Uhi Toh

Optimum Treatment Strategy for Superficial Esophageal Cancer: Endoscopic Mucosal Resection versus Radical Esophagectomy

This study was designed to determine the optimum treatment for a superficial esophageal cancer involving the mucosal or submucosal layer of the esophagus. The subjects were 150 patients with a superficial esophageal cancer who underwent endoscopic mucosal resection (EMR) or esophagectomy in Kurume University Hospital from 1981 to 1997. The mortality and morbidity rates, survival rate, and recurrence rate were retrospectively compared for (1) 35 patients who underwent EMR and 37 patients who underwent esophagectomy for a mucosal esophageal cancer and (2) 45 patients who underwent extended radical esophagectomy and 33 patients who underwent less radical esophagectomy for a submucosal esophageal cancer. Among the 72 patients with a mucosal cancer, lymph node metastasis/recurrence was observed in only one (1%); whereas of 78 patients with a submucosal cancer it was observed in 30 (38%). Among patients with a mucosal cancer the mortality and morbidity rates after EMR were lower than for those after esophagectomy. The survival rate after EMR was the same as that after esophagectomy. No recurrence was observed after either treatment modality. Among the patients with a submucosal cancer, the survival rate was higher and the recurrence rate lower after extended radical esophagectomy; than after less radical esophagectomy; the mortality and morbidity rates after extended radical esophagectomy were the same as those after less radical esophagectomy. Multivariate analysis demonstrated that the treatment modality (EMR versus esophagectomy) did not influence the survival of patients with a mucosal esophageal cancer, whereas it strongly influenced the survival of patients with a submucosal esophageal cancer. We concluded that EMR was the mainstay of treatment for a mucosal esophageal cancer, and extended radical esophagectomy was the mainstay of treatment for a submucosal esophageal cancer.

Optimal Lymphadenectomy for Squamous Cell Carcinoma in the Thoracic Esophagus: Comparing the Short- and Long-term Outcome among the Four Types of Lymphadenectomy

Controversy continues over the optimal extent of lymphadenectomy (regional versus three-field) for a potentially resectable squamous cell carcinoma in the thoracic esophagus. In the Consensus Conference of the International Society for Diseases of the Esophagus (ISDE), held in Munich in 1994, the types of lymphadenectomy were classified as standard, extended, total, or three-field lymphadenectomy. The objective of the present study was to determine the optimal procedure among these four types of lymphadenectomy. The mortality and morbidity rates, postoperative course, and survival rates were compared among 302 patients who underwent curative (R0) transthoracic esophagectomy with one of these four types of lymphadenectomy at Kurume University Hospital, Fukuoka, Japan, from 1986 to 1998. Three-field lymphadenectomy resulted in better survival than any other type of lymphadenectomy for patients with positive lymph node metastasis from a cancer in the upper or middle thoracic esophagus. A postoperative complication, such as recurrent laryngeal nerve paralysis, anastomotic leakage, and tracheal ischemic lesion, was significantly more common after three-field lymphadenectomy. However, the mortality rate was the same among the four procedures. Three-field lymphadenectomy was optimal for an upper or middle thoracic esophageal cancer with metastasis in the lymph node(s) based on improved long-term survival, whereas there was not a large difference in short-term and long-term outcomes after the four types of lymphadenectomy for a lower thoracic esophageal cancer.

Assessment of immunological biomarkers in patients with advanced cancer treated by personalized peptide vaccination

To investigate immunological biomarkers to predict overall survival of advanced cancer patients under treatment with personalized peptide vaccination, correlations between overall survival and biomarkers, including cytotoxic T lymphocyte (CTL) and immunoglobulin G (IgG) responses to the vaccinated peptides, were investigated in 500 advanced cancer patients who received personalized peptide vaccination from October 2000 to October 2008. The best clinical response was assessed for in 436 patients, 43 patients (10%) had partial response, 144 patients (33%) had stable disease and 249 patients (57%) had progressive, with a median overall survival of 9.9 months. Both lymphocyte counts prior to the vaccination (P = 0.0095) and increased IgG response (P = 0.0116) to the vaccinated peptides, along with performance status (P < 0.0001), well correlated with overall survival. To confirm the superiority of IgG response to CTL response, the samples from advanced castration-resistant prostate cancer patients who survived more than 900 days (n=20) and those who died within 300 days (n=23) were analyzed further. As a result, both the numbers of peptides, to which increased IgG responses were observed, and the fold increases in IgG levels were significantly higher in long-term survivors (P = 0.000282 and P = 0.00045). In contrast, CTL responses were not statistically different between the two groups. Both lymphocyte numbers and IgG response were thus suggested to be biomarkers of cancer vaccine for advanced cancer patients.

Bortezomib sensitizes human esophageal squamous cell carcinoma cells to TRAIL-mediated apoptosis via activation of both extrinsic and intrinsic apoptosis pathways

Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive human cancers, and novel treatment modalities are required. We investigated the therapeutic potential of the tumor necrosis factor–related apoptosis-inducing ligand (TRAIL/Apo2L) in combination with the proteasome inhibitor bortezomib (Velcade) on human ESCC cell lines. Bortezomib enhanced the susceptibility to TRAIL in 12 of the 15 ESCC cell lines tested, although most showed low sensitivity to TRAIL as a single agent. The enhancement of TRAIL-induced apoptosis by bortezomib was caspase dependent. Increased processing of caspase-8 often accompanied enhancement of TRAIL-induced apoptosis by bortezomib. However, the increased cell surface expression of death receptors observed on bortezomib treatment did not seem to be crucial for this effect. For some ESCC, bortezomib treatment resulted in a more efficient recruitment of caspase-8 and the Fas-associated death domain to the death-inducing signaling complex. Additional downregulation of the cellular FLICE-inhibitory protein long isoform [c-FLIP(L)] could cooperate in the activation of the extrinsic pathway in some cases. For other ESCC, the crucial effect of bortezomib treatment seemed to be increased signaling via the intrinsic apoptotic pathway on subsequent exposure to TRAIL. Thus, bortezomib could sensitize ESCC to TRAIL apoptosis by multiple molecular mechanisms of action. Therefore, the combination of bortezomib and TRAIL might be a novel therapeutic strategy for ESCC patients who fail to respond to standard chemoradiotherapy that predominantly targets the mitochondrial apoptotic pathway. Mol Cancer Ther; 9(6); 1842–51. ©2010 AACR.

FOXP3 expression in tumor cells and tumor-infiltrating lymphocytes is associated with breast cancer prognosis

The forkhead box protein 3 (FOXP3) transcription factor is highly expressed in tumor cells as well as in regulatory T cells (Tregs). It plays a tumor-enhancing role in Tregs and suppresses carcinogenesis as a potent repressor of several oncogenes. The clinical prognostic value of FOXP3 expression has not yet been elucidated. In this study, immunohistochemistry was used to investigate the prognostic significance of FOXP3 expression in tumor cells and tumor-infiltrating lymphocytes (TILs) in breast cancer patients. Of the 100 tumor specimens obtained from primary invasive breast carcinoma, 63 and 57% were evaluated as FOXP3+ tumor cells and as being highly infiltrated by FOXP3+ lymphocytes, respectively. Although FOXP3 expression in tumor cells was of no prognostic significance, FOXP3+ lymphocytes were significantly associated with poor overall survival (OS) (n=98, log-rank test P=0.008). FOXP3 exhibited a heterogeneous subcellular localization in tumor cells (cytoplasm, 31%; nucleus, 26%; both, 6%) and, although cytoplasmic FOXP3 was associated with poor OS (P= 0.058), nuclear FOXP3 demonstrated a significant association with improved OS (P=0.016). Furthermore, when patients were grouped according to their expression of tumor cytoplasmic FOXP3 and lymphocyte FOXP3, there were notable differences in the Kaplan-Meier curves for OS (P<0.001), with a high infiltration of FOXP3+ lymphocytes accompanied by a cytoplasmic FOXP3+ tumor being the most detrimental phenotype. These findings indicated that FOXP3 expression in lymphocytes as well as in tumor cells may be a prognostic marker for breast cancer. FOXP3 in tumor cells may have distinct biological activities and prognostic values according to its localization, which may help establish appropriate cancer treatments.

Preclinical and Clinical Studies of Novel Breast Cancer Drugs Targeting Molecules Involved in Protein Kinase C Signaling, the Putative Metastasis-Suppressor Gene Cap43 and the Y-box Binding Protein-1

Breast cancer is a common cause of tumors in women. The development of effective adjuvant therapies using drugs such as anthracyclines, taxanes, and aromatase inhibitors has improved the survival of breast cancer patients. Molecular cancer therapeutics are also attracting attention, and targeted molecular therapies, such as trastuzumab, have already contributed to effective new treatments for breast cancer. Other candidate targeted molecular therapies for breast cancer, including erlotinib, gefitinib, lapatinib, bevacizumab, and celecoxib, are currently undergoing clinical evaluation, and promising results are expected. The current review provides an up-to-date summary of the preclinical and clinical development of these drugs for breast cancer. In particular, we focus on therapies targeting protein kinase C (PKC) signaling, the putative metastasis-suppressor gene Cap43/N-myc downstream-regulated gene 1 (NDRG1)/differentiation-related gene-1 (Drg-1), and the Y-box binding protein-1 (YB-1). The PKC signaling pathway is widely considered to be a promising target for the development of novel therapeutics. Cap43 expression is significantly modulated by estrogen and/or anti-estrogens in breast cancer cells that are positive for estrogen receptor-alpha (ER-alpha). Cap43 is therefore of particular interest as a molecular indicator of the therapeutic efficacy of anti-estrogenic agents in breast cancer. The nuclear expression of YB-1 plays an essential role in the acquisition of malignant characteristics by breast cancer cells, through epidermal growth factor receptor 2 (HER2)-Akt-dependent pathways. Basic research investigating the key selective molecular changes that sustain breast cancer growth and progression, as demonstrated for PKC, Cap43, and YB-1, is allowing the development of specific targeted molecular diagnostics and therapeutics.

The relationship between 18F-FDG metabolic volumetric parameters and clinicopathological factors of breast cancer.

ObjectivesThis study was conducted to evaluate the relationship between fluorine-18 fluorodeoxyglucose metabolic parameters [maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG)] and clinicopathological factors of breast cancer. MethodsThe study comprised 93 patients. A volumetric region of interest was drawn over the abnormal focal uptake of breast cancer. Spearman’s rank correlation, the Kruskal–Wallis test, and receiver operating characteristic analysis were used to investigate the relationship between clinicopathological factors and metabolic parameters and determine which metabolic parameters were most highly associated with clinicopathological factors. ResultsAll parameters had a statistically significant relationship with pathological T stage (p-T stage), pathological N status (p-N status), pathological stage (p-stage), and triple-negative type (TN) (all P values were <0.05). There were statistically significant differences between SUVmax and TLG in relation to lymphatic invasion, estrogen receptor, and nuclear grade (P<0.05). High MTV showed a tendency toward association with estrogen receptor negativity, but the relation did not reach the level of statistical significance (P=0.056). No statistically significant relationship was observed between MTV and lymphatic invasion or nuclear grade. In the receiver operating characteristic analysis of p-T stage and p-stage, the AUC for TLG was significantly larger than that for SUVmax (P=0.0003 and 0.048, respectively). There were marginally significant differences between TLG and MTV in relation to p-stage (P=0.058). ConclusionTLG may reflect tumor metabolism for clinicopathological factors of breast cancer better than SUVmax or MTV.

Preclinical studies of molecular-targeting diagnostic and therapeutic strategies against breast cancer

We have investigated protein kinase C (PKC) signaling, a putative differentiation-related and metastasis suppressor gene Cap43/NDRG1/Drg-1, and Y-box binding protein-1 (YB-1) to identify new molecular targeting for breast cancer. PKC is a family of serine/threonine kinases that is involved in the regulation of cell growth. We have demonstrated that PKC caused G1 arrest in a breast cancer cell line through a mechanism involving a PKC–ERK MAPK–JNK–Rb protein signaling pathway. We have also characterized a novel mechanism through which all-trans retinoic acid (ATRA) and antineoplaston, anticancer drug, caused cell growth inhibition in breast cancer cells through effects on intracellular pathways. ATRA decreased the expression of PKCα, as well as reduced ERK MAPK phosphorylation, and consequently caused G1 arrest. Antineoplaston caused the down-regulation of PKCα protein expression, resulting in inhibition of ERK MAPK phosphorylation, with resultant inhibition of Rb phosphorylation leading to G1 arrest. PKC signaling represents a promising target for development of novel therapeutic agents. Cap43 is known as N-myc downstream-regulated gene 1 (NDRG1). Treatment with estradiol (E2) significantly decreased the expression of Cap43 in ER-α-positive breast cancer cell lines. Co-administration of tamoxifen abrogated the E2-induced downregulation of Cap43 in ER-α-positive cell lines. These results suggested that Cap43 may hold the potential of being a molecular marker to determine the therapeutic efficacy of anti-estrogenic anticancer agents in breast cancer. YB-1 is a member of the cold shock domain protein family. The expression of nuclear YB-1 was correlated with HER2 positively in clinical specimens of human breast cancer. Immunostaining studies showed that nuclear YB-1 expression was an independent prognostic factor of overall survival. Expression of nuclear YB-1 played an essential role in acquirement of malignant characteristics through HER2-dependent pathways in breast cancer patients. PKC, Cap43 and YB-1 may be useful in new molecular-targeting diagnosis and therapeutics in breast cancer.

Tricin inhibits proliferation of human hepatic stellate cells in vitro by blocking tyrosine phosphorylation of PDGF receptor and its signaling pathways

4′,5,7‐Trihydroxy‐3′,5′‐dimethoxyflavone (Tricin), a naturally occurring flavone, has anti‐inflammatory potential and exhibits diverse biological activities including antigrowth activity in several human cancer cell lines and cancer chemopreventive effects in the gastrointestinal tract of mice. The present study aimed to investigate the biological actions of tricin on hepatic stellate cells (HSCs) in vitro, exploring its potential as a treatment of liver fibrosis, since HSC proliferation is closely related to the progression of hepatic fibrogenesis in chronic liver diseases leading to irreversible liver cirrhosis and hepatocellular carcinoma. Tricin inhibited platelet‐derived growth factor (PDGF)‐BB‐induced cell proliferation by blocking cell cycle progression and cell migration in the human HSC line LI90 and culture‐activated HSCs. It also reduced the phosphorylation of PDGF receptor β and the downstream signaling molecules ERK1/2 and Akt, which might be due to its tyrosine kinase inhibitor properties rather than inhibition of the direct binding between PDGF‐BB and its receptor. Our findings suggest that tricin might be beneficial in HSC‐targeting therapeutic or chemopreventive applications for hepatic fibrosis. J. Cell. Biochem. 113: 2346–2355, 2012.

Adjuvant Chemotherapy after Radical Resection of Squamous Cell Carcinoma in the Thoracic Esophagus: Who Benefits?

Background: A definitive combined modality therapy superior to surgery alone has not yet been found for esophageal cancer. This retrospective study investigated the impact of postoperative adjuvant chemotherapy in patients who underwent curative (R0) esophagectomy with radical lymphadenectomy. Study Design: Two hundred and eleven patients with a squamous cell carcinoma in the thoracic esophagus who underwent transthoracic curative (R0) esophagectomy with radical lymphadenectomy, such as 3-field lymphadenectomy or total 2-field lymphadenectomy, between 1988 and 2000, were retrospectively reviewed. Ninety-four patients received postoperative chemotherapy – 2 courses of cisplatin (CDDP) plus fluorouracil (5-FU) or vindesine (VDS) – while the other 117 patients received surgery alone. The overall survival rate was compared between the two groups after being stratified by the numbers of the metastasis- positive lymph nodes. Results: Only in the subgroup of patients with 8 or more lymph nodes metastasis- positive, the surgery-with-postoperative-chemotherapy group had a significantly better survival than the surgery-alone group. No significant difference was found in survival between the two groups in any other stratified subgroup. Conclusions: Postoperative adjuvant chemotherapy following curative (R0) esophagectomy with radical lymphadenectomy such as 3-field lymphadenectomy or total 2-field lymphadenectomy provided a benefit only in patients having metastasis in a large number – 8 or more – lymph nodes.