CD3-zetachain expression of intratumoral lymphocytes is closely related to survival in gastric carcinoma patients

Key links in the physiological regulation of the immune system and disease induction: T cell receptor -CD3 complex

T cell receptor (TCR) is a kind of surface marker that are specific to T cells. The TCR regulates T cell function and participates in the body's immunological response to prevent immune dysregulation and inflammatory reactions by identifying and binding exogenous antigens. Due to its brief intracellular segment, TCR requires intracellular molecules to assist with signaling. Among these, the CD3 molecule is one of the most important. The CD3 molecule involves in TCR structural stability as well as T cell activation signaling. A TCR-CD3 complex is created when TCR and CD3 form a non-covalent bond. Antigen recognition and T cell signaling are both facilitated by the TCR-CD3 complex. When a CD3 subunit is absent, a TCR-CD3 complex cannot form, and none of the subunits is transported to the cell surface. Thus, T cells cannot develop. Consequently, research on the physiological functions and potential pathogenicity of CD3 subunits can clarify the pathogenesis of immune system diseases and can offer fresh approaches to the treatment of it. In this review, the structure and function of the TCR-CD3 complex in the immune system was summarized, the pathogenicity of each CD3 subunit and therapeutic approaches to related diseases was explored and research directions for the development of new targeted drugs was provided.

CD3ζ as a novel predictive biomarker of PD-1 inhibitor resistance in melanoma

Malignant melanoma is the most lethal form of skin cancer, and its incidence rates are increasing in Europe, America, and Oceania countries. Despite immune checkpoint inhibitors, such as PD-1 inhibitors, have been shown to have significant therapeutic effects on malignant melanoma, many patients are unresponsive to these treatments, even emerged resistance. There is an urgent need to discover novel biomarkers that might distinguish resistant patients from responders. In this study, we used a series of bioinformatics analyses and experimental validation. The GSE65041 was used for differential expression analysis. Kaplan-Meier was used to assess the prognostic value. ESTIMATE, ssGSEA, EPIC, TIMER, quanTiseq and MCPcounter for estimation of immune infiltration in the tumor microenvironment. We eventually identified that CD3ζ was significantly down-regulated in IHC PD-L1(-) melanoma patients. Low level of CD3ζ expression possessed a poor prognosis. CD3ζ low expression population is significantly associated with lower immune infiltration. In vivo experiment, CD3ζ expression was significantly down-regulated in mice melanoma after intradermally injected with B16-F10R cells. Compared to their wildtype counterparts, melanoma resistant mice treated with nivolumab showed significant reductions in tumor volume and weight when adding CD3ζ. In vitro experiment, the addition of CD3ζ increased nivolumab effection on inhibiting B16-F10R cell viability. Our findings indicated that CD3ζ could be a novel predictive biomarker of PD-1 inhibitor resistance in melanoma.

A novel prognostic biomarker CD3G that correlates with the tumor microenvironment in cervical cancer

Cervical cancer (CESC) is the fourth most common and death-causing gynecological cancer, mostly induced by infection of human papillomavirus (HPV). Multiple components of the tumor microenvironment (TME), such as tumor infiltrating immune cells, could be targets of immunotherapy for HPV-related CESC. However, little is known about the TME of CESC until now. Here, we aimed to uncover the pathogenesis as well as to identify novel biomarkers to predict prognosis and immunotherapy efficacy for CESC. Combining the transcriptomic data and clinical characteristics, we identified differentially expressed genes in CESC samples from TCGA database by comparing the two groups with different ImmuneScore and StromalScore. Next, we detected ten key genes based on the PPI network and survival analyses with the univariate Cox regression model. Thereafter, we focused on CD3G, the only gene exhibiting increased RNA and protein expression in tumors by multiple analyses. Higher CD3G expression was associated with better survival; and it was also significantly associated with immune-related pathways through GSEA analysis. Furthermore, we found that CD3G expression was correlated with 16 types of TICs. Single cell RNA-sequencing data of CD3G in lymphocytes subgroup indicated its possible role in HPV defense. Hence, CD3G might be a novel biomarker in prognosis and immunotherapy for CESC patients.

Immune Classification and Immune Landscape Analysis of Triple-Negative Breast Cancer

Background: To classify triple-negative breast cancer (TNBC) immunotyping using the public database, analyze the differences between subtypes in terms of clinical characteristics and explore the role and clinical significance of immune subtypes in TNBC immunotherapy.

Methods: We downloaded TNBC data from the cBioPortal and GEO databases. The immune genes were grouped to obtain immune gene modules and annotate their biological functions. Log-rank tests and Cox regression were used to evaluate the prognosis of immune subtypes (IS). Drug sensitivity analysis was also performed for the differences among immune subtypes in immunotherapy and chemotherapy. In addition, dimension reduction analysis based on graph learning was utilized to reveal the internal structure of the immune system and visualize the distribution of patients.

Results: Significant differences in prognosis were observed between subtypes (IS1, IS2, and IS3), with the best in IS3 and the worst in IS1. The sensitivity of IS3 to immunotherapy and chemotherapy was better than the other two subtypes. In addition, Immune landscape analysis found the intra-class heterogeneity of immune subtypes and further classified IS3 subtypes (IS3A and IS3B). Immune-related genes were divided into seven functional modules (The turquoise module has the worst prognosis). Five hub genes (RASSF5, CD8A, ICOS, IRF8, and CD247) were screened out as the final characteristic genes related to poor prognosis by low expression.

Conclusions: The immune subtypes of TNBC were significantly different in prognosis, gene mutation, immune infiltration, drug sensitivity, and heterogeneity. We validated the independent role of immune subtypes in tumor progression and immunotherapy for TNBC. This study provides a new perspective for personalized immunotherapy and the prognosis evaluation of TNBC patients in the future.

Identification of Biomarkers for Cervical Cancer Radiotherapy Resistance Based on RNA Sequencing Data

Cervical cancer as a common gynecological malignancy threatens the health and lives of women. Resistance to radiotherapy is the primary cause of treatment failure and is mainly related to difference in the inherent vulnerability of tumors after radiotherapy. Here, we investigated signature genes associated with poor response to radiotherapy by analyzing an independent cervical cancer dataset from the Gene Expression Omnibus, including pre-irradiation and mid-irradiation information. A total of 316 differentially expressed genes were significantly identified. The correlations between these genes were investigated through the Pearson correlation analysis. Subsequently, random forest model was used in determining cancer-related genes, and all genes were ranked by random forest scoring. The top 30 candidate genes were selected for uncovering their biological functions. Functional enrichment analysis revealed that the biological functions chiefly enriched in tumor immune responses, such as cellular defense response, negative regulation of immune system process, T cell activation, neutrophil activation involved in immune response, regulation of antigen processing and presentation, and peptidyl-tyrosine autophosphorylation. Finally, the top 30 genes were screened and analyzed through literature verification. After validation, 10 genes (KLRK1, LCK, KIF20A, CD247, FASLG, CD163, ZAP70, CD8B, ZNF683, and F10) were to our objective. Overall, the present research confirmed that integrated bioinformatics methods can contribute to the understanding of the molecular mechanisms and potential therapeutic targets underlying radiotherapy resistance in cervical cancer.

CD247 expression is associated with differentiation and classification in ovarian cancer

Ovarian cancer (OC) is one of the most common malignant tumors in female reproductive system and most OC cases are diagnosed at an advanced stage with the overall 5-year survival rate below 40%. The function of CD247 enhances T-cell antigen receptor (TCR) signaling cascade and it is necessary for assembling of the TCR/CD3 complex on the surface of T lymphocytes. It is well established that defective CD247 function leads to impaired activation of T cells upon engagement of the TCR.Flow cytometry was used to examine the difference of CD247 T lymphocyte between the OC and ovarian cyst, immunohistochemistry analysis was used to investigate the correlation between CD247 expression and clinicopathologic features of epithelial OC patients.Our study showed that the expression of CD247 in peripheral blood lymphocytes from patients with OC is decreased compared with ovarian cyst patients and the expression of CD247 in tumor infiltrating lymphocytes with cancer tissue is decreased compared with adjacent tissues. We showed that abnormal expression of CD247 was related with differentiation and classification in OC.Our findings suggested that CD247-targeted treatment could be used as a potential therapeutic strategy for OC.

The Prognostic Role of CD8+ T Lymphocytes in Childhood Adrenocortical Carcinomas Compared to Ki-67, PD-1, PD-L1, and the Weiss Score

Adrenocortical carcinoma (ACC) is a rare disease among children. Our goal was to identify prognostic biomarkers in 48 primary ACCs from children (2.83 ± 2.3 y; mean age ± SD) by evaluating the tumor stage and outcome for an age of diagnosis before or after 3 years, and association with ACC cluster of differentiation 8 positive (CD8+) cytotoxic T lymphocytes (CD8+-CTL) and Ki-67 immunohistochemical expression (IHC). Programmed death 1(PD-1)/Programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) in ACC was analyzed in a second, partially overlapping cohort (N = 19) with a similar mean age. All patients and control children were carriers of the germline TP53 R337H mutation. Survival without recurrence for less than 3 years and death unrelated to disease were excluded. Higher counts of CD8+-CTL were associated with patients diagnosed with ACC at a younger age and stage I, whereas a higher percentage of the Ki-67 labeling index (LI) and Weiss scores did not differentiate disease free survival (DFS) in children younger than 3 years old. No PD-1 staining was observed, whereas weakly PD-L1-positive immune cells were found in 4/19 (21%) of the ACC samples studied. A high CD8+-CTL count in ACC of surviving children is compelling evidence of an immune response against the disease. A better understanding of the options for enhancement of targets for CD8+ T cell recognition may provide insights for future pre-clinical studies.

Prognostic role of tumor-infiltrating lymphocytes in gastric cancer: A systematic review and meta-analysis

BACKGROUND

The potential prognostic value of tumor-infiltrating lymphocytes (TILs) in gastric cancer remains controversial. This meta-analysis examines the association between TILs and survival outcomes in gastric cancer.

METHODS

Twenty-two eligible studies were identified using the PubMed and Google Scholar databases. The combined sample size of the 22 studies was 2941, and the median sample size of the individual studies was 122 patients (52-220). The main clinical outcomes examined were overall cancer survival (OCS) and overall cancer relapse-free survival (OCRFS).

RESULTS

Tumor tissue CD3(+) TILs, indicative of pan-T-cell expression, had a positive effect on survival with a hazard ratio (HR) of 0.64 (95% confidence interval [CI] 0.52-0.78) for OCS, as did the non-FOXP3(+) T-cell subgroup with an HR of 0.66 (95% CI 0.57-0.75), particularly in CD8(+) lymphocytes (HR = 0.63, 95% CI 0.48-0.83). On the contrary, high FOXP3(+) T-cell expression was correlated with reduced OCS, with an HR of 1.75 (95% CI 1.26-2.42). Analysis of the seven studies evaluating OCRFS revealed improved OCRFS with infiltration of non-FOXP3(+) TILs with an HR of 0.59 (95% CI 0.42-0.81) but not FOXP3(+) T lymphocytes with an HR of 1.82 (95% CI 1.30-2.53).

CONCLUSION

The results from this meta-analysis suggest that high expression of TILs, mainly by CD8 lymphocytes, may be a potential prognostic biomarker in patients with gastric cancer.

Tumor Infiltrating Lymphocytes in Uveal Melanoma: A Link with Clinical Behavior?

Experimental and clinical evidence indicate that immunological mechanisms might be important in the clinical course of uveal malignant melanoma (UMM). We analyzed the amount and phenotype of tumor infiltrating lymphocytes (TIL) and the expression of the apoptosis-inducing molecule Fas and its ligand, FasL, on tumor cells and TIL in a selected series of UMM with the aim to establish if a correlation between their expression and the clinical behavior of UMM exists. TIL phenotype and Fas/FasL expression were evaluated by immunohistochemistry in 61 cases of formalin-fixed, paraffin-embedded UMM. Results were compared with the follow-up data of patients. Most of the UMM showed a prevalence of CD8+ CD3+ T lymphocytes, or CD4+ and CD8+ cells in equal amounts. UMM showed a variable expression of FasL, ranging from 0 to > 40% of neoplastic cells. Fas was always expressed in TIL, although with a variable extent. A subgroup of UMM showed in TIL a strongly reduced or even absent expression of TCR ζ-chain, involved in activation of T-lymphocytes. This subgroup was characterized by a worse outcome. We hypothesized that an impaired cytotoxic immune response due to the loss of the ζ-chain expression plays a primary role in the biological course of UMM. Our results indicate that the overcoming of the impairment of TCR function may represent a prerequisite for the development of new therapeutic strategies for managing UMM, suggesting that elimination of tumor cells may be possible by activation of cytotoxic cells present within ocular melanomas.

Prognostic role of tumor-infiltrating lymphocytes in gastric cancer: a meta-analysis

Background

In patients with gastric cancer, the prognostic value of tumor-infiltrating lymphocytes (TILs) is still controversial. A meta-analysis was performed to evaluate the prognostic value of TILs in gastric cancer.

Materials and methods

We identify studies from PubMed, Embase and the Cochrane Library to assess the prognostic effect of TILs in patients with gastric cancer. Fixed-effects models or random-effects models were used estimate the pooled hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS), which depend on the heterogeneity.

Results

A total of 31 observational studies including 4,185 patients were enrolled. For TILs subsets, the amount of CD8⁺, FOXP3⁺, CD3⁺, CD57⁺, CD20⁺, CD45RO⁺, Granzyme B⁺ and T-bet⁺ lymphocytes was significantly associated with improved survival (P < 0.05); moreover, the amount of CD3+ TILs in intra-tumoral compartment (IT) was the most significant prognostic marker (pooled HR = 0.52; 95% CI = 0.43–0.63; P < 0.001). However, CD4⁺ TILs was not statistically associated with patients’ survival. FOXP3+ TILs showed bidirectional prognostic roles which had positive effect in IT (pooled HR = 1.57; 95% CI = 1.04–2.37; P = 0.033) and negative effect in extra-tumoral compartment (ET) (pooled HR = 0.76; 95% CI = 0.60–0.96; P = 0.022).

Conclusions

This meta-analysis suggests that some TIL subsets could serve as prognostic biomarkers in gastric cancer. High-quality randomized controlled trials are needed to decide if these TILs could serve as targets for immunotherapy in gastric cancer.

Extracellular 2'5'-oligoadenylate synthetase 2 mediates T-cell receptor CD3-ζ chain down-regulation via caspase-3 activation in oral cancer

Decreased expression of CD3-ζ chain, an adaptor protein associated with T-cell signalling, is well documented in patients with oral cancer, but the mechanistic justifications are fragmentary. Previous studies in patients with oral cancer have shown that decreased expression of CD3-ζ chain was associated with decreased responsiveness of T cells. Tumours are known to induce localized as well as systemic immune suppression. This study provides evidence that oral tumour-derived factors promote immune suppression by down-regulating CD3-ζ chain expression. 2'5'-Oligoadenylate synthetase 2 (OAS2) was identified by the proteomic approach and our results established a causative link between CD3-ζ chain down-regulation and OAS2 stimulation. The surrogate situation was established by over-expressing OAS2 in a HEK293 cell line and cell-free supernatant was collected. These supernatants when incubated with T cells resulted in down-regulation of CD3-ζ chain, which shows that the secreted OAS2 is capable of regulating CD3-ζ chain expression. Incubation of T cells with cell-free supernatants of oral tumours or recombinant human OAS2 (rh-OAS2) induced caspase-3 activation, which resulted in CD3-ζ chain down-regulation. Caspase-3 inhibition/down-regulation using pharmacological inhibitor or small interfering RNA restored down-regulated CD3-ζ chain expression in T cells induced by cell-free tumour supernatant or rh-OAS2. Collectively these results show that OAS2 leads to impairment in CD3-ζ chain expression, so offering an explanation that might be applicable to the CD3-ζ chain deficiency observed in cancer and diverse disease conditions.

Coexpressed Catalase Protects Chimeric Antigen Receptor-Redirected T Cells as well as Bystander Cells from Oxidative Stress-Induced Loss of Antitumor Activity

Treatment of cancer patients by adoptive T cell therapy has yielded promising results. In solid tumors, however, T cells encounter a hostile environment, in particular with increased inflammatory activity as a hallmark of the tumor milieu that goes along with abundant reactive oxygen species (ROS) that substantially impair antitumor activity. We present a strategy to render antitumor T cells more resilient toward ROS by coexpressing catalase along with a tumor specific chimeric Ag receptor (CAR) to increase their antioxidative capacity by metabolizing H2O2. In fact, T cells engineered with a bicistronic vector that concurrently expresses catalase, along with the CAR coexpressing catalase (CAR-CAT), performed superior over CAR T cells as they showed increased levels of intracellular catalase and had a reduced oxidative state with less ROS accumulation in both the basal state and upon activation while maintaining their antitumor activity despite high H2O2 levels. Moreover, CAR-CAT T cells exerted a substantial bystander protection of nontransfected immune effector cells as measured by CD3ζ chain expression in bystander T cells even in the presence of high H2O2 concentrations. Bystander NK cells, otherwise ROS sensitive, efficiently eliminate their K562 target cells under H2O2-induced oxidative stress when admixed with CAR-CAT T cells. This approach represents a novel means for protecting tumor-infiltrating cells from tumor-associated oxidative stress-mediated repression.

Cancerous HLA class I expression and regulatory T cell infiltration in gastric cancer

BACKGROUND

Since antitumor immune reactions between tumors and intratumoral immunocytes have been verified in several human tumors, immunological therapeutic strategies must be considered to obtain the proper efficacy of tumor shrinkage under these conditions. Human leukocyte antigen (HLA) class I expression in cancer cells and degree of infiltration of regulatory T cells (Tregs) in the stroma have been regarded as important markers of antitumor immune reactions in the context of independent immunological mechanisms. In the current study, we investigated HLA class I expression and Treg cells infiltration in gastric cancer and discussed the clinical implications of this combinatory analysis in gastric cancer.

PATIENTS AND METHODS

A total of 141 gastric cancer patients who received R0 gastrectomy at Kagoshima University Hospital were studied. Immunohistochemically, in 141 gastric cancer patients, HLA class I expression and Treg cell infiltration in cancerous tissue were evaluated using HLA class I (EMR8-5) and forkhead box p3 (FOXP3) monoclonal antibodies. The correlation between clinical factors and tumor-infiltrating Treg cells was analyzed.

RESULTS

HLA class I expression was positively associated with depth of tumor invasion (P < 0.05). Infiltration of Foxp3-positive cells did not correlate with any clinicopathological markers. HLA class I expression had no association with Treg cell infiltration (r = 0.04). A better postoperative outcome was associated with fewer numbers of Treg infiltration (P = 0.034). A combination of HLA and Treg analysis may lead to a more accurate prediction of postoperative outcome (P = 0.02).

CONCLUSIONS

Two different antitumor immunological markers, Treg infiltration and HLA class I expression, affected clinicopathological factors in gastric cancer by different mechanisms. Thus, an immunological combination of HLA class I expression and Treg cell infiltration may more accurately predict postoperative outcome. Immunological balance needs to be restored after evaluation of each immunological deficit in gastric cancer.

Overcoming immunosuppression in the melanoma microenvironment induced by chronic inflammation

Malignant melanoma is known by its rapid progression and poor response to currently applied treatments. Despite the well-documented melanoma immunogenicity, the results of immunotherapeutic clinical trials are not satisfactory. This poor antitumor reactivity is due to the development of chronic inflammation in the tumor microenvironment characterized by infiltrating leukocytes and soluble mediators, which lead to an immunosuppression associated with cancer progression. Using the ret transgenic mouse melanoma model that closely resembles human melanoma, we demonstrated increased levels of chronic inflammatory factors in skin tumors and metastatic lymph nodes, which correlated with tumor progression. Furthermore, Gr1(+)CD11b(+) myeloid-derived suppressor cells (MDSC), known to block tumor-reactive T cells, were enriched in melanoma lesions and showed an enhanced immunosuppressive capacity. This MDSC accumulation was associated with a strong TCR ζ-chain downregulation in T cells suggesting that the tumor inflammatory microenvironment supports MDSC recruitment and immunosuppressive activity. Indeed, upon administration of phosphodiesterase-5 inhibitor sildenafil or paclitaxel in non-cytotoxic doses, we observed reduced levels of chronic inflammatory mediators in association with decreased MDSC amounts and immunosuppressive function. This led to a partial restoration of ζ-chain expression in T cells and to a significantly increased survival of tumor-bearing mice. CD8 T-cell depletion resulted in an abrogation of beneficial outcome of both drugs, suggesting the involvement of MDSC and CD8 T cells in the observed therapeutic effects. Our data imply that inhibition of chronic inflammation in the tumor microenvironment should be applied in conjunction with melanoma immunotherapies to increase their efficacy.

Chronic inflammation promotes myeloid-derived suppressor cell activation blocking antitumor immunity in transgenic mouse melanoma model

Tumor microenvironment is characterized by chronic inflammation represented by infiltrating leukocytes and soluble mediators, which lead to a local and systemic immunosuppression associated with cancer progression. Here, we used the ret transgenic spontaneous murine melanoma model that mimics human melanoma. Skin tumors and metastatic lymph nodes showed increased levels of inflammatory factors such as IL-1β, GM-CSF, and IFN-γ, which correlated with tumor progression. Moreover, Gr1(+)CD11b(+) myeloid-derived suppressor cells (MDSCs), known to inhibit tumor reactive T cells, were enriched in melanoma lesions and lymphatic organs during tumor progression. MDSC infiltration was associated with a strong TCR ζ-chain down-regulation in all T cells. Coculturing normal splenocytes with tumor-derived MDSC induced a decreased T-cell proliferation and ζ-chain expression, verifying the MDSC immunosuppressive function and suggesting that the tumor inflammatory microenvironment supports MDSC recruitment and immunosuppressive activity. Indeed, upon manipulation of the melanoma microenvironment with the phosphodiesterase-5 inhibitor sildenafil, we observed reduced levels of numerous inflammatory mediators (e.g., IL-1β, IL-6, VEGF, S100A9) in association with decreased MDSC amounts and immunosuppressive function, indicating an antiinflammatory effect of sildenafil. This led to a partial restoration of ζ-chain expression in T cells and to a significantly increased survival of tumor-bearing mice. CD8 T-cell depletion resulted in an abrogation of sildenafil beneficial outcome, suggesting the involvement of MDSC and CD8 T cells in the observed therapeutic effects. Our data imply that inhibition of chronic inflammation in the tumor microenvironment should be applied in conjunction with melanoma immunotherapies to increase their efficacy.

Lymphocyte recruitment into the tumor site is altered in patients with MSI-H colon cancer

The ability of the host to mount an appropriate immune response to aberrant cells is one factor that determines prognosis in cancer patients. Naturally occurring regulatory T cells (T regs; CD4+ CD25+ cells) are key regulators of peripheral tolerance. It has been suggested that high levels of T regs are detrimental to the patient in some forms of cancer, but the role of these antigen-specific cells in individuals with colorectal cancers with high levels of microsatellite instability is unknown. Herein, we examined the ability of individuals with MSI-H or microsatellite stable colon cancer to recruit lymphocytes to the tumor site. Immunohistochemical staining was performed on archived paraffin-embedded specimens from a total of 38 individuals with MSI-H (n = 25) or MSS (n = 13) colon cancers to determine the proportion of CD3+, CD8+ and CD25+ cells infiltrating the tumor site. Patients with MSI-H colon cancers had increased percentages of CD8+ TILs (cytotoxic T cells) as compared to individuals with MSS colon cancer (47.3 vs. 24.04% of the infiltrate CD8+, respectively). No differences in the levels of CD25+ T cells were observed between individuals with MSI-H colon cancers and MSS colon cancers (0.53 vs. 0.54% CD25+, respectively). Together, these data suggest that the survival advantage enjoyed by patients with MSI-H colorectal cancer may, in part, be attributed to the increased cytolytic response, but not to an antigen-specific immunosuppressive response in MSS patients.

Tumor-associated macrophages and CD3-zeta expression of tumor-infiltrating lymphocytes in human esophageal squamous-cell carcinoma

The clinical significance of tumor-associated macrophages (TAMs) and CD3-zeta chain expression of tumor-infiltrating lymphocytes (TILs), and their correlation in human esophageal squamous cell carcinoma (SCC) are not very clear. Serial histological slides from 137 esophageal SCC patients who had undergone tumor resection were immunohistochemically studied with anti-CD68, anti-CD3-zeta and anti-CD3-epsilon antibodies. TAMs infiltration (expressed as macrophage index, M(phi)I) and CD3-zeta expression (judged by Z/E = CD3-zeta+ cells/CD3-epsilon+ cells ratio) in different tissue compartments were observed. We found that the total tumor tissue region had significantly higher macrophage density and lower CD3-zeta expression (mean +/- SD: M(phi)I(normal): 225.3 +/- 85.9; Z/E(total): 0.52 +/- 0.25; n = 137) relative to adjacent histologically normal esophageal squamous epithelium (M(phi)I(normal): 60.5 +/- 31.7, P < 0.001; Z/E(normal): 0.79 +/- 0.35, P = 0.001; n = 70). Significantly higher M(phi)I(stroma) (P = 0.006) and lower Z/E(total) (P = 0.016) were detected in patients with lymph node metastasis than in those without. Patients with high M(phi)I(total) and M(phi)I(cancer) but low Z/E(total) had poorer surgical outcomes. Univariate analysis of M(phi)I(total) and multivariate analysis of M(phi)I(total) with specific clinico-pathological parameters demonstrated M(phi)I(total) to be an independent prognostic factor for survival in esophageal SCC patients (Cox proportional hazard model, P = 0.029 and P = 0.031, respectively).

Primary tumor cells resected from cancer patients and decorated with a novel form of CD80 protein serve as effective antigen-presenting cells for the induction of autologous T cell immune responses ex vivo

Vaccination with autologous tumor cells genetically modified to express costimulatory molecules has shown utility for cancer immunotherapy in preclinical and limited clinical settings. Given the complicated nature of gene therapy, a practical alternative approach has been designed that relies on modification of the cell membrane with biotin and its "decoration" with a chimeric protein composed of the functional portion of human CD80 and core streptavidin (CD80-SA). We tested whether primary tumor cells resected from cancer patients can be decorated with CD80-SA and whether such cells serve as antigen-presenting cells (APCs) to generate autologous T cell responses ex vivo. Tumors and peripheral blood lymphocytes (PBLs) were collected from 14 lung, 9 colon, and 2 breast "treatment-naive" cancer patients presenting various clinical stages of the disease. Tumors were mechanically processed, irradiated, decorated with CD80-SA or control streptavidin (SA) protein, and used as APCs in ex vivo autologous T cell-proliferative and cytotoxicity assays. All tumor samples were modified with CD80-SA, albeit with various degrees of decoration ranging from 21.8 to 100%. CD80- SA-decorated cells generated significant proliferative responses in autologous T cells from 9 of 16 evaluable patients (p < 0.05). Proliferative responses were CD80-SA specific and heterogeneous, with stimulation indices ranging from 0.25 to 45. In 15 of 15 evaluable patients, CD80-SA-specific cytotoxic T cell responses against autologous tumors were generated, 11 of which were significant, with specific killing ranging from 5 to 70%. Taken together, these data demonstrate that primary tumor cells can be effectively decorated with CD80-SA and that such cells serve as APCs to induce autologous antitumor T cell responses.

HSP-10 in ovarian cancer: expression and suppression of T-cell signaling

OBJECTIVE

Suppressed T-cell activation is a hallmark of advanced ovarian cancer. Studies in pregnancy have demonstrated similar T-cell dysfunction mediated, at least in part, by HSP10, identified as "early pregnancy factor." This pilot study addresses the presence of HSP10 in the circulation of ovarian cancer patients and assesses its role in suppressing CD3-zeta.

METHODS

Sera were obtained from ovarian cancer patients (n = 10) and age-matched noncancer-bearing female controls (n = 9). HSP10 presence was determined semiquantitatively by Western immunoblotting in sera, ascites, and ovarian tumor cell conditioned media. The consequences of HSP10 on CD3-zeta suppression were defined using a Jurkat cell bioassay, using unfractionated patient sera, sera with HSP10 removed by immunoprecipitation and the immunoprecipitate.

RESULTS

HSP10 was detected in both sera and ascites of patients with ovarian cancer; however, it was not detectable in controls. HSP10 was also detected in the culture media of ovarian tumor cells. Sera containing HSP10 suppressed T-cell CD3-zeta expression, which correlated with HSP10 levels (r2 = 0.839). When HSP10 was removed from the sera, the ability to suppress CD3-zeta was diminished and the immunoprecipitated material was capable of suppressing CD3-zeta.

CONCLUSIONS

HSP10 appears to be produced and released from ovarian tumor cells and is detectable in the peripheral blood and ascites of patients. This circulating HSP10 appears to suppress T-cell expression of CD3-zeta, a key component of T-cell activation. Our findings indicate that, as in pregnancy, production and release of HSP10 may be a critical factor in the suppression of T-cell activation, allowing the tumor to escape immune surveillance.

Strong HLA-DR antigen expression on cancer cells relates to better prognosis of colorectal cancer patients: Possible involvement of c-myc suppression by interferon-gamma in situ

Strong HLA-DR antigen expression on cancer cells relates to better prognosis of colorectal cancer patients, although the precise mechanism is controversial. From an immunological point of view, HLA-DR antigen, induced by interferon (IFN)-gamma, is required for tumor-associated antigen recognition by CD4(+) T cells. For instance, as reported previously, the expression of HLA-DR antigen in normal colorectal epithelium immediately adjacent to cancer coincided significantly with the existence of IFN-gamma mRNA in the tissue. From another aspect, IFN-gamma has been revealed to suppress c-myc expression in vivo through a stat1-dependent mechanism, which is important for cell growth, cell cycle and chromosome instability. In the present study, strong HLA-DR-positive expression on cancer cells was significantly related to better prognosis for colorectal cancer patients. High IFN-gamma mRNA expression in situ indicated significantly less activation of c-myc mRNA expression. Further, HLA-DR antigen expression in cancer cells, as well as Dukes stages, was an independent factor for better long-term survival by multivariate analysis. Taken together, IFN-gamma, which induces HLA-DR antigens on the cell surface, also suppresses c-myc expression in situ, and is a possible non-immunological mechanism involved in the better long-term survival of colorectal cancer patients.

Masking of the CD3 gamma di-leucine-based motif by zeta is required for efficient T-cell receptor expression

The T-cell receptor (TCR) is a multimeric receptor composed of the Ti alpha beta heterodimer and the noncovalently associated CD3 gamma delta epsilon and zeta(2) chains. All of the TCR chains are required for efficient cell surface expression of the TCR. Previous studies on chimeric molecules containing the di-leucine-based endocytosis motif of the TCR subunit CD3 gamma have indicated that the zeta chain can mask this motif. In this study, we show that successive truncations of the cytoplasmic tail of zeta led to reduced surface expression levels of completely assembled TCR complexes. The reduced TCR expression levels were caused by an increase in the TCR endocytic rate constant in combination with an unaffected exocytic rate constant. Furthermore, the TCR degradation rate constant was increased in cells with truncated zeta. Introduction of a CD3 gamma chain with a disrupted di-leucine-based endocytosis motif partially restored TCR expression in cells with truncated zeta chains, indicating that the zeta chain masks the endocytosis motif in CD3 gamma and thereby stabilizes TCR cell surface expression.

Workshop on Cancer Biometrics: Identifying Biomarkers and Surrogates of Cancer in Patients

The current excitement about molecular targeted therapies has driven much of the recent dialog in cancer diagnosis and treatment. Particularly in the biologic therapy of cancer, identifiable antigenic T-cell targets restricted by MHC molecules and the related novel stress molecules such as MICA/B and Letal allow a degree of precision previously unknown in cancer therapy. We have previously held workshops on immunologic monitoring and angiogenesis monitoring. This workshop was designed to discuss the state of the art in identification of biomarkers and surrogates of tumor in patients with cancer, with particular emphasis on assays within the blood and tumor. We distinguish this from immunologic monitoring in the sense that it is primarily a measure of the tumor burden as opposed to the immune response to it. Recommendations for intensive investigation and targeted funding to enable such strategies were developed in seven areas: genomic analysis; detection of molecular markers in peripheral blood and lymph node by tumor capture and RT-PCR; serum, plasma, and tumor proteomics; immune polymorphisms; high content screening using flow and imaging cytometry; immunohistochemistry and tissue microarrays; and assessment of immune infiltrate and necrosis in tumors. Concrete recommendations for current application and enabling further development in cancer biometrics are summarized. This will allow a more informed, rapid, and accurate assessment of novel cancer therapies.

T-cell activation marker expression on tumor-infiltrating lymphocytes as prognostic factor in cutaneous malignant melanoma

The central role of T cells in antitumor immunity is well established. However, tumor progression, often seen in the presence of substantial lymphocytic infiltration, suggests that these T cells are not capable of mounting an effective immune response to control tumor growth. Evidence has accumulated that T lymphocytes infiltrating human neoplasms are functionally defective, incompletely activated, or anergic. Therefore, when characterizing the immune competent cells within lymphoid infiltrates of tumors, it is important to assess their activation state. We investigated the expression of two T-cell activation markers, interleukin 2 receptor alpha (CD25) and OX40 (CD134), by immunohistochemistry in primary cutaneous melanoma samples of 76 patients and analyzed it in relation to tumor stage and tumor progression (>5 years follow-up), as well as to patients' survival. We found that the degree of infiltration by CD25(+) and intratumoral OX40(+) lymphocytes showed a tendency to decrease in thicker melanomas. The frequency of samples with high numbers of peritumoral CD25(+) and OX40(+) cells was significantly lower (P = 0.0009 and P = 0.0087, respectively) in melanomas developing distant visceral metastases, compared with nonmetastatic or lymph node metastatic tumors. For both activation markers studied, high peritumoral densities were associated with longer survival by univariate analysis (P = 0.0028 and P = 0.0255 for CD25 and OX40, respectively), whereas peritumoral OX40(+) lymphocyte infiltration had an impact on survival also in multivariate analysis (P = 0.035). The results suggest that the presence of lymphocytes expressing the T-cell activation markers CD25 or OX40 shows correlation with tumor progression as well as with patients' survival in cutaneous malignant melanoma.

Modulation of CD3-zeta as a marker of clinical response to IL-2 therapy in ovarian cancer patients

OBJECTIVE

In women with advanced ovarian cancer, levels of CD3-zeta on peripheral blood lymphocytes have previously been demonstrated to correlate with responsiveness to interleukin (IL)-2 therapy. The aims of this study were to identify the circulating component that modulated zeta expression and to define whether this suppressive activity could serve as a marker of biotherapy responsiveness.

METHODS

Sera were obtained from 17 patients with advanced ovarian cancer treated with intraperitoneal IL-2 in a phase I trial between 1987 and 1990. Nine of these patients exhibited a clinical response, while eight did not respond. Six additional sera from age-matched, noncancer-bearing women were used as controls. Jurkat E6-1 cells were used to assay modulation of CD3-zeta by sera and serum-derived components. Jurkat cells were exposed to serum or chromatographically fractionated serum components for 4 days and zeta expression was analyzed by Western immunoblots and quantitated by densitometry.

RESULTS

The effect of sera on zeta expression was compared between responders and nonresponders. Incubation of Jurkat cells with sera from responders suppressed CD3-zeta expression by 36.7% (vs. control treated), while treatment with sera from nonresponders produced an 83.7% reduction in zeta expression (difference between groups, P < 0.001). When sera from nonresponders were chromatographically fractionated, a <20 kDa component was identified that correlated with decreased zeta chain expression. This component was diminished in the sera of responders and absence in controls.

CONCLUSIONS

Thus, in patients with advanced ovarian cancer, a circulating component, which decreases zeta expression, can be identified as a marker for responsiveness to IL-2 therapy.

Infiltration of antitumor immunocytes into the sentinel node in gastric cancer

The sentinel node (SN) is regarded as the first drainage lymph node, and tumor cells are considered likely to directly affect the SN. However, few reports have identified differences between SNs and non-SNs in cancer patients. Subjects in this study included 27 patients with gastric cancer who underwent curative operation and intraoperative detection of SNs by radioisotope methods. The mean number of SNs was 3.2 (range 1 to 5). Degree of infiltration of natural killer cells, dendritic cells, MIB-1 labeling index, and CD3-zeta expression of lymphocytes in SNs and non-SNs were examined by means of immunohistochemical methods. Degree of infiltration was compared according to depth of invasion and between SNs and non-SNs. Patients with early-stage cancer displayed a greater degree of infiltration of MIB-1 labeling index and CD3-zeta expression than patients with pT2 or pT3 lesions (P<0.05). The MIB-1 labeling index in SNs was significantly lower than that in non-SNs (P<0.05). However, no significant difference was observed in infiltration of natural killer cells, dendritic cells, or CD3-zeta. Morphologic changes of dendritic cells in SNs were not definite. Our results suggest that SNs in gastric cancer might not be suppressed, unlike in breast cancer and melanoma. SN paralysis may depend on tumor- and organ-specific characteristics or exogenous stimulation from the gastric mucosa. Studies in progress will help to identify immunologic paralysis of the SN in various types of cancer. Attention must therefore be paid to organ specificity.

Expression of zeta in T cells prior to interleukin-2 therapy as a predictor of response and survival in patients with ovarian carcinoma

Expression levels of T-cell receptor (TcR)-associated zeta chain were reported to reflect functional competence of T lymphocytes in patients with cancer. This retrospective study was performed to evaluate zeta chain expression in circulating T cells obtained from clinical responders and nonresponders among 19 patients with advanced ovarian carcinoma treated with intraperitoneal interleukin-2 (IL-2) biotherapy. Banked lymphocytes, which were collected from the patients who participated in a phase I clinical trial performed between 1987 and 1990, were used for quantitative flow cytometry to measure zeta-chain expression in T lymphocytes prior to and at the end of therapy. The data were correlated with 7-year survival. The patients (9 responders and 10 nonresponders) were stratified into two groups based on zeta chain expression in CD3+ T cells above or below the mean. Patients with lower zeta expression in circulating T cells had shorter survival compared to patients whose T cells expressed high zeta. Pretherapy zeta expression was significantly lower (p = 0.03) in CD8+T cells of nonresponders than in CD8+T cells of normal controls. In patients with advanced ovarian carcinoma, low expression of the zeta chain in peripheral blood T cells prior to biotherapy might both reflect a large tumor burden and predict a poor of response to IL-2 bio-therapy.