Comprehensive analysis of 33 human cancers reveals clinical implications and immunotherapeutic value of the solute carrier family 35 member A2.

Background: Solute carrier family 35 member A2 (SLC35A2), which belongs to the SLC35 solute carrier family of human nucleoside sugar transporters, has shown regulatory roles in various tumors and neoplasms. However, the function of SLC35A2 across human cancers remains to be systematically assessed. Insights into the prediction ability of SLC35A2 in clinical practice and immunotherapy response remains limited. Materials and methods: We obtained the gene expression and protein levels of SLC35A2 in a variety of tumors from Molecular Taxonomy of Breast Cancer International Consortium, The Cancer Genome Atlas, Gene Expression Omnibus, Chinese Glioma Genome Atlas, and Human Protein Atlas databases. The SLC35A2 level was validated by immunohistochemistry. The predictive value for prognosis was evaluated by Kaplan-Meier survival and Cox regression analyses. Correlations between SLC35A2 expression and DNA methylation, genetic alterations, tumor mutation burden (TMB), microsatellite instability (MSI), and tumor microenvironment were performed using Spearman's correlation analysis. The possible downstream pathways of SLC35A2 in different human cancers were explored using gene set variation analysis. The potential role of SLC35A2 in the tumor immune microenvironment was evaluated via EPIC, CIBERSORT, MCP-counter, CIBERSORT-ABS, quanTIseq, TIMER, and xCell algorithms. The difference in the immunotherapeutic response of SLC35A2 under different expression conditions was evaluated by the tumor immune dysfunction and exclusion (TIDE) score as well as four independent immunotherapy cohorts, which includes patients with bladder urothelial carcinoma (BLCA, N = 299), non-small cell lung cancer (NSCLC, N = 72 and N = 36) and skin cutaneous melanoma (SKCM, N = 25). Potential drugs were identified using the CellMiner database and molecular docking. Results: SLC35A2 exhibited abnormally high or low expression in 23 cancers and was significantly associated with the prognosis. In various cancers, SLC35A2 expression and mammalian target of rapamycin complex 1 signaling were positively correlated. Multiple algorithmic immune infiltration analyses suggested an inverse relation between SLC35A2 expression and infiltrating immune cells, which includes CD4+T cells, CD8+T cells, B cells, and natural killer cells (NK) in various tumors. Furthermore, SLC35A2 expression was significantly correlated with pan-cancer immune checkpoints, TMB, MSI, and TIDE genes. SLC35A2 showed significant predictive value for the immunotherapy response of patients with diverse cancers. Two drugs, vismodegib and abiraterone, were identified, and the free binding energy of cytochrome P17 with abiraterone was higher than that of SLC35A2 with abiraterone. Conclusion: Our study revealed that SLC35A2 is upregulated in 20 types of cancer, including lung adenocarcinoma (LUAD), breast invasive carcinoma (BRCA), colon adenocarcinoma (COAD), and lung squamous cell carcinoma (LUSC). The upregulated SLC35A2 in five cancer types indicates a poor prognosis. Furthermore, there was a positive correlation between the overexpression of SLC35A2 and reduced lymphocyte infiltration in 13 cancer types, including BRCA and COAD. Based on data from several clinical trials, patients with LUAD, LUSC, SKCM, and BLCA who exhibited high SLC35A2 expression may experience improved immunotherapy response. Therefore, SLC35A2 could be considered a potential predictive biomarker for the prognosis and immunotherapy efficacy of various tumors. Our study provides a theoretical basis for further investigating its prognostic and therapeutic potentials.

Pembrolizumab for the better treatment of EGFR-mutant T790M-negative advanced lung adenocarcinoma patients than dual treatment of pemetrexed plus platinum after tyrosine kinase inhibitor treatment failure.

BACKGROUND: The treatment of lung cancer patients, especially those with epidermal growth factor receptor (EGFR)-mutant T790M-negative adenocarcinoma, after first- or second-line tyrosine kinase inhibitor (TKI) treatment failure is challenging due to the poor prognosis and limited effectiveness of platinum two-drug chemotherapy or chemotherapy plus anti-angiogenesis therapy. It is well-known that pembrolizumab monotherapy exhibits low toxicity and long-term survival, but it is unknown in these patients. METHODS: From September 2018 to March 2021, 460 patients in Jiangmen Central Hospital were included and 82 patients with disease progression in lung adenocarcinoma who remained T790M-negative on the second biopsy were screened. Two groups were divided according to treatment status, and simple random sampling was performed to obtain 32 cases respectively. The safety of the patients was subsequently evaluated by telephone follow-up. RESULTS: The objective response rate (ORR) and disease control rate (DCR) in the pembrolizumab group were 15.63% and 53.13%. In the chemotherapy group, the ORR was 8.33% and the DCR was 25% (P<0.05). In the pembrolizumab group, the progression-free survival (PFS) [14.65 months, 95% confidence interval (CI): 13.03 to 16.28] was significantly higher than that of the control group (9.54 months, 95% CI: 8.43 to 10.65) (P<0.05). In the univariate analysis, programmed cell death protein 1 ligand (PD-L1) expression, smoking status, gender, and whether first-line chemotherapy was associated with survival. In the multivariate analysis, gender [P=0.001; hazard ratio (HR) 10.98, 95% CI: 2.49-46.67], first-line chemotherapy (P=0.037; HR 4.5, 95% CI: 1.1-4.81), and PD-L1 expression (P=0.039; HR 0.16, 95% CI: 0.04-0.68) were correlated with patient survival. Grade 3 or grade 4 treatment-related adverse events were not found in the pembrolizumab group, while 2 cases of grade 3 or 4 treatment-related adverse events occurred in the control group. CONCLUSIONS: In advanced lung adenocarcinoma patients with EGFR-mutant T790M-negative after TKI treatment, pembrolizumab had a higher ORR and PFS. Pembrolizumab in women with first-line chemotherapy and PD-L1 ≥25% of those patients may have a good response and a low rate of adverse reactions. A multicenter, prospective, evidence-based study of pembrolizumab salvage therapy in those patients is warranted for posterior line treatment.

A Novel Signature Integrated of Immunoglobulin, Glycosylation and Anti-Viral Genes to Predict Prognosis for Breast Cancer.

Background: Aberrant glycosylation is significantly related to the occurrence, progression, metastasis, and drug resistance of tumors. It is essential to identify glycosylation and related genes with prognostic value for breast cancer. Objective: We aimed to construct and validate a prognostic model based on glycosylation and related genes, and further investigate its prognosis values in validation set and external independent cohorts. Materials and Methods: The transcriptome and clinical data of breast cancer patients were downloaded from The Cancer Genome Atlas (TCGA, n = 1072), Molecular Taxonomy of Breast Cancer International Consortium (METABRIC, n = 1451), and GSE2741 (n = 120). Glycosylation-related genes were downloaded from the Genecards website. Differentially expressed glycosylation-related geneswere identified by comparing the tumor tissues with the adjacent tissues. The TCGA data were randomly divided into training set and validation set in a 1:1 ratio for further analysis. The glycosylation risk-scoring prognosis model was constructed by univariate and multivariate Cox regression analysis, followed by confirmation in TCGA validation, METABRIC, and GEO datasets. Gene set enrichment analysis (GSEA) and Gene ontology analysis for identifying the affected pathways in the high- and low-risk groups were performed. Results: We attained 1072 breast cancer samples from the TCGA database and 786 glycosylation genes from the Genecards website. A signature contains immunoglobulin, glycosylation and anti-viral related genes was constructed to separate BRCA patients into two risk groups. Low-risk patients had better overall survival than high-risk patients (p < 0.001). A nomogram was constructed with risk scores and clinical characteristics. The area under time-dependent ROC curve reached 0.764 at 1 year, 0.744 at 3 years, and 0.765 at 5 years in the training set. Subgroup analysis showed differences in OS between the high- and low-risk patients in different subgroups. Moreover, the risk score was confirmed as an independent prognostic indicator of BRCA patients and was potentially correlated with immunotherapy response and drug sensitivity. Conclusion: We identified a novel signature integrated of immunoglobulin (IGHA2), glycosylation-related (SLC35A2) and anti-viral gene (BST2) that was an independent prognostic indicator for BRCA patients. The risk-scoring model could be used for predicting prognosis and immunotherapy in BRCA, thus providing a powerful instrument for combating BRCA.

LINC00173.v1 promotes angiogenesis and progression of lung squamous cell carcinoma by sponging miR-511-5p to regulate VEGFA expression.

BACKGROUND: Anti-angiogenic therapy represents a promising strategy for non-small-cell lung cancer (NSCLC) but its application in lung squamous cell carcinoma (SQC) is limited due to the high-risk adverse effects. Accumulating evidence indicates that long noncoding RNAs (lncRNAs) mediate in tumor progression by participating in the regulation of VEGF in NSCLC, which might guide the development of new antiangiogenic strategies. METHODS: Differential lncRNA expression in SQC was analyzed in AE-meta and TCGA datasets, and further confirmed in lung cancer tissues and adjacent normal tissues with RT-qPCR and in-situ hybridization. Statistical analysis was performed to evaluate the clinical correlation between LINC00173.v1 expression and survival characteristics. A tube formation assay, chick embryo chorioallantoic membrane assay and animal experiments were conducted to detect the effect of LINC00173.v1 on the proliferation and migration of vascular endothelial cells and tumorigenesis of SQC in vivo. Bioinformatics analysis, RNA immunoprecipitation and luciferase reporter assays were performed to elucidate the downstream target of LINC00173.v1. The therapeutic efficacy of antisense oligonucleotide (ASO) against LINC00173.v1 was further investigated in vivo. Chromatin immunoprecipitation and high throughput data processing and visualization were performed to identify the cause of LINC00173.v1 overexpression in SQC. RESULTS: LINC00173.v1 was specifically upregulated in SQC tissues, which predicted poorer overall and progression-free survival in SQC patients. Overexpression of LINC00173.v1 promoted, while silencing LINC00173.v1 inhibited the proliferation and migration of vascular endothelial cells and the tumorigenesis of SQC cells in vitro and in vivo. Our results further revealed that LINC00173.v1 promoted the proliferation and migration of vascular endothelial cells and the tumorigenesis of SQC cells by upregulating VEGFA expression by sponging miR-511-5p. Importantly, inhibition of LINC00173.v1 via the ASO strategy reduced the tumor growth of SQC cells, and enhanced the therapeutic sensitivity of SQC cells to cisplatin in vivo. Moreover, our results showed that squamous cell carcinoma-specific factor ΔNp63α contributed to LINC00173.v1 overexpression in SQC. CONCLUSION: Our findings clarify the underlying mechanism by which LINC00173.v1 promotes the proliferation and migration of vascular endothelial cells and the tumorigenesis of SQC, demonstrating that LINC00173.v1-targeted drug in combination with cisplatin may serve as a rational regimen against SQC.

Downregulation of the circadian rhythm regulator HLF promotes multiple-organ distant metastases in non-small cell lung cancer through PPAR/NF-κb signaling.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death due to its early recurrence and widespread metastatic potential. Accumulating studies have reported that dysregulation of circadian rhythms-associated regulators is implicated in the recurrence and metastasis of NSCLC. Therefore, identification of metastasis-associated circadian rhythm genes is clinically necessary. Here we report that the circadian gene hepatic leukemia factor (HLF), which was dramatically reduced in early-relapsed NSCLC tissues, was significantly correlated with early progression and distant metastasis in NSCLC patients. Upregulating HLF inhibited, while silencing HLF promoted lung colonization, as well as metastasis of NSCLC cells to bone, liver and brain in vivo. Importantly, downexpression of HLF promoted anaerobic metabolism to support anchorage-independent growth of NSCLC cells under low nutritional condition by activating NF-κB/p65 signaling through disrupting translocation of PPARα and PPARγ. Further investigations revealed that both genetic deletion and methylation contribute to downexpression of HLF in NSCLC tissues. In conclusion, our results shed light on a plausible mechanism by which HLF inhibits distant metastasis in NSCLC, suggesting that HLF may serve as a novel target for clinical intervention in NSCLC.

MicroRNA-137-regulated AKT serine/threonine kinase 2 inhibits tumor growth and sensitizes cisplatin in patients with non-small cell lung cancer.

The present study investigated the role of microRNA-137-regulated AKT serine/threonine kinase 2 (AKT2) on tumor growth and cisplatin sensitivity in patients with non-small cell lung cancer (NSCLC). The results demonstrated that the expression of microRNA-137 in cisplatin-treated NSCLC patient tissue samples was markedly lower than that in healthy tissue samples. The disease-free survival and overall survival rates of patients with NSCLC exhibiting a high microRNA-137 expression were higher than the survival rates of patients with NSCLC exhibiting a low expression of microRNA-137. Overexpression of microRNA-137 inhibited the proliferation of A549 and H520 cells treated with cisplatin. Overexpression of miR-137 suppressed the protein expression of AKT2, increased caspase-3 activity, increased Bax protein expression and suppressed Cyclin D1 protein expression in A549 and H520 cells treated with cisplatin. MK2206, an AKT2 inhibitor, inhibited AKT2 protein expression and suppressed the proliferation of A549 and H520 cells treated with cisplatin following overexpression of miR-137. The inhibition of AKT2 also increased caspase-3 activity and Bax protein expression, and suppressed Cyclin D1 protein expression in A549 and H520 cells treated with cisplatin following overexpression of miR-137. Taken together, the results of the present study suggested that microRNA-137-regulated AKT2 inhibits tumor growth and sensitizes cisplatin in patients with NSCLC.

[Lymphatic metastasis intensity of and lymphadenectomy for thoracic esophageal squamous cell carcinoma].

BACKGROUND & OBJECTIVE: The intensity of lymphatic metastasis consists of lymph node metastasis number (LMN) and lymph node metastasis ratio (LMR). LMR is the ratio of positive nodes to dissected nodes. LMN and LMR are 2 important prognostic factors of esophageal cancer, and are adopted in tumor staging. This study was to assess the lymphatic metastasis intensity of thoracic esophageal squamous cell carcinoma (ESCC), and explore the influential factors and lymphadenectomy pattern. METHODS: A total of 120 patients with ESCC had been operated in the Second Affiliated Hospital of Sun Yat-sen University from 1998 to 2000. The lymph nodes were dissected according to the mapping scheme of the American Thoracic Society (ATS) modified by Casson et al. RESULTS: A total of 2 631 lymph nodes were dissected with an average of 22 lymph nodes in each case. The cervical LMR was significantly higher in the upper thoracic ESCC than in the middle and lower thoracic ESCC (20.9% vs. 12.9% and 6.8%, P<0.05). The left gastric LMR was significantly higher in the lower thoracic ESCC than in the middle and upper thoracic ESCC (37.5% vs. 17.5% and 7.1%, P<0.05). Subcarinal metastatic lymph nodes were often found in the middle thoracic ESCC. T stage, histological differentiation, and circum wall involvement degree were correlated to lymphatic metastasis intensity (P<0.05); the length of esophageal lesion had no correlation to lymphatic metastasis intensity (P>0.05). The survival time of the patients received the right thoracic esophagectomy with 3-field lymphadenectomy (3-FL) was significantly longer than that of the patients received the left thoracic esophagectomy with 2-FL (P<0.05). CONCLUSIONS: During the operation on ESCC, the regions with high lymphatic metastasis intensity should be dissected. T stage, histological differentiation, and circum wall involvement degree are important influential factors of lymphatic metastasis intensity. The right thoracic esophagectomy with 3-FL is superior to the left thoracic esophagectomy with 2-FL.