Timing of Surgery and Pathologic Complete Response (pCR) after Completing Total Neoadjuvant Therapy for Rectal Adenocarcinoma: A Retrospective Study of the National Cancer Database

PURPOSE/OBJECTIVE(S)

Total neoadjuvant therapy (TNT) is a treatment strategy for rectal cancer that includes a course of multiagent chemotherapy and a separate course of radiation +/- concurrent chemotherapy before definitive surgery. The use of TNT has increased in recent years and carries the potential for improved sphincter preservation and a significant risk reduction of locoregional recurrence. However, the influence of rest period from end of radiation to surgery after TNT is unclear. The objective of this study was to evaluate the relationship between rest period and pCR using data from the National Cancer Database. We hypothesized that longer duration of rest period before surgery will be positively associated with pCR.

MATERIALS/METHODS

Patients aged 18 years and older diagnosed with primary rectal cancer between 2016 and 2020, who underwent an NCCN-recommended TNT regimen followed by definitive surgery at a Commission on Cancer-accredited facility were retrospectively analyzed in the current study. We included 5,997 patients who met the following inclusion criteria: clinical stage T2 and above, any N stage, M0, adenocarcinoma histology, and not receiving any adjuvant therapy. Logistic regression methods were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between duration of rest period and pCR. Restricted cubic splines were used to evaluate potential non-linear relationship between duration of rest period and pCR.

RESULTS

The median age of the study sample was 57 years old (interquartile range: 49 - 65), with majority of them being males (62.3%) and reporting Non-Hispanic White race and ethnicity (75.5%). The overall pCR rate was 18.6%. The majority received long-course radiation (76.7%) and induction chemotherapy (86.3%). In multivariable adjusted models, there was a non-linear relationship between duration of rest period and pCR (p = 0.036). Rest periods of 8-24 weeks were significantly associated with elevated odds of pCR with the odds highest at 14 weeks (OR = 2.86, 95% CI: 1.20 - 6.84) when compared to rest periods of less than a week. There was no difference in pCR between long-course vs. short course radiation and no difference between those who received induction chemotherapy vs. consolidative chemotherapy. Although the rest period is inherently longer when radiation therapy precedes consolidative chemotherapy, the order of chemotherapy to radiation itself did not impact pCR but rather the duration of rest period.

CONCLUSION

These data demonstrate an ideal window for surgery to achieve pCR in rectal cancer in the TNT era and the need for further prospective investigations of optimal rest period before surgery to achieve maximal pCR with homogenous TNT treatment regimens.

Kaon Photoproduction and the Λ Decay Parameter α_{-}

The weak decay parameter α_{-} of the Λ is an important quantity for the extraction of polarization observables in various experiments. Moreover, in combination with α_{+} from Λ[over ¯] decay it provides a measure for matter-antimatter asymmetry. The weak decay parameter also affects the decay parameters of the Ξ and Ω baryons and, in general, any quantity in which the polarization of the Λ is relevant. The recently reported value by the BESIII Collaboration of 0.750(9)(4) is significantly larger than the previous PDG value of 0.642(13) that had been accepted and used for over 40 years. In this work we make an independent estimate of α_{-}, using an extensive set of polarization data measured in kaon photoproduction in the baryon resonance region and constraints set by spin algebra. The obtained value is 0.721(6)(5). The result is corroborated by multiple statistical tests as well as a modern phenomenological model, showing that our new value yields the best description of the data in question. Our analysis supports the new BESIII finding that α_{-} is significantly larger than the previous PDG value. Any experimental quantity relying on the value of α_{-} should therefore be reconsidered.

Finite-Volume Spectrum of π^{+}π^{+} and π^{+}π^{+}π^{+} Systems

The ab initio understanding of hadronic three-body systems above threshold, such as exotic resonances or the baryon spectrum, requires the mapping of the finite-volume eigenvalue spectrum, produced in lattice QCD calculations, to the infinite volume. We present the first application of such a formalism to a physical system in form of three interacting positively charged pions. The results for the ground state energies agree with the available lattice QCD results by the NPLQCD collaboration at unphysical pion masses. Extrapolations to physical pion masses are performed using input from effective field theory. The excited energy spectrum is predicted. This demonstrates the feasibility to determine three-body amplitudes above threshold from lattice QCD, including resonance properties of axial mesons, exotics, and excited baryons.

Chiral Extrapolations of the ρ(770) Meson in Nf = 2 + 1 Lattice QCD Simulations

Several lattice QCD simulations of meson-meson scattering in p-wave and Isospin = 1 in Nf = 2 + 1 flavours have been carried out recently. Unitarized Chiral Perturbation Theory is used to perform extrapolations to the physical point. In contrast to previous findings on the analyses of Nf = 2 lattice data, where most of the data seems to be in agreement, some discrepancies are detected in the Nf = 2 + 1 lattice data analyses, which could be due to different masses of the strange quark, meson decay constants, initial constraints in the simulation, or other lattice artifacts. In addition, the low-energy constants are compared to the ones from a recent analysis of Nf = 2 lattice data.

N-cadherin knockdown leads to disruption of trophoblastic and endothelial cell interaction in a 3D cell culture model - New insights in trophoblast invasion failure

INTRODUCTION

Trophoblast homing to maternal spiral arteries is mandatory for successful placentation. Cell-cell adhesion molecules regulate this process and adhesion molecule expression is altered in impaired placentation. We hypothesize that, similar to immune cell recruitment, trophoblast cell adherence and rolling are primarily mediated by adhesion molecules like, cadherins, immunoglobulins, selectins and their partnering ligands. Here, the interdependence of adhesion molecule expression in trophoblastic cell lines of diverse origin was investigated in relation to their interaction with endothelial cell networks on Matrigel® co-cultures and the effect of specific adhesion molecule knockdown analyzed.

METHODS

Trophoblastic cells were labeled in red and co-cultured with green HUVEC networks on Matrigel®. Association was quantified after collection of fluorescence microscopy pictures using Wimasis® internet platform and software. Expression of adhesion molecules was analyzed by PCR and Western blot, immuno-fluorescence and flow cytometry. The impact of adhesion molecules on trophoblast-endothelial-cell interaction was investigated using siRNA technique.

RESULTS

N-cadherin and CD162 were specifically expressed in the trophoblast cell line HTR-8/SVneo, which closely adhere to and actively migrate toward HUVEC networks on Matrigel®. Suppression of N-cadherin led to a significant alteration in trophoblast-endothelial cell interaction. Expression of VE-cadherin in closely interacting trophoblast cells was not confirmed in vitro.

DISCUSSION

We identified N-cadherin to mediate specific interaction between HUVEC and the migrating trophoblast cells HTR-8/SVneo in a Matrigel® co-culture model. VE-cadherin contribution could not be confirmed in vitro. Our results support the hypothesis that impaired N-cadherin but not VE-cadherin expression is involved in trophoblast recruitment to the maternal endothelium.

Evaluation of a palliative and hospice care telephone hotline for patients severely affected by multiple sclerosis and their caregivers

BACKGROUND AND PURPOSE

Palliative and hospice care (PHC) still mainly focuses on patients with cancer. In order to connect patients severely affected by multiple sclerosis (MS) and caregivers to PHC, a nationwide hotline was implemented to facilitate access to PHC.

METHODS

The hotline was designed in cooperation with the German Multiple Sclerosis Society. Self-disclosed information given by callers was documented using case-report forms supplemented by personal notes. Data were analysed descriptively.

RESULTS

A total of 222 calls were documented in 27 months. The patients' mean age was 51.12 years (range 27-84 years) and mean illness duration was 18 years (range 1 month to 50 years). Inquiries included information on PHC (28.8%) and access to PHC (due to previous refusal of PHC, 5.4%), general care for MS (36.1%), adequate housing (9.0%) and emotional support in crisis (4.5%). A total of 31.1% of callers reported 'typical' palliative symptoms (e.g. pain, 88.4%), 50.5% reported symptoms evolving from MS and 35.6% reported psychosocial problems. For 67 callers (30.2%), PHC services were recommended as indicated.

CONCLUSIONS

The hotline provided insight into the needs and problems of patients severely affected by MS and their caregivers, some of which may be met by PHC. Future follow-up calls will demonstrate if the hotline helped to improve access to PHC beyond providing information. Overall, the hotline seemed to be easily accessible for patients severely affected by MS whose mobility is limited.

Predictions for the [Formula: see text] decay

We calculate the shape of the [Formula: see text] and [Formula: see text] invariant mass distributions in the [Formula: see text] and [Formula: see text] decays that are dominated by the [Formula: see text] resonance. The weak interaction part is the same for both processes and the hadronization into the different meson-baryon channels in the final state is given by symmetry arguments. The most important feature is the implementation of the meson-baryon final-state interaction using two chiral unitary models from different theoretical groups. Both approaches give a good description of antikaon-nucleon scattering data, the complex energy shift in kaonic hydrogen and the line shapes of [Formula: see text] in photoproduction, based on the two-pole scenario for the [Formula: see text]. We find that this reaction reflects more the higher mass pole and we make predictions of the line shapes and relative strength of the meson-baryon distributions in the final state.

A blue luminescent MOF as a rapid turn-off/turn-on detector for H2O, O2and CH2Cl2, MeCN: 3∞[Ce(Im)3ImH]·ImH

A blue emitting MOF is presented as a fast turn-off/turn-on detector for various analytes utilising 5d–4f-transitions of Ce³⁺.

Detection of ki-ras mutation in nonneoplastic mucosa of Japanese patients with colorectal cancers

About 50% of colorectal adenocarcinoma in humans have been reported to contain mutated Ki-ras gene. To provide a better understanding for the possible role of this mutation and to examine whether its presence can reliably predict a risk of colorectal cancer, we have analyzed the normal appearing mucosa of patients with colorectal adenocarcinoma. With an Enriched PCR procedure, we can detect mutated Ki-ras allele in the presence of 10(3) to 10(4) normal alleles. Only by this procedure was Ki-ras mutation detected in the non-neoplastic colonic mucosa of 9 out of 50 (18%) Japanese patients with colorectal cancer. This analysis indicated that epithelial cells which carry mutated Ki-ras gene were 100- to 1000-fold less frequent in the non-neoplastic mucosa than at the tumor site. The presence of ras gene mutation in normal appearing mucosa points to a previous exposure which had initiated the multistage process of colorectal carcinogenesis.

Abstract P1-01-04: Axillary Intervention in Patients Undergoing Neoadjuvant Therapy (NST) — First Results from the SENTINA Study

Background: The optimal scheduling for sentinel lymph node biopsy (SLNB) among patients with breast cancer undergoing neoadjuvant systemic therapy (NST) is unclear. SENTINA-study is the first prospective multicenter trial that systematically examines the feasibilty and reliability of SLNB prior to and after (NST). Here we present results of a first exploratory analysis by examining distribution of N-stages in the different treatment arms and correlating the axillary status with the type of breast surgery (breast conserving therapy [BCT] vs mastectomy [ME]).

Methods: The SENTINA study is a four-arm multicenter (n= XXX) observation study. Patients will be stratified based on their clinical lymph node status prior to treatment. If the lymph node status is clinically negative SLNB is performed before NST. Patients with a negative SLN will undergo no further axillary surgery (Arm A), whereas patients with a positive SLN will be treated with sentinel-node-guided axillary dissection (SLNB-AD) after NST (Arm B). If the lymph node is clinically positive upon initial presentation, patients will undergo NST prior to any axillary intervention. If patients convert to a clinically negative lymph node status through NST they will undergo SLNB-AD (ARM C). Patients with persistent positive nodes or whose tumors progress under NST undergo primary axillary dissection (Arm D). Clinically node positive patients will be endcouraged to undergo FNA to confirm their lymph node status. A total of 1508 patients in the entire study will be needed to calculate the false-negative rate in this group with a one-sided 95% confidence interval not exceeding 10%.

Results: 873 patients have been accrued into SENTINA until may 31th 2010, 523 (59,9%) have completed their treatment. 180 (34,4%) women have been treated in Arm A and 117 (22,4%) in Arm B. In 170 (32,5%) patients the clinical axillary status converted from a clinical positive to a clinical negative status (Arm C). In 65 pts (12,4%) the axillary status remained positive or the tumor progressed under NCHT (Arm D). BCT rates in Arm A-D were 88.3%, 75.2%, 61.8% and 22.2% respectively.

Conclusion: First results of the SENTINA study show a strong correlation between the axillary status and the type of breast surgery in patients, who are treated with NST. Importantly, we demonstrate that the clinical assessment of the axillary status is unprecise. There is an urgent need to optimize the tailoring of axillary intervention in the setting of NST

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-04.

IDH1 and IDH2 mutation studies in 1473 patients with chronic-, fibrotic- or blast-phase essential thrombocythemia, polycythemia vera or myelofibrosis

In a multi-institutional collaborative project, 1473 patients with myeloproliferative neoplasms (MPN) were screened for isocitrate dehydrogenase 1 (IDH1)/IDH2 mutations: 594 essential thrombocythemia (ET), 421 polycythemia vera (PV), 312 primary myelofibrosis (PMF), 95 post-PV/ET MF and 51 blast-phase MPN. A total of 38 IDH mutations (18 IDH1-R132, 19 IDH2-R140 and 1 IDH2-R172) were detected: 5 (0.8%) ET, 8 (1.9%) PV, 13 (4.2%) PMF, 1 (1%) post-PV/ET MF and 11 (21.6%) blast-phase MPN (P<0.01). Mutant IDH was documented in the presence or absence of JAK2, MPL and TET2 mutations, with similar mutational frequencies. However, IDH-mutated patients were more likely to be nullizygous for JAK2 46/1 haplotype, especially in PMF (P=0.04), and less likely to display complex karyotype, in blast-phase disease (P<0.01). In chronic-phase PMF, JAK2 46/1 haplotype nullizygosity (P<0.01; hazard ratio (HR) 2.9, 95% confidence interval (CI) 1.7-5.2), but not IDH mutational status (P=0.55; HR 1.3, 95% CI 0.5-3.4), had an adverse effect on survival. This was confirmed by multivariable analysis. In contrast, in both blast-phase PMF (P=0.04) and blast-phase MPN (P=0.01), the presence of an IDH mutation predicted worse survival. The current study clarifies disease- and stage-specific IDH mutation incidence and prognostic relevance in MPN and provides additional evidence for the biological effect of distinct JAK2 haplotypes.

IDH1 and IDH2 mutation analysis in chronic- and blast-phase myeloproliferative neoplasms

Bone marrow DNA was screened for isocitrate dehydrogenase (IDH) mutations in 200 patients with chronic (n=166) or blast (n=34) phase myeloproliferative neoplasms (MPN). Included among the former were 77 patients with primary myelofibrosis (PMF), 47 essential thrombocythemia and 38 polycythemia vera (PV). Nine IDH mutations (5 IDH1 and 4 IDH2) were detected; mutational frequencies were approximately 21% (7 of 34) for blast-phase MPN and approximately 4% (3 of 77) for PMF. IDH mutations were seen in only 1 of 12 paired chronic-blast-phase samples and in none of 27 concurrently studied acute myeloid leukemia (AML) patients without antecedent MPN. IDH1 mutations included R132C (n=4; two post-PMF AML, one post-PV AML and one PMF) and R132S (n=1; post-PMF AML). IDH2 mutations included R140Q (n=3; one post-PMF AML, one post-PV AML and one PMF) and a novel R140W (n=1; mutation found in both chronic- and blast-phase samples). The entire study cohort was also screened for JAK2 and MPL mutations and JAK2V617F was found in three IDH-mutated cases (two PMF and one PV). This study shows a relatively high incidence of IDH mutations in blast-phase MPN, regardless of JAK2 mutational status, and the occurrence of similar mutations in chronic-phase PMF.

[Extremely elderly patient in whom the pacing lead was implanted via the femoral vein]

We report on an extremely elderly patient in whom we were unable to insert a pacing lead via the subclavian or internal jugular vein because of a superior vena cava obstruction; we instead inserted the pacing lead via the femoral vein. The patient was a 98-year-old male. Thirty-nine years previously, pacemaker implantation was performed for complete atrioventricular block. Afterwards, pacemaker replacement and reimplantation had been performed a total of 15 times. The patient was recently admitted because of pacing failure. Pacemaker replacement was performed, but pacing was not possible because of disconnection of the pacing lead. Insertion of a new pacing lead was attempted via both subclavian veins and the right jugular vein but failed; this approach was abandoned and temporary pacing was done. Superior vena cava obstruction was noted on chest computed tomography (CT), and pacing lead insertion through the superior vena cava was deemed unfeasible. Myocardial electrode implantation was also considered, but general anesthesia was deemed problematic because of the patient's extreme age. A pacing lead was inserted via the right femoral vein, and the generator was implanted in the right lower abdomen. Postoperative pacing was satisfactory.

Antibody against vascular endothelial growth factor (VEGF) inhibits angiogenic switch and liver metastasis in orthotopic xenograft model with site-dependent expression of VEGF

We previously reported that upregulation of angiogenesis, i.e. angiogenic switch (AS), may occur simultaneously to initiation of invasion in the early development of human colon cancer. We also showed that mRNA upregulation of the gene of vascular endothelial growth factor (VEGF) occurs immediately prior to metastasis in human colon cancer in an orthotopic nude mouse model of colon cancer liver metastasis. In this paper, we studied whether the antibody against VEGF inhibits AS and liver metastasis in an orthotopic xenograft model with site-dependent expression of VEGF. We examined levels of vessel density, VEGF mRNA by in situ hybridization (ISH) method and liver metastasis in pre-AS (on days 8 and 11) and post-AS (on days 15 and 18) treatment groups. The mean vessel density and the intensity of VEGF mRNA by ISH in the pre-AS treatment group were significantly lower than those for the post-AS treatment and the control group. Liver metastases were completely inhibited (0/10) in the pre-AS treatment, while they occurred in 4 out of 10 and 5 out of 10 mice in the post-AS treatment and the control groups, respectively (p<0.01). These results suggest that VEGF antibody treatment performed before AS could efficiently inhibit AS and liver metastasis, which may indicate that VEGF antibody has another potential as a drug for chemoprevention of colon cancer.

Use of multiple displacement amplification to amplify genomic DNA before sequencing of the alpha and beta haemoglobin genes

AIMS

To evaluate the technique of multiple displacement amplification (MDA) for whole genome amplification from small volume blood samples before sequencing in a clinical test to identify haemoglobin gene mutations.

METHODS

Phage phi29 DNA polymerase was used to perform MDA, starting with either 1 micro l of blood or 1 ng of previously isolated blood DNA from 23 patients. The amplified products were then evaluated using a clinical test that involves sequencing the haemoglobin genes to detect mutations. The results were compared with the current clinical test method that uses genomic DNA isolated using column based technology.

RESULTS

The MDA technique produced large quantities (theoretically approximately 2 mg) of DNA. The amplification procedure was extremely easy and took about four hours (less than one hour of hands on technician time and three hours for amplification). When MDA products were used in the same clinical test protocol as genomic DNA isolated using column technology, there was 100% concordance for detection of a variety of point mutations in the alpha1, alpha2, and beta globin genes.

CONCLUSIONS

The MDA technique is useful for overcoming the problem of insufficient genomic DNA in clinical specimens requiring haemoglobin gene sequencing and could be useful for other clinical applications.

Endosonographic evaluation of c-kit-positive gastrointestinal stromal tumor

BACKGROUND

Endosonographic features of c-kit-positive gastrointestinal stromal tumors (GISTs) were compared with those of leiomyomas and schwannomas.

METHODS

Twenty-four patients with gastric mesenchymal tumors who underwent endoscopic ultrasonography (EUS) and surgical treatment were enrolled. GISTs were defined as c-kit (CD117)-positive tumors, leiomyomas as desmin-positive and c-kit-negative tumors, and schwannomas as S-100-positive and c-kit-negative tumors. Invasion to adjacent organs or more than 20 mitotic counts per 50 high power fields indicated malignancy.

RESULTS

There were 19 GISTs, three leiomyomas, and two schwannomas. All five malignant tumors were GISTs. A marginal halo was found in 12 of 19 GISTs and in both of the schwannomas, but not in any of the three leiomyomas. The echogenicities of GISTs were low but higher than that of the normal proper muscle layer, whereas those of leiomyomas and schwannomas were usually low. Lobulation of the tumor surface was documented only in GISTs, particularly in malignant ones. The tumor doubling time of a malignant GIST was 9.3 months, and that of six benign GISTs was 18.7 months (range = 10.7-28.0 months).

CONCLUSION

Marginal halo and relatively higher echogenicity on EUS might suggest GIST. Marginal lobulation and a short doubling time may be signs of a malignant GIST.

Visualizing the gastric wall with a 30-MHz ultrasonic miniprobe: ex vivo imaging of normal gastric sites and sites of early gastric cancer

BACKGROUND

This study was performed to determine the echo layer structures of the normal gastric wall and early gastric cancer when visualized with a 30-MHz ultrasonic miniprobe.

METHODS

Twelve surgically resected gastric specimens were used for an ex vivo study. Eighteen normal sites and 12 early gastric cancer sites were scanned with an Olympus (XUM-S30-25R) probe with a frequency of 30-MHz. Endoscopic ultrasound images were compared with corresponding histopathologic sections stained with hematoxylin and eosin.

RESULTS

The normal mucosa was visualized as at least four alternating echo layers; the muscularis mucosa was delineated at all normal sites. Lymphoid aggregates within the mucosa could be seen. The submucosa was clearly visualized in most cases, but the muscularis propria and subserosa were seldom depicted due to attenuation of ultrasound waves. At the sites of gastric cancer, the layered architecture of the mucosa was disturbed by an irregular hypoechoic lesion. Minimal submucosal infiltration (400 and 750 micrometer) was clearly depicted in two cases, without ulceration at or around the tumor site. However, attenuation at the site of a deep ulcer scar prevented adequate visualization of the tumor extent in two other cases with ulceration.

CONCLUSION

A 30-MHz ultrasonic miniprobe may provide additional imaging information of the gastric wall and could play a role in the assessment of early cancer lesions.

The effect of the herbal medicine dai-kenchu-to on post-operative ileus

Post-operative ileus (PI) is an inevitable adverse consequence of abdominal surgical procedures. We performed a randomized study of the effects of the herbal medicine dai-kenchu-to (DKT) on 24 patients with PI. Patients received either 15 g of oral DKT or placebo daily for 14 days. The effects on upper gastrointestinal motility, frequency of secondary operation and recurrence of PI were investigated. The frequency of surgical operation was significantly lower in patients receiving DKT compared with placebo. Oral administration of DKT was clinically effective for PI in reducing both the need for further surgery and the recurrence of PI.

Myxedema accompanied by huge portal-systemic shunt without portal hypertension

A 43-year-old woman with a huge portal-systemic shunt accompanied by myxedema showed slow speech and behavior. Several imaging studies revealed a bold portal-systemic shunt from the splenic vein to the left renal vein. In addition, hypothyroidism caused by chronic thyroiditis was diagnosed, and synthesized thyroxine replacement was effective for the symptoms. However, the serum ammonia and indocyanin green retention remained in the abnormal range, nevertheless the portal vein pressure was normal and findings of liver cirrohsis were not recognized histologically. Surgical shunt closure was performed, resulting in normalized serum ammonia levels and serum branched chain amino acids /aromatic amino acids ratio, and improvement of the ammonia tolerance test.

Genomic structure, chromosome mapping and expression analysis of the human AXIN2 gene

Conductin is a Wnt signalling protein and serves as a negative regulator of beta-catenin stability. We have previously isolated the human homolog (AXIN2) of the murine conductin gene and shown that it is mutated in colorectal cancer (CRC) with defective mismatch repair (MMR). Here we report the detailed genomic structure of this gene by analysis of cDNA and genomic clones. The gene spans > or =25 kb containing ten exons ranging from 96 bp to 904 bp. All splice donor and acceptor sites conform to the GT/AG rule. FISH (Fluorescence in situ Hybridization) analysis localized this gene to human chromosome band 17q24 and showed that it exists as a single copy in the human genome. Northern blot analysis from different human organs demonstrated that the AXIN2 gene is highly expressed in human thymus, prostate, testis, small intestine and ovarian tissues but expressed at a lower level in colon. The data reported here provides a framework for further analysis of this important Wnt signalling protein in vertebrate development and tumorigenesis.

Streptococcal preparation OK-432 enhances the antitumor activity of CPT-11 by increasing Th1-cytokine production in mice

BACKGROUND

The streptococcal preparation OK-432 is an immunomodulator widely used for cancer therapy in Japan. The purpose of this study was to evaluate the efficacy of the combined treatment of OK-432 and CPT-11.

MATERIALS AND METHODS

In C57BL/6 mice inoculated with B16 melanoma, the antitumor mechanism of this combined therapy was investigated through an analysis of cytokine production by the splenocytes.

RESULTS

SN-38, the active metabolite of CPT-11, exerted dose-dependent inhibition of interferon (IFN)-gamma production induced by OK-432 in mouse splenocytes. In contrast, the optimum concentration of SN-38 increased interleukin (IL)-6 and IL-12 production by OK-432-activated splenocytes. In tumor-bearing mice, CPT-11 inhibited tumor growth and OK-432 had an additive antitumor effect with CPT-11. Investigation of cytokine production showed that CPT-11 treatment principally inhibited IL-12 and IFN-gamma production, which was improved by the combined administration with OK-432.

CONCLUSION

These results indicate that CPT-11 inhibits type-1 T helper (Th1) cells despite its potential to stimulate macrophages and that OK-432 enhances the antitumor activity of CPT-11 by increasing Th1-cytokine production.

[Significance of angiogenesis and clinical application of anti-angiogenesis]

Angiogenesis is essential for tumor growth and metastasis and depends upon the production of angiogenic factors by host and/or tumor cells. Increased vascularity may allow not only an increase in tumor growth but also a greater chance for hematogenous metastasis. We have already reported that vessel density and vascular endothelial growth factor (VEGF) expression are higher in metastatic tumors than in nonmetastatic tumors and that VEGF and its receptor, the KDR ligand/receptor system, also correlate with metastasis. Therefore the anti-VEGF antibody and VEGF receptor antagonist are potential targets for antiangiogenesis therapy in colon cancer. Clinical trials of such agents are continuing to phase II/III in the USA and Europe. In this paper, we introduce data on antiangiogenesis agents in the treatment of metastatic colorectal cancer and point out that the strategy for antiangiogenesis is not tumor shrinkage but tumor dormancy.

[Chemotherapy by combination of low-dose CPT-11 and PSK in an elderly man with liver metastasis from gastric cancer]

We attempted a new regimen of low-dose CPT-11 and PSK against a high age man with liver metastasis from gastric cancer. CPT-11 was administered at 20 mg/m2/day x 2/week, and PSK was given orally 3.0 g/day daily, respectively. Serum CEA level decreased gradually and almost reached normal limits (130 to 3.0 ng/ml). The tumor was reduced more than 50% at 13 weeks after the start of chemotherapy, when it had been continued for more than 8 weeks. There were no adverse effects and this regimen has been continued for more than 20 weeks without missing a week. These results suggest that the combination of low-dose CPT-11 and PSK has fewer side effects even in an elderly patient and may induce not only tumor shrinkage but also a prolonged time to progression.

Monocyte chemoattractant protein-1 and macrophage infiltration in hypertensive kidney injury

BACKGROUND

We investigated whether monocyte chemoattractant protein-1 (MCP-1) is expressed in hypertensive nephrosclerosis, and tested the effect of angiotensin II type 1 receptor blockade on MCP-1 expression and macrophage (MPhi) infiltration.

METHODS

Rats with two-kidney, one-clip (2K1C) hypertension with and without treatment with the angiotensin II type 1 receptor antagonist valsartan (3 mg/kg/day) were studied. In these animals as well as in spontaneously hypertensive rats (SHR), stroke-prone SHR (SHR-SP), hypertensive mRen-2 transgenic rats (TGR), and respective control strains, MCP-1 expression in the kidney was investigated by Northern and Western blots and by immunohistochemistry. Glomerular and interstitial MPhis were counted.

RESULTS

In the nonclipped kidney of 2K1C rats, MCP-1 expression was elevated at 14 and 28 days when significant MPhi infiltration was present. MCP-1 was localized to glomerular endothelial and epithelial cells, interstitial and tubular cells, MPhis, and vascular smooth muscle cells. A similar pattern of MCP-1 staining was present in TGR kidneys, whereas MCP-1 expression was not increased in SHR and SHR-SP. Valsartan reduced but did not normalize blood pressure, blocked the induction of MCP-1 protein in 2K1C kidneys, and decreased interstitial MPhi infiltration significantly.

CONCLUSION

MCP-1 expression is increased in angiotensin II-dependent models of hypertensive nephrosclerosis and is temporally and spatially related to MPhi infiltration. The angiotensin II type 1 receptor mediates the induction of MCP-1.

Altered expression of beta-catenin and c-erbB-2 in early gastric cancer

To investigate the possible relationship between altered expression (loss of membranous staining or nuclear accumulation) of beta-catenin and invasion/metastasis in early gastric cancer (EGC), beta-catenin was detected immunohistochemically in 116 cases of EGC, including 86 differentiated and 30 undifferentiated carcinomas. In parallel, immunohistochemical expression of c-erbB-2 was analyzed in all EGC cases. Regardless of histological type, altered expression of beta-catenin was found in 47% of mucosal carcinomas and 89% of carcinomas with submucosal invasion (p<0.001). Of particular interest is that beta-catenin alteration was found in almost all EGCs with lymph node metastasis, even though no significant statistical comparison could be made. These results suggest that molecular changes resulting in abnormal beta-catenin expression participate in the process of submucosal invasion and metastasis. While loss of expression was preferentially observed in undifferentiated EGCs, nuclear accumulation was found exclusively in 24% of differentiated EGCs. c-erbB-2 was overexpressed in only 16% of differentiated EGCs but there was no correlation between this overexpression and invasion or metastasis. However, it is intriguing that 12 out of 14 cases with c-erbB-2 overexpression also showed altered beta-catenin expression, suggesting that both molecules are involved in the development of a certain set of differentiated EGCs.

[Weekly chemotherapy with alternating low-dose CPT-11 and low-dose FP against a far advanced pancreatic cancer--a case report]

We attempted a new regimen of weekly chemotherapy with alternating low-dose CPT-11 and low-dose FP against a case of far advanced pancreatic cancer with invasion to the super mesentric artery, celiac artery, and left renal vein. CPT-11 was administered at 25 mg/m2/day x 3/week, and CDDP and 5-FU were administered at 7 mg and 350 mg/m2/day x 3/week by intravenous infusion. These regimens were alternated every week. The serum CA19-9 level decreased gradually with a half time of approximately 2 months (from 972 to 126 U/ml). The tumor was reduced more than 50% 4 months after chemotherapy, and continuing decreasing for more than 6 months. There were no adverse effects except mild leukopenia (less than Grade 1). These results suggest that the combination of low-dose chemotherapy with fewer side effects may be effective not only for tumor shrinkage, but also for a prolonged time to progression.

Prolonged stable disease effects survival in patients with solid gastric tumor: analysis of phase II studies of doxifluridine

We have previously reported that the survival time of most patients with solid tumors depend primarily on the length of the cytostatic phase rather than the extent of reduction induced. We analyzed a phase II study of doxifluridine, an intermediate metabolite of capecitabine, in gastric cancer to confirm our concept, because doxifluridine has shown low response rates (14%; 20/140) and long median survival times (371 days). The time to progression curves between the responder and stable disease were almost the same. The survival curves of the patients with stable disease of more than 90 days to progression (32 pts.) and responders were not significantly different.

K-ras mutation: early detection in molecular diagnosis and risk assessment of colorectal, pancreas, and lung cancers--a review

Multiple genomic alterations are involved in the development of most human cancers. They include alterations in oncogenes, tumor suppressor genes, DNA mismatch repair and excision repair genes. Genetic testing for susceptibility has been a part of the management of patients with well-defined but uncommon hereditary cancers in which certain susceptible gene mutations are determined in the germ line. However, a molecular diagnostic approach to sporadic cancers, which comprise the vast majority of malignant tumors in human beings, is still under development. One of the best characterized tumor-related genes is K-ras, which somatically mutates in several types of sporadic human cancers. Since mutations of this gene occur exclusively in three hot spots (codons 12, 13 and 61), and are frequently detected and well characterized in colorectal, pancreas and lung cancers, molecular diagnosis and susceptibility (risk) assessment targeting K-ras mutations are being developed. For this purpose, sample collection methods that reflect the state of the entire affected organ are important. Clinical samples used for molecular diagnosis and risk assessment include stool and lavage fluid, pancreatic and duodenal juices, and sputum and lavage fluids for colorectal, pancreas and lung cancers, respectively. The reported incidence of K-ras mutations detected in these samples ranges from 7% to 80% for colorectal cancers, 25% to 87% for pancreatic cancers, and 25% to 48% for lung cancers. Incidence of mutations clearly depends on the sensitivity of the method for detecting the mutant K-ras allele, as well as the nature and the quality of the clinical samples. Various methods including plaque hybridization, dot blot hybridization, combined PCR and RFLP or SSCP, and sensitive PCR have been used, and they exhibited high specificity (75 to 100%) in detecting mutations. Molecular analysis is demonstrating promise in assessing susceptibility to, or risk of developing, sporadic cancers.

[Significance of prolonged NC as an endpoint of chemotherapy for solid tumors]

The goals of chemotherapy in patients with cancer should be both tumor shrinkage and extension of survival time. Believing that there is a clear correlation between the extent of treatment-induced tumor reduction and survival time, we have made an effort to reduce tumor size. However, many investigators have found no positive correlation between response rate and median survival time in various cancers, including non-small cell lung cancer and gastric cancer. If this is the case, we should reconsider our therapeutic strategy. We previously reported that doctors should induce a prolonged dormant phase rather than strive to shrink tumor mass in "Tumor Dormancy Therapy," because the survival of most patients with solid tumors depends on the length of the induced dormant phase rather than on induced tumor reduction. In this paper, we analyzed two Japanese phase II studies of gastric cancer. There were no significant differences between the survival of NC patients with TTP of more than 90 days and CR + PR patients in either study. These results suggest prolonged NC could contribute to longer survival, and we concluded that NC patients with greater than 90 days of TTP, that is "prolonged NC," exhibited similar survival relative to those with effective treatments and tumor shrinkage, and should be evaluated as a positive response.

Analysis of JNK, Mdm2 and p14(ARF) contribution to the regulation of mutant p53 stability

Identification of Mdm2 and JNK as proteins that target degradation of wt p53 prompted us to examine their effect on mutant p53, which exhibits a prolonged half-life. Of five mutant p53 forms studied for association with the targeting molecules, two no longer bound to Mdm2 and JNK. Three mutant forms, which exhibit high expression levels, showed lower affinity for association with Mdm2 and JNK in concordance with greater affinity to p14(ARF), which is among the stabilizing p53 molecules. Monitoring mutant p53 stability in vitro confirmed that, while certain forms of mutant p53 are no longer affected by either JNK or Mdm2, others are targeted for degradation by JNK/Mdm2, albeit at lower efficiency when compared with wt p53. Expression of wt p53 in tumor cells revealed a short half-life, suggesting that the targeting molecules are functional. Forced expression of mutant p53 in p53 null cells confirmed pattern of association with JNK/Mdm2 and prolonged half-life, as found in the tumor cells. Over-expression of Mdm2 in either tumor (which do express endogenous functional Mdm2) or in p53 null cells decreased the stability of mutant p53 suggesting that, despite its expression, Mdm2/JNK are insufficient (amount/affinity) for targeting mutant p53 degradation. Based on both in vitro and in vivo analyses, we conclude that the prolonged half-life of mutant p53 depends on the nature of the mutation, which either alters association with targeting molecules, ratio between p53 and targeting/stabilizing molecules or targeting efficiency.