Recent progress in gene therapy for Parkinson's disease

Parkinson's disease (PD) is an age-related and the second most common neurodegenerative disorder beyond Alzheimer's disease. A neuropathological hallmark of PD is a prominent loss of dopaminergic neurons in the substantia nigra projecting into the caudate and putamen. Oral administration of L-dopa and/or dopamine agonists ameliorates cardinal motor symptoms of PD. However, an intermittent and long-term treatment with L-dopa frequently induces adverse side effects such as motor fluctuations and dyskinesia. As alternative therapeutic strategies, the following four approaches are currently under evaluation for clinical gene therapy trials in PD; 1) recombinant adeno-associated virus 2 system encoding aromatic L-amino acid decarboxylase (AADC), 2) glutamic acid decarboxylase (GAD) and 3) Neurturin, and 4) equine infectious anemia virus-based lentiviral system encoding AADC, tyrosine hydroxylase (TH) and GTP cyclohydrolase I (GCH) in a single transcriptional unit. GAD and Neurturin have been assessed in double blind placebocontrolled phase II studies; GAD showed a significant improvement in motor function, and Neurturin, although it failed to show significant effects at 12 months post-treatment, exhibited promising outcomes in additional examinations at 18 months. The other two approaches also represented significant effects in phase I or I/II studies. Adverse side effects due to surgery have not been observed. Here, we review preclinical and clinical trials encouraging further investigations of curative treatment for the patients suffering from PD.

Noninferiority of S-1 to UFT/LV as adjuvant chemotherapy for stage III colon cancer: A randomized phase III trial (ACTS-CC)

3518

Background: The ACTS-CC trial is a phase III trial designed to validate non-inferiority of S-1 to UFT/LV, a standard treatment in Japan as adjuvant chemotherapy for stage III colon cancer. This is the first report which evaluated the efficacy of S-1 as adjuvant therapy for colon cancer. Methods: 20-80 aged patients with stage III colon cancer who underwent curative surgery were randomly assigned to receive S-1 (80, 100, or 120 mg/day according to BSA on days 1 to 28, followed by 14 days rest, 4 courses) or UFT/LV (UFT: 300 to 600 mg/day according to BSA and, LV: 75 mg/day on days 1 to 28, followed by 7 days rest, 5 courses). Primary endpoint was DFS. Sample size was 1,480 determined with one-sided alpha of 0.05, power of 0.80, and non-inferiority margin of hazard ratio (HR) of 1.29. Results: Among 1535 enrolled patients between Apr. 2009 and Jun. 2010, 1518 patients (758 in S-1 group, 760 in UFT/LV group) were included in the efficacy analysis. Median follow-up was 41.3 months, the mean age at enrollment was 64.5 years, wide lymph node dissection (D3) was done in 79.8%, the median number of dissected lymph nodes was 17, and stage IIIA/IIIB/IIIC were 15%/71%/14%. The 3-year DFS rate was 75.5% in S-1 group and 72.5% in UFT/LV group. The HR of DFS was 0.85 (95%CI: 0.70-1.03) and non-inferiority of S-1 was demonstrated (p<0.0001). The completion rate of the protocol treatment was 76.5% in S-1 group and 72.5% in UFT/LV group. The overall incidence of grade ≥3 adverse events (AEs) in S-1 group and UFT/LV group were 16.0% and 14.4%: 4.4% and 5.5% for diarrhea, 4.9% and 3.5% for anorexia, 0.7% and 0.4% for leucopenia, 0.9% and 0.1% for anemia, 0.1% and 0.4% for thrombocytopenia, 1.2% and 1.5% for hyperbilirubinemia, 0.8% and 2.1% for AST elevation, and 1.1% and 3.3% for ALT elevation, respectively. Conclusions: Adjuvant therapy of S-1 for stage III colon cancer was demonstrated to be non-inferior in DFS to that of UFT/LV. Although AE profiles differed between S-1 group and UFT/LV group in this trial, incidence and degree of AEs were acceptable, and the completion rate of the protocol treatment was high. Adjuvant chemotherapy using S-1 will be a treatment option for stage III colon cancer. Clinical trial information: NCT00660894.

The rs6983267 SNP is associated with MYC transcription efficiency, which promotes progression and worsens prognosis of colorectal cancer

BACKGROUND

The oncogenic single nucleotide polymorphism rs6983267, located on 8q24.21, may affect copy number aberrations and/or expression profiles in colorectal cancer (CRC). We investigated the role of this single nucleotide polymorphism in the clinical outcome of CRC.

METHODS

Array comparative genomic hybridization (aCGH) and oligomicroarrays were performed on cancer cells from 157 primary CRC tissues. Expression profiles were analyzed by means of extraction expression module (EEM) analyses. Mutations in TP53, KRAS, and BRAF and microsatellite instability were also examined in 107 of the 157 cases.

RESULTS

aCGH analysis revealed two clusters; more frequent genomic copy number alteration (CNA) was observed in the 89 cases in cluster B than in the 18 cases in cluster A. The average CNA was higher in samples containing the major allele (GT/TT) of rs6983267 than in those containing the minor allele (GG). Additionally, MYC expression was the highest in samples containing the GG allele (n = 18), followed by the GT and TT alleles (n = 41 and 48, respectively). EEM analysis revealed dominant up-regulation of MYC in samples containing the minor allele. Moreover, the presence of the minor allele in a MYC-positive, CNA-negative context predicted a poorer prognosis than the presence of the major allele in a MYC-negative, CNA-positive context in CRC.

CONCLUSIONS

The presence of the minor allele of rs6983267 at 8q24.21 worsened the prognosis of CRC through up-regulation of MYC transcription. Furthermore, progression of CRC may require global CNA in the presence of the major allele and with lack of MYC transcription.

Evaluation of the seventh edition of the tumour, node, metastasis (TNM) classification for colon cancer in two nationwide registries of the United States and Japan

AIM

The new TNM classification is currently being implemented. We evaluated the TNM-7 staging system based on the two nationwide colon cancer registries in the United States and Japan to clarify whether this system better stratifies patients' prognoses than the TNM-6 did and to determine whether stratification can be effectively simplified.

METHODS

The Surveillance, Epidemiology, and End Results population-based data from 1988 to 2001 for 50139 colon cancer patients and the multi-institutional registry data from the Japanese Society for Cancer of the Colon and Rectum from 1984 to 1994 for 10754 patients were analysed. We devised a modified version of the TNM-7 staging system to allow simpler classification of the TN categories and compared the TNM-6, TNM-7, modified TNM-7, and the Dukes staging system based on survival curves and objective statistical tests such as likelihood ratio χ(2) tests, Akaike's information criterion, and Harrell's c-index.

RESULTS

The TNM-7 was superior to the TNM-6 in all objective statistical tests in the United States (c-index; 0.700 vs 0.696, P<0.001) as well as in the Japan data sets (0.732 vs 0.729, P=0.035). The modified TNM-7 is much simpler, but it nevertheless showed similar values to those of the original TNM-7 (c-index; the United States 0.702, Japan 0.733).

CONCLUSIONS

  The new TNM-7 is complicated but better at stratifying patients than the TNM-6 in the United States and Japan, and could be effectively simplified.

Study protocol of the SACURA trial: a randomized phase III trial of efficacy and safety of UFT as adjuvant chemotherapy for stage II colon cancer

BACKGROUND

Adjuvant chemotherapy for stage III colon cancer is internationally accepted as standard treatment with established efficacy, but the usefulness of adjuvant chemotherapy for stage II colon cancer remains controversial. The major Western guidelines recommend adjuvant chemotherapy for "high-risk stage II" cancer, but this is not clearly defined and the efficacy has not been confirmed.

METHODS/DESIGN

SACURA trial is a multicenter randomized phase III study which aims to evaluate the superiority of 1-year adjuvant treatment with UFT to observation without any adjuvant treatment after surgery for stage II colon cancer in a large population, and to identify "high-risk factors of recurrence/death" in stage II colon cancer and predictors of efficacy and adverse events of the chemotherapy. Patients aged between 20 and 80 years with curatively resected stage II colon cancer are randomly assigned to a observation group or UFT adjuvant therapy group (UFT at 500-600 mg/day as tegafur in 2 divided doses after meals for 5 days, followed by 2-day rest. This 1-week treatment cycle is repeated for 1 year). The patients are followed up for 5 years until recurrence or death. Treatment delivery and adverse events are entered into a web-based case report form system every 3 months. The target sample size is 2,000 patients. The primary endpoint is disease-free survival, and the secondary endpoints are overall survival, recurrence-free survival, and incidence and severity of adverse events. In an additional translational study, the mRNA expression of 5-FU-related enzymes, microsatellite instability and chromosomal instability, and histopathological factors including tumor budding are assessed to evaluate correlation with recurrences, survivals and adverse events.

DISCUSSION

A total of 2,024 patients were enrolled from October 2006 to July 2010. The results of this study will provide important information that help to improve the therapeutic strategy for stage II colon cancer.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00392899.

Genomic copy number of a carcinogenic single nucleotide polymorphism at 8q24 in non-risk allele colorectal cancer associated with insulin growth factor 2 receptor expression

BACKGROUND AND AIM

The incidence of both diabetes mellitus and hyperlipidemia is increasing and they are risk factors for colorectal cancer (CRC). On the other hand, the carcinogenic significance of the single nucleotide polymorphism (SNP), rs6983267 at 8q24, in CRC has been reported. The association between the SNP genotype and genes associated with diabetes or hyperlipidemia was investigated in cases of CRC.

METHODS

In 107 cases of CRC diagnosed in eight institutes from 2003 to 2008, array-CGH and cDNA microarray was performed and the data analyzed from two groups subdivided according to SNP genotype.

RESULTS

In the array-CGH data, we selected 38 genes related to diabetes or fat metabolism, and of these 10 had a correlation coefficient between the genome copy number at 8q24 locus and that of each gene. Of the 10 genes, insulin growth factor 2 receptor (IGF2R) was the only one with an expression level significantly associated with the 8q24 genotype. IGF2R expression was significantly lower in non-risk allele than in risk allele cases (P = 0.012). There was neither a diabetes- nor a fat metabolism-related gene that was significantly associated with CRC cases with the risk allele at 8q24.

CONCLUSIONS

SNP at 8q24 makes diabetes a risk factor of CRC via IGF2R, especially in genetically non-risk allele cases. We speculate that the risk allele of 8q24 might be risky enough that diabetes is not necessary to worsen the risk for CRC.

Safety of UFT/LV and S-1 as adjuvant therapy for stage III colon cancer in phase III trial: ACTS-CC trial

BACKGROUND

The Adjuvant Chemotherapy Trial of TS-1 for Colon Cancer (ACTS-CC) is a phase III trial designed to validate the non-inferiority of S-1 to UFT/leucovorin (LV) as postoperative adjuvant chemotherapy for stage III colon cancer. We report the results of a planned safety analysis.

METHODS

Patients aged 20-80 years with curatively resected stage III colon cancer were randomly assigned to receive UFT/LV (UFT, 300 mg m(-2) per day as tegafur; LV, 75 mg per day on days 1-28, every 35 days, 5 courses) or S-1 (80, 100, or 120 mg per day on days 1-28, every 42 days, 4 courses). Treatment status and safety were evaluated.

RESULTS

Of 1535 enrolled patients, a total of 1504 (756 allocated to S-1 and 748 to UFT/LV) were analysed. The completion rate of protocol treatment was 77% in the S-1 group and 73% in the UFT/LV group. The overall incidence of adverse events (AEs) were 80% in S-1 and 74% in UFT/LV. Stomatitis, anorexia, hyperpigmentation, and haematological toxicities were common in S-1, whereas increased alanine aminotransferase and aspartate aminotransferase were common in UFT/LV. The incidences of grade 3 AEs were 16% and 14%, respectively.

CONCLUSION

Although AE profiles differed between the groups, feasibility of the protocol treatment was good. Both S-1 and UFT/LV could be safely used as adjuvant chemotherapy.

X-Chromosome Inactivation Pattern Analysis for the Assessment of Cell Clonality in Cats

X-chromosome inactivation pattern (XCIP) analysis has been widely used to assess cell clonality in various types of neoplasms in humans. In the present study, a polymerase chain reaction–based feline XCIP analysis using the feline androgen receptor gene was developed. To construct the system of the analysis, polymorphism in CAG tandem repeats within the feline androgen receptor gene was explored using somatic DNAs from 50 male and 103 female cats. CAG tandem repeats in exon 1 of the feline androgen receptor gene were found to be polymorphic, containing 15 to 22 CAG repeats. Of the 103 female cats, 70 (68%) were heterozygous for the number of CAG repeats, indicating the possible usefulness of XCIP analysis in cats. Application of the feline XCIP analysis to 3 feline mammary gland adenocarcinoma cell lines revealed distinctly skewed XCIPs in these cell lines, indicating their clonal origins. Twelve (80%) of the 15 primary tissue/cell samples obtained from cats with various neoplastic diseases showed skewed XCIPs. Moreover, bone marrow samples from 3 cats with myelodysplastic syndrome were also found to have skewed XCIPs. The polymerase chain reaction–based XCIP analysis developed in this study can provide information on cell clonality in female cats, potentially facilitating the differential diagnosis of various disorders in cats.

Increased risk for CRC in diabetic patients with the nonrisk allele of SNPs at 8q24

BACKGROUND

Colorectal cancer (CRC) oncogenesis was considered to be determined by interactions between genetic and environmental factors. Specific interacting factors that influence CRC morbidity have yet to be fully investigated.

METHODS

A multi-institutional collaborative study with 1511 CRC patients and 2098 control subjects was used to compare the odds ratios for the occurrence of polymorphisms at 11 known single nucleotide polymorphisms (SNPs). TaqMan PCR and questionnaires were used to evaluate the effects of environmental exposures.

RESULTS

Variants of rs6983267 on 8q24 were the most significant markers of risk for CRC (odds ratio 1.16, 95% confidence interval 1.06-1.27, P = 0.0015). Non-insulin-dependent diabetes mellitus (DM), a higher body mass index at age 20, and meat consumption were environmental risk factors, whereas a tuna-rich diet and vitamin intake were protective factors. The cohort of rs6983267 SNP major (T) allele at 8q24 and DM had a 1.66-fold higher risk ratio than the cohort of major allele patients without DM.

CONCLUSIONS

We confirmed that interactions between the genetic background and environmental factors are associated with increased risk for CRC. There is a robust risk of the minor G allele at the 8q24 rs6983267 SNP; however, a major T allele SNP could more clearly reveal a correlation with CRC specifically when DM is present.

Optimal colorectal cancer staging criteria in TNM classification

PURPOSE

Histologic components of the TNM classification system have been repeatedly revised since the fifth edition (TNM5). TNM classification revisions provide different criteria for categorizing tumor nodules without residual lymph node structure (ND). However, there are few systematic evaluations regarding the effectiveness of these revisions.

PATIENTS AND METHODS

A multicenter pathologic review for ND in colorectal cancer (CRC) was performed. Tumor staging defined by TNM5, sixth edition (TNM6), and seventh edition (TNM7) were compared on the basis of Akaike information criterion (AIC) and Harrell's concordance index (c-index). Moreover, TNM7's prognostic value was compared between the original ND and modified criteria, which considered all regional NDs as lymph node metastasis (LNM) irrespective of the original structure.

RESULTS

In 1,716 treated patients with CRC (1994 to 1998), tumor stages (I/II/III) exhibited better prognoses in TNM7 (AIC, 3055.1; c-index, 0.7215) than in TNM6 (AIC, 3063.7; c-index, 0.7149), but not better than in TNM5 (AIC, 3051.6; c-index, 0.7240). Comparing the original TNM7 and modified criteria, 4.2% of patients were classified in different N stages (N0/N1/N2a/N2b); both AIC and the c-index were superior in the modified criteria (AIC, 3029.40; c-index, 0.7271) compared with the original criteria (AIC, 3040.58; c-index, 0.7230). Modified criteria were also associated with improved prognostic power of tumor stages (I/IIA/IIB/IIC/IIIA/IIIB/IIIC). These results were similar in another cohort of 2,242 treated patients with CRC (1999 to 2003).

CONCLUSION

The prognostic value of TNM7 is better than that of TNM6; however, improvement over TNM5 is insignificant. By considering all regional NDs as LNM irrespective of their morphology, TNM classification can be simplified and its prognostic value improved.

Down-regulation of miR-125a-3p in human gastric cancer and its clinicopathological significance

Recent reports have demonstrated that another strand of mature microRNA (miRNA), called microRNA* or 3p (5p) strand, which is generated from the same precursor miRNA (Pre-miR), has a crucial role in cellular function. We previously reported the tumor suppressive effect of miR-125a-5p in gastric cancer. The current study was designed to examine the function and clinical significance of miR-125a-3p, a partner strand of miR-125a-5p, in human gastric cancer. Quantitative RT-PCR was used to evaluate miR-125a-3p expression in 70 gastric cancer cases to determine the clinicopathologic significance of miR-125a-3p expression. In addition, the effect of miR-125a-3p on the proliferation of gastric cancer cells was investigated. Low expression levels of miR-125a-3p were associated with indicators of enhanced malignant potential such as tumor size (p=0.0002), tumor invasion (p=0.0149), lymph node metastasis (p=0.018), liver metastasis (p=0.016), peritoneal dissemination (p=0.03), advanced clinical stage (p=0.0037) and poor prognosis (p=0.0083). Multivariate analysis indicated that low miR-125a-3p expression was an independent prognostic factor for survival, while in vitro assays demonstrated that miR‑125a-3p suppressed the proliferation of gastric cancer cells. MiR-125a-3p is a potent prognostic marker in gastric cancer. The clinical significance and tumor suppressive effect of miR‑125a-3p, as well as previously reported miR-125a-5p, suggest that the functional role of another strand of the mature form miRNA cannot be ignored, at least in miR-125a biogenesis.

Impact of race/ethnicity on prognosis in patients who underwent surgery for colon cancer: analysis for white, African, and East Asian Americans

PURPOSE

We retrospectively investigated the impact of race/ethnicity on prognosis in patients who underwent surgery for colon cancer.

METHODS

Surveillance, Epidemiology, and End Results population-based data on 39,210 colon cancer patients without distant metastasis who underwent radical surgery were analyzed. Prognostic impact of race/ethnicity for non-Hispanic white, Hispanic white, African American, and East Asian (Japanese, Chinese, Korean) American patients, and confounding factors of age, sex, registry region, year of diagnosis, tumor, node, metastasis system stage, tumor grade, tumor site, and the number of lymph nodes examined were analyzed by the Cox proportional hazard model. The lymph node count was analyzed and adjusted means were calculated by a generalized multiple regression model with respect to race and other factors.

RESULTS

Significant differences due to race/ethnicity were observed in crude hazard ratios with respect to overall and colon cancer-specific mortality, which persisted even after adjusting for confounding factors. Adjusted hazard ratios of colon cancer-specific mortality for non-Hispanic white, Hispanic white, African American, and East Asian American patients were 1 (reference), 1.01 (95% confidence interval 0.91-1.12), 1.40 (95% confidence interval 1.31-1.50), and 0.83 (95% confidence interval 0.74-0.94), respectively. There were significant differences in crude number of lymph nodes examined among races, which were no longer significant after adjusting for covariates.

CONCLUSIONS

East Asian American patients had significantly better prognosis, while African American patients had worse prognosis than non-Hispanic white patients, despite the identical adjusted number of lymph nodes examined after surgery for colon cancer. This disparity in prognosis among races/ethnicities should be taken into consideration when deciding adjuvant chemotherapy for nonwhite patients.

[Chemoradiation combined with total mesorectal excision for patients with locally advanced rectal cancer]

Rectal cancer is characterized by a high rate of local recurrence. Although it is widely believed that local control results in improved patient outcome, its strategy is still controversial. In Japan, total mesorectal excision (TME) or tumor-specific mesorectal excision (TSME) with pelvic sidewall dissection is regarded as the standard procedure, while TME or TSME with preoperative chemoradiotherapy (CRT) is common in Western countries. Most clinical data have indicated that preoperative CRT is not associated with improved long-term survival but with a lower incidence of local recurrence. In addition, CRT is known to enhance the severity of impaired sphincter function. Currently, trials using CRT regimens with newly developed chemotherapy agents are ongoing to elucidate the effect on the control of distant metastasis. According to clinical reports, the prognosis of Japanese patients undergoing surgery alone is as favorable as that in patients undergoing surgery plus CRT in the West, which implies that CRT is not a necessary treatment but a selective option. The precise prediction of tumor response and advances in CRT regimens resulting in better survival may improve the treatment of rectal cancer in the future.

Expression of l1 cell adhesion molecule and morphologic features at the invasive front of colorectal cancer

To obtain the correlation between morphologic features in the invasive fronts of colorectal cancer (CRC) and L1 cell adhesion molecule (L1CAM) expression, 275 CRCs were assessed with L1CAM immunostaining and 29 CRCs were examined for L1CAM messenger RNA (mRNA) expression. Based on immunostaining, the positive rate of L1CAM expression increased according to the grade of tumor budding (P = .0002) and solid cancer nests (SCNs; P = .0046). L1CAM mRNA levels at the invasive front of the tumor were higher than those at the center of the tumor (median, 3.7-fold). The gap of L1CAM mRNA level between the invasive front and the central area was 7.3-fold in tumors having SCN lesions, whereas it was 1.9-fold in tumors having non-SCN lesions (P = .0004). L1CAM expression was correlated with nodal involvement in protein and mRNA levels (P = .0007 and P = .036, respectively). Tumor regulation of L1CAM expression is associated with morphologic features at the invasive front in CRC.

Actual Status of Distribution and Prognostic Impact of Extramural Discontinuous Cancer Spread in Colorectal Cancer

Purpose

To clarify the prognostic impact of tumor nodules without residual lymph node (LN) structure (ND) in colorectal cancer and to determine optimal categorization of ND in tumor staging.

Patients and Methods

A multicenter, retrospective pathologic review was performed for 1,716 patients with stages I to III curatively resected colorectal cancer treated at 11 institutions between 1994 and 1998. An additional 2,242 patients from nine institutions were enrolled between 1999 and 2003 as a second cohort to validate the results.

Results

LN metastasis (LNM) and ND were observed in 33.7% and 16.0% (smooth-contour nodule [S-ND], 8.2%; irregular-contour nodule [I-ND], 10.7%) of patients in the first cohort. S-ND and I-ND were similarly distributed in the regional area. There was no considerable difference in the impact on survival between S-ND (hazard ratio [HR], 2.7; 95% CI, 1.9 to 3.8) and I-ND (HR, 4.3; 95% CI, 3.3 to 5.8) or between LNM (HR, 4.5; 95% CI, 3.4 to 6.0) and ND (HR, 4.0; 95% CI, 3.1 to 5.3). LNM and ND were similarly associated with the mode of recurrence. Tumor nodules ≥ 5 mm growing with venous/perineural invasion (ND [v/pni+]), judged with 0.61 κ value among 11 observers, had an independent prognostic value for 5-year survival of 42%; similar results were observed in the second cohort.

Conclusion

These results do not support the TNM system in which S-ND is treated differently from I-ND in tumor staging; LNM and ND should be considered together in the same category. The presence of ND (v/pni+) has a considerable adverse prognostic effect.

Optimal margins and lymphadenectomy in colonic cancer surgery

Background

A standard management policy has not yet been established with respect to the extent of lymphadenectomy for colonic cancer.

Methods

A total of 914 consecutive patients who underwent potentially curative surgery for T2–T4 colonic cancer were reviewed retrospectively. The number of lymph nodes (LNs) examined and the potential contributions to the staging accuracy of the distinct area were analysed. The survival benefit of dissection was compared for pericolic (local), mesocolic (intermediate) and main arterial trunk (main) LN.

Results

Removal of the pericolic LNs within 5 cm of the tumour and intermediate LNs resulted in a mean LN number of 15·9, a sensitivity for overall node positivity of 97·5 per cent, and a survival benefit calculated as a therapeutic value index of 31·4 points. The additional removal of LNs more than 5 cm from the tumour and main LNs did not improve the staging accuracy, while adding only 3·4 points to the survival benefit.

Conclusion

Current guidelines may encourage needlessly extensive surgery. Clinical trials to establish the optimal extent of lymphadenectomy are warranted.

Heterogeneity of metalloproteinase expression in colorectal cancer - relation of molecular findings to basic morphology

AIM

To clarify the correlation between morphological features and the mRNA expression of a disintegrin and metalloproteinases (ADAMs) and matrix metalloproteinases (MMPs) in colorectal cancer.

MATERIALS AND METHODS

In 29 colorectal tumors, cancer cells were isolated by laser microdissection, and the mRNA expression of metalloproteinases was compared between the tumor center and the invasive front.

RESULTS

Regarding the central region as the standard, the mRNA levels of ADAM-12, MMP-1, -2, -7, and -9 at the invasive front were up-regulated. The degree of up-regulation was significantly higher in solid cancer nest (SCN)-positive tumors than in SCN-negative tumors for the mRNA levels of ADAM-12, MMP-2, -7, and - 9 (SCN-positive, median 5.1-, 3.9-, 9.9-, and 2.7-fold; SCN-negative 2.0-, 1.0-, 2.4-, and 0.8-fold; p<0.05, respectively).

CONCLUSION

Up-regulation of the mRNA expression of particular metalloproteinases was significantly associated with the SCN at the leading edge of colorectal tumors.

High-risk stage II colon cancer after curative resection

OBJECTIVES

This study was designed to clarify which attributes of stage II colon cancer are associated with tumor recurrence and survival after curative resection, and the effects of adjuvant chemotherapy (ACT).

METHODS

We retrospectively reviewed outcomes and clinicopathological characteristics of 1476 patients with stage II colon cancer who underwent curative resection.

RESULTS

Of 1476 patients, 204 (13.8%) developed recurrence. Macroscopic type, serum CA19-9 levels, venous invasion, emergency operation, and postoperative ileus were independently associated with overall recurrence. Carbohydrate antigen (CA)19-9 levels, the number of dissected lymph nodes (LN), sex, age, ACT, emergency operation, venous invasion, and macroscopic type were independently associated with poor prognosis. Prognosis was significantly better in patients who received ACT than in those who did not. Among patients with extensive venous invasion, those with fewer than 13 dissected LNs, male patients, and patients >50 years old, the prognosis was significantly better in patients who received ACT than in those who did not.

CONCLUSIONS

ACT for stage II colon cancer is recommended to improve the prognosis of patients with extensive venous invasion, patients with fewer than 13 dissected LNs, patients >50 years old, and male patients, particularly patients with more than two of these risk factors.

One-step nucleic acid amplification (OSNA) for the application of sentinel node concept in gastric cancer

PURPOSE

This study was designed to apply safely the sentinel node navigation surgery (SNNS) to the malignancies, an accurate and prompt intraoperative diagnosis of SN is essential, and micrometastasis has been frequently missed by conventional frozen sections. Recently, a novel molecular-based rapid diagnosis for the lymph node (LN) metastases has been developed using (OSNA) in breast cancer, which takes approximately 30 min to obtain a final result. We evaluated the efficacy of OSNA in terms of the intraoperative diagnosis of LN metastasis in patients with gastric cancer.

METHODS

A total of 162 LNs dissected from 32 patients with gastric cancer was included in this study; 45 LNs were pathologically diagnosed as metastatic LNs and 117 LNs were negative. The LNs were bisected; halves were examined with H&E stain, and the opposite halves were subjected to OSNA analyses of CK19 mRNA. The CK19 mRNA expression was examined in the positive or negative metastatic LNs, and the correlation between the tumor volume and CK19 mRNA expression in the metastatic LNs was examined.

RESULTS

The CK19 mRNA expressions in the positive metastatic LNs were significantly higher than those of negative LNs. When 250 copies/μl was set as a cutoff value, the concordance rate was 94.4%, the sensitivity was 88.9%, and the specificity was 96.6%. The OSNA expression was significantly correlated with the estimated tumor volumes in the metastatic LNs.

CONCLUSIONS

The OSNA method is feasible and acceptable for detecting LN metastases in patients with gastric cancer. This should be applied for the intraoperative diagnosis in the SN-navigation surgery in gastric cancer.

Characteristics of recurrence after curative resection for T1 colorectal cancer: Japanese multicenter study

BACKGROUND

Because the rate of recurrence after curative resection for T1 colorectal cancer is low, the characteristics of recurrence remain obscure. This multicenter study attempted to clarify the characteristics of recurrence after curative resection for T1 colorectal cancer.

METHODS

We analyzed the associations between recurrence and various clinicopathological features in 798 patients who had undergone curative resection alone for T1 colorectal cancer at 14 hospitals between 1991 and 1996.

RESULTS

The rate of lymph node metastasis (LNM) in patients with T1 colorectal cancer was 10.5% (84/798), and 18 (2.3%) of the 798 patients developed recurrence during the median follow-up of 7.8 years. The recurrence rates in patients with colon cancer with and without LNM were 3.6 and 1.3%, respectively (p = 0.19). These rates in patients with cancer of the rectum were 25.0 and 1.1% (p < 0.0001). Among various parameters, histological grade (p < 0.0001), location (p = 0.025), LNM (p < 0.0001), and venous invasion (p = 0.0013) were risk factors for recurrence. Among them, LNM (p = 0.0008) and histological grade (p = 0.041) were independent risk factors for recurrence after curative resection for T1 colorectal cancer. Time to recurrence was more likely to be shorter for patients with, than without nodal involvement. In patients with an unfavorable histological grade, all recurrences developed within 1 year.

CONCLUSIONS

The recurrence rate after curative resection for node-negative T1 colorectal cancer was very low. The effectiveness of surveillance to detect recurrence after curative resection for T1 colorectal cancer should be validated in further studies.

[A case of long-term survival after resection of advanced undifferentiated rectal cancer treated by short-term preoperative chemoradiotherapy and postoperative adjuvant chemotherapy]

A 75-year-old man with advanced undifferentiated rectal cancer, diagnosed by endoscopic biopsy, underwent preoperative short-term chemoradiotherapy (whole pelvis, 4 Gy × 5 day with UFT 400 mg/day × 7 day). Tumor size and lymph node swellings were reduced after radiation therapy. Down-staging was achieved from cT3, cN2, cStage III b to cT3, cN1, cStage III a. A curative low anterior resection with D3 lymphadenectomy including lateral lymph node dissection, was performed 4 weeks after the completion of chemoradiotherapy. Pathological findings of resected specimen showed undifferentiated carcinoma with regional lymph node involvement (pT2, pN1, pStage III a). The histological change in response to chemoradiation was evaluated as Grade 2. The postoperative course was uneventful and postoperative adjuvant chemotherapy (UFT+Uzel) was performed for six months (5 courses). No sign of recurrence has been found until 51 months after the operation. Undifferentiated rectal cancer is a rare condition with extremely poor prognosis according to the Japanese literature. Nine cases have been reported so far with only one long-term survivor. This combination of preoperative short-term chemoradiotherapy and adjuvant chemotherapy, which is one of the standard strategies for advanced rectal cancer in Western countries, but not common in Japan, may be a promising option for treatment of undifferentiated rectal cancer.

Risk factors of nodal involvement in T2 colorectal cancer

PURPOSE

Because of the adverse consequences of radical resection of T2 colorectal cancer, criteria are needed for selection of patients who can safely undergo local excision without requiring additional radical surgery. We therefore conducted a retrospective study of patients with T2 colorectal cancer to identify risk factors for nodal involvement that might be used in selecting patients for local excision.

METHODS

We reviewed records from consecutive patients who had undergone curative resection of T2 colorectal cancer at the Department of Surgery, National Defense Medical College, Saitama, Japan, between 1985 and 2005. Data on conventional clinicopathologic variables were retrieved from pathology reports at the time of surgery, and archived slides were evaluated regarding potential risk factors such as extent of poorly differentiated component (grade I-III), myxoid cancer stroma, tumor budding, and growth pattern and invasion depth in the muscularis propria.

RESULTS

A total of 244 patients (139 men and 105 women) treated for T2 colorectal cancer were included. Nodal involvement was found in 7 (8.4%) of 83 patients classified as grade I on the poorly differentiated component vs. 47 (29.2%) of 161 patients classified as grade II or III (P < .001). Of 148 patients negative for myxoid cancer stroma, 30 (16.9%) had nodal involvement vs. 24 (36.4%) of 42 patients who were positive for myxoid cancer stroma (P = .0011). According to multiple variable logistic analysis, significant independent risk factors for nodal involvement included poorly differentiated component (P = .002), myxoid cancer stroma (P = .032), and lymphovascular invasion (P = .022).

CONCLUSIONS

Poorly differentiated component, myxoid cancer stroma, and lymphovascular invasion are significant independent risk factors for nodal involvement in T2 colorectal cancer. We need further study to validate these results on another data set, especially in patients with rectal cancer, and to confirm whether local resection of T2 rectal cancer is able to predict the nodal involvement before laparotomy.

Proposed objective criteria for "grade 3" in early invasive colorectal cancer

To establish objective criteria for "grade 3" (G3) in T1 (TNM staging) colorectal cancer (CRC), a total of 296 T1 CRC cases were reviewed. The incidence of nodal involvement differed most greatly between G3 and non-G3 (21/27 [27%] and 6/162 [3.7%], respectively; P < .0001), when G3 was applied to tumors containing either or both of the following: (1) 10 or more solid cancer nests in the microscopic field of a 4x objective lens and (2) a mucin-producing component fully occupied the microscopic field of a 40x objective lens. Regarding G3, vascular invasion, and tumor budding as indicating the risk of metastasis, nodal involvement rate was 21.0% in the tumors with 1 or more risk factors, whereas it was only 1.7% in the no-risk tumors (P < .0001). In patients treated with local excision only, nodal recurrence occurred in 3 (20%) of 15 risk-positive patients, whereas none of 42 patients without risk factors had nodal recurrence (P = .016). In cases of locally excised T1 CRC, G3 as determined by the proposed criteria, vascular invasion, and budding would comprise a useful combination of parameters for determining the indication for additional laparotomy.

Is total mesorectal excision always necessary for T1-T2 lower rectal cancer?

BACKGROUND

The goal of this multicenter study was to clarify the determinants of local excision for patients with T1-T2 lower rectal cancer.

METHODS

Data from 567 consecutive patients who underwent radical resection for T1-T2 lower rectal cancer at 12 institutions between 1991 and 1998 were reviewed. Rates of lymph node metastasis were investigated using a tree analysis, which was hierarchized using independent risk factors for nodal involvement.

RESULTS

The independent risk factors for lymph node metastasis were female gender, depth of tumor invasion, histology other than well-differentiated adenocarcinoma, and lymphatic invasion. According to the first three parameters that can be obtained preoperatively, only 0.99% of the patients without risk factors had lymph node metastasis. On the other hand, even if the lower rectal cancer was at stage T1, women with histological types other than well-differentiated adenocarcinoma had an approximately 30% probability of having lymph node metastasis. Lymphatic invasion was most useful to predict nodal involvement among patients with T2 lower rectal cancer. The rates of lymph node metastasis in T2 patients with and without lymphatic invasion were 32.9% and 9.1%, respectively.

CONCLUSIONS

Gender is one of the most important predictors for lymph node metastasis in patients with early distal rectal cancer. Three parameters, including depth of tumor invasion, histology, and gender, are useful determinants for local excision. Additional studies are required to establish the minimum optimal treatment for T2 lower rectal cancer.

Growth pattern in the muscular layer reflects the biological behaviour of colorectal cancer

OBJECTIVE

To determine the clinical value of evaluating the cancer morphology in muscularis propria (MP) for colorectal cancer (CRC) patients.

METHOD

A total of 994 patients with advanced CRC were reviewed in terms of two distinctive growth patterns in the MP: (i) horizontal spread between the circular and longitudinal muscle layers (H-spread) and (ii) 'streaming' spread between the muscle bundles of the circular muscle layer (S-spread).

RESULTS

The incidence of H-spread (n = 153) and S-spread (n = 150) showed a positive correlation with tumour-node-metastasis (TNM) stage and both exerted a negative impact on postoperative survival. Adverse morphology in the MP (H-spread and/or S-spread) was consistent with a high grade of vascular invasion and budding in the extramural layer, as also with unfavourable fibrotic stromas in the reactive fibrous zone; the 5-year survival rate in patients with such features was 64.2%, which was lower than that in those without (86.5%, P < 0.0001). Multivariate analysis demonstrated that adverse morphology was an independent prognostic determinant, along with T- and N -stage. As the mode of H-spread, perineural invasion in the myenteric plexus was found to be predominant over lymphatic spread on the basis of S100 and CD34 immunostaining, but neural cell adhesion molecule expression, whether on cancer cells or on neural cells, was not significant for this growth pattern.

CONCLUSION

A particular group of CRCs ingeniously utilizes the thin space between muscle fascicles for development in the MP. Although the biological mechanism remains unknown, this distinctive growth pattern could be a useful indicator to identify CRC patients at high risk of recurrence.

Turnover rate of tear-film lipid layer determined by fluorophotometry

Aim:

This study was performed to independently assess the turnover rates of aqueous and lipid layers of the tear film.

Methods:

Two fluorescent dyes, fluorescein sodium and 5-dodecanoylaminofluorescein (DAF), which is a free-fatty-acid conjugate of fluorescein, were applied to the right eye of 12 healthy volunteers. Fluorescent intensity of the precorneal tear film was measured at the central cornea every minute for 10 min for fluorescein sodium, and every 5 min for 50 min for DAF. The turnover rate was calculated by plotting fluorescent intensity against time in a semilog plot and expressed as %/min.

Results:

Turnover rates of fluorescein sodium and DAF were 10.3 (SD 3.7)%/min and 0.93 (0.36)%/min, respectively. The turnover rate of DAF was significantly lower than that of fluorescein sodium (p<0.05, Mann–Whitney test). The turnover rate of DAF positively correlated with that of fluorescein sodium (r = 0.93, p<0.05).

Conclusion:

Our results indicate that the turnover of lipids in tears is much slower than the aqueous flow of tears, and that this lipid turnover is associated with the aqueous flow of tears in healthy adults.

Enteral refeeding rapidly restores PN-induced reduction of hepatic mononuclear cell number through recovery of small intestine and portal vein blood flows

BACKGROUND

Absence of enteral nutrition (EN) reduces hepatic mononuclear cell (MNC) numbers and impairs their functions. However, enteral refeeding (ER) for as little as 12 hours following parenteral nutrition (PN) rapidly restores hepatic MNC numbers. We hypothesized that changes in small intestine and portal vein blood flows related to feeding route might be responsible for this phenomenon.

METHODS

In experiment 1, mice (n = 19) were randomized to Chow (n = 5), PN (n = 7) or ER (n = 7) groups. The Chow group was given chow ad libitum with intravenous (IV) saline for 5 days. The PN group was fed parenterally for 5 days, while the ER group was re-fed with chow for 12 hours following 5 days of PN. Then, small intestine and portal vein blood flows were monitored and hepatic MNCs were isolated and counted. In experiment 2, the effects of intravenous administration of prostaglandin E(1) (PGE(1)) on hepatic MNC numbers were examined in fasted mice for 12 hours. Mice (n = 28) were randomized to Control (n = 8), PG0 (n = 10), or PG1 (n = 10) groups. The Control group was fed chow ad libitum with IV saline, while the PG0 and PG1 groups were fasted for 12 hours with infusions, respectively, of saline and PGE(1) at 1 microg/kg/minute. Blood flows and hepatic MNC numbers were examined.

RESULTS

Experiment 1: ER restored PN-induced reductions in small intestine and portal vein blood flows and hepatic MNC number to the levels in the Chow group. Small intestine and portal vein blood flows correlated positively with hepatic MNC number. Experiment 2: Fasting decreased small intestine and portal vein blood flows and hepatic MNC number. However, PGE(1) restored portal vein blood flow to the level of the Control group, and moderately increased hepatic MNC number. There was a positive correlation between portal blood flow and hepatic MNC number.

CONCLUSIONS

Reduced small intestine and portal vein blood flows may contribute to impaired hepatic immunity in the absence of EN. ER quickly restores hepatic MNC number through recovery of blood flow in both the small intestine and the portal vein.

Effect of anastrozole and tamoxifen on lipid metabolism in Japanese postmenopausal women with early breast cancer

Endocrine therapies that profoundly decrease estrogen levels potentially have a detrimental effect on the cardiovascular system. This study evaluated the effect on lipid metabolism of one such agent, the new generation aromatase inhibitor anastrozole, compared with tamoxifen, when used as adjuvant treatment in postmenopausal Japanese women with early breast cancer. All patients had completed primary surgery and were randomized to anastrozole 1 mg once daily (n=22) or tamoxifen 20 mg once daily (n=22). Anastrozole significantly reduced levels of triglycerides and remnant-like particle cholesterol, whereas tamoxifen significantly increased these. Activity of lipoprotein lipase and levels of high-density lipoprotein cholesterol significantly increased after anastrozole treatment. In contrast, activity of hepatic triglyceride lipase, also a key enzyme of triglyceride metabolism, significantly decreased following treatment with tamoxifen. We thus conclude that in our study anastrozole had a beneficial effect on lipid profiles of postmenopausal women with early breast cancer after 12 weeks of treatment.

Timing of relapse and outcome after curative resection for colorectal cancer: a Japanese multicenter study

BACKGROUND

The aim of this multicenter study was to clarify the influence of timing of relapse after curative resection for colorectal cancer on prognosis.

METHODS

We enrolled 5,230 consecutive patients who underwent curative resection for colorectal cancer at 14 hospitals from 1991 to 1996. All patients were intensively followed up. Time to relapse (TR) was classified into three groups as follows: group A, TR < or =1 year; group B, TR >1 year and < or =3 years, and group C, TR >3 years. The prognoses after relapse were compared among the three groups.

RESULTS

Of the 5,230 patients, 906 experienced relapse (17.3%). The curative resection rates for recurrent tumors were 35.2% in group A, 46.6% in group B, and 45.1% in group C (p = 0.0045). There were significant differences in the prognoses after relapse among the three TR groups in patients with relapse to the liver (p = 0.0175) and in those with local relapses (p = 0.0021), but not in those with pulmonary or anastomotic recurrence. There were no differences in prognoses after relapse in any recurrence site among the three groups in patients who underwent curative resection for relapse.

CONCLUSION

If patients can undergo curative resection for relapse, they receive a survival benefit regardless of the timing of relapse.

Enteral nutrition rapidly reverses total parenteral nutrition-induced impairment of hepatic immunity in a murine model

BACKGROUND & AIMS

Total parenteral nutrition (TPN) impairs host immunocompetence, a mechanism possibly underlying the high morbidity of infectious complications in critically ill patients. Our recent study demonstrated TPN to reduce the number and function of hepatic mononuclear cells (MNCs) and to worsen survival after intraportal Pseudomonas challenge in mice. The present study examined the duration of enteral nutrition (EN) needed to reverse TPN-induced changes in hepatic MNCs in a murine model.

METHODS

Male ICR mice (6 weeks) received 5 days of TPN followed by 0 (TPN), 12 (EN12), 24 (EN24), 48 (EN48) or 72 (EN72)h of chow feeding. Control mice (Control) were given chow with intravenous saline infusions for 5 days. After nutritional support, hepatic MNCs were isolated and counted. Lipopolysaccharide (LPS) receptor expressions (CD14 and TLR4/MD2) on Kupffer cells were analyzed by flowcytometry. In addition, TPN, EN12, EN48 and control mice were given intraportal Pseudomonas challenge and survival was monitored.

RESULTS

The TPN group was significantly lower in hepatic MNC number and LPS receptor expressions than the Control group. However, EN quickly reversed TPN-induced hepatic impairments in MNC loss within 12h, CD14 expression within 48 h and TLR4/MD2 expression within 24h. Survival of the EN48 group was significantly improved as compared with the TPN and EN12 groups.

CONCLUSIONS

EN rapidly reverses TPN-induced impairment of hepatic immunity along with increased hepatic MNC numbers and LPS receptor expressions on Kupffer cells.

Crucial role for Ser133-phosphorylated form of cyclic AMP-responsive element binding protein signaling in the differentiation and survival of neural progenitors under chronic cerebral hypoperfusion

Various stimuli, such as ischemia/hypoxia enhance newborn cell survival in the subventricular zone and their migration tangentially in chains toward the olfactory bulb. The present study assessed the fate of newborn neurons from subventricular zone to olfactory bulb under conditions of chronic cerebral hypoperfusion, and examined the role of cAMP-responsive element binding protein signaling on the survival of these neurons by using cilostazol, a potent inhibitor of type III phosphodiesterase. Rats underwent bilateral common carotid artery ligation. They were divided into sham-operated (n=70), vehicle- (n=70), and type III phosphodiesterase inhibitor-treated (n=70) groups. Immunohistochemically-stained section for 5-bromodeoxyuridine and a series of neuronal and glial markers were analyzed at days 7, 14, 21 and 28 after hypoperfusion. The reduction of olfactory bulb size gradually progressed in the vehicle group (P<0.05), but not in the sham-operated and type III phosphodiesterase inhibitor-treated group. The subventricular zone of the vehicle-treated rats contained significantly larger numbers of newborn neuroblasts after hypoperfusion, compared with sham-operated rats (P<0.05), but significantly lower numbers in the rostral migratory stream and olfactory bulb (P<0.05). Treatment of rats with type III phosphodiesterase inhibitor increased the number of neuroblasts and enhanced the survival and differentiation of cells (P<0.05). Phosphorylated cAMP-responsive element binding protein within neuroblasts was markedly decreased in the subventricular zone, rostral migratory stream, and olfactory bulb of vehicle-treated rats (P<0.05), but treatment with type III phosphodiesterase inhibitor resulted in recovery of this expression throughout hypoperfusion, leading to enhanced neurogenesis (P<0.05). These effects were abrogated by protein kinase A and C inhibitor. Our results indicated that cAMP-responsive element binding protein signaling is a key mediator of neurogenesis after prolonged hypoperfusion and provide the basis for new regenerative therapies for ischemic brain injury.

Outcomes of surgery alone for lower rectal cancer with and without pelvic sidewall dissection

PURPOSE

The goal of this retrospective multicenter study was to investigate the efficacy of pelvic sidewall dissection for lower rectal cancer.

METHODS

Data from 1,272 consecutive patients who underwent total mesorectal excision for lower rectal cancer in 12 institutions from 1991 through 1998 were reviewed. The rates of local recurrence and survival in patients with pelvic sidewall dissection were compared with those without pelvic sidewall dissection. Logistic regression analysis was used to determine independent risk factors for lymph node metastasis and local recurrence, and the Cox proportional hazards model was used to determine independent prognostic factors.

RESULTS

Of the 1,272 patients, 784 underwent pelvic sidewall dissection. Among them, 117 patients (14.9 percent) had lateral pelvic lymph node metastasis. Risk factors for lateral pelvic lymph node metastasis included female gender, tumor not well-differentiated adenocarcinoma, and perirectal lymph node metastasis. Lateral pelvic and perirectal lymph node metastases were independent risk factors for local recurrence. The Cox proportional hazard model showed age, grade of histology, invasion depth of the tumor, perirectal lymph node metastasis, and lateral pelvic lymph node metastasis to be independent prognostic factors. No significant differences between patients with and those without pelvic sidewall dissection were seen regarding rates of local recurrence (10.5 percent vs. 7.4 percent) or five-year overall survival (75.8 percent vs. 79.5 percent). Although the proportion of patients with advanced stages of disease was greater in patients who had pelvic sidewall dissection, no differences between the two groups were seen in local recurrence even when tumor category was taken into account. However, lack of pelvic sidewall dissection was a predictor of poor prognosis.

CONCLUSIONS

Although pelvic sidewall dissection does not appear to confer overall benefits regarding local recurrence or survival, the effectiveness of pelvic sidewall dissection in specific patient groups remains uncertain. A randomized controlled study is necessary to clarify this issue.