The efficacy of cancer immunotherapy largely depends on the tumor microenvironment, especially the tumor immune microenvironment. Emerging studies have claimed that microbes reside within tumor cells and immune cells, suggesting that these microbes can impact the state of the tumor immune microenvironment. For the first time, this review delineates the landscape of intra-tumoral microbes and their products, herein defined as the tumor microbe microenvironment. The role of the tumor microbe microenvironment in the tumor immune microenvironment is multifaceted: either as an immune activator, inhibitor, or bystander. The underlying mechanisms include: (I) the presentation of microbial antigens by cancer cells and immune cells, (II) microbial antigens mimicry shared with tumor antigens, (III) microbe-induced immunogenic cell death, (IV) microbial adjuvanticity mediated by pattern recognition receptors, (V) microbe-derived metabolites, and (VI) microbial stimulation of inhibitory checkpoints. The review further suggests the use of potential modulation strategies of the tumor microbe microenvironment to enhance the efficacy and reduce the adverse effects of checkpoint inhibitors. Lastly, the review highlights some critical questions awaiting to be answered in this field and provides possible solutions. Overall, the tumor microbe microenvironment modulates the tumor immune microenvironment, making it a potential target for improving immunotherapy. It is a novel field facing major challenges and deserves further exploration.

These results reveal the feasible functions of lncRNAs in pathogenesis of MM. Further studies are required to explore whether these lncRNAs could serve as candidate therapeutic targets and new molecular biomarkers for MM.

Proteasome inhibitor bortezomib is one of the most effective drugs currently available for the treatment of multiple myeloma (MM). However, the intrinsic and acquired resistance to bortezomib can limit its effectiveness. The activation of heat shock response has been characterized as a potential resistance mechanism protecting MM cells from bortezomib-induced cell death. In this study, in response to bortezomib therapy, we discovered that HSP70 is one of the most substantially upregulated heat shock proteins. In order to further explore approaches to sensitizing bortezomib-based treatment for MM, we investigated whether targeting HSP70 using a specific inhibitor VER-155008 combined with bortezomib could overcome the acquired resistance in MM. We found that HSP70 inhibitor VER-155008 alone significantly decreased MM cell viability. Moreover, the combination of VER-155008 and bortezomib synergistically induced MM cell apoptosis markedly in vitro. Notably, the combined treatment was found to increase the cleavage of PARP, an early marker of chemotherapy-induced apoptosis. Importantly, the reduction of anti-apoptotic Bcl-2 family member Bcl-2, Bcl-xL, and Mcl-1 and the induction of pro-apoptotic Bcl-2 family member BH3-only protein NOXA and Bim were confirmed to be tightly associated with the synergism. Finally, the ER stress marker CHOP (CCAAT-enhancer binding protein homologous protein), which can cause transcriptional activation of genes involved in cell apoptosis, was markedly induced by both VER-155008 and bortezomib. Taken together, our finding of a strong synergistic interaction between VER-155008 and bortezomib may support for combination therapy in MM patients in the future.

Background: The aim of this study was to detect the expression of long noncoding RNA small nucleolar RNA host gene 18 (SNHG18) andsemaphorin 5A (SEMA5A) genes in multiple myeloma (MM) patients and to explore the correlation of the expression of these genes with the clinical characteristics and prognosis of MM patients. Methods: Forty-seven newly diagnosed MM, 18 complete remission MM, 13 refractory/relapse MM, and 22 iron deficiency anemia (serving as control) samples were extracted at the Department of Hematology, Second Affiliated Hospital of Xian Jiaotong University between January 2015 and December 2016. The clinical features of the MM patients are summarized. Real-time quantitative PCR was performed to analyze the relative expression levels of the SNHG18 and SEMA5Agenes. The clinical characteristics and overall survival (OS) of the MM patients were statistically analyzed while measuring different levels of SNHG18 and SEMA5Agene expression. At the same time, the correlation between the expression of SNHG18 and SEMA5A was also analyzed. Results: The analysis confirmed that SNHG18 and its possible target gene SEMA5A were both highly expressed in newly diagnosed MM patients. After analyzing the clinical significance of SNHG18 and SEMA5A in MM patients, we found that the expression of SNHG18 and SEMA5A was related to the Durie-Salmon (DS), International Staging System (ISS), and Revised International Staging System (R-ISS) classification systems, and the Mayo Clinic Risk Stratification for Multiple Myeloma (mSMART; p < 0.05). Moreover, we observed a significant difference in OS between the SNHG18/SEMA5A high expression group and the low expression group. We found a positive correlation between SNHG18 and SEMA5A expression (r = 0.709, p < 0.01). Surprisingly, the expected median OS times of both the SNHG18 and SEMA5Ahigh expression groups were significantly decreased, which was in contrast to those of both the SNHG18 and SEMA5Alow expression groups and the single-gene high expression group (p < 0.05). Conclusion: High expression of both SNHG18 and SEMA5A is associated with poor prognosis in patients with MM.

Rationale:The recurrence of cutaneous squamous cell carcinoma (cSCC) after surgery is associated with the reprogramming of the tumor microenvironment (TME), and remains a key factor affecting its outcomes. Methods: We employed single-cell RNA sequencing (scRNA-seq) to examine the dynamic changes in epithelial cells, T cells, myeloid cells, and fibroblasts between primary and recurrent cSCC. Cell clustering, cell trajectory, cell-cell communication, and gene set enrichment analysis were used to investigate the TME heterogeneity between primary and recurrent cSCC. Gene expression differences were monitored by IHC staining. Results: We examined the immunosuppressed microenvironment in recurrent cSCC, which exhibited a T cell-excluded and SPP1 + tumor-associated macrophages (TAMs)-enriched status. In recurrent cSCC, CD8 + T cells showed high exhaustion and low inflammatory features, while SPP1 + TAMs displayed global pro-tumor characteristics, including decreased phagocytosis and inflammation and increased angiogenesis. Furthermore, the subgroups of SPP1 + TAMs harbored distinct functions. SPP1 + CD209 high TAMs showed features of phagocytosis, while SPP1 + CD209 low TAMs tended to have a high angiogenic ability. A subpopulation of tumor-specific keratinocytes (TSKs) showed significant epithelial-mesenchymal transition (EMT) features in recurrent cSCC, probably due to their active communication with IL7R + cancer-associated fibroblasts (CAFs). Moreover, we found that the pleiotropic growth factor/cytokine Midkine (MDK) could provoke different cell-cell interactions in cSCC with distinctive staging. In primary cSCC, MDK was highly expressed in fibroblasts and could promote their proliferation and block the migration of tumor cells, while in recurrent cSCC, the high expression of MDK in TSKs promoted their proliferation and metastasis. Conclusion:Our study provides insights into the critical mechanisms of cSCC progression, which might facilitate the development of a powerful approach for the prevention and treatment of cSCC recurrence.

Objective: Frequent loss of expression of platelet factor 4 (PF4) in multiple myeloma (MM) was revealed in several previous researches. The predictive analysis of serum PF4 level in newly diagnosed MM has not been well elucidated. This study is to assess if serum PF4 could be a prognostic factor in predicting treatment response and survival of MM treated with thalidomide and VAD regimens. Methods: Sera of 122 MM were gained pre-and post-treatment of chemotherapy and oral thalidomide. Serological PF4 measurements were performed by ELISA. Kaplan-Meier method was employed for survival analysis. Log rank test was used significance analysis. Multivariate analysis of overall survival used Cox-regression. Results: Our data showed that the median serum PF4 concentration was negatively associated with MM response and a significant correlation between serum PF4 level and unfavorable clinical features (β2-microglobulin, ISS stage, del17p and creatinine). MM with lower serum PF4 concentration at diagnosis were prone to gain complete remission and very good partial remission after two courses of chemotherapy. Besides del17p, β2-microglobulin, treatment response, the low serum PF4 concentration was an independent variable associated with a poor overall survival by univariate analysis and multivariate analysis. Conclusions: We speculate serum PF4 is a promising response and prognostic factor in newly diagnosed MM treated with thalidomide and VAD regimens.

No abstract

Background. Both the tumor environment and the genomic landscape of lung cancer may shape patient responses to treatments, including immunotherapy, but their joint impacts on lung adenocarcinoma (LUAD) prognosis are underexplored. Methods. RNA sequencing data and whole-exome sequencing results were downloaded from the TCGA database, and only LUAD-related data were included in this study. Based on gene expression data, the ESTIMATE algorithm was used to estimate stromal and immune scores, and CIBERSORT analysis was used for quantification of the relative abundances of immune cells. Somatic mutations were used for calculating tumor mutation burden (TMB). Specific mutations in genes involved in DNA damage repair (DDR) pathways were identified. The individual and joint associations of stromal and immune score, TMB, and DDR gene mutations with 5-year survival were analyzed by the Kaplan–Meier method and multivariate Cox model. Results. LUAD patients with a high (>highest 25%) stromal or immune score had prolonged survival as compared to those with a low (<lowest 25%) score (log-rank P = 0.05 and 0.035, respectively). Patients with both high stromal and immune scores had the most favorable survival. Although the survival differences between patients with high (>highest 25%) and low (<lowest 25%) TMB, or between patients with mutant- and wild-type DDR genes were not statistically significant, a survival benefit from high TMB or DDR gene mutations was observed in patients with high stromal or immune scores. Conclusion. A comprehensive evaluation of transcriptomic signatures and genomic biomarkers may provide a novel avenue for improving prognosis stratification in LUAD.