Miguel Tallada

Coordinated downregulation of the antigen presentation machinery and HLA class I/β2-microglobulin complex is responsible for HLA-ABC loss in bladder cancer

Downregulation of MHC class I expression is a widespread phenomenon used by tumor cells to escape antitumor T‐cell‐mediated immune responses. These alterations may play a role in the clinical course of the disease. The aim of our study was to investigate the molecular mechanism underlying the absence of HLA‐class I molecule expression in bladder cancer cells. Microdissected tumor tissues were characterized by real‐time quantitative PCR for the expression of HLA‐ABC, β2‐microglobulin and the members of the antigen processing machinery (APM) of HLA class I molecules (LMP2, LMP7, TAP1, TAP2 and tapasin). Our results showed that irreversible HLA loss by mutations in the β2‐microglobulin gene was not the cause of low HLA class I expression in bladder cancers. In contrast, we observed a coordinated transcription downregulation of HLA‐ABC and β2‐microglobulin and APM genes in microdissected tumor tissue derived from bladder carcinomas. This mechanism may represent a major factor for the downregulation of HLA class I expression and in the subsequent direct recognition of cancer cells by cytolytic T lymphocytes. Because this regulatory mechanism is frequently reversible by IFN‐gamma treatment, we conclude that HLA class I expression should be a major consideration for immunotherapeutic purposes in patients with bladder cancer.

Genetic polymorphisms of RANTES, IL1-A, MCP-1 and TNF-A genes in patients with prostate cancer

BackgroundInflammation has been implicated as an etiological factor in several human cancers, including prostate cancer. Allelic variants of the genes involved in inflammatory pathways are logical candidates as genetic determinants of prostate cancer risk. The purpose of this study was to investigate whether single nucleotide polymorphisms of genes that lead to increased levels of pro-inflammatory cytokines and chemokines are associated with an increased prostate cancer risk.MethodsA case-control study design was used to test the association between prostate cancer risk and the polymorphisms TNF-A-308 A/G (rs 1800629), RANTES-403 G/A (rs 2107538), IL1-A-889 C/T (rs 1800587) and MCP-1 2518 G/A (rs 1024611) in 296 patients diagnosed with prostate cancer and in 311 healthy controls from the same area.ResultsDiagnosis of prostate cancer was significantly associated with TNF-A GA + AA genotype (OR, 1.61; 95% CI, 1.09–2.64) and RANTES GA + AA genotype (OR, 1.44; 95% CI, 1.09–2.38). A alleles in TNF-A and RANTES influenced prostate cancer susceptibility and acted independently of each other in these subjects. No epistatic effect was found for the combination of different polymorphisms studied. Finally, no overall association was found between prostate cancer risk and IL1-A or MCP-1 polymorphisms.ConclusionOur results and previously published findings on genes associated with innate immunity support the hypothesis that polymorphisms in proinflammatory genes may be important in prostate cancer development.

Analysis of NK cells and chemokine receptors in tumor infiltrating CD4 T lymphocytes in human renal carcinomas.

Recent data suggest that chemokines and chemokine receptors mediate leukocyte recruitment of all components of the antitumor response. This study aimed to phenotypically characterize the immune lymphocyte infiltrate in human renal cell carcinomas (RCCs) and at the invasive margin (tumor–host interface) and to define the association of these findings with established prognostic indicators. Tumor infiltrating lymphocytes (TILs) were obtained from 24 patients with RCC undergoing radical nephrectomy. Peripheral blood cells from 37 patients were also obtained before surgery. Our findings are consistent with the preferential recruitment of CD4+ Th1-polarized effector memory cells that express CXCR3/CCR5. These cells were the main component of TILs and expressed as CXCR3, CCR5, CD45RO, and CD95. Natural killer (NK) cells were found in significantly higher proportions in TILs of RCCs than in peripheral blood lymphocytes (PBLs) or in other tumors studied (colorectal and breast cancers), where these cells were found in small proportions. No differences in nuclear grade or other studied parameters were observed between the TILs and the lymphocytes present at the invasive margin, which showed a similar composition. However, differences were found according to the tumor stage. First, significantly fewer NK cells were observed in PBLs from metastatic patients. Second, a significantly lower proportion of CCR5/CXCR3/CD4+ cells and a higher proportion of CCR4/CD4+ cells were observed in metastatic patients, suggesting that preferential Th1-polarization may gradually change during the progression of renal cancer cells. Finally, the frequency of CD25/CD4+ cells was higher in metastatic patients. Although the sample of patients with metastasis was small, the overall results suggest a change in composition of the TILs that may potentially confer a selective advantage for tumor growth and may account for the suppression of an effective cytotoxic response.

Impact of interleukin-18 polymorphisms-607 and -137 on clinical characteristics of renal cell carcinoma patients

Current evidence suggests that chronic inflammation is associated with tumor development and progression. Interleukin-18 (IL-18) plays a central role in inflammation and the immune response, contributing to the pathogenesis and pathophysiology of infectious and inflammatory diseases. The objective of this study was to determine whether the presence of IL-18 polymorphisms -137 G/C (rs187238) and -607 A/C (rs1946518) was associated with size, grade, TNM stage, and survival in patients with renal cell carcinoma (RCC). The study cohort included 158 patients with RCC. Control group consisted of 506 samples from Spanish population. The studied IL-18 gene polymorphisms did not influence susceptibility to RCC in the analyzed group of patients (IL-18-607, p = 0.318; IL-18-137 p = 0.740) but may contribute to disease onset and aggressiveness. IL-18-607 CC genotype was significantly associated with higher tumor size (p = 0.001), grade (p = 0.030), T (p = 0.001), M (p = 0.012), and stage (p = 0.002). IL-18-103 GG genotype was correlated with higher tumor size (p = 0.036), grade (p = 0.017), T (p = 0.026), and stage (p = 0.011). The Cox proportional hazard model showed that nuclear grade and stage grouping were independent prognostic factors but IL-18 polymorphism was not. Polymorphism variants in the IL-18 gene (IL-18-607 and IL-18-137) may be associated with a worse prognosis for RCC. High levels of IL-18 production may play a major role in the growth, invasion and metastasis of renal cancer.

LOH at 6p21.3 region and HLA class I altered phenotypes in bladder carcinomas

Alterations in HLA class I antigen expression have been frequently described in different epithelial tumors and are thought to favor tumor immune escape from T lymphocyte recognition. Multiple molecular mechanisms are responsible for these altered HLA class I tumor phenotypes. Some are structural defects that produce unresponsiveness to treatment with interferons. Others include alterations in regulatory mechanisms that can be switched on by treatment of tumor cells with different cytokines. One important mechanism belonging to the first group is loss of heterozygosity (LOH) at chromosome region 6p21.3, which can lead to HLA haplotype loss. In this investigation, the frequency of LOH at 6p21 chromosome region was studied in 69 bladder carcinomas. Short tandem repeat analysis showed that 35% of cases had LOH in this chromosome region. By considering these results together with immunohistological findings previously published by our group, we identified a distribution pattern of HLA class I altered phenotypes in bladder cancer. The most frequently altered phenotype in bladder carcinomas was total loss of HLA class I expression (17 cases, 25%), followed by phenotype II associated with HLA haplotype loss (12 cases, 17.5%), and HLA allelic loss (ten cases, 14.5%). Nine cases (13%) were classified as having a compound phenotype, five cases (7%) as having HLA locus loss, and in 16 cases (23%) no alteration in HLA expression was detected. An important conclusion of this report is that a combination of different molecular and immunohistological techniques is required to precisely define which HLA alleles are lost during tumor progression and to characterize the underlying mechanisms of these losses. These studies should be performed when a cancer patient is to be included in an immunotherapy protocol that aims to stimulate different immune effector mechanisms.

A nucleotide insertion in exon 4 is responsible for the absence of expression of an HLA-A*0301 allele in a prostate carcinoma cell line

Keywords HLA · Null allele · Mutation · Microsatelliteinstability · TumorSerological typing methods have been used traditionallyto define the polymorphism of HLA antigens. However,since the introduction of DNA typing methods, discrep-ancies between serological and molecular methods havebeen reported. Thus, certain alleles type easily at theDNA level but lack cell surface expression and are,therefore, undetectable by serological typing. These dis-crepancies arise from structural differences between theexpressed and the deficient forms of the gene (Parham1997). In this report, based on a combination of cellularand molecular methods, we describe a nucleotide inser-tion responsible for the loss of expression of anHLA-A*0301 allele in a prostate carcinoma cell line.DU145 is a tumor cell line derived from a cerebralmetastasis of a prostate carcinoma. The cell line was ob-tained from the American Type Culture Collection(ATCC; Rockville, Md.). Molecular typing forHLAclass I (A and B loci) was performed on genomic DNAfrom the cell line using theHLA-Aand HLA-Bsequenc-ing-based typing kits and ABI PRISM 377 DNAMatch/Maker sequencer allele identification software(Applied Biosystems, Foster City, Calif.). TheHLA gen-otype from the DU145 cell line (sequences from exons 2and 3) wasHLA-A*0301, A*3303/HLA-B*5001,B*5701. HLA class I expression on the cell surface wasmeasured by indirect immunofluorescence using the ap-propriate anti-class I monoclonal antibody (mAb) andfluorescein isothiocyanate-labeled rabbit anti-mouse IgF(ab)

Higher HLA class I expression in renal cell carcinoma than in autologous normal tissue.

A total of 93 frozen primary renal cell carcinoma (RCC) samples and 31 frozen samples of corresponding normal renal tissue were analyzed for human leukocyte antigen (HLA) class I and HLA-DR expression. Unexpectedly, HLA class I expression was much higher on RCC cells than on normal renal tubular cells. Immunohistochemistry analysis of frozen and paraffin-embedded tissue samples, applying an extended panel of specific anti-HLA monoclonal antibodies, showed elevated HLA class I antigen expression in 95.6% of the tumors vs only 12.9% of normal renal tissues. These findings were confirmed by molecular analysis of HLA heavy chain and beta2-microglobulin (beta2m) transcription levels using quantitative real-time polymerase chain reaction (PCR) on microdissected tissue samples (isolated tumor nests and autologous normal renal tubules) from four patients. These results might help to explain the relatively high success rate of immunotherapy in patients with RCC. The molecular mechanism underlying the increased HLA class I expression in RCC has yet to be elucidated.

Open partial nephrectomy in renal cancer: a feasible gold standard technique in all hospitals.

Introduction. Partial nephrectomy (PN) is playing an increasingly important role in localized renal cell carcinoma (RCC) as a true alternative to radical nephrectomy. With the greater experience and expertise of surgical teams, it has become an alternative to radical nephrectomy in young patients when the tumor diameter is 4 cm or less in almost all hospitals since cancer-specific survival outcomes are similar to those obtained with radical nephrectomy. Materials and Methods. The authors comment on their own experience and review the literature, reporting current indications and outcomes including complications. The surgical technique of open partial nephrectomy is outlined. Conclusions. Nowadays, open PN is the gold standard technique to treat small renal masses, and all nonablative techniques must pass the test of time to be compared to PN. It is not ethical for patients to undergo radical surgery just because the urologists involved do not have adequate experience with PN. Patients should be involved in the final treatment decision and, when appropriate, referred to specialized centers with experience in open or laparoscopic partial nephrectomies.

A polymorphism in the interleukin-10 promoter affects the course of disease in patients with clear-cell renal carcinoma

In the tumor microenvironment, interleukin (IL)-10 production has a pleiotropic ability to positively and negatively influence the function of innate and adaptive immunity against cancer. This study investigated whether IL-10 genetic polymorphisms that influence gene expression levels play a role in the risk and clinical course of clear-cell renal cell carcinoma (RCC). We analyzed the allelic and haplotype frequency formed by alleles at -1082(G/A), -819(C/T), and -592(C/A) of the IL-10 gene in RCC (n = 126) and healthy individuals (n = 176). The frequency of IL-10 polymorphic variants was similar between patients and controls. However, -1082 G/A IL-10 genotype showed a significant association with three prognostic indicators: advanced disease stage (p = 0.002), higher tumor size (p = 0.001), and presence of adenopathy (p = 0.006). Our results can be explained by the contradictory antitumor or pro-tumorigenic relationship between this molecule and cancer. Genotypes associated with high or low levels of IL-10 gene expression (GG or AA-1082 IL-10) were both associated with a more favorable course of the disease. We propose the hypothesis that the -1082 GA medium expression genotype confers a tumor-promoting phenotype, likely resulting from the immunosuppressive effects of anti-tumor Th-1 responses in conjunction with the insufficient inhibition of tumor angiogenesis at this intermediate level of IL-10 expression.

Late pulmonary metastases of renal cell carcinoma immediately after post-transplantation immunosuppressive treatment: a case report.

IntroductionWe report a case of pulmonary metastatic recurrence of renal adenocarcinoma soon after radical nephrectomy that was followed by renal transplant and immunosuppressive medication. Increased risk of metastatic recurrence of renal cell carcinoma should be considered in the immediate post-transplant period when immunosuppressive medication is administered, even if nephrectomy had been performed many years earlier.Case presentationIn 1986 the patient demonstrated renal insufficiency secondary to mesangial glomerulonephritis. In 1992 he underwent left side radical nephrectomy with histopathological diagnosis of clear cell adenocarcinoma. Mesangial glomerulonephritis in the remaining right kidney progressed to end-stage renal failure. In October 2000 he received a kidney transplant from a cadaver and commenced immunosuppressive medication. Two months later, several nodules were found in his lungs, which were identified as metastases from the primary renal tumor that had been removed with the diseased kidney 8 years earlier.ConclusionRecurrence of renal cell carcinoma metastases points to tumor dormancy and reflects a misbalance between effective tumor immune surveillance and immune escape. This case demonstrates that a state of tumor dormancy can be interrupted soon after administration of immunosuppressant medication.