Nodular lymphocyte predominant hodgkin lymphoma and T cell/histiocyte rich large B cell lymphoma : endpoints of a spectrum of one disease?

In contrast to the commonly indolent clinical behavior of nodular lymphocyte predominant Hodgkin lymphoma (NLPHL), T cell/histiocyte rich large B cell lymphoma (THRLBCL) is frequently diagnosed in advanced clinical stages and has a poor prognosis. Besides the different clinical presentations of these lymphoma entities, there are variants of NLPHL with considerable histopathologic overlap compared to THRLBCL. Especially THRLBCL-like NLPHL, a diffuse form of NLPHL, often presents a histopathologic pattern similar to THRLBCL, suggesting a close relationship between both lymphoma entities. To corroborate this hypothesis, we performed gene expression profiling of microdissected tumor cells of NLPHL, THRLBCL-like NLPHL and THRLBCL. In unsupervised analyses, the lymphomas did not cluster according to their entity. Moreover, even in supervised analyses, very few consistently differentially expressed transcripts were found, and for these genes the extent of differential expression was only moderate. Hence, there are no clear and consistent differences in the gene expression of the tumor cells of NLPHL, THRLBCL-like NLPHL and THRLBCL. Based on the gene expression studies, we identified BAT3/BAG6, HIGD1A, and FAT10/UBD as immunohistochemical markers expressed in the tumor cells of all three lymphomas. Characterization of the tumor microenvironment for infiltrating T cells and histiocytes revealed significant differences in the cellular composition between typical NLPHL and THRLBCL cases. However, THRLBCL-like NLPHL presented a histopathologic pattern more related to THRLBCL than NLPHL. In conclusion, NLPHL and THRLBCL may represent a spectrum of the same disease. The different clinical behavior of these lymphomas may be strongly influenced by differences in the lymphoma microenvironment, possibly related to the immune status of the patient at the timepoint of diagnosis

CLDN6-specific CAR-T cells plus amplifying RNA vaccine in relapsed or refractory solid tumors:the phase 1 BNT211-01 trial

The oncofetal antigen Claudin 6 (CLDN6) is highly and specifically expressed in many solid tumors, and could be a promising treatment target. We report dose escalation results from the ongoing phase 1/2 BNT211-01 trial evaluating the safety and feasibility of chimeric antigen receptor (CAR) T cells targeting the CLDN6 with or without a CAR-T cell-amplifying RNA vaccine (CARVac) at two dose levels (DLs) in relapsed/refractory CLDN6-positive solid tumors. The primary endpoints were safety and tolerability, maximum tolerated dose and recommended phase 2 dose (RP2D). Secondary endpoints included objective response rate (ORR) and disease control rate. We observed manageable toxicity, with 10 out of 22 patients (46%) experiencing cytokine release syndrome including one grade 3 event and 1 out of 22 (5%) with grade 1 immune effector cell-associated neurotoxicity syndrome. Dose-limiting toxicities occurred in two patients at the higher DL, resolving without sequelae. CAR-T cell engraftment was robust, and the addition of CARVac was well tolerated. The unconfirmed ORR in 21 evaluable patients was 33% (7 of 21), including one complete response. The disease control rate was 67% (14 of 21), with stable disease in seven patients. Patients with germ cell tumors treated at the higher DL exhibited the highest response rate (ORR 57% (4 of 7)). The maximum tolerated dose and RP2D were not established as the trial has been amended to utilize an automated manufacturing process. A repeat of the dose escalation is ongoing and will identify a RP2D for pivotal trials. ClinicalTrials.gov Identifier: NCT04503278 .</p

Clustering genetischer Daten auf der Basis eines konsistenten Softwareframeworks zur Datenverwaltung in klinischen Studien

Diese Arbeit beschäftigt sich mit dem modellfreien Clustering von genetischen Mutationsdaten in Form von SNPs und der Qualität von Clusteringergebnissen bzw. deren Verbesserung mit Hilfe eines Softwareframeworks zur Datenverwaltung in klinischen Studien

Ectopic expression of transcription factor BATF3 induces B-cell lymphomas in a murine B-cell transplantation model

The mechanisms involved in malignant transformation of mature B and T lymphocytes are still poorly understood. In a previous study, we compared gene expression profiles of the tumor cells of Hodgkin lymphoma (HL) and anaplastic large cell lymphoma (ALCL) to their normal cellular counterparts and found the basic leucine zipper protein ATF-like 3 (BATF3) to be significantly upregulated in the tumor cells of both entities. To assess the oncogenic potential of BATF3 in lymphomagenesis and to dissect the molecular interactions of BATF3 in lymphoma cells, we retrovirally transduced murine mature T and B cells with a BATF3-encoding viral vector and transplanted each population into Rag1-deficient recipients. Intriguingly, BATF3-expressing B lymphocytes readily induced B-cell lymphomas after characteristic latencies, whereas T-cell transplanted animals remained healthy throughout the observation time. Further analyses revealed a germinal center B-cell-like phenotype of most BATF3-initiated lymphomas. In a multiple myeloma cell line, BATF3 inhibited BLIMP1 expression, potentially illuminating an oncogenic action of BATF3 in B-cell lymphomagenesis. In conclusion, BATF3 overexpression induces malignant transformation of mature B cells and might serve as a potential target in B-cell lymphoma treatment

Small and big Hodgkin-Reed-Sternberg cells of Hodgkin lymphoma cell lines L-428 and L-1236 lack consistent differences in gene expression profiles and are capable to reconstitute each other

The hallmark of classical Hodgkin lymphoma (cHL) is the presence of giant, mostly multinucleated Hodgkin-Reed-Sternberg (HRS) cells. Whereas it has recently been shown that giant HRS cells evolve from small Hodgkin cells by incomplete cytokinesis and re-fusion of tethered sister cells, it remains unsolved why this phenomenon particularly takes place in this lymphoma and what the differences between these cell types of variable sizes are. The aim of the present study was to characterize microdissected small and giant HRS cells by gene expression profiling and to assess differences of clonal growth behavior as well as susceptibility toward cytotoxic intervention between these different cell types to provide more insight into their distinct cellular potential. Applying stringent filter criteria, only two differentially expressed genes between small and giant HRS cells, SHFM1 and LDHB, were identified. With looser filter criteria, 13 genes were identified to be differentially overexpressed in small compared to giant HRS cells. These were mainly related to energy metabolism and protein synthesis, further suggesting that small Hodgkin cells resemble the proliferative compartment of cHL. SHFM1, which is known to be involved in the generation of giant cells, was downregulated in giant RS cells at the RNA level. However, reduced mRNA levels of SHFM1, LDHB and HSPA8 did not translate into decreased protein levels in giant HRS cells. In cell culture experiments it was observed that the fraction of small and big HRS cells was adjusted to the basic level several days after enrichment of these populations via cell sorting, indicating that small and big HRS cells can reconstitute the full spectrum of cells usually observed in the culture. However, assessment of clonal growth of HRS cells indicated a significantly reduced potential of big HRS cells to form single cell colonies. Taken together, our findings pinpoint to strong similarities but also some differences between small and big HRS cells

Incomplete cytokinesis and re-fusion of small mononucleated Hodgkin cells lead to giant multinucleated Reed-Sternberg cells

Multinucleated Reed-Sternberg (RS) cells are pathognomonic for classical Hodgkin lymphoma (HL), and their presence is essential for diagnosis. How these giant tumor cells develop is controversial, however. It has been postulated that RS cells arise from mononucleated Hodgkin cells via endomitosis. Conversely, continuous single-cell tracking of HL cell lines by long-term time-lapse microscopy has identified cell fusion as the main route of RS cell formation. In contrast to growth-induced formation of giant Hodgkin cells, fusion of small mononuclear cells followed by a size increase gives rise to giant RS cells. Of note, fusion of cells originating from the same ancestor, termed re-fusion, is seen nearly exclusively. In the majority of cases, re-fusion of daughter cells is preceded by incomplete cytokinesis, as demonstrated by microtubule bonds among the cells. We confirm at the level of individual tracked cells that giant Hodgkin and RS cells have little proliferative capacity, further supporting small mononuclear Hodgkin cells as the proliferative compartment of the HL tumor clone. In addition, sister cells show a shared propensity for re-fusion, providing evidence of early RS cell fate commitment. Thus, RS cell generation is related neither to cell fusion of unrelated Hodgkin cells nor to endomitosis, but rather is mediated by re-fusion of daughter cells that underwent mitosis. This surprising finding supports the existence of a unique mechanism for the generation of multinuclear RS cells that may have implications beyond HL, given that RS-like cells are frequently observed in several other lymphoproliferative diseases as well

Tumor-infiltrating HLA-matched CD4(+) T cells retargeted against Hodgkin and Reed-Sternberg cells

Hodgkin lymphoma (HL) presents with a unique histologic pattern. Pathognomonic Hodgkin and Reed-Sternberg (HRS) cells usually account for less than 1% of the tumor and are embedded in a reactive infiltrate mainly comprised of CD4(+) T cells. HRS cells induce an immunosuppressive microenvironment and thereby escape antitumor immunity. To investigate the impact of interactions between HRS cells and T cells, we performed long-term co-culture studies that were further translated into a xenograft model. Surprisingly, we revealed a strong antitumor potential of allogeneic CD4(+) T cells against HL cell lines. HRS and CD4(+) T cells interact by adhesion complexes similar to immunological synapses. Tumor-cell killing was likely based on the recognition of allogeneic major histocompatibility complex class II (MHC-II) receptor, while CD4(+) T cells from MHC-II compatible donors did not develop any antitumor potential in case of HL cell line L428. However, gene expression profiling (GEP) of co-cultured HRS cells as well as tumor infiltration of matched CD4(+) T cells indicated cellular interactions. Moreover, matched CD4(+) T cells could be activated to kill CD30(+) HRS cells when redirected with a CD30-specific chimeric antigen receptor. Our work gives novel insights into the crosstalk between HRS and CD4(+) T cells, suggesting the latter as potent effector cells in the adoptive cell therapy of HL

Effect of the anti-CD30 drug conjugate Brentuximab Vedotin to L-428 cells.

<p>Cells from the cHL line L-428 were sorted according to FSC in subpopulations of small and big cells (each 20% of total live cell population). Total live gates were sorted as control (bulk). Thereafter, subpopulations were seeded at a density of 1 x 10⁵ cells per ml in triplicates and the indicated amount of Brentuximab Vedotin was added. After 48 h cell numbers were determined by FACS. * p = 0.0117, unpaired t-test.</p

LDHB, SHFM1, and HSPA8 proteins are expressed in small and giant HRS cells.

<p>a. LDHB protein expression in small and big HRS cells in a representative primary cHL case (LDHB-immunostaining, 400x). b. SHFM1 protein expression in small and big HRS cells in a representative primary cHL case (SHFM1-immunostaining, 400x). c. HSPA8 protein expression in small and big HRS cells in a representative primary cHL case (HSPA8-immunostaining, 400x). d. Representative example of LDHB expression in small and big HRS cells in the cHL cell line L-428 (LDHB-immunofluorescence staining, 400x). e. Representative example of SHFM1 expression in small and big HRS cells in the cHL cell line L-1236 (SHFM1-immunofluorescence staining, 400x). f. Representative example of HSPA8 expression in small and big HRS cells in the cHL cell line L-428 (HSPA8-immunofluorescence staining, 400x).</p