Abstract Cervical cancer is the third most common cancer in women worldwide, and is the most common cancer in Eastern Africa, South-Central Asia and Melanesia. Persistent HPV infection is an important feature of cervical cancer. The central role of chromosome 3q for progression from low-grade dysplastic lesions to higher grades and to invasive carcinomas has been well established. Gain of 3q can occur in morphologically normal cytology of women who developed cervical carcinomas after only a short latency. The Wig-1 gene (wt p53-induced gene 1) is located at the frequently gained chromosomal region 3q. We examined Wig-1 in eight cervical cancer cell lines (Ca Ski, ME-180, MS751, SiHa, SW 756, C-4I, C-33A, and HT-3) by FISH, Southern, Northern, qRT-PCR, and Western blotting. We did not detect any Wig-1 gene alterations in these cell lines. C33-A and HT-3 with strong Wig-1 mRNA expression were HPV negative while the HPV positive cells only exhibited low / moderate Wig-1 expression by Northern blotting. However, no association was found between Wig-1 protein expression and HPV infection. We also assessed Wig-1 expression in a series of 38 cervical tumors, including both squamous cell carcinoma (SCC) and adenocarcinoma (ADCA), by immunohistochemistry. Interestingly, patients who showed moderate nuclear Wig-1 expression levels and positive cytoplasmic Wig-1 staining in their tumors had significantly better prognosis than patients with high nuclear Wig-1 expression and no cytoplasmic staining (Log Rank P value = 0.042). Moreover, higher nuclear Wig-1 expression levels were associated with HPV negative cervical tumors (P=0.003). These results suggest that a marker like Wig-1 could have considerable impact on prediction of the prognosis in women with cervical cancer. Our previous results indicate that Wig-1 acts as a survival factor. Thus, high levels of nuclear Wig-1 may promote tumor growth and survival. The exact role of Wig-1 at the molecular level during cervical carcinoma development needs further investigation. Citation Format: Lidi Xu, Susanne Muller, Mikael Lerner, Svetlana Lagercrantz, Dan Grandér, Keng-Ling Wallin, Klas G. Wiman, Sonia Andersson, Catharina Larsson. High nuclear expression of the p53 target Wig-1 is associated with poor prognosis in cervical carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1849. doi:10.1158/1538-7445.AM2014-1849
The study was undertaken with the aim to outline deletion patterns involving the long arm of chromosome 6, a common abnormality in lymphoproliferative disorders. Using a chromosome 6 specific tile path array, 60 samples from in total 49 cases with mantle cell lymphoma (MCL), de novo diffuse large B-cell lymphoma (DLBCL), transformed DLBCL as well as preceding follicular lymphoma (FL), and childhood acute lymphoblastic leukemia (ALL), were characterized. Twenty-six of the studied cases, representing all diagnoses, showed a 6q deletion among which 85% involved a 3Mb region in 6q21. The minimal deleted interval in 6q21 encompasses the FOXO3A, PRDM1 and HACE1 candidate genes. The PRDM1 gene was found homozygously deleted in a case of DLBCL. Moreover, in two DLBCL cases, an overlapping homozygous deletion was identified in 6q23.3-24.1, encompassing the TNFAIP3 gene among others. Taken together, we refined the deletion pattern within the long arm of chromosome 6 in four different types of hematological malignances, suggesting the location of tumor suppressor genes involved in the tumor progression.
Gene profiling studies of patients with chronic lymphocytic leukemia (CLL) has revealed increased expression of Ror1, a cell surface receptor tyrosine kinase. The aim of present study was to analyze gene and protein expression of Ror1 in CLL cells and normal blood leukocytes. Gene expression analysis reverse transcription‐polymerase chain reaction of ROR1 revealed that all patients with CLL (n = 100) spontaneously expressed ROR1 mRNA whereas enriched blood B and T cells as well as granulocytes from healthy donors (n = 10) were negative. A strong nonphysiological activation signal (PMA/ionomycin) was required to induce expression in vitro in normal lymphocytes. Major genomic aberrations (mutations or truncation) of ROR1 were not observed. Protein expression was analyzed by Western blot using a panel of polyclonal anti‐Ror antibodies as well as flow cytometry. Blood lymphocytes from 18/18 CLL patients, but none of the 10 healthy donors, expressed surface Ror1. The majority of CLL cells exhibited Ror1 surface expression (71% mean; range 36–92%) with a mean fluorescence intensity (MFI) of 20 (range 10–45). The corresponding MFI of CD19 on CLL cells was 26 (range 9–48). There was no difference in the Ror1 protein expression comparing IgVH mutated and unmutated cases as well as progressive and nonprogressive CLL patients. Two different variants of the Ror1 protein, 105 and 130 kDa, were identified. The Ror1 protein expression in patients with CLL but not in normal leukocytes merits further studies of its role in the pathobiology of CLL, which may provide a basis for development of Ror1 directed targeted therapy. © 2008 Wiley‐Liss, Inc.
Diffuse large B-cell lymphomas (DLBCL) is the most common type of non-Hodgkin's lymphomas in Western countries, but also one of the most chemotherapy-responsive human malignancies. However, there i...
Mantle cell lymphoma (MCL) is characterized by over-expression of cyclin Dl as a result of the characteristic t(11;14)(q13;q32). However, this translocation alone has proven not to be sufficient for lymphomagenesis, suggesting the involvement of additional alterations. We have characterized 35 cases of MCL by array comparative genomic hybridization with an average resolution of 0.97 Mb distributed over the complete human genome. The most common alterations were losses in 1p13.2–p31.1, 6q16.2–q27, 8p21.3, 9p13.2–p24.3, 9q13–q31.3, 11q14.3–q23.3, 13q14.13–q21.31, 13q33.1–q34, and 22q11.23–q13.33 and gains involving 3q21.2–q29, 7p12.1–p22.3, 8q24.13–q24.23, and 18q21.33–q22.3. Four homozygous deletions were identified in totally three patients; two overlapping at 1p32.3, and two adjacent at 13q32.3. The homozygous deletions at 1p32.3 cover the CDKN2C locus (coding for p18), while the region at 13q32.3 does not encompass any known tumor suppressor genes. A gain in 3q was significantly associated with shorter survival (P = 0.047).
Follicular lymphoma is commonly transformed to a more aggressive diffuse large B-cell lymphoma (DLBCL). In order to molecularely characterize this histiological and clinical transformation, comparative genomic hybridization was applied on 23 follicular lymphoma and 35 transformed DLBCL tumors from a total of 30 patients. The results were also compared with our published findings in de novo DLBCL. Copy number changes were detected in 70% of follicular lymphoma and in 97% of transformed DLBCL. In follicular lymphoma, the most common alterations were +18q21 (33%), +Xq25–26 (28%), +1q31–32 (23%), and −17p (23%), whereas transformed DLBCL most frequently exhibited +Xq25–26 (36%), +12q15 (29%), +7pter-q22 (25%), +8q21 (21%), and −6q16–21(25%). Transformed DLBCL showed significantly more alterations as compared to follicular lymphoma ( P =0.0001), and the alterations −6q16–21 and +7pter-q22 were only found in transformed DLBCL but not in follicular lymphoma ( P =0.02). Alterations involving +13q22 were significantly less frequent, whereas −4q13–21 was more common in transformed as compared to de novo DLBCL ( P =0.01 and P =0.02, respectively). Clinical progression from follicular lymphoma to transformed DLBCL is on the genetic level associated with acquirement of increasing number of genomic copy number changes, with non-random involvement of specific target regions. The findings support diverse genetic background between transformed and de novo DLBCL.
Purpose: Biological dosimetry in an acute triage situation of radiation exposure is traditionally performed by scoring unstable dicentric chromosomal aberrations after conventional Giemsa staining, and more recently also by detection of chromosomal translocations after chromosome painting by fluorescence in situ hybridization ( FISH). By spectral karyotyping ( SKY) each chromosome can be painted in an individual colour, permitting the scanning for structural aberrations throughout the genome in each individual metaphase. Here we have evaluated the performance of SKY analysis in a simulated triage situation after gamma irradiation.Materials and methods: Peripheral leukocytes were irradiated by 60Co ( 0 - 5 Gy) and analysed by SKY, Giemsa staining and FISH painting of chromosomes 1, 2, and 3.Results: At 1 Gy and higher doses, dicentric aberrations (Dic+) as well as classical one- and two-way translocations were found in increasing and dose-dependent frequencies by SKY. The frequency of dicentrics detected by Giemsa was found to be significantly higher than the total aberrations detected by SKY (p<0.001), but did not differ significantly from that of FISH painting. The difference was mainly attributable to the low sensitivity of SKY to detect Dic+ following frequent lack of acentric fragments with matching chromosomal composition.Conclusions: The findings anticipate that radiation induced chromosomal aberrations may be more complex than expected from conventional and single chromosome painting analyses. While conventional Giemsa staining was found to be the method of choice for the triage situation, it is expected that extended SKY analysis will add to the knowledge of underlying mechanisms for irradiation associated chromosomal aberrations.
Several patterns of association between Hodgkin and non‐Hodgkin lymphomas are recognized, some of which support a common cellular origin or shared transformation events for both malignancies. We describe the U‐2940 cell line derived from a diffuse large B‐cell lymphoma with some features consistent with mediastinal large B‐cell lymphoma, clinically apparent 1 month after the initial course of chemotherapy for Hodgkin's disease, fulfilling the criteria for composite malignancies. U‐2940 cells display a mature B phenotype with hypermutated IgH rearrangement typical of germinal/postgerminal center origin. The cell line is negative for Epstein‐Barr virus and no evidence of t(14;18) was found. U‐2940 cells display multiple chromosomal rearrangements similar to recurrent aberrations described in both Hodgkin and non‐Hodgkin lymphomas, also partially shared by U‐2932 derived from a B‐cell lymphoma sequential to Hodgkin's disease. The original large B‐cell lymphoma and the U‐2940 cell line bear microsatellite instability, an abnormality associated with particular subtypes of non‐Hodgkin lymphomas and found in tissues involved by Hodgkin lymphoma. Therefore, U‐2940 cells bear several features known to occur in Hodgkin and in non‐Hodgkin lymphomas, leading to the assumption that this cell line may constitute a useful tool to address elective pathways of lymphomagenesis and eventually the Hodgkin and non‐Hodgkin lymphoma association. © 2005 Wiley‐Liss, Inc.
To further delineate the role of chromosomal aberrations in non-medullary thyroid tumors, we performed cytogenetic analyses of established thyroid cancer cell lines and primary tumors using spectral karyotyping (SKY), G-banding and comparative genomic hybridization (CGH). Five of the primary thyroid tumors revealed an abnormal karyotype. In a follicular thyroid carcinoma, we observed two translocations t(2;10), t(2;5) and losses of chromosomes 10p and 22. In a papillary thyroid carcinoma (PTC), a balanced translocation t(3;15) was revealed, while a case of metastatic PTC carried several clonal translocations involving ten different chromosomes. Numerical aberrations were observed in two of the five follicular adenomas analyzed, both leading to gain of chromosome 7 material. Furthermore, we cytogenetically characterized the three established thyroid cancer cell lines CGTH W-1, ARO and DRO. SKY, in combination with G-banding, revealed structural and numerical karyotypic abnormalities in all three cell lines and the breakpoint regions partly overlapped those of the primary tumors. The copy number changes detected by CGH correlated well with the karyotypic findings and demonstrated high-level amplifications in chromosomes 1, 5, 7, 8, 9, 11 and 19. The results provide evidence of chromosomal regions involved in non-medullary thyroid tumorigenesis, while further characterization of the observed translocations may lead to the identification of novel fusion oncogenes for thyroid cancer.
A preferential use of one particular immunoglobulin variable heavy chain gene, VH3–21, has recently been reported in mantle cell lymphoma, where almost all of these VH3–21+ mantle cell lymphomas showed usage of the same light chain Vλ gene (Vλ3–19) and also had a tendency towards improved prognosis. These findings suggested that VH3–21+ mantle cell lymphomas constitute a distinct subgroup, possibly with antigen stimulation involved in disease pathogenesis. In this study, we applied the comparative genomic hybridization (CGH) method on 37 mantle cell lymphoma tumors in order to investigate if the VH3–21+ tumors are different at the genomic level. Interestingly, VH3–21+ mantle cell lymphomas (n=14) showed significantly fewer genomic aberrations (mean 2.4) compared to non-VH3–21 mantle cell lymphomas (n=23) (mean 4.9). The chromosomal aberrations identified in our study were generally in accordance with previous CGH studies of mantle cell lymphoma; the most frequent aberration was complete or partial loss of chromosome 13, followed by recurrent losses within 6q, 9p, 9q and 11q and frequent gains in 3q, 7p, 8q and 15q. Deletions within 8p and 9p as well as gains in 7p and 15q were found exclusively in the non-VH3–21-utilizing tumors. In summary, VH3–21+ mantle cell lymphomas demonstrated both a lower number and a different spectrum of genomic aberrations than mantle cell lymphoma in general, thus supporting the hypothesis that VH3–21+ mantle cell lymphomas constitute a new subgroup. The findings presented in this report may explain the tendency for a better clinical outcome for patients whose tumors utilize VH3–21.
In this study seven primary kidney tumors out of 13 were cytogenetically characterized by comparative genomic hybridization (CGH) on the surgical specimens as well as by spectral karyotyping (SKY) analysis after short-term culturing. In two of the seven cases only a normal karyotype was identified. Non-clonal aberrations were observed in four of the seven cases. Overall numerical alterations were more frequent than structural changes. The two structural alterations identified constituted of a deletion of the short arm of chromosome 3 in a conventional renal cell carcinoma (RCC), and a ring chromosome derived from chromosome 8 in a papillary RCC. By CGH gains of copy number were revealed on chromosomes 3, 5, 7, 8q, and 20, while the losses encompassed 3p and 17p. In the papillary RCCs only gains were found. Comparison between SKY and CGH data suggests that the conventional RCCs are genetically more homogeneous than the other types of kidney cancer. In the two papillary RCCs, trisomies of chromosomes 7 and 17 were typical findings. In the transitional cell carcinoma different findings by CGH and SKY would suggest that these tumors constitute a heterogeneous population of tumor cells which could represent different steps of somatic evolution of tumors.
To gain further insight into the molecular events responsible for the extended life span and immortalization of human lymphoid cells, we analyzed a series of spontaneously immortalized, IL2‐dependent human T‐cell lines using molecular cytogenetic techniques. Two of the cell lines were derived from normal spleen and three from patients with Nijmegen breakage syndrome (NBS), a recessive disorder characterized by a high incidence of lymphoid malignancies. Here we show that spontaneous immortalization of the five T‐cell lines was associated with the acquisition of copy number gains involving chromosomal region 2p13–24 as common early alterations. In addition, we found an amplification of 8q21–24 after prolonged propagations in all three NBS‐derived cell lines as well as early development of near‐tetraploidy in two of these lines. Gains involving the short arm of chromosome 2 recently were found in several lymphoid malignancies. Therefore, the cell lines described here can be used for identification and characterization of genes involved in the pathogenesis of lymphoid neoplasms and would also provide a useful tool for better understanding the mechanisms responsible for cell immortalization. © 2004 Wiley‐Liss, Inc.
Hodgkin lymphoma (HL) is a malignant lymphoma composed of a minority of neoplastic cells—the Hodgkin and Reed–Sternberg (HRS) cells—and a majority of nonneoplastic inflammatory cells. The low proportion of tumor cells makes genetic studies of primary neoplasia difficult. Therefore, established HL-derived cell lines are commonly used as model systems. Here we have characterized the chromosomal composition of four such cell lines: L-540, DEV, HDLM-2, and CO. Using spectral karyotyping (SKY), reversed DAPI banding, and comparative genomic hybridization (CGH), the karyotypes were characterized and previously unidentified marker chromosomes were resolved. The karyotype for CO was incompatible with the original description but showed striking similarities with the T-ALL-derived cell line CCRF-CEM, suggesting that CO had been cross-contaminated and overgrown prior to arrival at our laboratory. Multiple numerical and structural abnormalities were identified in DEV and HDLM-2, as well as in L-540. Refined composed karyotypes are suggested for the cell lines studied, to be used as references for further studies of lymphoma.
The frequent and generalized chromosomal imbalances that are characteristic of adrenocortical carcinomas suggest that incomplete chromosome segregation often takes place in these tumors. As a step towards elucidating the mechanism behind the multiple numerical chromosomal aberrations, we have evaluated a series of 14 such tumors for centrosome abnormalities using immunohistochemical detection of the gamma-tubulin centrosome component. The proportion of cells with more than the expected number of 2 centrosomes was moderately increased in the 4 adenomas (1-7%), while a high increase was observed in the 10 carcinomas (1-19%), as compared to the normal reference tissues (0.3%) (p<0.001). Similarly, the centrosome amplification tended to be more pronounced in the carcinomas where the aberrant cells carried 3 or 4 positive signals in 9 of the 10 tumors, and 6 signals were recorded in one tumor, while in the adenomas more than 3 signals was only recorded in one of the 4 cases. The findings demonstrate that centrosome amplifications occur frequently in both adrenocortical adenomas and carcinomas, thus supporting its role in driving the tumor development as opposed to being a consequence of it. Furthermore, the more pronounced occurrence in the malignant form as well as in the larger tumors, offers one likely explanation for the increasing generalized aneuploidy observed during the tumor development, and points to new therapeutic strategies aimed at restoring normal centrosome function.
A molecular cytogenetic study was performed on the diagnostic tumor sample and three relapses from a case with blastoid mantle cell lymphoma. The clonal relatedness of the tumors was demonstrated by identical rearrangements of the immunoglobulin heavy chain gene and was supported by results from comparative genomic hybridization analyses. All samples shared the common alterations of losses of 6q, 9p, and 11q and gains of 3q, 9q, 12p, and 13q, suggesting that they were relatively early events in the tumorigenesis. Relapse 1 also showed a loss of 8p, while relapses 2 and 3 had gained the X chromosome and 7p, in addition, relapse 3 displayed gains of chromosomes 3 and 20. Taken together, the findings suggest that relapses 2 and 3 developed from the diagnostic tumor sample, while relapse 1 represents a separate lineage of tumor progression originating directly from a postulated ancestral tumor cell carrying the common chromosomal alterations identified in all tumors.
Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkin lymphoma. In contrast to many other hematological malignancies, no chromosomal abnormalities with a diagnostic or prognostic value have been identified in DLBCL. Numerical chromosomal imbalances were characterized by comparative genomic hybridization (CGH) performed on 54 DLBCL tumors from a total of 40 patients. The clonal relatedness was demonstrated in 9 of 11 pairs of matched diagnostic tumors and their relapses as determined by IGH gene rearrangement analysis and/or the CGH profiles. Furthermore, immunohistochemical expression analyses of BCL2 and BCL6/LAZ3 were performed on all cases. Copy number changes were detected in 94% of the diagnostic tumor samples and in all of the relapses. Chromosomal losses in diagnostic tumors were preferentially observed at 8p22-pter (29%), 1p34-pter (26%), 6q23-qter (20%), 17p12-pter (17%) and 22q (17%), 9p23-pter (14%), whereas gains were mainly seen in Xq25–26 (43%), 13q22 (26%), 12cen-q14 (20%), 3q24–25 (11%), 7 (11%), and 18q12–21 (11%). Loss of 22q was significantly more commonly seen in the diagnostic tumor samples with more advanced clinical stage in other words, Stage III–IV compared with Stage I–II, and band 18q21 was significantly more often gained in relapses as compared to diagnostic tumors. None of the recurrent alterations were detected as a single abnormality, suggesting that other genetic lesions below the detection level of CGH may be the initiating event in the tumorigenesis of DLBCL. However, the distribution of CGH alterations support the idea of a progression of genetic events where loss of 8p and 9p and gain of 3q, 13q, and 18q would represent relatively early events because they were distributed in tumors with only two abnormalities.
Little is known about mechanisms leading to secondary non-Hodgkin lymphomas (NHL) in patients treated for Hodgkin lymphoma (HL). Our aim was to characterise in detail a cell line derived from a diffuse large B-cell lymphoma (DLBCL) that had developed in a patient with relapsing HL. The cell line U-2932 was established from ascites in a patient suffering from DLBCL previously treated for HL with multiple chemotherapy regimens. Characterisation was based on morphology, immunophenotype, Epstein-Barr virus (EBV)-status, IgH gene rearrangement status, tumourigenicity, p53 sequencing, and immunohistochemical expression of p53, BCL-2 and BCL-6. The karyotype was investigated using G-banding, comparative genomic hybridisation (CGH) and spectral karyotype (SKY) analysis. This cell line shows typical morphological features of a DLBCL and grows as colonies in nude mice. It expresses a B-cell phenotype with a somatically hypermutated V(H)4-39 gene and is negative for EBV. The origin of U-2932 was confirmed by demonstrating an identical V(H)4 rearrangement in ascites from the patient. A point mutation of the tumour-suppressor gene p53 was detected in amino acid position 176 and immunohistochemical over-expression of the p53 protein was also demonstrated. U-2932 carries a complex karyotype including high-level amplifications of the chromosomal bands 18q21 and 3q27 and expresses aberrant BCL-2 and BCL-6 immunohistochemically. We were unable to investigate the clonal relationship between the original HL and U-2932. In conclusion, U-2932 is a unique B cell line established from a patient suffering from HL followed by NHL. Overexpression of BCL-2, BCL-6 and p53 may play a role in the tumourigenesis and drug resistance. This cell line may become a useful tool to better understand the mechanisms responsible for development of secondary NHL in patients treated for HL.