Comparative proteomic studies on the pathogenesis of human ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory disorder primarily affecting the colon mucosa. Its etiology and pathogenesis remain unclear. We used 2-DE and MS to identify differentially expressed proteins among the UC active, UC inactive, nonspecific colitis, and normal colon mucosa. Thirteen down-regulated and six up-regulated proteins were identified. Of the down-expressed proteins, eight (heat-shock protein 90 (HSPA9B), heat-shock protein 60 (HSPD1), H+-transporting two-sector ATPase (ATP5B), prohibitin (PHB), mitochondrial malate dehydrogenase (MDH2), voltage-dependent anion-selective channel protein 1 (VDAC1), thioredoxin peroxidase (PRDX1), and thiol-specific antioxidant (PRDX2)) were mitochondrial proteins, three (ATP5B, MDH2, triosephosphate isomerase) were involved in energy generation, three (PRDX1, PRDX2, SELENBP1) were cellular antioxidants, and six (HSPD1, HSPA9B, PRDX1, PRDX2, PHB, VDAC1) were stress-response proteins. Transmission electron microscopy revealed pathological alterations of mitochondrial ultrastructures even before the global colonocyte changes in the UC colon mucosa. PHB, an essential mitochondrial component protein, was down-expressed in the disease active as well as inactive colon mucosa from the patients of UC, indicative of an early event of mitochondrial changes during UC development. In contrast, aberrant activation of NFAT and ectopic expression of potential immunogenic proteins (tumor rejection antigen 1 and poliovirus receptor related protein 1) were found in the UC-diseased colon mucosa. Our findings suggest the implications of colonocyte mitochondrial dysfunction and perturbed mucosa immune regulation in the pathogenesis of UC and provide potential targets for the development of a new therapy.

Psychiatric morbidity and post-traumatic symptoms among survivors in the early stage following the 1999 earthquake in Taiwan

This study reports the clinical psychiatric presentations and post-traumatic symptoms among 525 survivors at Yu-Chyr District in Nantou County who sought psychiatric service in the first month following the devastating earthquake that struck the central area of Taiwan. All subjects received psychiatric interviews and assessments using the 12-item Chinese Health Questionnaire (CHQ-12) and a checklist for post-traumatic symptoms. The most common psychiatric symptoms reported were insomnia, palpitations, nervousness, and dizziness with headache. Eleven percent of the subjects reported having thought of death or having suicidal ideation. The mean score on the CHQ-12 was 6.43 (S.D.=2.89). The rate of probable psychiatric morbidity as defined by a CHQ-12 score > or =3 was 89.9%. Post-traumatic symptoms were very prevalent, particularly symptoms of re-experiencing the earthquake and hyper-arousal. Factors significantly associated with high psychiatric morbidity were being female, serious destruction of property and house, and personality characteristics of nervousness and obsessiveness. Findings of this study suggest that early psychiatric intervention, including pharmacological treatment for acute stress disorder, is indicated during the early stages following a disastrous earthquake.

Favorable influence of age on tumor characteristics of sporadic colorectal adenocarcinoma: patients 30 years of age or younger may be a distinct patient group

PURPOSE

Age is reported as a risk factor for carcinogenesis, even though age can affect cancer behavior both positively and negatively. Young patients with colorectal cancer reveal different tumor characteristics than average-age and older-age groups, although few studies report the influence of age among the entire range of patient ages. The influence of age on clinicopathologic characteristics of sporadic colorectal cancer was analyzed. Whether an age group with distinct tumor characteristics was present was determined.

METHODS

A total of 5,436 patients who underwent colectomy in a single institute within a seven-year period were studied. Data on clinical and histopathologic features of colorectal cancer were collected from the cancer registry and medical records. These characteristics were analyzed according to ten-year age groups.

RESULTS

Eighty-three patients (1.6 percent) were 30 years of age or younger, whereas 285 (5.5 percent) were 31 to 40 years of age. Most patients (74.6 percent) were 51 to 80 years of age. The proportion of localized tumors (Dukes A and Dukes B) significantly increased as age increased, from 31.3 percent in the 30 years or younger age group to 49 percent in the 80 years or older group (P < 0.001). The proportion of poorly differentiated tumors tended to decreased as age increased (from 16.9 percent in the 30 years or younger group to 6.2 percent in the 80 years or older group; P = 0.009). A similar trend in the proportion of mucin-producing tumors was also observed (36 percent in the younger group vs. 7.5 percent in the older group; P < 0.001). There was no significantly different distribution of tumor locations among the different age groups.

CONCLUSIONS

Age appears to favorably influence the clinicopathological characteristics of sporadic colorectal cancer. As age increased, the characteristics of tumor stage at diagnosis, tumor differentiation, and mucin production improved.

Anterior ankle-foot orthosis effects on postural stability in hemiplegic patients

OBJECTIVES

To evaluate the effects of an anterior ankle-foot orthosis (AFO) on static and dynamic postural stability in hemiplegic patients.

DESIGN

A cross-sectional assessment of hemiplegic subjects with and without an AFO.

SETTING

Outpatient department of a rehabilitation hospital.

PATIENTS

A convenience sample of 24 subjects who had been prescribed an anterior AFO.

OUTCOME MEASURES

Postural sway index and postural symmetry (body weight distribution through the affected leg) when standing were measured as static postural stability. Maximal balance range in anterior-posterior and lateral directions and the affected leg's weight bearing after weight shift to affected side were measured as dynamic postural stability.

RESULTS

When wearing the anterior AFO, there was no significant difference and small effect size (r<0.3) in postural sway index (p = .35), postural symmetry (p = .21), and maximal balance range in anterior-posterior direction (p = .46). There was a significant improvement and large effect size (r>0.5) in lateral weight shifting (p<.01) and weight bearing through the affected leg after weight shifted to the affected side (p<.01).

CONCLUSIONS

The significant effects of the anterior AFO in long-term hemiplegic patients were on lateral weight shifting and weight bearing through affected leg after weight shifted to the affected side. Postural sway, postural symmetry, and anterior-posterior weight shifting were not significantly affected.

Evaluation of prognosis for malignant rectal gastrointestinal stromal tumor by clinical parameters and immunohistochemical staining

PURPOSE

The aim of this study was to identify associated prognostic factors influencing the outcome of curative resection of rectal gastrointestinal stromal tumor.

PATIENTS AND METHODS

Diagnostic immunohistochemical staining with CD34, CD117, S-100, desmin, and muscle-specific actin was performed in 46 consecutive patients with previously diagnosed rectal leiomyosarcoma who underwent curative resection from 1979 to 1999. CD44, Bcl-2, P53, and Ki-67 staining were performed on tumors rediagnosed as gastrointestinal stromal tumor for the prognostic evaluation.

RESULTS

There were 42 (91.3 percent) patients with rectal gastrointestinal stromal tumor (18 females and 24 males; mean age, 58.4 years). Twenty-nine patients underwent radical surgical resections, such as abdominoperineal resection or low anterior resection, whereas the other 13 patients underwent wide local excision, such as transrectal excision or Kraske's operation. Sixteen tumors were classified as high-grade gastrointestinal stromal tumors, and 26 as low-grade. No tumor had a positive P53 stain. Twenty-seven patients (64.3 percent) developed recurrence or metastasis postoperatively (median follow-up, 52 months). The one-year, two-year, and five-year disease-free survival rates were 90.2 percent, 76.7 percent, and 43.9 percent, respectively. Of these patients with recurrence, subsequent resections in 12 patients with local recurrence, transarterial tumor embolism or STI-571 chemotherapies in 3 patients with distant mestastases were performed. The one-year, two-year, and five-year overall survival rates were 97.4 percent, 94.3 percent, and 83.7 percent, respectively. Bcl-2 (P = 0.007) and histologic grade (P = 0.05) in disease-free survival analysis and age < 50 years (P = 0.03) and tumor size > 5 cm (P = 0.02) in overall survival analysis were independent prognostic factors. The group with wide local excision had a higher local recurrence rate than that of the radical resection group (77 percent vs. 31 percent, P = 0.006), despite smaller tumors (4.5 vs. 7.2 cm, P = 0.05). There was no difference in the incidence of distant metastasis between the two groups.

CONCLUSION

Younger age (< 50 years), higher histologic tumor grade, positive Bcl-2 status, and larger tumors (> 5 cm) were factors associated with significantly poorer prognoses for rectal gastrointestinal stromal tumor. Radical resection was superior to wide local excision in the prevention of local recurrence, but not that of distant metastases.

Risk factors for lymph node metastasis in pT1 and pT2 rectal cancer: a single-institute experience in 943 patients and literature review

BACKGROUND

Local excision has become an alternative for radical resection in rectal cancer for selected patients. The purpose of this study was to assess the clinicopathologic factors determining lymph node metastasis (LNM) in patients with T1-2 rectal cancer.

METHODS

Between January 1995 and December 2009, a total of 943 patients with pT1 or pT2 rectal adenocarcinoma received radical resection at a single institution. Clinicopathologic factors were evaluated by univariate and multivariate analyses to identify risk factors for LNM.

RESULTS

A total of 943 patients (544 men and 399 women) treated for T1-2 rectal cancer were included in this study. LNM was found in 188 patients (19.9%). In multivariate analysis, lymphovascular invasion (LVI; P < 0.001, hazard ratio 11.472), poor differentiation (PD; P = 0.007, hazard ratio 3.218), and depth of invasion (presence of pT2; P = 0.032, hazard ratio 1.694) were significantly related to nodal involvement. The incidence for LNM lesions in the presence of LVI, PD, and pT2 was 68.8, 50.0, and 23.1%, respectively, while that for pT1 carcinomas with no LVI or PD was 7.5%.

CONCLUSIONS

LVI, PD, and pT2 are independent risk factors predicting LNM in pT1-2 rectal carcinoma.

Clinical significance of signet ring cell rectal carcinoma

BACKGROUND AND AIMS

Signet ring cell carcinoma of the rectum (SCCR) is a rare type of rectal carcinoma. This study examined the clinical significance of SCCR.

PATIENTS AND METHODS

From our medical records we retrospectively identified 61 SCCR patients and compared their clinical data and outcomes to those of 144 consecutive patients with non-SCCR mucinous rectal adenocarcinomas (NSMR) and 2,414 consecutive patients with nonmucinous rectal adenocarcinomas (NMR).

RESULTS

. The incidence of SCCR was 1.39% of rectal cancers. Mean patient age at onset of SCCR (48.1years, range 15-80) was significantly lower than that for NSMR (57.4 years, 9-88) and NMR (62.6 years, 12-94). The proportion of late stage (TNM III+IV) tumors was significantly higher in SCCR (90%) than in NSMR (69%) and NMR (48%). There were more tumors located in the lower rectum in SCCR (46%) than in NSMR (34%) and NMR (29%). SCCR tumors were significantly larger (5.68+/-3.84 cm) than NSMR (4.27+/-1.78 cm) and NMR tumors (3.76+/-1.71 cm). A higher percentage of patients with SCCR (42.6%) received abdominoperineal resection for treatment. In tumors with TNM stage IV the rate of tumor spread via the hematogenous route was significantly lower in SCCR (18.5%) than in NSMR (43.5%) and in NMR (69%). The rate of tumor spread via seeding to the peritoneum was lower in SCCR (22.2%) than in NSMR (43.5%) but higher than in NMR (2.7%). The rate of tumor spread via the lymphatic route was higher in SCCR (44.4%) than in NSMR (26.1%) and significantly higher than in NMR (12.3%). The 1-, 2-, and 5-year overall SCCR survival rates were 73.9%, 36.3%, and 23.3% respectively, which were significantly poorer than those of NSMR and NMR. For the 28 stage III and R0 SCCR tumors the 1-, 2-, and 5-year disease-free survival rates of SCCR were 84.0%, 44.2%, and 30.3%, respectively, which are comparable with general data of stage III rectal cancer in the world.

CONCLUSION

Diffuse infiltration of signet ring cells enhances the tendency of mucinous carcinomas of the rectum in more local extension and easier lymphatic spreading but not at peritoneal seeding. Although SCCR had the poorest prognosis, this outcome may be due to the advanced tumor stage rather than histology itself.

Pre-operative serum albumin level substantially predicts post-operative morbidity and mortality among patients with colorectal cancer who undergo elective colectomy

The quantitative relationship between serum albumin level and surgical outcomes has not been clearly established. This study included 3732 patients with colon cancer who underwent a potentially curative colectomy. Post-operative mortality and morbidity were analysed according to the patients' demographic data, pre-operative comorbidities, and tumour-related factors. Age, asthma, renal impairment, and albumin level were significantly associated with post-operative morbidity and mortality in the multivariate analyses. Logistic regression analysis revealed linear relationships of post-operative morbidity and mortality with albumin level. The morbidity and mortality rates decreased by 7.3% and 15.6%, respectively, for each 0.1 g/dL increase in albumin level. This finding remained significant in the hypoalbuminaemia subgroup but not in the normoalbuminaemia subgroup. That is, the morbidity and mortality rates significantly decreased by 8.7% and 17.7%, respectively (both P < 0.001), in the former group and decreased by 2.7% (P = 0.112) and 11.6% (P = 0.092), respectively, in the latter group. This study demonstrated that serum albumin level linearly predicted the post-operative morbidity and mortality among the colorectal cancer patients. Pre-operative serum albumin level may therefore be used as a continuous rather than a categorical marker of disease severity, especially among patients with hypoalbuminaemia.

Identification of a fibronectin binding protein from Streptococcus mutans

The interaction of viridans streptococci with components of the extracellular matrix (ECM) plays an important role in the pathogenesis of infective endocarditis. We have identified a surface protein of Streptococcus mutans which binds the ECM constituent fibronectin (Fn). Initially, we found that S. mutans could adsorb soluble Fn in plasma, but with lower efficiency than Streptococcus pyogenes. In addition, S. mutans could bind immobilized Fn in a dose-dependent manner when tested using an enzyme-linked immunosorbent assay. Crude extracts of cell wall-associated proteins or extracellular proteins from S. mutans MT8148 specifically bound Fn through a protein with the molecular mass of ca. 130 kDa, as detected by far-Western immunoblotting. The candidate Fn binding protein (FBP-130) was purified to near homogeneity by using Fn coupled Sepharose 4B affinity column chromatography. A rabbit polyclonal antibody against FBP-130 reacted specifically with a protein of molecular mass of ca. 130 kDa in both cell wall and extracellular fractions, and the abundance of FBP was higher in the former than in the latter fractions. The purified FBP bound specifically to immobilized Fn, whereas the binding of soluble Fn to coated FBP could only be detected in the presence of high concentrations of Fn. The purified FBP, as well as anti-FBP immunoglobulin G, inhibited the adherence of S. mutans to immobilized Fn and endothelial cells (ECV304) in a dose-dependent manner. These results demonstrated that FBP-130 mediated the adherence of S. mutans specifically to Fn and endothelial cells in vitro. The characteristics of S. mutans and FBP-130 in binding Fn confirmed that viridans streptococci adopt different strategies in their interaction with ECM.

Risk factors associated with posthemorrhoidectomy secondary hemorrhage: a single-institution prospective study of 4,880 consecutive closed hemorrhoidectomies

PURPOSE

Posthemorrhoidectomy secondary hemorrhage is a rare but serious complication after hemorrhoidectomy. The determination of risk factors for this complication may provide information to improve outcome. A prospective study was conducted to determine the risk factors associated with posthemorrhoidectomy secondary hemorrhage.

METHODS

We studied 4,880 patients who underwent an elective closed hemorrhoidectomy by 9 proctologists in a single institution between January 1994 and July 1996. The variables analyzed included age, gender, surgeon, surgeon's seniority, suture material, aseptic preparation, and use of antibiotics. The logistic regression model was used to assess the independent association of variables with posthemorrhoidectomy secondary hemorrhage.

RESULTS

Among the 4,880 patients, 45 (0.9 percent) developed posthemorrhoidectomy secondary hemorrhage. The mean interval from operation to the onset of secondary hemorrhage was 8.8 (range, 5-19) days. Multivariate analysis revealed that patient's gender and individual surgeons were both independently associated with risk of hemorrhage. Male patients were more likely than females to develop posthemorrhoidectomy secondary hemorrhage (relative risk, 2.1; 95 percent confidence interval, 1.1-4.1; P = 0.021). The posthemorrhoidectomy secondary hemorrhage rates among individual surgeons ranged from 0.2 to 2.4 percent (P = 0.003).

CONCLUSION

Our data suggest that male patients are more likely to develop posthemorrhoidectomy secondary hemorrhage than female patients and that intersurgeon variability is highly correlated with this risk.

PTPRT and PTPRD Deleterious Mutations and Deletion Predict Bevacizumab Resistance in Metastatic Colorectal Cancer Patients

Background: Bevacizumab-based regimens are used as standard treatments for colorectal cancer. Unfortunately, there are no established predictive markers for bevacizumab response. Methods: Tumor samples from 36 metastatic colorectal cancer patients treated with bevacizumab plus chemotherapy were analyzed by next-generation sequencing of all coding exons of more than 400 genes. Single gene and signaling pathway analyses were performed to correlate genomic data with response. Results: Among the genes most frequently mutated in our cohort, only mutations in PTPRT, a phosphatase involved in JAK/STAT signaling, were associated with response status, with deleterious mutations being enriched in non-responders. Pathway analysis revealed that deleterious mutations in genes of the JAK/STAT pathway, namely in PTPRT and the related gene PTPRD, correlated with resistance. Mutations in RTK/PI3K/RAS, Wnt and TGFβ pathways did not associate with response. Lack of response was observed in all patients with deleterious mutations or copy number loss of PTPRT/PTPRD (n = 10), compared to only 30.8% (n = 8) of patients without such alterations (relative risk, 3.25; 95% CI, 1.83–5.79, p = 0.0003). Similarly, PTPRT/PTPRD deleterious alterations were associated with shorter progression-free survival, an association that was retained in multivariate analysis (HR, 3.33; 95% CI, 1.47–7.54; p = 0.0038). Conclusion: Deleterious alterations in PTPRT/PTPRD are potential biomarkers for bevacizumab resistance.

Subclinical neurotoxicity of mercury vapor revealed by a multimodality evoked potential study of chloralkali workers

Pattern visual, brainstem auditory, and somatosensory evoked potential (EP) studies were performed on 26 chloralkali workers. The intensity of mercury vapor exposure in these workers was estimated from the individual working history. Mercury levels in blood, urine, and hair were determined with atomic absorption spectrometry. The EP findings were compared with those from individually matched normal subjects. In brainstem auditory and somatosensory EP studies, prolonged neural conduction times in the central nervous system (CNS) were found in workers exposed to mercury vapor. In the pattern visual EP study, mercury workers had higher interpeak amplitudes. Findings of this study suggested that chronic exposure to mercury vapor would affect the CNS functions. A multimodality EP study is a useful adjunct in evaluation of chronic mercury neurotoxicity, especially in an epidemiological study.

Role of body mass index in colon cancer patients in Taiwan

AIM: To determine the effect of body mass index (BMI) on the characteristics and overall outcome of colon cancer in Taiwan.

METHODS: From January 1995 to July 2003, 2138 patients with colon cancer were enrolled in this study. BMI categories (in kg/m²) were established according to the classification of the Department of Health of Taiwan. Postoperative morbidities and mortality, and survival analysis including overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS) were compared across the BMI categories.

RESULTS: There were 164 (7.7%) underweight (BMI < 18.5 kg/m²), 1109 (51.9%) normal-weight (BMI = 18.5-23.9 kg/m²), 550 (25.7%) overweight (BMI = 24.0-26.9 kg/m²), and 315 (14.7%) obese (BMI ≥ 27 kg/m²) patients. Being female, apparently anemic, hypoalbuminemic, and having body weight loss was more likely among underweight patients than among the other patients (P < 0.001). Underweight patients had higher mortality rate (P = 0.007) and lower OS (P < 0.001) and DFS (P = 0.002) than the other patients. OS and DFS did not differ significantly between normal-weight, overweight, and obese patients, while CSS did not differ significantly with the BMI category.

CONCLUSION: In Taiwan, BMI does not significantly affect colon-CSS. Underweight patients had a higher rate of surgical mortality and a worse OS and DFS than the other patients. Obesity does not predict a worse survival.

Increased densities of resting and activated microglia in the dentate gyrus follow senile plaque formation in the CA1 subfield of the hippocampus in the triple transgenic model of Alzheimer's disease

Alzheimer's disease (AD) is an irreversible neurodegenerative disease that is characterised by the presence of β-amyloid (Aβ) plaques, neurofibrillary tangles (NFTs) and synaptic loss specifically in brain regions involved in learning and memory such as the neocortex and the hippocampus. Aβ depositions in the form of neuritic plaques trigger activation of microglia that is believed to be a common neuropathological feature of AD brains. As an integral part of the hippocampus, the dentate gyrus (DG) plays an important role in cognitive function. Although post-mortem studies suggest later involvement of the DG into the AD progression, changes in microglia have not been studied in this subfield of the hippocampus. In the present study the numerical density (Nv, #/mm(3)) of both resting (identified by tomato lectin staining) and activated (identified by Mac-1 immunoreactivity) microglia was analysed in the molecular layer (ML) of the DG in the triple transgenic (3xTg-AD) mouse model of AD at different ages (9, 12 and 18 months). The 3xTg-AD mouse model of AD showed a significant increase in the Nv of resting (by 75%) and activated (by 67%) at 18 months of age compared to non-Tg controls. These results indicate a complex microglial remodelling during AD progression.

Association of sex, adiposity, and diet with HDL subclasses in middle-aged Chinese

BACKGROUND

There is limited information regarding the associations of lifestyle factors and sex with HDL subclasses containing apolipoprotein (apo) A-I (Lp A-I) and both apo A-I and apo A-II (Lp A-I:A-II).

OBJECTIVE

We sought to examine the relations between 2 major HDL subclasses and sex, menopausal status, nutrient intakes, and adiposity.

DESIGN

We conducted interviews and measured blood variables in 409 government employees aged 40-59 y in Taiwan.

RESULTS

Women (n = 203) had significantly higher concentrations of HDL cholesterol, Lp A-I, and Lp A-I:A-II than did men (n = 206). Postmenopausal women (n = 72) had higher concentrations of HDL cholesterol, Lp A-I, and Lp A-I:A-II than did premenopausal women (n = 131). Body mass index and waist-to-hip ratio were strong predictors of and exerted an independent additive effect on Lp A-I concentrations in both men and women. However, body adiposity was associated with Lp A-I:A-II concentrations only in men. Waist-to-hip ratio was an independent determinant of Lp A-I but not of Lp A-I:A-II in men and postmenopausal women after adjustment for age, body mass index, smoking, and diet. Although there were relatively weak associations between dietary factors and both HDL subclasses (r = 0.01-0.26) in men and women according to bivariate analyses, multiple regression models showed that total fat, saturated fat, and cholesterol intakes were significantly correlated with HDL cholesterol and both Lp A-I and Lp A-I:A-II in men, but not in women.

CONCLUSION

Our data suggest that body adiposity and dietary fat consumption affect 2 major HDL subclasses differently depending on subject sex and menopausal status.

Utility of 2-fluoro-2-deoxy-D-glucose positron emission tomography in managing patients of colorectal cancer with unexplained carcinoembryonic antigen elevation at different levels

PURPOSE

Serum carcinoembryonic antigen elevation without detectable relapse during colorectal cancer follow-up presents a challenge. This study was designed to evaluate the utility of fluorine-18-labeled 2-fluoro-2-deoxy-D-glucose positron emission tomography in colorectal cancer patients with unexplained carcinoembryonic antigen elevation at different levels.

METHODS

Thirty-seven colorectal cancer patients referred for positron emission tomography after primary surgery who had serum carcinoembryonic antigen levels >5 ng/ml and negative or equivocal conventional imaging studies were analyzed. Patient status was determined by histopathology and/or clinical follow-up. Grouping as disease-free, potentially resectable, or advanced disease was performed. The management impact was defined as the percentage of patients with a true-positive positron emission tomography result.

RESULTS

The sensitivity, specificity, and accuracy of positron emission tomography for relapse detection were 89, 89, and 89 percent, respectively. The management impact was 68 percent. In 24 patients with carcinoembryonic antigen levels <25 ng/ml, positron emission tomography helped correct patient grouping in 20 patients (83 percent), including 8 in the disease-free group, 5 in the potentially resectable group, and 7 in the advanced-disease group. In 13 patients with carcinoembryonic antigen levels >25 ng/ml, positron emission tomography identified 8 patients in the advanced-disease group and 1 patient in the potentially resectable group but missed 2 patients with relapse and undergrouped 2 patients in the advanced-disease group as potentially resectable.

CONCLUSIONS

2-fluoro-2-deoxy-D-glucose positron emission tomography can help triage patients for appropriate management with unexplained carcinoembryonic antigen elevation <25 ng/ml. For patients with unexplained elevation of carcinoembryonic antigen >25 ng/ml, the utility of positron emission tomography is mainly to confirm the presence of advanced disease and occasionally to identify potentially resectable lesions.

Preoperative Carcinoembryonic Antigen as a Poor Prognostic Factor in Stage I-III Colorectal Cancer After Curative-Intent Resection: A Propensity Score Matching Analysis

BACKGROUND

Preoperative carcinoembryonic antigen (CEA) has yet to be used as a prognostic or adjuvant chemotherapy factor for colorectal cancer (CRC).

METHODS

This retrospective cohort study included all stage I-III CRC patients with different preoperative serum CEA levels (≤ 5, 5-10, and > 10 ng/ml) at a single center between 1995 and 2010. Propensity score matching was performed in a 1:1 ratio between the two elevated CEA groups (5-10 ng/ml and > 10 ng/ml) and in a 1:2 ratio between the elevated and non-elevated groups (≤ 5 ng/ml), with a caliper of 0.05.

RESULTS

After exclusion and matching, 3857 patients had preoperative CEA levels ≤ 5 ng/ml, 1121 patients had CEA levels between 5 and 10 ng/ml, and 1121 patients had CEA levels > 10 ng/ml. Elevated preoperative CEA showed an increased risk of overall survival (5-10 ng/ml: hazard ratio [HR] 1.376; > 10 ng/ml: HR 1.523; both p < 0.001), cancer-specific survival (5-10 ng/ml: HR 1.404; > 10 ng/ml: HR 1.712; both p < 0.001), and recurrence free interval (5-10 ng/ml: HR 1.190; > 10 ng/ml: HR 1.468; both p < 0.05). Patients with negative lymph node staging (LNs) and CEA > 10 ng/ml, as well as those with positive LNs and CEA ≤ 5 ng/ml, showed similar overall survival (5-year survival: 72% vs. 69%; p = 0.542) and recurrence free intervals (19.9 vs. 21.72 months; p = 0.662).

CONCLUSIONS

A preoperative CEA level can be an independent prognostic factor for stage I-III CRC after curative resection. Patients with negative LNs and preoperative CEA level > 10 ng/ml should be considered for intensive follow-up or adjuvant chemotherapy.

CBB1003, a lysine-specific demethylase 1 inhibitor, suppresses colorectal cancer cells growth through down-regulation of leucine-rich repeat-containing G-protein-coupled receptor 5 expression

PURPOSE

Lysine-specific demethylase 1 (LSD1) was highly expressed in several malignancies and had been implicated in pathological processes of cancer cells. However, the role of LSD1 in colorectal cancer (CRC) carcinogenesis, prognosis and treatment remains uncharacterized.

METHODS

In this study, we examined LSD1 expression in paraffin-embedded CRC specimens from 295 patients, including 65 patients with paired samples of colorectal carcinoma, adjacent adenoma and normal colorectal tissues. Using an LSD1 inhibitor, CBB1003, as a probe, we studied the association between LSD1 and leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), a CRC stem cell marker involved in carcinogenesis. The anti-tumor effects of CBB1003 on CRC cells were also examined.

RESULTS

LSD1 expression was significantly elevated in colorectal tumor tissues compared with adjacent adenoma and normal colorectal tissues (P < 0.001), and LSD1 levels were significantly correlated with an advanced AJCC T stage (P = 0.012) and distant metastasis (P = 0.004). CBB1003 inhibited CRC cell proliferation and colony formation. In cultured CRC cells, inhibiting LSD1 activity by CBB1003 caused a decrease in LGR5 levels while overexpression of LGR5 reduced CBB1003-induced cell death. We also observed the inactivation of β-catenin/TCF signaling after CBB1003 treatment, consistent with the positive correlations among LSD1, LGR5, β-catenin and c-Myc expression in human colon tumor and adenoma tissues.

CONCLUSION

Our result suggested that LSD1 overexpression promotes CRC development and that the LSD1 inhibitor inhibits CRC cell growth by down-regulating LGR5 levels and inactivates the Wnt/β-catenin pathway. Thus, LSD1 and its inhibitor might provide a new target or a useful strategy for therapy of CRC.

Short- and medium-term outcomes of intracorporeal versus extracorporeal anastomosis in laparoscopic right colectomy: a propensity score-matched study

BACKGROUNDS

Though better short-term outcomes were frequently reported, differences in specimen parameters and the rate of subsequent peritoneal recurrence between intracorporeal anastomosis (IA) and extracorporeal anastomoses (EA) for laparoscopic right hemicolectomy have not been analyzed. We aimed to compare the pathologic differences and oncological outcomes between these two approaches.

METHODS

We retrospectively analyzed 217 consecutive patients who underwent laparoscopic right hemicolectomies from September 2016 to April 2018 and classified them into IA and EA groups, based on the approach used. Propensity score matching analysis was performed, after which 101 patients were included in each group with the patients matched for demographics, tumor stage, and localization.

RESULTS

The IA group had a longer operative time, shorter length of stay, shorter time to first flatus and tolerating a soft diet, and better pain scale scores at postoperative day 3. No inter-group differences in conversion, postoperative complication, mortality, or readmission rates were found. The IA group had a longer resected colon length (23.67 vs. 19.75 cm, p = 0.010) and nearest resected margin (7.51 vs. 5.40 cm, p = 0.010) for cancer near the hepatic flexure. There are comparable 3-year overall survival (87.7% vs. 89.6%, p = 0.604) and disease-free survival (75.0% vs. 75.7%, p = 0.842) between the IA and EA groups. The rate of peritoneal recurrence was similar between the two groups (5.9% vs. 7.9%, p = 0.580).

CONCLUSIONS

The overall survival, disease-free survival, and the rate of peritoneal recurrence were comparable between the IA and EA procedures. IA ensures better recovery and comparable complications to EA and achieved a more precise tumor excision; thus, IA can be considered a safe procedure for patients with right-sided colon lesions.