Caspase-3 activation in systemic anaplastic large-cell lymphoma.

Anaplastic large-cell lymphoma (ALCL), as currently defined, includes a subset of tumors that have abnormalities of chromosome 2p23 (alk gene) resulting in overexpression of anaplastic lymphoma kinase (ALK). We have previously shown differences in apoptotic rate and expression of apoptosis-related proteins between ALK-positive and ALK-negative ALCL. In this study, we assessed for activated caspase-3 (aC-3), an executioner of apoptotic cell death, in ALCL cell lines and tumors. We used the Karpas 299 and SU-DHL-1 cell lines, and the caspase inhibitors Boc-D-FMK and DEVD-FMK to investigate the role of caspase-3 activation in tumor cell death after treatment with doxorubicin. Cell viability and apoptosis were assessed by trypan blue and Annexin-V methods. A caspase-3 assay was used to evaluate caspase-3 enzymatic activity. Caspase-3 activity was significantly increased in Karpas-299 and SU-DHL-1 cells treated with doxorubicin, but remained as low as control levels with addition of Boc-D-FMK or DEVD-FMK. Expression of aC-3 was also assessed immunohistochemically in 57 ALCL tumors. The mean percentage of aC-3 positive tumor cells was 3.2% in ALK-positive ALCL compared with 1.2% in ALK-negative ALCL (P=0.0003, Mann-Whitney test), and inversely correlated with BCL-2 expression (P=0.01, Mann-Whitney test). aC-3 expression did not correlate with patient outcome in either the ALK-positive or ALK-negative ALCL groups. In conclusion, doxorubicin-induced cell death of ALK-positive ALCL cells involves caspase-3 activation in vitro. aC-3 levels correlate with ALK expression in ALCL tumors.     

Retinoblastoma protein is frequently absent or phosphorylated in anaplastic large-cell lymphoma

The possible role of retinoblastoma protein (Rb) in the pathogenesis of anaplastic large-cell lymphoma (ALCL) is unknown. We investigated Rb protein expression, both total (phosphorylated and underphosphorylated) and active (underphosphorylated), in four anaplastic lymphoma kinase (ALK)-positive ALCL cell lines (Karpas 299, JB-6, SU-DHL1, and SR-786) by Western blot analysis, and in 67 ALCL tumors (30 ALK-positive, 37 ALK-negative) using immunohistochemical methods. We also used fluorescence in situ hybridization and polymerase chain reaction methods to assess for loss of heterozygosity of the rb gene. The findings were correlated with apoptotic rate assessed by the terminal dUTP nick-end labeling assay. Immunoblots showed high total Rb levels in Karpas 299, SU-DHL1 and SR-786 and relatively lower levels in and JB-6. Underphosphorylated Rb was negative or expressed at low levels in all cell lines. In ALCL tumors, total Rb was detected in 44 (66%) and absent in 23 (34%). The mean apoptotic rate was 3.2% in Rb-negative tumors compared with 2.7%, 2.2%, and 1.2% in tumors with <10%, 10 to 50%, and >50% Rb-positive cells, respectively (P = 0.2, Kruskall-Wallis test). In a subset of 25 total Rb-positive tumors we assessed for underphosphorylated Rb, which was detected in 12 tumors. The detection of only total Rb in the remaining 13 tumors suggests that Rb was phosphorylated. Fluorescence in situ hybridization showed allelic loss of the rb gene in 10 (40%) of 25 tumors analyzed and was significantly associated with absence of Rb expression (P = 0.003). Similar results were obtained for loss of heterozygosity of the 13q14 locus. Five-year progression-free survival for patients with Rb-negative ALCL was 89.4% compared with 47.7% for patients with total Rb-positive ALCL (P = 0.006, log-rank test). Similar trends for progression-free survival held true for patients with ALK-positive and ALK-negative tumors analyzed separately. In conclusion, Rb is absent or phosphorylated in most ALCL cell lines and tumors and absence of Rb expression is associated with better clinical outcome in patients with ALCL.     

The nucleophosmin-anaplastic lymphoma kinase fusion protein induces c-Myc expression in pediatric anaplastic large cell lymphomas

The majority of pediatric anaplastic large cell lymphomas (ALCLs) carry the t(2;5)(p23;q35) chromosomal translocation that juxtaposes the dimerization domain of nucleophosmin with anaplastic lymphoma kinase (ALK). The nucleophosmin-ALK fusion induces constitutive, ligand-independent activation of the ALK tyrosine kinase leading to aberrant activation of cellular signaling pathways. To study the early consequences of ectopic ALK activation, a GyrB-ALK fusion was constructed that allowed regulated dimerization with the addition of coumermycin. Expression of the fusion protein caused a coumermycin-dependent increase in cellular tyrosine phosphorylation and c-Myc immunoreactivity, which was paralleled by a rise in c-myc RNA. To assess the clinical relevance of this observation, c-Myc expression was determined in pediatric ALK-positive and -negative lymphomas. Co-expression of c-Myc and ALK was seen in tumor cells in 15 of 15 (100%) ALK-positive ALCL samples, whereas no expression of either ALK or c-Myc was seen in six of six cases of ALK-negative T-cell lymphoma. C-Myc may be a downstream target of ALK signaling and its expression a defining characteristic of ALK-positive ALCLs.     

ALK-negative anaplastic large-cell lymphoma demonstrates similar poor prognosis to peripheral T-cell lymphoma, unspecified

AIMS: Anaplastic large cell lymphoma (ALCL) is classically considered a clinicopathological entity separate from other nodal mature T-cell lymphomas (TCL). Recently, the anaplastic lymphoma kinase (ALK) protein was shown to identify a subgroup of nodal ALCL with an excellent prognosis, whereas ALK-negative ALCLs are more heterogeneous. The aim of this study was to investigate the clinicopathological parameters in relation to clinical behaviour of ALK-negative ALCL compared with other nodal mature TCL, i.e. peripheral TCL, unspecified (PTCL-NOS) and angioimmunoblastic lymphoma (AILT). METHODS AND RESULTS: Clinicopathological data of ALK-positive (n = 28) and ALK-negative (n = 46) ALCL; PTCL-NOS (n = 47); and AILT (n = 12) were analysed for their prognostic significance. While ALK-positive ALCL shows favourable clinical features and a good prognosis, ALK-negative ALCL, PTCL-NOS and AILT are all associated with high age groups, advanced disease stage, and poor prognosis (<45% 5-year survival). In multivariate analysis of overall survival time, performed in the combined group of ALK-negative nodal mature T-cell lymphomas, only age and the International Prognostic Index (IPI) remained independent prognostic parameters, while lymphoma subtype (ALCL versus PTCL-NOS versus AILT) gave no additional information. CONCLUSIONS: The distinction between ALK-negative ALCL and PTCL-NOS or AILT is of limited clinical relevance as they show comparable poor prognosis. In these lymphoma subtypes, only age and the IPI are of significant prognostic value.     

间变性淋巴瘤激酶阳性和阴性系统性间变性大细胞淋巴瘤临床病理特征对比研究

目的 探讨间变性淋巴瘤激酶(ALK)阳性和阴性原发性系统性间变性大细胞淋巴瘤(ALCL)与临床病理学特征、免疫表型及分子遗传学之间的差异.方法 收集北京友谊医院病理科2003年lO月至2008年10月活检及会诊中83例ALCL.最后确诊为原发性系统性ALCL 74例,其中有8例未做ALK检测.通过分析临床资料、观察组织形态,采用免疫组织化学EliVision法检测肿瘤细胞表达CD30、ALK、上皮细胞膜抗原(EMA)、CD2、CD3、颗粒酶B/T细胞内抗原(TIA)-1的情况,采用原位杂交的方法检测EB病毒小mRNA,荧光原位杂交(FISH)方法检测染色体是否存在异常.结果 ALK~+ALCL 48例,ALK-ALCL 18例.ALK~+ALCL发病年龄明显较ALK~-ALCL年轻,中位年龄分别为18和36岁,差异有统计学意义(P＜0.05).ALK~+ALCL比ALK~-ALCL患者更多伴有发热症状(33∶4),常常是高热,并且总体存活率(80%∶71%)和中位生存时间(21个月∶12.5个月)更长,但差异均无统计学意义(P＞0.05).ALK~+ALCL更多原发于结内(81%∶56%).ALK~+ALCL和ALK~-ALCL在形态学上差异不明显,多数病例呈弥漫生长,少数表现为结节状生长;66例ALCL中均可以见到标志性细胞,8例有灶状坏死,偶见黏液基质.ALK~+ALCL主要亚型是普通型(35例),其次是淋巴组织细胞型(8例),小淋巴细胞型(3例)和肉瘤型(2例)少见;ALK~-ALCL绝大多数是普通型(17例),仅1例是淋巴组织细胞型.ALK~+ALCL总是同时表达ALK、CD30和EMA;ALK~+ALCL的EMA表达率更高(100%:72%,P＜0.05),ALK~+ALCL的T细胞标记(如CD2/CD3、CD43/CD45RO)的表达率较低,细胞毒性分子表达率较高(P＞0.05).ALCL未检测到EB病毒感染.FISH结果显示4例ALK~+ALCL中1例ALK基因正常,1例基因断裂伴多拷贝,2例仅有断裂;1例ALK~+ALCL中ALK基因正常.结论 ALK~+ALCL与ALK~-ALCL在形态学上没有显著性差异,但在临床特征和免疫表型和分子遗传学特点方面存在一定差异,这些有助于二者的鉴别诊断.     

Brain metastasis of ALK positive anaplastic large cell lymphoma after a long-term disease free survival in an old adult

Anaplastic large cell lymphoma (ALCL) is a subtype of non-Hodgkin lymphoma composed of CD30-positive cells and now recognized as three different entities: primary cutaneous ALCL, primary systemic anaplastic lymphoma kinase (ALK)-positive (ALK+) ALCL and primary ALK-negative (ALK-) ALCL. ALK+ ALCL is supposed to have a better prognosis than ALK- ALCL. It is rarely metastasized to other sites, especially to the central nervous system (CNS). Herein, we present a rare case of systemic ALK+ ALCL which metastasized to the brain after a long-term disease free survival in an adult. Neuroimaging revealed a well-enhanced mass in the left frontal lobe. And it was completely resected. The results of the pathological and immunohistochemical studies were consistent with the metastasized ALK+ ALCL. The clinical findings, pathologic characteristics and treatment are described.     

Genomic profiling of peripheral T-cell lymphoma, unspecified, and anaplastic large T-cell lymphoma delineates novel recurrent chromosomal alterations

To characterize genetic alterations in peripheral T-cell lymphoma, not otherwise specified (PTCL NOS), and anaplastic large T-cell lymphoma (ALCL), 42 PTCL NOS and 37 ALCL [17 anaplastic large cell kinase (ALK)-negative ALCL, 9 ALK-positive ALCL, 11 cutaneous ALCL] were analyzed by comparative genomic hybridization. Among 36 de novo PTCL NOS, recurrent chromosomal losses were found on chromosomes 13q (minimally overlapping region 13q21, 36% of cases), 6q and 9p (6q21 and 9p21-pter, in 31% of cases each), 10q and 12q (10q23-24 and 12q21-q22, in 28% of cases each), and 5q (5q21, 25% of cases). Recurrent gains were found on chromosome 7q22-qter (31% of cases). In 11 PTCL NOS, high-level amplifications were observed, among them 3 cases with amplification of 12p13 that was restricted to cytotoxic PTCL NOS. Whereas cutaneous ALCL and ALK-positive ALCL showed few recurrent chromosomal imbalances, ALK-negative ALCL displayed recurrent chromosomal gains of 1q (1q41-qter, 46%), and losses of 6q (6q21, 31%) and 13q (13q21-q22, 23%). Losses of chromosomes 5q, 10q, and 12q characterized a group of noncytotoxic nodal CD5+ peripheral T-cell lymphomas. The genetics of PTCL NOS and ALK-negative ALCL differ from other T-NHLs characterized genetically so far, among them enteropathy-type T-cell lymphoma, T-cell prolymphocytic leukemia, and adult T-cell lymphoma/leukemia.     

ALK-negative anaplastic large cell lymphoma primarily involving the bronchus: a case report and literature review

Anaplastic large cell lymphoma (ALCL) is a mature T cell lymphoma with characteristic morphologic, immunophenotypic and cytogenetic features. Current WHO classification includes anaplastic lymphoma kinase (ALK)-positive and ALK-negative variants. ALCL rarely presents with obstructive symptoms of the main airway. In addition to reporting a HIV-associated bronchial ALK-negative ALCL in a 44 year-old female, our literature review identified eight cases of bronchial ALCL with several interesting clinicopathological features, including: 1) a female predominance (67%); 2) two thirds of patients younger than 18 years old; 3) uniformly presented with respiratory symptoms and progressed to respiratory failure; 4) the tumor involving the main airways; 5) often with localized disease at the initial presentation. This unusual presentation of ALCL may pose as a diagnostic pitfall and delay the treatment.     

Absence of Epstein-Barr virus in anaplastic large cell lymphoma: a study of 64 cases classified according to World Health Organization criteria

The frequency of Epstein-Barr virus (EBV) in anaplastic large cell lymphoma (ALCL) has been controversial. The interpretation of previous studies is complicated by the use of nonuniform EBV detection methods and the inclusion of cases of CD30-positive diffuse large B-cell lymphoma and so-called "ALCL, Hodgkin-like," as defined in the Revised European-American Lymphoma classification scheme. In the current World Health Organization (WHO) classification system, both of these tumors are excluded from the ALCL category. Also, recently developed antibodies (eg, the antibody specific for PAX-5/B-cell-specific activator protein [BSAP]) provide new, sensitive tools for identifying neoplasms of B-cell lineage that can morphologically resemble ALCL. In this study we evaluated 64 cases of ALCL of T- or null-cell lineage, defined according to the WHO classification system, for the presence of EBV. All tumors were negative for B-cell antigens, including PAX-5/BSAP and CD20 or CD79a. The study group included 27 (42%) anaplastic lymphoma kinase (ALK)-positive (18 T-cell and 9 null-cell) and 37 (58%) ALK-negative (30 T-cell and 7 null-cell) tumors analyzed by in situ hybridization for EBV-encoded RNA (EBER) or immunohistochemistry for EBV-latent membrane protein type 1. All 64 cases were negative for EBV. We conclude, based on the current definition of ALCL in the WHO classification, there is no role for EBV in ALCL arising in Western patients. We suggest that published reports of EBV in a small proportion of ALCL cases in Western patients can be explained by the inclusion of tumors no longer considered to be in the current classification of ALCL, such as CD30-positive anaplastic tumors of B-cell origin.     

Identification of novel fusion partners of ALK,the anaplastic lymphoma kinase,in anaplastic large-cell lymphoma and inflammatory myofibroblastic tumor

ALK-positive anaplastic large-cell lymphoma (ALCL) has been recognized as a distinct type of lymphoma in the heterogeneous group of T/Null-ALCL. While most of the ALK-positive ALCL (ALKomas) are characterized by the presence of the NPM-ALK fusion protein, the product of the t(2;5)(p23;q35), 10-20% of ALKomas contain variant ALK fusions, including ATIC-ALK, TFG-ALK, CLTC-ALK (previously designated CLTCL-ALK), TMP3-ALK, and MSN-ALK. TMP3-ALK and TMP4-ALK fusions also have been detected in inflammatory myofibroblastic tumors (IMTs), making clear that aberrations of the ALK gene are not associated exclusively with the pathogenesis of ALK-positive ALCL. Here we report results of molecular studies on two lymphoma cases and one IMT case with variant rearrangements of ALK. Our study led to the detection of the CLTC-ALK fusion in an ALCL case and to the identification of two novel fusion partners of ALK: ALO17 (KIAA1618), a gene with unknown function, which was fused to ALK in an ALCL case with a t(2;17)(p23;q25), and CARS, encoding the cysteinyl-tRNA synthetase, which was fused to ALK in an IMT case with a t(2;11;2)(p23;p15;q31). These results confirm the recurrent involvement of ALK in IMT and further demonstrate the diversity of ALK fusion partners, with the ability to homodimerize as a common characteristic.     

ALK-immunoreactive neoplasms

Context

Since the first discovery of anaplastic lymphoma kinase (ALK) in anaplastic large cell lymphoma (ALCL) by Morris et al in 1994, the number of ALK-positive neoplasms, either in the form of translocation or gain-of-function mutations, have been dramatically expanded from ALCL of T- and NK-cell origin, to diffuse large B-cell lymphoma, inflammatory myofibroblastic tumor (IMT), neuroblastoma, non-small cell lung carcinoma (NSCLC), undifferentiated anaplastic thyroid carcinoma, and rare type of sarcomas.

Objective

This review covers the major aspects of ALK-immunoreactive neoplasms with emphasis on the pathogenesis of ALK-positive neoplasms. The new advances and rapid-evolving practices using ALK inhibitors for therapy are also discussed at the end of this review.

Data Sources

ALK(+) articles published in English literature are retrieved and critically reviewed.

Conclusion

ALK(+) neoplasia is a rapidly growing field and the list of ALK(+) neoplasms is being expanded continuously. Accurate and correct diagnosis of ALK(+) neoplasms is of paramount importance in guiding the appropriate treatment in the era of personalized medicine using specific ALK inhibitor.     

ALK-negative anaplastic large cell lymphoma with “Hodgkin-like” cytomorphology and nuclear expression of PAX5

Anaplastic lymphoma kinase negative systemic anaplastic large cell lymphoma (ALK-ALCL) is a CD30+ T-cell malignant lymphoma which may involve both lymph nodes and extranodal tissues, showing important clinical differences from ALK-positive ALCL (ALK + ALCL). ALK- ALCL is considered a specific entity by the 2016 World Health Organization (WHO) classification of hematolymphoid neoplasms.We describe an exceptional case of ALK- ALCL with a striking “Hodgkin-like” cytomorphology and a very uncommon nuclear expression of PAX5.