Enhancement of cisplatin activity by lonidamine in human ovarian cancer cells

Overexpression of miR-329-3p sensitizes osteosarcoma cells to cisplatin through suppression of glucose metabolism by targeting LDHA

Osteosarcoma (OS) is one of the most frequent malignant bone tumor types. Traditional treatments of OS involve standard chemotherapy or combination with radiation before and after surgery. Cisplatin is one of the most effective chemotherapeutic drugs used for treating osteosarcoma. However, patients with advanced tumor stages develop cisplatin resistance, leading to a major clinical challenge. In this study, we investigated the roles of miR-329-3p in cisplatin sensitivity of osteosarcoma cells. We found miR-329-3p was significantly downregulated in osteosarcoma tissues compared with normal bone tissues. Overexpression of miR-329-3p suppressed osteosarcoma cell proliferation. Moreover, we observed low-toxic cisplatin treatments suppressed miR-329-3p but higher concentrations of cisplatin-induced miR-329-3p expression. In addition, miR-329-3p was significantly downregulated in cisplatin-resistant Saos-2 cells which displayed elevated glucose metabolism. Overexpression of miR-329-3p significantly impaired glucose metabolism of Saos-2 cells. Bioinformatics analysis and luciferase assay consistently demonstrated the glycolysis enzyme, lactate dehydrogenase-A (LDHA) was a direct target of miR-329-3p in osteosarcoma cells. Rescue experiments revealed restoration of LDHA in miR-329-3p-overexpressed cisplatin-resistant cells effectively recovered glucose metabolism, resulting in increased cisplatin resistance. This study demonstrates a miR-329-3p-LDHA-glucose metabolism-cisplatin resistance axis in osteosarcoma cells, providing a miRNA-based therapeutic strategy against chemoresistant osteosarcoma.

Combination of Epirubicin and Lonidamine for Treatment of Advanced Breast Cancer

Aims and background

In vitro and in vivo studies have shown that lonidamine potentiates the cytotoxic effect of anthracyclines in simultaneous and sequential combination. On the basis of such evidence, we evaluated the activity and toxicity of a combination of epirubicin plus lonidamine in advanced breast cancer.

Methods

Between January 1991 and November 1993, 33 patients with advanced breast cancer, age <75 years and PS <2, were treated with epirubicin (75 mg/m2 i.v. on day 1, every 3 weeks), plus lonidamine (450 mg/day orally from day 1 continuously until disease progression).

Results

Thirty patients were evaluable for response: 4 achieved complete response (13%) and 8 partial response (27%) (total response rate = 40%), 6 (20%) had stabilization of disease, and 12 (40%) progression of disease. The median duration of response was 10 months (range, 4-24+ months). This scheme was tolerated, with a mild additional toxicity related to lonidamine: only WHO grade III myalgia in 1 patient (3%) and epigastralgia in 3 patients (9%).

Conclusions

Although some patients seem to have benefited from the combination at the dose levels of the drug used in the study, the therapeutic advantages of addition of lonidamine remain unclear.

Third-Line Chemotherapy with Mitomycin C and Lonidamine in Advanced Bladder Cancer. Partial Response in a Patient with Skin and Lung Metastases

Skin metastases from transitional cell carcinoma are quite rare. The present case report describes the results of a combination of mitomycin C and lonidamine administered as third-line chemotherapy in a patient with pulmonary and skin involvement from bladder cancer. The partial response obtained suggests that further testing should be carried out on the activity of this association in a second-line approach.

Treatment of Inoperable Non-small Cell Lung Carcinoma Stage IIIB and IV with Cisplatin, Epidoxorubicin, Vindesine and Lonidamine: A Phase II Study

Aims and Background

The polychemotherapeutic regimen PEV (cisplatin, epidoxorubicin and vindesine) + lonidamine proved to be valid in terms of activity and efficacy in the treatment of patients with advanced, previously untreated non-small cell lung carcinoma. The goal of the study was to verify whether a different dose of lonidamine, together with an increase in cisplatin and epidoxorubicin compared to the standard regimen, is able to improve the activity and efficacy of PEV without increasing toxicity.

Patients and Methods

Thirty-one patients were treated with cisplatin (80 mg/m2/iv), epidoxorubicin (70 mg/m2/iv) and vindesine (3 mg/m2/iv) every 28 days for 6 courses in combination with lonidamine (600 mg/day on days 1 and 2 of each course followed by 450 mg/day until progression of disease or intolerance). All the patients were monitored for clinical response, median duration of response and survival and for toxicity.

Results

The clinical response in the 29 assessable patients was: 41.4% partial remission, 48.3% stable disease, and 10.3% progression of disease. The median duration of response was 8.5 months (range, 4-26+) and median survival was 12 months (range, 4-26+). Survival was above the median in 15 stage lIIb patients, and 2 patients were long survivors at 26+ months. The toxicity of PEV + lonidamine was mild; there were no toxic deaths nor acute toxicity of grade 4 according to the WHO scoring system.

Conclusions

Our polychemotherapeutic regimen proved to be valid in terms of activity and efficacy, and a further dose increase in single chemotherapeutic agents as well as lonidamine could therefore be justified.

Lonidamine plus Cyclophosphamide in the Treatment of Adanced Non-Small Cell Lung Cancer in the Elderly: A Phase II Study

Aim and background

The aim of this Phase II trial was to verify the therapeutic activity and tolerability of chemotherapy with lonidamine (LND) plus cyclophosphamide (CTX) in advanced non-small cell lung cancer (NSCLC) in the elderly. The rationale of the combination is reported. CTX showed mild toxicity, with a 12% objective response (OR) in monochemotherapy; LND potentiated the in vitro antiproliferative activity of alkylating agents, mainly CTX, without increasing myelotoxicity, particularly important in the elderly.

Methods

The schedule consisted of CTX, 600 mg/m2/i.v. on day 1 every 21 days for 6 cycles; LND, 450 mg/die/p.o. from day 1 to progression.

Results

Between November 1990 and April 1991, 41 patients with stage III–IV NSCLC were enrolled; 35 were assessable for response. Median age was 73 years (range, 71–79 years); 13 patients (32%) presented stage III A, 20 (49%) stage III b, and 8 (19%) stage IV disease. Cardiovascular conditions and/or chronic respiratory failure contraindicated surgical treatment in stage III A patients. Of enrolled patients, 14.6% experienced PR, 48.8% SD and 14.6% dropped out of the study. Median time to progression was 4 months (range, 2–9 months) and median survival 9 months (range 3–45 months). No patient showed WHO grade IV LND-related toxicity. In 1 patient (2.5%), LND was discontinued after 5 therapy cycles due to WHO grade III myalgia; in 80% of patients, LND oral dosage was reduced to 300 mg/day due to WHO grade II myalgia, and 20% of patients completed treatment with the full dose.

Conclusions

CTX plus LND can be considered a well tolerated therapeutic approach in the elderly with NSCLC with good PS and good liver, renal and cardiac conditions, but 14.6% PR is a slightly better result as compared with 12% PR obtainable with CTX alone as reported in the literature, even though most patients presented with advanced disease and no specific toxic effect was observed. Therefore, a confirmatory randomized trial (CTX vs CTS plus LND) would hardly be useful.

Telomere dysfunction increases cisplatin and ecteinascidin-743 sensitivity of melanoma cells

The aim of this study was to investigate the role of telomerase function on the chemosensitivity of melanoma cells. To this end, ecteinascidin-743 (ET-743) and cisplatin [cis-diamminedichloroplatinum(II) (CDDP)], two DNA-interacting drugs that invariably cause an arrest in the G(2)/M phase, and 1-(2,4-dichlorobenzyl)-1H-indazole-3-carboxylic acid (LND), a mitochondria-targeting drug inducing a G(1) block, were used. As experimental model, human melanoma clones showing reduced human telomerase reverse transcriptase (hTERT) expression and telomerase activity and characterized by telomere dysfunction were used. Reconstitution of telomerase activity by exogenous hTERT expression improved telomere function and reduced the sensitivity to CDDP and ET-743 without affecting LND susceptibility. The decreased sensitivity to CDDP and ET-743 was mainly caused by the ability of cells to recover from drug-induced damage, evaluated in terms of both chromosomal lesions and cell survival. The ability of hTERT-reconstituted cells to recover from drug-induced damage was attributable to the restoration of cell cycle progression. In fact, the cells without hTERT restoration remained for a prolonged time in the G(2)/M phase, and this cell cycle alteration made irreversible the drug-induced S-G(2)/M block and led to the activation of apoptotic program. On the contrary, the hTERT-reconstituted cells progressed quickly through the cell cycle, thus acquiring the capacity to recover from drug-induced block and to protect themselves from the G(2)/M phase-specific drug-triggered apoptosis.

Time to progression in metastatic breast cancer patients treated with epirubicin is not improved by the addition of either cisplatin or lonidamine: final results of a phase III study with a factorial design

PURPOSE

To investigate the value of the addition of either cisplatin (CDDP) or lonidamine (LND) to epirubicin (EPI) in the first-line treatment of advanced breast cancer.

PATIENTS AND METHODS

Three hundred seventy-one metastatic breast cancer patients with no prior systemic chemotherapy for advanced disease were randomized to receive either EPI alone (60 mg/m(2) on days 1 and 2 every 21 days), EPI and CDDP (30 mg/m(2) on days 1 and 2 every 21 days), EPI and LND (450 mg orally daily, given continuously), or EPI, CDDP, and LND. Time to progression, response rates, side effects, and survival were compared according to the 2 x 2 factorial design of this study.

RESULTS

The groups were well balanced with respect to prognostic factors. Time to progression did not differ in the comparison between CDDP arms and non-CDDP arms (median, 10.9 months v 9.4 months, respectively; P =.10) or between that of LND arms and non-LND arms (median, 10.8 months v 9.9 months, respectively; P =.47), nor did overall survival. The response rate did not significantly differ in the comparison between LND arms and non-LND arms (62.9% v 54.0%, P =.08). No difference in treatment activity was observed between CDDP arms and non-CDDP arms. Toxicity was significantly higher in the CDDP arms, leading to CDDP dose adjustment in 40% of cases. The most frequent side effects were of a hematologic and gastrointestinal nature. The addition of LND produced more myalgias and fatigue.

CONCLUSION

Neither CDDP nor LND was able to significantly improve the time to progression obtained by EPI. CDDP, however, significantly worsened the drug's tolerability.

Mitochondria-targeting drugs arsenic trioxide and lonidamine bypass the resistance of TPA-differentiated leukemic cells to apoptosis

Exposure of U937 human leukemic cells to the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) induces their differentiation into monocyte/macrophage-like cells. This terminal differentiation is associated with a resistant phenotype to apoptosis induced by the topoisomerase II inhibitor etoposide. The inhibition occurs upstream of the mitochondrial release of cytochrome c and the activation of procaspase-2, -3, -6, -7, -8, and -9. By using cell-free systems, it was demonstrated that the mitochondrial pathway to cell death that involves mitochondrial membrane depolarization, cytochrome c release and cytosolic activation of procaspases by cytochrome c/dATP remains functional in TPA-differentiated U937 cells. Accordingly, 2 drugs recently shown to target the mitochondria, namely lonidamine and arsenic trioxide, bypass the resistance of TPA-differentiated U937 cells to classical anticancer drugs. Cell death induced by the 2 compounds is associated with mitochondrial membrane depolarization, release of cytochrome c and Smac/Diablo from the mitochondria, activation of caspases, poly(ADP-ribose) polymerase cleavage and internucleosomal DNA fragmentation. Moreover, the decreased glutathione content associated with the differentiation process amplifies the ability of arsenic trioxide to activate the mitochondrial pathway to cell death. Similar results were obtained by comparing undifferentiated and TPA-differentiated human HL60 leukemic cells. These data demonstrate that mitochondria-targeting agents bypass the resistance to classical anticancer drugs induced by TPA-mediated leukemic cell differentiation. (Blood. 2001;97:3931-3940)

Paclitaxel, cisplatin and lonidamine in advanced ovarian cancer. A phase II study

A potential way to improve the results obtained with the standard carboplatin/cisplatin (CDDP)-paclitaxel treatment regimen in advanced ovarian cancer is to incorporate a modulating agent such as lonidamine (LND). In fact, LND has been shown to revert the resistance to cisplatin and to potentiate cisplatin activity experimental models and in clinical studies. 35 consecutive patients with advanced ovarian cancer, not previously treated with chemotherapy were treated with paclitaxel at a dose of 135 mg/m(2) intravenously (i.v.) on day 1 (in a 3 h infusion) and cisplatin at a dose of 75 mg/m(2) iv on day 2 plus LND orally (p.o.) at a dose of 450 mg/die for 6 consecutive days starting two days before chemotherapy, every 3 weeks for six cycles. Complete plus partial responses were observed in 8 (80%) out of the 10 women with measurable disease. In the 25 patients with evaluable disease, only four clinical progressions were observed (16%). Median progression-free survival (PFS) and overall survival (OS) were 28.5 (95% confidence interval (CI) 22.2-34.8) and 46.5 (95% CI 32.4-60.00) months respectively. Grade 3-4 neutropenia was observed in 9 (26%) patients. Alopecia, nausea and vomiting (Grade 3) were observed in 33 (94%) and 5 (14%) patients, respectively. In conclusion, the combination of CDDP/paclitaxel plus LND is active and tolerable in the treatment of advanced ovarian cancer.

Combined 4-hydroxy-ifosfamide and vinorelbine treatment in established and primary human breast cell cultures

BACKGROUND

Vinorelbine and ifosfamide are active drugs against breast cancer, but the best treatment schedule has yet to be defined by preclinical or clinical studies. The antitumor activity of 4-hydroxy-ifosfamide (4-OH-IF), the active form of ifosfamide, and vinorelbine (VNB) and their interaction were investigated in two established breast cancer cell lines (MCF-7 and BRC-230) and in 10 primary breast cancer cultures.

MATERIALS AND METHODS

Cytotoxic activity was evaluated by a highly efficient clonogenic assay (HECA). The median-effect principle was applied to evaluate synergistic and antagonistic interactions and the corresponding combination index values were calculated. Cell cycle perturbations were analysed by flow cytometry.

RESULTS

In MCF-7 and BRC-230 cell lines the sequence VNB for 4 hours followed by 4-OH-IF for 24 hours produced an antagonistic effect. Conversely, the inverse sequential scheme, 4-OH-IF-->VNB provided synergistic effects on both cell lines. The synergism was associated with a strong block in the G2-M phase. Synergistic activity of 4-OH-IF-->VNB sequence was confirmed in 7 of 10 primary breast cancer cultures.

CONCLUSIONS

In conclusion, the sequence 4-OH-IF-->VNB appeared to be the most effective scheme both in established cell lines and in primary breast cancer cultures.

Weekly epirubicin plus lonidamine in advanced breast carcinoma

Lonidamine has been demonstrated to potentiate the cytotoxic activity of several antineoplastic drugs, for example anthracyclines. Moreover, epirubicin is considered one of the most active drugs in advanced breast cancer, although optimal dose and schedule remains to be defined. In the present study we have treated 51 patients with advanced breast cancer with a combination of lonidamine (450 mg/day orally from day 1 throughout treatment) and epirubicin (25 mg/m2 i.v.) administered according to a weekly schedule for 24 weeks. Objective responses were observed in 29 out of 51 patients (57%; CR 16%, PR 41%). Liver metastases responded in eight out of 12 evaluable patients (67%). Average response duration was 12.4 months and median overall survival was 23 months (range 1-90+). Toxicity was negligible. The combination of weekly epirubicin and lonidamine is feasible and active in advanced breast cancer patients.

Schedule-dependent interaction of doxorubicin, paclitaxel and gemcitabine in human breast cancer cell lines

We showed previously that a sequential treatment with doxorubicin (4 hr) followed by paclitaxel (24 hr) (Dox-->Pacl) induces a synergistic cytotoxic effect in the BRC-230 breast cancer cell line and in human primary breast cancer cultures. The validity of this experimental finding was confirmed in a clinical phase I/II study on advanced breast cancer patients. To improve the cytotoxic effect obtained by the Dox-->Pacl sequence, we analyzed the effect of adding gemcitabine (Gem) to the Dox-->Pacl sequence in a preclinical study. Our study was performed on BRC-230 and MCF-7 cell lines, and cytotoxic activity was evaluated by the sulforhodamine B assay and the type of drug interaction by Drewinko's test. When Gem (0.01 microg/ml for 24 hr) was given immediately or 24 hr after Dox-->Pacl, an antagonistic cytotoxic effect was observed. Conversely, a synergistic effect was found when Gem was given 48 hr after Dox-->Pacl. From results of flow cytometric analysis, the synergistic effect was attributed to cell cycle perturbation. Cells were arrested in G2-M (95% in treated vs. 21% in control samples) 24 hr after Dox-->Pacl treatment. The block progressively recovered thereafter, and after a further 24 hr, at the time of Gem treatment, the cells progressed into the G1-S phase boundary (the cell cycle phase susceptible to the cytocidal effect of the drug). Our findings suggest that the interactions of Dox, Pacl and Gem are highly schedule- and time-dependent and should be taken into consideration in the planning of clinical protocols.

Lonidamine as a modulator of taxol activity in human ovarian cancer cells: effects on cell cycle and induction of apoptosis

The ability of lonidamine (LND), an energolytic derivative of indazole-carboxylic acid, to modulate the cytotoxicity of Taxol (TX) was investigated in the A2780 human ovarian cancer cell line. Different cytotoxicity results were obtained as a function of treatment schedule. Specifically, TX followed by LND produced synergistic effects. Conversely, antagonistic effects were recorded when drugs were given simultaneously or according to the opposite sequence. TX induced an oligonucleosomal DNA fragmentation typical of the apoptotic process. The extent and the kinetics of DNA cleavage in samples treated with the taxane alone were similar to those of samples treated with the TX-LND sequence. Activation of Yama protease and degradation of poly (ADP-ribose) polymerase were not observed after individual or combined treatment. LND did not appreciably modify the effect exerted by TX on proteins involved in cell cycle progression (i.e., inhibition of p34cdc2 expression) and apoptosis (i.e., upregulation of wt p53 and transactivation of p21waf1), and only caused a slight induction of the Bax protein. LND alone did not affect tubulin polymerization in A2780 cells and, when administered after a 24 hr TX exposure, did not appreciably alter the extent of tubulin polymerization induced by the taxane. Although additional studies are needed to define the molecular basis of the TX-LND interaction, our results suggest that LND can positively modulate the antitumor activity of TX in ovarian cancer cells and indicate that the energolytic is potentially useful in combination therapy including the taxane in ovarian cancer patients.

Modulating effect of lonidamine on response to doxorubicin in metastatic breast cancer patients: results from a multicenter prospective randomized trial

Previous results from our preclinical studies have shown that lonidamine (LND) can positively modulate the antiproliferative activity of doxorubicin (DOX) on breast cancer cell lines. To evaluate the effect of LND in a clinical setting, a multicenter randomized trial was carried out on patients with advanced breast cancer. From September 1991 to July 1993, 181 patients were enrolled in the trial and received an initial treatment of DOX at 75 mg/m2 for 3 cycles. The 137 patients who reached complete remission, partial remission, or stable disease were randomized to receive either DOX alone (75 mg/m2 day 1) (arm A) or DOX plus LND (600 mg orally/day) (arm B). The patients enrolled in the two arms were fairly homogeneous in terms of major clinical characteristics. Toxicity was similar in both arms except for myalgia: WHO grade > or=2 was observed in 57% of arm B patients. Overall response rate to DOX + LND was 50% and to DOX alone 38% in evaluable patients, and 48% vs 37% in all registered patients, as determined by an intention-to-treat analysis. The differences did not reach statistical significance. Conversely, in agreement with previous findings, we observed a significant difference in response rate in the subgroup of patients with liver metastases, regardless of the extent of hepatic involvement (DOX + LND 68% vs DOX 33%, p=0.03). This observation makes LND an important tool in association with anthracyclines in the treatment of this subgroup of patients.

Potential complications associated with normothermic lonidamine infusion and with systemic acidosis in dogs receiving lonidamine during whole body hyperthermia (WBH)

The vascular toxicosis of lonidamine (40 mg/h) or vehicle infusion was investigated in six dogs. Vasculitis and thrombosis were observed in veins infused with lonidamine but not in veins infused with vehicle. This finding suggests that it may not be possible to use lonidamine infusion to circumvent therapeutic limitations associated with the oral lonidamine formulation currently used in patients. We also investigated the systemic toxicosis of lonidamine (400 mg/m2; rapid intravenous bolus) or vehicle in six other dogs that developed systemic acidosis (pH < or = 7.0) during whole body hyperthermia (42 degrees C x 90 min). Gross and histologic haemorrhage was observed in all dogs; however, haemorrhagic lesions in acidotic dogs receiving lonidamine + WBH were more severe than changes observed in acidotic dogs receiving vehicle + WBH. These observations confirm the results of in vitro studies which suggest that the combined effect of lonidamine and hyperthermia is enhanced under acidic conditions. Furthermore, these findings indicate that acid-base status of patients receiving lonidamine during WBH must be monitored carefully to avoid serious complications.

Treatment of patients with advanced gastric carcinoma with a 5-fluorouracil-based or a cisplatin-based regimen: two parallel randomized phase II studies

BACKGROUND

Although many drug combination therapies have been proposed, there is no standard therapy for patients with advanced gastric carcinoma. The superiority of combination therapy over monochemotherapy has not been demonstrated convincingly. To explore the role of monochemotherapy, the authors evaluated 5-fluorouracil (5-FU), modulated by 6S-leucovorin (6S-LV) and a cisplatin-containing regimen, which was comprised of epirubicin, etoposide, and cisplatin with the addition of the reversal agent lonidamine (EEP-L).

METHODS

After stratification according to performance status (PS) and resection of the primary tumor, 72 patients with advanced gastric carcinoma were randomized to 2 parallel Phase II trials with 5-FU/6S-LV and EEP-L, respectively. Thirty-six patients in Study A received bolus 6S-LV, 100 mg/m2, followed by bolus 5-FU, 370 mg/m2, on Days 1-5 and 36 others in Study B received epirubicin, 30 mg/m2, on Days 1 and 5; etoposide, 100 mg/m2, on Days 1, 3, and 5; cisplatin, 30 mg/m2, on Days 2 and 4; and lonidamine, 150 mg/day.

RESULTS

There were 6 partial responses (18.2%) (95% confidence interval [CI] +/- 13.2) in Study A and 7 partial responses (21.9%) (95% CI +/- 14.3) in Study B. Partial responses were more frequent in patients with resected tumors or with an Eastern Cooperative Oncology Group PS of 0-1. The median duration of response was 8.8 and 8.3 months, respectively, in Study A and Study B. The median survival reached 8 months in Study A and 9 months in Study B. In the whole population of patients survival was significantly higher in patients with a PS of 0-1 (P < 0.05). Patients with a PS of 0-1 and a resected tumor had the significantly longest survival both in EEP-L treated patients and in all evaluable patients in the two studies. The most frequent World Health Organization Grade 3-4 toxic effects were gastrointestinal in Study A and hematologic in Study B. No treatment-related death was observed.

CONCLUSIONS

The efficacy of 5-FU, modulated with 6S-LV, is moderate in patients with advanced gastric carcinoma, similar to cisplatin-containing regimens. PS and other prognostic factors could influence the response rate, which does not appear to be a reliable parameter for evaluating the outcome of chemotherapy trials.

Modulation by lonidamine on the combined activity of cisplatin and epidoxorubicin in human breast cancer cells

The ability of lonidamine (LND), an energolytic derivative of indazole-carboxylic acid, to modulate the cytotoxic activity of cisplatin (CDDP) and epidoxorubicin (EPI), singly or in combination, was investigated in two human breast cancer cell lines (MCF7 and T47D). A 72-hr post-incubation with a non-cytotoxic concentration of LND (75 microM) increased the activity of a 1-hr CDDP treatment as well as that of a 1 to 16-hr EPI treatment. A different pattern of interaction among the drugs and modulator was observed as a function of the sequence of drug treatment. Specifically, supra-additive or additive effects of the combination were obtained in the two cell lines according to the different treatment schemes. In particular, the maximum potentiation was observed in MCF7 cells simultaneously exposed to CDDP, EPI and LND for 1 hr and then post-incubated with LND for 72 hr, and in T47 first exposed to EPI and LND, then to CDDP and LND, and finally post-incubated with LND. Flow cytometric analysis of MCF7 cell distribution in the different cycle phases showed that combined treatment with EPI/CDDP/LND was able to stabilize cell cycle perturbations (mainly G2M accumulation) induced by individual agents. The ability of LND to potentiate CDDP and EPI cytotoxicity, and the consideration that LND causes side effects different from those caused by alkylating agents and anthracyclines, make this compound an attractive candidate for multidrug combination therapy in breast cancer.

Effects of the inhibitors of energy metabolism, lonidamine and levamisole, on 5-aminolevulinic-acid-induced photochemotherapy

The ability of endogenously synthesized protoporphyrin IX (PpIX) to damage Chinese hamster lung fibroblasts of the line V79 by exposure to light was examined. This treatment induced reduction of cellular ATP, GTP, of the NADH/NAD+ ratio and of oxygen consumption. The present results indicate a close relationship between inhibition of respiration of irradiated cells and their ability to survive, e.g. 1 min of light exposure induced 90% inhibition of oxygen consumption and inactivation of approximately 95% of the cells, while the cellular content of ATP was reduced by only 15%. This indicates that the mitochondria are one of the primary targets of 5-aminolevulinic acid (ALA)-mediated photochemotherapy (PCT). In the present study, ALA-PCT was combined with the modulators of the glycolysis and the respiration chain, levamisole (LEV) and lonidamine (LND). A synergistic effect of combining ALA-PCT with non-toxic concentrations of LND was observed when LND was given prior to light exposure. This synergism was observed despite a substantial LND-induced inhibition of PpIX formation. At increasing doses of LND (>0.15 mM) the combination treatment becomes less efficient. This is due to the inhibition of PpIX synthesis induced by LND. A synergistic effect of ALA-PDT and LEV was found when LEV was given prior to light exposure. This was at least partly due to an LEV-stimulated effect on ALA-induced PpIX formation. However, it is not clear from the present results whether LEV may perturb energy metabolism in V79 cells since LEV alone did not reduce the energy charge or the NADH/NAD+ ratio. When LEV or LND were given after ALA-PCT, these 2 treatment modalities acted in an additive or slightly synergistic manner.

Lonidamine induces apoptosis in drug-resistant cells independently of the p53 gene

Lonidamine, a dichlorinated derivative of indazole-3-carboxylic acid, was shown to play a significant role in reversing or overcoming multidrug resistance. Here, we show that exposure to 50 microg/ml of lonidamine induces apoptosis in adriamycin and nitrosourea-resistant cells (MCF-7 ADR(r) human breast cancer cell line, and LB9 glioblastoma multiform cell line), as demonstrated by sub-G1 peaks in DNA content histograms, condensation of nuclear chromatin, and internucleosomal DNA fragmentation. Moreover, we find that apoptosis is preceded by accumulation of the cells in the G0/G1 phase of the cell cycle. Interestingly, lonidamine fails to activate the apoptotic program in the corresponding sensitive parental cell lines (ADR-sensitive MCF-7 WT, and nitrosourea-sensitive LI cells) even after long exposure times. The evaluation of bcl-2 protein expression suggests that this different effect of lonidamine treatment in drug-resistant and -sensitive cell lines might not simply be due to dissimilar expression levels of bcl-2 protein. To determine whether the lonidamine-induced apoptosis is mediated by p53 protein, we used cells lacking endogenous p53 and overexpressing either wild-type p53 or dominant-negative p53 mutant. We find that apoptosis by lonidamine is independent of the p53 gene.

Fludarabine as a modulator of cisplatin activity in human tumour primary cultures and established cell lines

The potential of the purine analogue fludarabine (9-beta-D-arabinofuranosyl-2-fluoroadenine-5' monophosphate) as a modulator of cisplatin cytotoxicity was investigated in four established cell lines and 20 primary cultures of human melanoma and ovarian cancer. Tumour cells were exposed to fludarabine and cisplatin, alone or in combination, for 4 h. Fludarabine did not affect the growth of ovarian cancer cell lines, whereas it induced a marked and dose-dependent inhibition of proliferation in melanoma cell lines. In primary cultures of both histotypes, the purine analogue did not induce appreciable antiproliferative effects. Combined cisplatin-fludarabine treatment caused additive effects in all established cell lines. Conversely, a synergistic effect of the combination was seen in 5 of 10 melanoma and 4 of 10 ovarian cancer primary cultures, with a dose-modifying factor ranging from 2.1 to 3.9 for melanomas and from 4.0 to 7.5 for ovarian cancers, respectively. In the remaining cultures, the interaction between fludarabine and cisplatin was additive. The alkaline filter elution analysis performed on primary cultures showed that the synergistic interaction between the two drugs was paralleled by an increase in the extent and persistence of the cisplatin-induced DNA interstrand crosslinks. Our results indicate that fludarabine can enhance cisplatin cytotoxic activity in human tumour primary cultures from ovarian cancer and malignant melanoma. Such an effect may be partially due to an interference by fludarabine on cisplatin-induced DNA adduct metabolism and repair.

Cisplatin, epirubicin, and vindesine with or without lonidamine in the treatment of inoperable nonsmall cell lung carcinoma: a multicenter randomized clinical trial

BACKGROUND

Lonidamine (LND) is an indazol-carboxylic acid derivative that selectively inhibits the energy metabolism of neoplastic cells, and increases the permeability of cell membranes. In vitro studies have demonstrated that LND can potentiate the oncolytic activity of cytotoxic drugs and is able to reverse the acquired multidrug resistance of neoplastic cells. Some clinical trials have suggested a synergism of LND with alkylating agents, cisplatin, and anthracyclines in various solid tumors.

METHODS

From June 1990 to June 1993, 158 previously untreated patients with Stage IIIB and IV nonsmall cell lung cancer (NSCLC) were enrolled into a multicentric randomized trial to evaluate the addition of LND to a cisplatin-epirubicin-vindesine regimen. Eighty patients in the control arm (A) received cisplatin, 60 mg/m2 intravenously (i.v.); epirubicin, 60 mg/m2 i.v.; and vindesine, 3 mg/m2 i.v. (PEV), on Day 1 every 4 weeks, whereas 78 patients in the experimental arm (B) received the same regimen with the addition of LND from 75 mg orally three times on Day 1 to 150 mg orally three times on Day 7+ until tumor progression occurred.

RESULTS

The experimental treatment achieved a significantly higher proportion of major responses in comparison with the control regimen (43% vs. 24%; P=0.02). The addition of LND apparently potentiated the activity of this cytotoxic treatment, particularly in patients with metastatic disease (overall response rate, 39% vs. 17%). The median time to progression (5 vs. 8 months; P=0.0007) and the median survival time (7.6 vs. 11 months; P=0.0013) were also statistically improved in Arm B. The acute toxicity of the 2 treatments was low: only 6% of patients in Arm A and 4% of patients in Arm B had to withdraw from treatment due to Grade 4 World Health Organization toxicity. The main additional side effects related to the administration of LND were epigastralgia, myalgia, asthenia, and orchialgia. However, these symptoms were mild and controlled by the concomitant administration of low doses of steroids.

CONCLUSIONS

The mild acute toxicity of the PEV regimen and the acceptable and nonoverlapping additional side effects of LND render our experimental therapy worthy of consideration for the management of NSCLC patients with poor performance status or low tolerance to more aggressive therapeutic approaches.

An on-line semi-automated solid-phase extraction procedure for high-performance liquid chromatographic determination of lonidamine in serum

A semi-automated solid-phase extraction procedure on-line with gradient elution reversed-phase chromatography permits the determination of lonidamine and its metabolite in human serum. The average recovery from serum at the 2.5 micrograms ml-1 level was (92.8 +/- 3.4)%. The limit of quantitation for a 100 microliter sample size was 50 ng ml-1. The within-day (n = 5) and between-day (n = 5) relative standard deviations for lonidamine determination in serum samples spiked at the 2.5 micrograms ml-1 level were 2.7% and 4.5%, respectively.

Phase II study of high-dose epirubicin, lonidamine, alpha 2b interferon in advanced breast cancer

44 patients with advanced breast cancer were treated with high-dose epirubicin (130 mg/sqm), because of its steep dose-response curve. Lonidamine and alpha interferon were administered as well with the aim of increasing epirubicin uptake and overcoming drug resistance. Granulocyte-colony stimulating factor support was provided. 14 complete responses and 22 partial responses were observed in 40 evaluable patients for a 90% overall response rate. Median duration of response was 12 months for complete responders, 7 months for partial responders. In two cases the complete response has lasted for more than two years. Myelosuppression, infection, and cardiac toxicity were the main treatment-related toxic effects. These results are encouraging enough to justify a randomized comparison of our chemotherapy program with standard regimens used in advanced breast cancer.

Relative cytotoxicities of adriamycin and epirubicin in combination with lonidamine against human bladder cancer cell lines

We have used a panel of bladder cancer cell lines to compare the toxicities of Adriamycin and epirubicin, two drugs used intravesically to treat superficial transitional cell cancer (TCC) of the bladder, alone and in combination with lonidamine, an agent known to be active against anthracycline-resistant disease. Comparing concentrations reducing colony-forming ability by 50%, epirubicin and Adriamycin were similar in their cytotoxicities, although epirubicin was more potent against every line except an Adriamycin-resistant subline. Combinations of the two drugs with a non-cytotoxic concentration (1 microgram/ml) of lonidamine were tested using the Adriamycin-resistant subline MGH-U1R and its sensitive parental line MGH-U1. The addition of lonidamine caused a two-fold increase in the sensitivity of the resistant subline to both drugs, while having no effect on the sensitivity of the parental line. The data indicate that this combination might be of value in anthracycline-resistant disease.

Potentiation of cis-diammine(1,1-cyclobutanedicarboxylato)platinum(II) by amphotericin B in BALB/c nude mice bearing human ovarian carcinoma cells

Human ovarian carcinoma cells (HRA) were sensitized to cis-diammine(1,1-cyclobutanedicarboxylato)platinum(II) (CBDCA) 1.2-, 2.1- and 3.4-fold by treatment with amphotericin B (AMB) at concentrations of 2.1, 5.4, and 10.8 microM, respectively. Moreover, the intracellular accumulation of platinum after 2-h exposure to CBDCA was increased significantly by AMB treatment. For estimating the enhancing effect of AMB on CBDCA cytotoxicity in vivo, we prepared HRA cell-inoculated nude mice. Ascites was evident 7 to 9 days after intraperitoneal (i.p.) inoculation of HRA cells, and the mice died of intraabdominal carcinomatosis 11 to 14 days (mean survival time (MST): 12.0 +/- 1.0 days) after inoculation. Treatment with AMB (2.0 mg/kg) alone increased the MST by only 1.2 days. Simultaneous treatment with CBDCA (12 or 15 mg/kg) and AMB (0.5 to 2.0 mg/kg) produced a significant increase in MST compared to treatment with CBDCA alone. Maximal MST (38.5 days) was obtained by treatment with 15 mg/kg CBDCA plus 2.0 mg/kg AMB, whereas the MST with 15 mg/kg CBDCA alone was 15.8 days. A drug accumulation study demonstrated that platinum accumulation in tumor tissues after i.p. treatment with CBDCA and AMB in tumor-bearing nude mice was increased significantly compared to treatment with CBDCA alone. These findings indicate that intraperitoneal combination chemotherapy with CBDCA and AMB is useful in nude mice with advanced ovarian carcinoma.

Elevated doses of carmustine and mitomycin C, with lonidamine enhancement and autologous bone marrow transplantation in the treatment of advanced colorectal cancer: results from a pilot study

10 patients with advanced colorectal cancer were treated with elevated doses of carmustine and mitomycin C. The regimen was potentiated by lonidamine and supported by autologous bone marrow transplantation. The results of this pilot study were encouraging, with a response rate of 50% and a significantly better survival for responders versus non-responders. No appreciable toxicity of the therapy was observed. This aspect, together with the simplicity of the procedure, calls for further investigations to confirm the good therapeutic index of the treatment.

In vitro effect of lonidamine on the cytotoxicity of mitomycin C and BCNU in human colon adenocarcinoma cells

The ability of lonidamine (LND), an energolytic derivative of indazole carboxylic acid, to modulate the cytotoxic activity of mitomycin C (MMC) and 1,3,bis(2-chloroethyl)-1-nitrosourea (BCNU) was investigated in two human adenocarcinoma cell lines (LoVo and HT29) expressing different sensitivity profiles to the drugs. After a 1-h treatment with MMC or BCNU, cells were postincubated for 24 h with 150-225 microM LND. In the LoVo cells, a synergistic interaction between LND and MMC or BCNU was observed at both LND concentrations. In HT29 cells, only additive effects of the drugs given in sequence were seen. Flow cytometric analysis indicated that LND was generally able to stabilise the cell cycle perturbations induced by MMC and BCNU in the two cell lines. The ability of LND to potentiate anticancer drug activity, and the consideration that LND causes side-effects different from those of conventional antitumour drugs, make this compound an attractive candidate for multidrug combination therapy in colon cancer.

Iron granules in plasma cells

Resistance of cancer cells to chemotherapy is the first cause of cancer-associated death. Thus, new strategies to deal with the evasion of drug response and to improve clinical outcomes are needed. Genetic and epigenetic mechanisms associated with uncontrolled cell growth result in metabolism reprogramming. Cancer cells enhance anabolic pathways and acquire the ability to use different carbon sources besides glucose. An oxygen and nutrient-poor tumor microenvironment determines metabolic interactions among normal cells, cancer cells and the immune system giving rise to metabolically heterogeneous tumors which will partially respond to metabolic therapy. Here we go into the best-known cancer metabolic profiles and discuss several studies that reported tumors sensitization to chemotherapy by modulating metabolic pathways. Uncovering metabolic dependencies across different chemotherapy treatments could help to rationalize the use of metabolic modulators to overcome therapy resistance.