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Sex is known to be an important factor in the incidence, progression, and outcome of cancer. A better understanding of the underlying mechanisms could help improve cancer prevention and treatment. Here, we demonstrated a crucial role of antitumor immunity in the sex differences in cancer. Consistent with observations in human cancers, male mice showed accelerated tumor progression compared with females, but these differences were not observed in immunodeficient mice. Androgen signaling suppressed T-cell immunity against cancer in males. Mechanistically, androgen-activated androgen receptor upregulated expression of USP18, which inhibited TAK1 phosphorylation and the subsequent activation of NF-κB in antitumor T cells. Reduction of testosterone synthesis by surgical castration or using the small-molecular inhibitor abiraterone significantly enhanced the antitumor activity of T cells in male mice and improved the efficacy of anti–PD-1 immunotherapy. Together, this study revealed a novel mechanism contributing to sex differences in cancer. These results indicate that inhibition of androgen signaling is a promising approach to improve the efficacy of immunotherapy in males.Significance:Androgen signaling induces immunosuppression in cancer by blocking T-cell activity through upregulation of USP18 and subsequent inhibition of NF-κB activity, providing a targetable axis to improve antitumor immunity in males.

Supplementary Figure 1 and 2 Legends

Clinical characteristics for the NSCLC cohort analyzed the correlation between testosterone levels, prognosis and T cell infiltration

Clinical characteristics for the NSCLC cohort analyzed sex difference of survival in patients treated with anti-PD-1 antibody

RNA-seq Data

Clinical characteristics for melanoma cohort analyzed sex difference of survival in patients treated with anti-PD-1 antibody

ATAC-seq Data

Supplementary Figure 1

Sex is known to be an important factor in the incidence, progression, and outcome of cancer. A better understanding of the underlying mechanisms could help improve cancer prevention and treatment. Here, we demonstrated a crucial role of antitumor immunity in the sex differences in cancer. Consistent with observations in human cancers, male mice showed accelerated tumor progression compared with females, but these differences were not observed in immunodeficient mice. Androgen signaling suppressed T-cell immunity against cancer in males. Mechanistically, androgen-activated androgen receptor upregulated expression of USP18, which inhibited TAK1 phosphorylation and the subsequent activation of NF-κB in antitumor T cells. Reduction of testosterone synthesis by surgical castration or using the small-molecular inhibitor abiraterone significantly enhanced the antitumor activity of T cells in male mice and improved the efficacy of anti–PD-1 immunotherapy. Together, this study revealed a novel mechanism contributing to sex differences in cancer. These results indicate that inhibition of androgen signaling is a promising approach to improve the efficacy of immunotherapy in males.Significance:Androgen signaling induces immunosuppression in cancer by blocking T-cell activity through upregulation of USP18 and subsequent inhibition of NF-κB activity, providing a targetable axis to improve antitumor immunity in males.

Supplementary Figure 2

Long noncoding RNAs (lncRNA) are involved in tumorigenesis and drug resistance. However, the roles and underlying mechanisms of lncRNAs in colorectal cancer are still unknown. In this work, through transcriptomic profiling analysis of 21 paired tumor and normal samples, we identified a novel colorectal cancer–related lncRNA, MNX1-AS1. MNX1-AS1 expression was significantly upregulated in colorectal cancer and associated with poor prognosis. In vitro and in vivo gain- and loss-of-function experiments showed that MNX1-AS1 promotes the proliferation of colorectal cancer cells. MNX1-AS1 bound to and activated Y-box-binding protein 1 (YB1), a multifunctional RNA/DNA-binding protein, and prevented its ubiquitination and degradation. A marked overlap between genes that are differentially expressed in MNX1-AS1 knockdown cells and transcriptional targets of YB1 was observed. YB1 knockdown mimicked the loss of viability phenotype observed upon depletion of MNX1-AS1. In addition, MYC bound the promoter of the MNX1-AS1 locus and activated its transcription. In vivo experiments showed that ASO inhibited MNX1-AS1, which suppressed the proliferation of colorectal cancer cells in both cell-based and patient-derived xenograft models. Collectively, these findings suggest that the MYC–MNX1-AS1–YB1 axis might serve as a potential biomarker and therapeutic target in colorectal cancer. Significance: This study highlights the discovery of a novel colorectal cancer biomarker and therapeutic target, MNX1-AS1, a long noncoding RNA that drives proliferation via a MYC/MNX1-AS1/YB1 signaling pathway.

The genetic events occurring in recurrent nasopharyngeal carcinoma (rNPC) are poorly understood. Here, we performed whole-genome and whole-exome sequencing in 55 patients with rNPC and 44 primarily diagnosed NPC (pNPC), with 7 patients having paired rNPC and pNPC samples. Previously published pNPC exome data were integrated for analysis. rNPC and pNPC tissues had similar mutational burdens, however, the number of clonal mutations was increased in rNPC samples. TP53 and three NF-κB pathway components (TRAF3, CYLD, and NFKBIA) were significantly mutated in both pNPC and rNPC. Notably, mutations in TRAF3, CYLD, and NFKBIA were all clonal in rNPC, however, 55.6% to 57.9% of them were clonal in pNPC. In general, the number of clonal mutations in NF-κB pathway–associated genes was significantly higher in rNPC than in pNPC. The NF-κB mutational clonality was selected and/or enriched during NPC recurrence. The amount of NF-κB translocated to the nucleus in samples with clonal NF-κB mutants was significantly higher than that in samples with subclonal NF-κB mutants. Moreover, the nuclear abundance of NF-κB protein was significantly greater in pNPC samples with locoregional relapse than in those without relapse. Furthermore, high nuclear NF-κB levels were an independent negative prognostic marker for locoregional relapse-free survival in pNPC. Finally, inhibition of NF-κB enhanced both radiosensitivity and chemosensitivity in vitro and in vivo. In conclusion, NF-κB pathway activation by clonal mutations plays an important role in promoting the recurrence of NPC. Moreover, nuclear accumulation of NF-κB is a prominent biomarker for predicting locoregional relapse-free survival. Significance: This study uncovers genetic events that promote the progression and recurrence of nasopharyngeal carcinoma and has potential prognostic and therapeutic implications. See related commentary by Sehgal and Barbie, p. 5915

Background & Aims—Small cell carcinoma of the oesophagus (SCCE) is a deadly malignancy but its genetic characteristics remain unknown and treatment is commonly adopted from therapies for its histologically identical counterpart, small cell lung cancer (SCLC). We conducted a large-scale genomic analysis of SCCE to determine the mutational landscape of this deadly disease. Methods—We performed whole-exome sequence of tumour and para normal esophageal tissues from 55 patients with SCCE who underwent surgery at seven institutions in China. Comprehensive analyses were carried out to identify key genetic events in SCCE, including significant mutations, copy number variation, pathway disruption. We also performed ultra-deep targeted sequencing on 20 specimens and microarray assays on 24 specimens to validate somatic mutations and copy number variations respectively. Using an unsupervised hierarchical clustering approach, the genomic characteristics of SCCE were compared with other types of malignancies including oesophageal squamous cell carcinoma, oesophageal adenocarcinoma and et al. In vitro proliferation and migration assays were conducted to assess the function of PDE3A. Results—The mutational spectrum of SCCE was dominated by C>T/G>A transitions and the mutational signatures classified the patients into 3 groups. We identified three novel significantly mutated genes (PDE3A, PTPRM and CBLN2) and mutations in five other well-known tumour-associated genes (TP53, RB1, NOTCH1, FAT1 and FBXW7). Non-silent alterations of chromatin remodeling genes were detected in 96.4%. Moreover, pathway enrichment analysis revealed that genes involved in the cell cycle, p53, Notch and Wnt signaling were frequently altered in SCCE. Mutations in NOTCH family correlated with shorter overall survival. Furthermore, comparison analysis of mutation signatures revealed that SCCE tumours were more closely related to oesophageal squamous cell carcinoma, rather than oesophageal adenocarcinoma and SCLC, suggesting that current therapies for SCCE may be inadequate. Functional characterizations suggested that PDE3A acts as a novel oncogene. Conclusions—Our findings reveal key somatic alterations in SCCE, and provide insights to better understand the pathogenesis of SCCE and to develop better treatment strategies for patients with the condition. Citation Format: Feng Wang, Dongbing Liu, Qi Zhao, Gang Chen, Xinming Liu, Yingnan Wang, Hong Su, Yanru Qin, Yifu He, Qingfeng Zou, Yanhui Liu, Youen Lin, Hui Sheng, Jiajia Hu, Zexian Liu, Zhixiang Zuo, Jinxin Bei, Ruihua Xu. The genomic landscape of small cell carcinoma of the oesophagus [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2345.

As the daily oscillation in physiological processes, circadian is critical for health while disruption of the circadian rhythm has been associated with cancer in humans. Generally, circadian rhythm was proposed to play important roles in tumor suppression, while there were also evidences that disruption of canonical circadian pathway have anti-cancer effects. In this study, we systematically analyzed the aberrances including mutation, somatic copy number alternation, differential DNA methylation and differential expression of circadian genes across cancers based on TCGA data. It is observed that core circadian network genes (CCNGs) such as PER1/2/3, CLOCK, CRY1/2, ARNTL were highly mutated in a number of cancers such as uterine corpus endometrial carcinoma, skin cutaneous melanoma, stomach adenocarcinoma and colon adenocarcinoma. Generally, the expression for the majority of CCNGs was down regulated in a variety of the cancers such as bladder urothelial carcinoma, head and neck squamous cell carcinoma, breast invasive carcinoma, cervical and endocervical cancers, prostate adenocarcinoma, glioblastoma multiforme and stomach adenocarcinoma, while the expression of a number of CCNGs were related with overall survival in various cancers. The alternations of somatic copy number and DNA methylation were observed to be consistent with the differential expression of these CCNGs. Furthermore, the PCA based circadian gene expression signature was found to be related with the overall survivals and immunophenotypes among cancers, which indicated that circadian rhythm might play critical roles in regulation of immune signaling state in tumor environment. Taken together, our study provided comprehensive analyses of the aberrances and functional roles of circadian genes in cancer, while the results should be helpful for further investigation of the molecular mechanisms and therapy development for cancer. Citation Format: Zexian Liu, Huan Lin, Zekun Liu, Kai Yu, Qi Zhao, Xiaolong Zhang, Yan Wang, Zhixiang Zuo. The dysregulation of circadian genes across cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2263.