Evaluation of TS-1 based treatment and expression of thymidylate synthase and dihydropyrimidine dehydrogenase on oral squamous cell carcinoma

S-1 salvage chemotherapy for stage IV thymic carcinoma: a study of 44 cases

Background

Thymic carcinoma (TC) is a rare mediastinal tumor, and patients with stage IV TC have a poor prognosis. No optimal chemotherapeutic regimen has yet been established. In this study, we evaluated the efficacy and safety of S-1 as a salvage mono-therapy in stage IV TC.

Methods

Patients with histologically confirmed stage IV TC were enrolled in this study when front-lined chemotherapy failed. S-1 capsules were orally taken twice a day. The daily dose was prescribed in three levels (80, 100, 120 mg) based on body surface area (BSA). One cycle of treatment consists of 4 weeks of drug use and 2 weeks of rest. The cycle was repeated until tumor progressed or intolerable toxicity occurred. The response rate, progression-free survival (PFS), overall survival (OS), and toxicity were evaluated.

Results

Forty-four patients with stage IV TC were included between January 2013 and July 2017. Squamous cell carcinoma accounted for 84% of cases (37/44). There were 22 males and 22 females with a median age of 57 years (27-78 years). S-1 was prescribed at a dose of 80 mg for 18 (41%) patients, 100 mg for 17 patients (38%), and 120 mg for 9 patients (21%). The median number of cycles of administrated per patient was 3 [1-32]. Among 44 patients, 13 (30%) achieved a partial response, 22 (50%) remained stable disease, and 9 (20%) showed a rapid progression. With a median follow-up time of 14 months, the median PFS and OS of the whole group were 6 (95% CI, 7.0-13.9) months and 15 (95% CI, 13.2-21.6) months, respectively. For the 13 patients who showed response to S-1, the median PFS was 22 (95% CI, 15.5-30) months. Anorexia was the most common side effect, but all cases were mild. Other toxicities of grade ≥3 were bone marrow suppression (n=6) and rash (n=1). No drug-related deaths occurred.

Conclusions

S-1 is a safe and effective treatment for stage IV TC as a salvage monotherapy. It is especially effective in disease control when the tumor shows response to S-1.

Lung metastasis from perineal leiomyosarcoma: a case report and a review of the Japanese literature

Pulmonary metastasis from leiomyosarcoma is rare and its clinical management is challenging. A single lung metastasis from a perineal leiomyosarcoma occurred in a 79-year-old woman. Five months after resection of the lung metastasis, a new metastatic tumor developed in the contralateral lung. Since the patient did not desire to receive hospitalized treatment, TS-1 (an oral agent consisting of a combination of tegafur, gimeracil, and oteracil potassium) therapy was started on an outpatient basis. The lung metastasis has been successfully controlled for at least 17 months with excellent tolerability. The clinical features and the treatment of this case are discussed.

Messenger RNA and protein expression of thymidylate synthase and DNA repair genes in thymic tumors

BACKGROUND

Thymic epithelial tumors include several entities with different biologic behavior. Chemotherapy is indicated in advanced disease, but limited data exist on gene expression correlation with the response to chemotherapeutic agents.

PATIENTS AND METHODS

A series of 69 thymic neoplasms (7 A-, 6 AB-, 6 B1-, 10 B2-, 14 B3-thymomas, 22 carcinomas and 4 combined tumors) was collected to assess gene expression of thymidylate synthase (TS), excision repair cross complementing-1 (ERCC1), ribonucleotide reductase subunit 1 (RRM1), topoisomerase 2α (TOP2A) and mTOR.

RESULTS

A strong linear correlation between TS gene and protein expression was observed (P<0.0001, R=0.40). TS expression was significantly lower in pure A-thymomas and thymic carcinomas (P<0.0001) and progressively decreasing from B1-type to thymic carcinomas (B1>B2>B3>C; P<0.0001). RRM1 and TOP2A mRNA expression levels were significantly correlated with TS levels (both P=0.03) with a similar trend of expression among histotypes. RRM1 and TOP2A high levels were significantly correlated with high TS (P=0.03) and low tumor stages (I-II) (P<0.0001 and P<0.01, respectively). No relevant changes of ERCC1 and mTOR were detected.

CONCLUSIONS

Low TS and, to a minor extent, RRM1 and TOP2A expression were detected in aggressive thymic tumors. These findings should be prospectively considered in selecting the most appropriate chemotherapy.

Expression of thymidylate synthase and orotate phosphoribosyltransferase in thymic carcinoma

Thymic carcinoma is a rare thymic epithelial tumor in which chemotherapy for advanced disease has not yet been established. Thymidylate synthase (TS) and orotate phosphoribosyltransferase (OPRT) protein expression levels in thymic carcinoma were evaluated as possible indicators of the anticancer activity of 5-fluorouracil (5-FU) drugs using immunohistochemistry (IHC). A total of 24 samples of thymic carcinoma were used in the present study. The tumor sections were immunohistochemically stained for TS and OPRT. As a comparison with thymic carcinoma, we also assessed the TS and OPRT protein expression levels in 55 lung cancer samples. The TS expression was positive in 12 of 24 thymic carcinoma samples (50%) and OPRT expression was positive in 10 (42%). The association between TS and OPRT expression and Masaoka stages of thymic carcinoma was analyzed. The TS and OPRT expressions in stage IV were significantly higher compared to that in stages I, II or III. We also compared the TS and OPRT expression levels between thymic carcinoma and lung cancer (33 adenocarcinomas and 22 squamous cell carcinomas). TS expression in thymic carcinoma was significantly lower compared with lung squamous cell carcinoma. OPRT expression in thymic carcinoma was significantly higher compared to lung adenocarcinoma. The combination of a relatively low expression of TS and high expression of OPRT suggests an improved antitumor effect of 5-FU drugs in thymic carcinoma compared to in lung carcinoma.

Role of thymidylate synthase and dihydropyrimidine dehydrogenase mRNA expressions in gallbladder carcinoma

PURPOSE

Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) are important enzymes in the metabolism of 5-fluorouracil, which have been examined as possible predictive markers. We conducted this study to clarify the role of TS and DPD expressions in gallbladder carcinoma (GBC).

METHODS

The subjects were 28 patients who underwent surgical resection of GBC. We examined intratumoral TS and DPD mRNA expressions, using the Danenberg tumor profile method. The expression levels were classified into two groups, based on median values. Clinicopathological variables, including prognosis, were then compared between the high and low expression groups.

RESULTS

There was a significant difference in the incidence of lymph node metastasis between the high and low TS expression groups. The incidence of advanced clinical stage was higher in the low TS expression group than in the high TS expression group. However, no clear correlation was observed between the DPD mRNA expression and any clinicopathological variable. There was no significant difference in the postoperative survival rates between the groups, in accordance with the expression of TS or DPD genes.

CONCLUSION

Low TS mRNA was correlated with a high incidence of lymph node metastasis and advanced clinical stage. Therefore, TS gene expression may help identify patients at increased risk of the progression of GBC.

Role of dihydropyrimidine dehydrogenase and thymidylate synthase expression in immunohistochemistry of intrahepatic cholangiocarcinoma

AIMS

  Dihydropyrimidine dehydrogenase (DPD) and thymidylate synthase (TS) are key enzymes in the metabolism of 5-fluorouracil and have been implicated as possible prognostic markers for cancer patients. However, the clinical roles of DPD and TS in intrahepatic cholangiocarcinoma (IHCC) have not been investigated. The aim of this study was to clarify the clinicopathological role of DPD and TS expressions in IHCC.

METHODS

  Twenty-nine patients who had undergone hepatic resection for IHCC were enrolled in this study. Expressions of DPD and TS in the resected IHCC specimens were examined using anti-DPD or anti-TS antibody. The patients were divided into positive and negative groups according to DPD/TS expressions: DPD-positive group (n = 18) and DPD-negative group (n = 11)/TS-positive group (n = 14) and TS-negative group (n = 15). Clinicopathological factors were compared between the two groups.

RESULTS

  The overall survival rate was significantly lower in the DPD-negative group than in the DPD-positive group (1-year 36.4% vs. 77.4%, 3-year 18.2% vs. 43.0%; P < 0.05). The disease-free survival rate in the DPD-negative group tended to be lower than that in the DPD-positive group. The overall survival rate or disease-free survival rate did not appear to be associated with the TS-expression status. The Ki-67 labeling index in the DPD-negative group was significantly higher than that in the DPD-positive group (16.9 ± 3.2% vs.13.2 ± 3.3%; P < 0.05).

CONCLUSIONS

  The negative DPD expression was significantly associated with the enhanced tumor cell proliferation and poorer prognosis in patients with IHCC. DPD expression is a potential prognostic indicator for IHCC.

The therapeutic efficacy of S-1 against orthotopically implanted human pleural mesothelioma cells in severe combined immunodeficient mice

Purpose

Malignant pleural mesothelioma (MPM) is a highly lethal neoplasm. S-1 has been developed as a novel oral antineoplastic agent based on the modulation of 5-fluorouracil (5-FU) bioactivity. This study was conducted to investigate the preclinical therapeutic effect of S-1 on MPM.

Methods

We used three human MPM cell lines, Y-MESO-14, NCI-H290 and MSTO-211H. In vitro proliferation of human MPM cells was determined by MTT assay. Human MPM cells were orthotopically implanted into thoracic cavity of SCID mice. Tumor-bearing mice were treated with S-1 or vehicle.

Results

The combination of 5-FU and 5-chloro-2,4-dihydroxypyridine (CDHP) was more effective than 5-FU alone in inhibiting MPM cell proliferation in vitro. This combination was most effective in Y-MESO-14 cells, which co-expressed high protein level of dihydropyrimidine dehydrogenase (DPD) and thymidine phosphorylase (TP). In vivo data showed that treatment with S-1 significantly reduced thoracic tumors and pleural effusion produced by Y-MESO-14 cells. Moreover, treatment with S-1 prolonged the survival of Y-MESO-14 cell-bearing SCID mice.

Conclusions

We demonstrated that S-1 was effective for inhibiting the proliferation of MPM cells, particularly with both DPD and TP expressions, suggesting that S-1 might be therapeutically effective for control of MPM.

Clinical relevance of thymidylate synthase (TS) activity for S-1-based chemotherapy in squamous cell carcinoma of the oral cavity

S-1 is a newly developed oral fluoropyrimidine derivative that is now widely used as a chemotherapeutic agent in the treatment of oral squamous cell carcinoma (SCC). Thymidylate synthase (TS) is the rate-limiting enzyme in the de novo DNA biosynthetic pathway, and improves clinical response to chemotherapy with fluoropyrimidines. We have retrospectively evaluated the predictive value of thymidylate synthase activity in 75 patients with oral SCC with an enzyme-linked immunosorbent assay (ELISA). Mean (SD) activity (pmol/mg) in the specimens was 0.078 (0.080) (median 0.059). The median value was taken as the cut-off value based on which the patients were divided into high and low activity groups. Both the clinical and histopathological responses to chemotherapy and radiochemotherapy were higher in the group with low TS activity. The group with low TS activity also differed significantly in their clinical response to S-1-based chemotherapy (p<0.05). However, there was no significant difference in cause-specific survival. Measurement of TS activity may aid in predicting the clinical response to chemotherapy including S-1 for oral SCC.

Thymidylate synthase, thymidine phosphorylase and orotate phosphoribosyl transferase levels as predictive factors of chemotherapy in oral squamous cell carcinoma

We conducted a clinicopathologic study on protein and mRNA levels of thymidylate synthase (TS), thymidine phosphorylase (TP) and orotate phosphoribosyl transferase (OPRT) using biopsy tissue specimens before treatment. The mRNA levels have been measured in tumor cells microdissected from paraffin-embedded specimens (Danenberg Tumor Profile method: DTP method). We studied the mRNA and protein expression as effect predictive factors in chemotherapy. The subjects consisted of 20 cases of untreated oral squamous cell carcinoma who had undergone chemotherapy with TS-1 (16 males and 4 females, tongue in 8 cases, upper gingiva in 3 cases, lower gingiva in 3 cases, buccal mucosa in 5 cases and floor of the mouth in 1 case). TS gene expressions of the responders were lower than those for the nonresponders. Furthermore, regarding males who were less than 70 years of age, stage I and II, well differentiated type and tongue, TS mRNA expression of the responders were lower than that for the nonresponders. The mRNA expression of OPRT for the male responders was lower than that for the nonresponders. No remarkable difference was observed by immunohistochemistry. In this study, the measurement of the TS levels using the DTP method may potentially act as a predictive factor of antitumor effectiveness.