Impact of in vivo fate of STING agonist-loaded lipid nanoparticles on antitumor immunity.

Therapeutically manipulating the stimulator of interferon genes (STING) pathway has promising potential for enhancing antitumor immunity. Agonists of this pathway (STING agonists) are being evaluated in clinical trials. Loading the STING agonists into lipid nanoparticles (LNPs) increases their safety and efficacy. We previously developed STING agonists loaded LNPs consisting of the ionizable lipid YSK12-C4 (YSK12-LNPs), which showed significant antitumor effects. However, it is largely unclear how the in vivo fate of STING agonists loaded LNPs affects the antitumor immune responses. In this study, we compared the YSK12-LNPs with LNPs composed of DLin-MC3-DMA (MC3-LNPs) showing different in vivo fates. Biodistribution and flow cytometry analyses of mouse tissues revealed that the MC3-LNPs delivered higher amounts of STING agonists to the liver than the YSK12-LNPs. Additionally, significantly more liver leukocytes internalized the MC3-LNPs than the YSK12-LNPs. In contrast, the YSK12-LNPs delivered higher amounts of STING agonists to the liver leukocytes than the MC3-LNPs, leading to the effective induction of innate immunity and inflammation in the tumors. However, the antitumor effects in the B16-F10 lung metastasis and CT26 tumor models were comparable. Interestingly, flow cytometry analyses suggested that the YSK12-LNPs were more likely to activate natural killer cells and M1 macrophages, while the MC3-LNPs were more likely to activate CD8+ T cells. Our data suggest that different antitumor immune response mechanisms may operate depending on the characteristics and distribution of the LNPs.

Pairwise Engineering of Tandemly Aligned Self-Splicing Group I Introns for Analysis and Control of Their Alternative Splicing.

Alternative splicing is an important mechanism in the process of eukaryotic nuclear mRNA precursors producing multiple protein products from a single gene. Although group I self-splicing introns usually perform regular splicing, limited examples of alternative splicing have also been reported. The exon-skipping type of splicing has been observed in genes containing two group I introns. To characterize splicing patterns (exon-skipping/exon-inclusion) of tandemly aligned group I introns, we constructed a reporter gene containing two Tetrahymena introns flanking a short exon. To control splicing patterns, we engineered the two introns in a pairwise manner to design pairs of introns that selectively perform either exon-skipping or exon-inclusion splicing. Through pairwise engineering and biochemical characterization, the structural elements important for the induction of exon-skipping splicing were elucidated.

Transformed Mycosis Fungoides with a Cytotoxic T-Cell Phenotype.

Mycosis fungoides (MF) is a cutaneous T-cell lymphoma and occasionally undergo large cell transformation (transformed MF, TMF), resulting in a poorer clinical outcome. We describe a case of TMF with an immunophenotypic shift. MF showed the CD4 + CD8- T-cell phenotype, while TMF exhibited the CD4-CD8 + T-cell phenotype. Moreover, TMF expressed cytotoxic markers of TIA1 and Granzyme B. A PCR analysis of T-cell receptor genes revealed peak sizes that were the same in both biopsies, indicating that these two lymphomas were derived from the same clone.

Clonally Related Plasmablastic Lymphoma Simultaneously Occurring with Diffuse Large B-Cell Lymphoma.

Plasmablastic lymphoma (PBL) is a rare aggressive lymphoma. Although it was first described in HIV- (human immunodeficiency virus-) infected patients, PBL has been diagnosed in patients with other immunodeficiencies as well as in immunocompetent patients. PBL immunohistochemically expresses plasmacytic markers and lacks pan B-cell markers. The cells of origin of PBL are considered to be plasmablasts. MYC gene rearrangement and MYC overexpression are frequently found in PBL, but the pathogenesis of PBL is yet to be elucidated. Here, we report a case of composite lymphoma of PBL and diffuse large B-cell lymphoma (DLBCL); that is, PBL in the urinary bladder and DLBCL in the nasal cavity occurred simultaneously. We extracted DNA from the two lymphomas for polymerase chain reaction and sequenced the amplified immunoglobulin heavy variable genes and the complementarity-determining region- (CDR-) 3. The sequence of the CDR3 region of both tumors matched. MYC rearrangement was found in the bladder tumor but not in the nasal tumor. The patient was treated with R-CHOP (rituximab, cyclophosphamide, vincristine, doxorubicin, and prednisone), and durable remission had been obtained. The results of the DNA analysis indicated that both PBL and DLBCL emerged from common postgerminal B cells. This case may help to elucidate the pathogenesis of PBL.

IgG4-related Disease with Bone Marrow Involvement.

A 61-year-old Japanese woman with anemia, submandibular gland swelling, and enlarged lymph nodes was diagnosed with IgG4-related disease (IgG4-RD) by lymph node biopsy. Bone marrow involvement of IgG4-RD was detected by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and immunohistochemically proven by bone marrow biopsy in this patient. Anemia progressed gradually, and prednisolone treatment was initiated. Anemia and submandibular gland swelling improved soon after prednisolone treatment was initiated. We report a rare case of IgG4-RD involving the bone marrow. FDG-PET/CT and bone marrow biopsy were useful for diagnosis in this case.

Immune-mediated Neuropathy with Anti-disialosyl IgM Antibodies in Diffuse Large B-cell Lymphoma: A Case Report and Literature Review.

A 36-year-old man with diffuse large B-cell lymphoma presented with polyneuropathy, and the diagnostic work-up revealed the presence of IgM antibodies against gangliosides with disialosyl residues (GD1b, GD3). He was treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone and received high-dose intravenous immunoglobulin for the treatment of neuropathy. After initiating the treatments, the patient's neurological impairment improved dramatically. He currently remains in complete remission without a flare-up of the polyneuropathy. Based upon our experience and other case reports of lymphoma with immune-mediated neuropathy caused by anti-disialosyl ganglioside IgM antibodies, we conclude that determining the anti-ganglioside antibody profile and beginning early treatment should be considered promptly for patients with malignant lymphoma who develop polyneuropathy.

Itraconazole may increase the risk of early-onset bortezomib-induced peripheral neuropathy.

Bortezomib (BOR) is an effective drug for the treatment of multiple myeloma and BOR-induced peripheral neuropathy (BIPN) is a major adverse event. BIPN tends to occur after two or three cycles of treatment (late-onset BIPN), but may occur during the first treatment cycle (early-onset BIPN). BIPN severity was retrospectively assessed and graded in 48 patients with relapsed or refractory multiple myeloma treated with BOR for the first time between June 2007 and February 2011 at Keio University Hospital. PN grade 2 or higher occurring within the first cycle of BOR was defined as early-onset severe BIPN. Early-onset severe BIPN occurred in 13 patients. Concomitant use of itraconazole [ITCZ: odds ratio (OR) 29.14 (3.02-281.56), p = 0.004] and a proton pump inhibitor [OR 9.00 (1.05-77.1), p = 0.04] were identified by univariate analysis, as risk factors for developing early-onset severe BIPN. Based on multivariate analysis, concomitant use of ITCZ was the only significant risk factor for developing early-onset severe BIPN [OR 19.00 (1.89-190.96), p = 0.01]. Concomitant use of ITCZ with BOR significantly increased the incidence of early-onset severe BIPN in our study population, suggesting that administration of ITCZ in patients receiving BOR should be avoided.

Post-transplant consolidation therapy using thalidomide alone for the patients with multiple myeloma: a feasibility study in Japanese population.

In order to test for improved survival following autologous transplantation (ASCT), we conducted a prospective clinical trial of post-ASCT thalidomide therapy in Japanese patients with multiple myeloma (MM). Twenty-five newly diagnosed patients received double or single ASCT with high-dose melphalan (200 mg/m(2)). Two months after stem cell infusion, if the patients failed to achieve a near-complete response, thalidomide was administered at 200 mg/day until disease progression or occurrence of intolerable adverse events. Seventeen patients were in partial response or minimal response after ASCT and received thalidomide alone. Their median progression-free survival (PFS) from ASCT was 17.4 months, and the median overall survival (OS) was 42.9 months. Some patients with normal karyotype experienced durable disease stabilization for over 5 years. Five patients who exhibited high-risk chromosomal changes such as t(4;14) or deletion of chromosome 13 or 17 showed very short PFS and OS compared with those who did not. Observed grade 3 or 4 toxicities included infection in three patients, hematological toxicities in three, and gastrointestinal toxicities in two, but there was no grade 3 or higher peripheral neuropathy, probably due to appropriate dose modifications. This long-term prospective study is the first to demonstrate the feasibility of post-ASCT thalidomide therapy in Japanese patients with MM.

Retrospective comparison of mobilization methods for autologous stem cell transplantation in multiple myeloma.

The combination of cyclophosphamide and granulocyte-colony stimulating factor (G-CSF) has widely been used to mobilize hematopoietic stem cells (HSCs) for autologous stem cell transplantation (ASCT) for multiple myeloma (MM). Recently, however, alternative approaches such as G-CSF alone or etoposide followed by G-CSF have been investigated. We, therefore, retrospectively analyzed the effects of these mobilization methods on collection yield and disease outcome in ASCT for MM. We reviewed 146 MM patients from whom we intended to collect stem cells. For mobilization, 67, 58, and 21 patients received cyclophosphamide and G-CSF, etoposide and G-CSF, and G-CSF alone (including nonmyelosuppressive chemotherapy followed by G-CSF), respectively. Among them, 136 achieved the target number of HSCs (at least 2 x 10(6)/kg). Lower creatinine and higher albumin levels at diagnosis were significantly associated with successful yield. A lower number of infused HSCs, use of the etoposide for mobilization and high ISS were associated with delayed hematopoietic recovery. The mobilization methods did not significantly affect either the successful collection of more than 2 x 10(6) CD34-positive cells/kg or PFS after ASCT. G-CSF alone was sufficient for stem cell mobilization for a single ASCT. The optimal approach to collect HSCs in MM remains to be elucidated.

[MTX-HOPE (methotrexate, hydrocortisone, vincristine, sobuzoxane, and etoposide) as a low-dose salvage chemotherapy for recurrent or refractory non-Hodgkin's lymphoma].

We conducted a clinical study of MTX-HOPE (day 1, methotrexate 20 mg per os (po); day 2, hydrocortisone 100 mg intravenous (iv), vincristine 1 mg iv; day 3,4 sobuzoxane 400 mg po; etoposide 25 mg po, repeating every 2 or 3 weeks) in 14 relapsed or refractory patients with non-Hodgkin's lymphoma. Ten responders were obtained 5 CR and 5 PR), and heavily treated patients were included in the responders. The median duration of over all survival which was estimated with Kaplan-Meier curve was 11.1 months (range, 2-18+ months), and the median duration of response was 6.9 months (range, 0.8+ -16.4+ months). Out of the 14 patients,eleven were treated with this regimen in an outpatient setting. Grade 4 neutropenia and thrombocytopenia were observed in 4 and 2 patients,and grade 3 GPT-elevation and stomatitis in two and one, respectively. This newly developed MTX-HOPE therapy may be a promising treatment option for such patients as are intolerable for high-dose chemotherapies with PBSC rescue or wish for outpatient therapy.

[Successful treatment with L-asparaginase-based combination chemotherapy for refractory T-cell post-transplant lymphoproliferative disorder].

A 31-year-old man underwent kidney transplantation in 1996, and had been on immunosuppressants. In 2005, he presented with discomfort on swallowing. Swelling of the left tonsil and a mediastinal mass were observed. A biopsy of the left tonsil showed a monotonous proliferation of atypical lymphocytes suggesting post-transplant lymphoproliferative disorder (PTLD). The reduction of immunosuppressants did not result in any clinical improvements, and he developed bilateral cervical lymphadenopathy. A biopsy of the cervical lymph node also showed monotonous proliferation of TdT, CD3, CD5, CD7, CD10, and CD34-positive immature cells. T-cell receptor rearrangement, but not EBER, was detected. Based on these findings, monomorphic T-cell PTLD was diagnosed. He was treated with four different chemotherapeutic regimens without any clinical improvements, and the PTLD became leukemic. Chemotherapy consisting of L-asparaginase, vincristine, and dexamethasone (LVD) was then given, which resulted in massive tumor lysis. However, after two courses of LVD, complete remission was achieved. T-cell PTLD is a rare disorder, characterized by its refractoriness to chemotherapy as opposed to B-cell PTLD. Our experience suggests that L-asparaginase-based chemotherapy may improve the prognosis of T-cell PTLD.

[A case of recurrent pleural effusion and positive cytology of advanced gastric cancer treated by TS-1 plus weekly taxane as second-line chemotherapy].

A second-line chemotherapy for advanced gastric cancer has not been established. We report a case of good response in a 39-year-old woman who had recurrent pleural effusion and positive cytology of type 4 gastric cancer and was treated with TS-1, a DPD inhibitory fluoropyrimidine, in combination with weekly taxane. After a partial response for type 4 gastric cancer from the treatment with 2 courses of TS-1 plus low-dose cisplatinum (CDDP), followed by outpatient chemotherapy with TS-1 alone or TS-1 plus weekly CDDP, left pleural effusion appeared and CA19-9 increased during the 7th course of the chemotherapy. Cytology of the effusion was class IV. The patient was treated with a course of TS-1 (120 mg/day, day 1-21) plus paclitaxel (50 mg/m2, day 1, 8) followed by 2 week washout. In the following courses, paclitaxel was replaced with docetaxel (30 mg/m2, day 1 and 8) and the course was continued in the outpatient setting. After 2 courses, the left pleural effusion disappeared and remained absent after 6 courses. Gastric biopsy showed no cancer cells and abdominal CT showed no recurrence. Serum CA19-9 doubled 1 week after taxane treatment and decreased gradually week by week during the course. This case suggests that a combination of TS-1 and taxane is effective against recurrent pleural effusion of advanced gastric cancer and useful as a second-line chemotherapy.