To Tumor-infiltrating Lymphocytes Research Articles

Genomic investigation of co-targeting tumor immune microenvironment and immune checkpoints in pan-cancer immunotherapy

Drugs that target immune checkpoints (ICPs) have become the most popular weapons in cancer immunotherapy; however, they are only beneficial for a small fraction of patients. Accumulating evidence suggests that the tumor immune microenvironment (TIME) plays a critical role in anti-cancer immunity. This study aimed to assess the potential merits and feasibility of combinational targeting ICPs and TIME in cancer immunotherapy. A total of 31 cancer type-specific datasets in TCGA were individually collected by the publicly available web servers for multiple bioinformatic analyses of ICPs and TIME factors. GEPIA was used to calculate the prognostic indexes, STRING was used to construct protein–protein interactions, cBioPortal was used for visualization and comparison of genetic alterations, and TISIDB was used to explore the correlation to tumor-infiltrating lymphocytes (TILs). Intriguingly, TIME factors were identified to have more global coverage and prognostic significance across multiple cancer types compared with ICPs, thus offering more general targetability in clinical therapy. Moreover, TIME factors showed interactive potential with ICPs, and genomic alteration of TIME factors coupled with that of ICPs, at least in pancreatic cancer. Furthermore, TIME factors were found to be significantly associated with TILs, including but not limited to pancreatic cancer. Finally, the clinical significance and translational potential of further combination therapies that incorporate both ICP inhibitors and TIME factor-targeted treatments were discussed. Together, TIME factors are promising immunotherapeutic targets, and a combination strategy of TIME factors-targeted therapies with ICP inhibitors may benefit more cancer patients in the future.

Characterization of the immune microenvironment in malignant pleural mesothelioma reveals prognostic subgroups of patients

Malignant pleural mesothelioma (MPM) is a rare tumor with an extremely poor prognosis. Its pathogenesis is related to an immune response against asbestos fibers. The T-lymphocytes, including CD8POS and CD4POS cells, are an important part of the MPM immune microenvironment, and likely contribute to the therapy resistance observed in these tumors. Here, we sought to characterize the MPM-specific lymphocytes subpopulations within the tumor immune microenvironment to identify novel clinically relevant immunologic subtypes of tumors. Representative formalin-fixed, paraffin-embedded (FFPE) tissue blocks of 88 MPMs were included in tissue microarrays and subjected to tumor-infiltrating lymphocytes (TILs) quantification and subtyping by immunohistochemistry (IHC) with antibodies specific for CD4, CD8, and CD19. Further, PD-L1 (clone 22C3) expression was assessed by IHC as a combined positive score (CPS). Our data show that PD-L1 expression by tumor cells or the presence of a sarcomatoid component is related to increased stromal TILs presence in MPM. Survival analyses showed that low CD4POS and high CD8POS stromal TILs are associated with poor patients’ survival. In MPMs with PD-L1 CPS > 1, stromal CD8HIGH was a poor prognostic factor, akin stromal CD4POS peritumoral TILs correlated with a worse prognosis. Furthermore, we demonstrated that a high CD4POS/CD8POS ratio in the tumor immune microenvironment is an independent prognostic factor for survival. Finally, we provided evidence that the characterization of the stromal immune landscape of MPM predicts responses to chemotherapy in subgroups of MPM. The results of this study provide novel insights into the clinical scenario of immune-related biomarkers in MPM.

Local and Systemic Inflammatory Markers as Prognostic and Predictive Markers In Locally Advanced Triple Negative Breast Cancer

Local inflammatory markers have been defined as prognostic and predictive markers in triple negative markers as proved by many studies. The prognostic and predictive value of systemic inflammatory markers such as neutrophil lymphocyte ratio (NLR) and lymphocyte monocyte ratio (LMR) remain to be elucidated. Aim of study: To evaluate pathological complete response (PCR) to neoadjuvant chemotherapy in locally advanced cancer breast in relation to tumor infiltrating lymphocytes(TILs), neutrophil lymphocyte ratio and lymphocyte monocyte ratio as well as overall survival and disease free survival. Patients and methods: In Tanta university Hospital, oncology department form January 2012 to December 2013, 67 patients with locally advanced TNBC stage IIB, IIIB 0r IIIC using TNM 8t h edition . All patients received neoadjuvant chemotherapy in the form of dose dense AC followed by paclitaxel (adriamycin & cyclophosphamide 60 mgm/m2 & 600 mgm/m2 respectively the cycle is repeated every 2 weeks for 4 cycles followed by paclitaxel 175mgm/m2 every 2 weeks for 4 cycles). All cycles with G-CSF support. Pre treatment TILs, NLR and LMR were evaluated with PCR and as prognostic factor of survival. Results: Low NLR has been detected in 74.6% of cases and has been associated with high TILs and this was statistically significant (p value=0.03). High LMR was observed in 80.6% of cases and correlated significantly with TILs (p value =0.003). Pathological CR was found to be associated with high TILs, low NLR and high LMR. In our study we evaluated the pre neoadjuvant systemic and local inflammatory markers as prognostic marker we found that in multivariate analysis, the lymphocyte monocyte ratio maintained their statistical significance with overall survival. While tumor infiltrating lymphocyte maintained their statistical significance as prognostic factors with overall survival and disease free survival. Conclusion: Systemic inflammatory markers can be used as marker of pathological complete response in locally advanced triple negative breast6 cancer with neoadjuvant chemotherapy.

Head-to-head comparison of in-house produced CD19 CAR-T cell in ALL and NHL patients

BackgroundCD19 chimeric antigen receptor T (CAR-T) cells demonstrate remarkable remission rates in pediatric and adult patients with refractory or relapsed (r/r) acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). In...

PD-L1 expression and survival in p16-negative and -positive squamous\xa0cell carcinomas of the vulva

AimProgrammed death-ligand 1 (PD-L1) has become a widely used predictive biomarker for therapy with checkpoint inhibitors in a variety of cancers. Here, we studied the expression of PD-L1 in squamous cell carcinomas of the vulva (SCCV) with regard to HPV status via its surrogate marker p16. Additionally, the status of PD-L1 and p16 were analyzed for prognostic information and potential correlation to tumor-infiltrating lymphocytes (TILs).MethodsPD-L1 was analyzed in 128 cases of SCCV using the tumor proportion score (TPS), the immune cell score (ICS) and the combined positive score (CPS). Cases were immunostained for p16 and analyzed for stromal TILs. PD-L1, p16, and TILs were compared to clinico-pathological parameters and patient’s survival.ResultsTPS ≥ 50% and CPS ≥ 50 were correlated to a worse grading (p = 0.028 and p = 0.031), but not to FIGO-stage. CPS ≥ 50 was associated to a worse prognosis with overall survival (p = 0.021) but was not correlated to the progression-free survival. P16-positivity was correlated to a longer progression-free survival (p = 0.006) and overall survival (p = 0.023). PD-L1 expression was independent from p16 status. TILs ≥ 50% were present in 24% of the cases and were strongly correlated to PD-L1 (TPS p = 0.02, ICS p < 0.001, CPS p = 0.001).ConclusionOur data demonstrate that PD-L1 expression is frequent in SCCV and independent from p16 status. High PD-L1 expression was associated with an unfavorable outcome whereas p16-positivity turned out to be an independent positive prognostic factor.

Abstract 2714: Combination of monalizumab and durvalumab as a potent immunotherapy treatment for solid human cancers

Abstract Inhibitory CD94-NKG2A (Natural Killer Group 2A) receptors are expressed on subsets of natural killer (NK) cells, γδ and CD8+ T cells. HLA-E (Human Leukocytes Antigen-E), the ligand for CD94-NKG2A, is upregulated on cancer cells of several solid tumors, providing a negative regulatory signal to tumor-infiltrating lymphocytes (TILs). Blockade of this immune checkpoint pathway with anti-NKG2A monoclonal antibodies (Ab) enhances NK cell responses to tumor cells in vitro and in humanized mice. Here, we describe NK and CD8+ T cell infiltrates in several human solid tumors by immunohistochemistry (IHC) and multicolor flow cytometry. We then studied the effects of in vitro targeting both pathways on primary human NK and CD8+ T cells. By using IHC on formalin-fixed paraffin-embedded samples on cohorts of solid tumors i.e. non-small cell lung cancer (NSCLC, n=45), stomach tumor (n=76), colorectal cancer (CRC, n=103), head and neck tumor (HNSCC, n=68), pancreatic tumors (n=77) and renal cell carcinoma (RCC, n=75), we observed NKp46+ NK cells in the large majority of cancer types (especially in RCC, HNSCC and stomach cancers). CD8+ T cells were found at significantly higher densities in all tumor types. In another cohort of HNSCC samples (n=60), higher proportions of CD94+ lymphocytes were found within the tumor islets both in the primary tumors and in the metastatic lymph nodes. In addition, in CRC patients with liver metastasis (n=101), high CD94+ cell densities were associated with poor overall survival. These data suggest that NKG2A blockade might unleash NK and T cells that are present in close contact to tumor cells. As previously shown, we confirmed that CD94-NKG2A ligand, HLA-E, was expressed by tumor cells in the large majority of solid tumor. In addition, high PD-L1 expressions were observed in NSCLC, stomach tumors, CRC and HNSCC. Flow cytometry analyses revealed that NK and CD8+ T cells co-expressing NKG2A and PD-1 were more numerous in tumor compared to matched peripheral blood and adjacent tissues of NSCLC and HNSCC patients. To mimic the “NKG2A+PD-1+” TILs phenotype, chronic stimulation of peripheral blood cells from healthy volunteers was performed using IL-15. The conditions led to the induction of NKG2A and PD-1 on NK and antigen-specific CD8+ T cell subsets. These effector cells were then co-cultured with tumor cell lines expressing HLA-E +/- PD-L1. We showed that monalizumab, a first-in class anti-NKG2A Ab, combined with durvalumab resulted in higher responses (CD107 mobilization and IFN-γ production) compared to each Ab alone. These data were confirmed in a syngeneic mouse model where both NK and CD8+ T cells were found to be involved in tumor rejection. Together, these data confirm that blocking NKG2A can potentiate the anti-tumor efficacy of PD-1 inhibitors and support the rationale for ongoing clinical trials investigating the monalizumab/durvalumab combination (NCT02671435 and NCT03088059). Citation Format: Caroline Soulas, Romain Remark, Vedran Brezar, Julie Lopez, Elodie Bonnet, Flavien Caraguel, Ana Lalanne, Caroline Hoffmann, Caroline Denis, Thomas Arnoux, Clarisse Caillet, Arnaud Dujardin, Guillaume Habif, Olivier Lantz, Cécile Bonnafous, Eric Vivier, Pascale Andre. Combination of monalizumab and durvalumab as a potent immunotherapy treatment for solid human cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2714.

The prognostic impact of neutrophil to lymphocyte ratio in patients with recurrent or metastatic esophageal squamous cell carcinoma receiving immune checkpoint inhibitors.

69 Background: The study explored the prognostic impacts of clinical parameters including neutrophil to lymphocyte ratio (NLR) in recurrent/metastatic esophageal squamous cell carcinoma (R/M ESCC) patients receiving anti-programmed cell death protein-1 (PD-1)/PD ligand 1 (PD-L1)-based therapy. Methods: Thirty-eight patients were enrolled. Tumor response evaluation was made according to Response Evaluation Criteria in Solid Tumours 1.1, and the clinical benefit response (CBR) was defined as complete response, partial response or stable disease at least 6 months. Clinical factors were analyzed for their impacts on patients' overall survival (OS) and progression-free survival (PFS). Formalin-fixed, paraffin-embedded tissues from 8 patients were analyzed by NanoString nCounter Human PanCancer Immune Profiling (NanoString Technologies, Seattle, WA, US). Results: Twenty-six recurrent and 12 de novo metastatic ESCC patients were enrolled. The response rate is 11.8%, and the CBR rate was 21.1%. The median PFS and OS are 2.7 and 5.5 months, respectively. The CBR group has lower blood white blood cells (WBC) ( P = 0.029), monocytes (p = 0.003), and NLR (p = 0.005). In univariate analysis, WBC, neutrophils, and NLR were statistically associated with PFS; performance status (PS), disease extent, albumin, WBC, neutrophils, and NLR were statistically associated with OS. In multivariate analysis, NLR (p = 0.007) was statistically associated with PFS; PS (p = 0.029) and NLR (p = 0.050) were statistically associated with OS. On examining the immune-related genes in ESCC tissues’ microenvironment, the ratios of mast cells, neutrophils, and macrophages relative to tumor-infiltrating lymphocytes (TILs) have significantly lower in the CBR group than in the non-CBR group. Conclusions: High NLR was associated with inferior prognosis in R/M ESCC patients receiving anti-PD-1/PD-L1-based therapy. The increased ratio of neutrophil to TILs in the ESCC tumor microenvironment of non-CBR patients may suggest a mechanistic role of neutrophils in affecting the efficacy of anti-PD-1/PD-L1 therapy. (Supported by the grant of MOST 105-2314-B-002 -186 -MY3)

Immune microenvironment in brain metastases of breast cancer.

1081 Background: In patients with brain metastasis (BM) of melanoma or lung cancer, significant activity of immune checkpoint inhibitors has been reported. However, details of the immune microenvironment in BM has not been unveiled. In this study, we used immunohistochemistry (IHC) to compare primary breast tumors and BM tumor samples with respect to tumor infiltrating lymphocytes (TILs) and tumor characteristics related to the immune system. Methods: We retrospectively identified 107 patients with breast cancer, diagnosed with BM, who had undergone surgery between 2001 and 2012 at 8 institutions. We collected 191 samples which included both BM samples alone and pair-matched samples (primary and BM). Hematoxylin and eosin (H&amp;E) stained slides were evaluated for stromal TILs in 10% increments (0–1%, &gt; 1– &lt; 10%, 10%–100%). IHC was performed using the following primary antibodies: CD4, CD8, Foxp3, PD-L1, PD-L2 and HLA class I. The cells positive for each antibody signal were counted automatically using ImageJ (NIH). The expression of PD-L1, PD-L2, and HLA on the tumor cells was scored as 0 (negative), 1 (weak or focal), or 2 (strong). Results: The median category of TILs of BM tumors was &gt; 1– &lt; 10% (range: 1–30%). Forty-six pair-matched samples were analyzed and the percentage of TILs in the primary breast tumor was significantly higher than that in BM samples (paired t-test, P &lt; 0.01). The number of CD4/CD8/Foxp3 positive cells in primary breast tumor was also significantly higher than in BM samples (paired t-test, P &lt; 0.05 for all categories). The negative/positive conversion occurred with the expression of HLA/PD-L2 on tumor cells (paired t-test, P = 0.03/0.06, respectively). No significant difference was observed in the overall survival (OS) of patients, from initial BM, based on high or low TILs (log-rank test, P = 0.131). However, triple negative breast cancer patients with low TILs had significantly shorter OS compared with patients with high TILs (log-rank test, P = 0.04). Conclusions: We demonstrated that TILs in BM tumors was significantly lower as compared to primary breast tumors. The expression of immune related molecules on tumor cells was converted in BM tumors.

Association of mesenchymal subtype with the presence of immune infiltrates in squamous cancer classifier.

e23073 Background: Lehmann and colleagues (Lehmann 2011) devised a classification system for triple negative breast cancer (TNBC) consisting of seven subtypes—IM, BL1, BL2, LAR, M, MSL, and UNS. Recent work has shown the IM group (characterized by the presence of immunomodulatory genes) is due to tumor infiltrating lymphocytes (TILs), and should be measured independently of the other subtypes. Furthermore, the m subtype (characterized by genes associated with epithelial-mesenchymal transition (EMT)) was shown to have a highly inverse relationship with the IM group (Lehmann 2016). We (Ring 2016) modified the original algorithm into a 101-gene algorithm that also confirmed this inverse relationship between IM and m signatures (Grigoriadis SABCS 2016). While this is a novel and interesting finding, we wanted to know whether this inverse relationship applies to other epithelial cell origin cancers such as squamous lung cancer. Methods: We downloaded gene expression data from 548 squamous cell lung cancers from the TCGA database, and applied the 101-gene TNBC algorithm to the lung cohort without optimization or adjustment. Results: Of the 548 samples, 389 (71%) were able to be classified by the 101-gene algorithm. Of these, 82 (21%) had an m phenotype. 128 patients (33%) were positive for the IM signature. The expected overlap of patients positive for both IM and m was 27 patients (7%). The observed overlap was 0 patients (chi-squared = 29; p &lt; 0.001). Conclusions: The unoptimized 101-gene TNBC algorithm validated the observation that gene expression signatures for IM and m are inversely correlated. While any attempt to apply a TNBC algorithm to squamous lung cancer would need careful optimization and validation, these data support that the inverse relationship noted in TNBC may transcend the tissue of origin.

Pathology of healing: what else might we look at?

Several aspects of the article by Morita et al. (Cancer Medicine 5:1607‐18, 2016), examining the spontaneous healing phenomenon with reference to tumor infiltrating lymphocytes (TILs), require clarification. The concept of “healing”, which can perhaps be more accurately termed “regressive change”, remains controversial due to a lack of concrete evidence. Since regressive change is characterized by fibrosis and lymphocytes, a cancer nest that appears to lack a distinct basement membrane, surrounded only by lymphocytes, as in Morita et al's Figure 2F, should be meticulously examined because the appearance may correspond to a tumor having just completed the process of invasion. In our experience, a layer of myoepithelial cells in such foci is often difficult to detect even with immunohistochemistry. Thus, we suggest evaluating the viability of cancer cells within the nest by employing several markers, such as Ki67 and apoptotic markers, to judge whether the tumor is intraductal. It might also be useful to compare cases with versus without regressive change to elucidate the biology of such tumors. For these reasons, a tumor, floating within a pool of TILs and lacking obvious fibrous bands, might be an interesting material to examine in future studies.

Abstract 4147: T cell targeted peptides for monitoring immune response in melanoma

Abstract Melanoma develops the ability to evade immune recognition through multiple mechanisms, despite being highly immunogenic. This is demonstrated by the effective and additive response checkpoint blockade therapies have had during combination clinical trials in melanoma [1]. While the results of these trials have been promising, large portions of patients do not respond to treatment [1,2]. Additionally, many responders take months to show a response using standard criteria. In order to monitor patient response and understand the limitations of immunotherapy, we performed phage display to discover peptides targeted to tumor infiltrating lymphocytes (TILs) in melanoma tumors. To improve phage library characterization, we developed a method to deep sequence phage with the Ilumina MiSeq platform. Phage screens using PhD7 library (NEB) performed on HUVECS and on TILs, naïve and effector T cells, and B cells harvested from mice. The phage libraries generated from these screens were deep sequenced using the Illumina MiSeq system. The sequencing data was analyzed with an efficient, custom MATLAB script, which arranges sequences by frequency determining peptide frequencies for each library. Peptide frequency was normalized to a reference library generated by amplifying an unscreened phage library. T cell screens were compared with B cell and endothelial cell screens in sequence frequency matrices. Top TIL targeting sequences were cloned into phage, and then fluorescently labeled along with insert-less control phage. Labeled phage were incubated with TILs, or effector T cells and analyzed for specificity using flow cytometry. Four phage clones were identified with at least four fold increased binding for TILs over effector T cells isolated from the spleen. Interestingly, only subsets of the TILs were bound by the targeted phage. We have identified and validated peptides that demonstrate specificity for CD8 TILs. These peptide sequences represent candidates for development into companion diagnostic imaging agents for use with checkpoint therapies. We are currently evaluating these peptides in an in vivo tumor model to further validate their specificity and to determine their biodistributions. Peptides that validate in vivo could be developed into useful imaging agents. After peptide sequences have been validated in vivo, we will determine the phage binding partner using a phage based pulldown. The peptide binding partners discovered through this approach will provide insight into the subset of TILs bound by the phage. [1] Wolchok, J. D. et al., N Engl J Med 2013; 369:122-133. [2] Drake, CG. et al., Clin Cancer Res November 15, 201117. Citation Format: Dustin Bauknight, Andrew Buckner, Lindsey Brinton, Timothy Bullock, Kimberly Kelly. T cell targeted peptides for monitoring immune response in melanoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4147.

PD-L1 expression is associated with tumor-infiltrating T cells and favorable prognosis in high-grade serous ovarian cancer

ObjectiveAs a negative regulator of T cells, Programmed Death Ligand 1 (PD-L1) is both an indicator and inhibitor of anti-tumor immune responses, which has led to confusion about its prognostic significance. We investigated the primary source of PD-L1 expression in epithelial ovarian cancer and its relationship to tumor-infiltrating lymphocytes (TIL) and associated gene products. MethodsTissue microarrays containing high-grade serous carcinomas (HGSC) and endometrioid, clear cell and mucinous ovarian cancers from optimally debulked patients were assessed by immunohistochemistry for expression of PD-L1 and other markers (CD68, CD3, CD8, PD-1, CD103, FoxP3 and CD25). The Cancer Genome Atlas was interrogated for associations between PD-L1 expression and immune-related transcriptional and genomic features of HGSC. ResultsPD-L1 was primarily expressed by tumor-associated CD68+ macrophages rather than tumor cells. PD-L1+ cells frequently co-localized with CD8, CD4 and PD-1+ TIL, CD25+FoxP3+ Tregs, and other TIL subsets. PD-L1+ cells were prognostically favorable in HGSC. Moreover, the presence of both PD-L1+ cells and CD8 TIL was associated with better prognosis than CD8 TIL alone. PD-L1 gene expression was independent of BRCA status. At the transcriptional level, PD-L1 was associated with both cytolytic (granzyme B, T-bet and IFN-γ) and suppressive (PD-1, CTLA-4, LAG3 and IDO-1) gene products. ConclusionsPD-L1 is primarily expressed by macrophages in ovarian cancer and is strongly associated with both cytolytic and regulatory TIL subsets, resulting in a net positive association with survival. Tumors containing PD-L1+ macrophages appear caught in an immunological stalemate that may require multi-pronged immunotherapy to alleviate.

Perioperative Cimetidine Administration Improves Systematic Immune Response and Tumor Infiltrating Lymphocytes in Patients with Colorectal Cancer

Cimetidine has been shown to play an important role in the treatment of cancer and the regulation of the immune system. Therefore, we aimed to observe the effects of cimetidine on the systematic immune response in the perioperative period. Sixty patients with colorectal cancer were enrolled from Jan 2005 to Dec 2005 from Taizhou Hospital. The patients were administrated with cimetidine (0.8 g.d-1 or 1.2 g.d-1) or saline from the day of admission to the 10th POD. Venous blood sample was collected and the T-, B- and NK-lymphocyte subsets were determined by flow cytometry. The specimens were subjected to tumor-infiltrating lymphocytes (TILs) response examination. The levels of CD3 and CD4 T-lymphocytes were increased significantly in both low and high dose cimetidine groups 10 days after operation. The number of CD19 B cells was also elevated by cimetidine. However, no significant changes were observed in the CD8, CD4/CD8 value. TIL responses in the cimetidine groups were also enhanced significantly. Cimetidine can alleviate systematic immunosuppression and improve the local immune function of the colorectal cancer patients in the perioperative period.

Heat shock protein induced TCR γδ gene rearrangements in patients with oral cancer

We analyzed the T cell receptor (TCR) gammadelta gene repertoire in peripheral blood and tumor compartment of oral cancer (OC) patients before and after stimulation with heat shock proteins (hsp), which are known ligands for gammadelta T cells. Clonal TCR gamma and delta gene rearrangements in lymphocytes from tumor compartment and peripheral blood were studied using TCR Vgamma and Vdelta gene primers in PCR followed by heteroduplex analysis. Vgamma gene segments derived from VgammaI or VgammaII gene families were most dominantly expressed in peripheral blood lymphocytes (PBL) as compared to tumor infiltrating lymphocytes (TIL) of OC patients. Of the rearranged TCR delta alleles Vdelta1-Jdelta1 and Vdelta2-Jdelta1 gene rearrangements were the most predominant in PBL and TIL of OC patients respectively. Stimulation of gammadelta T cells with hsp 60/70 demonstrated a selective clonal expansion of Vgamma9-Vdelta2 (VgammaII family) subset indicating that, this expanded population of cells could be responsible for eliciting an immune response against oral tumor cells.

Cisplatin modulates tumor cell susceptibility to tumor-infiltrating lymphocytes in vivo

We investigated the in vivo augmentation of susceptibility of tumor cells to tumor-infiltrating lymphocytes (TILs) with cisplatin (CDDP). TILs showed cytotoxicity against autologous and established tumor cells. Pretreatment of tumor cells with CDDP 2 mu g/ml for 12 h enhanced the susceptibility of tumor cells to TILs in vitro. TILs and autologous tumor cells were obtained from malignant ascites of patients, before and after the intraperitoneal administration of CDDP. TILs had higher cytotoxicity against autologous tumor cells of CDDP treated as compared to untreated control tumor cells, providing direct evidence of in vivo immunomodulatory effect of CDDP in cancer patients.

Enhancement of tumor cell susceptibility to tumor-infiltrating lymphocytes by cisplatin.

Some means of enhancing the susceptibility of tumor cells to tumor-infiltrating lymphocytes (TIL) are required in adoptive immunotherapy. This study was designed to investigate whether or not tumor cell lysis by TIL was enhanced by treatment of the tumor cells with cisplatin, and also to clarify the mechanism of cisplatin's action on tumor cells. Autologous tumor cells and established cancer cell lines, including KATO-III and MKN-28, were used. Cytotoxic activities of TIL, the surface antigens of tumor cells, conjugation of TIL and tumor cells, and the production of TNF alpha from TIL were analyzed. Tumor cells treated with 2 micrograms/ml cisplatin for 12 h in vitro were more susceptible to bulk-cultured TIL and TIL clones. The surface antigens of tumor cells were not altered by the treatment with cisplatin. Cisplatin-treated tumor cells showed a higher binding ratio to TIL than did non-treated tumor cells. The anti-(tumor necrosis factor) (anti-TNF) or anti-TNF receptor antibody blocked the enhancement of cytotoxic activity by cisplatin. Thus, it was clarified that cisplatin enhanced the susceptibility of tumor cells to bulk-cultured TIL and TIL clones. Furthermore, the enhancement of cytotoxic activity by TIL in cisplatin-treated tumor cells was caused by a higher binding ratio to TIL and higher susceptibility to the TNF produced by TIL.

Effect of lentinan on lymphocyte subsets of peripheral blood, lymph nodes, and tumor tissues in patients with gastric cancer.

The effect of lentinan on lymphocyte subsets of peripheral blood, lymph nodes, and tumor tissues in gastric cancer patients was investigated. A 2-mg dose of lentinan was administered to 12 patients intravenously twice, the first at 3-9 days before and the second the day before surgery. The results were then compared with a control group without lentinan administration comprising 12 patients. Regarding peripheral blood and lymph nodes without metastasis, lymphocyte subsets defined with anti-CD3, anti-CD4, anti-CD8, anti-Leu7, and anti-Leu11 were analyzed by flow-cytometry. As for tumor tissues, lymphocyte subsets defined with anti-CD3, anti-CD4, anti-CD8, anti-Leu11, and anti-M3 were analyzed after immunohistochemical staining. There were no significant changes in the lymphocyte subsets of peripheral blood between the two groups. In the lymph nodes, the CD4 cell ratios increased; otherwise in regard to tumor-infiltrating lymphocytes (TILs), the number of CD4, Leu11 and LeuM3 cells showed a prominent increase. Therefore, lentinan was observed to produce different effects in accordance with the subjective organs.