Targeting the epigenome in malignant melanoma: Facts, challenges and therapeutic promises.

Malignant melanoma is the most lethal type of skin cancer with high rates of mortality. Although current treatment options provide a short-clinical benefit, acquired-drug resistance highlights the low 5-year survival rate among patients with advanced stage of the disease. In parallel, the involvement of an aberrant epigenetic landscape, (e.g., alterations in DNA methylation patterns, histone modifications marks and expression of non-coding RNAs), in addition to the genetic background, has been also associated with the onset and progression of melanoma. In this review article, we report on current therapeutic options in melanoma treatment with a focus on distinct epigenetic alterations and how their reversal, by specific drug compounds, can restore a normal phenotype. In particular, we concentrate on how single and/or combinatorial therapeutic approaches have utilized epigenetic drug compounds in being effective against malignant melanoma. Finally, the role of deregulated epigenetic mechanisms in promoting drug resistance to targeted therapies and immune checkpoint inhibitors is presented leading to the development of newly synthesized and/or improved drug compounds capable of targeting the epigenome of malignant melanoma.

Dexamethasone plus octreotide regimen increases anticancer effects of docetaxel on TRAMP-C1 prostate cancer model.

AIM: The aim of this study was to evaluate whether the neoadjuvant use of the dexamethasone (DEX) plus octreotide (OCT) regimen can improve the direct anticancer effects of docetaxel (DOC) in the TRAMP-C1 prostate cancer model. MATERIALS AND METHODS: TRAMP-C1 cells were first characterized for the expression of SSTR1-5 and then were inoculated onto the femur of C57Bl mice. Investigation protocols employed TRAMP-C1 cell proliferation and invasion assays, analysis of radiographic images of the bone lesions and overall survival of the diseased animals. RESULTS: The triple combination treatment scheme showed significant anticancer effects, in both proliferation and invasion assays, compared to any single agent treatment scheme. DOC treatment following the neoadjuvant administration of DEX plus OCT regimen improved significantly the anticancer effects both on the grading of the bone lesions and on the overall survival of the diseased animals. CONCLUSION: Our data suggest that the neoadjuvant administration of DEX plus OCT regimen can improve the anticancer effects of DOC on the TRAMP-C1 model.

Treatment with trabectedin: should be indicated to all soft tissue sarcoma histotypes?

Trabectedin is a novel antineoplastic agent approved as monotherapy in patients with advanced soft tissue sarcoma (STS) after failure of standard therapy with anthracyclines or ifosfamide, or patients who are unsuited to receive these agents. Some histotypes of STSs appear to be particularly sensitive to trabectedin, but the sensitivity of some rare STSs histological subtypes to the drug is rather unknown. We report on two patients suffering from infrequent subtypes of STSs, fibrosarcoma and epithelioid sarcoma, who were treated with trabectedin. In these cases the treatment completely failed, and right after the first cycle of trabectedin administration an unusually rapid tumor growth and dissemination was documented. Of note, one of the patients showed objective response to MVIP chemotherapy (methotrexate, etoposide, ifosfamide and cisplatin), after trabectedin failure. Trabectedin activity against several subtypes has not been studied or well-documented due to the rarity and numerous histotypes of STSs. Case studies aiming at the individualization of treatment options against specific STS subtypes will further justify the usage of this agent in clinical practice.

Rapid improvement of extensive non-melanoma skin cancers with combination of 13-cis-retinoic acid and radiotherapy: report of three cases.

Extensive non-melanoma skin cancer (NMSC) constitutes a therapeutic challenge especially in old and debilitated patients. Applied treatments include surgical excision, MOHS micrographic surgery, cryosurgery, electrodesiccation, and radiotherapy. We present 3 elderly patients with extensive basal or squamous cell carcinomas and poor general condition who were treated with a combination of 13-cis-retinoic acid 1 mg/kg daily and radiotherapy 2.5 Gy daily. The treatment resulted in rapid improvement of the tumors with significant reduction of their size.

Follow-up may not be beneficial after treatment of grade 1 breast cancer.

BACKGROUND: Identification of women treated for breast cancer who have a low risk of locoregional recurrence or contralateral breast cancer, and who can be discharged safely from follow-up, would lower costs without compromising prognosis. This study investigated the risk of locoregional recurrence and contralateral breast cancer in women treated for grade 1 breast cancer. METHODS: Some 1143 women who had surgery for breast cancer were followed, and the rate of locoregional recurrence or contralateral breast cancer was determined. The risk was compared to the tumour grade. RESULTS: At a mean follow-up of 9.1 years, 10-year estimates of the cumulative risk of locoregional recurrence or contralateral breast cancer for grade 1, 2 and 3 breast cancer were 0.03 (95 per cent confidence interval (c.i.) 0.01 to 0.08), 0.12 (0.09 to 0.15) and 0.16 (0.13 to 0.20) respectively. Grade 1 tumours had a risk of locoregional recurrence or contralateral breast cancer of 285 (95 per cent c.i. 93 to 670) per 100,000 person-years. CONCLUSION: Women treated for grade 1 breast cancer could be discharged from follow-up after completion of the primary treatment, without compromising their quality of care.

Implication of bevacizumab in fatal arterial thromboembolic incidents.

Bevacizumab, a humanized monoclonal antibody against vascular endothelial factor (VEGF), is approved for the treatment of metastatic colon cancer, but it has also shown efficacy in first line therapy of non-squamous-cell non-smallcell lung cancer, breast cancer and clear-cell renal cancer. Antiangiogenic therapy severe toxic effects such as stroke, myocardial infraction, angina, arterial thromboembolism, pulmonary embolism or haemorrhage, gastrointestinal perforation, heart failure should be taken into account during treatment with bevacizumab. We describe and discuss two cases of cancer patients who developed fatal arterial thromboembolic episodes after administration of bevacizumab. Due to the recent launch of antiangiogenic agents and the limited experience with their use in clinical practice, their adverse effects and pharmacological toxicities, sometimes fatal, are not well-established and a detailed registration of them is needed.

Inhibition of rat hepatic CYP2E1 by quinacrine: molecular modeling investigation and effects on 4-(methyl nitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced mutagenicity.

Increased activity of CYP2E1 has been associated with increased risk of chemically-mediated cancers, through enhanced activation of a variety of procarcinogens. In this context, inhibition of CYP2E1 is potentially of significance in xenobiotic toxicity. The aim of the present study was to test the hypothesis that quinacrine inhibits hepatic CYP2E1. For this purpose, disulfiram (75 mg/kg i.p) as an inhibitor and isoniazid (100 mg/kg i.p) as an inducer of CYP2E1, as well as quinacrine (50 mg/kg i.p) were administered to Wistar rats and the hepatic activity of CYP2E1 was measured. The expression of CYP2E1 was further assessed by Western blot analysis. As expected, disulfiram inhibited, while isoniazid induced the activity and expression of the enzyme. Interestingly, treatment with quinacrine resulted in a significant decrease of CYP2E1 activity and expression. To investigate any similarities in the inhibition of CYP2E1 by quinacrine and disulfiram, molecular modeling techniques were adopted and revealed that quinacrine molecule anchors inside the same binding pocket of the protein where disulfiram is also attached. Finally, as assessed by the sister chromatid exchanges (SCE) assay, quinacrine was demonstrated to reduce the mutagenic effects of the tobacco-specific N-nitrosamine 4-(methyl nitrosamino)-1-(3-pyridyl)-1-butanone (NNK), which is known to be converted to active mutagen in the liver principally through CYP2E1. We suggest that these antimutagenic effects of quinacrine could be possibly attributed, at least in part, to its ability to block the bioactivation of NNK, mainly by the inhibition of CYP2E1. Our results, even preliminary, indicate that quinacrine as an inhibitor of CYP2E1 might be protective against chemically-induced toxicities such as NNK-induced mutagenicity.

Multiple cutaneous ecchymoses associated with the administration of bevacizumab.

Nowadays, the introduction of combinational therapies with biological agents against advanced or resistant to chemotherapy tumors or for the treatment of cancer patients with organ failures becomes more and more attractive. The authors describe the case of a 60-year-old female patient with a multi-refractory to conventional cytotoxic therapy laryngeal cancer that was treated with cetuximab and bevacizumab combination therapy. Bevacizumab administration was associated with appearance of multiple cutaneous ecchymoses. This is a first-time reported adverse effect. Due to the recent launch of these agents and the limited experience of their use in clinical practice, their adverse effects and pharmacological toxicities are not well established and call for their detailed registration and reporting.

Synchronous bilateral seminoma: report of a case and literature review.

Bilateral occurrence of a primary testicular tumor is unusual. The reported incidence of bilateral germ cell tumors of the testes has been between 0.5 and 7% and the majority of these cancers (90%) are metachronous. We report the case of a 27-year-old man with synchronous bilateral seminoma and discuss the value of the histopathological diagnosis in therapy and prognosis. The related literature is concisely reviewed.

Synergistic interaction between a mixed ligand copper (II) chelate complex and two anticancer agents in T47D human breast cancer cells in vitro.

PURPOSE: We have developed a copper(II) chelate complex with a tridentate ONN-Schiff ligand and the anion of salicylate, showing a potent cytotoxic activity against a panel of human and murine cancer cell lines. In this experiment we have explored the combination effect between Cu(SalNEt(2))salicylate (Cu-Sal) complex and two widely used drugs in cancer chemotherapy, bleomycin (BLM) and 5-fluorouracil (5-FU), against T47D human breast cancer cells. Previous theoretical quantum-chemical studies of this complex and ass adducts with biological molecules elucidated the underlying mechanism of action of this complex. MATERIALS AND METHODS: Cells grown in adherence in 96-well microplates were exposed simultaneously to both agents for 48 h. During cytotoxicity was assessed via the XTT colorimetric assay. The combined drug interaction was assessed with the median-effect analysis and the combination index (CI). RESULTS: Concurrent treatment of cells with Cu-Sal complex and the chemotherapeutic drugs BLM and 5-FU and the antioxidant agent ascorbic acid (AsA) resulted mainly in synergistic interaction for most concentration ratios. CONCLUSION: Cu-Sal complex interacts synergistically with the chemotherapeutic drugs for most schedules of administration. These findings call for prompting to search for possible interaction of this complex with other cellular elements of fundamental importance in cell proliferation.

Prevalence of autoantibodies (ANA, anti ds-DNA, ENA, IMF) and rheumatic syndromes in patients with lymphoproliferative diseases.

PURPOSE: In the development of rheumatic syndromes as well as of lymphoproliferative disorders it is probable that there are common genetic, environmental and immunoregulatory pathogenetic mechanisms. The purpose of this study was to determine the frequency of simultaneous presentation of both lymphoma or other lymphoproliferative diseases, and rheumatic syndromes. PATIENTS AND METHODS: In this study included were all patients with lymphoproliferative diseases (1920 patients) followed at our hospital during the last 5 years. 312/1920 (16.2%) patients presented with non-Hodgkin's lymphoma (NHL), 645/1920 (33.5%) had myeloma, 558/1920 (29%) had leukemia and miscellaneous other hematological malignancies (Hodgkin's lymphoma, cryoglogulinaemia etc) had 405/1920 patients (21%). Antinuclear antibodies (ANA), ribosome P and intermediate filament antibodies (IMF) were measured by immunofluorescence (IF). Anti-double-stranded DNA (ds-DNA) antibodies and extractable nuclear antigens (ENA: Sm, RNP, SSA, SSB, Scl70) were measured by ELISA and the rheumatoid factor (RF) by nephelometry. RESULTS: 388/1920 (4.6%) patients were ANA positive (antibody titres>1/160). On the other hand, clinical symptoms attributed autoimmune diseases (arthralgias, morning stiffness etc) plus autoantibodies other than ANA were present only in 8/312 (2.56%) patients with NHL, among them one with anti-cardiolipin antibodies. It is interesting that from these 8 patients, 3 had MALT lymphoma and 3 diffuse B-cell large cell lymphoma. Also, we detected anti-IMF and IgM and lgG anti-CMV antibodies in 2/312 (0.42%) patients with NHL. CONCLUSION: We conclude that the simultaneous presence of lymphoproliferative diseases and rheumatic syndromes are more frequent among lymphoma patients than in other lymphoproliferative diseases. Therefore, the screening of antibodies in NHL patients may be useful for the discovery and the treatment of an underlying autoimmune disease.

Octreotide neutralizes dexamethasone antitumor actions on P388 murine lymphocytic leukemia in vivo.

PURPOSE: A wide variety of human malignancies, including lymphoproliferative neoplasms, express somatistatin (SS) receptors (SS-R). SS induces apoptosis and exerts pronounced antiproliferative effects on various human tumors cell lines, human xenografts, and animal tumors including P388 lymphocytic leukemia. In patients with thymoma the combination of octreotide (OCT) with corticosteroids improves the overall response rate. It has been reported that SS can increase glucocorticoid activity. Hereby, we studied the in vitro and in vivo activity of the SS analogue OCT and of the glucocorticoid dexamethasone (DEX) alone or in combination against the murine P388 lymphocytic leukemia. MATERIALS AND METHODS: Cultures of P388 lymphocytic leukemia and BDF(1) male mice implanted with P388 cells where used for the in vitro an in vivo evaluation of the antileukemic activity of SS and DEX. RESULTS: OCT induced a moderate and DEX a satisfactory cytostatic effect in vitro. OCT produced borderline antileukemic effect when administered on days 1-5 while DEX was effective in all schemes and routes of administration. However, none of the combination schemes exerted any anti-leukemic activity both in vitro and in vivo. CONCLUSION: Since both SS and glucocorticoids exert direct (via receptors) and indirect antitumor actions (regulation of growth factor activity) on several cell lines, in vitro and in vivo, it becomes obvious that further in vitro studies shall provide the molecular evidence for the signal transduction pathways which are involved in the interactions of such important anticancer drugs. Based on the results of the present study, the simultaneous use of these drugs in clinical practice should be carefully considered.

Synergistic interaction between a novel mixed ligand copper(II) chelate complex and a panel of anticancer agents in T47D human breast cancer cells in vitro.

PURPOSE: We have developed a novel copper(II) chelate complex with a tridentate ONN-Schiff base ligand and the anion of salicylate, which presented a potent cytotoxic activity against a panel of human and murine cancer cell lines. In this experiment we explored the combined effect between Cu(SalNEt(2))salicylate (Cu-Sal) complex and the widely used anticancer drugs carboplatin (CBDCA), cyclophosphamide (CTX) and paclitaxel (TXL) against T47D human breast cancer cells. Theoretical (quantum-chemical) study of this complex and its adducts with biological molecules were carried out, aiming at the elucidation of the underlying mechanism of action. MATERIALS AND METHODS: Cells grown in adherence in 96-well microplates were exposed simultaneously to both agents for 48 h. Drug cytotoxicity was assessed via the XTT colorimetric assay. The combined drug interaction was assessed with the median-effect analysis and the combination index (CI). RESULTS: Copper(II) salicylate complex was proved active against T47D human breast cancer cells. Concurrent treatment of cells with Cu-Sal complex and the chemotherapeutic drugs CBDCA, CTX and TXL, mainly showed a synergistic interaction in most concentration ratios. CONCLUSION: Cu-Sal complex interacts synergistically with tested chemotherapeutic drugs for most schedules of administration, and only occasionally an additive or antagonistic effect was apparent. With the aid of quantum-chemical calculations it was demonstrated that the mechanism of action of this complex involves binding to DNA and RNA. These findings prompt to search for possible interaction of this complex with other cellular elements of fundamental importance in cell proliferation.

A preclinical survey on the efficacy of lactandrate in the treatment of colon carcinoma.

PURPOSE: There has been a recent and dramatic increase in the pace of drug development for colorectal cancer which holds promise to further improve curative therapy. We tested lactandrate, an alkylating ester of D-lactam androsterone, for antineoplastic activity against colon adenocarcinoma in vitro and in vivo. MATERIALS AND METHODS: The cytostatic and cytotoxic activity of lactandrate were evaluated in vitro against 9 human colon adenocarcinoma cell lines. The in vitro testing was performed with the sulforhodamine B (SRB) colorimetric assay and the mean concentrations of each drug that generated 50% (GI50) or total (100%) growth inhibition (TGI), as well as the drug concentrations that produced cytotoxicity against 50% of the cultured cells (IC50) were calculated. The in vivo antitumour effect was determined against two rodent colon carcinomas, the Colon 26 and the relatively chemoresistant Colon 38 carcinoma, as well as against the human xenograft CX-1 colon carcinoma. RESULTS: Lactandrate displayed a satisfactory activity against the 9 human colon cancer cell lines, inducing significant growth inhibition and cytotoxicity. Lactandrate induced antiproliferative activity against colon cancer cell lines linearly correlated with the carcinoembryonic antigen (CEA) production. There was a non-linear polynomial correlation between CEA production and the cytotoxic effect of lactandrate. The more differentiated cell lines DLD-1 and HCC2998 appeared more resistant to the cytostatic effect of lactandrate. In vivo, the compound produced a significant antitumour activity against Colon 26 and Colon 38, as well as a moderate antitumour effect against CX-1 colon carcinoma. CONCLUSION: Preclinical research supports the high in vitro and in vivo antitumour potential of lactandrate against colon carcinoma. Therefore, lactandrate represents an important candidate drug for further clinical development.

Antitumour effect of a- and d- lactam androgen nitrogen mustards on non-small cell lung carcinoma.

PURPOSE: We tested 3 alkylating esters of D-lactam androsterone, 3 alkylating esters of A-lactam testosterone and the alkylating nitrogen mustard components of these esters, for antineoplastic activity on non-small cell lung carcinoma (NSCLC) in vitro and in vivo. MATERIALS AND METHODS: Cytostatic and cytotoxic activity was evaluated in vitro against 10 human NSCLC cell lines. The in vitro testing was performed with the MTT metabolic-colorimetric assay and the mean concentrations of each drug that generated 50% or total (100%) growth inhibition (GI50 and TGI, respectively) as well as the drug concentrations that produced cytotoxicity against 50% of the cultured cells (IC50) were calculated. Furthermore, the in vivo antitumour effect was determined against the relatively chemo-resistant Lewis lung carcinoma (LLC) on mice. The acute toxicity of the tested compounds was appointed in C57BL mice and the antitumor effect on LLC was assessed from the percent increase in median lifespan of the treated animals over the untreated (control) (T/C%). RESULTS: The lactam steroidal esters presented lower toxicity and increased antineoplastic activity in vitro and in vivo compared to their respective alkylating components. An A-lactam testosterone ester namely: 17beta-hydroxy- 3-aza-A-homo-4alpha-androsten-4-one-p-N,N-bis (2chloroethyl) amino phenoxy acetate (ALT-CAPOA) performed significantly higher anticancer activity in vitro and in vivo. This compound generated 37.5% 90-day disease free survivors (cures) against LLC. CONCLUSION: These results indicate a high antitumor potential of lactam steroid alkylating esters depended on the alkylating moiety as well as on the modified steroidal carrier. Preclinical research supports that ALT-CAPOA generates well-tolerated toxicity as well as superior antitumor activity against NSCLC. These significant results call for further clinical development.

Cytotoxic effects of a mixed ligand copper(II) chelate complex against a panel of human and murine cancer cells in vitro. Theoretical study of the mechanism of biologic action through molecular modelling.

PURPOSE: In an effort to discover new compounds with anticancer activity, we have developed a novel copper (II) [Cu(II)] chelate complex with a tridentate ONNSchiff base ligand and the anion of salicylate and we evaluated the in vitro chemosensitivity of various human and murine tumor cell lines by measuring cell growth inhibition. The ultimate goal was to evaluate the existence of a potential antitumor activity of this complex. Beyond the cytotoxic activity assessment of the complex, we aimed at the elucidation of the underlying mechanism of action of this complex and its interactions with biological molecules, carrying out theoretical (quantum-chemical) calculations. MATERIALS AND METHODS: Cells grown in adherence or in suspension in 96-well microplates were exposed to Cu(II) complex for 24, 48 or 72 h. In vitro drug cytotoxicity was assessed by SRB and XTT colorimetric assays. Molecular modelling tools were used applying semiempirical and ab initio calculations. RESULTS: A series of experiments was carried out, showing a potent cytotoxic activity against most of the tested cancer cell lines. Quantum-chemical calculations demonstrate that the mechanism of the cellular damage can be explained, at least in part, by the ability of the nucleobases and nucleotides to be subject to nucleophilic attack on copper. CONCLUSION: Profound growth inhibitory effects were observed for the tested Cu(II) complex. It was also verified the hypothesis that the mechanism of action of this complex involves binding to DNA and RNA. These findings prompt to search for possible interaction of this complex with other cellular elements of fundamental importance for cell proliferation.

Preclinical evaluation of the homo-aza-steroid ester 13beta-hydroxy-13alpha-amino-13,17- seco-5alpha-androstan-17-oic-13,17-lactam-p-bis(2-chloroethyl)aminophenoxy acetate for the treatment of malignant melanoma.

PURPOSE: To investigate the in vitro and in vivo activity of an homo-aza-steroid alkylating ester, namely 13beta-hydroxy- 13alpha-amino-13,17-seco-5alpha-androstan-17-oic-13,17- lactam-p-bis (2-chloro ethyl) aminophenoxy acetate (HASE), in comparison with dacarbazine (DTIC) in the treatment of malignant melanoma. MATERIALS AND METHODS: Cytotoxicity was assessed in vitro by the MTT assay using a panel of 6 malignant melanoma human cell lines, with or without the presence of rat liver microsome assay. B16 melanoma-bearing mice were used to evaluate in vivo the antitumor activity of the tested compounds. RESULTS: In all cases of in vitro screening, HASE displayed significantly higher (p <0.0001) cytostatic and cytotoxic activity than DTIC. Moreover, the antitumor activity of HASE in B16 melanoma-bearing mice was satisfactory, prolonging the mice lifespan at 67%, compared to 43% achieved by DTIC. Furthermore, HASE significantly inhibited the tumor growth (tumor growth rate: <42%) as this was defined by tumor volume and weight differences, presenting higher antitumor effect than DTIC. CONCLUSION: HASE displayed superior in vitro and in vivo activity than DTIC in the treatment of melanoma. Thus, HASE may be considered as a significant candidate anticancer agent for further development.

Clonal chromosome rearrangements in hairy cell leukemia: personal experience and review of literature.

Cytogenetic studies in hairy cell leukemia (HCL) are rare. In the present report, cytogenetic investigations were performed on marrow cells obtained from 21 HCL male patients with a mean age of 57 years and active disease. Karyotypic analysis was successful in 18 of the 21 patients, either at diagnosis or in relapse after treatment with IFNa. Clonal chromosome abnormalities were detected in eight of 18 cases. The chromosome most frequently involved in the rearranged karyotypes was chromosome 14. Results are discussed with respect to 79 abnormal HCL cases obtained from an extensive review of the literature from 1978 to 2000.