PTEN and p27 expression in mature T-cell and NK-cell neoplasms

PTEN is a tumor suppressor gene located on chromosome 10q23 and is amongst the most commonly mutated genes in human cancers. The lipid phosphatase activity of Pten enables it to dephosphorylate PIP3, thereby antagonizing growth factor stimulated PI3-kinase signaling mediated by AKT/PKB. The growth inhibition effect of PTEN has been shown to be mediated by p27 which is one of the important effector molecules downstream of the AKT pathway. Recently the importance of the Pten and AKT pathway in the regulation of the immune system and development of hematological malignancies has been shown. Loss of Pten and p27 expressions were examined immunohistochemically in 45 patients with peripheral T- and NK-cell lymphoma. Partial or complete loss of Pten was detected in 66.7% of the cases of anaplastic large cell lymphoma (ALCL) compared to only 12.5% of all other mature T-/NK-cell lymphomas combined. Loss of p27 was identified in 64.9% of cases, which showed a positive correlation with Pten loss. In this study, we showed that loss of Pten is more frequent in ALCL as compared to other mature T-/NK-cell lymphomas, which strongly correlates with the loss of p27 expression. Our findings provide further evidence for the importance of the deregulation of the PI3K-AKT pathway in ALCL.     

T-cell/NK-cell lymphomas: a review

T-cell neoplasms are a group of heterogeneous neoplasms that present a challenge in management. Accurate diagnosis and classification are necessary for proper treatment. This dilemma is exemplified by continuous upgrading of classification systems in an effort to better understand these diseases. The spectrum of management varies from observation and monitoring to prompt aggressive multimodality treatment to achieve optimal outcomes. Allogeneic transplant has been successful in a minority of cases with the possibility of cure; however this approach is still largely experimental. Molecular studies such as gene expression profiling are expected to offer exciting insight into the biology of these diseases. Novel therapeutic approaches continue to be explored, however will probably require larger clinical trials to establish their utility over the current standard.     

外周T细胞及NK细胞淋巴瘤病理研究进展

外周T细胞及自然杀伤细胞（T/NK）淋巴瘤是一组少见而又异质、以侵袭性强为特征的恶性肿瘤。由于对该组疾病的病理生物学、特别是遗传和分子生物学改变所知甚少,当前世界卫生组织（WHO）分类根据临床表现将其定义的诸多病种归类到白血病、皮肤肿瘤、结外病变以及淋巴结病变这几组疾病之中。近年来,有关T/NK细胞的亚群构成以及细胞分化方面的研究进展有助于我们更深入了解这些肿瘤的生物学特性。此外,一些新的遗传学改变以及信号路径调节失常也正被发现,这些分子层面的异常,不仅能用作诊断和预后标志物,还是研发治疗新措施的潜在靶点。      

Different T-cell receptor gene configurations in T-cell neoplasms and acute lymphoblastic leukemia.

Southern blotting and multiple restriction enzymes were used to analyze T-cell receptor (TCR) and immunoglobulin heavy chain genes in 20 postthymic T-cell neoplasms, ten prethymic and thymic T-cell tumors, and 45 cases of precursor-B acute lymphoblastic leukemia (ALL). Immunoglobulin heavy chain, never rearranged in a postthymic specimen and only once in a prethymic/thymic sample, was rearranged in all but two cases of precursor-B ALL. In contrast, biallelic rearrangement of TCR beta with deletion of the first constant region germline fragment was regularly seen in T-cell neoplasms, but only twice in the 45 precursor-B ALL cases. TCR gamma was rearranged in all but one postthymic sample, in all prethymic/thymic samples, and in approximately half of precursor-B ALL specimens as well. Preferential use of V gamma regions was evident among the various disorders: V8 and V10 in postthymic neoplasms; and V3, V5, V7, and, particularly, V9 in precursor-B ALL. In all the studied conditions, TCR delta was rarely in germline configuration. Extensive biallelic deletion of J delta 1, J delta 2, and C delta, almost always (19 of 20 specimens) present in postthymic neoplasms, was observed in only a minority (14 of 45) of precursor-B ALL samples. In precursor-B ALL, rearranged antigen receptor genes were more frequently found in common acute lymphoblastic leukemia antigen-positive and terminal deoxynucleotidyl transferase-positive specimens. Furthermore, TCR gene rearrangement in that disorder was characterized by a hierarchical pattern: TCR beta was not rearranged without TCR gamma nor TCR gamma without TCR delta. Despite uncertainty of the mechanism, the various disorders can be distinguished on the basis of characteristic antigen receptor gene patterns.     

Enteropathy-type T-cell lymphoma expressing NK-cell intraepithelial lymphocyte (NK-IEL) phenotype

Enteropathy-type T-cell lymphoma (ETL) is an intraepithelial T-lymphocyte (T-IEL) tumor. The tumor cells are usually CD3+, CD4-, CD8+, and contain cytotoxic granule associated proteins. We report on a CD3-negative CD56-positive enteropathy-associated lymphoma (ETL). This is the first case report of CD3-negative, CD56-positive, CD94-negative, and CD161-positive ETL. ETL cells originate from intraepithelial T-lymphocytes of the intestine. CD3-negative intraepithelial lymphocytes are known as natural killer (NK)-IELs. The phenotype of NK-IELs is also CD3-negative, CD56-positive, CD94-negative, and CD161-positive, while most normal NK cells express CD56 and CD94. CD3-negative lymphoma cells in this report also expressed CD56 and CD161, but not CD94. Because Southern blotting analysis showed a rearrangement of T-cell receptor (TCR) Cbeta in this case, the tumor is classified as an ETL. Based on the findings, NK-IELs may originate from T-cells, not NK-cells.     

Effects of Toll-like receptor signals in T-cell neoplasms

T-cell neoplasms have poor prognosis and few effective therapeutic options. Therefore, identification of factors in T-cell leukemia/lymphoma that are associated with cancer progression may represent novel therapeutic targets. Recent studies have highlighted a previously unappreciated role for the expression of Toll-like receptors (TLRs) on T cells and their effects on cell survival and proliferation. TLRs can bind exogenous molecules derived from pathogens as well as endogenous self-ligands released from damaged cells. Recent reports demonstrate that TLR engagement on primary mouse or human T cells enhances proliferation and/or cell survival. The mechanisms by which TLR stimulation on T cells influences these parameters and the different T-cell subsets that are affected by TLR stimulation are currently under investigation. Furthermore, neither the biological importance of stimulating TLRs on neoplastic T cells nor the prevalence of TLR expression in T-cell malignancies have yet to be characterized. Based on published reports and compelling preliminary data, we propose that the activation of the TLR-MyD88 signaling pathway in neoplastic T cells contributes to disease progression by reducing cell death and enhancing cell division. In this article, we present both theoretical arguments and experimental data in support of this hypothesis.     

CXC chemokine receptor 3 and CC chemokine receptor 4 expression in T-cell and NK-cell lymphomas with special reference to clinicopathological significance for peripheral T-cell lymphoma, unspecified.

We recently reported expression of the chemokine receptors CXC chemokine receptor 3 (CXCR3) and CC chemokine receptor 4 (CCR4) in adult T-cell leukemia/lymphoma and showed a preferential expression of CCR4 and its association with an unfavorable outcome. In the present study, we extend our adult T-cell leukemia/lymphoma study to other subtypes of T- and NK-cell lymphoma, to clarify whether a characteristic chemokine receptor expression pattern is obtained for each of the subtypes defined by the WHO classification. CXCR3 and CCR4 were rarely expressed in three well-defined subtypes, precursor T-lymphoblastic lymphoma, anaplastic lymphoma kinase-positive anaplastic large cell lymphoma, and extranodal NK/T-cell lymphoma. A CXCR3-dominant expression pattern was observed in angioimmunoblastic T-cell lymphoma, while a CCR4-dominant expression pattern was observed in mycosis fungoides in transformation and in anaplastic lymphoma kinase-negative anaplastic large cell lymphoma. CXCR3 and CCR4 were heterogeneously expressed in peripheral T-cell lymphomas, unspecified (PTCLU). We next focused on PTCLU and analyzed the clinical significance of the chemokine receptors and their association with FoxP3, a hallmark of immunoregulatory T (Treg) cells. Multivariate analysis showed that CCR4 expression was an independent and significant unfavorable prognostic factor (P < 0.001). A significant correlation was found between mRNA expression of CCR4 and FoxP3, suggesting a possible association of CCR4-positive tumors with Treg cells and thereby with an immunocompromised state. Chemokine receptors may be useful not only for further characterization of the T- and NK-cell lymphomas but also in predicting clinical outcomes for patients. We suggest that a specific therapy targeting the CCR4 molecule may be developed as an alternative treatment for patients with CCR4-positive tumors.     

Treatment algorithms for mature T-cell and natural killer-cell neoplasms

Mature T-cell and natural killer (NK)-cell lymphomas are rare neoplasms, differing geographically in frequencies. T-cell lymphomas are more common in Asia than in western countries, and NK-cell lymphomas occur almost exclusively in Asia and South America. The rarity of these lymphomas means that treatment algorithms of T-cell and NK-cell lymphomas have not been well established. Angioimmunoblastic T-cell lymphoma, anaplastic large cell lymphoma and peripheral T-cell lymphoma, not otherwise specified, are the more commonly encountered T-cell lymphomas. Treatment with anthracycline-based regimens designed for aggressive B-cell lymphomas gives unsatisfactory results. Cutaneous T-cell lymphomas may remain indolent, but outcome is poor for advanced diseases. Novel therapies, including monoclonal antibodies, nucleoside analogs, histone deacetylase inhibitors and small molecules targeting cellular signaling pathways, are being explored alone or in combination with chemotherapy. High-dose chemotherapy with hematopoietic stem cell transplantation (HSCT) is recommended for high-risk cases. NK-cell lymphomas exhibit the multidrug resistance phenotype due to P-glycoprotein expression, so that anthracycline-based regimens are ineffective. Non-multidrug resistance-dependent regimens and L-asparaginase-based protocols have been shown to be highly active. Autologous HSCT is not routinely performed. The role of allogeneic HSCT is being examined.     

NK-cell and T-cell functions in patients with breast cancer: effects of surgery and adjuvant chemo- and radiotherapy

Breast cancer is globally the most common malignancy in women. Her2-targeted monoclonal antibodies are established treatment modalities, and vaccines are in late-stage clinical testing in patients with breast cancer and known to promote tumour-killing through mechanisms like antibody-dependent cellular cytotoxicity. It is therefore increasingly important to study immunological consequences of conventional treatment strategies. In this study, functional tests and four-colour flow cytometry were used to detect natural killer (NK)-cell functions and receptors as well as T-cell signal transduction molecules and intracellular cytokines in preoperative breast cancer patients, and patients who had received adjuvant radiotherapy or adjuvant combined chemo-radiotherapy as well as in age-matched healthy controls. The absolute number of NK cells, the density of NK receptors as well as in vitro quantitation of functional NK cytotoxicity were significantly higher in preoperative patients than the post-treatments group and controls. A similar pattern was seen with regard to T-cell signalling molecules, and preoperative patients produced significantly higher amounts of cytokines in NK and T cells compared to other groups. The results indicate that functions of NK and T cells are well preserved before surgery but decrease following adjuvant therapy, which may speak in favour of early rather than late use of immunotherapeutic agents such as trastuzumab that may depend on intact immune effector functions.     

Gamma delta T-cell neoplasms: a clinicopathological study of 11 cases.

BACKGROUND: The majority of T-cell neoplasms express T-cell antigen receptor (TCR) alpha beta on their cell surface, and a few cases show the TCR gamma delta phenotype. Recently, a variety of gamma delta T-cell neoplasm was recognized; however, its clinicopathological features have not been extensively analyzed. Here we report the results of a clinicopathological study of 11 cases of gamma delta T-cell neoplasm. PATIENTS AND METHODS: During the 11-year period from 1989 to 1999, 104 patients with T-cell neoplasms were examined by flow cytometric analysis and/or immunohistochemical analysis. Tumor cells from all 104 patients expressed one or more of the T-cell antigens-CD2, CD3, CD5 and CD7. Forty-nine of the 104 cases of T-cell neoplasms were examined immunophenotypically for TCR alpha beta/gamma delta subsets. RESULTS: Expression of TCR gamma delta on tumor cells was found in five (33%) of 15 patients with precursor T-cell lymphoblastic leukemia/lymphoma, one (25%) of four with T-cell granular lymphocytic leukemia and five (26%) of 19 with peripheral T-cell lymphoma (PTCL), whereas no expression was found in 11 patients with adult T-cell leukemia-lymphoma. Primary sites of the five patients with gamma delta PTCL were as follows: lymph node, three; skin, one and liver, tonsil and skin, one. The courses of the three patients with gamma delta PTCL of nodal onset were very short (3, 5 and 9 months, respectively), and they were all resistant to combination chemotherapies. CONCLUSIONS: Although gamma delta T-cell neoplasm constitutes a heterogeneous population, it is important to examine the expression of TCR with the view to identifying possible poor prognostic subgroups, such as primary nodal gamma delta T-cell lymphoma.     

SIE-SIES-GITMO Guidelines for the management of adult peripheral T- and NK-cell lymphomas,excluding mature T-cell leukaemias

BackgroundIn order to promote widespread adoption of appropriate clinical practice, the Italian Society of Hematology (SIE), and the affiliate societies SIES (Italian Society of Experimental Hematology) and GITMO (Italian Group for Bone Marrow Transplantation) established to produce guidelines in the most relevant hematological areas. In this article, we report the recommendations for management of T/NK-cell lymphomas, excluding mature T-cell leukaemias.DesignBy using the Grades of Recommendations, Assessment, Development and Evaluation (GRADE) system, we produced evidence-based recommendations for the key clinical questions that needed to be addressed by a critical appraisal of evidence. The consensus methodology was applied to evidence-orphan issues.ResultsSix courses of cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) or cyclophosphamide, doxorubicin, vincristine, etoposide and prednisone (CHOEP) chemotherapy were recommended for first-line therapy of patients with nodal, intestinal or hepatosplenic T-cell lymphomas (evidence: low; recommendation: do, weak). Except for ALK+ anaplastic large-cell lymphoma and elderly unfit patients, consolidation with high-dose chemotherapy was recommended (evidence: low; recommendation: do, weak). 50 Gy radiotherapy was the recommended first-line therapy for localized extranodal T/NK-cell lymphoma nasal type (evidence: low; recommendation: do, strong), while l-asparaginase-containing chemotherapy regimens were recommended for patients with systemic disease (evidence: very low; recommendation: do, strong).ConclusionIn adult T/NK-cell lymphomas, GRADE methodology was applicable to a limited number of key therapeutic issues. For the remaining key issues, due to lack of appraisable evidence, recommendations was based on consensus methodology.     

Possible additional value of 18FDG-PET in managing pancreas intraductal papillary mucinous neoplasms: Preliminary results

Although some clinical and radiological features may predict malignancy presence in intraductal papillary mucinous pancreas neoplasms, preoperative diagnosis remains difficult. In this study we present 7 patients with Intraductal Papillary Mucinous Neoplasm (IPMN) studied both with 18FDG-PET and magnetic resonance cholangiopancreatography (MRCP). A focal hypermetabolism was documented in 2 patients (the standardized uptake value in the neoplastic foci was 6.7 and 9), while absence of FDG uptake in the neoplasm area was recorded in the remaining 5 cases. Mean follow-up was 27 months (range 21–34). The final judgement was benign IPMN in 5 cases and malignant IPMN in 2. PET scan always correctly predicted the presence or absence of malignancy, while MRCP failed to detect malignancy in 3/7 cases. In conclusion, this preliminary experience suggests that 18FDG-PET may prove useful for malignancy detection in IPMN, improving differential diagnosis with benign intraductal papillary growth by functional data.     

The diagnosis, management, and role of hematopoietic stem cell transplantation in aggressive peripheral T-cell neoplasms.

BACKGROUND: Peripheral T-cell neoplasms (PTCNs) comprise a group of uncommon and heterogeneous lymphoid malignancies. They are more difficult to diagnose and treat and have a worse prognosis than B-cell lymphomas. Although PTCNs initially show a significant degree of chemosensitivity, the outcome of treatment with conventional dose chemotherapy remains poor. METHODS: We reviewed the literature on the diagnosis, treatment, and collective transplant reports regarding PTCNs. RESULTS: The correct diagnosis of peripheral T-cell lymphoma requires a combination of clinical presentation, morphology, immunophenotype, and molecular study. While no specific treatment other than conventional dose chemotherapy is currently available for aggressive PTCN, histone acetylase inhibitors and monoclonal antibodies such as anti-CD7 and anti-CD52 are being studied in T-cell malignancies. The role of autologous and allogeneic transplantation is being investigated for high-risk, relapsed, and refractory PTCNs with some promising results. CONCLUSIONS: Access to hematopathology expertise in a tertiary care setting may lead to earlier and more accurate diagnoses of these diseases. PTCNs comprise a heterogeneous group of diseases with no widely accepted standard of care, and accurate determination of their histologic subtypes correlates with prognosis. Patients in first complete remission with poor risk features and patients with relapsed and refractory disease should be considered for bone marrow transplant due to the poor outcomes obtained with conventional chemotherapy.     

Natural cell-mediated cytotoxicity in rats. II. In vivo augmentation of NK-cell activity

Natural cell-mediated cytotoxicity in rats as well as in mice has been shown to vary consistently with age, with peak levels detectable at 5-10 weeks. The levels of cell-mediated cytotoxicity against tumor cells could be augmented in strains of inbred rats with either high or low levels of natural reactivity, by IP injection of a variety of agents, including C. parvum, LCMV, KRV, and poly I:C. The specificity of the augmented cytotoxicity appeared to be the same as the specificity of natural killer cells which are found in normal rat spleen cells. Similarly, the cells mediating the augmented cellular cytotoxicity were small, non-adherent, esterase-negative lymphocytes with Fc receptors, as are rat NK cells. The kinetics and organ distribution of the augmentation of NK activity by poly I:C and C. parvum were compared and the kinetics were found to differ, with a shorter time course of augmented activity seen after inoculation with poly I:C. These data indicate that interferon may play a central role in the augmentation of NK activity in vivo.     

Targeting Notch1 and proteasome as an effective strategy to suppress T-cell lymphoproliferative neoplasms

The T-cell lymphoproliferative neoplasms (T-LPN) are characterized by a poor clinical outcome. Current therapeutics are mostly non-selective and may induce harmful side effects. It has been reported that NOTCH1 activation mutations frequently associate T-LPN. Because anti-Notch1 based therapies such as γ-secretase inhibitors (GSI) are less efficient and induce considerable side effects, we hypothesized that combining low concentrations of GSI and the proteasome inhibitor bortezomib (BTZ) may provide an effective and tolerable approach to treat T-LPN. Hence, we analyzed the in vitro and in vivo effects of GSI-I and BTZ, alone or in combination, against T-LPN. GSI-I and BTZ synergistically decreased cell viability, proliferation, and colony formation, and induced apoptosis in T-LPN cell lines. Furthermore, combining GSI-I and BTZ decreased the viability of primary T-LPN cells from patients. These effects were accompanied by deregulation of Notch1, AKT, ERK, JNK, p38 MAPK, and NF-κB survival pathways. Moreover, combination treatment inhibited T-LPN tumor growth in nude mice. In all experiments, combining low concentrations of GSI-I and BTZ was superior to using a single agent. Our data support that a synergistic antitumor activity exists between GSI-I and BTZ, and provide a rationale for successful utilization of dual Notch1 and proteasome inhibition to treat T-LPN.     

Chemokine system and tissue infiltration in aggressive NK-cell leukemia

NK cell-type lymphoproliferative disease of granular lymphocytes can be subdivided into aggressive NK-cell leukemia (ANKL) and chronic NK-cell lymphocytosis (CNKL). Hepatosplenomegaly is observed in ANKL patients, and hepatic failure is a common cause of death. Significant numbers of ANKL cells were pathologically observed in sinusoidal and interlobular regions of the liver, and in the splenic red pulp. In our previous study, ANKL cells were simultaneously positive for CXCR1 and CCR5. So, in order to elucidate the mechanism in the systemic migration of ANKL cells, we investigated the expression of the corresponding chemokines in ANKL compared with CNKL. The serum level of IL-8, MIP-1alpha and MIP-1beta was significantly elevated in ANKL patients, and ANKL cells were highly positive for IL-8, RANTES, MIP-1alpha and MIP-1beta according to intracellular staining and RT-PCR. These chemokines were also positively stained in hepatocytes. The interaction between Fas and Fas ligand (FasL) is supposed to be one of the mechanisms for liver dysfunction in ANKL. The serum concentration of soluble FasL was significantly high in ANKL patients, and ANKL cells expressed FasL protein in the cytoplasm. These results suggest that the chemokine system plays an important role in the transmigration of FasL-expressing ANKL cells.     

FDG-PET. A possible prognostic factor in head and neck cancer

Previous studies have shown that high uptake of (18)F-fluoro-2-deoxy-glucose in head and neck cancer, as determined by the standardized uptake value on positron emission tomography scan, was associated with poor survival. The aim of this study was to confirm the association and to establish whether a high standardized uptake value had prognostic significance. Seventy-three consecutive patients with newly diagnosed squamous cell carcinoma of the head and neck underwent a positron emission tomography study before treatment. Age, gender, performance status tumour grade, stage, maximal tumour diameter and standardized uptake value were analyzed for their possible association with survival. The median standardized uptake value for all primary tumours was 7.16 (90% range 2.30 to 18.60). In univariate survival analysis the cumulative survival was decreased as the stage, tumour diameter and standardized uptake value increased. An standardized uptake value of 10 was taken as a cut-off for high and low uptake tumours. When these two groups were compared, an standardized uptake value >10 predicted for significantly worse outcome (P=0.003). Multivariate analysis demonstrated that an standardized uptake value >10 provided prognostic information independent of the tumour stage and diameter (P=0.002). We conclude that high FDG uptake (standardized uptake value>10) on positron emission tomography is an important marker for poor outcome in primary squamous cell carcinoma of the head and neck. Standardized uptake value may be useful in distinguishing those tumours with a more aggressive biological nature and hence identifying patients that require intensive treatment protocols including hyperfractionated radiotherapy and/or chemotherapy.