Predicting bortezomib-related severe neurologic adverse events by measuring proteasome activity in PBMCs

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Background: Although a proteasome inhibitor bortezomib (BOR) is one of the backbone drugs for the treatment of multiple myeloma, severe neurologic adverse event (sNE) is a major obstacle for continuing the treatment. As there is no clinically available biomarker for predicting the occurrence of sNAE, we measured the proteasome activity (PrsAtv) in peripheral blood mononuclear cells (PBMCs). Methods: Patients (Pts) were treated by either standard Q3wks or weekly (BOR 1.3mg/m2: day 1, 8, 15, 22; Q5wks) schedule depending on physician’s decision. PBMCs were collected from 21 Pts and 99 healthy volunteers. Pts’ samples were collected before treatment, 1 hour after the 1st injection of BOR, and at the end of the 1st course. PrsAtv in PBMCs was measured by using a specific substrate SUC-LLVY-AMC, which becomes fluorescent upon cleavage by proteasome. Results: Levels of PrsAtv among volunteers were highly variable with no certain correlation with age and sex. Pretreatment levels of PrsAtv among Pts were also variable, and didn't correlate with the occurrence of sNAE. After 1 hour of BOR injection, PrsAtv decreased to 33.2±20.5% (mean ± SD) of the pretreatment level, and it generally recovered (112.5±77.6%) at the end of the 1st course. However, in 12 out of 21 Pts, it didn’t recover to ≥ 100%. Among these Pts, 5 manifested with sNAE (≥G3) during the 2nd or 3rd course of the chemotherapy. In a sharp contrast, no patients whose PrsAtv recovered to ≥100% manifested with sNAE. Pts who manifested with sNAE (5 Pts) showed the lower levels of PrsAtv at the end of the 1st course than those without sNAE (16 Pts) (67.4±11.8 vs 126.6±83.8%, p=0.075). It should be also strengthened that all the Pts who manifested with sNAE were treated by the standard Q3wks schedule, although levels of PrsAtv at the end of the 1st course were not significantly different between Q3 and Q5wks groups (109.0±68.3 vs 121.1±96.4 %, p=0.38). Contrary, there was no significant difference of the bortezomib response between these two treatment groups. Conclusions: Pts whose PrsAtv does not recover to ≥100% at the end of the 1st course are at high risk of manifesting with sNAE, and these Pts should not be treated by the standard Q3wks schedule in the subsequent courses.

Oxaliplatin-induced acute-onset thrombocytopenia and hemorrhage: Case report and review of the literature

We report the case of a woman who developed acute thrombocytopenia with hemorrhagic diathesis during adjuvant treatment of colorectal adenocarcinoma with oxaliplatin, 5-fluorouracil and leucovorin. A 55-year-old woman started adjuvant chemotherapy with oxaliplatin, 5-fluorouracil and leucovorin (mFOLFOX6). Prior to starting the 12th course of chemotherapy, a complete blood cell count showed the following values: neutrophils 1800/mm(3), platelets 136,000/m(3) and hemoglobin 11.1 g/dl. A blood count revealed that the platelet levels had dropped to 35,000/mm(3), with no significant changes in hemoglobin levels following the course. The administration of corticosteroids was begun and the platelet number was recovered. Clinicians should be aware of the possibility of oxaliplatin-induced hematological emergencies during the treatment of colorectal cancer patients in order to optimize supportive treatment and avoid toxic mortality.

Possibility of molecular targeting therapy for the treatment of cancer of unknown primary origin by analysis of intracellular signaling molecules

Recently, antibody-mediated epidermal growth factor receptor (EGFR) blockade has become a major research focus, and a number of clinical studies on this new treatment have been started in the field of clinical oncology. This retrospective study investigated the role of KRAS gene mutations and clinical features for possibilities for new therapies in patients with cancer of unknown primary (CUP). We investigated the role of KRAS, PIK3CA and BRAF gene mutations and clinical features for possibilities for new therapies in patients with CUP. Nine patients with metastases from an unknown primary tumor were included in this retrospective study. The KRAS, BRAF and PI3KCA mutational analyses were carried out by means of PCR using genomic DNA for each PCR reaction. The mutation rate in CUP for codon 12 or 13 of the KRAS gene and for PIK3CA was lower than that in colorectal cancer, while the same mutation rate for BRAF was almost the same in the two; this means that the EGFR antibodies can possibly treat CUP.

The expression of podoplanin and classic cadherins in the mouse brain

Podoplanin is a transmembrane glycoprotein indirectly linked to classic cadherins through ezrin-actin networks. Recently, the overexpression of podoplanin in high-grade malignancy brain tumors has been reported. The aim of this study was to investigate the expression of podoplanin and classic cadherins in the mouse brain. Immunohistochemistry showed that podoplanin was expressed on ependymal cells and choroid plexus epithelial cells at the ventricle side of the cell surface and at the cell-cell junctions, and on retinal pigment epithelial cells and in the pia mater; P-cadherin between choroid plexus epithelial cells and endothelial cells at the basement membrane side of cell surface, and between retinal pigment epithelial cells; VE-cadherin on the PECAM-1 positive-choroid plexus endothelial cells of the fibrovascular core; and N-cadherin on the cell surface and at the cell-cell junctions of ependymal cells, and in the pia mater. The regions expressing podoplanin, P-cadherin, and VE-cadherin did not coincide. In real-time PCR analysis, the amounts of podoplanin and P- and N-cadherin mRNA were larger in the ventricular wall with choroid plexus than in the abdominal aorta and cerebrum. In the RT-PCR analysis, the intensities of amplicon for VE-cadherin mRNA were the same for the abdominal aorta, cerebrum, and ventricular wall with the choroid plexus, suggesting that mouse ependymal cells, choroid plexus epithelial cells, and glial cells under the pia mater have the ability to express podoplanin and P- and N-cadherins. Glial cells and retinal pigment epithelial cells may create barriers by podoplanin and classic cadherins as a rate-determining step for transmission of blood components.

TJ-107 for the prevention of oxaliplatin-induced peripheral neuropathy: Results of a phase II randomized placebo-controlled clinical trial

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Background: Oxaliplatin-induced peripheral neuropathy (OPN) continues to be a substantial problem for many cancer patients. In light of the promising data on TJ-107 from a previous pilot study (ASCO-GI, 2009), the present clinical trial was conducted to evaluate its efficacy for the prevention of OPN. To determine whether TJ-107 given as an adjuvant therapy effectively prevents oxaliplatin-induced peripheral neuropathy

Methods: A phase II, randomized, double-blind, placebo-controlled trial was conducted in colorectal cancer patients undergoing therapy with infusional fluorouracil, leucovorin, and oxaliplatin (FOLFOX). TJ-107 (7.5g) or matching placebo was orally administered three times daily. The primary endpoint was the incidence of grade 2 or greater OPN according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE; version 3) criteria after 8 cycles of chemotherapy. Patient-reported neurotoxicity symptoms were also assessed using the neurotoxicity subscale of the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group–Neurotoxicity (FACT/GOG-Ntx, version 4). Secondary endpoints included the incidence of all grades of OPN after each cycle and chemotherapy response rates.

Results: A total of 93 patients were enrolled from May 1, 2009 to March 31, 2010 at 37 participating GONE trial institutions in Japan. Eighty-nine evaluable patients were randomized to either the TJ-107 group (n = 44) or the placebo group (n = 45). Placebo patients showed a significantly higher rate of neurotoxicity than that of TJ-107 patients (p < 0.001), with the median difference in NTX-12 score of 3 and 3.5 at the 8th week and 26th week, respectively. There were no significant between-group differences in response to chemotherapy (55.5% in TJ-107, 39.1% in placebo). In addition, TJ-107 treatment was well tolerated overall.

Conclusions: TJ-107 shows promise in reducing the incidence of OPN. Further investigation in a larger phase III trial is necessary before any conclusions can be drawn.

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Mutations in the NOG gene are commonly found in congenital stapes ankylosis with symphalangism, but not in otosclerosis

Human noggin (NOG) is a responsible gene for multiple synostosis syndrome (SYNS1) and proximal symphalangism (SYM1), two conditions that are recently known to be within a wider range of clinical manifestations of stapes ankylosis with symphalangism. This study was performed to determine the range of phenotype caused by NOG mutations, using Japanese patients with various phenotypes including sporadic inherited SYM1, dominantly inherited SYM1, stapes ankylosis with broad thumb and toes (Teunissen and Cremer syndrome). In addition, 33 patients with typical otosclerosis (without symphalangism) were studied. Direct sequencing analysis disclosed three novel mutations of the NOG gene in three SYM1 families. None of the otosclerosis patients without symphalangism had NOG mutations, indicating that NOG mutations may be restrictively found within patients with various skeletal abnormalities. These results together with the literature review indicated that there are no clear genotype–phenotype correlations for NOG mutations. With regard to surgical outcome, most of the patients in these three families with NOG mutations showed remarkable air–bone gap recovery after stapes surgery. Molecular genetic testing is useful to differentiate syndromic stapes ankylosis from otosclerosis, and even mild skeletal anomalies can be a diagnostic indicator of NOG-associated disease.

Expression of podoplanin and classical cadherins in salivary gland epithelial cells of klotho-deficient mice

We have recently shown that salivary gland myoepithelial cells express podoplanin. Podoplanin indirectly binds the actin filament network which links classical cadherins. The study here is aimed to investigate the expression of podoplanin and cadherins on salivary gland myoepithelial cells and the changes in the aging cells using klotho-deficient (kl/kl) mice. The submandibular glands of kl/kl mouse lack granular ducts which express klotho in wild type mice, suggesting that klotho may be a gene responsible for granular duct development. Although aging resulted in growth suppression of myoepithelial cells because of the sparse distribution of the cells in kl/kl mouse salivary glands, the expression of podoplanin and E-cadherin was shown in aging myoepithelial cells. It is thought that podoplanin participates in the actin-E-cadherin networks which are maintained in aging myoepithelial cells. It was also shown that granular ducts were filled with P-cadherin, and that the P-cadherin amount was larger in the wild type mouse submandibular glands than in the sublingual and parotid glands of wild type mouse, and in the submandibular glands of kl/kl mouse. These findings suggest that the granular duct is an organ secreting soluble P-cadherin into the saliva.

Low-dose-rate, low-dose irradiation delays neurodegeneration in a model of retinitis pigmentosa

The existence of radiation hormesis is controversial. Several stimulatory effects of low-dose (LD) radiation have been reported to date; however, the effects on neural tissue or neurodegeneration remain unknown. Here, we show that LD radiation has a neuroprotective effect in mouse models of retinitis pigmentosa, a hereditary, progressive neurodegenerative disease that leads to blindness. Various LD radiation doses were administered to the eyes in a retinal degeneration mouse model, and their pathological and physiological effects were analyzed. LD gamma radiation in a low-dose-rate (LDR) condition rescues photoreceptor cell apoptosis both morphologically and functionally. The greatest effect was observed in a condition using 650 mGy irradiation and a 26 mGy/minute dose rate. Multiple rounds of irradiation strengthened this neuroprotective effect. A characteristic up-regulation (563%) of antioxidative gene peroxiredoxin-2 (Prdx2) in the LDR-LD-irradiated retina was observed compared to the sham-treated control retina. Silencing the Prdx2 using small-interfering RNA administration reduced the LDR-LD rescue effect on the photoreceptors. Our results demonstrate for the first time that LDR-LD irradiation has a biological effect in neural cells of living animals. The results support that radiation exhibits hormesis, and this effect may be applied as a novel therapeutic concept for retinitis pigmentosa and for other progressive neurodegenerative diseases regardless of the mechanism of degeneration involved.

Post-cataract surgery visual disturbance in a retinitis pigmentosa patient with asteroid hyalosis

A patient with retinitis pigmentosa showed visual disturbances following successful cataract surgery. He had a dense asteroid hyalosis in the eye before cataract surgery. After the surgery he noticed that his vision became worse. The visual disturbance was explained as being caused by the progression of retinal degeneration. Although the electroretinogram was non-recordable, the degeneration of macular area appeared relatively small. We considered that dense asteroid hyalosis was responsible for his visual disturbances, and pars plana vitrectomy (PPV) was performed to remove the asteroid hyalosis. After the PPV, rapid improvement of his visual acuity was observed. Cataract surgery may affect the status of asteroid hyalosis and cause rapid visual loss. PPV should be considered for retinitis pigmentosa patients with dense asteroid hyalosis, especially when a large decrease in visual acuity is noted shortly after cataract surgery.

The effects of cell adhesion on the growth and protein productivity of animal cells

We investigated the effect of cell adhesion on cellgrowth and productivity of recombinant protein inChinese hamster ovary (CHO) cells. Cells cultured innormal tissue culture dishes attached to the dishsurfaces and grew as a monolayer, while cells culturedin non-treated dishes proliferated in suspension assingle cells without adhering to the dish surfaces. On an agarose-coated dish surface, cell aggregatesformed without attaching to the dish. Growth rates inboth suspension cultures were slightly lower thanthose in monolayer culture. Cell cycle analysisindicated that the duration of the G(1) phase insuspension cultures was longer than that in monolayerculture, suggesting that attachment to the substratummainly affected the transition from the G(1) to theS phase. Consistent with this, CDK inhibitor p27,that inhibits the G(1)S transition, was induced inthe cells cultured in suspension.To assess the productivity of recombinant proteins,CHO cells were transfected with a plasmid containingmurine interferon gamma (mIFN-gamma) under thecontrol of the cytomegalovirus promoter. Insuspension culture, mIFN-gamma productivity wasslightly lower than that in the monolayer culture. When protein kinase C was activated by phorbol ester,mIFN-gamma production was enhanced in both themonolayer and suspension cultures. However, theproductivity in the suspension culture was lower thanthat in the adherent culture even in the presence ofhigh concentrations of phorbol ester. These resultssuggested that cell adhesion to the substratum affectsvarious features of CHO cells.

Basigin/CD147 promotes renal fibrosis after unilateral ureteral obstruction

Regardless of their primary causes, progressive renal fibrosis and tubular atrophy are the main predictors of progression to end-stage renal disease. Basigin/CD147 is a multifunctional molecule-it induces matrix metalloproteinases and hyaluronan, for example-and has been implicated in organ fibrosis. However, the relationship between basigin and organ fibrosis has been poorly studied. We investigated basigin's role in renal fibrosis using a unilateral ureteral obstruction model. Basigin-deficient mice (Bsg(-/-)) demonstrated significantly less fibrosis after surgery than Bsg(+/+) mice. Fewer macrophages had infiltrated in Bsg(-/-) kidneys. Consistent with these in vivo data, primary cultured tubular epithelial cells from Bsg(-/-) mice produced less matrix metalloproteinase and exhibited less motility on stimulation with transforming growth factor β. Furthermore, Bsg(-/-) embryonic fibro blasts produced less hyaluronan and α-smooth muscle actin after transforming growth factor β stimulation. Together, these results demonstrate for the first time that basigin is a key regulator of renal fibrosis. Basigin could be a candidate target molecule for the prevention of organ fibrosis.

Successful treatment of HTLV-1-related overlap syndrome using tacrolimus

A 56-year-old HTLV-I-positive woman, initially diagnosed as having Sjögren's syndrome, presented with muscle weakness, myalgia, face erythema and leg edema. Based on the presence of various autoantibodies, the diagnosis of overlap syndrome (dermatomyositis/Sjögren's syndrome) was made. Treatment with high-dose corticosteroid plus cyclosporine improved her symptoms. However, three months after the start of these treatments, exacerbation of myositis occurred. A muscle biopsy revealed prominent perivascular accumulation of mononuclear cells with perifascicular atrophy, which were consistent with dermatomyositis. Tacrolimus, which was substituted for cyclosporine led to marked improvement of the myositis symptoms.

Immunohistochemical examination for the distribution of podoplanin-expressing cells in developing mouse molar tooth germs

We recently reported the expression of podoplanin in the apical bud of adult mouse incisal tooth. This study was aimed to investigate the distribution of podoplanin-expressing cells in mouse tooth germs at several developing stages. At the bud stage podoplanin was expressed in oral mucous epithelia and in a tooth bud. At the cap stage podoplanin was expressed on inner and outer enamel epithelia but not in mesenchymal cells expressing the neural crest stem cell marker nestin. At the early bell stage nestin and podoplanin were expressed in cervical loop and odontoblasts. At the root formation stage both nestin and podoplanin were weakly expressed in odontoblasts generating radicular dentin. Podoplanin expression was also found in the Hertwig epithelial sheath. These results suggest that epithelial cells of developing tooth germ acquire the ability to express nestin, and that tooth germ epithelial cells maintain the ability to express podoplanin in oral mucous epithelia. The expression of podoplanin in odontoblasts was induced as tooth germ development advanced, but was suppressed with the completion of the primary dentin, suggesting that podoplanin may be involved in the cell growth of odontoblasts. Nestin may function as an intermediate filament that binds podoplanin in odontoblasts.