Pathological responses to low-dose irradiation and Pepleomycin in Oral squamous cell carcinoma are predictive of Locoregional control.

BACKGROUND: The prognosis of advanced oral cancer remains dismal. While multimodal therapy is beneficial, maintaining the quality of life of long-term survivors is important. Therefore, risk-adapted treatment regimens need to be designed. We herein investigated whether pathological responses in oral cancer patients treated with preoperative chemoradiotherapy predict locoregional recurrence. METHODS: We retrospectively reviewed the data of 51 oral cancer patients who received preoperative radiotherapy and concurrent pepleomycin, followed by curative surgery at our institution between January 2009 and June 2018. Each patient received preoperative external beam irradiation to the primary tumor and lymphatics (2 Gy per day for approximately 3 weeks) concurrent with pepleomycin (2.5 mg/day). Surgery was performed approximately 3-4 weeks after the completion of preoperative chemoradiotherapy. Pathological responses were defined based on the grading system of Oboshi and Shimosato. RESULTS: Eight, 22, 16, and 5 patients had Oboshi and Shimosato grades 2a, 2b, 3, and 4, respectively. Favorable pathological responses (grades 3 and 4) were observed in 41.2% of patients (21 out of 51 patients). The pathological response and number of pathological lymph node metastases were identified as significant prognostic factors for locoregional control in the univariate analysis. Three-year locoregional control rates were 100 and 56.6% in patients with favorable and unfavorable pathological responses, respectively. CONCLUSIONS: The present study demonstrated that pathological tumor responses to preoperative chemoradiotherapy are a useful predictive factor for locoregional control.

Investigating Nucleosome Accessibility for MNase, FeII †Peplomycin, and Duocarmycin†B2 by Using Capillary Electrophoresis.

Capillary electrophoresis, coupled with DNA 5' Texas Red labeling, was used to investigate the ability of MNase, FeII peplomycin, and duocarmycin B2 to access the nucleosome. Distinct accessibility patterns of these species to the nucleosome were observed. MNase was completely prevented from approaching the nucleosome core and exhibited a higher site specificity for targeting DNA sites located close to the core region. Intercalation of peplomycin in the nucleosomal core region was highly suppressed, but reaction sites located at the ends of the nucleosomal core remained accessible, which implied flexibility of the core DNA end. Duocarmycin B2 was able to enter and react in the core region, although its alkylating efficiency decreased significantly.

Interaction of Zn(II)bleomycin-A2 and Zn(II)peplomycin with a DNA hairpin containing the 5'-GT-3' binding site in comparison with the 5'-GC-3' binding site studied by NMR spectroscopy.

Bleomycins are a group of glycopeptide antibiotics synthesized by Streptomyces verticillus that are widely used for the treatment of various neoplastic diseases. These antibiotics have the ability to chelate a metal center, mainly Fe(II), and cause site-specific DNA cleavage. Bleomycins are differentiated by their C-terminal regions. Although this antibiotic family is a successful course of treatment for some types of cancers, it is known to cause pulmonary fibrosis. Previous studies have identified that bleomycin-related pulmonary toxicity is linked to the C-terminal region of these drugs. This region has been shown to closely interact with DNA. We examined the binding of Zn(II)peplomycin and Zn(II)bleomycin-A2 to a DNA hairpin of sequence 5'-CCAGTATTTTTACTGG-3', containing the binding site 5'-GT-3', and compared the results with those obtained from our studies of the same MBLMs bound to a DNA hairpin containing the binding site 5'-GC-3'. We provide evidence that the DNA base sequence has a strong impact in the final structure of the drug-target complex.

Immunomodulatory effects of peplomycin on immunosuppressive and cytotoxic cells in the lesional skin of cutaneous squamous cell carcinoma.

BACKGROUND: Continuous intra-arterial administration of peplomycin (PEP) through a tumor-feeding artery using an intravascular indwelling catheter is one of the best treatments for cutaneous squamous cell carcinoma (SCC) on cosmetic areas. Although this reagent is useful for the treatment of SCC, its immunomodulatory effect on the tumor microenvironment is still unknown. OBJECTIVE/METHODS: In this study, we investigated the immunomodulatory effects of PEP on the tumor-infiltrating regulatory T cells and tumor-associated macrophages as well as CD8(+)TIA-1(+) cytotoxic T cells in the lesional skin of 5 patients with SCC on the lips. RESULTS: Our data suggest that, in addition to the direct antitumor effects, PEP decreased immunosuppressive cells and increased cytotoxic T lymphocytes at the tumor sites, which might maintain antitumor immune response against SCC.

Distribution study of peplomycin in rat kidney revealed by immunocytochemistry using monoclonal antibodies.

Peplomycin (PEP), an anti-tumor antibiotic related structurally to bleomycin, is widely used, especially for squamous cell carcinoma but shows renal toxicity. We prepared monoclonal antibodies (mAbs) against N-(γ-maleimidobutyryloxy)succinimide-conjugated PEP. The mAbs were monospecific for PEP, but did not react with bleomycin and other anticancer antibiotics. The mAbs enabled us to develop an immunocytochemical (ICC) method for detecting the uptake of PEP in the rat kidney. Two hours after a single i.v. administration of PEP, ICC revealed immunostaining for PEP in irregularly shaped cytoplasmic granules of the proximal tubules in which the microvilli were also stained. Also, staining occurred in the distal tubules and collecting ducts, in both of which we observed scattered swollen cells, reminiscent of necrotic cells, in which both the nuclei and cytoplasm reacted strongly with the antibody. Twenty-four hours after injection, PEP in the proximal tubules completely vanished, but yet significant amounts of PEP remained in both the distal tubules and collecting ducts. Distribution patterns of PEP in cells of the kidneys resembled, in some ways, those of our recent ICC studies for an organic cation aminoglycoside antibiotic gentamicin. This ICC suggests that PEP taken up in the proximal tubule cells is localized in the lysosomes, and organic cation transporters and bleomycin hydrolase might be involved in entrance and/or disappearance of PEP in this cell type. Furthermore, the distal tubules and collecting ducts may be the sites readily affected by some chemotherapeutic agents.

Preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil for oral squamous cell carcinoma.

The objectives of this study were to evaluate survival in 141 patients with stage II-IV oral squamous cell carcinoma (OSCC) treated with preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil (IADCPIVF) via the superficial temporal artery, and to clarify the prognostic factors. The study population included 59 patients with stage II OSCC, 34 with stage III, and 48 with stage IV. After IADCPIVF, 139 patients underwent surgery; minimally invasive surgeries (MIS) including excisional biopsy were performed on 96 patients with a remarkably good response to IADCPIVF. The primary tumour response rate was 99.3% (complete response rate 56.7%, good partial response rate 17.0%, fair partial response rate 25.5%). Additionally, there were no serious adverse events associated with IADCPIVF. The 5-year overall survival rate was 74.6% (stage II 83.6%, stage III 72.7%, stage IV 64.8%). In the multivariate analysis of survival, T classification and clinical tumour response were significant prognostic factors. Eight (8.3%) of the patients who received MIS had primary recurrence and six were salvaged. In conclusion, IADCPIVF is safe and efficacious for treating OSCC, and MIS could reduce the extent of primary tumour resection in the case of a remarkably good response.

Results of concomitant chemoradiation for cervical cancer using high dose rate intracavitary brachytherapy: study of JROSG (Japan Radiation Oncology Study Group).

The purpose of this study was to clarify outcome for concurrent chemoradiation (CT-RT) in locally advanced cervix cancer in Japan. This is a non-randomized retrospective analysis of 226 patients treated with definitive CT-RT or radiotherapy alone (RT alone) in nine institutions between 2001 and 2003. External irradiation consisted of whole pelvic irradiation and pelvic side wall boost irradiation, using a central shield during the latter half of the treatment with the anteroposterior parallel opposing technique. The external beam irradiation was performed with 1.8 or 2 Gy per fraction. High-dose-rate intracavitary brachytherapy (HDR) was performed in all cases. In chemotherapy, platinum based drugs were used alone or in combination with other drugs such as 5FU. Grade of late complications was scaled retrospectively with CTCv2.0. Overall survival rate at 50 months of stage Ib, II and III, IV was 82% and 66% in CR-RT and 81% and 43% in R alone, respectively. Disease-free survival rate at 50 months of stage Ib, II and III, IV was 74% and 59% in CR-RT and 76% and 52% in R alone, respectively. There was no significant difference between CT-RT and RT for overall survival and disease free survival. Univariate analysis suggested that loco-regional control was better with CT-RT, but multivariate analysis could not confirm this finding. Compared to RT alone, CT-RT caused significantly more acute and late complications. Thus, late complication (grade 3-4) free survival rate at 50 month was 69% for CT-RT and 86% for RT alone (p<0.01). The therapeutic window with concomitant radiochemotherapy and HDR brachytherapy may be narrow, necessitating a close control of dose volume parameters and adherence to systems for dose prescription.

Tumor-specific cytotoxicity and type of cell death induced by peplomycin in oral squamous cell carcinoma cell lines.

The antitumor antibiotic peplomycin showed higher cytostatic antiproliferative effect on five cultured human oral squamous cell carcinoma (OSCC) cell lines (HSC-2, HSC-3, HSC-4, Ca9-22 and NA), as compared with three human oral normal cells (gingival fibroblast HGF, pulp cell HPC and periodontal ligament fibroblast HPLF). Although the antiproliferative activity of peplomycin declined with increasing cell density, peplomycin showed tumor-specific cytotoxicity at any cell density. The five OSCC cell lines showed considerable differences in sensitivity against peplomycin; the HSC-2 cells were the most sensitive, followed by the NA, HSC-3, Ca9-22 and HSC-4 cells. Peplomycin did not induce internucleosomal DNA fragmentation in any of the five OSCC cell lines, and only slightly modified caspase-3, -8 and -9 activities in the HSC-2, Ca9-22 and NA cell lines. Electron microscopy revealed that peplomycin induced the vacuolation of mitochondria accompanying electron lucent matrices lacking cristae and the enlargement of the endoplasmic reticulum in the HSC-2 cells. These data suggest that the anti-proliferative effect of peplomycin is time-dependent, and therefore prolonged treatment with peplomycin in combination with cytotoxic chemotherapeutic agents may induce greater cytotoxic action.

Chromosome arm 1q gain associated with good response to chemotherapy in a malignant glioma. Case report.

The authors describe the case of a patient with a glioblastoma multiforme who showed remarkably good response to chemotherapy. A genetic analysis using comparative genomic hybridization (CGH) revealed that the tumor had a gain on the q arm of chromosome 1 (1q). Using CGH for a series of genetic analyses of more than 180 patients with gliomas, six were found to have a demonstrated 1q gain. Although the tumors in all six of these cases were histopathologically diagnosed as high-grade gliomas, compared with other malignant gliomas they demonstrated a good prognosis because of their favorable chemotherapeutic sensitivity. In immunohistochemical tests, most of the tumor cells in these cases were negative for O6-methylguanine-DNA methyltransferase, which antagonizes the effect of DNA-alkylating chemotherapeutic agents. The authors believed that a gain of 1q could be produced through the genetic events that cause loss of 1p, because these chromosomal aberrations have an imbalance of DNA copy number in common (1p < 1q). A gain of 1q is an infrequent chromosomal aberration and its clinical importance should be investigated in a larger study; however, patients with malignant gliomas demonstrating a 1q gain possibly show longer survival and good response to chemotherapy similar to patients with tumors demonstrating 1p loss. The importance of using genetic analysis for gliomas is emphasized in this report because it may help in selecting cases responsive to chemotherapy and because appropriate treatment for these patients will lead to progress in the treatment of malignant gliomas.

Irradiation reduces bleomycin sensitivity in cervical squamous cancer cells in vitro.

PURPOSE OF INVESTIGATION: The study was performed to examine how bleomycin (BLM) and peplomycin (PEM) should be effectively used in radiotherapy for cervical squamous cancer patients. METHODS: The effects of BLM on radiosensitivity and the effects of radiation on the sensitivity to BLM of cancer cells were investigated using the radiosensitive human cervical squamous cell carcinoma cell line ME180. RESULTS: BLM treatment did not affect radiosensitivity. However, irradiation significantly reduced cell BLM sensitivity in a dose-dependent manner. There was no significant difference in BLM sensitivity and PEM sensitivity between cells concurrently irradiated and those treated with BLM or PEM 8 h before or 8 h after irradiation. CONCLUSION: Since sensitivity to BLM is reduced during irradiation, BLM should be administered to cervical cancer patients as an adjuvant chemotherapeutic drug after completion of radiotherapy.

Retrospective Investigation of Cutaneous Squamous Cell Carcinoma on the Lip Treated with Peplomycin Administered Through a Superficial Temporal Artery.

BACKGROUND: Continuous intra-arterial (IA) administration of peplomycin (PEP) through a tumor-feeding artery is one of the most effective treatments for cutaneous squamous cell carcinoma (cSCC) in cosmetic areas. PATIENTS AND METHODS: In order to determine the effective and safe dose of PEP and the curative rate of IA-PEP, we retrospectively investigated a case series of 24 patients with cSCC on the lips who were treated with IA-PEP. RESULTS: IA-PEP reduced the tumor mass in all 24 cases (100%). A complete response occurred in 17 patients (70.8%), and a partial response occurred in seven (29.2%). Moreover, 17 patients (70.8%) were cured, three patients developed cervical lymph node metastasis (12.5%), and four developed local recurrence (16.7%). Three out of the 24 patients developed interstitial pneumonia (12.5%). CONCLUSION: Low-dose IA-PEP administered through a superficial temporal artery was a highly effective treatment that achieved a curative response for 70.8% of patients with cSCC on the lips.

Apoptosis in cervical cancer after balloon-occluded arterial infusion of anticancer drugs.

BACKGROUND: This study was designed to investigate the relationship between apoptosis and Bcl-2 and Bax expressions in uterine cervical cancer after balloon-occluded arterial infusion (BOAI). MATERIALS AND METHODS: Twenty-four specimens were obtained before and after BOAI. The occurrence of apoptosis was examined with molecular biochemical techniques. The expressions of Bcl-2 and Bax proteins were investigated by immunohistochemical staining. RESULTS: Labelling of DNA in situ indicated that apoptotic cells were sporadically seen before BOAI (6.1 +/- 1.9). Apoptotic cells apparently increased at 5 days (25.1 +/- 6.4) after BOAI The autoradiographic analysis revealed that the DNA-ladder was identified at 5 days after BOAI. Although Bcl-2 immuno-reactivity was faintly detected, the expression of Bax increased at 3 days (49.4 +/- 10.4%) after BOAI. CONCLUSION: The results indicated that treatment with BOAI resulted in transient increases of apoptosis in cervical cancer in association with the increased expression of Bax.

Re-evaluation of tumor-specific cytotoxicity of mitomycin C, bleomycin and peplomycin.

Three antitumor antibiotics, mitomycin C, bleomycin sulfate and peplomycin sulfate, were compared for their tumor-specific cytotoxicity, using human oral squamous cell lines (HSC-2, HSC-3, HSC-4, Ca9-22 and NA), human promyelocytic leukemic cell line HL-60 and human normal oral cell types (gingival fibroblast HGF, pulp cell HPC and periodontal ligament fibroblast HPLF). Among these three compounds, mitomycin C showed the highest tumor-specificity, due to its higher cytotoxic activity against human oral tumor cell lines than bleomycin and peplomycin. However, there was considerable variation of drug sensitivity among the six tumor cell lines. Mitomycin C induced internucleosomal DNA fragmentation and caspase-3, -8 and -9 activation in HL-60 cells only after 24 h. On the other hand, mitomycin C induced no clear-cut DNA fragmentation in HCS-2 cells, although it activated caspase-3, -8 and -9 to a slightly higher extent. Western blot analysis demonstrated that mitomycin C did not induce any apparent change in the intracellular concentration of anti-apoptotic protein (Bcl-2) and pro-apoptotic proteins (Bax, Bad). Electron microscopy of mitomycin C-treated HL-60 cells showed intact mitochondria (as regards to integrity and size) and cell surface microvilli, without production of an apoptotic body or autophagosome, at an early stage after treatment. The present study suggests the incomplete induction of apoptosis or the induction of another type of cell death by mitomycin C treatment.

Granisetron reduces clinical and histological response to intra-arterial neoadjuvant chemotherapy in oral squamous cell carcinoma.

Intra-arterial neoadjuvant chemotherapy (TPP) with pirarubicin, cisplatin and peplomycin produced strong primary effects on oral squamous cell carcinoma, using metoclopramide (MCA) as an anti-emetic. After clinical application of granisetron (GRN), the clinical responses to TPP observed previously were weakened. In this paper, the influence of GRN on TPP is discussed. Sixty-three cases were evaluated with regard to the primary effects of TPP and anti-emetics. GRN was used in 42 cases of the GRN group, and MCA in 21 cases of non-GRN group. The clinical response rate (complete response, CR or partial response, PR) was 95.2% in the non-GRN group, and 76.2% in the GRN group. The rate of CR in the non-GRN group was 47.6%, whereas it was 9.5% in the GRN group. The histological effects in the GRN group were significantly lower (P<0.05) than those of non-GRN group. Concerning the relationship between the clinical responses and the histological responses, 4 of the 18 CR+PR cases (22.2%) in the GRN group showed good histological responses, compared with 6 of the 14 CR+PR cases (42.9%) showing in the non-GRN group. The histological responses in the GRN group were significantly lower (P<0.05) than in the non-GRN group. Our data indicate that GRN reduces the clinical and histological responses of chemotherapy.

Enzyme immunoassay for pepleomycin, a new bleomycin analog.

An antibody directed toward pepleomycin, a new antitumor antibiotic related structurally to bleomycin, has been produced in rabbits by immunization with a pepleomycin-protein conjugate which was prepared by a novel procedure of coupling pepleomycin to mercaptosuccinylated bovine serum albumin using N-(gamma-maleimidobutyryloxy)succinimide as a coupling agent. The antiserum was monospecific to pepleomycin and showed almost no cross-reactivity with a variety of other bleomycin analogs. An enzyme immunoassay for pepleomycin has been developed utilizing this antiserum and beta-D-galactosidase-labeled pepleomycin. The lower limit of detection by this assay, which involves a double antibody technique for the separation of antibody-bound and free antigen, was 50 pg of pepleomycin per tube. Using this assay, drug levels were easily determined in blood and urine of rabbits following administration of pepleomycin in a single dose of 1.2 mg/kg i.v. This assay is also suitable for measuring pepleomycin in the presence of other drugs since the assay is not significantly affected by any other antineoplastic agents tested. Since pepleomycin is now undergoing clinical trial, the enzyme immunoassay of the drug will be a valuable tool in clinical pharmacological studies.

Selective enhancement of the cytotoxicity of the bleomycin derivative, peplomycin, by local anesthetics alone and combined with hyperthermia.

The effect of local anesthetics alone and combined with hyperthermia on the cytotoxic effect of the bleomycin derivative, peplomycin, was studied in FM3A and HeLa cells. Noncytotoxic doses of the local anesthetics procaine, lidocaine, butacaine, tetracaine, and dibucaine enhanced peplomycin cytotoxicity. This enhancement correlated with the reported anesthetic potency of these agents. Combination of lidocaine (3 to 6 mM) and moderate hyperthermia (40 and 41 degrees) greatly enhanced peplomycin cytotoxicity, although these doses of lidocaine alone were ineffective at 37 degrees, and the temperatures alone enhanced the cytotoxicity only slightly. Cell sensitization to peplomycin cytotoxicity induced by lidocaine combined with 41 degrees hyperthermia produced a decrease in cell survival that depended on the dose of lidocaine and the dose and duration of peplomycin treatment. Lidocaine at 37 or 41 degrees did not enhance the cytotoxicity of Adriamycin, mitomycin C, and cis-diamminedichloroplatinum(II), suggesting a unique interaction with peplomycin. The enhancing effect of lidocaine on peplomycin-induced cell killing was found to increase as pH increased within the range of 7.0 to 8.0.

Lethal effect of bleomycin and peplomycin on HeLa cells in multicell tumor spheroids.

The lethal effects of bleomycin and its derivative, peplomycin, were determined for HeLa S3 cells grown in multicell spheroids cocultured with human diploid fibroblasts. Both drugs were less effective for cells in spheroids than for cells grown exponentially in monolayers. However, HeLa cells from spheroids exposed to the drugs in single-cell suspension were more sensitive to the drugs than were cells in monolayers. Sequential trypsinization of spheroids after exposure to both drugs showed that the surviving fraction increased sharply with increasing depth of cell layers in the spheroids. The presence of 0.5 mM misonidazole, a hypoxic radiosensitizer, enhanced the lethal effect of peplomycin only for the cells in the deeper layer. These findings suggest that the drug resistance of cells in spheroids was due, at least in part, to the microenvironment of the deeper layers. When spheroids were incubated in fresh medium following exposure to both drugs, the cells recovered from the potentially lethal damage within 1 hr. The extent of the recovery from a fixed drug concentration was higher in cells of the superficial layers than in cells of the deeper layers. It is suggested that the limitation of the lethal effects of bleomycin and peplomycin in solid tumors may be overcome by improving the state of oxygenation of hypoxic cells and by combining either drug with one which inhibits recovery from potentially lethal damage.

Intracellular degradation of bleomycin hydrolase in two Chinese hamster cell lines in relation to their peplomycin susceptibility.

The Chinese hamster lung (V79) cell was intrinsically 10-times more resistant to peplomycin, a bleomycin-related antitumor antibiotic, than the Chinese hamster ovary (CHO) cell. This may be associated with the 3-times higher levels of recovery of bleomycin hydrolase activity of the V79 cell. The degradation of bleomycin hydrolase molecules in both V79 and CHO cells was examined using a monoclonal antibody specific for the enzyme. Labelling experiments showed that the bleomycin hydrolase in CHO cells was less stable than the comparable enzyme in V79 cells, and that 48 kDa subunits comprising bleomycin hydrolase (a homohexameric enzyme) molecules were degraded into 31 kDa forms in both cell lines. The 105,000 X g pellet (microsomes) fraction obtained after subcellular fractionation of CHO cells contained both 48 kDa subunit and 31 kDa forms of bleomycin hydrolase, while the 105,000 X g supernatant cytosol fraction yielded only 48 kDa subunit forms of the enzyme. Moreover, bleomycin hydrolase activity of both V79 and CHO cells was almost entirely recovered from the cytosol fraction. These results suggest that degradation of the 48 kDa subunit form of bleomycin hydrolase in these two lines of cultured cells into the 31 kDa form occurs on the plasma membrane or the endoplasmic reticulum, with which the resulting large number of bleomycin hydrolase molecules or degraded forms of the enzyme that have lost enzymatic activity are associated.