T-Cell Immunoglobulin Mucin 3 Expression on Tumor Infiltrating Lymphocytes as a Positive Prognosticator in Triple-Negative Breast Cancer / 한국유방암학회지

PURPOSE: T-cell immunoglobulin and mucin domain-containing molecule 3 (TIM-3) is an emerging immune response molecule related to T-cell anergy. There has been tremendous interest in breast cancer targeting immune checkpoint molecules, especially in the triple-negative breast cancer (TNBC). This study was designed to investigate TIM-3 expression on tumor infiltrating lymphocytes (TILs), its relationships with clinicopathological para-meters and expression of programmed death receptor 1 (PD-1)/programmed death receptor ligand 1 (PD-L1), and its prognostic role. METHODS: Immunohistochemistry on tissue microarray blocks produced from 109 samples of invasive ductal carcinoma type TNBC was performed with antibodies toward TIM-3, PD-1, PD-L1 and breast cancer-related molecular markers. Associations between their expression and clinicopathological parameters as well as survival analyses were performed. RESULTS: TIM-3 was expressed in TILs from all 109 TNBCs, consisting of 17 cases ( 51%). High TIM-3 was significantly correlated with younger patients (p=0.0101), high TILs (p=0.0029), high tumor stage (p=0.0018), high PD-1 (p=0.0001) and high PD-L1 (p=0.0019), and tended to be associated with higher histologic grade, absence of extensive in situ components and microcalcification. High TIM-3 expression was significantly associated with a combinational immunophenotype group of high PD-L1 and high PD-1 (p < 0.0001). High TIM-3 demonstrated a significantly better disease-free survival (DFS) (p < 0.0001) and longer overall survival (OS) (p=0.0001), together with high TILs and high PD-1. In univariate survival analysis, high TIM-3 showed reduced relapse risk (p < 0.0001) and longer OS (p=0.0003), together with high PD-1 expression. In multivariate analysis, high TIM-3 was statistically significant in predicting prognosis, showing better DFS (hazard ratio [HR], 0.0994; 95% confidence interval [CI], 0.0296–0.3337; p=0.0002) and longer OS (HR, 0.1109; 95% CI, 0.0314–0.3912; p=0.0006). CONCLUSION: In this study, we demonstrate that TIM-3 expression is an independent positive prognostic factor in TNBC, despite its association with poor clinical and pathologic features.

Education Level Is a Strong Prognosticator in the Subgroup Aged More Than 50 Years Regardless of the Molecular Subtype of Breast Cancer: A Study Based on the Nationwide Korean Breast Cancer Registry Database / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study investigated the role of the education level (EL) as a prognostic factor for breast cancer and analyzed the relationship between the EL and various confounding factors. MATERIALS AND METHODS: The data for 64,129 primary breast cancer patients from the Korean Breast Cancer Registry were analyzed. The EL was classified into two groups according to the education period; the high EL group (≥ 12 years) and low EL group ( 50 years (hazard ratio, 0.626; 95% confidence interval [CI], 0.577 to 0.678) but not in the subgroup aged ≤ 50 years (hazard ratio, 0.941; 95% CI, 0.865 to 1.024). The EL was a significant independent factor in the subgroup aged > 50 years according to multivariate analyses. The high EL group showed more favorable clinicopathologic features and a higher proportion of patients in this group received lumpectomy, radiation therapy, and endocrine therapy. In the high EL group, a higher proportion of patients received chemotherapy in the subgroups with unfavorable clinicopathologic features. The EL was a significant prognosticator across all molecular subtypes of breast cancer. CONCLUSION: The EL is a strong independent prognostic factor for breast cancer in the subgroup aged > 50 years regardless of the molecular subtype, but not in the subgroup aged ≤ 50 years. Favorable clinicopathologic features and active treatments can explain the main causality of the superior prognosis in the high EL group.

Malignant Adenomyoepithelioma of the Breast and Responsiveness to Eribulin / 한국유방암학회지

Adenomyoepithelioma (AME) of the breast is an uncommon tumor characterized by its dual differentiation into luminal cells and myoepithelial cells. In most cases these tumors have a benign clinical course, but distant metastases have been reported. We present the case of a 51-year-old woman diagnosed with malignant AME. The patient underwent a right modified radical mastectomy, and pathological examination confirmed the diagnosis of malignant AME. Ten months after the operation, multiple hepatic, pleural, and abdominal wall metastases were detected. A number of palliative chemotherapeutic agents were tried, including anthracycline and taxanes. However, the disease continued to progress, and superior vena cava syndrome developed as a result of direct tumor invasion. The patient received salvage eribulin monotherapy. After two cycles of this treatment, her clinical symptoms were ameliorated, and a computed tomography scan showed a partial response. Eribulin chemotherapy was thus effective in treating malignant AME in this case.

Reliability of Reconstructed Breast Flap after Chemotherapy and Radiotherapy in Immediate Breast Reconstruction

BACKGROUND: Postmastectomy adjuvant therapy is used to prevent locoregional recurrence and improve overall breast cancer specific survival rates. However, it can adversely affect the cosmetic results of reconstruction. Therefore, the authors examined flap stability and patients' satisfaction with immediate breast reconstruction after adjuvant therapy. METHODS: We retrospectively reviewed the medical records of 204 patients from January 2006 to November 2011. For complication rates, the authors categorized the patients who underwent the immediate breast reconstruction into 4 groups: adjuvant chemotherapy and radiotherapy group, adjuvant chemotherapy only group, adjuvant radiotherapy only group, and the group that did not undergo adjuvant therapy. For comparison of patients' satisfaction, the study was performed with an additional 16 patients who had undergone delayed breast reconstruction. RESULTS: Regarding complication rates, the group that had undergone adjuvant therapy showed no significant difference compared to the group that did not undergo adjuvant therapy. In evaluating the patients' satisfaction, there was no significant difference. CONCLUSIONS: Even after adjuvant therapy, immediate breast reconstruction showed good results with respect to flap stability and patients' satisfaction. Immediate breast reconstruction and adjuvant therapy is a safe and useful option for breast cancer patients.

Nodular Fasciitis of the Chest Wall as seen on Breast Sonography: This Clinically Simulated Palpable Breast Cancer

Nodular fasciitis is a rapidly growing benign soft tissue tumor that is related to the fascia and this tumor is generally seen in young and middle aged adults. It is often seen as a subcutaneous solitary nodule in an upper extremity. Clinically, it is often mistaken for a malignancy. We present here a rare case of nodular fasciitis of the chest wall and that was observed on breast sonography (US) and this lesion clinically simulated palpable breast cancer. US may be helpful for evaluating a chest wall lesion that is misunderstood to be a breast lump. So, if the lesion's location is vague, US can reveal the exact location and characteristics of the mass. Although the incidence of nodular fasciitis is rare, nodular fasciitis should be considered in the differential diagnosis when a lesion is located in the chest wall.

Use of Antidepressants in Patients with Breast Cancer Taking Tamoxifen / 한국유방암학회지

Tamoxifen, a selective estrogen modulator has been used for more than three decades to treat all stages of estrogen receptor (ER)-positive breast cancer and to prevent the disease. Tamoxifen is a pro-drug that requires metabolic activation to 4-hydroxytamoxifen and 4-hydroxy-N-desmethyltamoxifen (endoxifen) to elicit its pharmacological activity. Endoxifen has identical properties and potency with 4-hydroxytamoxifen, but is present in concentrations up to 10-fold higher than 4-hydroxytamoxifen. The cytochrome P450 2D6 (CYP2D6) enzyme plays a key role in converting tamoxifen into its active metabolites with significantly greater affinity for the ER and greater ability to inhibit cell proliferation. Genetic variants in the CYP2D6 gene may result in CYP2D6 enzymes with reduced or null activity, thereby decreasing the anti-cancer effect. In addition to genetic inactivation of CYP2D6, inhibitors of CYP2D6, including some antidepressants to treat hot flashes or depression in patients with breast cancer, may also alter enzyme activity and negatively affect the outcomes of patients receiving adjuvant tamoxifen. This article reviews and discusses the following issues: tamoxifen metabolism, antiproliferative effects of tamoxifen and its metabolites, CYP2D6 genetic polymorphisms, treatment for hot flashes and depression in breast cancer, and the pharmacological interactions between tamoxifen and antidepressants via CYP2D6. Although routine CYP2D6 testing is not recommended yet, coadministration of potent or intermediate CYP2D6 inhibitors in women taking tamoxifen should be avoided.

Clinical Outcomes in Patients with Triple-negative Breast Cancer and Brain Metastases / 한국유방암학회지

PURPOSE: Patients with triple-negative breast cancer (TNBC) are known to carry an increased risk of distant metastasis and poor survival. The principal objective of this study was to investigate survival after brain metastases in patients with TNBC. METHODS: The authors retrospectively evaluated clinical data obtained from 66 patients who had been diagnosed with breast cancer and brain metastasis from 2003 to 2009. Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth receptor-2 (HER2) statuses were determined via immunohistochemical staining. TNBCs were defined as those that were ER-negative, PR-negative, and HER2-negative. The time interval from initial diagnosis to brain metastasis and overall survival after brain metastasis was evaluated via the Kaplan-Meier method. RESULTS: Twenty four (40.0%) of 60 patients were diagnosed with TNBC. The clinicopathologic characteristics did not differ between the TNBC and non-TNBC patients. The disease-free survival durations of the TNBC and non-TNBC subjects were 17.9 and 25.6 months, respectively (p=0.135). The time intervals from initial diagnosis to brain metastasis were 25.5 and 43.7 months, respectively (p=0.027). The time intervals from distant metastasis to brain metastasis were 8.4 and 19.5 months, respectively (p=0.006). Overall survival durations from brain metastasis to death were 4.3 and 7.6 months, respectively (p=0.046). CONCLUSION: Patients with TNBC were more likely to develop brain metastasis earlier, and exhibit poor overall survival. Triple receptor status may be utilized as a prognostic marker for breast cancer patients with brain metastasis.

Non-Mass Image-Forming Low Echoic Areas on Breast US: Pathologic Correlation

PURPOSE: We wanted to analyze the mammographic and clinical findings of the non-mass image-forming low echoic areas seen on breast ultrasonography (US) and investigate their pathologic results. MATERIALS AND METHODS: Sixty-nine patients with 72 non-mass image-forming low echoic areas seen on breast US and who had undergone mammography and biopsy were included in this study. The mammographic findings were divided into 2 groups: 1) the negative or probably benign group and 2) the suspicious for malignancy group. The US findings were divided into 3 groups: focal, segmental and diffuse distributions. The clinical findings were divided into 2 groups: the non-palpable and palpable groups. We investigated the pathologic results according to each group. RESULTS: Of the 72 lesions, 49 (68.1%) were benign and 23 (31.9%) were malignant. On the mammography, 42 (93.3%) of the 45 negative or probably benign findings and 7 (25.9%) of 27 suspicious for malignancy findings were pathologically benign (p < 0.001). On the US, 38 (76%) of the 50 focal distributions and 11 (52.4%) of 21 segmental distributions were benign (p = 0.090). Thirty (73.2%) of the 41 nonpalpable lesions and 19 (61.3%) of the 31 palpable lesions were benign (p = 0.609). CONCLUSIONS: A non-mass image-forming low echoic area seen on breast US was malignant at a higher rate when it was found in conjunction with suspicious mammographic finding. There was no significant correlation between the distribution of the non-mass image-forming low echoic areas on US or their palpability and the pathologic results.

The Galectin 3 Expression in Benign and Malignant Breast Tumor

PURPOSE: Galectin 3 is a beta-galactoside binding protein that is involved in various biological processes such as cell adhesion, migration, cell growth, tumor progression and metastasis. Although the precise acting mechanisms of Galectin 3 are unclear, it have been reported that the expression of Galectin 3 may related to tumor progression and metastasis. We investigated the immunohistochemical expression of Galectin 3 in 57 cases of benign and malignant breast neoplasm to evaluate the relation of a Galectin 3 expression to malignancy of breast neoplasm and the acting mechanism of Galectin 3. METHODS: Twenty fibroadenomas, 7 intraductal papillomas, 10 intraductal carcinomas and 20 invasive ductal carcinomas were studied. Immunostaining of Galectin 3 was evaluated in comparison with that of the internal controls, and the intensity of immunostaining was semiquantitatively graded on an intensity scale of 0 to 3. RESULTS: The normal ductal epithelium of the breast showed strong immunoreactivity with an intensity 2 to 3. The staining gradually and significantly decreased in accordance with the histopathological type and tumor progression from a fibroadenoma, intraductal papilloma, ductal carcinoma in situ and invasive ductal carcinoma (P<0.001). In particular, the expression of galection-3 was prominently decreased in invasive ductal carcinoma. CONCLUSION: The galectin-3 expression pattern suggests that progression from benign breast tumor to malignant breast tumor leads to a reduced expression of galectin-3.

The Effectiveness of Progressive Tension Suture at Latissimus Dorsi Muscle Harvest

PURPOSE: The latissimus dorsi muscle flap is a versatile flap used in a variety of reconstructive procedures. The most common complication of LD muscle flap is donor site seroma, reported to occur in 20 to 79 percent of cases. The formation of dead space under the flap is intimately associated with seroma formation. The authors think that the use of progressive tension suture at closing donor site can decrease the formation of dead space and ultimately reduce the incidence of donor site seroma. METHODS: A retrospective review was performed with 38 patients who underwent latissimus dorsi muscle harvest for breast reconstruction from March 2003 to September 2004. Progressive tension sutures were used during donor site closure in 22 patients. This group was compared with controls group(16 patients) who underwent latissimus dorsi muscle harvest without using this technique. Operation time, length of hospital stay, period of drainage, complication, and satisfaction about postoperative scar of donor site were examined. RESULTS: The average length of hospital stay was 10.2 days and 12.7 days, and the mean duration of drainage were 7.3 days and 11.7 days in each progressive suture group and control group. These results were statistically significant (p<0.05). In the 22 patients who underwent progressive tension suture, none had seroma, hematoma or skin necrosis. In control group(16 patients), there happened one seroma formation and one partial skin necrosis. These complications were healed by aspiration of seroma and wound revision. The patients' satisfaction was not statistically significant, but the higher points were given by the patients who underwent progressive tension suture. CONCLUSION: This technique, progressive tension suture, is an effective method to reduce or eliminate donor site seroma, which is the most common complication associated with latissimus dorsi muscle harvest.

Expression of Topoisomerase II alpha and Ki-67 in Invasive Mammary Carcinoma and Their Clinicopathologic Implication

PURPOSE: Various prognostic indicators have been identified for mammary carcinomas, but the issue of their significance remains unsettled. The prognostic impact of c-erb B2, Ki-67 and topoisomerase II alpha expression was investigated in relation to prognostic factors for carcinomas of the breast and to the tumor cell growth fraction. METHODS: One hundred eighteen cases of invasive mammary carcinoma were investigated by immunohistochemical staining for c-erb B2, topoisomerase II alpha, and Ki-67. Clinicopathologic parameters were compared with the expression pattern and incidence of c-erb B2, topoisomerase II alpha and Ki- 67 in invasive mammary carcinoma. RESULTS: C-erb B2 showed significant correlation with topoisomerase II alpha (P<0.05), but others were not significant. Topoisomerase II alpha and Ki-67 index closely paralleled each other, indicating that both reflect the proliferate activity of tumor cells and were associated with high nuclear and histological grade, ER and PR expression (P<0.05). CONCLUSION: These results indicate that ki-67 and topoisomerase II alpha proteins might play a role in tumor progression of breast carcinoma. The Ki-67 and topoisomerase II alpha index may be proliferate factors of breast cancer. In addition, the increase expression of Ki-67 and topoisomerase II alpha and hormone receptor were closely correlated each other, and could be used as factors suggesting poor prognosis in breast carcinoma.

Subcellular Localization of p27(kip1) in Breast Cancer and Its Prognostic Significance

BACKGROUND: p27 is a member of the cyclin-dependent kinase (CDK) inhibitors that arrest the progression of the cell cycle; thus, it acts as a tumor suppressor gene. The loss or decrease of p27 protein is frequently seen and this has an independent prognostic potential for many human cancers. p27 is functionally inactivated through accelerated proteolysis and cytoplasmic sequestration. Cytoplasmic mislocalization of p27 by abnormal phosphorylation in the tumor cells doesn't allow it to bind and inhibit nuclear cyclin/CDK targets. METHODS: We examined the p27 protein expression in 86 cases of invasive ductal carcinoma of the breast via immunohistochemical staining to evaluate the subcellular localization of p27 and its relationship with the clinicopathologic features and the prognostic factors. RESULTS: The nuclear expression of p27 was noted in 48.9% of the tumors, a combined nuclear and cytoplasmic expression was noted in 20.9%, a cytoplasmic expression was noted in 12.8%, and a negative expression was noted in 17.4%. The decreased nuclear expression and/or cytoplasmic mislocalization of p27 were statistically correlated with the nuclear grade (p=0.001), histologic grade (p=0.036), tumor size (p=0.033), lymph node metastasis (p=0.043), ER (p=0.001), and PR (p=0.001) status, while they were not correlated with patient age, stage, HER2, p53, and Ki67. CONCLUSIONS: The breast tumors showing both decreased nuclear expression and cytoplasmic mislocalization of p27 are associated with a deranged cell cycle via functional inactivation and also with poor prognostic factors. It is expected that p27 can be a promising anticancer target molecule for the treatment of breast cancer.

The Clinical Significance of Normal Mammograms and Normal Sonograms in Patients with Palpable Abnormalities of the Breast

PURPOSE: We wanted to evaluate the clinical significance of normal mammograms and normal sonograms in patients with palpable abnormalities of the breast. MATERIALS AND METHODS: From Apr 2003 to Feb 2005, 107 patients with 113 palpable abnormalities who had combined normal sonographic and normal mammographic findings were retrospectively studied. The evaluated parameters included age of the patients, the clinical referrals, the distribution of the locations of the palpable abnormalities, whether there was a past surgical history, the mammographic densities and the sonographic echo patterns (purely hyperechoic fibrous tissue, mixed fibroglandular breast tissue, predominantly isoechoic glandular tissue and isoechoic subcutaneous fat tissue) at the sites of clinical concern, whether there was a change in imaging and/or the physical examination results at follow-up, and whether there were biopsy results. This study period was chosen to allow a follow-up period of at least 12 months. RESULTS: The patients' ages ranged from 22 to 66 years (mean age: 48.8 years) and 62 (58%) of the 107 patients were between 41 and 50 years old (58%). The most common location of the palpable abnormalities was the upper outer portion of the breast (45%) and most of the mammographic densities were dense patterns (BI-RADS Type 3 or 4: 91%). Our cases showed similar distribution for all the types of sonographic echo patterns. 23 patients underwent biopsy; all the biopsy specimens were benign. For the 84 patients with 90 palpable abnormalities who were followed, there was no interval development of breast cancer in the areas of clinical concern. CONCLUSION: Our results suggest that we can follow up and prevent unnecessary biopsies in women with palpable abnormalities when both the mammography and ultrasonography show normal tissue, but this study was limited by its small sample size. Therefore, a larger study will be needed to better define the negative predictive value of combined normal sonographic and mammographic findings.

The Clinical Significance of Normal Mammograms and Normal Sonograms in Patients with Palpable Abnormalities of the Breast

PURPOSE: We wanted to evaluate the clinical significance of normal mammograms and normal sonograms in patients with palpable abnormalities of the breast. MATERIALS AND METHODS: From Apr 2003 to Feb 2005, 107 patients with 113 palpable abnormalities who had combined normal sonographic and normal mammographic findings were retrospectively studied. The evaluated parameters included age of the patients, the clinical referrals, the distribution of the locations of the palpable abnormalities, whether there was a past surgical history, the mammographic densities and the sonographic echo patterns (purely hyperechoic fibrous tissue, mixed fibroglandular breast tissue, predominantly isoechoic glandular tissue and isoechoic subcutaneous fat tissue) at the sites of clinical concern, whether there was a change in imaging and/or the physical examination results at follow-up, and whether there were biopsy results. This study period was chosen to allow a follow-up period of at least 12 months. RESULTS: The patients' ages ranged from 22 to 66 years (mean age: 48.8 years) and 62 (58%) of the 107 patients were between 41 and 50 years old (58%). The most common location of the palpable abnormalities was the upper outer portion of the breast (45%) and most of the mammographic densities were dense patterns (BI-RADS Type 3 or 4: 91%). Our cases showed similar distribution for all the types of sonographic echo patterns. 23 patients underwent biopsy; all the biopsy specimens were benign. For the 84 patients with 90 palpable abnormalities who were followed, there was no interval development of breast cancer in the areas of clinical concern. CONCLUSION: Our results suggest that we can follow up and prevent unnecessary biopsies in women with palpable abnormalities when both the mammography and ultrasonography show normal tissue, but this study was limited by its small sample size. Therefore, a larger study will be needed to better define the negative predictive value of combined normal sonographic and mammographic findings.

The Risk Factors Associated with Lymphedema after Axillary Dissection for Breast Cancer

PURPOSE: We wanted to evaluate the risk factors for developing lymphedema following axillary lymph node dissection in breast cancer patients. METHODS: Ninety-six patients who underwent axillary dissection for breast cancer were followed-up for up to 1 year. Lymphedema was assessed using a serial circumferential measurement method. More than a 2 cm difference in circumference was considered as clinically significant lymphedema. The effects of age, the body mass index (BMI), the cancer stage, chemotherapy, radiotherapy, the location of cancer and creating a latissimus dorsi (LD) flap on the development of lymphedema were analyzed. RESULTS: The incidence of lymphedema was increased with the advancing cancer stage. Radiotherapy was found to increase the incidence of lymphedema. Patients who had received an LD flap showed a lower incidence of lymphedema. CONCLUSION: These results could be useful as a clinical guideline for creating a management plan for postoperative lymphedema. Because there are some differences in the results between all the relevant reports, including ours, further research is needed in the form of a large, multi-center, long-term study.

The Effects of Obesity for Laparoscopy- Assisted Distal Gastrectomy in Patient with Early Gastric Cancer

Purpose: Laparoscopy-assisted distal gastrectomy (LADG) has recently been accepted as a feasible and acceptable method for early gastric cancer surgery. Surgeons have long suspected that obesity might increase the intra-operative or postoperative complications. We set out to clarify the effects of obesity on LADG for early gastric cancer treatment. METHODS: We retrospectively reviewed 97 patients who had undergone LADG for early gastric cancer between May 1998 and March 2003. The degree of obesity was based on the Body Mass Index (BMI, kg/m2), with patients assigned to two groups: normal BMI (BMI <23 kg/m2) and high BMI (BMI= 23 kg/m2). RESULTS: There were no significant differences between the normal and high BMI groups in terms of patients' characteristics, surgical outcomes and postoperative courses, postoperative complication and operation time. However, there was a significant statistical difference in the operation time among the latter four groups (P=0.004). And the male with high BMI group took particularly a longer operation time than female groups with normal BMI (P=0.006) and high BMI (P=0.013). Conclusion: In LADG patients with early gastric cancer, obesity may affect the operation time, and the male high BMI group takes particularly a longer operation time than the female groups.

Laparoscopy-Assisted Distal Gastrectomy with Systemic Lymphadenectomy for Early Gastric Cancer in Elderly Patients

PURPOSE: We evaluated the validity of laparoscopy-assisted distal gastrectomy (LADG) with systemic lymphadenectomy for early gastric cancer in elderly patients compared with younger patients. METHODS: Seventeen elderly patients (aged 70 years or more) and 113 younger patients who underwent LADG for early gastric cancer between May 1998 and July 2004, at the department of Surgery, Dong-A University Medical Center, were studied. Postoperative outcomes were compared. RESULTS: In elderly patients, co-morbidity was more common than in younger ones (P=0.0220) and postoperative complication rate was more common, too (P=0.0480). Operation time (P=0.7301), time to first flatus (P=0.4766), postoperative hospital stay (P=0.4860), mortality (P=0.2453), were similar in these two groups. CONCLUSION: Because LADG with systemic lymphadenectomy in elderly patients has more co-morbidity and complications than younger ones, great cares should be given to treat co-morbidity preoperatively and prevent complications during operation and postoperative period in elderly patients.

Mondor's Disease of the Breast: Clinical Manifestations and Imaging Findings

Mondor's disease or thrombophlebitis of the superficial veins of the breast is a rare benign condition and a self-limiting disease. The combination of the clinical manifestations and the imaging (mammographic & sonographic) findings is the typical sign of Mondor's disease of the breast. Therefore, an understanding of such an entity and knowledge of the clinical and imaging findings will make it possible to avoid the unnecessary biopsy or surgery. We report the case of a 53-year-old woman diagnosing as Mondor's diasease, who underwent evaluation of a tender, papable cord- like mass in her left breast associated with discoloration of the overlying skin.

Sulindac-induced Apoptosis without Oligonucleosomal DNA Fragmentation in HT-29 Cells: Its Special References to Mitochondrial Pathway

PURPOSE: This study was undertaken to reveal the molecular mechanism underlying sulindac-induced apoptosis in the human colon cancer cell line HT-29 (mutant p53). METHODS: Apoptosis was determined by using Hoechst 33342 staining, and translocation of proteins was established by using immunofluorescence, immunoelectron microscopy, and Western blotting after ultra- fractionation. RESULTS: This type of apoptosis was associated with decreased mitochondrial membrane potential, a translocation of the apoptosis-inducing factor (AIF) to the nucleus, and morphological evidence of nuclear condensation. However, DNA electrophoresis did not elucidate the ladder pattern of DNA fragments. Instead, a pulse-field gel electrophoresis showed that sulindac led to disintegration of nuclear DNA into-high- molecular-weight DNA fragments of about 100~300 kbp. CONCLUSIONS: Our findings indicate that sulindac induces large-scale DNA fragmentation, suggesting a predominantly AIF-mediated cell-death process, through translocation of the AIF to the nucleus in HT-29 cells.

Gene Expression Profiling of Breast Cancers with Emphasis of beta-Catenin Regulation

To gain molecular understanding of carcinogenesis of breast cancer, gene expression profiles were analyzed using cDNA microarray representing 4,600 cDNAs in 10 breast cancer samples and the adjacent noncancerous breast tissues from the same patients. The alterations in gene expression levels were confirmed by reversetranscription PCR in four randomly selected genes. Genes that were differently expressed in cancer and noncancerous tissues were identified. 106 (of which 55 were known) and 49 (of which 28 were known) genes were up- or down-regulated, respectively, in greater than 60% of the breast cancer samples. In cancer tissues, genes related to cell cycle, transcription, metabolism, cell structure/motility and signal transduction were mostly up-regulated. Furthermore, three cancer tissues showing immunohistochemically aberrant accumulation of beta-catenin in the nucleus and/or cytoplasm revealed down-regulation of Siah and Axin genes and up-regulation of Wnt and c-myc genes. These findings were highly consistent with Wnt signaling pathway associated with beta-catenin regulation previously suggested by others. Our studies, therefore, provide not only a molecular basis to understand biological processes of breast cancer but also useful resources to define the mechanism of beta-catenin expression in tumorigenesis of breast cancer.