OBJECTIVE: Since the outbreak of Coronavirus Disease 2019 (COVID-19) in December 2019, various digestive symptoms have been frequently reported in patients infected with the virus. In this study, we aimed to further investigate the prevalence and outcomes of COVID-19 patients with digestive symptoms. METHODS: In this descriptive, cross-sectional, multicenter study, we enrolled confirmed patients with COVID-19 who presented to 3 hospitals from January 18, 2020, to February 28, 2020. All patients were confirmed by real-time polymerase chain reaction and were analyzed for clinical characteristics, laboratory data, and treatment. Data were followed up until March 18, 2020. RESULTS: In the present study, 204 patients with COVID-19 and full laboratory, imaging, and historical data were analyzed. The average age was 52.9 years (SD ± 16), including 107 men and 97 women. Although most patients presented to the hospital with fever or respiratory symptoms, we found that 103 patients (50.5%) reported a digestive symptom, including lack of appetite (81 [78.6%] cases), diarrhea (35 [34%] cases), vomiting (4 [3.9%] cases), and abdominal pain (2 [1.9%] cases). If lack of appetite is excluded from the analysis (because it is less specific for the gastrointestinal tract), there were 38 total cases (18.6%) where patients presented with a gastrointestinal-specific symptom, including diarrhea, vomiting, or abdominal pain. Patients with digestive symptoms had a significantly longer time from onset to admission than patients without digestive symptoms (9.0 days vs 7.3 days). In 6 cases, there were digestive symptoms, but no respiratory symptoms. As the severity of the disease increased, digestive symptoms became more pronounced. Patients with digestive symptoms had higher mean liver enzyme levels, lower monocyte count, longer prothrombin time, and received more antimicrobial treatment than those without digestive symptoms. DISCUSSION: We found that digestive symptoms are common in patients with COVID-19. Moreover, these patients have a longer time from onset to admission, evidence of longer coagulation, and higher liver enzyme levels. Clinicians should recognize that digestive symptoms, such as diarrhea, are commonly among the presenting features of COVID-19 and that the index of suspicion may need to be raised earlier in at-risk patients presenting with digestive symptoms. However, further large sample studies are needed to confirm these findings.

Little is known of the patterns of expression of ACE2 and TMPRSS2 or the clinical characteristics of COVID-19 in patients with COVID-19 and colorectal cancer. We found in both bulk and single-cell RNA-seq profiles that ACE2 and TMPRSS2 were expressed at high levels on tumor and normal colorectal epithelial tissues. Clinically, patients with colorectal cancer and COVID-19 were more likely to have lymphopenia, higher respiratory rate, and high hypersensitive C-reactive protein levels than matched patients with COVID-19 but without cancer. These results suggest that patients with colorectal cancer may be particularly susceptible to SARS-CoV-2 infection. Further mechanistic studies are needed to support our findings.

Tumor-infiltrating T cells recognize, attack, and clear tumor cells, playing a central role in antitumor immune response. However, certain immune cells can impair this response and help tumor immune escape. Therefore, exploring the factors that influence T-cell infiltration is crucial to understand tumor immunity and improve therapeutic effect of cancer immunotherapy. The use of single-cell RNA sequencing (scRNA-seq) allows the high-resolution analysis of the precise composition of immune cells with different phenotypes and other microenvironmental factors, including non-immune stromal cells and the related molecules in the tumor microenvironment of various cancer types. In this review, we summarized the research progress on T-cell infiltration and the crosstalk of other stromal cells and cytokines during T-cell infiltration using scRNA-seq to provide insights into the mechanisms regulating T-cell infiltration and contribute new perspectives on tumor immunotherapy.

Recent oncological research has intensely focused on the tumor immune microenvironment (TME), particularly the functions of CD4 + T lymphocytes. CD4+ T lymphocytes have been implicated in antigen presentation, cytokine release, and cytotoxicity, suggesting their contribution to the dynamics of the TME. Furthermore, the application of single-cell sequencing has yielded profound insights into the phenotypic diversity and functional specificity of CD4+ T cells in the TME. In this review, we discuss the current findings from single-cell analyses, emphasizing the heterogeneity of CD4+ T cell subsets and their implications in tumor immunology. In addition, we review the critical signaling pathways and molecular networks underpinning CD4+ T cell activities, thereby offering novel perspectives on therapeutic targets and strategies for cancer treatment and prognosis.

The relationship between the immune cell and tumor occurrence and progression remains unclear. Profiling alterations in the tumor immune microenvironment (TIME) at high resolution is crucial to identify factors influencing cancer progression and enhance the effectiveness of immunotherapy. However, traditional sequencing methods, including bulk RNA sequencing, exhibit varying degrees of masking the cellular heterogeneity and immunophenotypic changes observed in early and late-stage tumors. Single-cell RNA sequencing (scRNA-seq) has provided significant and precise TIME landscapes. Consequently, this review has highlighted TIME cellular and molecular changes in tumorigenesis and progression elucidated through recent scRNA-seq studies. Specifically, we have summarized the cellular heterogeneity of TIME at different stages, including early, late, and metastatic stages. Moreover, we have outlined the related variations that may promote tumor occurrence and metastasis in the single-cell era. The widespread applications of scRNA-seq in TIME will comprehensively redefine the understanding of tumor biology and furnish more effective immunotherapy strategies.

Purpose: Inflammatory markers have been widely used in various cancers, but rarely in nasopharyngeal carcinoma (NPC). Here, we evaluated the prognostic value of pretreatment neutrophil-to-lymphocyte ratio (NLR), platelet-lymphocyte-ratio (PLR), systemic immune index (SII), and systemic inflammation response index (SIRI) on NPC in the intensity-modulated radiotherapy (IMRT) era. Methods: We retrospectively analyzed data from NPC patients from the Renmin Hospital of Wuhan University, between January 2012 and July 2020. We used Chi-square test or Fisher’s exact test to compare the baseline characteristics, then applied Kaplan–Meier (K-M) survival analysis to compare the overall survival (OS) and progression-free survival (PFS) rates. Multivariate Cox proportional risk models were applied to identify independent prognostic factors. Results: We enrolled a total of 342 NPC patients and found optimal cut-off values of 2.65, 184.91, 804.08, and 1.34 for NLR, PLR, SII, and SIRI, respectively. K-M survival analysis revealed that high NLR, PLR, SII, and SIRI were significantly associated with worse OS and PFS relative to those in the low groups. Results from univariate Cox analysis showed that clinical, T, and M stages, as well as NLR, PLR, SII, and SIRI were associated with OS, whereas age, alongside the aforementioned parameters, was associated with PFS. Moreover, multivariate Cox analysis showed that age ≥ 49 years (HR=2.48, 95% CI=1.21– 5.05, P=0.013) and M1 stage (HR=3.84, 95% CI=1.52– 9.73, P=0.013) were independent prognostic factors for OS, whereas SIRI ≥ 1.34 (HR=1.91, 95% CI=1.05– 3.47, P=0.034) and M1 stage (HR=2.91, 95% CI=1.44– 5.86, P=0.003) were independent prognostic factors for PFS. Conclusion: Overall, our findings indicated that high NLR, PLR, SII, and SIRI were significantly associated with poor OS and PFS in NPC patients. High SIRI may be an independent risk factor for PFS of NPC patients in the IMRT era.