Marja-Liisa Karjalainen-Lindsberg

Nordic MCL2 trial update: six-year follow-up after intensive immunochemotherapy for untreated mantle cell lymphoma followed by BEAM or BEAC + autologous stem-cell support: still very long survival but late relapses do occur

Mantle cell lymphoma (MCL) is a heterogenic non‐Hodgkin lymphoma entity, with a median survival of about 5 years. In 2008 we reported the early – based on the median observation time of 4 years – results of the Nordic Lymphoma Group MCL2 study of frontline intensive induction immunochemotherapy and autologous stem cell transplantation (ASCT), with more than 60% event‐free survival at 5 years, and no subsequent relapses reported. Here we present an update after a median observation time of 6·5 years. The overall results are still excellent, with median overall survival and response duration longer than 10 years, and a median event‐free survival of 7·4 years. However, six patients have now progressed later than 5 years after end of treatment. The international MCL Prognostic Index (MIPI) and Ki‐67‐expression were the only independent prognostic factors. Subdivided by the MIPI‐Biological Index (MIPI + Ki‐67, MIPI‐B), more than 70% of patients with low‐intermediate MIPI‐B were alive at 10 years, but only 23% of the patients with high MIPI‐B. These results, although highly encouraging regarding the majority of the patients, underline the need of a risk‐adapted treatment strategy for MCL. The study was registered at www.isrctn.org as ISRCTN 87866680.

Mast cells as early responders in the regulation of acute blood–brain barrier changes after cerebral ischemia and hemorrhage

The inflammatory response triggered by stroke has been viewed as harmful, focusing on the influx and migration of blood-borne leukocytes, neutrophils, and macrophages. This review hypothesizes that the brain and meninges have their own resident cells that are capable of fast host response, which are well known to mediate immediate reactions such as anaphylaxis, known as mast cells (MCs). We discuss novel research suggesting that by acting rapidly on the cerebral vessels, this cell type has a potentially deleterious role in the very early phase of acute cerebral ischemia and hemorrhage. Mast cells should be recognized as a potent inflammatory cell that, already at the outset of ischemia, is resident within the cerebral microvasculature. By releasing their cytoplasmic granules, which contain a host of vasoactive mediators such as tumor necrosis factor-α, histamine, heparin, and proteases, MCs act on the basal membrane, thus promoting blood–brain barrier (BBB) damage, brain edema, prolonged extravasation, and hemorrhage. This makes them a candidate for a new pharmacological target in attempts to even out the inflammatory responses of the neurovascular unit, and to stabilize the BBB after acute stroke.

Cerebral mast cells regulate early ischemic brain swelling and neutrophil accumulation

We previously observed degranulated mast cells (MC) in association with perivascular brain edema formation during focal cerebral ischemia. Brain MC are typically located perivascularly and contain potent fast-acting vasoactive and proteolytic substances. We examined in a rat model of transient middle cerebral artery occlusion (MCAO) whether, in the early phase of ischemia, MC regulate microcirculation, the blood–brain barrier (BBB) permeability, and edema formation. First, animals received MC inhibitor (cromoglycate), MC-degranulating drug (compound 48/80), or saline. Thereafter, we performed transient MCAO in gene-manipulated MC-deficient rats and their wild-type (WT) littermates, calculating brain swelling, visualizing BBB leakage by intravenously administered Evans blue albumin, and determining neutrophil infiltration with light microscopy. Cerebral blood flow, monitored by laser-Doppler flowmetry in separate experiments, was similar among pharmacological treatments. Ischemic swelling resulted in increased hemispheric volume of 13.4% ± 1.0% in controls, 8.1% ± 0.4% (39% reduction) after cromoglycate, and 25.2% ± 2.0% (89% increase) after compound 48/80 (P < 0.05). Early ischemic BBB leakage was reduced by 51% after cromoglycate, and 50% enhanced by compound 48/80 (P < 0.05). The cromoglycate group showed 37% less postischemic neutrophil infiltration than did controls (P < 0.05). Furthermore, MC-deficient rats responded to focal ischemia with 58% less brain swelling (6.7% ± 1.2%) than did their WT littermates (15.8% ± 1.4%, P < 0.05). Blood-brain barrier damage was 47% lower in MC-deficient rats than in the WT (P < 0.05). Neutrophil infiltration after MCAO was decreased 47% in MC-deficient rats in comparison to WT (P < 0.05). Pharmacological MC inhibition thus appears to deserve further investigation regarding reduction of brain swelling and inflammation early after stroke.

High-resolution CT by diffraction-enhanced x-ray imaging : mapping of breast tissue samples and comparison with their histo-pathology

The aim of this study was to introduce high-resolution computed tomography (CT) of breast tumours using the diffraction-enhanced x-ray imaging (DEI) technique and to compare results with radiological and histo-pathological examinations. X-ray CT images of tumour-bearing breast tissue samples were acquired by monochromatic synchrotron radiation (SR). Due to the narrow beam and a large sample-to-detector distance scattering is rejected in the absorption contrast images (SR-CT). Large contrast enhancement is achieved by the use of the DEI-CT method, where the effects of refraction and scatter rejection are analysed by crystal optics. Clinical mammograms and CT images were recorded as reference material for a radiological examination. Three malignant and benign samples were studied in detail. Their radiographs were compared with optical images of stained histological sections. The DEI-CT images map accurately the morphology of the samples, including collagen strands and micro-calcifications of dimensions less than 0.1 mm. Histo-pathological examination and reading of the radiographs were done independently, and the conclusions were in general agreement. High-resolution DEI-CT images show strong contrast and permit visualization of details invisible in clinical radiographs. The radiation dose may be reduced by an order of magnitude without compromising image quality, which would make possible clinical in vivo DEI-CT with future compact SR sources.

Autoimmunity, hypogammaglobulinemia, lymphoproliferation, and mycobacterial disease in patients with activating mutations in STAT3

The signal transducer and activator of transcription (STAT) family of transcription factors orchestrate hematopoietic cell differentiation. Recently, mutations in STAT1, STAT5B, and STAT3 have been linked to development of immunodysregulation polyendocrinopathy enteropathy X-linked-like syndrome. Here, we immunologically characterized 3 patients with de novo activating mutations in the DNA binding or dimerization domains of STAT3 (p.K392R, p.M394T, and p.K658N, respectively). The patients displayed multiorgan autoimmunity, lymphoproliferation, and delayed-onset mycobacterial disease. Immunologically, we noted hypogammaglobulinemia with terminal B-cell maturation arrest, dendritic cell deficiency, peripheral eosinopenia, increased double-negative (CD4(-)CD8(-)) T cells, and decreased natural killer, T helper 17, and regulatory T-cell numbers. Notably, the patient harboring the K392R mutation developed T-cell large granular lymphocytic leukemia at age 14 years. Our results broaden the spectrum of phenotypes caused by activating STAT3 mutations, highlight the role of STAT3 in the development and differentiation of multiple immune cell lineages, and strengthen the link between the STAT family of transcription factors and autoimmunity.

MicroRNA profiling differentiates colorectal cancer according to KRAS status

Recent studies have shown the important role of microRNAs (miRNAs) in a variety of biological processes, and in its ability to distinguish tumors according to their prognostic and predictive properties. To identify miRNA signatures associated with colorectal carcinoma (CRC) and with KRAS status, we studied, using Agilents miRNA microarrays, miRNA expression in primary tumors from 55 metastatic CRC patients, including 15 with mutant and 40 with wild‐type KRAS. Comparing these with normal colon tissue, we identified 49 miRNAs—including 19 novel miRNAs—significantly deregulated in tumor tissue. The presence of the KRAS mutation was associated with up‐regulation of miR‐127‐3p, miR‐92a, and miR‐486‐3p and down‐regulation of miR‐378. Increased expression of miR‐127‐3p and miR‐92a in KRAS mutant tumors was significantly confirmed by quantitative reverse transcriptase polymerase chain reaction (qRT‐PCR) (P < 0.05). We identified some predicted target genes of differentially expressed miRNAs between mutated and wild‐type KRAS, such as RSG3 and TOB1, which are involved in apoptosis and proliferation. Target prediction and pathway analysis suggest a possible role for deregulated miRNAs in nicotinamide adenine dinucleotide phosphate (NADPH) regeneration and G protein‐coupled receptor signaling pathways.

Integrated gene copy number and expression microarray analysis of gastric cancer highlights potential target genes

We performed an integrated array comparative genomic hybridization (aCGH) and expression microarray analysis of 8 normal gastric tissues and 38 primary tumors, including 25 intestinal and 13 diffuse gastric adenocarcinomas to identify genes whose expression is deregulated in association with copy number alteration. Our aim was also to identify molecular genetic alterations that are specific to particular clinicopathological characteristics of gastric cancer. Distinct molecular genetic profiles were identified for intestinal and diffuse gastric cancers and for tumors obtained from 2 different locations of the stomach. Interestingly, the ERBB2 amplification and gains at 20q13.12‐q13.33 almost exclusively discriminated intestinal cancers from the diffuse type. In addition, the 17q12‐q25 gain was characteristic to cancers located in corpus and the 20q13.12‐q13.13 gain was more common in the antrum. Statistical analysis was performed using integrated copy number and expression data to identify genes showing differential expression associated with a copy number alteration. Genes with the highest statistical significance included ERBB2, MUC1, GRB7, PPP1R1B and PPARBP with concomitant changes in copy number and expression. Immunohistochemical analysis of ERBB2 and MUC1 on a tissue microarray containing 78 independent gastric tissues showed statistically significant differences (p < 0.05 and <0.001) in immunopositivity in the intestinal (31 and 70%) and diffuse subtypes (14 and 41%), respectively. In conclusion, our results demonstrate that intestinal and diffuse type gastric cancers as well as cancers located in different sites of the stomach have distinct molecular profiles which may have clinical value.

Dose-densified chemoimmunotherapy followed by systemic central nervous system prophylaxis for younger high-risk diffuse large B-cell/follicular grade 3 lymphoma patients : results of a phase II Nordic Lymphoma Group study

BACKGROUNDnMany patients with aggressive B-cell lymphomas and high clinical risk score still die of lymphoma after conventional R-CHOP chemoimmunotherapy. We hypothesized that intensified chemoimmunotherapy including systemic central nervous system (CNS) prophylaxis improves outcome and reduces the incidence of CNS-related events.nnnPATIENTS AND METHODSnInclusion criteria were age 18-65 years, primary diffuse large B-cell lymphoma or grade III follicular lymphoma without clinical signs of CNS disease and negative cerebrospinal fluid cytology, age-adjusted International Prognostic Index 2-3 and WHO performance score 0-3. Treatment consisted of six courses of R-CHOEP-14 followed by a course of high-dose cytarabine and a course of high-dose methotrexate. Primary end point was failure-free survival (FFS) at 3 years.nnnRESULTSnA total of 156 eligible patients with a median age of 54 years (range 20-64) were included. Three toxic deaths were observed. Three-year overall survival (OS) and FFS rates (median observation time 52 months for survivors) were 81% and 65%, respectively. Seven patients experienced CNS relapse, all within 6 months.nnnCONCLUSIONSnThe results are promising with favorable 3-year OS and FFS rates, a low toxic death rate and a lower than expected number of CNS events. CNS progression might be further reduced by earlier CNS prophylaxis. CinicalTrials.gov. identifier NCT01502982.

Human breast cancer in vitro: matching histo-pathology with small-angle x-ray scattering and diffraction enhanced x-ray imaging

Twenty-eight human breast tumour specimens were studied with small-angle x-ray scattering (SAXS), and 10 of those were imaged by the diffraction enhanced x-ray imaging (DEI) technique. The sample diameter was 20 mm and the thickness 1 mm. Two examples of ductal carcinoma are illustrated by histology images, DEI, and maps of the collagen d-spacing and scattered intensity in the Porod regime, which characterize the SAXS patterns from collagen-rich regions of the samples. Histo-pathology reveals the cancer-invaded regions, and the maps of the SAXS parameters show that in these regions the scattering signal differs significantly from scattering by the surrounding tissue, indicating a degradation of the collagen structure in the invaded regions. The DEI images show the borders between collagen and adipose tissue and provide a co-ordinate system for tissue mapping by SAXS. In addition, degradation of the collagen structure in an invaded region is revealed by fading contrast of the DEI refraction image. The 28 samples include fresh, defrosted tissue and formalin-fixed tissue. The d-values with their standard deviations are given. In the fresh samples there is a systematic 0.76% increase of the d-value in the invaded regions, averaged over 11 samples. Only intra-sample comparisons are made for the formalin-fixed samples, and with a long fixation time, the difference in the d-value stabilizes at about 0.7%. The correspondence between the DEI images, the SAXS maps and the histo-pathology suggests that definitive information on tumour growth and malignancy is obtained by combining these x-ray methods.

Toward High-Contrast Breast CT at Low Radiation Dose

This study was approved by the local research ethics committee, and patient informed consent was obtained. The purpose of this study was to demonstrate that high-spatial-resolution low-dose analyzer-based x-ray computed tomography (CT) can substantially improve the radiographic contrast of breast tissue in vitro when compared with that attained by using diagnostic mammography and CT. An excised human breast tumor was examined by using analyzer-based x-ray imaging with synchrotron radiation. The correspondence between analyzer-based x-ray images and diagnostic mammograms, CT images, and histopathologic findings was determined. Calcifications and fine details of soft tissue, which are at the contrast detection limit on diagnostic mammograms, are clearly visible on planar analyzer-based x-ray images. Analyzer-based x-ray CT yields high contrast from smoothly varying internal structures, such as tumorous mass lesions, corresponding to information on actual structures seen at histopathologic analysis. The mean glandular dose of 1.9 mGy in analyzer-based x-ray CT is approximately equivalent to the dose administered during single-view screening mammography. The improved visibility of mammographically indistinguishable lesions in vitro suggests that analyzer-based x-ray CT may be a valuable method in radiographic evaluation of the breast, thereby justifying further investigations.