High PD-1 expression level is associated with an unfavorable prognosis in patients with cervical adenocarcinoma

Tumor immune escape: extracellular vesicles roles and therapeutics application

BACKGROUND

Immune escape, a process by which tumor cells evade immune surveillance, remains a challenge for cancer therapy. Tumor cells produce extracellular vesicles (EVs) that participate in immune escape by transferring bioactive molecules between cells. EVs refer to heterogeneous vesicles that participate in intercellular communication. EVs from tumor cells usually carry tumor antigens and have been considered a source of tumor antigens to induce anti-tumor immunity. However, evidence also suggests that these EVs can accelerate immune escape by carrying heat shock proteins (HSPs), programmed death-ligand 1 (PD-L1), etc. to immune cells, suppressing function and exhausting the immune cells pool. EVs are progressively being evaluated for therapeutic implementation in cancer therapies. EVs-based immunotherapies involve inhibiting EVs generation, using natural EVs, and harnessing engineering EVs. All approaches are associated with advantages and disadvantages. The EVs heterogeneity and diverse physicochemical properties are the main challenges to their clinical applications.

SHORT CONCLUSION

Although EVs are criminal; they can be useful for overcoming immune escape. This review discusses the latest knowledge on EVs population and sheds light on the function of tumor-derived EVs in immune escape. It also describes EVs-based immunotherapies with a focus on engineered EVs, followed by challenges that hinder the clinical translation of EVs that are essential to be addressed in future investigations. Video Abstract.

Immune checkpoints and cancer immunotherapies: insights into newly potential receptors and ligands

Checkpoint markers and immune checkpoint inhibitors have been increasingly identified and developed as potential immunotherapeutic targets in various human cancers. Despite valuable efforts to discover novel immune checkpoints and their ligands, the precise roles of their therapeutic functions, as well as the broad identification of their counterpart receptors, remain to be addressed. In this context, it has been suggested that various putative checkpoint receptors can be induced upon activation. In the tumor microenvironment, T cells, as crucial immune response against malignant diseases as well as other immune central effector cells, such as natural killer cells, are regulated via co-stimulatory or co-inhibitory signals from immune or tumor cells. Studies have shown that exposure of T cells to tumor antigens upregulates the expression of inhibitory checkpoint receptors, leading to T-cell dysfunction or exhaustion. Although targeting immune checkpoint regulators has shown relative clinical efficacy in some tumor types, most trials in the field of cancer immunotherapies have revealed unsatisfactory results due to de novo or adaptive resistance in cancer patients. To overcome these obstacles, combinational therapies with newly discovered inhibitory molecules or combined blockage of several checkpoints provide a rationale for further research. Moreover, precise identification of their receptors counterparts at crucial checkpoints is likely to promise effective therapies. In this review, we examine the prospects for the application of newly emerging checkpoints, such as T-cell immunoglobulin and mucin domain 3, lymphocyte activation gene-3, T-cell immunoreceptor with Ig and ITIM domains (TIGIT), V-domain Ig suppressor of T-cell activation (VISTA), new B7 family proteins, and B- and T-cell lymphocyte attenuator, in association with immunotherapy of malignancies. In addition, their clinical and biological significance is discussed, including their expression in various human cancers, along with their roles in T-cell-mediated immune responses.

Immunomodulatory Gene-Splicing Dysregulation in Tumorigenesis: Unmasking the Complexity

Cancer is a global health concern with rising incidence, morbidity, and mortality. The interaction between the tumor and immune cells within the tumor microenvironment is facilitated by signaling pathways driven by immunomodulatory proteins. Alternative splicing regulates the production of multiple immunomodulatory proteins with diverse functionality from a single mRNA transcript. Splicing factors are pivotal in modulating alternative splicing processes but are also subject to regulation. The dysregulation of alternative splicing may result from splicing factor (SF) abnormal expression levels and mutations in the cis and trans-acting elements and small nuclear RNA (snRNA) molecules. Aberrant splicing may generate abnormal mRNA transcripts encoding isoforms with altered functions that contribute to tumorigenesis or cancer progression. This review uncovers the complexity of immunomodulatory genes splicing dysregulation in oncogenesis. Identifying specific immunomodulatory splicing isoforms that contribute to cancer could be utilized to improve current immunotherapeutic drugs or develop novel therapeutic interventions for cancer.

T-cell activation is associated with high-grade serous ovarian cancer survival

AIM

High-grade serous ovarian cancer (HGSOC) is an aggressive disease that is largely resistant to today's immunotherapies. Here, we aimed to investigate the prognostic significance of CTLA4, PD-1, and T-cell activation status in HGSOC.

METHODS

Using a publicly accessed microarray dataset including 260 HGSOC samples, we calculated Kaplan-Meier survival curves for overall survival (OS), evaluated associations with multivariate Cox regression models to evaluate the associations, and summarized using a hazard ratio (HR). The correlations between PD-1 gene expression and that of other genes were calculated by Pearson correlation.

RESULTS

Multivariate survival analyses showed that high PD-1 expression but not CTLA4 was associated with longer OS (HR = 0.69; 95% confidence interval [CI] = 0.52-0.91; p = 0.01), and that higher T-cell activation score was associated with better outcome (HR = 0.74; 95% confidence interval [CI] = 0.58-0.95; p = 0.02). The top three PD-1 highly correlated genes were SIRPG (r = 0.90, p < 2E-16), FASL (r = 0.89, p < 2E-16), and CD8a (r = 0.87, p < 2E-16). HGSOC patients' OS is positively associated T-cell activation score and PD-1 expression but not CTLA4.

CONCLUSION

T cell activation score may serve as a candidate for personalized immunotherapy in HGSOC. The application of anti-PD-1 therapy to HGSOC should be cautious.

PD-L1: Can it be a biomarker for the prognosis or a promising therapeutic target in cervical cancer?

Cervical cancer is one of the most common in the female genital tract and remains a leading cause that threatens the health and lives of women worldwide, although preventive vaccines and early diagnosis have reduced mortality. While treatment by operation and chemoradiotherapy for early-stage patients achieve good outcomes, the great majority of cervical cancers caused by the human papilloma virus (HPV) make immunotherapy realizable for patients with advanced and recurrent cervical cancer. To date, some clinical trials of checkpoint immunotherapy in cervical cancer have indicated significant benefits of programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) inhibitors, providing strong evidence for PD-1/PD-L1 as a therapeutic target. In this review article, we discuss the role of PD-L1 and the application of PD-L1 inhibitors in cervical cancer, with the aim of providing direction for future research.

P16INK4A expression might be associated with a favorable prognosis for cervical adenocarcinoma via dysregulation of the RB pathway

Previous studies have largely failed to clarify the relationship between p16^INK4A status and cervical adenocarcinoma prognosis. The current study aimed to examine the clinical and pathological significance of p16^INK4A expression in several cervical adenocarcinoma subtypes. Eighty-two samples collected from patients with cervical adenocarcinoma were formalin fixed and paraffin embedded. Next, p16^INK4A levels were analyzed with immunohistochemistry. Additionally, the relationship between p16^INK4A expression and clinicopathological factors as well as prognosis was evaluated. The expression of p16^INK4A was mostly detected in all usual cervical adenocarcinoma subtypes. In the gastric type, only a few cases were positive for p16^INK4A expression. Results of the Kaplan–Meier analysis indicated that the positive p16^INK4A expression in tumor cells was significantly associated with favorable progression-free survival and overall survival in patients with cervical adenocarcinoma (p = 0.018 and p = 0.047, respectively, log-rank test). Our findings suggest that the status of p16^INK4A expression may influence prognosis. Thus, p16^INK4A expression could be used as a biomarker for improving the prognosis of patients with cervical adenocarcinoma.

PD-L1 expression and immune stromal features in HPV-independent cervical adenocarcinoma

AIMS

Human papilloma virus (HPV)-independent cervical adenocarcinoma (CA) is usually diagnosed at an advanced stage, while the therapeutic options are limited. Therefore, effective treatment options are required. The programmed cell death 1 (PD-1) inhibitor pembrolizumab has been approved for the treatment of patients with recurrent or metastatic cervical squamous cell carcinoma expressing PD-ligand 1 (PD-L1). However, no data regarding PD-L1 expression in HPV-independent CA are available. Thus, we evaluated the association between PD-L1 expression and the clinicopathological characteristics and survival of patients with HPV-independent CA.

METHODS

We evaluated PD-L1, mismatch repair (MMR) protein expression and the immune stromal features of 44 patients with HPV-independent CA. PD-L1 expression was defined as a combined positive score (CPS) ≥1 and a tumour proportion score (TPS) ≥1%.

RESULTS

PD-L1 expression was observed in 14 cases (31.8%) with CPS ≥1 and 12 cases (27.3%) with TPS ≥1%. PD-L1 expression, based on either the CPS or the TPS, was associated with a high tumour-infiltrating lymphocyte percentage (CPS = P < 0.001; TPS = P < 0.001). Patients with a PD-L1 CPS ≥1 showed worse progression-free survival and overall survival than PD-L1-negative patients (P = 0.004 and P = 0.023, respectively). Forty-two cases demonstrated intact MMR expression and two cases demonstrated loss of MSH2/MSH6.

CONCLUSIONS

Our data demonstrated that PD-L1 was expressed in HPV-independent CA, especially in clear cell carcinoma, and that PD-L1 expression is a negative prognostic marker. Our data support the role of PD-L1 in HPV-independent CA and its potential as an immunotherapeutic target.

Whole-Exome Sequencing of Rare Site Endometriosis-Associated Cancer

Malignant transformation of extraovarian endometriosis is rare, with the carcinogenesis mechanism unclear. To clarify the actionable variants of rare-site endometriosis-associated cancer (RSEAC), we performed whole-exome sequencing for the tumor, in two patients. The intestine was affected in both cases, although the histology was that of clear cell carcinoma and undifferentiated carcinoma, respectively. Therefore, the cases were referred to as endometriosis-associated intestinal tumors (EIATs). Actionable variants (all frameshift mutations) were identified in tumor suppressor genes ARID1A, PTEN, and p53; however, no oncogenic variants were identified. Both cases were microsatellite stable. The patient with undifferentiated carcinoma exhibited hypermutator and homologous recombination deficiency phenotypes. The dominant mutation signatures were signature 30 (small subset of breast cancers) and 19 (pilocytic astrocytoma) in patient 1, and signature 5 (small subset of breast cancers) and 3 (breast, ovarian, and pancreatic cancers) in patient 2. Immunohistochemistry revealed positive CD8 and PD-1 expression in both patients; patient 1 also showed positive PDL-1 expression. Our results suggest that RSEAC is associated with variants of tumor suppressor genes as epigenetic alterations. Mutation signature-based whole-exome sequencing could be useful to select an adjuvant chemotherapy regimen. High CD8 and PD-1 expression in RSEAC suggests that immune checkpoint inhibitors are useful for treatment.

Skin immunization for effective treatment of multifocal melanoma refractory to PD1 blockade and Braf inhibitors

BACKGROUND

Despite the remarkable benefits associated with the interventional treatment of melanomas (and other solid cancers) with immune checkpoint and Braf inhibitors (Brafi), most patients ultimately progress on therapy. The presence of multifocal/disseminated disease in patients increases their mortality risk. Hence, the development of novel strategies to effectively treat patients with melanomas that are resistant to anti-PD1 mAb (αPD1) and/or Brafi, particularly those with multifocal/disseminated disease remains a major unmet clinical need.

METHODS

Mice developing induced/spontaneous BrafV600E/Pten-/- melanomas were treated by cutaneous immunization with a DNA vaccine encoding the melanoma-associated antigen TRP2, with Brafi or αPD1 alone, or with a combination of these treatments. Tumor progression, tumor-infiltration by CD4+ and CD8+ T cells, and the development of TRP2-specific CD8+ T cells were then monitored over time.

RESULTS

Vaccination led to durable antitumor immunity against PD1/Brafi-resistant melanomas in both single lesion and multifocal disease models, and it sensitized PD1-resistant melanomas to salvage therapy with αPD1. The therapeutic efficacy of the vaccine was associated with host skin-resident cells, the induction of a systemic, broadly reactive IFNγ+CD8+ T cell repertoire, increased frequencies of CD8+ TIL and reduced levels of PD1hi/intCD8+ T cells. Extended survival was associated with improved TIL functionality, exemplified by the presence of enhanced levels of IFNγ+CD8+ TIL and IL2+CD4+ TIL.

CONCLUSIONS

These data support the use of a novel genetic vaccine for the effective treatment of localized or multifocal melanoma refractory to conventional αPD1-based and/or Brafi-based (immune)therapy.

Prognostic Implications of Immune-Related Genes' (IRGs) Signature Models in Cervical Cancer and Endometrial Cancer

Cervical cancer and endometrial cancer remain serious threats to women's health. Even though some patients can be treated with surgery plus chemoradiotherapy as a conventional option, the overall efficacy is deemed unsatisfactory. As such, the development for new treatment approaches is truly necessary. In recent years, immunotherapy has been widely used in clinical practice and it is an area of great interest that researchers are keeping attention on. However, a thorough immune-related genes (IRGs) study for cervical cancer and endometrial cancer is still lacking. We therefore aim to make a comprehensive evaluation of IRGs through bioinformatics and large databases, and also investigate the relationship between the two types of cancer. We reviewed the transcriptome RNAs of IRGs and clinical data based on the TCGA database. Survival-associated IRGs in cervical/endometrial cancer were identified using univariable and multivariable Cox proportional-hazard regression analysis for developing an IRG signature model to evaluate the risk of patients. In the end, this model was validated based on the enrichment analyses through GO, KEGG, and GSEA pathways, Kaplan-Meier survival curve, ROC curves, and immune cell infiltration. Our results showed that out of 25/23 survival-associated IRGs for cervical/endometrial cancer, 13/12 warranted further examination by multivariate Cox proportional-hazard regression analysis and were selected to develop an IRGs signature model. As a result, enrichment analyses for high-risk groups indicated main enriched pathways were associated with tumor development and progression, and statistical differences were found between high-risk and low-risk groups as shown by Kaplan-Meier survival curve. This model could be used as an independent measure for risk assessment and was considered relevant to immune cell infiltration, but it had nothing to do with clinicopathological characteristics. In summary, based on comprehensive analysis, we obtained the IRGs signature model in cervical cancer (LTA, TFRC, TYK2, DLL4, CSK, JUND, NFATC4, SBDS, FLT1, IL17RD, IL3RA, SDC1, PLAU) and endometrial cancer (LTA, PSMC4, KAL1, TNF, SBDS, HDGF, LTB, HTR3E, NR2F1, NR3C1, PGR, CBLC), which can effectively evaluate the prognosis and risk of patients and provide justification in immunology for further researches.