Ching-Hung Lin

Comparison of the expression and prognostic significance of differentiation markers between diffuse large B-cell lymphoma of central nervous system origin and peripheral nodal origin.

PURPOSE: Whether diffuse large B-cell lymphoma (DLBCL) of primary central nervous system origin (PCNSL) is biologically different from DLBCL of peripheral nodal origin (NL) remains unclear. The purpose of this study was to compare the expression frequencies and prognostic significance of a panel of cell differentiation markers between these two disease entities. EXPERIMENTAL DESIGN: This study included HIV-unrelated patients with PCNSL (n = 51) and NL (n = 72) treated at four hospitals in Taiwan for whom archival tumor tissue was available. Immunohistochemistry for CD10, BCL-6, MUM-1, vs38c, CD138, and BCL-2 was done. CD10, BCL-6, and MUM-1 expression results were used to classify all cases into the germinal center B-cell (GCB) or the non-GCB subgroup. The prognostic significances of clinical and immunophenotypic markers were evaluated. RESULTS: Nuclear MUM-1 expression was significantly higher in PCNSL than in NL (P < 0.001; 84% versus 53%). PCNSL tumors were more frequently classified into the non-GCB subgroup than NL tumors (P = 0.020; 78% versus 62%). For patients with PCNSL, univariate analysis showed that patients with BCL-6 expression had a trend towards longer survival (P = 0.073; median survival, 25.3 versus 7.3 months), and multivariate analysis showed BCL-6 was an independent prognostic factor (P = 0.026). For patients with NL, both of univariate (P = 0.003) and multivariate analyses (P = 0.002) showed that GCB was significantly associated with favorable survival. CONCLUSION: The higher frequency of non-GCB subclassification, which was mainly contributed by nuclear MUM-1 expression in PCNSL implies that it has a more differentiated cellular origin than NL. BCL-6 expression in patients with PCNSL and GCB subgroup in patients with NL were favorable prognostic factors.

Epigenetic influences of low-dose bisphenol A in primary human breast epithelial cells

Substantial evidence indicates that exposure to bisphenol A (BPA) during early development may increase breast cancer risk later in life. The changes may persist into puberty and adulthood, suggesting an epigenetic process being imposed in differentiated breast epithelial cells. The molecular mechanisms by which early memory of BPA exposure is imprinted in breast progenitor cells and then passed onto their epithelial progeny are not well understood. The aim of this study was to examine epigenetic changes in breast epithelial cells treated with low-dose BPA. We also investigated the effect of BPA on the ERα signaling pathway and global gene expression profiles. Compared to control cells, nuclear internalization of ERα was observed in epithelial cells preexposed to BPA. We identified 170 genes with similar expression changes in response to BPA. Functional analysis confirms that gene suppression was mediated in part through an ERα-dependent pathway. As a result of exposure to BPA or other estrogen-like chemicals, the expression of lysosomal-associated membrane protein 3 (LAMP3) became epigenetically silenced in breast epithelial cells. Furthermore, increased DNA methylation in the LAMP3 CpG island was this repressive mark preferentially occurred in ERα-positive breast tumors. These results suggest that the in vitro system developed in our laboratory is a valuable tool for exposure studies of BPA and other xenoestrogens in human cells. Individual and geographical differences may contribute to altered patterns of gene expression and DNA methylation in susceptible loci. Combination of our exposure model with epigenetic analysis and other biochemical assays can give insight into the heritable effect of low-dose BPA in human cells.

The biomarkers of human papillomavirus infection in tonsillar squamous cell carcinoma—molecular basis and predicting favorable outcome

Presence of human papillomavirus (HPV) in variable proportions in tonsillar squamous cell carcinoma tissues has been demonstrated by several worldwide studies. Some reports emphasized the significance of HPV in predicting a better prognosis, as well as ethnic differences between Chinese and Caucasians. In order to understand the biological role of HPV and find out clinically accessible methods to determine its prognostic significance in primary tonsillar squamous cell carcinoma, we collected 92 patients with primary tonsillar squamous cell carcinoma diagnosed or treated in National Taiwan University Hospital, for whom archival tumor tissue were available. Immunohistochemical stains of p16INK4A, high-risk HPV in situ hybridization, and nested polymerase chain reaction (PCR)-based genechips were performed to detect HPV infection and determine its genotype. Clinical data were compared with HPV infection detected by the different methods mentioned above. Real-time PCR was also performed on the HPV16-positive [HPV16(+)] lesions to understand viral integration status. The positive rates of nested PCR-based genechips, overexpression of p16INK4A, and high-risk HPV in situ hybridization were 75% (69/92), 53% (49/92), and 44% (40/92), respectively. Both overexpression of P16INK4A and high-risk HPV in situ hybridization positivity were associated with favorable prognoses (P=0.004 and 0.001, respectively) and also independent prognostic factors in multivariate analyses (P=0.01 and 0.01, respectively). The positivity of nested PCR-based genechips was not statistically significant. From our data, primary tonsillar squamous cell carcinoma with positive immunohistochemical stains of p16INK4A and/or high-risk HPV in situ hybridization is associated with a better outcome, and both methods may serve as clinically accessible markers.

Molecular subtypes of breast cancer emerging in young women in Taiwan: evidence for more than just westernization as a reason for the disease in Asia.

Background: In the past two decades, the incidence of breast cancer in young Taiwanese females has been rapidly increasing, approaching the risk level of western countries. As a first step to investigate the possible etiology, we examined the molecular subtypes of female breast cancer in Taiwan. Methods: This study included 1,028 consecutive patients with breast cancer diagnosed in National Taiwan University Hospital between 2004 and 2006. Estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2, cytokeratin 5/6, and epidermal growth factor receptor expression and/or gene amplification were analyzed. Results: Younger (≤50 years) breast cancer patients had a higher prevalence of luminal A (67% versus 57%; P < 0.001) and a lower prevalence of basal-like subtype (9% versus 17%; P < 0.001) compared with older (>50 years) patients. The higher prevalence of luminal A subtype was mainly attributed to a higher ER (75% versus 63%; P < 0.001) and PR (47% versus 33%; P < 0.001) expression rate in younger patients than older patients. Tumors with histologic grade 3 were less prevalent in younger patients than in older patients (23% versus 30%; P = 0.01). For very young (<35 years) patients, the molecular subtype distribution, ER and/or PR expression rate, and histologic grade were not significantly different from those of less young (35-50 years) patients. Conclusions: Young breast cancer patients in Taiwan are characterized by a high prevalence of luminal A subtype and low prevalence of histologic grade 3 tumor and/or basal-like subtype. These features are distinct from young breast cancer patients in western countries. (Cancer Epidemiol Biomarkers Prev 2009;18(6):1807–14)

Unexpected rapid progression of metastatic adenoid cystic carcinoma during treatment with imatinib mesylate.

There is a lack of effective treatment for metastatic adenoid cystic carcinoma (ACC), a usually indolent tumor. We studied the efficacy of imatinib mesylate, a potent inhibitor of KIT tyrosine kinase, in patients with KIT‐positive metastatic ACC.

Distant metastasis in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) relapses more frequently than hormone receptor-positive subtypes and is often associated with poor outcomes. This retrospective study reviewed the pattern of distant metastasis with regard to survival in patients with TNBC. A total of 205 TNBC patients were analyzed. TNBC patients with lung metastases had the longest median post-metastatic OS (with 95% confidence interval) of 16.6 (10.3-22.9) months, followed by the bone, 16.3 (11.7-20.8) months, the liver, 8.9 (3.5-14.4) months, the pleura, 7.5 (2.8-12.3) months, and the brain, 4.3 (0.6-8.0) months. Kaplan-Meier plots indicated that TNBC patients with metastatic spread to brain, liver, and pleural had poorer post-metastatic OS rate than patients with lung metastases (p = 0.001, 0.004, and 0.029, respectively). Moreover, brain and liver metastases correlated significantly with poorer post-metastatic OS as compared to bone metastasis (p = 0.004 and 0.011, respectively). Route of first metastasis correlated significantly with survival of TNBC patients with brain metastases being the poorest survival indicator, followed by metastases to liver, pleura, bone, and lung.

Bevacizumab Preconditioning Followed by Etoposide and Cisplatin Is Highly Effective in Treating Brain Metastases of Breast Cancer Progressing from Whole-Brain Radiotherapy

Purpose: We hypothesized that a window period between bevacizumab and cytotoxic agents may enhance drug delivery into tumor tissue through bevacizumab-induced vascular normalization in patients with brain metastases of breast cancer (BMBC). Experimental Design: A single-arm phase II study was conducted in which BMBC patients refractory to whole-brain radiotherapy (WBRT) were enrolled. In a 21-day cycle, patients received bevacizumab (15 mg/kg) on day 1, which, with a 1-day window period, was followed by etoposide (70 mg/m2/day; days 2–4) and cisplatin (70 mg/m2; day 2; BEEP regimen). The BEEP regimen was administered for a maximum of 6 cycles. The primary endpoint was the central nervous system (CNS)–objective response rate according to volumetric response criteria. Results: A total of 35 patients were enrolled between January 2011 and January 2013. The median age was 54.3 years (range, 33–75); 19 patients (54.3%) had an Eastern Cooperative Oncology Group performance status of 2 or 3. Twenty-seven patients [77.1%; 95% confidence interval (CI), 59.9–89.6] achieved a CNS-objective response, including 13 patients (37.1%) with a ≥80% volumetric reduction of CNS lesions. With a median follow-up of 16.1 months, the median CNS progression-free survival and overall survival times were 7.3 months (95% CI, 6.5–8.1) and 10.5 months (95% CI, 7.8–13.2), respectively. Common grade 3 or 4 toxicities included neutropenia (30.8%) and infection (21.3%). Conclusions: By administering bevacizumab 1 day before etoposide and cisplatin, the BEEP regimen appeared highly effective in BMBC refractory to WBRT. Further study of vascular normalization window concept is warranted. Clin Cancer Res; 21(8); 1851–8. ©2015 AACR.

The emerging epidemic of estrogen-related cancers in young women in a developing Asian country.

The incidence of breast and genital tract cancers is increasing among Taiwanese women, but the age specificity and histopathological features of these cancers have not been determined. We used a descriptive epidemiological method and data from the Taiwan Cancer Registry (1979–2007) to examine secular trends in the age‐specific incidences of female breast cancer, three major female genital tract cancers and the histopathological subtypes of these cancers. Age‐specific incidence rates in the United States (1978–2002) were used as an external reference, and the incidence rates of all malignancies and of malignant brain tumors were used as internal references. We found that age‐adjusted incidence rates of female breast, uterine, and ovarian cancers increased in Taiwan from 1979 to 2007, whereas the incidence of cervical cancer decreased after 1998. The largest increase was observed for ductal and lobular carcinomas of the breast and endometrioid carcinomas of the uterus and ovary in women ≤55 years, all of these tumors show a high prevalence of hormone receptor expressions. In addition, hormone‐receptor‐positive rates of breast cancer were uniquely higher in younger, as opposed to older, Taiwanese women. These findings indicate that estrogen‐related cancers rapidly emerge in young women in Taiwan and that incidence rates are catching up with that of women living in the United States.

O6-Methylguanine-DNA methyltransferase expression and prognostic value in brain metastases of lung cancers

O(6)-Methylguanine-DNA methyltransferase (MGMT) is critical for repairing pro-mutagenic DNA bases and is correlated with response to alkylating agents in cancers. Since there is great interest in pursuing the potential role of temozolomide, a novel alkylating agent, in the treatment of brain metastases, this study aimed to evaluate MGMT expression as well as its prognostic value in this devastating disease. We studied the expression and methylation status of MGMT in 86 brain metastases of lung cancers. Twenty of them had matched primary lung tumor tissues available for direct comparison. MGMT expression was assessed by immunohistochemistry (IHC); the methylation status of MGMT promoter was analyzed by nested methylation-specific PCR (MSP) and validated by quantitative real-time PCR analysis. Positive nuclear MGMT expression was detected more frequently in brain metastases as compared with primary lung cancers (83% versus 50%, P=0.004). The discordance in MGMT expression persisted in the 20 paired primary and metastatic tumors (P=0.031). MGMT promoter hypermethylation was highly correlated with loss of MGMT expression. Both univariate and multivariate analyses showed that median overall survival was significantly longer in patients with positive MGMT expression in brain metastases (16.5 versus 3.5 months, P<0.001). In conclusion, MGMT expression was enhanced in brain metastases as compared with the primary lung cancers. MGMT expression in brain metastases was significantly correlated with better survival.

Unique features of breast cancer in Asian women—Breast cancer in Taiwan as an example

Breast carcinoma is one of the most common cancers in women and is known to arise from a multifactorial process, the effect of reproductive risk factors strongly supporting a hormonal role in its etiology. Breast cancer in Asia is characterized by a lower incidence than in Western populations, but is still the leading type of cancer in Asian women, and a significant increasing tread indicates that it is an issue of particular public health importance. Asian breast cancer is characterized by early tumor onset, showing a relatively younger median age at diagnosis. Recently, scientists began to explore the tumorigenic mechanisms underlying breast cancer formation at the molecular level. Both a candidate-gene approach and genome-wide association studies have yielded crucial insights into breast cancer susceptibility genes initiating breast tumorigenesis. As expected, ethnic/racial variation in the genotypic frequency of these genes results in differences in breast cancer incidence in different populations. Furthermore, the question of how important these genes are in Asian breast cancer remains to be explored. It has been demonstrated that gene expression profiles and gene sets are prognostic and predictive for patients with breast cancer. Originally, due to its early onset, it was speculated that Asian breast cancer would have a higher frequency of the basal-like subtype of breast cancer, a molecular subtype characterized by poor differentiation, resulting in a relatively poor progression; however, recent findings do not support this speculation. The frequency of the luminal-A subtype of breast cancer, characterized by estrogen receptor expression, is similar to that in breast cancer in Caucasian, supporting the usefulness of hormone-based therapy in Asian breast cancer.