Brentuximab vedotin in relapsed/refractory Hodgkin lymphoma. The Hellenic experience

This retrospective study aimed to describe the Hellenic experience on the use of brentuximab vedotin (BV) in relapsed/refractory (R/R) Hodgkin lymphoma (HL) given within its indication. From June 2011 to April 2015, ninety-five patients with R/R HL, who received BV in 20 centers from Greece, were analyzed. Their median age was 33 years, and 62% were males. Sixty-seven patients received BV after autologous stem cell transplantation failure, whereas 28 patients were treated with BV without a prior autologous stem cell transplantation, due to advanced age/comorbidities or chemorefractory disease. The median number of prior treatments was 4 and 44% of the patients were refractory to their most recent therapy. The median number of BV cycles was 8 (range, 2-16), and the median time to best response was the fourth cycle. Fifty-seven patients achieved an objective response: twenty-two (23%), a complete response (CR), and 35 patients (37%), a partial, for an overall response rate of 60%. Twelve patients (13%) had stable disease, and the remaining twenty-six (27%) had progressive disease as their best response. At a median follow-up of 11.5 months, median progression-free survival and overall survival were 8 and 26.5 months, respectively. Multivariate analysis showed that chemosensitivity to treatment administered before BV was associated with a significantly increased probability of achieving response to BV (P = .005). Bulky disease (P = .01) and response to BV (P <.001) were significant for progression-free survival, while refractoriness to most recent treatment (P = .04), bulky disease (P = .005), and B-symptoms (P = .001) were unfavorable factors for overall survival. Among the 22 CRs, 5 remain in CR with no further treatment after BV at a median follow-up of 13 months. In conclusion, our data indicate that BV is an effective treatment for R/R HL patients even outside clinical trials. Whether BV can cure a fraction of patients remains to be seen.

Epigenetic status of argininosuccinate synthetase and argininosuccinate lyase modulates autophagy and cell death in glioblastoma

Arginine deprivation, either by nutritional starvation or exposure to ADI-PEG20, induces adaptive transcriptional upregulation of ASS1 and ASL in glioblastoma multiforme ex vivo cultures and cell lines. This adaptive transcriptional upregulation is blocked by neoplasia-specific CpG island methylation in either gene, causing arginine auxotrophy and cell death. In cells with methylated ASS1 or ASL CpG islands, ADI-PEG20 initially induces a protective autophagic response, but abrogation of this by chloroquine accelerates and potentiates cytotoxicity. Concomitant methylation in the CpG islands of both ASS1 and ASL, observed in a subset of cases, confers hypersensitivity to ADI-PEG20. Cancer stem cells positive for CD133 and methylation in the ASL CpG island retain sensitivity to ADI-PEG20. Our results show for the first time that epigenetic changes occur in both of the two key genes of arginine biosynthesis in human cancer and confer sensitivity to therapeutic arginine deprivation. We demonstrate that methylation status of the CpG islands, rather than expression levels per se of the genes, predicts sensitivity to arginine deprivation. Our results suggest a novel therapeutic strategy for this invariably fatal central nervous system neoplasm for which we have identified robust biomarkers and which overcomes the limitations to conventional chemotherapy imposed by the blood/brain barrier.

The collagen prolyl hydroxylases are novel transcriptionally silenced genes in lymphoma

BACKGROUND

Prolyl hydroxylation is a post-translational modification that affects the structure, stability and function of proteins including collagen by catalysing hydroxylation of proline to hydroxyproline through action of collagen prolyl hydroxylases3 (C-P3H) and 4 (C-P4H). Three C-P3Hs (nomenclature was amended according to approval by the HGNC symbols and names at http://www.genenames.org/ and Entrez database at http://www.ncbi.nlm.nih.gov/gene) leucineproline-enriched proteoglycan (leprecan) 1 (Lepre1), leprecan-like 1 (Leprel1), leprecan-like 2 (Leprel2) and two paralogs Cartilage-Related Protein (CRTAP) and leprecan-like 4 (Leprel4) are found in humans. The C-P4Hs are tetrameric proteins comprising a variable α subunit, encoded by the P4HA1, P4HA2 and P4HA3 genes and a constant β subunit encoded by P4HB.

METHODS

We used RT-PCR, qPCR, pyrosequencing, methylation-specific PCR, western blotting and immunohistochemistry to investigate expression and regulation of the C-P3H and C-P4H genes in B lymphomas and normal bone marrow.

RESULTS

C-P3H and C-P4H are downregulated in lymphoma. Down-regulation is associated with methylation in the CpG islands and is detected in almost all common types of B-cell lymphoma, but the CpG islands are unmethylated or methylated at lower levels in DNA isolated from normal bone marrow and lymphoblastoid cell lines. Methylation of multiple C-P3H and C-P4H genes is present in some lymphomas, particularly Burkitt's lymphoma.

CONCLUSIONS

Methylation of C-P3H and C-P4H is common in B lymphomas and may have utility in differentiating disease subtypes.

NT5E CpG island methylation is a favourable breast cancer biomarker

BACKGROUND

Relapse risk assessment and individual treatment recommendations remain suboptimal for breast cancer patients. In the light of existing preclinical and clinical data, we studied NT5E (5'-nucleotidase, ecto) expression and NT5E CpG island methylation in breast cancer.

METHODS

We used RT-PCR, qPCR, methylation-specific PCR and pyrosequencing to analyse NT5E in breast carcinoma cell lines and primary and breast carcinomas.

RESULTS

NT5E CpG island methylation was inversely associated with NT5E expression in breast carcinoma cell lines. In clinical series, patients whose primary tumours had NT5E CpG island methylation were less likely to develop metastasis (P=0.003, OR=0.34, 95% CI: 0.17-0.69). In 3/4 paired samples, NT5E was methylated in primary tumours and demethylated in CNS metastases. Patients progressing to non-visceral as compared with visceral metastases were more likely to have NT5E CpG island methylation in primary tumours (P=0.01, OR=11.8). Patients with tumours lacking detectable methylation had shorter disease-free survival (DFS) (P=0.001, HR=2.7) and overall survival (OS) (P=0.001, HR=3). The favourable prognostic value of NT5E methylation was confirmed in oestrogen receptor negative (P=0.011, HR=3.27, 95% CI: 1.31-8.12) and in triple negative cases (P=0.004; HR=6.2, 95% CI: 1.9-20). Moreover, we observed a more favourable outcome to adjuvant chemotherapy in patients whose tumours were positive for NT5E CpG island methylation: DFS (P=0.0016, HR=5.1, 95% CI: 1.8-14.37) and OS (P=0.0005, HR=7.4, 95% CI: 2.416-23.08).

CONCLUSION

NT5E CpG island methylation is a promising breast cancer biomarker.

DUSP16 is an epigenetically regulated determinant of JNK signalling in Burkitt's lymphoma

Background:

The mitogen-activated protein kinase (MAPK) phosphatases or dual specificity phosphatases (DUSPs) are a family of proteins that catalyse the inactivation of MAPK in eukaryotic cells. Little is known of the expression, regulation or function of the DUSPs in human neoplasia.

Methods:

We used RT–PCR and quantitative PCR (qPCR) to examine the expression of DUSP16 mRNA. The methylation in the DUSP16 CpG island was analysed using bisulphite sequencing and methylation-specific PCR. The activation of MAPK was determined using western blotting with phospho-specific antibodies for extra-cellular signal-related kinase (ERK), p38 and c-Jun N-terminal kinase (JNK). The proliferation of cell lines was assessed using the CellTiter 96 Aqueous One assay.

Results:

The expression of DUSP16, which inactivates MAPK, is subject to methylation-dependent transcriptional silencing in Burkitt's Lymphoma (BL) cell lines and in primary BL. The silencing is associated with aberrant methylation in the CpG island in the 5′ regulatory sequences of the gene blocking its constitutive expression. In contrast to BL, the CpG island of DUSP16 is unmethylated in other non-Hodgkin's lymphomas (NHLs) and epithelial malignancies. In BL cell lines, neither constitutive nor inducible ERK or p38 activity varied significantly with DUSP16 status. However, activation of JNK was increased in lines with DUSP16 methylation. Furthermore, methylation in the DUSP16 CpG island blocked transcriptional induction of DUSP16, thereby abrogating a normal physiological negative feedback loop that limits JNK activity, and conferred increased cellular sensitivity to agents, such as sorbitol and anthracycline chemotherapeutic agents that activate JNK.

Conclusion:

DUSP16 is a new epigenetically regulated determinant of JNK activation in BL.

DNA methylation status of Smurf2 promoter in patients with multiple myeloma

e19537

Background: Multiple myeloma (MM) is an incurable interleukin (IL)-6 dependent plasma-cell malignancy. Transforming growth factor-β (TGF-β) is the major inducer of IL-6 secretion by bone marrow stromal cells. The signaling responses to TGF-b are mediated by the Smad proteins. The Smurf2 gene (Smad ubiqitiniation regulatory factor 2) encodes a Smad-specific E3 ubiquitin ligase and targets Smad2 and Smad3 for proteasome-dependent degradation. Methods: Bone marrow samples from individuals with MM were obtained at diagnosis and in 5 cases at disease progression as well. Genomic DNA was isolated and bisulphite modification was performed using commercially available kits. The methylation-specific polymerase chain reaction was employed to study the methylation status of the CpG island. Logistic regression analysis was used to measure the association between gene methylation and the development of advanced disease (DS≥ II), extramedullary disease, bone disease, anemia (Hb 10 mg/dl), serum albumin and beta 2 microglobulin levels. Results: We analysed the methylation of Smurf2 in 45 cases of MM (24 male, 21 female, mean age 66.4 years). No sample from the control population was found methylated. The Smurf2 gene promoter was found to be methylated in 11/45 MM patients (24%). Interesting trends were noted where patients with methylated Smurf2 promoter had an increased risk of death (HR = 1.3; p = 0.68), anemia (OR=2.1, p=0.2) and advanced stage (OR=1.3, p=0.6) and a reduced risk of extramedullary disease (OR= 0.2, p=0.2). No association was found between Smurf2 methylation status and bone lytic lesions, serum albumin levels or beta-2 microglobulin levels. Conclusions: Interesting associations between Smurf2 methylation and some relevant clinical parameters in patients with MM were suggested by the data. These findings warrant further evaluation in a larger sample of patients in order to enhance our statistical power and better define the prognostic and clinical value of Smurf2 methylation in MM.

No significant financial relationships to disclose.

Methylation reversal in high-grade B lymphoma cell lines and novel epigenetic changes conserved between immunocompetent and HIV-positive hosts

8585

Background: Methylation-dependent transcriptional silencing is an important mechanism of tumour suppressor gene inactivation in neoplasia, including lymphoma. Methods: Pharmacological “unmasking” of transcriptionally silenced genes in B lymphoma cell lines was achieved using 5' deazacytidine ± Trichostatin A and subsequent analysis of mRNA levels on micro-array. Candidate genes thus identified, were further analysed by qPCR, methylation-specific PCR (MSP) and bisulphite sequencing in B lymphoma cell lines and by MSP in clinical samples from sporadic (immunocompetent) (18 cases) and HIV-infected patients (14 cases). Samples in both patient groups were diffuse large B cell lymphoma (DLBCL) and Burkitt's lymphoma (BL). Additionally, we analysed 8 cases of marginal zone lymphoma (MZL) from the immunocompetent group. Results: We report the identification of 13 novel genes, not previously described in the literature, which are subject to methylation-dependent transcriptional silencing in high-grade lymphoma and whose expression can be reactivated by demethylating agents. The novel genes encode proteins involved in diverse functional classes and include pro-apoptotic members of the p53 pathway (Scotin), transcriptional regulators (Baz2B) and regulators of telomerase (Smrf2). The frequency of methylation in individual genes varied from approximately 10% to 75% in specific lymphoma subtypes, but was in general similar in high grade lymphomas in immunocompetent and HIV-infected hosts. Conclusions: Using pharmacological reversal of methylation, we have identified a number of genes, not previously implicated in human neoplasia, which are subject to transcriptional silencing in high-grade B lymphomas. The similar frequencies of methylation, observed in immunocompetent and HIV positive patients implies that the genes are fundamental in suppression of lymphomagenesis. Detection of methylated DNA of one or more of these genes may have utility as biomarkers of clinical outcome in each patient group.

No significant financial relationships to disclose.

Snk/Plk2 CpG methylation in patients with multiple myeloma

e19532

Background: We previously showed that polo like kinase 2 (Snk/Plk2) is subject to methylation-dependent transcriptional silencing in a very high frequency in Burkitt lymphomas. Here, we have examined CpG methylation in Snk/Plk2 in a well-characterized series of multiple myeloma (MM) patients. Methods: Bone marrow samples from individuals with MM were obtained at diagnosis and in 5 cases at disease progression as well. Genomic DNA was isolated and bisulphite modification was performed using commercially available kits. The methylation-specific polymerase chain reaction (MSP) was employed to study its methylation status. Control methylated and unmethylated genomic DNAs were included in each experiment. Ten bone marrow samples from individuals proven to have no haematological malignancy, served as negative controls. Logistic regression analyses were used to measure the association between gene methylation and the development of advanced disease (DS≥II), extramedullary disease, bone disease, anemia (Hb 10 mg/dl), serum albumin and beta 2 microglobulin levels. Results: We analyzed the methylation of Snk/Plk2 in 45 cases of MM (24 male, 21 female, mean age 66.4 years ±12.4). Classical cytogenetic analysis was available in 30/45 patients and none of them was found to have chromosome 13 abnormalities. No sample from the control population was found methylated. The Snk/Plk2 promoter was found to be methylated in 27/45 patients (60%). Median survival of patients in whom the Snk/Plk2 CpG island was methylated was 7.1 years compared to a median survival of 8.8 years for unmethylated. However Snk/Plk2 methylation was not a predictor of excess mortality (HR=0.6, p=0.5), bone lytic lesions (OR=0.56, p=0.3), anemia (OR=0.5, p=0.3) or advanced stage as defined above (OR=0.8, p=0.7). Conclusions: Snk/Plk2 DNA Methylation is a frequent event in patients with multiple myeloma. There was no association between the methylation status of the gene and relevant clinical parameters. Further evaluation in a larger sample of patients is needed in order to better define the prognostic and clinical value if any of Snk/Plk2 methylation in MM.

No significant financial relationships to disclose.

The role of immune suppression and HHV-8 in the increasing incidence of HIV-associated multicentric Castleman's disease

BACKGROUND

In HIV cohorts with access to highly active antiretroviral therapy (HAART), the incidence of Kaposi's sarcoma (KS) is falling; however, the incidence of multicentric Castleman's disease (MCD) in HIV has not previously been described.

METHODS

The incidence of HIV-associated MCD was calculated from a prospective HIV database with 56 202 patient-years of follow-up and compared with KS. Univariate and multivariate analyses were carried out to identify factors associated with MCD. Plasma human herpesvirus (HHV)-8 DNA levels were measured in HIV-seropositive individuals with newly diagnosed MCD (n = 24), KS (n = 72), HIV-associated lymphoma (n = 74) and HIV-positive controls (n = 53).

RESULTS

From 24 cases of HIV-associated MCD, the incidence measured 4.3/10,000 patient-years [95% confidence interval (CI) 2.7-6.4]. The incidence in the pre-HAART (1983-1996), early-HAART (1997-2001) and later HAART (2002-2007) eras were 2.3 (95% CI 0.02-4.2), 2.8 (95% CI 0.9-6.5) and 8.3 (95% CI 4.6-12.6), respectively, representing a statistically significant increase over time (P < 0.05). In contrast, from 1180 cases of KS, the incidence in this cohort decreased with time. Multivariate analysis demonstrated that a nadir CD4 count >200/mm(3), increased age, no previous HAART exposure and non-Caucasian ethnicity were all associated with an increased risk of MCD. Plasma HHV-8 DNA levels were higher in patients with newly diagnosed MCD than with KS, lymphomas or HIV-positive controls (Mann-Whitney U-test, P < 0.0001).

CONCLUSIONS

The incidence of HIV-associated MCD is increasing. It appears to occur more frequently in older HIV-positive individuals with well-preserved immune function.

Spontaneous splenic haematoma in a multiple myeloma patient receiving pegfilgrastim support

Growth factors are a significant advance in the supportive care of patients with cancer with a wide range of indications. Frequent side effects of G-CSF include bone pain, headache, fatigue and nausea. We report a case of subcapsular splenic haematoma following pegfilgrastim administration in a 65-year old patient with multiple myeloma. Proposed mechanisms accounting for splenic enlargement include extramedullary haemopoiesis, intrasplenic infiltration by mature and immature myeloid cells and intrasplenic stem cell homing and proliferation. The risk of spontaneous splenic rupture is difficult to quantify. Physicians should be aware of this life-threatening condition and early diagnosis can be difficult since anemia and splenomegaly are common findings in haematologic patients.

The presentation and survival of patients with non-cutaneous AIDS-associated Kaposi's sarcoma

BACKGROUND

Acquired immune deficiency syndrome related Kaposi's sarcoma (AIDS-KS) remains a significant cause of morbidity and mortality. We describe for the first time a proportion of patients with AIDS-KS who presented with no evidence of cutaneous disease.

PATIENTS AND METHODS

From our cohort of 5932 individuals infected with the human immunodeficiency virus (HIV-1) treated in the HAART era, 319 were identified with KS. Of these, 11 patients (5.4%) were diagnosed with KS without the presence of any cutaneous disease. We compared their survival, clinical, immunological and virological characteristics to other individuals with KS.

RESULTS

There were no statistically significant differences in survival, CD4 count or HIV viral load at KS presentation. We observed that tumour-associated oedema (P = 0.046) and non-oral gastrointestinal KS (P = 0.042) were significantly more common in patients with non-cutaneous KS. Only one case of non-cutaneous KS was observed prior to the era of highly active anti-retroviral therapy (HAART).

CONCLUSIONS

Non-cutaneous KS is a recognisable condition; patients should be treated with the standard of care as their prognosis is not inferior. This is likely to reflect a strong immune response, in the era of HAART.

Treatment of plasma cell leukemia with vincristine, liposomal doxorubicin and dexamethasone

Primary plasma cell (PCL) leukemia is a rare lymphoproliferative disorder characterized by a malignant proliferation of plasma cells in the bone marrow and peripheral blood. Survival with standard therapy using melphalan is very poor. Doxorubicin encapsulated with liposomes has less cardiotoxicity, is at least as efficient and has fewer side effects than conventional doxorubicin. Two female patients (69 and 54 yr old) with primary PCL are described in this study. They both received a modified form of VAD (vincristine, doxorubicin and dexamethasone), a regimen which includes liposomal doxorubicin (40 mg/m2 for 1 d), vincristine (2 mg for 1 d) and dexamethasone 40 mg per os on days 1-4, 9-12 and 17-20. A disease evaluation of the first patient after six courses of the modified \VAD regimen showed no plasma cells in the peripheral blood, a decrease in the serum M protein level and a plasma cell infiltration in the bone marrow of less than 5%. The patient died from a cardiac episode 24 months post-diagnosis, while she was in complete hematological remission. The second patient also exhibited good tolerance to liposomal doxorubicin with no side effects, achieved complete haematological remission and remains in good condition 7 months after the last VAD administration. These results suggest that this modified form of VAD regimen also seems to work in PCL and is well tolerated with no side effects.