Biomarkers to predict prognosis and response to checkpoint inhibitors

Cancer Immunotherapy

The enhanced understanding of immunology experienced over the last 5 decades afforded through the tools of molecular biology has recently translated into cancer immunotherapy becoming one of the most exciting and rapidly expanding fields. Human cancer immunotherapy is now recognized as one of the pillars of treatment alongside surgery, radiation, and chemotherapy. The field of veterinary cancer immunotherapy has also rapidly advanced in the last decade with a handful of commercially available products and a plethora of investigational cancer immunotherapies, which will hopefully expand our veterinary oncology treatment toolkit over time.

The combination of circulating IgM and geriatric nutritional risk index predicts the prognostic of hepatocellular carcinoma patients who underwent immune checkpoint inhibitors

OBJECTIVE

Immune checkpoint inhibitors (ICIs) have shown promise in hepatocellular carcinoma (HCC) treatment. With the increasing use of ICIs in cancer treatment, identifying biomarkers that can predict the prognosis of patients receiving ICIs is of great importance. We aimed to investigate the potential of circulating immunoglobulins and the combination of Geriatric Nutritional Risk Index (GNRI) with IgM to predict prognosis in patients with HCC who received ICIs.

METHODS

Clinical and pathological data were collected from 101 patients with HCC who were administered ICIs and underwent circulating immunoglobulin testing between January 2018 and December 2021. Survival analysis, Cox regression analysis, and nomogram construction were performed to evaluate the prognostic value of the indicators.

RESULTS

In the preliminary survival analysis, we observed a significant correlation between patient prognosis and IgM levels. Patients with low IgM had shorter survival times. Upon combining the GNRI with IgM, patients with low GNRI and IgM levels had shorter progression-free survival (PFS) and overall survival (OS) (P < 0.001). Additionally, GNRI-IgM had the highest area under the curve (AUC) and was identified as an independent prognostic marker in this study. The C-indices of the nomograms for PFS and OS were 0.797 (0.734-0.860) and 0.827 (0.778-0.876), respectively.

CONCLUSIONS

IgM was significantly associated with the prognosis of patients with HCC receiving ICIs. The combination of the GNRI with IgM provided superior prognostic value and served as an independent prognostic marker. The GNRI-IgM can be used to effectively identify patients with HCC who are responsive to ICIs.

Treatment of metastatic alveolar soft part sarcoma with axitinib and pembrolizumab in an 80-year-old patient with a history of autoimmune disorders

Alveolar soft part sarcoma (ASPS) is a rare malignancy with low sensitivity to chemotherapy. While localized ASPS has a very good prognosis after resection, the 5-year overall survival rate drops substantially in metastatic disease. We report the case of an 80-year-old male patient with ASPS of the left elbow and metastasis to the lung, lymph nodes and peritoneum. After weighing the benefits and risks, systemic treatment with the anti-PD-1 checkpoint inhibitor pembrolizumab combined with the vascular endothelial growth factor receptor tyrosinkinase inhibitor axitinib was initiated in this patient with a history of psoriasis and Crohn's disease. After only two cycles of therapy, a significant size reduction of the nodal cervical metastasis became apparent. A partial response of all metastases was then confirmed in the first computed tomography restaging. So far, side effects have remained manageable, especially with regard to the development or worsening of autoimmune adverse events. The patient continued to have a high quality of life, while also remaining in ongoing partial response for 15 months at the time of submission. While sarcomas generally have low sensitivity to immunotherapies, ASPS is an exception, and checkpoint inhibition is an integral part of its systemic therapy.

Severe Immune-Related Adverse Events in Patients Treated with Nivolumab for Metastatic Renal Cell Carcinoma Are Associated with PDCD1 Polymorphism

Single nucleotide polymorphisms (SNPs) reportedly influence the effect of nivolumab in metastatic renal cell carcinoma (mRCC). This study aimed to evaluate the relationship between the clinical outcomes of patients with mRCC and SNPs in programmed cell death protein 1 (PD-1) protein-coding gene (PDCD1) and explore any potential correlation with patient prognosis and incidence of immune-related adverse events (irAEs). In total, 106 patients with mRCC, who were treated with nivolumab alone (n = 59) or nivolumab and ipilimumab (n = 47), were enrolled in the study. Three SNPs in the PDCD1 gene, namely PD-1.3, PD-1.5, and PD-1.6, were assessed. Patients harboring the PD-1.6 G allele experienced more severe (odds ratio, 3.390; 95% confidence interval 1.517–7.756; p = 0.003) and multiple (OR, 2.778; 95% CI, 1.020–6.993 p = 0.031) irAEs than those harboring the AA genotype. Thus, the existence of the PDCD1 PD-1.6 polymorphism (G allele) was associated with the occurrence of severe and multiple irAEs in patients with mRCC. Further evaluation of PDCD1 polymorphisms might help identify patients experiencing irAE by nivolumab treatment.

Overexpressed VDAC1 in breast cancer as a novel prognostic biomarker and correlates with immune infiltrates

BACKGROUND

More and more evidence suggests that cancer is a mitochondrial metabolic disease recently and mitochondria dysfunction is critical to tumorigenesis. As a gatekeeper of mitochondria, the voltage-dependent anion channel 1 (VDAC1) is associated with the development of breast cancer (BC). However, its potential mechanism and clinical significance remain unclear; thus, in this research, we aimed to explore it.

METHODS

VDAC1 expression in BC tissues and normal tissues was obtained from The Cancer Genome Atlas (TCGA) and validated by datasets from the gene expression omnibus (GEO) database. Then, the relationships between VDAC1 expression and clinicopathological features were analyzed. Receiver operating characteristics (ROC) curves were used to identify the diagnostic value of VDAC1. The prognostic value was evaluated by Kaplan-Meier survival curves and Cox regression analysis. VDAC1 with its co-expression genes were subjected to enrichment analysis to explore potential mechanisms in BC and the protein-protein interaction (PPI) network was constructed. At last, the association between VDAC1 expression and infiltration levels of immune cell infiltration by various methods, as well as their corresponding markers, was analyzed. We also analyzed the correction between VDAC1 expression and eight immune checkpoint genes and the tumor immune dysfunction and exclusion (TIDE) scores of each BC sample in TCGA were calculated and the differences between high and low VDAC1 expression groups were analyzed.

RESULTS

VDAC1 expression was remarkably elevated in BC (p < 0.001), and high expression of VDAC1 was associated with the positive expression of ER (p = 0.004), PR (p = 0.033), and HER2 (p = 0.001). ROC analysis suggested that VDAC1 had diagnosed value in BC. The Kaplan-Meier analysis suggested that higher expression of VDAC1 was associated with shorter overall survival (OS), and further Cox regression analysis revealed that VDAC1 was an independent factor of unfavorable prognosis in BC patients. Enrichment analysis of VDAC1 and its co-expression suggested that VDAC1 was related to the regulation of mitochondrial energy metabolism and protein modification, and the HIF-1 singing pathway might be the potential mechanism in BC. Notably, we found that VDAC1 expression was infiltration levels of most types of immune cells, as well as the expression of marker genes of immune cells. The ICGs PDCD1, CTLA4, LAG3, SIGLEC15, and TIGIT were negatively corrected with VDAC1 expression in BC. TIDE scores between the low and high expression groups showed no difference.

CONCLUSION

Overexpressed VDAC1 in BC could be severed as a novel biomarker for diagnosis and VDAC1 was an independent factor for adverse prognosis prediction. Our study revealed that VDAC1 might inhibit tumor immunity and might be a novel therapeutic target in BC.

Tumor shrinkage patterns of nivolumab monotherapy in metastatic renal cell carcinoma

OBJECTIVES

To investigate the tumor shrinkage patterns of patients with metastatic renal cell carcinoma treated with nivolumab monotherapy.

METHODS

Forty-four consecutive patients with metastatic renal cell carcinoma treated with nivolumab monotherapy (81 metastatic and four primary lesions) between September 2013 and December 2020 were retrospectively analyzed. The tumor shrinkage rate of individual visceral and lymph node metastatic lesions and the primary site lesions treated with nivolumab monotherapy, as well as the association between overall survival and pretreatment tumor size, were statistically assessed.

RESULTS

Pretreatment tumor size for the total and individual target lesions, which included kidneys, lungs, pancreas, and lymph nodes, were not correlated with tumor shrinkage rate. The tumor shrinkage rate was found to have no significant association with pretreatment tumor size between any organ. In addition, there is no significant difference in tumor shrinkage rate between larger (>median value) and smaller (<median value) pretreatment tumor size in any organ. Finally, there was no significant difference in overall survival between larger and smaller pretreatment tumor size.

CONCLUSIONS

Pretreatment tumor size was not associated with the tumor shrinkage rate and overall survival in nivolumab monotherapy.

SLC1A5 Prefers to Play as an Accomplice Rather Than an Opponent in Pancreatic Adenocarcinoma

Background: SLC1A5, a ferroptosis regulator gene, plays a dual role in cancer regulation. However, the roles of SLC1A5 in pancreatic adenocarcinoma (PAAD) remain elusive.

Methods: SLC1A5’s expression and somatic mutation information were determined by TCGA, GEO, Oncomine, and cBioPortal databases. Its prognostic value was assessed in TCGA cohort and was validated in three independent cohorts. The effects of SLC1A5 on the tumor immune microenvironment were analyzed by the CIBERSORT algorithm, ssGSEA method, and TISIDB and TIMER databases. The “oncoPredict” R package, TIDE algorithm, ImmuCellAI online tool, and GSE35141 and GSE59357 datasets were used to ascertain its therapeutic correlations. GSEA and Western blot were applied to reveal the effects of SLC1A5 on the mTORC1 signaling pathway and ferroptosis process. The biofunctions of SLC1A5 were assessed by MTT, wound-healing, Transwell, and xenograft assays.

Results: SLC1A5 was significantly upregulated in the PAAD samples but was not commonly accompanied with somatic mutation (2.3%). Overexpression of SLC1A5 led to a poor prognosis and was identified as an independent prognostic factor. Moreover, high SLC1A5 expression suppressed the antitumor immune process by changing the infiltrating levels of immune cells. As for therapeutic correlations, SLC1A5 was related to the efficacy of dasatinib, sunitinib, sorafenib, and imatinib but may not predict that of radiotherapy, chemotherapeutic drugs, and immune checkpoints inhibitors (ICIs). Notably, the overexpression of SLC1A5 could activate the mTORC1 signaling pathway and may increase the cellular sensitivity to ferroptosis. Finally, the overexpression of SLC1A5 markedly promoted proliferation, migration, and invasion of pancreatic cancer cells. At the in vivo level, SLC1A5 deletion inhibited tumor growth in a mice xenograft model.

Conclusions: SLC1A5 prefers to play as an accomplice rather than an opponent in PAAD. Our findings provide novel insights into PAAD treatment.

Recent Advances in Medical Therapy for Urological Cancers

The mainstay of medical treatment has been tyrosine kinase inhibitors (TKIs) for renal cell cancer (RCC), cytotoxic chemotherapy for urothelial cancer (UC), and androgen deprivation therapy for prostate cancer. These therapeutic modalities still play important roles in these malignancies. However, immune checkpoint inhibitors (ICIs) that target PD-1/PD-L1 or CTLA-4 are being rapidly introduced for the treatment of metastatic urological cancers, just as they have been for other malignancies. Currently, the paradigm of medical treatment for patients with metastatic urological cancer is dramatically changing. Accordingly, we need to organize and summarize the new therapeutic tools, which include immune checkpoint inhibitors, poly (ADP-ribose) polymerase (PARP) inhibitors, and antibody-drug conjugates (ADCs). This review provides an overview of agents and regimens that have just launched or will be launched in the near future in Japan. Based on the promising anti-tumor efficacy and manageable safety profiles being demonstrated in clinical trials, these new agents and therapies are expected to be rapidly introduced in Japanese clinical practice. Additionally, the newly designed ADC, enfortumab vedotin, which comprises a fully human monoclonal antibody conjugated to an anti-cancerous agent via a protease-cleavable linker, has just been launched in Japan. In order to provide the optimal treatment for our patients, we need to completely understand these new therapeutic tools.

Impact of Body Mass Index on Survival Outcomes of Patients with Metastatic Renal Cell Carcinoma in the Immuno-oncology Era: A Systematic Review and Meta-analysis

Context

Body mass index (BMI) is a useful tool for measuring body composition. It is unclear whether high BMI is a favourable indicator in patients with metastatic renal cell carcinoma (mRCC) treated with immune checkpoint inhibitors (ICIs).

Objective

To investigate the prognostic significance of BMI in patients with mRCC treated with ICIs in a systematic review and meta-analysis.

Evidence acquisition

Ovid MEDLINE, Embase, and Web of Science were systematically searched in July 2021, and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

Evidence synthesis

A total of 517 nonduplicate citations were screened by title and abstract, followed by full-text screening of 57 candidate articles to determine whether each study met the eligibility criteria. Overall, a total of 2281 patients from eight studies were included in the systematic review and meta-analysis. BMI levels were compared with overall survival (OS) and progression-free survival (PFS) in seven and three studies, respectively. Overweight/obese BMI was significantly associated with better OS compared to normal BMI (adjusted hazard ratio [aHR] 0.77, 95% confidence intervals [CI] 0.65-0.91; p = 0.002). A similar trend was observed for PFS (aHR 0.66, 95% CI 0.44-1.00; p = 0.050). There was no statistical heterogeneity or obvious publication bias among these studies.

Conclusions

This is the first systematic review and meta-analysis to evaluate the impact of BMI on survival outcomes of patients with mRCC treated with ICIs. To confirm the existence of the obesity paradox for patients with mRCC in the immuno-oncology era, high-quality clinical trials and basic research are warranted.

Patient summary

We reviewed published data on survival outcomes of 2281 patients with metastatic kidney cancer treated with immunotherapy drugs in relation to their body mass index (BMI). We found that higher BMI was associated with better survival when compared to normal BMI for this disease setting and treatment strategy.

Soluble forms of PD-1/PD-L immune checkpoint receptor and ligand in blood serum of breast cancer patients: association with clinical pathologic factors and molecular type of the tumor

Results of enzyme-linked immunosorbent assay of the soluble forms of PD-1/PD-L immune checkpoint receptor and ligand (sPD-1 and sPD-L1) in pretreatment blood serum of 88 breast cancer patients at various disease stages aged 30-83 years are presented. The control group included 55 practically healthy women aged 19-82 years. Serum sPD-1 and sPD-L1 levels in breast cancer patients highly significantly (p<0.0001) differ from control and these changes are opposite: soluble receptor level is more than 6-fold decreased, while soluble ligand concentration - 5.5 fold increased. Both markers separately, as well as their ratio demonstrate very high sensitivity (94-100%) and specificity (95-100%) in relation to healthy control. No statistically significant associations of sPD-1 and sPD-L1 levels with clinical stage, individual TNM system criteria, tumor histological structure, grade, receptor status, and molecular type were established. In particular, no significant peculiarities of the markers' levels in triple negative breast cancer successfully treated with anti-PD-1/PD-L1 preparations were revealed. Long-term follow-up and dynamic studies of sPD-1 and sPD-L1serum levels in the course of treatment are required for evaluation of their independent from clinical and morphological factors prognostic significance and the possibility of application as low invasive tests for prediction and monitoring of corresponding targeted therapy efficiency.

Improvement of Medical Treatment in Japanese Patients With Metastatic Renal Cell Carcinoma

BACKGROUND/AIM

To evaluate the relationship between treatment period and overall survival (OS) and to identify clinical factors associated with OS in patients with metastatic renal cell carcinoma (mRCC).

PATIENTS AND METHODS

Two hundred thirteen consecutive patients with mRCC receiving systemic therapy between 2008 and 2020 were divided into two groups: those starting first-line therapy in 2008-2015 (n=133) and those in 2016-2020 (n=80). Clinical factors associated with OS were retrospectively and statistically analyzed.

RESULTS

Median OS and one-, three- and five-year OS rates were not reached and 88.7%, 64.9%, and 64.9% in patients treated in 2016-2020; 31.4 months and 78.5%, 42.8% and 34.2% in 2008-2015 (p=0.0013). Multivariate analysis identified the period in which first-line therapy was started as the strongest predictor for OS (p=0.0002).

CONCLUSION

OS was significantly better in mRCC patients treated in 2016-2020 than in 2008-2015. Treatment period was the strongest predictor for OS.

Immuno-transcriptomic profiling of extracranial pediatric solid malignancies

We perform an immunogenomics analysis utilizing whole-transcriptome sequencing of 657 pediatric extracranial solid cancer samples representing 14 diagnoses, and additionally utilize transcriptomes of 131 pediatric cancer cell lines and 147 normal tissue samples for comparison. We describe patterns of infiltrating immune cells, T cell receptor (TCR) clonal expansion, and translationally relevant immune checkpoints. We find that tumor-infiltrating lymphocytes and TCR counts vary widely across cancer types and within each diagnosis, and notably are significantly predictive of survival in osteosarcoma patients. We identify potential cancer-specific immunotherapeutic targets for adoptive cell therapies including cell-surface proteins, tumor germline antigens, and lineage-specific transcription factors. Using an orthogonal immunopeptidomics approach, we find several potential immunotherapeutic targets in osteosarcoma and Ewing sarcoma and validated PRAME as a bona fide multi-pediatric cancer target. Importantly, this work provides a critical framework for immune targeting of extracranial solid tumors using parallel immuno-transcriptomic and -peptidomic approaches.

The roles of ferroptosis regulatory gene SLC7A11 in renal cell carcinoma: A multi-omics study

Background

The ferroptosis inhibitory gene Solute carrier family 7 member 11 (SLC7A11) provides a new strategy for anticancer treatment. However, its function in renal cell carcinoma (RCC) remains elusive.

Methods

The expression and somatic mutation information of SLC7A11 in RCC samples were determined using The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC), Gene Expression Omnibus (GEO), Oncomine, and cBioPortal databases. The prognostic value of SLC7A11 was assessed through survival analysis, Receiver operating characteristic curve (ROC) analysis, independent prognostic analysis, clinical subgroup analysis, and nomogram. Its prognostic value was also validated in the ICGC and GSE29607 cohorts. Gene set enrichment analysis (GSEA) was employed to investigate the effects of SLC7A11 on multiple metabolic pathways. The CIBERSORT algorithm and single‐sample gene set enrichment analysis (ssGSEA) method were applied to evaluate the effects of SLC7A11 on the tumor immune microenvironment (TIM). SLC7A11’s therapeutic correlations were analyzed using the GSE87121, GSE67501, and GSDC datasets. Finally, the biofunctions of SLC7A11 in renal cancer cells and ferroptosis were ascertained by MTT, wound healing, transwell, and western blot assays.

Results

Through multiple datasets, SLC7A11 was found to be markedly upregulated in RCC. In terms of prognosis, SLC7A11 overexpression conferred a worse prognosis and was identified as an independent prognostic factor. Its prognostic value was validated in ICGC cohort. Moreover, high SL7CA11 expression could stimulate nucleotides, fatty acids, and amino acid metabolism to meet the proliferative consumption of tumor cells. As for the immune effect, SLC7A11 suppressed antitumor immunity by reducing the abundances of CD8+ T and NK cells. Regarding the therapeutic response, SLC7A11 expression was not correlated with the sensitivities of most chemotherapy and targeted drugs. Finally, SLC7A11 promoted the proliferation, migration, and invasion of renal cancer cells by enhancing GPX4 output, which in turn inhibits ferroptosis.

Conclusions

SLC7A11 not only deeply influences RCC prognosis and TIM, but also promotes RCC progression by inhibiting ferroptosis and inducing metabolic reprogramming. In addition, SLC7A11 weakly affects the therapeutic effect and sensitivities of multiple chemotherapy and targeted drugs.

Phase II and biomarker study of programmed cell death protein 1 inhibitor nivolumab and metronomic cyclophosphamide in paediatric relapsed/refractory solid tumours: Arm G of AcSé-ESMART, a trial of the European Innovative Therapies for Children With Cancer Consortium

PURPOSE

AcSé-ESMART is a European multicentre, proof-of-concept multiarm phase I/II platform trial in paediatric patients with relapsed/refractory cancer. Arm G assessed the activity and safety of nivolumab in combination with metronomic cyclophosphamide +/- irradiation.

EXPERIMENTAL DESIGN

Following a Phase II Simon two-stage design, nivolumab was administered intravenously at 3 mg/kg every 2 weeks of a 28-day cycle, oral cyclophosphamide at 25 mg/m2 twice a day, 1 week on/1 week off. The primary endpoint was objective response rate. Irradiation/radioablation of primary tumour or metastasis could be administered as per physician's choice. Biomarker evaluation was performed by tumour immunohistochemistry, whole exome and RNA sequencing, and immunophenotyping of peripheral blood by flow cytometry.

RESULTS

Thirteen patients were treated with a median age of 15 years (range: 5.5-19.4). The main histologies were high-grade glioma, neuroblastoma, and desmoplastic small round cell tumour (DSRCT). The safety profile was similar to those of single-agent nivolumab, albeit haematologic toxicity, mainly lymphocytopenia, was commonly reported with the addition of cyclophosphamide +/- irradiation. Two patients with DSRCT and ependymoma presented unconfirmed partial response and prolonged disease stabilisation. Low mutational load with modest intratumour CD3+ T-cell infiltration and immunosuppressive tumour microenvironment were observed in the tumour samples. Under combined treatment, no positive modulation of circulating T cells was displayed, while derived neutrophil-to-lymphocyte ratio increased.

CONCLUSIONS

Nivolumab in combination with cyclophosphamide was well tolerated but had limited activity in this paediatric setting. Metronomic cyclophosphamide did not modulate systemic immune response that could compensate limited T-cell infiltration and the immunosuppressive tumour microenvironment. CLINICALTRIALS.

GOV IDENTIFIER

NCT2813135.

Unusual metastasis from renal cell cancer after partial nephrectomy and sequential targeted therapy

INTRODUCTION

Metastatic renal cell carcinoma is treated with various regimens. As their outcomes are improving and follow-up periods are growing longer, the rate of unusual visceral metastases may increase.

CASE PRESENTATION

A 68-year-old man diagnosed with lung, pancreatic, and renal metastases 9 years after left partial nephrectomy and a diagnosis of pT1a clear cell renal cell carcinoma started molecular targeted therapy using sunitinib. Nine years after the initiation of targeted therapy, a mass lesion in the esophagus was revealed by follow-up computed tomography, and endoscopic mucosal resection of the esophageal metastatic lesion was performed. One year later, a bladder tumor was detected by follow-up computed tomography. The patient underwent transurethral resection of the bladder tumor. Histological evaluation of both resected specimens disclosed clear cell renal cell carcinoma.

CONCLUSION

We present a valuable case of metachronous esophagus and bladder metastases from renal cell carcinoma in a long-term follow-up.

Impact of Serum γ-Glutamyltransferase on Overall Survival in Patients with Metastatic Renal Cell Carcinoma in the Era of Targeted Therapy

BACKGROUND

γ-Glutamyltransferase (GGT) is a marker of oxidative stress. Elevated serum GGT is linked to poor survival in various malignancies; however, there are no data on metastatic renal cell carcinoma (mRCC). Additionally, GGT expression in cancer tissues remains largely unknown.

OBJECTIVE

The present study was designed to determine the prognostic role of serum GGT in patients with mRCC and the association between systemic and local GGT levels.

PATIENTS AND METHODS

Pretherapeutic serum GGT and other clinicopathological parameters were retrospectively compared with overall survival (OS) in 146 consecutive patients with mRCC receiving tyrosine kinase inhibitor therapy. GGT expression was analyzed in 65 resected specimens using immunohistochemistry.

RESULTS

A total of 82 patients (56%) died during the follow-up period (median 34.9 months). Median OS was 16.0 months and 36.8 months in patients with elevated GGT levels and without elevated GGT, respectively (P < 0.001). On multivariable analysis, elevated serum GGT was an independent adverse prognostic factor (hazard ratio [HR] 4.04, P < 0.001), together with high neutrophils (HR 2.06, P = 0.041), low albumin (HR 2.00, P = 0.006), high lactate dehydrogenase (HR 2.68, P < 0.001), and high De Ritis ratio (HR 1.97, P = 0.004). Preoperative serum GGT levels were 29, 48, and 109 U/l in patients whose renal cancer cells showed negative to weak, moderate, and strong GGT expression, respectively (P = 0.004).

CONCLUSIONS

Elevated serum GGT was an unfavorable prognostic factor in mRCC, and overexpression of GGT in renal cancer cells might be responsible for elevation of serum GGT.

PD-L1 versus tumor mutation burden: Which is the better immunotherapy biomarker in advanced non-small cell lung cancer?

PD-L1 and tumor mutation burden (TMB) are the most widely used immunotherapy biomarkers to identify populations who would attain clinical benefit, with the higher values predicting better therapeutic efficacy. This review addresses the predictive values and unresolved challenges of these two biomarkers. PD-1 and PD-L1 inhibitors have induced durable and effective responses in patients with advanced non-small cell lung cancer, confirmed by multiple clinical trials and real-world studies. Different clinical trials, involving both PD-1/PD-L1 inhibitors alone and combination regimens, adopted either PD-L1 or TMB to stratify the patients, although the predictive capabilities of these two biomarkers are different. In the first-line setting, PD-L1 of 50% or more as a cut-off value can help select candidates for pembrolizumab or atezolizumab monotherapy; however, these two biomarkers poorly predict the efficacy of immunotherapy combination regimens as first-line treatments. In the second-line setting, although patients can benefit from nivolumab regardless of PD-L1 expression, both PD-L1 and blood TMB can be used as biomarkers to find patients suitable for atezolizumab. Except for inaccurate predictiveness, there are many unresolved problems with regard to the two biomarkers, such as the lack of standard detection methods, and their susceptibilities to other dynamic changes. The predictive values of TMB and PD-L1 were low in most circumstances; however, PD-L1 expression greater than ≥ 50% can help select appropriate patients for pembrolizumab and atezolizumab, respectively, as first-line monotherapies. Higher PD-L1 or TMB was associated with greater efficacy for atezolizumab as a second-line monotherapy.

Modified Glasgow Prognostic Score as a Predictor of Prognosis in Metastatic Renal Cell Carcinoma Treated With Nivolumab

BACKGROUND

The modified Glasgow prognostic score (mGPS), which incorporates serum albumin and C-reactive protein levels, reflects systemic inflammation and nutritional status. In this study, we evaluate the role of mGPS as a predictor of prognosis in metastatic renal cell carcinoma treated with nivolumab.

PATIENTS AND METHODS

Forty-five consecutive patients with metastatic renal cell carcinoma receiving nivolumab therapy after tyrosine kinase inhibitor therapy between September 2013 and August 2019 at our institution were retrospectively analyzed. The prognostic factors associated with overall survival were statistically analyzed.

RESULTS

The median follow-up period was 26.4 months. The median progression-free survival and 1- and 3-year progression-free survival rates were 11.6 months, 48.9%, and 17.1%, respectively. The median overall survival and 1- and 3-year overall survival rates were not reached, 88.7%, and 62.3%, respectively. In multivariate analysis, mGPS at the time of nivolumab administration (P < .0001; hazard ratio [HR], 95.7; P = .0004 [Score 1 vs. 0]; HR, 98.9; P = .0002 [Score 2 vs. 0]; and HR, 1.03; P = .971 [Score 2 vs. 1]) was extracted as the strongest predictor for overall survival followed by duration from diagnosis to treatment (P = .0001), lactate dehydrogenase (P = .0005), and lymphocyte count (P = .021). Overall survival curves were distinctly separated between mGPS Score 0 and mGPS Score 1 + 2, with median overall survival periods being not reached and 32.4 months, respectively (P = .0004).

CONCLUSIONS

mGPS was the strongest significant prognostic biomarker in patients with metastatic renal cell carcinoma treated with nivolumab. This simple classification could be useful in clinical practice.

[The content of the soluble forms PD-1 and PD-L1 in blood serum of patients with gastric cancer and their relationship with clinical and morphological characteristics of the disease.]

Results of comparative ELISA investigation of pretreatment sPD-1 and sPD-L1 content in blood plasma of 100 gastric cancer patients at various disease stages aged 25 to 81 years are presented. Control group included 60 practically healthy donors aged 18 - 68 years. Plasma sPD-L1 concentrations did not differ between gastric cancer patients and control group, and sPD-1 levels were statistically significantly lower in patients than in healthy donors (p<0.0001). Positive correlation (R=0.38; p=0.003) was revealed between plasma sPD-1 и sPD-L1 levels in control group and negative (R= -0.26; p=0,009) - in gastric cancer patients. ROC curve revealed the best sPD-1 cut-off level (< 21 pg/ml) with 77% sensitivity and 63.3% specificity, which is not sufficient for its application as diagnostic marker. Statistically significant increase of plasma sPD-L1 from stage I to stage IIIC (R=0.50; p=0.000011) was found. Analysis of associations between the evaluated markers' levels and indices of gastric cancer expansion according to TNM system revealed statistically significant positive associations of plasma sPD -L1 levels with T (tumor invasiondepth) and N (number of affected lymph nodes) indices: R=0.33; p=0.00093, and R=0.27; p=0.0099 respectively. sPD-L1 level was significantly increased in patients with low differentiated adenocarcinoma and cricoid-cell cancer as compared to highly differentiated adenocarcinoma (p=0.02 and p=0.004 respectively); in patients with cricoid-cell cancer it was also higher than in those with moderately differentiated adenocarcinoma (p=0.043) and undifferentiated cancer (p=0.049). Plasma sPD-1 level did not depend on disease stage, TNM system indices and tumor histological structure. Thus, soluble ligand sPD-L1, but not its receptor sPD-1, plasma level is increased in patients with unfavorable clinical and morphological characteristics, may be regarded as potentially valuable prognostic factor for gastric cancer patients' survival, and probably as a predictor of anti - PD-1/PD-L1 treatment efficiency.

Integrative bioinformatics analysis of a prognostic index and immunotherapeutic targets in renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most common malignancies. The immunogenomic landscape signature significantly correlates with the progression and prognosis of RCC. Novel therapeutic targets and prognostic indices in RCC are highly desirable. The TCGA database enables comprehensive immunogenomic landscape analysis. Differentially expressed immune-related genes (IRGs) were obtained from TCGA and GO analyses, and KEGG pathway analyses were performed to explore their functions and molecular mechanisms. Multivariable Cox analysis was utilized to calculate the risk score of each patient and locate survival-associated IRGs, thereby constructing a novel immune-related gene-based prognostic index (IRGPI). The correlation between IRGPI and immune cell infiltration was also investigated. A total of 41 differentially expressed IRGs were notably related to prognosis in RCC. GO functions and KEGG pathway analyses demonstrated that these genes were primarily associated with the tumour immune response and cytokine-cytokine receptor interaction pathway. An IRGPI based on seventeen survival-associated differentially expressed IRGs was constructed and exhibited a moderate predictive value in the prognosis of RCC patients and a powerful identification ability in refining the risk stratification of RCC patients. A close correlation was found between IRGPI and specific clinicopathological parameters, including age, gender, pathological stage, tumour stage, lymph node metastasis and distant metastasis. A positive correlation was found between IRGPI and the infiltration levels of neutrophils, dendritic cells, CD8+ T cells and B cells. Our results demonstrated the clinical significance and potential function of IRGs, providing additional data for prognostic risk prediction and immunotherapeutic target selection in RCC.

Decline of programmed death-1-positive circulating T regulatory cells predicts more favourable clinical outcome of patients with melanoma under immune checkpoint blockade

BACKGROUND

The role of T regulatory lymphocytes (Tregs) and their immunosuppressive mechanisms in the context of programmed death (PD)-1 blockade is not completely understood.

OBJECTIVES

To assess the impact of PD-1-blocking antibody treatment on Treg subpopulations in the blood.

METHODS

We studied circulating Treg subpopulations in patients with melanoma under nivolumab or pembrolizumab treatment using flow cytometry and correlated these findings with clinical outcomes.

RESULTS

These analyses revealed that the frequency of CD4⁺  CD25⁺⁺  CD127^-  PD-1⁺ lymphocytes (PD-1⁺ Tregs) significantly decreased after the first cycle of immunotherapy (23% vs. 8·6%, P = 0·043). Compared with patients who did not show a significant decline of PD-1⁺ Tregs after the first treatment, those who did had better clinical outcomes with respect to progression-free survival (PFS, P = 0·022) and melanoma-specific death (MSD, P = 0·0038). Multivariate analysis confirmed that a significant decline of PD-1⁺ Tregs in peripheral blood after the first treatment cycle is a significant predictor of more favourable PFS and MSD (P = 0·04 and 0·017, respectively). Interestingly, the occurrence of immune-related adverse events was also an independent predictor for decreased risk of MSD (P = 0·047; odds ratio 0·064, 95% confidence interval 0·0042-0·97).

CONCLUSIONS

We provide preliminary evidence that circulating PD-1⁺ Tregs rapidly decline after the initiation of treatment with PD-1-blocking antibodies, which is associated with reduced risk of melanoma progression and MSD. Patients showing no decrease of these PD-1⁺ Tregs in peripheral blood are characterized by an impaired response to immune checkpoint blockade and worse outcome. What's already known about this topic? Programmed death (PD)-1-blocking antibodies are highly effective in melanoma treatment. However, more than half of patients do not benefit from this therapy and to date it is difficult to predict which patients will respond to it. What does this study add? PD-1-blocking antibody therapy rapidly results in a decline of circulating PD-1⁺ T regulatory cells (Tregs). What is the translational message? Patients showing a decrease of PD-1⁺ Tregs appear to have better clinical outcome under PD-1 treatment.

Overview of current and future systemic therapy for metastatic renal cell carcinoma

Since the 2000s, there have been dramatic advances in the treatment of metastatic renal cell carcinoma (mRCC), including drugs targeting vascular endothelial growth factor (VEGF) and mammalian target of rapamycin (mTOR) pathways. The first VEGF inhibitors approved for mRCC were sorafenib and sunitinib. Subsequently, two mTOR inhibitors (everolimus and temsirolimus) and other VEGF inhibitors (pazopanib and axitinib) were approved. Overall survival (OS) of mRCC patients has significantly increased during this period. Two novel VEGF inhibitors have recently been approved overseas, including cabozantinib and lenvatinib. Additionally, the recent advent of immunotherapy with checkpoint inhibitors has led to significant changes in the treatment of mRCC. The PD-1 inhibitor nivolumab improved the OS rate of patients with mRCC following VEGF inhibitors. Moreover, the CheckMate 214 trial demonstrated the benefit of nivolumab plus ipilimumab combination therapy in OS and objective response rate in treatment-naive intermediate- and poor-risk mRCC. In this review, current evidence related to the clinical use of targeted therapies and checkpoint inhibitors for the treatment of patients with mRCC is discussed. In addition, we review ongoing trials investigating combinations of checkpoint inhibitors with targeted agents and the identification of biomarkers to guide patient selection and enable individualization of therapy.

The evolving role of cytoreductive nephrectomy: incorporating genomics of metastatic renal cell carcinoma into treatment decisions

PURPOSE OF REVIEW

Recent publications evaluating cytoreductive nephrectomy in the era of targeted therapy emphasize the importance of patient selection. We reviewed the predictive role of genetic alterations in patients with metastatic renal cell carcinoma (mRCC) undergoing cytoreductive nephrectomy.

RECENT FINDINGS

Studies evaluating the association between genetic alterations and outcomes following systemic treatment for mRCC include mainly patients after cytoreductive nephrectomy. Expression of proangiogenic genes, single nucleotide polymorphisms involving genes of the vascular-endothelial growth factor (VEGF) pathway and somatic mutations of chromatin remodeling genes were associated with response to VEGF-targeted therapy. Outcomes following treatment with mammalian target of rapamycin (mTOR) inhibitors were initially associated with mTOR/TSC1/TSC2 mutations; however, subsequent studies did not validate these findings but rather found an association between loss of PTEN expression and PBRM1 mutations and improved outcomes. Loss of PBRM1 was initially linked to response to immunotherapy; however, larger studies question this association and showed high expression of T-effector gene signature predicted improved outcome. Primary tumors with low intratumor heterogeneity but elevated somatic copy-number alterations were associated with rapid progression at multiple sites.

SUMMARY

Genetic alterations may help select patients for cytoreductive nephrectomy and optimize timing of treatment. Intratumor heterogeneity and genetic discordance between primary and metastatic tumors may limit clinical applicability. Future studies should evaluate approaches to overcome these limitations.

Cancer Immunotherapies

The enhanced understanding of immunology experienced over the last 4 decades afforded through the tools of molecular biology has recently translated into cancer immunotherapy becoming one of the most exciting and rapidly expanding fields. Human cancer immunotherapy is now recognized as one of the pillars of treatment alongside surgery, radiation, and chemotherapy. The field of veterinary cancer immunotherapy has also rapidly advanced in the last decade with a handful of commercially available products and a plethora of investigational cancer immunotherapies that will hopefully expand the veterinary oncology treatment toolkit over time.

Overexpression of Smac by an Armed Vesicular Stomatitis Virus Overcomes Tumor Resistance

Despite reports of successful clinical cases, many tumors appear to resist infection by oncolytic viruses (OVs). To circumvent this problem, an armed vesicular stomatitis virus was constructed by inserting a transgene to express Smac/DIABLO during virus infection (VSV-S). Endogenous Smac in HeLa cells was diminished during wtVSV infection, whereas the Smac level was enhanced during VSV-S infection. Apoptosis was readily induced by VSV-S, but not wtVSV, infection. More importantly, the tumor volume was reduced to a larger extent when xenografts of 4T1 cells in BALB/c mice and OV-resistant T-47D cells in nude mice were intratumorally injected with VSV-S. VSV-S represents a novel mechanism to overcome tumor resistance, resulting in more significant tumor regression due to enhanced apoptosis.

Discordancy and changes in the pattern of programmed death ligand 1 expression before and after platinum-based chemotherapy in metastatic gastric cancer

BACKGROUND

Our goal was to evaluate changes in PD-L1 expression in primary tumours of metastatic gastric cancer before and after chemotherapy.

METHODS

We evaluated the PD-L1 expression of 72 patients with primary gastric cancer, before and after palliative first-line platinum-based chemotherapy, between January 2015 and March 2017. The PD-L1 ratio was defined as pre-chemotherapy PD-L1 expression divided by the post-chemotherapy PD-L1 expression.

RESULTS

In 30 patients with PD-L1 negative pre-chemotherapy, 12 (40%) were positive post-chemotherapy; among the 42 patients with PD-L1 positive pre-chemotherapy, 24 (57.1%) were negative post-chemotherapy. The degree of PD-L1 expression decreased from 58.3% before chemotherapy to 41.7% after chemotherapy (P = 0.046). Among patients with complete response/partial response (CR/PR), the degree of PD-L1 expression decreased (P = 0.002), as well as PD-L1 positivity with statistical significance (P = 0.013) after chemotherapy, but not among patients with stable disease/progressive disease (SD/PD). Higher disease control rates (CR/PR/SD) were observed in patients with an elevated PD-L1 ratio (P = 0.043). Patients with a high PD-L1 ratio (> 1) were found to be associated with a better progression-free survival (HR 0.34, 95% CI 0.17-0.67, P = 0.002).

CONCLUSIONS

PD-L1 expression can change during chemotherapy. Moreover, changes in patterns of PD-L1 expression might be associated with patient prognosis and response to chemotherapy.

The challenges of checkpoint inhibition in the treatment of multiple myeloma

Despite significant improvements in the overall survival of patients with multiple myeloma (MM) over the past 15 years, the disease remains incurable. Treatment options are limited for patients who have relapsed or are refractory to immunomodulatory drugs (IMiDs), proteasome inhibitors, and monoclonal antibodies. In these patients, immunotherapies such as checkpoint inhibitors, oncolytic vaccines, and chimeric antigen receptor (CAR) T cells provide a potentially effective alternative treatment. While checkpoint inhibitors are effective in prolonging overall survival in some patients with advanced solid cancers and Hodgkin lymphoma, they have not demonstrated significant activity as a single agent in MM. In fact the combination of checkpoint inhibitors with IMiDs was recently found to increase the risk of death in myeloma patients. These challenges highlight the need for a better understanding of immune dysregulation in myeloma patients, and the mechanisms of action of- and resistance to- checkpoint inhibitors. In this review, we summarize immune dysfunction in patients with MM, and review the preclinical and clinical data regarding checkpoint inhibitors in myeloma. We conclude by proposing strategies to improve the efficacy and safety of checkpoint inhibitors in this population.

Role of systemic inflammatory response markers in urological malignancy

The systemic inflammatory response is associated with survival in patients with a variety of cancers. This inflammatory response is measured in the peripheral blood, and can be monitored using two categories of indices: concentration of specific serum proteins (albumin, C-reactive protein) and differential blood cell count (neutrophils, lymphocytes and platelets). Furthermore, combinations of these indices, such as the Glasgow Prognostic Score, which consists of the serum C-reactive protein and albumin level; the neutrophil-to-lymphocyte ratio; the platelet-to-lymphocyte ratio; and the prognostic nutritional index, which is based on peripheral blood lymphocyte count and serum albumin level, have also been evaluated and compared in cancer research. To date, there are hundreds of studies that have shown the prognostic value of systemic inflammatory response markers in patients with urological cancer. Most studies have evaluated the prognostic and predictive role of the pretreatment value of the markers, although some have focused on the role of the post-treatment value at specific points during the clinical course. The advantages of systemic inflammatory response markers are that they are easily measurable and inexpensive in the clinical setting. However, it is important to consider how clinicians use these markers in clinical practice. The present review provides a concise overview regarding systemic inflammatory markers in urological cancers, specifically C-reactive protein, Glasgow Prognostic Score/modified Glasgow Prognostic Score, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and prognostic nutritional index.

Modern approaches to kidney cancer immunotherapy

Kidney cancer is a heterogeneous group of malignant tumors that develop from cells of the proximal convoluted tubules of the kidney. In Russia renal cell carcinoma holds the 2nd place after prostate cancer among tumors of genitourinary system. The main method of renal cell carcinoma treatment is radical nephrectomy, at the same time, high resistance of kidney cancer to chemotherapy and a weak response to hormone treatment are noted, and the effectiveness of cytokine therapy (interleukin 2, interferon alfa) does not exceed 18–20 %. The introduction into clinical practice of modern immune system affecting drugs has changed the disease prognosis for many patients with various malignant neoplasms. Currently, active development of immunotherapeutic drugs directed against inhibitory receptors of T-cells, the so-called “immunity control points” takes place, the most studied among these drugs are anti-CTLA-4 (cytotoxic T-lymphocyte associated protein 4) and anti-PD-1 (рrogrammed cell death pathway 1)/PD-L1 (programmed death ligand 1) monoclonal antibodies. In this review a detailed description of the PD-1 receptor and its PD-L1 ligand, as well as the prognostic and predictive significance of their expression in various types of renal cell carcinoma and the role in suppressing the antitumor T-cell immune response are presented. Blockade of PD-1/PD-L1 enhances antitumor immunity reducing the amount and/or immunosuppressive activity of regulatory T-cells (suppressors) and restoring the activity of effector T-cells that leads to an enhancement of the antitumor immune response. The blockade of PD-1 also stimulates proliferation of memory B-cells. In this regard, drugs that suppress the function of PD-1 are now widely used in the treatment of cancer including kidney cancer. The authors provide a list of promising drugs acting on PD-1/PD-L1 system used in renal cell carcinoma: nivolumab, pembrolizumab and some others. The results of clinical studies se of immunotherapeutic drugs in kidney cancer are analyzed.

Recent advances in medical therapy for metastatic urothelial cancer

Cytotoxic chemotherapy has been the mainstay of medical therapy for metastatic urothelial cancer. Currently, the gemcitabine/cisplatin regimen is widely used worldwide as the standard first-line medical treatment. Very recently, in 2017, pembrolizumab, a highly selective, humanized monoclonal IgG4κ isotype antibody against programmed death 1, was approved as a second-line treatment to be used after platina-based chemotherapy for metastatic urothelial cancer in Japan. Based on its promising anti-tumor efficacy and manageable safety profile as demonstrated in the phase III KEYNOTE-045 trial, pembrolizumab therapy is expected to be rapidly introduced for treating metastatic urothelial cancer in clinical practice. The paradigm of medical treatment for patients with metastatic UC is dramatically changing through the introduction of this and other immune-checkpoint inhibitors. In this article, we provide a brief overview of these immune-checkpoint inhibitors and a comprehensive summary of the use of cytotoxic chemotherapy for metastatic urothelial cancer, including ongoing clinical trials.

Clinicopathologic implications of CD8+/Foxp3+ ratio and miR-574-3p/PD-L1 axis in spinal chordoma patients

Currently, little is known about the interactions between microRNAs (miRNAs) and the PD-1/PD-L1 signaling pathway in chordoma, and data discussing the role of the immune milieu in chordoma prognosis are limited. We aimed to analyze the relationship between PD-L1, miR-574-3p, microenvironmental tumor-infiltrating lymphocytes (TILs) and clinicopathological features of spinal chordoma patients. PD-L1 expression and TILs (including Foxp3+, CD8+, PD-1+ and PD-L1+) were assessed by immunohistochemistry in tumor specimens of 54 spinal chordoma patients. MiRNAs microarray and bioinformatical analysis were used to identify miRNAs potentially regulating PD-L1 expression, which were further validated by quantitative RT-PCR. miR-574-3p was identified to potentially regulate PD-L1 expression in chordoma, which inversely correlated with PD-L1. Positive PD-L1 expression on tumor cells was associated with advanced stages (P = 0.041) and TILs infiltration (P = 0.005), whereas decreased miR-574-3p level correlated with higher muscle invasion (P = 0.012), more severe tumor necrosis (P = 0.022) and poor patient survival. Importantly, a patient subgroup with PD-L1+/miR-574-3plow chordoma phenotype was significantly associated with worse local recurrence-free survival (LRFS) (P = 0.026). PD-1+ TILs density was associated with surrounding muscle invasion (P = 0.014), and independently portended poor LRFS (P = 0.040), while PD-L1+ TILs showed tendencies of less aggressive clinical outcomes. Multivariate analysis of OS only found CD8+/Foxp3+ ratio to be independent prognostic factor (P = 0.022). These findings may be useful to stratify patients into prognostic groups and provide a rationale for the use of checkpoint blockade therapy, possibly by administering miR-574-3p mimics, in spinal chordoma.

The prognostic value of programmed cell death ligand 1 expression in non-Hodgkin lymphoma: a meta-analysis

Objective:

Although the prognostic value of programmed cell death-ligand 1 (PD-L1) expression in non-Hodgkin lymphoma (NHL) has been evaluated in many studies, the results remain controversial. To investigate the prognostic role of PD-L1 expression and the association between PD-L1 expression and clinicopathological features of NHL, we performed a meta-analysis.

Methods:

The PubMed, EMBASE, and Cochrane Library databases were searched up to November 30, 2017. The hazard ratio (HR), 95% confidence interval (CI), and odds ratios (OR) with 95% CIs were combined to evaluate the association of PD-L1 expression with overall survival (OS) and clinicopathological features. Review manager 5.3 and STATA 12.0 were used in this meta-analysis.

Results:

A total of 2,005 patients across nine studies were enrolled in our meta-analysis, and the pooled results showed that high PD-L1 expression was associated with a poor prognosis (HR=2.04, 95% CI: 1.18–3.54, P=0.01). In the subgroup analysis according to histology types, pooled results demonstrated that an increased PD-L1 expression was an unfavorable prognostic factor for diffuse large B-cell lymphoma (HR=1.92, 95% CI: 1.06–3.48, P=0.03) but not for natural killer/T-cell lymphoma (HR=2.41, 95% CI: 0.47–12.22, P=0.29). Pooled ORs indicated that PD-L1 expression was higher in NHL with international prognostic indices of ≥3. However, PD-L1 expression had no correlation with gender, age, disease stage, lactate dehydrogenase level, B symptoms, and germinal center B-cell-like lymphoma.

Conclusions:

High PD-L1 expression was a poor prognostic biomarker in patients with NHL. Because of our limited sample size, high-quality studies with larger sample sizes are needed to validate our results.

Similarity and difference in tumor-infiltrating lymphocytes in original tumor tissues and those of in vitro expanded populations in head and neck cancer

Though adoptive tumor-infiltrating lymphocyte (TIL) therapy has been explored in clinical trials for many years, there is little information for the clonotype composition between TILs in original tumor tissues and TILs that were in vitro expanded and infused to cancer patients. To investigate the similarity/difference in TILs in original tumor tissues and those of in vitro expanded populations in squamous cell carcinoma of head and neck (SCCHN) as well as their correlation with somatic mutations in cancer cells, we performed whole exome analysis, expression profile analysis of immune-related genes, and T cell receptor (TCR) analysis of original TILs and in vitro expanded TILs in 8 surgically-resected HPV-negative fresh tumors with SCCHN. We found an unusually high number of non-synonymous somatic mutations (4290, 1779 and 901 mutations) in three SCCHN tumors, in which we identified mutations in mismatch repair genes, MSH2 or MSH4, or a DNA polymerase gene, POLE. Interestingly, dominant TCR clonotypes of expanded CD8⁺ TILs derived from these three tumors revealed high similarity to those in original tumors while for remaining tumors with the lower mutational load, we found that T cell clonotypes between TILs in original tumor tissues and those expanded in vitro were almost entirely different. Our findings might provide clinically useful information for identification of tumor-antigen-specific T cell clones that may lead to further improvement of adoptive TIL therapy for SCCHN patients.

Impressive response to immunotherapy in a metastatic gastric cancer patient: could somatic copy number alterations help patient selection?

Background

Metastatic gastric cancer (GC) is an incurable and aggressive disease with a poor prognosis. Immunotherapy is an attractive approach for treating patients with cancer, and studies using immunotherapy have shown promising results in melanoma, kidney and non-small cell lung cancers, among others.

Case presentation

We present a case of a 50-year-old woman with metastatic GC whose cancer had progressed after first-line chemotherapy and who received pembrolizumab as an experimental treatment. Molecular analyses showed that her tumor was negative for PD-L1 expression, contained microsatellite stability and several focal somatic copy number alterations. The patient experienced an almost complete response after eleven cycles of treatment. Her symptoms related to the disease disappeared, and the medication was well tolerated.

Conclusions

Despite reports of promising responses in some patients, immunotherapy is not suitable for all patients; therefore, we explored the molecular characteristics that could explain the exceptional response and clinical benefits observed in our patient.

Role of PD-1 in Immunity and Diseases

Immunity developed to defend our bodies from foreign particles, including bacteria and viruses. Although effector cells responsible for acquired immunity, mainly T cells, and B cells, are able to distinguish self from non-self, they sometimes attack the body's tissues because of imperfect central tolerance. Several immune check points developed to limit overactivation of these cells. One of the most important immune checkpoints is programmed cell death-1 (PD-1), which is expressed mainly on activated lymphocytes. As its ligands (PD-Ls) are expressed widely in the body and affect the responses against self and foreign antigens, controlling PD-1/PD-L interactions enables the management of several immune-related diseases such as autoimmune disease, virus infection, and cancers. Currently, the strategy of PD-1/ PD-L1 blockade has already been applied to clinical cancer therapy, providing evidences that PD-1 signal is one of the main factors of cancer immune escape in humans. The dramatic efficacy of PD-1 blockade in cancer immunotherapy, promises the control of other immune diseases by PD-1 signal modulation. In this review, we summarize the history of PD-1, subsequent basic studies, and their application to the clinic.