Prognostic impact of nodal status and lymphovascular invasion in patients undergoing neoadjuvant chemotherapy for esophageal squamous cell carcinoma

Nodal status is well known to be the most important prognostic factor for esophageal cancer patients, even if they are treated with neoadjuvant therapy. To establish an optimal postoperative adjuvant strategy for patients, we aimed to more accurately predict the prognosis of patients and systemic recurrence by using clinicopathological factors, including nodal status, in patients with esophageal cancer who received neoadjuvant chemotherapy. The clinicopathological factors associated with survival and systemic recurrence were investigated in 488 patients with esophageal squamous cell carcinoma who received neoadjuvant chemotherapy. Overall survival differed according to tumor depth, nodal status, tumor regression, and lymphovascular (LV) invasion. In the multivariate analysis, nodal status and LV invasion were identified as independent prognostic factors (P < 0.0001, P = 0.0008). Nodal status was also identified as an independent factor associated with systemic recurrence, although LV invasion was a borderline factor (P = 0.066). In each pN stage, patients with LV invasion showed significantly worse overall survival than those without LV invasion (pN0: P = 0.036, pN1: P = 0.0044, pN2: P = 0.0194, pN3: P = 0.0054). Patients with LV invasion were also more likely to have systemic, and any recurrence than those without LV invasion in each pN stage. Pathological nodal status and LV invasion were the most important predictors of survival and systemic recurrence in patients with esophageal cancer who underwent neoadjuvant chemotherapy followed by surgery. This finding could provide useful information about selecting candidates for adjuvant therapy among these patients. Our analysis showed that LV invasion was an independent prognostic factor in patients with esophageal cancer who underwent neoadjuvant chemotherapy and that combining LV invasion with pathological nodal status makes it possible to stratify the prognosis in those patients.

Real-world prevalence of programmed death ligand 1 expression in locally advanced or metastatic non-small-cell lung cancer: The global, multicenter EXPRESS study

OBJECTIVES

Tumor programmed death ligand 1 (PD-L1) expression is associated with improved clinical benefit from immunotherapies targeting the PD-1 pathway. We conducted a global, multicenter, retrospective observational study to determine real-world prevalence of tumor PD-L1 expression in patients with NSCLC.

MATERIALS AND METHODS

Patients ≥18 years with histologically confirmed stage IIIB/IV NSCLC and a tumor tissue block (≤5 years old) obtained before treatment were identified in 45 centers across 18 countries. Tumor samples from eligible patients were selected consecutively, when possible. PD-L1 expression was evaluated at each center using the PD-L1 IHC 22C3 pharmDx kit (Agilent, Santa Clara, CA, USA).

RESULTS

Of 2617 patients who met inclusion criteria, 2368 (90%) had PD-L1 data; 530 (22%) patients had PD-L1 TPS ≥ 50%, 1232 (52%) had PD-L1 TPS ≥ 1%, and 1136 (48%) had PD-L1 TPS < 1%. The most common reason for not having PD-L1 data (n = 249) was insufficient tumor cells (<100) on the slide (n = 170 [6%]). Percentages of patients with PD-L1 TPS ≥ 50% and TPS ≥ 1%, respectively were: 22%/52% in Europe; 22%/53% in Asia Pacific; 21%/47% in the Americas, and 24%/55% in other countries. Prevalence of EGFR mutations (19%) and ALK alterations (3%) was consistent with prior reports from metastatic NSCLC studies. Among 1064 patients negative for both EGFR mutation and ALK alteration, the percentage with PD-L1 TPS ≥ 50% and TPS ≥ 1%, respectively, were 27% and 53%.

CONCLUSIONS

This is the largest real-world study in advanced NSCLC to date evaluating PD-L1 tumor expression using the 22C3 pharmDx kit. Testing failure rate was low with local evaluation of PD-L1 TPS across a large number of centers. Prevalence of PD-L1 TPS ≥ 50% and TPS ≥ 1% among patients with stage IIIB/IV NSCLC was similar across geographic regions and broadly consistent with central testing results from clinical trial screening populations.

Appropriate management of high-flow priapism based on color Doppler ultrasonography findings in pediatric patients: four case reports and a review of the literature

INTRODUCTION

High-flow priapism in children is a very rare condition, and there is no clear consensus on its management. High-flow priapism is associated with increased cavernosal blood flow and broadly divided into two groups based on the presence or absence of arteriocavernous fistula in the corpora cavernosa.

OBJECTIVE

This study aimed to determine the appropriate management of high-flow priapism based on the existence of arteriocavernous fistula using penile color Doppler ultrasonography (CDU) findings in the pediatric population.

STUDY DESIGN

The cases of four boys aged between 6 and 11 years with high-flow priapism treated between 2009 and 2017 are reported. Two boys had prior perineal trauma, one boy had blunt penile glans trauma, and one had no obvious cause for the condition. All boys initially underwent penile CDU and were treated conservatively or via selective arterial embolization depending upon the presence or absence of an arteriocavernous fistula.

RESULTS

Penile CDU revealed an arteriocavernous fistula inside the corpus cavernosum penis in two of four boys and increased blood flow inside the corpus spongiosum in the remaining boys. The former two boys underwent selective arterial embolization and one boy underwent repeated embolization because of remaining arteriocavernous fistula feeding from the contralateral cavernosal artery, whereas the boys with no arteriocavernous fistula on CDU were managed conservatively. All boys were successfully treated within 1 month, and they had normal morning erection and no evidence of recurrent priapism at the follow-up.

DISCUSSION

Unlike low-flow priapism, high-flow priapism is not a medical emergency. Therefore, conservative therapy is an appropriate initial treatment, although selective arterial embolization can be effective for high-flow priapism with arteriocavernous fistula, with a success rate of 97% and no reported complications to date. Penile CDU is an imaging technique that can detect focal areas of turbulent flow with sensitivity close to 100%. This study has several limitations including a small number of cases, limited follow-up duration, and possibility of spontaneous arteriocavernous fistula closure in cases treated by arterial embolization.

CONCLUSION

Penile CDU could be a reliable tool to diagnose high-flow priapism and detect the presence or absence of arteriocavernous fistula. Although conservative therapy remains the first choice, selective arterial embolization may be an early treatment option when CDU reveals an arteriocavernous fistula.

Development of an Immunochromatography Assay (QuickNavi-Ebola) to Detect Multiple Species of Ebolaviruses

The latest outbreak of Ebola virus disease (EVD) in West Africa has highlighted the urgent need for the development of rapid and reliable diagnostic assays. We used monoclonal antibodies specific to the ebolavirus nucleoprotein to develop an immunochromatography (IC) assay (QuickNavi-Ebola) for rapid diagnosis of EVD. The IC assay was first evaluated with tissue culture supernatants of infected Vero E6 cells and found to be capable of detecting 10³-10⁴ focus-forming units/mL of ebolaviruses. Using serum samples from experimentally infected nonhuman primates, we confirmed that the assay could detect the viral antigen shortly after disease onset. It was also noted that multiple species of ebolaviruses could be detected by the IC assay. Owing to the simplicity of the assay procedure and absence of requirements for special equipment and training, QuickNavi-Ebola is expected to be a useful tool for rapid diagnosis of EVD.

Novel prognostic prediction models for patients with stage IV colorectal cancer after concurrent curative resection

BACKGROUND

We developed a prediction tool for recurrence and survival in patients with stage IV colorectal cancer (CRC) following surgically curative resection.

PATIENTS AND METHODS

From January 1983 to December 2012, 113 patients with CRC and synchronous liver and/or lung metastatic CRC were investigated at the Osaka Medical Center for Cancer and Cardiovascular Diseases. All patients underwent curative resection of primary and metastatic lesions. In the group of patients who underwent surgery from 1983 to 2008, a Cox regression model was used to develop prediction models for 1-year, 3-year and 5-year cancer-specific survival (CSS) and relapse-free survival (RFS). In the other group of patients who underwent surgery from 2009 to 2012, the developed prediction model was validated.

RESULTS

Univariate analysis of clinicopathological factors showed that the following factors were significantly correlated with CSS and RFS: preoperative serum carcinoembryonic antigen level, tumour location, pathologically defined tumour invasion and lymph node metastasis, and synchronous metastatic lesions. Using these variables, novel prediction models predicting CSS and RFS were constructed using the Cox regression model with concordance indexes of 0.802 for CSS and 0.631 for RFS. The prediction models were validated by external data sets in an independent patient group.

CONCLUSIONS

We developed novel and reliable personalised prognostic models, integrating tumour, node, metastasis (TNM) factors as well as the preoperative serum carcinoembryonic antigen level, tumour location and metastatic lesions, to predict patients' prognosis following surgically curative resection. This individualised prediction model may help clinicians in the treatment of postoperative stage IV CRC following surgically curative resection.

The correlation of antibodies to nuclear ribonucleoprotein (RNP) and nuclear acidic protein (Sm) with nephritis in patients with systemic lupus erythematosus (SLE)

The role of antibodies to Sm and RNP in renal diseases in SLE was investigated using counter immunoelectrophoresis (CIE). Antibody to RNP was found in about 50% of lupus patients irrespective of the degree of renal involvement as evaluated clinically, histologically and immunopathologically. Antibody to Sm was found more frequently in lupus patients with renal lesions than in those without renal disease. Antibody to RNP was demonstrated in 8 of 10 (80%) and antibody to Sm in 4 of 10 (40%) specimens obtained by elution of autopsied kidneys. These results suggest that antibodies to RNP and Sm are also of importance in the pathogenesis of lupus nephritis in addition to the already recognized role of antibody to ds-DNA.

Anatomical versus non-anatomical resection for hepatocellular carcinoma

BACKGROUND

The optimal surgical resection method in patients with HCC to minimize the risk of local recurrence has not yet been determined. The aim of this study was to compare the prognosis following anatomical versus non-anatomical hepatic resection for hepatocellular carcinoma (HCC).

METHODS

Consecutive patients with HCC without macroscopic vascular invasion, treated by curative resection between 1981 and 2012 at Osaka Medical Centre, were included in this retrospective study. The outcomes of patients selected by propensity score matching were compared.

RESULTS

Some 1102 patients were included, 577 in the anatomical and 525 in the non-anatomical resection group. By propensity score matching, 329 patients were selected into each group. Demographic, preoperative and tumour variables were similar between the propensity score-matched groups, including tumour size, tumour multiplicity, α-fetoprotein level and 15-min indocyanine green retention rate at 15 min. The incidence of microvascular invasion was higher in the matched anatomical resection group (P = 0·048). Stratified analysis of recurrence-free and overall survival rates revealed no statistically significant differences between the two propensity score-matched groups (P = 0·704 and P = 0·381 respectively). There was also no significant difference in the early recurrence rate within 2 years after resection between these groups (P = 0·726). Subset analysis of the early recurrence-free survival rate in patients with and without microvascular invasion revealed no significant differences between the groups (P = 0·312 and P = 0·479 respectively).

CONCLUSION

The resection method had no impact on the risk of HCC recurrence or survival.

miR-320c regulates gemcitabine-resistance in pancreatic cancer via SMARCC1

Background:

Gemcitabine-based chemotherapy is the standard treatment for pancreatic cancer. However, the issue of resistance remains unresolved. The aim of this study was to identify microRNAs (miRNAs) that govern the resistance to gemcitabine in pancreatic cancer.

Methods:

miRNA microarray analysis using gemcitabine-resistant clones of MiaPaCa2 (MiaPaCa2-RGs), PSN1 (PSN1-RGs), and their parental cells (MiaPaCa2-P, PSN1-P) was conducted. Changes in the anti-cancer effects of gemcitabine were studied after gain/loss-of-function analysis of the candidate miRNA. Further assessment of the putative target gene was performed in vitro and in 66 pancreatic cancer clinical samples.

Results:

miR-320c expression was significantly higher in MiaPaCa2-RGs and PSN1-RGs than in their parental cells. miR-320c induced resistance to gemcitabine in MiaPaCa2. Further experiments showed that miR-320c-related resistance to gemcitabine was mediated through SMARCC1, a core subunit of the switch/sucrose nonfermentable (SWI/SNF) chromatin remodeling complex. In addition, clinical examination revealed that only SMARCC1-positive patients benefited from gemcitabine therapy with regard to survival after recurrence (P=0.0463).

Conclusion:

The results indicate that miR-320c regulates the resistance of pancreatic cancer cells to gemcitabine through SMARCC1, suggesting that miR-320c/SMARCC1 could be suitable for prediction of the clinical response and potential therapeutic target in pancreatic cancer patients on gemcitabine-based therapy.

Abstract P4-04-08: A Potential non-viral vector to transfect dendritic cell and thereby MHC-Class I antigen presentation might be a potential use in carcinoma

To date almost no remarkable potential non-viral vector was developed to transfect promisingly primary dendritic cell like Bone Marrow Derived Dendritic Cell (BMDC) so that it might generate antigen presentation while epitopic-plasmid was delivered. Here we have introduced a potential non-viral vector named Stearyl-KALA MEND (100–130 nm, zeta potential 35–40 mV), which expressed to date the highest transgene expression while firefly luciferase was introduced (sub-cloned), and thereby promising antigen presentation in vitro while OVA plasmid containing MHC Class-I restricted SIINFEKL epitope was introduced and co-cultured with B3Z T-cell hybridoma. On the basis of these results, we used this vector to transfect BMDC and harvested the DC to chase the corresponding EG7-OVA induced tumor ex vivo. Later we further immunized mice directly with STR-KALA MEND containing OVA plasmid and challenged against the tumor (EG7-OVA induced). In this in vivo study we found also a significant antitumor activity. To evaluate the promptness of our vector we further sub-cloned Mart-1 gene, in our sub-cloned plasmid vector and immunized the mice as before. Thereafter inserting B16F10 melanoma cells to the immunized mice we found also a significant antitumor activity after 24 days of inoculation. Thus the vector, STR-KALA MEND might be a future potential use as DNA vaccine in anti-tumor methodology.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-04-08.

The flow cytometric nuclear-DNA content, tumor-origin, nuclear size and prognosis in squamous-cell lung-cancer

We examined the relationships among nuclear DNA content, tumor origin, nuclear size, and prognosis in squamous cell lung cancer. Central tumors had significantly higher DNA aneuploidy (83%, p<0.01) and DNA indices (1.65+/-0.40, p<0.01) than did peripheral tumors (40%, 1.29+/-0.37, respectively). All six women in the study (five no smokers) had peripheral diploid tumors. Patients (15) with diploid tumors had significantly longer survival times (a 5-year survival rate of 63%) than did those (28) with aneuploid tumors (29%, p<0.01). Patients with tumors having both large nuclei (nuclei greater than 11 mum in mean diameter) and a DNA index of 1.0 had the longest survival times (a 5-year survival rate of 100%). This was followed by patients with large-nucleus tumors and a DNA index of more than 1.51 (71%). However, all patients with small-nucleus tumors (tumors with nuclei less than 10 mum in mean diameter) and a DNA index of more than 1.51 died within 30 months. These results suggested that the malignancy level of squamous cell lung cancer and the prognosis could be determined by studying the DNA content and the size of the tumor nuclei, and that there may be differences in the pathogenesis and/or malignancy of central and peripheral tumors.

A multifunctional envelope-type nanodevice for use in nanomedicine: concept and applications

In the 21st century, drug development has shifted toward larger molecules such as proteins and nucleic acids, which require the use of new chemical strategies. In this process, the drug delivery system plays a central role and intracellular targeting using nanotechnology has become a key technology for the development of successful new medicines. We have developed a new delivery system, a multifunctional envelope-type nanodevice (MEND) based on "Programmed Packaging." In this new concept of packaging, multifunctional nanodevices are integrated into a nanocarrier system according to a program designed to overcome all barriers during the course of biodistribution and intracellular trafficking. In this Account, we introduce our method for delivering nucleic acids or proteins to intracellular sites of action such as the cytosol, nucleus, and mitochondria and for targeting selective tissues in vivo via systemic administration of the nanodevices. First, we introduce an octaarginine-modified MEND (R8-MEND) as an efficient intracellular delivery system, designed especially for vaccinations and transgene expression. Many types of cells can internalize the R8-MEND, mainly by inducing macropinocytosis, and the MEND escapes from macropinosomes via membrane fusion, which leads to efficient antigen presentation via the major histocompatibility complex I pathway in antigen-presenting cells. In addition, the transfection activities of the R8-MEND in dividing cells, such as HeLa or A549 cells, are as high as those for adenovirus. However, because the R8-MEND cannot induce sufficient transgene activity in primary cultured dendritic cells, which are critical regulators of the immune response, we converted the R8-MEND into a tetralamellar MEND (T-MEND). The T-MEND uses a new packaging method and delivers condensed pDNA into the nucleus via fusion between the envelopes and the nuclear membrane. To achieve efficient transfection activity, we also optimized the decondensation of nucleic acids within the nucleus. To optimize mitochondrial drug delivery, we introduced the MITOPorter. Many types of materials can be packaged into this liposome-based nanocarrier and then delivered to mitochondria via membrane fusion mechanisms. Finally, we describe an integrated strategy for in vivo tumor delivery and optimization of intracellular trafficking. Successful tumor delivery typically requires coating the surfaces of nanoparticles with PEG, but PEG can also limit uptake by the reticuloendothelial system and reduce the efficiency of intracellular trafficking. Here we integrate the optimum biodistribution and intracellular trafficking of the MEND with an innovative strategy such as enzymatically cleavable PEG and a short membrane peptide, GALA. Some of these strategies will soon be tested in the clinic.

Ep-CAM is a significant prognostic factor in pancreatic cancer patients by suppressing cell activity

The identification of molecular markers useful for predicting prognosis in pancreatic cancer patients is crucial for advances in disease management. The epithelial cell adhesion molecule (Ep-CAM) is known to express in most epithelial malignancies and was reported as a tumor marker or a candidate of molecular targeting therapy. However, the clinical significance of Ep-CAM expression in pancreatic cancer is not well-known. We determined the difference of malignant potential between parental and Ep-CAM-transfected pancreatic cancer cell lines by using proliferation, invasion and migration assay. Furthermore, we determined the relationship between tumoral Ep-CAM expression of resected specimens and clinical prognosis in 95 pancreatic cancer patients receiving radical surgery at two different cancer centers. One of the three Ep-CAM-transfected cell lines showed significantly low proliferation rate compared with the parental cell, while there was no difference in the other two cell lines. In invasion and migration assays, Ep-CAM-transfected cells showed significantly lower malignant potential than parental in all of the three cell lines. In 95 pancreatic cancer patients, 47 patients showed high-Ep-CAM expression, while 48 patients showed low, and there was no difference of clinicopathological features between Ep-CAM high and low-expression group. High-Ep-CAM expression group showed significantly good prognosis in overall survival (3-year survival; 56.2 versus 19.2%, P=0.0018) as well as in disease-free survival (3-year survival; 40.3 versus 14.4%, P=0.038) compared with low-expression group. In addition, the impact of Ep-CAM was observed strongly in LN-negative group when the influence of Ep-CAM was examined with dividing patients into LN-positive and negative group. In multivariate analysis, Ep-CAM expression was one of the independent prognostic factors as well as histology and lymph node metastasis. Ep-CAM expression was found to be related to the suppression of pancreatic cancer cell activity and the good prognosis in pancreatic cancer patients receiving the curative resection.

Enhanced inhibitory effects of TBT chloride on the development of F1 rats

Neurotoxicity is one of the major effects of tributyltin (TBT). The effects on the next generation of F(1) rats exposed to TBT via the placenta and their dams' milk may be stronger than those on adults. Pregnant Wister rats were exposed to TBT at 0 and 125 ppm in their food. Half of the female F(1) rats in both groups were exposed to TBT at 125 ppm in their food from 9 to 15 weeks of age. Female F(1) rats were divided into the following groups: the control-control (CC) group, with no exposure; the TBT-control (TC) group, exposed to TBT via the placenta and their dams' milk; the control-TBT (CT) group, exposed to TBT via their food from 9 to 15 weeks of age; and the TBT-TBT (TT) group, exposed to TBT via the placenta, their dams' milk, and their food (n = 10/group). After administration, an open-field test and prepulse inhibition (PPI) test were performed at 15 weeks of age. The mean body weights of the TC and TT groups were significantly lower than that of the CC group from 9 to 15 weeks of age. The mean relative thymus weight of the TC and TT groups was significantly lower than that of the CC group. In the open-field test, a marked decrease in the total locomotion distance was observed in the TT group. The mean values in the TT and TC groups were significantly lower than that in the CC group. For the locomotion distance between 15 and 20 min, the mean values in the CT, TC, and TT groups were significantly lower than that in the CC group. The mean locomotor distance between 25 and 30 min in the TT group was significantly lower than that in the CC and TC groups. The mean values of instances of wall rearing in the TC, CT, and TT groups were significantly lower than that in the CC group. The mean value of face washing or body washing in the TT group was significantly lower than that in the CT group. There were no significant differences in indexes of the PPI test. Exposure to TBT via the placenta and their dams' milk inhibited the development of F(1) rats, which continued after weaning. Inhibition of the rats' activity induced by exposure to TBT via the placenta and their dams' milk and/or via their food was suggested. The effects were most evident in the TT group.

Disparity between serotonin- and acetylcholine-provoked coronary artery spasm

BACKGROUND AND HYPOTHESIS

Intrinsic vasoactive substances, such as serotonin and acetylcholine, are known to provoke coronary artery spasm in patients with vasospastic angina. It remains unclear, however, whether these different agents, which activate different receptors, produce spasms at the same sites in these patients. The present study was designed to clarify the disparity of receptor agonist-induced coronary artery spasms in the same patients.

METHODS

We conducted sequential provocative tests of coronary artery spasm by acetylcholine, serotonin, and ergonovine in 20 patients with rest angina examined with quantitative coronary angiography.

RESULTS

Coronary artery spasms were provoked in all patients at 27 spastic sites. In 13 patients, ergonovine provoked spasms and in 10 of 13 patients who were diagnosed with variant angina, both acetylcholine and serotonin provoked spasms at the same sites where ergonovine also did. In 4 of 13 patients, spasms were provoked by serotonin but not by acetylcholine. In the remaining seven patients, whose spasms were induced by ergonovine, spasms were produced by acetylcholine but not by serotonin. On coronary angiography, the spastic sites for both acetylcholine and serotonin, and those for serotonin alone, were located in the proximal segments of coronary arteries, whereas the spastic sites for acetylcholine alone were located in the distal segments.

CONCLUSIONS

This study documented the disparity between serotonin- and acetylcholine-induced spasms. Provocative tests using agents that activate different receptors may produce coronary artery spasms at the same and/or different sites, and this disparity may reflect the clinical heterogeneity of vasospastic ischemic syndrome.

Octaarginine-modified multifunctional envelope-type nanoparticles for gene delivery

This study describes a multifunctional envelope-type nano device (MEND) that mimics an envelope-type virus based on a novel packaging strategy. MEND particles contain a DNA core packaged into a lipid envelope modified with an octaarginine peptide. The peptide mediates internalization via macropinocytosis, which avoids lysosomal degradation. MEND-mediated transfection of a luciferase expression plasmid achieved comparable efficiency to adenovirus-mediated transfection, with lower associated cytotoxicity. Furthermore, topical application of MEND particles containing constitutively active bone morphogenetic protein (BMP) type IA receptor (caBmpr1a) gene had a significant impact on hair growth in vivo. These data demonstrate that MEND is a promising non-viral gene delivery system that may provide superior results to existing non-viral gene delivery technologies.

Development of a novel systemic gene delivery system for cancer therapy with a tumor-specific cleavable PEG-lipid

For successful cancer gene therapy via intravenous (i.v.) administration, it is essential to optimize the stability of carriers in the systemic circulation and the cellular association after the accumulation of the carrier in tumor tissue. However, a dilemma exists regarding the use of poly(ethylene glycol) (PEG), which is useful for conferring stability in the systemic circulation, but is undesirable for the cellular uptake and the following processes. We report the development of a PEG-peptide-lipid ternary conjugate (PEG-Peptide-DOPE conjugate (PPD)). In this strategy, the PEG is removed from the carriers via cleavage by a matrix metalloproteinase (MMP), which is specifically expressed in tumor tissues. An in vitro study revealed that the PPD-modified gene carrier (Multifunctional Envelope-type Nano Device: MEND) exhibited pDNA expression activity that was dependent on the MMP expression level in the host cells. In vivo studies further revealed that the PPD was potent in stabilizing MEND in the systemic circulation and facilitating tumor accumulation. Moreover, the i.v. administration of PPD or PEG/PPD dually-modified MEND resulted in the stimulation of pDNA expression in tumor tissue, as compared with a conventional PEG-modified MEND. Thus, MEND modified with PPD is a promising device, which has the potential to make in vivo cancer gene therapy achievable.

Phase II clinical study of combination therapy with irinotecan and S-1(IRIS) for inoperable recurrent advanced colorectal cancer: Hokkaido Gastrointestinal Cancer Study Group study HGCSG-0302)

3589

Background: We planned to conduct a phase II clinical study of combination therapy with irinotecan and S-1, a new oral anticancer drug of the fluorinated pyrimidine type. We reported the interium reports of this study in colorectal cancer patients at GI cancer Symposium 2006. Methods: The antitumor effect was the primary endpoint, while the safety, progression-free survival time, and median survival time were the secondary endpoints. The subjects were untreated patients with inoperable advanced colorectal cancer aged 20–75 years. Irinotecan was administered at a dose of 100 mg/m2 (on days 1 and 15) as an intravenous infusion over 90 minutes, and oral S-1 (40 mg/m2) was administered after breakfast and dinner and then withdrawn for 2 weeks. Results: Forty patients were enrolled in the present study. There were 23 men and 17 women. The median age was 62 years (range: 34 to 74 years). Two patient showed grade 4 neutropenia, but the next course could be given safely after dose reduction. Three patients had grade 3 diarrhea, but therapy could be continued with addition of an antidiarrheal drug. No other serious adverse reactions occurred (either hematological or non-hematological), and all patients could receive therapy safely on an outpatient basis. Interim analysis suggested excellent results, with a response rate of 50%. To date, 231 cycles (median 8, range 1–19) have been administered. Median relative dose intensity was 97% for S-1 and 87% for irinotecan. 36 pts are evaluable for efficacy: RR was 47.2% (95% CI, 30.9–63.5%) and Disease Control Rate (PR + SD) was seen in 94.4% of pts. PFS of this regimen is 320 days. MST is not reached. Conclusions: IRIS therapy achieved a high response rate and could be given safely. These findings suggest that the therapy has potential as first-line treatment for inoperable advanced recurrent colorectal cancer. It seems that IRIS is a good treatment equal to FOLFIRI. In addition, this regimen could qualify as a candidate for future combination therapy with a molecular-targeting drug. The latest data will be reported at the meeting.

No significant financial relationships to disclose.

Identification of an actin-binding site in p47phoxan organizer protein of NADPH oxidase

Actin has been reported to enhance the superoxide-generating activity of neutrophil NADPH oxidase in a cell-free system and to interact with p47phox, a regulatory subunit of the oxidase. In the present study, we searched for an actin-binding site in p47phox by far-western blotting and blot-binding assays using truncated forms of p47phox. The amino-acid sequence 319-337 was identified as an actin-binding site, and a synthetic peptide of this sequence bound to actin. The sequence shows no homology to other known actin-binding motifs. It is located in the autoinhibitory region of p47phox and includes Ser-328, a phosphorylation site essential for unmasking. Although a phosphorylation-mimetic p47phox mutant bound to actin with a lower affinity than the wild type, the same mutant interacted with filamentous actin more efficiently than the wild type. A mutant peptide p47phox (319-337, Ser328Glu) bound to filamentous actin more tightly than to monomer actin. These results suggest that p47phox moves to cortical actin when it becomes unmasked in the cells.

Atopic dermatitis-like symptoms in HR-1 hairless mice fed a diet low in magnesium and zinc

We aimed to develop an animal model for atopic dermatitis. HR-1 hairless mice fed a diet with reduced magnesium and zinc levels were compared with mice fed a standard diet. Skin dryness and wrinkle-like changes, scratching behaviour, decreased skin water content, increased transepidermal water loss and raised blood immunoglobulin E levels were seen in the group receiving the reduced magnesium and zinc diet compared with control mice. There were no significant differences in body weight or the weight of the major organs between the two groups. Haematological examination in both groups was normal apart from increased immunoglobulin E levels in mice fed a reduced magnesium and zinc diet. These mice may be useful models of atopic dermatitis; preparation of the animals is not particularly time consuming, the reproducibility is 100%, and atopic dermatitis symptoms occur even in a specific pathogen-free environment.

Quantitative Three-Dimensional Analysis of the Intracellular Trafficking of Plasmid DNA Transfected by a Nonviral Gene Delivery System Using Confocal Laser Scanning Microscopy

Since endosomal escape and the nuclear delivery of plasmid DNA (pDNA) constitute major barriers for transgene expression, a quantitative evaluation of intracellular trafficking of pDNA would be highly desirable in terms of optimizing a nonviral gene delivery system. In the present study, a novel strategy is proposed for the quantification of rhodamine-labeled pDNA in endosomes/lysosomes, cytosol, and nucleus. Endosomes/lysosomes and nucleus were stained with LysoSensor DND-189 and Hoechst 33258, respectively, to distinguish them from the cytosol. The pixel areas of the clusters derived from the rhodamine were used as an index for the amount of pDNA. This approach was applied to the analysis of the intracellular trafficking of pDNA transfected by LipofectAMINE PLUS, stearylated octaarginine (STR-R8), and octaarginine (R8). In the case of R8, most of the pDNA was trapped by endosomes/lysosomes. STR-R8 exhibited endosomal escape followed by nuclear translocation in a time-dependent manner. LipofectAMINE PLUS was the most effective in rapidly delivering pDNA to the nucleus as well as the cytosol. These differences in the intracellular trafficking of pDNA correlated well with the transgene expression. Therefore, this method enables the quantitative analysis of the intracellular pharmacokinetics of pDNA and promises to provide useful information for optimizing nonviral gene delivery systems.

Differential relationship between changes in tumour size and microcirculatory functions induced by therapy with an antivascular drug and with cytotoxic drugs. implications for the evaluation of therapeutic efficacy of AC7700 (AVE8062)

A novel combretastatin A-4 derivative, AC7700, which is now in Phase I clinical trials under a new code, AVE8062, has shown strong antitumour effects against solid tumours in rodents because of its powerful and continued stanching of the tumour blood flow (TBF). Despite the strong tumour-suppressing qualities of AC7700, it does not produce an immediate reduction in tumour size. To elucidate the reason for this effect, we investigated the relationship between the change in tumour size in Sato lung carcinoma (SLC) and circulatory functions after therapy with AC7700, doxorubicin (Adriamycin [ADR]), or mitomycin C (MMC). To measure time-lapse changes in TBF with the hydrogen clearance method at the same site after drug administration, we developed a new apparatus for keeping electrodes within a tumour. AC7700 led to the destruction of both cancer cells and tumour vessels by interrupting the supply of nutrients. Intravenous (i.v.) administration of fluorescent dyes after AC7700 treatment revealed no fluorescence within the tumour vessels, which confirmed that the tumour microcirculation had been completely blocked. In contrast, ADR led to the destruction of SLC tumour cells, but did not have the same effect on tumour vessels. Intravenously administered fluorescent dyes immediately reached the tumour, which indicated that the tumour vasculature remained intact, and the TBF remained at the preadministration level, even 6 days after ADR treatment. In addition, although the size of the tumour increased slightly for 2 days with ADR treatment, possibly because of swelling of the cancer cells, thereafter it continued to decrease. MMC had virtually no effect on SLC tumour cells, tumour size or tumour vessels. We conclude that changes in tumour size brought about by cancer chemotherapy depend not only on the sensitivity of the cancer cells to the drug in question, but also on the nature of changes in the microcirculatory functions of the tumour brought about by the therapy. When both tumour cells and the tumour vasculature are destroyed, the effectiveness of therapy can not be determined from changes in tumour size alone.

KAI1 expression can be a predictor of stage A prostate cancer progression

The disease progression and rate of cancer death were analyzed in 52 patients with stage A prostate cancer who underwent transurethral resection of the prostate (TURP) or retropubic subcapsular prostatectomy (SCP) between 1987 and 1998. We performed immunohistochemistry on 16 patients to determine the correlation between the expression of the tumor metastasis suppressor gene KAI1 and the subsequent progression of stage A prostate cancer. Nineteen and 33 of the patients had cancer at stage A1 and stage A2, respectively, and their subsequent courses were followed for an average of 53.7 months (24-134 months). Progression to clinical cancer was found in six patients (one with stage A1, and five with stage A2). This progression was evident 40.8 months (5-80 months) after TURP or SCP. Four (66.7%) of the patients died of cancer progression (average 31 months) after prostatectomy. All four patients had stage A2, poorly differentiated adenocarcinoma, and had been followed with administration of diethylstilbestrol diphosphate (DES-P). The disease-free patients (n=10) showed overexpression of KAI1 protein, compared to those with disease progression (n=6). These results indicate that progression arose mainly in the patients with stage A2 cancer, and that poorly differentiated, focal and weak expression of KAI1 protein is highly associated with disease progression. It is suggested that patients in this group should be treated with immediate total androgen blockade, radiation, or radical prostatectomy after diagnosis.Prostate Cancer and Prostatic Diseases (2001) 4, 150-153.

Identification of a short highly conserved amino acid sequence as the functional region required for posttranscriptional autoregulation of the cystathionine gamma-synthase gene in Arabidopsis

Cystathionine gamma-synthase (CGS) catalyzes the first committed step of Met biosynthesis in plants. We have previously shown that expression of the gene for CGS is feedback-regulated at the level of mRNA stability, and that the amino acid sequence encoded by the first exon of the CGS gene itself is responsible for the regulation (Chiba, Y., Ishikawa, M., Kijima, F., Tyson, R. H., Kim, J., Yamamoto, A., Nambara, E., Leustek, T., Wallsgrove, R. M., and Naito, S. (1999) Science 286, 1371-1374). To identify the functional region within CGS exon 1, deletion analysis was performed. The results showed that the 41-amino acid region of exon 1 highly conserved among plants is necessary and sufficient for the regulation. Analyses of in vivo and in vitro generated mutations that abolish the regulation identified the functionally important amino acids as 11-13 residues within this conserved region. The importance of these residues was confirmed by deletion analysis within the conserved region. These studies identified the functional region of CGS exon 1 required for the posttranscriptional autoregulation of the CGS gene as (A)RRNCSNIGVAQ(I), with uncertainty of the first and last residues. This sequence is almost perfectly conserved among CGS sequences of higher plants but cannot be found elsewhere in the public databases.