trials were identified. To find its correlation with survival outcomes, grades of absolute lymphocyte counts (ALCs) nadir during radiotherapy were recorded following COX analysis. Associations of lymphocytes at nadir and dosimetric parameters including relative volumes of spleen and bone marrow receiving 0.5, 1, 2, 3, 5, 10, 20, 30, and 50Gy (V0.5, V1, V2, V3, V5, V10, V20, V30, and V50), and effective dose to circulating immune cells (EDIC) were examined by logistic risk regression analysis. The cutoffs of dosimetric parameters were determined by the receiver operating characteristic curve (ROC). RESULTS: A total of 556 patients were included. The incidences of grades 0, 1, 2, 3, and 4 (G4) lymphopenia during dCCRT were 0.2%, 0.5%, 9.7%, 59.7%, and 29.8%, respectively. Their median overall survival (OS) and progression-free survival (PFS) time were 50.2 and 24.3 months, respectively; the incidence of local recurrence and distant metastasis were 36.6% and 31.8%, respectively. Patients once suffering from G4 nadir during radiotherapy had unfavorable OS (HR, 1.28; P = .044) and a higher incidence of distant metastasis (HR, 1.52; P = .013). Furthermore, patients with EDIC ≤8.3Gy plus spleen V0.5 ≤11.1% and bone marrow V10 ≤33.2% were strongly associated with lower risk of G4 nadir (OR, 0.41; P = .004), better OS (HR, 0.71; P = .011) and lower risk of distant metastasis (HR, 0.56; P = .002). CONCLUSIONS: Smaller relative volumes of spleen V0.5 and bone marrow V10 plus lower EDIC were jointly prone to reduce the incidence of G4 nadir during definitive concurrent chemoradiotherapy. This modified therapeutic strategy could be a significant prognostic factor for survival outcomes in ESCC.

Immune characteristics and genetic markers of esophageal cancer by single-cell analysis: implications for immunotherapy.

Background: Esophageal cancer (EC) is one of the most common cancers worldwide. The prognoses for patients with the same stage of EC can vary substantially. The progress of single-cell analysis technology has furthered the understanding of tumor heterogeneity. This paper aimed to apply single-cell analysis to explore the characteristics of the tumor environment of EC and provide a basis for personalized treatment. Methods: The latest gene expression data and clinical follow-up information of single-cell sequencing results of EC samples were downloaded from The Cancer Genome Atlas (TCGA) Genomic Data Commons (GDC) Application Programming Interface (API). A differential gene function analysis of the immune infiltration signature agents in the tumor microenvironment (TME) was performed using bioinformatics analytical methods, and potential molecular targets were sought. Results: We identified specific cell subsets in the EC and paracancerous samples, including panel cells, natural killer (NK) cells, exhausted cluster of differentiation (CD)8+ T cells, CD8+ memory T (Tcm) cells, and effector memory T (Tem) cells, including B cell enrichment in the cancer samples. Differences were detected between B cells and monocytes in stage II and III tumors, which may be related to RNA transcription and degradation. The CXCL8 protein was identified as a valid potential prognostic marker. Conclusions: Cell groups with homogenous cell surface markers exhibit intercellular variations that exert a considerable effect on cell function. Our study will contribute to the understanding of the TME and cellular heterogeneity in EC patients and serve as a valuable resource for in-depth exploration of the pathogenesis of EC and the identification of potential therapeutic targets in the future.

CD161 Characterizes an Inflamed Subset of Cytotoxic T Lymphocytes Associated with Prolonged Survival in Human Papillomavirus-Driven Oropharyngeal Cancer.

Human papillomavirus (HPV)-driven oropharyngeal carcinoma (OPSCC) is distinct from tobacco- or alcohol-associated OPSCC and has a unique immune landscape. Studies have supported the heterogeneity of T cells, accompanied by a broad repertoire of T-cell responses, within tumors driven by HPV infection. However, the phenotype and function of these HPV-related T cells remain unclear. Using a combination of single-cell RNA sequencing, flow cytometry, pharmacologic inhibition, and immunofluorescence staining, we explored the prognostic implication of HPV-related T cells and further validated our findings in two independent cohorts. Cytotoxic T lymphocytes (CTL) within OPSCC displayed a spectrum of transcriptional signatures. Among which, we identified CD161 receptor, encoded by KLRB1, as a potential marker to distinguish the CTL subsets in HPV-positive OPSCC with a divergent evolutionary trajectory. In-depth analysis revealed that CD161+ CTLs exhibited a more robust immune response over the CD161- counterparts and a T cell-inflamed phenotype that could be further reinvigorated by immune-checkpoint blockade. Despite the high expression of exhaustion markers, reinforcement of CD161+ CTL reactivity was expected to boost immune responses, considering their functional reversibility. We further confirmed that the high level of intratumoral CD161+ CTLs associated with a favorable treatment response and prolonged overall survival. Therefore, our research not only provides an insight into the immune landscape of HPV-driven OPSCC but also sheds light on a special subset of CTLs with prognostic and therapeutic significance.

Treatment outcomes of 156 patients with cervical esophageal cancers treated with definitive radiation therapy- A single-institution experience of a rare cancer.

Purpose: Esophageal cancer is the most prevalent malignant tumor. The incidence of cervical esophageal cancer is low and there are insufficient data on the efficacy of radical radiotherapy. The purpose of this study was to clarify the efficacy with radical IFI radiotherapy, to analyze the pattern of initial lymph node metastasis and recurrence under the new lymph node zoning of esophageal cancer. Methods: We reviewed cervical esophageal cancer treated with radical radiotherapy. The inclusion criteria were diagnosis of esophageal cancer by pathology; receiving radical radiotherapy or chemoradiotherapy; tumor location in accordance with definition of cervical esophageal cancer. Three dimensional radiotherapy was used. The target area was IFI. Results: 156 patients entered the final analysis. The proportion of no failure was 42.31%, local esophageal failure was 30.13%, in-field lymph node metastasis was 10.26%, out-field lymph node metastasis was 1.28% and distant organ metastasis was 23.72%, second primary tumor was 2.56%. The median OS and DFS was 49.0 months (35.27-62.73) and 31.0 months (14.47-47.53). The results of initial LN metastasis pattern analysis showed the supraclavicular and upper mediastinum were the main sites of cervical esophageal cancer metastasis. In patients with recurrent LN, the results showed that the cervical, supraclavicle, upper mediastinum and abdomen were the main sites of recurrence. Conclusion: Our study is a retrospective study of a large sample of radical radiotherapy for cervical esophageal cancer. Failure in irradiation field is the main failure pattern. Concurrent radiotherapy and chemotherapy under IFI radiation is a considerable treatment option for cervical esophageal cancer.

Comprehensive analysis of prognostic value of lymph node staging classifications in patients with head and neck squamous cell carcinoma after cervical lymph node dissection.

PURPOSE: To determine the optimal threshold of examined lymph node (ELN) number from cervical lymph node dissection for head and neck squamous cell carcinoma (HNSCC). Further to compare the prognostic value of multiple lymph node classification systems and to determine the most suitable scheme to predict survival. METHODS: A total of 20991 HNSCC patients were included. Odds ratios (ORs) for negative-to-positive node stage migration and hazard ratios (HRs) for survival were fitted using the LOWESS smoother. Structural breakpoints were determined by the Chow test. The R square, C-index, likelihood ratio, and Akaike information criterion (AIC) were used to compare the prognostic abilities among AJCC N stage, number of positive lymph nodes (pN), positive lymph node ratio (LNR) and log odds of positive lymph nodes (LODDS) stages. RESULTS: A minimal threshold ELN number of fifteen had the discriminatory capacities for both stage migration and survival. LODDS stages had the highest R square value (0.208), C-index (0.736) and likelihood ratio (2467) and the smallest AIC value (65874). LODDS stages also showed prognostic value in estimating patients with AJCC N0 stage. A novel staging system was proposed and showed good prognostic performance when stratified by different primary sites. CONCLUSION: Fifteen lymph nodes should be examined for HNSCC patients. LODDS stage allows better prognostic stratification, especially in N0 stage. The proposed staging system may serve as precise evaluation tools to estimate postoperative prognoses.

Targeting CDK7 suppresses super enhancer-linked inflammatory genes and alleviates CAR T cell-induced cytokine release syndrome.

BACKGROUND: Cytokine release syndrome (CRS) is a systemic inflammatory response characterized by the overexpression of inflammatory genes. Controlling CRS is essential for improving the therapeutic effects of chimeric antigen receptor (CAR) engineered T cells. However, current treatment options are limited given the complexity of cytokine interactions so it is important to seek a mild strategy with broad-spectrum inhibition to overcome this challenge. METHODS: Using THZ1, a covalent inhibitor of cyclin-dependent kinase 7 (CDK7), we demonstrated the transcriptional suppression of inflammatory genes in activated macrophages. RNA sequencing and ChIP sequencing were conducted to identify the key target genes of the inflammatory response. Pathogen- and CAR T cell-induced CRS models were also established to assess the efficacy and safety of targeting CDK7. RESULTS: CDK7 blockade attenuated cytokine release, mitigated hyperinflammatory states and rescued mice from lethal CRS. Targeting CDK7 preferentially suppressed a set of inflammatory genes, of which STAT1 and IL1 were the key targets associated with super enhancers. Furthermore, we confirmed the potent efficacy of THZ1 in alleviating the CRS induced by CAR T cell infusion without causing tissue injury or impairing antitumor effects. CONCLUSIONS: Our work indicates the CDK7-dependent transcription addiction of inflammatory genes. Targeting CDK7 is a promising strategy for treating CRS by inhibiting multiple cytokines.

Transcriptome and miRNome Analysis Provide New Insight Into Host Lipid Accumulation, Innate Immunity, and Viral Persistence in Hepatitis C Virus Infection in vitro.

Hepatitis C virus (HCV)-host cell interaction during infection disturbs cellular homeostasis and culminates in pathological consequences. The processes could be first embodied in gene expression of HCV-infected cells. Here, we investigated transcriptome and miRNA expression (miRNome) alterations in HCV-infected Huh7 cells at 12, 36, and 60 h after infection to systematically explore host responses. The number of deregulated genes in the HCV-infected cells increased with infection duration. The altered biological processes at 36 h were mainly associated with stress and inflammatory response, whereas the most enriched processes at 60 h were predominantly linked to lipid metabolism. Notably, the key genes that participated in lipogenesis were downregulated, and conversely, the genes implicated in fatty acid beta-oxidation were upregulated. Reduced expression of the key genes involved in lipoprotein assembly and secretion pointed to a decreased requirement for and export of lipids, leading to lipid accumulation in HCV-infected hepatocytes. Fluctuation in the expression of host factors, innate immunity genes and transcription factors provided insight into host-directed mechanisms to control viral replication. Furthermore, miRNome presented a comprehensive expression profile of miRNAs in HCV-infected Huh7 cells. The integrated analysis of transcriptome and miRNome suggested that deregulated miR-483, miR-1303, miR-1260a, miR-27a∗, and miR-21∗ directly regulated lipid metabolical genes at 60 h. The decreased miR-122 at 60 h was indirectly involved in lipid metabolism and is expected to attenuate rampant replication of HCV and potentially contribute to viral persistence. Our results will help to gain a comprehensive understanding of the molecular mechanisms implicated in HCV-induced pathogenesis.

Human papillomavirus (HPV) in Chinese oropharyngeal squamous cell carcinoma (OPSCC): A strong predilection for the tonsil.

OBJECTIVE: Compared with Occident's data, the incidence of Human papillomavirus (HPV)-driven oropharyngeal squamous cell carcinomas (OPSCCs) had been reported as relatively low in Mainland China. The objective of this study was to report the integrated prevalence of HPV and Epstein-Barr virus (EBV), and further evaluate the different behaviors of HPV-positive and -negative OPSCCs in eastern China. METHODS: In a cohort of 170 nonmetastatic OPSCCs treated from January 2007 to July 2019, p16 protein expression, HPV genotypes, and Epstein-Barr virus-encoded RNA (EBER) were determined by immunohistochemistry (IHC) and in situ hybridization (ISH). The clinical and pathologic findings were further collected and analyzed to comprehensively reveal the behaviors of Chinese OPSCCs. RESULTS: Out of the 170 tumor tissues evaluated, 57.6% (98) samples had positive p16 expressions. A total of 65.1% (99/152) samples had positive HPV genotypes, besides HPV16 (92/152), HPV11, 18, 33, 53, and 58 were also detected. The positive rate of EBER was 7.2% (9/124), and the co-infection rate of EBV/HPV was 4.0%. Related to the unequal distributions of p16 expression, HPV-related tumors arisen from tonsillar and non-tonsillar accounted for 68.8% (75/109) and 37.7% (23/61) of their cases, respectively (P < .001). With a median follow-up time of 13.1 months, significant survival advantages of HPV-related OSPCC were observed; 1-year OS, PFS, RFS, and MFS were 83.2% vs 96.7% (P < .001), 71.6% vs 96.2% (P < .001), 77.7% vs 96.2% (P = .002), and 90.4% vs 100.0% (P = .024) in p16-negative and -positive cases, respectively. CONCLUSIONS: The relative percent of HPV-positive OPSCCs in this study is close to the positive rate in many Western countries and a strong predilection was discovered for the tonsillar. The EBV infection and co-infection of HPV/EBV were largely low. The prognosis of HPV-positive OSPCCs was more favorable than its negative counterpart.

MicroRNA­200a suppresses migration and invasion and enhances the radiosensitivity of NSCLC cells by inhibiting the HGF/c­Met signaling pathway.

Hepatocyte growth factor (HGF), an activator of the c­Met signaling pathway, is involved in tumor invasiveness, metastasis and radiotherapy resistance. In the present study, a novel HGF regulatory pathway in lung cancer involving micro-RNAs (miRNAs/miR) is described. Immunohistochemical staining and western blot analyses demonstrated that HGF was upregulated and associated with miR­200a downregulation in non­small cell lung cancer (NSCLC) samples compared with normal lung tissues. The association between HGF and miR­200a was associated with the degree of tumor malignancy and cell migration and invasion. miR­200a negatively regulated HGF expression by targeting the 3'­untranslated region of the HGF mRNA. miR­200a overexpression induced HGF downregulation, decreased NSCLC cell migration and invasion, promoted apoptosis, and decreased cell survival in A549 and H1299 cells in response to ionizing radiation. The present results revealed a previously uncharacterized role of miRNA­200a in regulating tumor malignancy and radiosensitivity by suppressing HGF expression, a key factor in the HGF/c­Met pathway.

RAD51 interconnects between DNA replication, DNA repair and immunity.

RAD51, a multifunctional protein, plays a central role in DNA replication and homologous recombination repair, and is known to be involved in cancer development. We identified a novel role for RAD51 in innate immune response signaling. Defects in RAD51 lead to the accumulation of self-DNA in the cytoplasm, triggering a STING-mediated innate immune response after replication stress and DNA damage. In the absence of RAD51, the unprotected newly replicated genome is degraded by the exonuclease activity of MRE11, and the fragmented nascent DNA accumulates in the cytosol, initiating an innate immune response. Our data suggest that in addition to playing roles in homologous recombination-mediated DNA double-strand break repair and replication fork processing, RAD51 is also implicated in the suppression of innate immunity. Thus, our study reveals a previously uncharacterized role of RAD51 in initiating immune signaling, placing it at the hub of new interconnections between DNA replication, DNA repair, and immunity.

Replication stress induced site-specific phosphorylation targets WRN to the ubiquitin-proteasome pathway.

Faithful and complete genome replication in human cells is essential for preventing the accumulation of cancer-promoting mutations. WRN, the protein defective in Werner syndrome, plays critical roles in preventing replication stress, chromosome instability, and tumorigenesis. Herein, we report that ATR-mediated WRN phosphorylation is needed for DNA replication and repair upon replication stress. A serine residue, S1141, in WRN is phosphorylated in vivo by the ATR kinase in response to replication stress. ATR-mediated WRN S1141 phosphorylation leads to ubiquitination of WRN, facilitating the reversible interaction of WRN with perturbed replication forks and subsequent degradation of WRN. The dynamic interaction between WRN and DNA is required for the suppression of new origin firing and Rad51-dependent double-stranded DNA break repair. Significantly, ATR-mediated WRN phosphorylation is critical for the suppression of chromosome breakage during replication stress. These findings reveal a unique role for WRN as a modulator of DNA repair, replication, and recombination, and link ATR-WRN signaling to the maintenance of genome stability.

FANCD2 influences replication fork processes and genome stability in response to clustered DSBs.

Fanconi Anemia (FA) is a cancer predisposition syndrome and the factors defective in FA are involved in DNA replication, DNA damage repair and tumor suppression. Here, we show that FANCD2 is critical for genome stability maintenance in response to high-linear energy transfer (LET) radiation. We found that FANCD2 is monoubiquitinated and recruited to the sites of clustered DNA double-stranded breaks (DSBs) specifically in S/G2 cells after high-LET radiation. Further, FANCD2 facilitated the repair of clustered DSBs in S/G2 cells and proper progression of S-phase. Furthermore, lack of FANCD2 led to a reduced rate of replication fork progression and elevated levels of both replication fork stalling and new origin firing in response to high-LET radiation. Mechanistically, FANCD2 is required for correct recruitment of RPA2 and Rad51 to the sites of clustered DSBs and that is critical for proper processing of clustered DSBs. Significantly, FANCD2-decifient cells exhibited defective chromosome segregation, elevated levels of chromosomal aberrations, and anchorage-independent growth in response to high-LET radiation. These findings establish FANCD2 as a key factor in genome stability maintenance in response to high-LET radiation and as a promising target to improve cancer therapy.

Nonenzymatic role for WRN in preserving nascent DNA strands after replication stress.

WRN, the protein defective in Werner syndrome (WS), is a multifunctional nuclease involved in DNA damage repair, replication, and genome stability maintenance. It was assumed that the nuclease activities of WRN were critical for these functions. Here, we report a nonenzymatic role for WRN in preserving nascent DNA strands following replication stress. We found that lack of WRN led to shortening of nascent DNA strands after replication stress. Furthermore, we discovered that the exonuclease activity of MRE11 was responsible for the shortening of newly replicated DNA in the absence of WRN. Mechanistically, the N-terminal FHA domain of NBS1 recruits WRN to replication-associated DNA double-stranded breaks to stabilize Rad51 and to limit the nuclease activity of its C-terminal binding partner MRE11. Thus, this previously unrecognized nonenzymatic function of WRN in the stabilization of nascent DNA strands sheds light on the molecular reason for the origin of genome instability in WS individuals.

Mechanisms of increased risk of tumorigenesis in Atm and Brca1 double heterozygosity.

BACKGROUND: Both epidemiological and experimental studies suggest that heterozygosity for a single gene is linked with tumorigenesis and heterozygosity for two genes increases the risk of tumor incidence. Our previous work has demonstrated that Atm/Brca1 double heterozygosity leads to higher cell transformation rate than single heterozygosity. However, the underlying mechanisms have not been fully understood yet. In the present study, a series of pathways were investigated to clarify the possible mechanisms of increased risk of tumorigenesis in Atm and Brca1 heterozygosity. METHODS: Wild type cells, Atm or Brca1 single heterozygous cells, and Atm/Brca1 double heterozygous cells were used to investigate DNA damage and repair, cell cycle, micronuclei, and cell transformation after photon irradiation. RESULTS: Remarkable high transformation frequency was confirmed in Atm/Brca1 double heterozygous cells compared to wild type cells. It was observed that delayed DNA damage recognition, disturbed cell cycle checkpoint, incomplete DNA repair, and increased genomic instability were involved in the biological networks. Haploinsufficiency of either ATM or BRCA1 negatively impacts these pathways. CONCLUSIONS: The quantity of critical proteins such as ATM and BRCA1 plays an important role in determination of the fate of cells exposed to ionizing radiation and double heterozygosity increases the risk of tumorigenesis. These findings also benefit understanding of the individual susceptibility to tumor initiation.

Hemizygosity for Atm and Brca1 influence the balance between cell transformation and apoptosis.

BACKGROUND: In recent years data from both mouse models and human tumors suggest that loss of one allele of genes involved in DNA repair pathways may play a central role in genomic instability and carcinogenesis. Additionally several examples in mouse models confirmed that loss of one allele of two functionally related genes may have an additive effect on tumor development. To understand some of the mechanisms involved, we examined the role of monoallelic loss or Atm and Brca1 on cell transformation and apoptosis induced by radiation. METHODS: Cell transformation and apoptosis were measured in mouse embryo fibroblasts (MEF) and thymocytes respectively. Combinations of wild type and hemizygous genotypes for ATM and BRCA1 were tested in various comparisons. RESULTS: Haploinsufficiency of either ATM or BRCA1 resulted in an increase in the incidence of radiation-induced transformation of MEF and a corresponding decrease in the proportion of thymocytes dying an apoptotic death, compared with cells from wild-type animals. Combined haploinsufficiency for both genes resulted in an even larger effect on apoptosis. CONCLUSIONS: Under stress, the efficiency and capacity for DNA repair mediated by the ATM/BRCA1 cell signalling network depends on the expression levels of both proteins.