Liposomal irinotecan with fluorouracil and leucovorin after gemcitabine-based therapy in Japanese patients with metastatic pancreatic cancer: additional safety analysis of a randomized phase 2 trial

BACKGROUND

Nanoliposomal irinotecan (nal-IRI) was recently authorized in Japan for unresectable pancreatic cancer after disease progression following chemotherapy. Physicians now consider certain aspects of nal-IRI safety profile as slightly different from conventional irinotecan. This report aims to explore additional aspects of the nal-IRI safety in Japanese phase 2 study.

METHODS

We analyzed the incidence, time to first onset, and time to resolution for adverse events that require special attention and other selected toxicities in the nal-IRI combination group (n = 46).

RESULTS

Leukopenia/neutropenia (76.1%/71.7%), diarrhea (58.7%) and hepatic dysfunction (41.3%) were the most commonly reported treatment-emergent adverse events, with a median time to onset of 21.0 days (range: 8, 97), 9.0 days (1, 61) and 22.0 days (2, 325), respectively, and a median time to resolution of 8.0 days (95% confidence intervals: 8, 9), 4.0 days (4, 8) and 40.0 days (9, -), respectively. Eight patients experienced Grade ≥ 3 diarrhea and their symptoms were well controlled by dose modification except one patient who had drug withdrawal. The median time to resolution for Grade ≥ 3 and Grade ≤ 2 diarrhea was 17.5 days (95% confidence intervals: 1, 31) and 4 days (3, 7), respectively. Anorexia occurred in 28/46 patients (60.9%) with a median time to onset of 4.0 days (range: 2, 132) and a median time to resolution of 12.0 days (95% confidence intervals: 6, 26).

CONCLUSIONS

We explored safety profile of nal-IRI combination regimen recognized as effective and tolerable treatment for Japanese unresectable pancreatic cancer patients. Although the treatment-emergent adverse events occurred were controllable, patients with prolonged toxicities should be closely managed.

Nal-IRI+5-FU/LV vs 5-FU/LV in metastatic pancreatic cancer: Additional safety report of randomized Japanese phase 2 trial

549

Background: Based on a phase II study conducted in Japanese metastatic pancreatic cancer (NCT02697058) and a global phase III study, nal-IRI obtained market authorization in March 2020 in Japan for "Unresectable pancreatic cancer after disease progression following cancer chemotherapy". After one year of practice, physicians have a sense that some of the safety profile of nal-IRI to be slightly different from conventional irinotecan. The purpose of this report is to explore additional points of the nal-IRI safety in the Japanese study. Methods: This analysis with the safety population of nal-IRI+5-FU/ l-LV group was done for the incidence, time to first onset (TTO), and time to resolution (TTR) for the events associated with 12 identified risks in the Risk Management Plan (RMP)(Table) and other selected GI toxicities. Prophylaxis used were also analyzed. Results: Myelosuppression (82.6%), diarrhoea (58.7%) and hepatic dysfunction (41.3%) were commonly reported of the 12 identified risks. The median (m) TTO of these TEAEs was 16 days (range: 6, 73), 9 days (1, 61), and 22days (2,325) respectively. As for the mTTR, it was 8.0 days (95% CI: 8.00, 9.00), 4.0 days (4.00, 8.00), and 40.0 days (9.00, -) respectively. For the myelosuppression, there were 4 patients who received G-CSF for the treatment of ≥ grade 3 myelosuppression. The 8 patients who experienced diarrhoea leading to dose reduction had no recurrence of ≥grade3 diarrhoea after intervention. For other GI toxicities, anorexia occurred in 28/46 patients (60.9%) with mTTO 4.0 days (range: 2, 132) and mTTR 12.0 days (95% CI: 6.00, 26.00). Summary of TTO for the events associated with identified risks in the RMP. * Intestinal obstruction, enteritis, disseminated intravascular coagulation, interstitial lung disease, ventricular extrasystoles are also included in the RMP but not observed. Discussion: This is the first report of nal-IRI safety profile details such as timing in Japanese patients. It is interesting to note that some TEAEs appear different in practice regarding TTR in comparison with conventional irinotecan. This difference can be due to the unique PK profile of nal-IRI as a result of utilizing liposomal technology but needs to be further elucidated. Conclusions: Although the TEAEs occurred with nal-IRI+5-FU/ l-LV were controllable with proper management in Japanese patients, some with prolonged toxicities should be carefully managed. Clinical trial information: NCT02697058. [Table: see text]

Determination of reactivation rate and risk factors for Hepatitis B virus reactivation in low-positive cases: A retrospective cohort study

INTRODUCTION

In quantitative assays for hepatitis B virus (HBV) DNA, although the amplification reaction signal is detected for low-positive cases, quantification remains challenging. HBV reactivation has been reported in many studies, but only a few have focused on HBV low-positive cases. This study aimed to determine the reactivation rate and risk factors for HBV reactivation in low-positive cases.

METHODS

In this retrospective cohort study, we analyzed 7498 patients who had their HBV DNA measured at Sapporo Medical University Hospital between April 2008 and November 2020. Patient selection criteria were defined as follows: hepatitis B surface antigen was negative; HBV DNA was detectable but not quantifiable at least once. HBV DNA was monitored according to the guidelines for HBV reactivation.

RESULTS

In total, 49,086 HBV DNA quantitative tests were performed. HBV DNA levels of 2578 tests were detectable but not quantifiable. Eighty patients met the criteria in this study. The median observation period was 497 days, and the 2-year reactivation rate was 15%. Ten patients had low HBV DNA positivity at baseline. Malignant lymphoma was observed in 15 patients; chemotherapy was used to treat other solid tumors in 35 patients, and immunosuppressive therapy was used in 30 patients. Multivariate analysis revealed that HBV DNA detected below the quantification level at baseline was an independent risk factor for HBV reactivation (adjusted hazard ratio 5.82; P = 0.010).

CONCLUSIONS

Patients with low HBV DNA positivity, especially at baseline, are at high risk for HBV reactivation and therefore require closer monitoring.

P1802 Prevalence and prognostic significance of pulmonary artery aneurysms in patients with pulmonary artery hypertension

Background

Pulmonary artery aneurysm (PAA) occurs in some patients with pulmonary arterial hypertension (PAH) and can be accompanied by various complications.

Objective

The aim of the this study is to evaluate the characteristics of cardiac dysfunction and the prognostic impact of PAA by analysing the outcome of patients with PAH complicated by PAA.

Methods

We performed echocardiography and right-heart catheterization in 130 PAH patients. We measured the maximum dimensions of the main pulmonary artery (MPA) trunk. We evaluated the right ventricular (RV) function and the five-year prognosis of patients with PAA.

Results

The maximum MPA trunk diameter of >40 mm by echocardiography was defined as PAA. PAA appeared in 32 of the 130 PAH patients (24.6%: Group PAA), other 98 patients were defined as Group non-PAA. Systolic pulmonary artery pressure (76 ±18 vs. 61 ± 21 mmHg, P = 0.0008) and mean right atrial pressure (10.0 ± 8.1 vs. 5.4 ± 3.8 mmHg, P < 0.0001) were significantly higher in Group PAA than in Group non-PAA. RV end-diastolic area index was significantly larger (37.3 ± 8.8 vs. 32.3 ± 7.8 mmHg, P = 0.0048), and RV fractional area change (32 ± 8 vs. 36 ± 9 %, P = 0.0176) and RV longitudinal strain amplitude (-16 ±5 vs. -20 ± 6, P = 0.0017) were significantly lower in Group PAA than those in Group non-PAA. During the five-year follow-up period, 20 patients (15%) died. The five-year mortality rate was significantly higher in Group PAA compared to Group non-PAA (30% vs. 10%, P = 0.007).

Conclusion

In PAH patients with PAA, RV dysfunction was more severe and the prognosis was poor. Assessment of PAA can be a useful index for the extraction of high-risk PAH patients.

Tumors induce coordinate growth of artery, vein, and lymphatic vessel triads

BACKGROUND

Tumors drive blood vessel growth to obtain oxygen and nutrients to support tumor expansion, and they also can induce lymphatic vessel growth to facilitate fluid drainage and metastasis. These processes have generally been studied separately, so that it is not known how peritumoral blood and lymphatic vessels grow relative to each other.

METHODS

The murine B16-F10 melanoma and chemically-induced squamous cell carcinoma models were employed to analyze large red-colored vessels growing between flank tumors and draining lymph nodes. Immunostaining and microscopy in combination with dye injection studies were used to characterize these vessels.

RESULTS

Each peritumoral red-colored vessel was found to consist of a triad of collecting lymphatic vessel, vein, and artery, that were all enlarged. Peritumoral veins and arteries were both functional, as detected by intravenous dye injection. The enlarged lymphatic vessels were functional in most mice by subcutaneous dye injection assay, however tumor growth sometimes blocked lymph drainage to regional lymph nodes. Large red-colored vessels also grew between benign papillomas or invasive squamous cell carcinomas and regional lymph nodes in chemical carcinogen-treated mice. Immunostaining of the red-colored vessels again identified the clustered growth of enlarged collecting lymphatics, veins, and arteries in the vicinity of these spontaneously arising tumors.

CONCLUSIONS

Implanted and spontaneously arising tumors induce coordinate growth of blood and lymphatic vessel triads. Many of these vessel triads are enlarged over several cm distance between the tumor and regional lymph nodes. Lymphatic drainage was sometimes blocked in mice before lymph node metastasis was detected, suggesting that an unknown mechanism alters lymph drainage patterns before tumors reach draining lymph nodes.

Comparative validity of the WHO-5 Well-Being Index and two-question instrument for screening depressive symptoms in patients with type 2 diabetes

A simple tool consisting of two questions for screening depressive symptoms has been shown to be useful in primary care settings, but its validity in patients with diabetes has yet to be evaluated. We compared the test performance of this two-question instrument with that of WHO (The World Health Organization)-5. We consecutively enrolled 153 patients with type 2 diabetes who visited a diabetes clinic in Japan. Using the Center for Epidemiologic Studies Depression Scale as a reference standard of depressive symptoms, we calculated the sensitivity and specificity of the two-question instrument and WHO-5, and compared the area under the ROC curves of these tests. The two-question instrument had a sensitivity of 53.6% (95% CI, 39.7-67.0%) and specificity of 67.7% (95% CI, 58.1-74.9%). With the conventional cutoff point equal to or less than 13 points, the WHO-5 had a sensitivity of 57.1% (95% CI, 43.2-70.3%) and specificity of 82.5% (95% CI, 81.9-94.9%). The area under the ROC curve for the WHO-5 and two-item questionnaire, an indicator of discriminatory power, was 0.81 and 0.73, respectively, showing a statistically significant difference (P = 0.0453). The two-question instrument had statistically lower discriminatory power than the WHO-5 in screening depressive symptoms in patients with diabetes. We do not recommend the use of the two-question instrument for screening depressive symptoms in patients with diabetes.

Elevated expression of angiomodulin (AGM/IGFBP-rP1) in tumor stroma and its roles in fibroblast activation

Angiomodulin (AGM/IGFBP-rP1), a glycoprotein of about 30 kDa, is overexpressed in tumor vasculature as well as some human cancer cell lines, but it has been suggested to be a tumor suppressor. To elucidate roles of angiomodulin (AGM) in tumor progression, we here examined distribution of AGM in three types of human cancer tissues by immunohistochemistry. The results showed that AGM was overexpressed in the stroma as well as the vasculature surrounding tumor cells in the human cancer tissues. AGM and α-smooth muscle actin (α-SMA) as an activated fibroblast marker were often colocalized in cancer-associated fibroblasts (CAFs). In vitro analysis indicated that transforming growth factor (TGF)-β1 might be an important inducer of AGM in normal human fibroblasts. AGM strongly stimulated the expression of fibronectin and weakly that of α-SMA in normal fibroblasts. AGM significantly stimulated the proliferation and migration of fibroblasts. The AGM-induced expression of fibronectin and α-SMA was blocked by a TGF-β signal inhibitor but neither the stimulation of cell growth nor migration. These results imply that AGM activates normal fibroblasts by TGF-β-dependent and independent mechanisms. These findings also suggest that AGM and TGF-β1 cooperatively or complementarily contribute to the stromal activation and connective tissue formation in human cancer tissues, contributing to tumor progression.

B lymphocytes promote lymphogenous metastasis of lymphoma and melanoma

The prognosis of patients with many types of cancers correlates with the degree of metastasis to regional lymph nodes (LNs) and vital organs. However, the mechanisms and route of cancer cell metastasis are still unclear. Previous studies determined that B-cell accumulation in tumor-draining LNs (TDLNs) induces lymphatic sinus growth (lymphangiogenesis) and increases lymph flow, which could actively promote tumor dissemination through the lymphatic system. Using young Eµ-c-Myc mice that feature LN B-cell expansion as hosts for tumor transplants, we show that subcutaneously implanted lymphomas or melanomas preferentially spread to TDLNs over non-TDLNs, thus demonstrating that these tumors initially metastasize through lymphatic rather than through hematogenous routes. In addition, the rate and amount of tumor dissemination is greater in Eµ-c-Myc mice versus wild-type hosts, which correlates with LN B-cell accumulation and lymphangiogenesis in Eµ-c-Myc hosts. The increased lymphatic dissemination in Eµ-c-Myc hosts is further associated with rapid hematogenous tumor spread of subcutaneously implanted lymphomas, suggesting that TDLN metastasis secondarily drives lymphoma spread to distant organs. In contrast, after intravenous tumor cell injection, spleen metastasis of lymphoma cells or lung metastasis of melanoma cells is similar in Eµ-c-Myc and wild-type hosts. These studies demonstrate that the effect of Eµ-c-Myc hosts to promote metastasis is limited to the lymphatic route of dissemination. TDLN B-cell accumulation, in association with lymphangiogenesis and increased lymph flow, thus significantly contributes to dissemination of lymphomas and solid tumors, providing new targets for therapeutic intervention to block metastasis.

Age, viral copy number, and immunosuppressive therapy affect the duration of norovirus RNA excretion in inpatients diagnosed with norovirus infection

Norovirus is one of the leading causes of acute gastroenteritis worldwide. Although it is becoming clear that viral excretion in the stool continues even after the clinical symptoms have disappeared, the factors that determine its duration remain unknown. Between 2007 and 2009, all inpatients and medical staff at our hospital who showed symptoms of a new onset of gastroenteritis were asked to submit a sample for norovirus testing by real-time RT-PCR. One of the 273 patients included tested positive for GI norovirus, and a further 89 were positive for GII norovirus. Of these 90 norovirus-positive individuals, 76% excreted norovirus RNA in the stool for more than 7 days. The inpatient group contained more long shedders than the medical staff group (5/32 versus 1/39, P<0.05). The median viral shedding duration was 19.3 and 15.2 days for inpatients and medical staff, respectively. Among hospitalized patients, younger individuals, those with a higher viral copy number, and individuals receiving immunosuppressive therapy tended to require a longer time to eliminate the virus. These patients should therefore be monitored and managed carefully to prevent nosocomial spread of the disease.

Lymphatic endothelial murine chloride channel calcium-activated 1 is a ligand for leukocyte LFA-1 and Mac-1

The lymphatic circulation mediates drainage of fluid and cells from the periphery through lymph nodes, facilitating immune detection of lymph-borne foreign Ags. The 10.1.1 mAb recognizes a lymphatic endothelial Ag, in this study purified by Ab-affinity chromatography. SDS-PAGE and mass spectrometry identified murine chloride channel calcium-activated 1 (mCLCA1) as the 10.1.1 Ag, a 90-kDa cell-surface protein expressed in lymphatic endothelium and stromal cells of spleen and thymus. The 10.1.1 Ab-affinity chromatography also purified LFA-1, an integrin that mediates leukocyte adhesion to endothelium. This mCLCA1-LFA-1 interaction has functional consequences, as lymphocyte adhesion to lymphatic endothelium was blocked by 10.1.1 Ab bound to endotheliumor by LFA-1 Ab bound to lymphocytes. Lymphocyte adhesion was increased by cytokine treatment of lymphatic endothelium in association with increased expression of ICAM-1, an endothelial surface protein that is also a ligand for LFA-1. By contrast, mCLCA1 expression and the relative contribution of mCLCA1 to lymphocyte adhesion were unaffected by cytokine activation, demonstrating that mCLCA1 and ICAM-1 interactions with LFA-1 are differentially regulated. mCLCA1 also bound to the LFA-1-related Mac-1 integrin that is preferentially expressed on leukocytes. mCLCA1-mediated adhesion of Mac-1- or LFA-1-expressing leukocytes to lymphatic vessels and lymph node lymphatic sinuses provides a target for investigation of lymphatic involvement in leukocyte adhesion and trafficking during the immune response.

Decreased pregnancy rate is linked to abnormal uterine peristalsis caused by intramural fibroids

BACKGROUND

The relationship between fibroids and infertility remains an unsolved question, and management of intramural fibroids is controversial. During the implantation phase, uterine peristalsis is dramatically reduced, which is thought to facilitate embryo implantation. Our aims were to evaluate (i) the occurrence and frequency of uterine peristalsis in infertile women with intramural fibroids and (ii) whether the presence of uterine peristalsis decreases the pregnancy rate.

METHODS

Ninety-five infertile patients with uterine fibroids were examined using magnetic resonance imaging (MRI). Inclusion criteria were as follows: (i) presence of intramural fibroids, excluding submucosal type; (ii) no other significant infertility factors (excluding endometriosis); and (iii) regular menstrual cycles, and MRI performed at the time of implantation (luteal phase day 5-9). The frequency of junctional zone movement was evaluated using cine-mode-display MRI. After MRI, patients underwent infertility treatment for up to 4 months, and the pregnancy rate was evaluated prospectively.

RESULTS

Fifty-one patients fulfilled the inclusion criteria, and 29 (57%) and 22 (43%) patients were assigned to the low (0 or 1 time/3 min) or high frequency (≥ 2 times/3 min) uterine peristalsis group, respectively. Endometriosis incidence was the same in both groups. Ten out of the 29 patients (34%) in the low-frequency group achieved pregnancy, compared with none of the 22 patients (0%) in the high-frequency group (P< 0.005). Comparing pregnant and non-pregnant cases, 4 of 10 patients (40%) and 9 of 41 patients (22%), respectively, had endometriosis (not significant).

CONCLUSIONS

A higher frequency of uterine peristalsis during the mid-luteal phase might be one of the causes of infertility associated with intramural-type fibroids.

Interaction between survivin and aurora-B kinase plays an important role in survivin-mediated up-regulation of human telomerase reverse transcriptase expression

Survivin, a member of the apoptosis inhibitor family, shows increased expression in human cancers of various origins. It has been demonstrated that survivin inhibits apoptosis via caspase inhibition and promotes mitosis via aurora-B kinase activation. We recently reported that survivin enhances the expression of human telomerase reverse transcriptase (hTERT), a major determinant of telomerase activity in colon cancer cells. Survivin up-regulates hTERT expression by promoting the expression of specificity protein-1 (Sp1)- and c-Myc-mediated gene transcription via enhancing the phosphorylation of these transcriptional factors. However, the mechanism by which survivin regulates the phosphorylation of Sp1 and c-Myc is not well defined. In the present study, we hypothesized that survivin promotes the phosphorylation of Sp1 and c-Myc by activating aurora-B kinase. Inhibition of this enzyme by introducing small inhibitory RNA attenuated the phosphorylation of Sp1 and c-Myc and resulted in the abolition of the survivin effect on hTERT expression. In addition, blocking survivin phosphorylation at a threonine residue by inhibiting cyclin-dependent kinase 1 caused the dissociation of aurora-B kinase from survivin and attenuated the up-regulation of hTERT expression by survivin. Taken together, these results suggest that the interaction between survivin and aurora-B kinase may be essential for survivin to increase hTERT expression.

p19/Arf and p53 suppress sentinel lymph node lymphangiogenesis and carcinoma metastasis

The ability of tumor cells to metastasize is increasingly viewed as an interaction between the primary tumor and host tissues. Deletion of the p19/Arf or p53 tumor suppressor genes accelerates malignant progression and metastatic spread of 7,12-dimethylbenz(a)anthracene (DMBA)/12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced squamous cell carcinomas, providing a model system to address mechanisms of metastasis. Here, we show that benign pre-metastatic papillomas from wild-type mice trigger lymphangiogenesis within draining lymph nodes, whereas there is no growth of primary tumor lymphatic vessels. Lymph node lymphangiogenesis is greatly accelerated in papilloma-bearing p19/Arf- or p53-deficient mice, which coincides with the greater propensity of these tumors to progress to carcinomas and to metastasize. The extent of accumulation of B cells within the tumor-draining lymph nodes of wild-type mice predicted the level of lymph node lymphangiogenesis and metastatic potential. Arf or p53 deficiency strongly accelerated lymph node immune cell accumulation, in a manner that was associated with the extent of lymph node lymphatic sinus growth. This immune cell accumulation and lymph node lymphangiogenesis phenotype identifies host anti-tumor responses that could drive metastatic spread of cancers via the lymphatics.

GER1, a GDSL motif-encoding gene from rice is a novel early light- and jasmonate-induced gene

The reaction of the rice mutant HEBIBA differs from that of wild-type rice in that the mutant responds inversely to red light and is defective in the light-triggered biosynthesis of jasmonic acid (JA). Using the wild type and the HEBIBA mutant of rice in a differential display screen, we attempted to identify genes that act in or near the convergence point of light and JA signalling. We isolated specifically regulated DNA fragments from approximately 10 000 displayed bands, and identified a new early light- and JA-induced gene. This gene encodes an enzyme containing a GDSL motif, showing 38 % identity at the amino acid level to lipase Arab-1 in Arabidopsis thaliana. The GDSL CONTAINING ENZYME RICE 1 gene (GER1) is rapidly induced by both red (R) and far-red (FR) light and by JA. The results are discussed with respect to a possible role for GER1 as a negative regulator of coleoptile elongation in the context of recent findings on the impact of JA on light signalling.

Detailed images of asteroid 25143 Itokawa from Hayabusa

Rendezvous of the Japanese spacecraft Hayabusa with the near-Earth asteroid 25143 Itokawa took place during the interval September through November 2005. The onboard camera imaged the solid surface of this tiny asteroid (535 meters by 294 meters by 209 meters) with a spatial resolution of 70 centimeters per pixel, revealing diverse surface morphologies. Unlike previously explored asteroids, the surface of Itokawa reveals both rough and smooth terrains. Craters generally show unclear morphologies. Numerous boulders on Itokawa's surface suggest a rubble-pile structure.

Mutations of the p53 gene and loss of heterozygosity at chromosome 17p13.1 are associated with increased survivin expression in breast cancer

Expression of survivin, a member of the inhibitor-of-apoptosis (IAP) family, is elevated in fetal tissues and in various human cancers originating in the breast, lung, prostate, colon, pancreas, and stomach. Since overexpression of the survivin gene has been linked to poor patient survival in several cancers, survivin may be an important prognostic marker. Mechanisms up-regulating survivin gene expression in cancer are poorly understood. Recently, wild-type p53 was found to repress expression of the survivin gene by binding to the survivin promoter, thereby inhibiting promoter activity. Further, loss of heterozygosity (LOH) at 17p13 distal to the p53 gene is associated with more aggressive behavior of breast cancers. We therefore tested the hypothesis that not only p53 gene mutation but also LOH at 17p13 can up-regulate survivin expression in breast cancer. Survivin mRNA expression was greater in cancers than in uninvolved tissues (p < 0.0001). Mutations of the p53 gene were detected in 5 of 25 tumors; higher survivin gene expression was evident in these. LOH at the D17S938 locus (17p13.1) was found in 10 of 25 tumors, and most of these also showed increased survivin gene expression. Thus expression of survivin may be regulated not only by p53 but additionally by a putative tumor suppressor gene located at 17p13 distal to the p53 gene.

A novel aspartate protease gene, ALP56, is related to morphological features of colorectal adenomas

BACKGROUND AND AIMS

The recently identified aspartate protease gene ALP56 is up-regulated in human malignant tumors, including colorectal cancers, but the relationship remain unclear between ALP56 gene expression and clinicopathological findings, as well as when genetic alterations in ALP56 occur during the colorectal adenoma-carcinoma sequence. We therefore investigated expression of ALP56 mRNA in various human colorectal tissues.

MATERIALS AND METHODS

We examined 18 colorectal adenomas 22 cancers, and 24 adjacent normal mucosal samples from patients undergoing conventional resection or endoscopic mucosal resection. Expression of ALP56 mRNA was determined by quantitative reverse-transcription polymerase chain reaction.

RESULTS

Up-regulation of ALP56 gene transcription was observed in both adenomas and cancers compared to normal mucosa. ALP56 expression in exophytic adenomas was significantly greater than in flat adenomas.

CONCLUSION

ALP56 may contribute to colorectal adenoma formation and to an exophytic growth pattern in these adenomas.

PCD1, a novel gene containing PDZ and LIM domains, is overexpressed in human breast cancer and linked to lymph node metastasis

BACKGROUND

Despite surgical removal of the primary tumor of breast cancer in patients with apparently localized disease, relapse at local or distant sites may occur because undetectable micrometastases were present at the time of diagnosis. Identification of molecules associated with breast cancer metastasis suggests possible new treatments. PCD1, a gene encoding a new member of the PDZ and LIM domain-containing protein family, recently was identified. We examined the relationships between PCD1 mRNA expression in breast cancers and metastasis.

MATERIALS AND METHODS

PCD1 mRNA expression in breast cancer tissues was examined using a quantitative reverse transcription polymerase chain reaction.

RESULTS

PCD1 mRNA expression was greater in cancers than in noncancerous tissues (p < 0.0001). In addition, high PCD1 gene expression was more frequent in patients with lymph node metastasis.

CONCLUSION

PCD1 appears to contribute to breast cancer progression and nodal metastasis, thus representing a potential target molecule in breast cancer diagnosis and treatment.

A novel gene containing PDZ and LIM domains, PCD1, is overexpressed in human colorectal cancer

BACKGROUND

The process of colorectal cancer development involves accumulated genetic alterations affecting APC, K-ras and p53. A recently identified gene, PCD1, was reported to be up-regulated in human malignancies including colorectal cancers, but relationships between PCD1 gene expression and clinicopathological findings, as well as the timing of genetic alteration of PCD1 in colorectal cancer development, are not clear. To determine whether PCD1 contributes to colorectal cancer progression, we investigated the expression of PCD1 mRNA in human colorectal tissues.

MATERIALS AND METHODS

The expression of PCD1 mRNA was determined by quantitative RT-PCR. The mutation of p53 was detected by a PCR-SSCP method.

RESULTS

Up-regulation of PCD1 gene transcription was observed not in adenomas but in cancers compared to normal mucosa (p < 0.0001). Primary tumors with a mutation of p53 showed significantly greater PCD1 gene expression than tumors without such a mutation (p = 0.0134).

CONCLUSION

The PCD1 gene may play a role in colorectal cancer development from adenomas.

Selection of an internal control gene for quantitation of mRNA in colonic tissues

BACKGROUND

GAPDH, beta-actin and 18S rRNA are widely employed as internal control genes, with the assumption that they are expressed constitutively to similar degrees in different cells and tissues and under different experimental conditions. In this study, we tested this assumption by assessment of the transcription of these three genes in human colonic tissues using a quantitative RT-PCR.

RESULTS

GAPDH transcription was significantly greater in both colonic adenomas and cancers than in normal mucosa. In addition, transcription of beta-actin was significantly increased in cancers. The expression of 18S rRNA was essentially constant among these various tissues. Stable expression of 18S rRNA was observed during the growth of colonic cancer cells stimulated with serum, but both GAPDH and beta-actin transcription were up-regulated, coinciding with cell proliferation.

CONCLUSION

These results indicate that 18S rRNA is more reliable than GAPDH and beta-actin as an internal control gene for quantitative comparison of mRNA in colonic cancers.

Microbiological contamination in genetically modified animals and proposals for a microbiological test standard for national universities in Japan

The Biosafety Committee of the Japanese Association of Laboratory Animal Facilities of National Universities (JALAN) investigated recent episodes of microbiological contamination in genetically modified mice (GMM), and the countermeasures taken when the contaminated GMM were introduced into animal facilities, by questionnaires addressed to 53 animal facilities belonging to JALAN and serological tests. Although almost all of the contaminated GMM were accepted with conditions such as rederivation after or before reception and housing in designated rooms, contamination with a spectrum of microorganisms was demonstrated in GMM transferred domestically and from abroad. In serological tests, Mycoplasma pulmonis, mouse parvovirus, and mouse encephalomylitis virus were detected in GMM transferred from domestic facilities and from abroad. The present results of the questionnaires and serological tests suggest that GMM are highly and widely contaminated with microorganisms compared with mice from commercial breeders. Thus, we propose a microbiological requirement, including microbiological status--excellent, common, and minimum--as a guide for the transfer and procurement of mice and rats in Japan.

Analyses of matrix metalloproteinases and their inhibitors in cyst fluid of serous ovarian tumors

OBJECTIVES

Expression of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) in serous tumors of the ovary was investigated to determine whether and how these proteolytic enzymes are associated with the progression of these tumors.

METHODS

Cyst fluid of 24 serous ovarian tumors (8 adenocarcinomas, 2 borderline tumors and 14 adenomas) was analyzed using gelatin/casein zymography and enzyme-linked immunosorbent assay.

RESULTS

Concentrations of MMP-9 and MMP-2 were statistically higher in serous adenocarcinomas than in serous adenomas (p < 0.01, p < 0.05, respectively), while the concentrations of TIMP-1 and TIMP-2 showed no significant difference between adenocarcinomas and adenomas. The molar ratio of TIMP-2/MMP-2 was lower in adenocarcinomas than in adenomas (p < 0.05). With gelatin zymography, the MMP-9 band was detected in all serous adenocarcinomas, but only in 8 of 14 serous adenomas (p = 0.05). Using casein zymography, MMP-7 was more frequently detected in serous adenocarcinomas (7/8) than in serous adenomas (4/14; p < 0.05).

CONCLUSIONS

These observations indicate that matriolytic enzymes such as MMP-2, MMP-7 and MMP-9 are secreted into cyst fluid from serous adenocarcinoma tissues. In part, the aggressive invasion of serous carcinoma cells may be explained by the expression of matriolytic enzymes.

Detection of species of the subgenus Leishmania parasites using polymerase chain reaction and southern blotting

In this study, an attempt was made to identify different Leishmania species by polymerase chain reaction (PCR). Fourteen Leishmania strains from stock were tested by PCR and Southern blotting. A pair of primers were employed that anneal to the kinetoplast DNA sequence conserved among subgenus Leishmania. Of the 14 Leishmania strains used in this study, six showed strong bands of approximately 170 bp, and all the positive strains belonged to the species of the subgenus Leishmania viz., Leishmania (Leishmania) garnhami, L. (L.) amazonensis, L. (L.) pifanoi, L. (L.) mexicana, L. (L.) chagasi, and L. (L.) major All the species belonging to the subgenus Viannia used in this study were negative by PCR. These results suggest that the primer pair may be useful for identification of the species belonging to the subgenus Leishmania of the New World as well as to distinguish subgenus Leishmania from subgenus Viannia.

Technical advance: an automated device for cryofixation of specimens of electron microscopy using liquid helium

Metal-contact rapid freezing using liquid helium is theoretically the best method for preserving the fine structure of living cells with high temporal resolution in preparation of tissue samples for electron microscopy. However, this method is not commonly used, because of its technical difficulty and low reproducibility. We have designed and constructed an automatic device which allows simple, rapid and reproducible preparation of high-quality electron microscopic specimens by the non-specialist. We assessed the quality of cryofixation in samples prepared using this device by examining the preservation of cellular ultrastructure in relation to distance from the freezing block, and found that the region within 10 microm of the metal-contact plane was fixed with the highest quality. We applied this device, in combination with freeze-substitution methods and immunocytochemical techniques, to two phenomena involving rapid movement of subcellular components: (1) active movement of subcellular structures in the papillar cells of stigma and (2) light-induced rapid subcellular translocation of phytochrome A. Considering the importance of understanding subcellular processes of living cells for molecular and cell biology, this device will be a useful tool for diverse biological applications in the near future.

Clinical and pharmacological studies on liver diseases treated with Kampo herbal medicine

Hepatitis C virus (HCV) infection frequently causes chronic hepatitis, which is linked to the development of liver cirrhosis and hepatocellular carcinoma. Most physicians who practice Kampo medicine in Japan have observed that Kampo medicine can be as effective as interferon therapy in the treatment of chronic hepatitis C. In the present study, to evaluate the effect of Kampo medicine on chronic hepatitis C, clinical treatment was assessed in short-term and long-term study, and it was shown that ninjin-yoei-to (Formula ginseng compositae: TJ-108) was very effective. Therefore, to find the most active herbal component of TJ-108 in the treatment of HCV, Citrus Unshiu Peel, Schisandra Fruit, and Polygala Root, which are specific to TJ-108, were screened using an in vitro HCV infection model. Among the three herbs, Schisandra Fruit was found to be most active. In the next step, Gomisin A, an active component of Schisandra Fruit, was studied using an in vitro model with MOLT-4 cells and an animal model of immunologically induced acute hepatic failures. It is concluded that the therapeutic effect of TJ-108 on chronic hepatitis C is from the inhibitory effect on HCV infection, and also from the protective effect on immunological hepatopathy of Schisandra Fruit and its lignan component, Gomisin A.

Discovery of a non-peptide small molecule that selectively mimics the biological actions of calcitonin

Calcitonin (CT), a 32-amino acid peptide hormone secreted mainly from the thyroid gland, plays an important role in maintaining bone homeostasis. To discover non-peptide small molecules with biological actions similar to those of CT, a cell-based screening of an in-house chemical library was performed and a pyridone derivative (SUN B8155) was identified. Like CT, it elevated cyclic AMP (cAMP) levels in T47D and UMR106-06 cells which endogenously express human and rat CT receptor, respectively. SUN B8155 also stimulated cAMP formation in cells expressing recombinant human CT receptor, but not in those expressing human parathyroid hormone/parathyroid hormone-related peptide receptor. Accumulation of cAMP in T47D cells was blocked by a selective antagonist of CT receptor, salmon CT(8-32), whereas SUN B8155 did not displace the specific binding of [(125)I]CT to the receptor. Our results suggested that the compound selectively interacts with the CT receptor by a mechanism similar to but probably different from that of CT itself. In rats, intraperitoneal administration of SUN B8155 significantly lowered serum calcium levels, like CT. Our results demonstrate, for the first time, that the biological activities of the newly identified small molecule can mimic that of CT, acting via the CT receptor.

Evidence for type II phytochrome-induced rapid signalling leading to cab::luciferase gene expression in tobacco cotyledons

We studied the activation of cab gene expression by phytochrome-induced intercellular signalling and report insights into the mechanism of induction and outspread of a plant internal signal. By micro-beam irradiation techniques and use of a photon-imaging charge-coupled device (CCD) camera system we monitored cab::luciferase reporter gene expression in cotyledons of transgenic tobacco (Nicotiana tabacum L. cv. Xanthi) plants. We found that (i) the photoreceptor triggering intercellular signalling and reporter-gene expression is type II but not type I phytochrome, (ii) phytochrome in its far-red-absorbing (Pfr) form is necessary for the induction but not for the outspread of the signalling, (iii) red/far-red reversibility is restricted to the red-irradiated cells, and (iv) the phytochrome-induced signal spreads rapidly throughout the cotyledon and reaches its target cells within minutes.