Ethnic disparity in breast cancer survival in southern Thai women.

BACKGROUND: Breast cancer has the highest incidence in women of all cancers and its burden is expected to continue to increase worldwide, especially in middle-income countries such as Thailand. The southern region of Thailand is unique in that it is comprised of 30% Muslims, whereas the rest of Thailand is 95% Buddhist. Breast cancer incidence and survival differ between these religious groups, but the association between clinical subtype of breast cancer and survival has not yet been assessed. METHODS: Here we characterized differences in breast cancer survival with consideration to clinical subtype by religious group (Muslim Thai and Buddhist Thai women). We compared distributions of age, stage and clinical subtype and assessed overall survival by religion. RESULTS: Our findings show that Muslim Thai women with breast cancer are diagnosed at a younger age, at later stages and have shorter overall survival times compared to Buddhist Thai women with breast cancer. We also observe a higher proportion of triple negative tumors characterized in Muslim Thai women. CONCLUSIONS: Our findings confirm previous studies that have shown lower survival rates in Muslim Thai women compared to Buddhist women with breast cancer and offer novel information on subtype distribution. To date, this is the first study assessing clinical subtypes in southern Thailand by religious status. IMPACT: Our findings are critical in providing information on the role of clinical subtype in cancer disparities and provide evidence from the Southeast Asian region for global studies on breast cancer survival.

In vivo biocompatibility and degradation of novel Polycaprolactone-Biphasic Calcium phosphate scaffolds used as a bone substitute.

BACKGROUND: Biocompatibility and degradation of poly ε-caprolactone (PCL)-Biphasic Calcium Phosphate (BCP) scaffolds fabricated by the "Melt Stretching and Compression Molding (MSCM)" technique were evaluated in rat models. OBJECTIVES: Degradation behaviors and histological biocompatibility of the PCL-20% BCP MSCM scaffolds and compare with those of PCL-20% ß-tricalcium phosphate (TCP) scaffolds commercially fabricated by Fused Deposition Modeling (FDM) were evaluated. METHODS: The study groups included Group A: PCL-20% BCP MSCM scaffolds and Group B: PCL-20% TCP FDM scaffolds, which were implanted subcutaneously in twelve male Wistar rats. On day 14, 30, 60 and 90, dimensional changes of the scaffolds and their surrounding histological features were assessed using Micro-Computed Tomography (µ-CT) and histological analysis. Changes of their molecular weight were assessed using Gel Permeation Chromatography (GPC). RESULTS: Formation of collagen and new blood vessels throughout the scaffolds of both groups increased with time with low degrees of inflammation. The µ-CT and GPC analysis demonstrated that the scaffolds of both groups degraded with time, but, their molecular weight slightly changed over the observation periods. All results of both groups were not significantly different. CONCLUSIONS: The PCL-20% BCP MSCM scaffolds were biocompatible and biodegradable in vivo. Their properties were comparable to those of the commercial PCL-20% TCP scaffolds.

Correlation between Serum SCCA and CYFRA 2 1-1, Tissue Ki-67, and Clinicopathological Factors in Patients with Esophageal Squamous Cell Carcinoma.

BACKGROUND: Squamous cell carcinoma antigen (SCCA) and CYFRA 21-1 have been reported as useful tumor markers for esophageal squamous cell carcinoma (ESCC), but no information has yet been reported about the relationship between these serum tumor markers and tissue proliferative activity (Ki-67) in ESCC patients. OBJECTIVE: To study the correlation between SCCA, CYFRA 21-1, Ki-67, and clinicopathological factors in ESCC patients. MATERIAL AND METHOD: Pretreatment SCCA and CYFRA 21-1 serum levels were measured, while the expression of Ki-67 was assessed on tumor tissue. The associations between these biomarkers, clinicopathological factors, and overall survival were analyzed. RESULTS: One hundred sixty six patients participated in this study. Elevated SCCA and CYFRA 21-1 were found in 78.9% and 50.0% of the patients, respectively, while 42.8% had both serum markers elevated. The SCCA and CYFRA 21-1 levels were not correlated (p = 0.128) to each other nor to age, sex, T N, M location, grade, or Ki-67. High Ki-67 expression levels were significantly correlated with T4 (p = 0.010), M1 (p = 0.010), and poor grade (p = 0.015) but not to age, sex, N, or location. Levels of SCCA, CYFRA 21-1, and Ki-67, alone or in any combination, were not correlated to survival of patients. CONCLUSION: The authors showed that Ki-67 in tumor tissue is probably a more reliable marker than serum SCCA and CYFRA 21-1 in predicting the clinical course of ESCC.

Anticancer and Cancer Prevention Effects of Piperine-Free Piper nigrum Extract on N-nitrosomethylurea-Induced Mammary Tumorigenesis in Rats.

Piper nigrum (P. nigrum) is commonly used in traditional medicine. This current study aimed to investigate the anticancer and cancer preventive activity of a piperine-free P. nigrum extract (PFPE) against breast cancer cells and N-nitrosomethylurea (NMU)-induced mammary tumorigenesis in rats. The cytotoxic effects and the mechanism of action were investigated in breast cancer cells using the MTT assay and Western blot analysis, respectively. An acute toxicity study was conducted according to the Organization for Economic Co-operation and Development guideline. Female Sprague-Dawley rats with NMU-induced mammary tumors were used in preventive and anticancer studies. The results showed that PFPE inhibited the growth of luminal-like breast cancer cells more so than the basal-like ones by induction of apoptosis. In addition, PFPE exhibited greater selectivity against breast cancer cells than colorectal cancer, lung cancer, and neuroblastoma cells. In an acute toxicity study, a single oral administration of PFPE at a dose of 5,000 mg/kg body weight resulted in no mortality and morbidity during a 14-day observation period. For the cancer preventive study, the incidence of tumor-bearing rats was 10% to 20% in rats treated with PFPE. For the anticancer activity study, the growth rate of tumors in the presence of PFPE-treated groups was much slower when compared with the control and vehicle groups. The extract itself caused no changes to the biochemical and hematologic parameters when compared with the control and vehicle groups. In conclusion, PFPE had a low toxicity and a potent antitumor effect on mammary tumorigenesis in rats.

Repairing calvarial defects with biodegradable polycaprolactone-chitosan scaffolds fabricated using the melt stretching and multilayer deposition technique.

The ability to repair bone defects of polycaprolactone-chitosan scaffolds containing 20% chitosan (PCL-20%CS) fabricated using the melt stretching and multilayer deposition (MSMD) technique was assessed and compared with commercial scaffolds. Two calvarium defects of 11 mm in diameter were created in each of the fifteen New Zealand white rabbits. The PCL-20%CS scaffolds were implanted in one site (group A) while another site was performed with PCL-tricalcium phosphate (TCP) scaffolds containing 20% TCP (PCL-20%TCP) fabricated by fused deposition modeling technique (FDM) (group B). At two, four and eight weeks thereafter, new bone regeneration within the defects was assessed using histomorphometric and micro-computed tomography (µ-CT) analysis. The result of histological sections demonstrated that chronic inflammatory reaction was generally detected along scaffolds of group A, but it was not found in group B. Over 8 weeks, the µ-CT analysis indicated that the average amount of new bone of group A was slightly less than that of group B (p>0.05). In conclusion, efficacy of the PCL-20%CS MSMD scaffolds for repairing bone defects was less than that of the PCL-20%TCP FDM scaffolds. However, MSMD scaffolding is still the technique of choice, but needed some modifications.

Cell type classifiers for breast cancer microscopic images based on fractal dimension texture analysis of image color layers.

Having a classifier of cell types in a breast cancer microscopic image (BCMI), obtained with immunohistochemical staining, is required as part of a computer-aided system that counts the cancer cells in such BCMI. Such quantitation by cell counting is very useful in supporting decisions and planning of the medical treatment of breast cancer. This study proposes and evaluates features based on texture analysis by fractal dimension (FD), for the classification of histological structures in a BCMI into either cancer cells or non-cancer cells. The cancer cells include positive cells (PC) and negative cells (NC), while the normal cells comprise stromal cells (SC) and lymphocyte cells (LC). The FD feature values were calculated with the box-counting method from binarized images, obtained by automatic thresholding with Otsu's method of the grayscale images for various color channels. A total of 12 color channels from four color spaces (RGB, CIE-L*a*b*, HSV, and YCbCr) were investigated, and the FD feature values from them were used with decision tree classifiers. The BCMI data consisted of 1,400, 1,200, and 800 images with pixel resolutions 128 × 128, 192 × 192, and 256 × 256, respectively. The best cross-validated classification accuracy was 93.87%, for distinguishing between cancer and non-cancer cells, obtained using the Cr color channel with window size 256. The results indicate that the proposed algorithm, based on fractal dimension features extracted from a color channel, performs well in the automatic classification of the histology in a BCMI. This might support accurate automatic cell counting in a computer-assisted system for breast cancer diagnosis.

Comparative proteomic analysis of oral squamous cell carcinoma and adjacent non-tumour tissue from Thailand.

OBJECTIVE: The study was aimed at analysing and identifying the proteins that are differentially expressed in oral squamous cell carcinoma (OSCC) compared to adjacent non-tumour tissue. MATERIALS AND METHODS: Two-dimensional (2D) sodium dodecyl sulphate-polyacrylamide gel electrophoresis accompanied by mass spectrometry (matrix-assisted laser desorption/ionisation-time-of-flight mass spectrometry and liquid chromatography-tandem mass spectrometry) was used to analyse and identify the differentially expressed proteins in 10 pairs of tumours and adjacent non-tumour tissues from five cases of early-stage and five cases of late-stage OSCC. The statistical differences of the protein spots were analysed by the Wilcoxon signed-rank test. A validation study using immunohistochemistry and quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) was performed. RESULTS: A total of 68 proteins (63 up-regulated, five down-regulated) were differentially expressed in early-stage disease, and 39 proteins (37 up-regulated, two down-regulated) were significantly altered in late-stage disease. Among these, 14 proteins were altered in both groups. A total of 44 proteins were identified, including heat shock proteins (HSPs: Hsp90, HSPA5 and HSPA8), keratins (K1, K6A and K17), tubulin, cofilin 1, 14-3-3σ and metabolic enzymes. These proteins are involved in various cellular processes essential for cell growth, survival and cell migration. The validation study on α-tubulin and 14-3-3σ using immunohistochemistry and KIAA1199 expression using real-time RT-PCR confirmed the results in proteomics analysis. CONCLUSIONS: The study identified many proteins, both known and unknown, for cancer cell processes. At least two proteins, KIAA1199 and Horf6, are novel for oral cancer.

The prognostic value of p53, Bcl-2 and Bax expression in laryngeal cancer.

OBJECTIVE: Determine the prognostic value of p53, Bcl-2 and Bax expression in cancer of the larynx. MATERIAL AND METHOD: Ninety-four patients diagnosed with laryngeal squamous cell carcinoma were analyzed for 5-year overall survival in relation to immunohistochemical expression of p53, Bcl-2, and Bax proteins. RESULTS: The present study included 86 males and eight females with a mean age of 65.1 years. Half of the patients (51%) were in stages III and IV. Radiation (44.7%) and radiation plus surgery (40.4%) were the main treatments. The frequency of p53, Bcl-2, and Bax expression was 58.1%, 18.5%, and 87.2%, respectively. The 5-year overall survival rate was 49.7%. Univariate analysis revealed that T-stage, N-stage and treatment were significantly associated with 5-year overall survival. In the multivariate Cox regression, T-stage, treatment, and Bcl-2 expression were significantly associated with survival. Positive Bcl-2 expression was associated with better survival (Hazard ratio 0.23, 95% CI 0.06-0.81). CONCLUSION: The positive Bcl-2 expression is an independent prognostic marker in laryngeal squamous cell carcinoma.

Differential protein expression in primary breast cancer and matched axillary node metastasis.

Axillary lymph node (ALN) metastasis is a key step of tumor progression in breast cancer and is associated with an unfavorable prognosis. However, the mechanisms of this process are not well understood. Proteomic technologies have led to identification of specific protein markers and a better understanding of the cellular processes. To explore this, differential protein expression was analyzed between node-positive breast carcinoma and node-negative breast carcinoma (11 samples) and between primary breast carcinoma and matched metastatic ALN (five pairs) using a combination of 2D-SDS-PAGE and LC-MC/MS. Of the total 678 protein spots, 19 proteins were up-regulated and 3 proteins were down-regulated in node-positive breast carcinomas compared to node-negative breast carcinomas. Four up-regulated proteins were identified, namely annexin 5, carbonic anhydrase I, peroxiredoxin 6 and proteasome α2 subunit. For proteins altered in metastatic ALN compared to primary tumors, 6 of 14 up-regulated proteins were identified: heat shock 70 kDa protein 5, protein disulfide isomerase, prolyl 4-hydroxylase ß subunit precursor, lactate dehydrogenase B, triosephosphate isomerase 1 and ß-tubulin and 5 of 23 down-regulated proteins were identified including 90 kDa heat shock protein, chain A apo-human serum transferrin, chain A α1-antitrypsin, enolase 1 and macrophage migration inhibitory factor. Immunohistochemistry showed stronger immunostaining for ß-tubulin in metastatic ALN compared to primary breast tumor. All of the identified proteins function in various processes involved in cell survival and growth. Our results suggest that these processes are critical for tumor progression and metastasis and the proteins identified could be candidate markers of clinical usefulness.

Specific intronic p53 mutation in esophageal squamous cell carcinoma in Southern Thailand.

AIM: To investigate p53 mutations in esophageal cancer in a high-risk population, and correlate them with smoking, alcohol consumption and betel chewing. METHODS: One hundred and sixty-five tumor samples of esophageal squamous cell carcinoma (ESCC) obtained from a university hospital in Songkhla province, Southern Thailand were investigated for p53 mutations in exons 5-8, using polymerase chain reaction-single strand conformation polymorphism analysis, followed by direct sequencing. A polymerase chain reaction-restriction fragment length polymorphism (RFLP) assay was additionally used to confirm possible germline mutation in intron 6. A history of risk habits was obtained by interviews. The association between risk habits and mutation frequency was evaluated using the χ(2) test. RESULTS: The studied specimens were from 139 male and 26 female patients with ESCC, treated at Songklanagarind Hospital. Most of the patients were smokers (86.7%) and alcohol consumers (72.73%), and 38.3% were betel chewers. Forty-three mutations of the p53 gene were detected in 25.5% (42/165) of tumor samples. Mutations were most commonly found in exon 5 (25.6%) and exon 8 (25.6%). Mutations in the hot-spot codon 248 were found in four cases (9.3% of all mutations). G:C→C:G (30.23%), G:C→A:T (27.90%) and G:C→T:A (16.28%) were the prevalent spectra of mutations. Unexpectedly, among 10 intronic mutations, eight cases harbored a similar mutation: G→C substitution in intron 6 (nucleotide 12759, GenBank NC_000017). These were additionally confirmed by the RFLP technique. Similar mutations were also detected in their matched blood samples using RFLP and direct sequencing, which suggested germline mutations. There was no significant correlation between risk habits and p53 mutation frequency. CONCLUSION: A proportion of Thai ESCC patients harbored specific intronic p53 mutations, which might be germline mutations. Further studies are needed to explore this novel finding.

P16(INK4A) expression in Bowen's disease and Bowenoid papulosis.

BACKGROUND: Bowen's disease (BD) is a skin carcinoma in situ occurring over the entire body surface. It shares similar histopathological features with Bowenoid papulosis (BP) of the genitalia, but differs in etiology and clinical course. Increased p16(INK4A) (p16) tumor suppressor protein expression has been demonstrated in relation to the progression of cutaneous squamous neoplasms. OBJECTIVE: To evaluate the difference in p16 expression between Bowen's disease and Bowenoid papulosis. MATERIAL AND METHOD: Biopsies of 46 cases of BD in the period 1994 - 2003 and 14 cases of BP during 1987 - 2003 in the Anatomical Pathology Unit, Department of Pathology, Faculty of Medicine, Prince of Songkla University, Thailand were studied by immunohistochemical methods using the P16 kit (CINTec Histology Kit, clone E6H4, Code-Nr. K5334, DakoCytomation, Denmark). Nuclear/cytoplasmic immunoreactivity in more than 10% of neoplastic cells was considered positive. RESULTS: P16 expression was positive in 37 of 46 BD cases (80.4%) which was higher than that of BP (6 of 14 cases or 42.9%) (p value < 0.05, Chi-square test). The expression among the three groups of BD: extragenital (28 of 35), chronic arsenical-related (7 of 8) and genital lesions (2 of 3) was not significantly different (p value = 0.734, Chi-square test). CONCLUSION: P16 expression was more frequent in BD than BP. This suggests a possible association between p16 expression and tumorigenesis of these lesions.

Prognostic significance of Bax, Bcl-2, and p53 expressions in cervical squamous cell carcinoma treated by radiotherapy.

OBJECTIVE: The objective was to determine the prognostic significance of the immunohistochemical expressions of Bax, Bcl-2, and p53 in squamous cell carcinoma of the uterine cervix treated by radiotherapy alone. METHODS: One hundred and seventy-four cases of squamous cell carcinoma of the cervix (stage Ib-IVa) diagnosed between January 1996 and December 1998 were investigated for Bax, Bcl-2, and p53 expressions and were correlated to the patients' survival. RESULTS: The mean age of the patients was 54.1 with a range of 29-82 years. There were 23 cases with stage I (13.2%), 99 stage II (56.9%), 51 stage III (29.3%), and 1 case with stage IV (0.6%). The 5-year disease-free survival (DFS) was 70.50% and overall survival (OS) was 65.95%. Bax, Bcl-2, and p53 expressions were seen in 68.4%, 25.9%, and 77.6% of cases, respectively. In multivariate analysis by Cox's regression, age, stage, Bax, and Bcl-2 expressions appeared to be independent prognostic predictors of DFS. Bax expression was associated with good survival (hazard ratio, 0.47) while Bcl-2 expression was associated with poor survival (HR, 2.51). In addition, a combination of Bcl-2+/Bax+ was significantly associated with poorer DFS compared to Bcl-2-/Bax+ (HR 3.55). However, none of the markers or combinations was associated with OS. CONCLUSIONS: Evaluation of Bax and Bcl-2 expressions and their co-expression provide independent prognostic information for the clinical course of the disease and therefore could be developed as a prognostic indicator for cervical cancer.

p53 mutations in betel-associated oral cancer from Thailand.

The p53 mutations in betel-related oral cancer have been studied but the results may be confounded by tobacco and alcohol due to tobacco components in the quid or concomitant habits of smoking and drinking. In this study, p53 mutations in tumors from Thai betel chewers who neither smoke nor drink were studied in comparison to tumors from smokers/drinkers. PCR-SSCP analysis and direct sequencing on exon 5-8 were performed. Mutations were detected in 11.8% (8/68) of betel-related tumors and 7 of 8 mutations were G:C to A:T transitions. By contrast, mutations were found in 22.4% (13/58) of smoking/drinking-related tumors with various base substitutions. The results demonstrated different mutation profiles between the two exposed groups. The type of mutation detected in betel chewers suggested a possible role of areca-specific nitrosamine as a causative carcinogen.

Lifestyle habits and genetic susceptibility and the risk of esophageal cancer in the Thai population.

The association of lifestyle habits and polymorphism of ADH2 and ALDH2 genes with the risk of esophageal cancer in Thai population was investigated in a hospital-based case-control study: 202 cases and 261 controls. The results of multivariate logistic analysis showed that alcohol consumption >60g/day, smoking >10 cigarettes/day and chewing betel >or=10 quids/day significantly increased risk (odds ratio (OR) 5.84, 95% confidence interval (CI) 3.15-10.83; 4.65, 95% CI 1.99-10.84; and 4.68, 95% CI 2.05-10.72, respectively). ADH2*1/*1 also increased the risk significantly (OR 1.56, 95% CI 1.01-2.39) while ALDH2 did not (OR of ALDH2*1/*2 1.57, 95% CI 0.89-2.76). However, the combined at risk genotypes, ADH2*1/*1 and ALDH2*1/*2 increased risk to four-fold. In addition, significant gene-environment interaction was found. Heavy drinkers >60g/d harboring ADH2*1/*1 or ALDH2*1/*2 had about an 11-fold increased risk.