Lucely Cetina

Epigenetics of cervical cancer. An overview and therapeutic perspectives

Cervical cancer remains one of the greatest killers of women worldwide. It is difficult to foresee a dramatic increase in cure rate even with the most optimal combination of cytotoxic drugs, surgery, and radiation; therefore, testing of molecular targeted therapies against this malignancy is highly desirable. A number of epigenetic alterations occur during all stages of cervical carcinogenesis in both human papillomavirus and host cellular genomes, which include global DNA hypomethylation, hypermetylation of key tumor suppressor genes, and histone modifications. The reversible nature of epigenetic changes constitutes a target for transcriptional therapies, namely DNA methylation and histone deacetylase inhibitors. To date, studies in patients with cervical cancer have demonstrated the feasibility of reactivating the expression of hypermethylated and silenced tumor suppressor genes as well as the hyperacetylating and inhibitory effect upon histone deacetylase activity in tumor tissues after treatment with demethylating and histone deacetylase inhibitors. In addition, detection of epigenetic changes in cytological smears, serum DNA, and peripheral blood are of potential interest for development of novel biomolecular markers for early detection, prediction of response, and prognosis.

Histone acetylation and histone deacetylase activity of magnesium valproate in tumor and peripheral blood of patients with cervical cancer. A phase I study

BackgroundThe development of cancer has been associated with epigenetic alterations such as aberrant histone deacetylase (HDAC) activity. It was recently reported that valproic acid is an effective inhibitor of histone deacetylases and as such induces tumor cell differentiation, apoptosis, or growth arrest.MethodsTwelve newly diagnosed patients with cervical cancer were treated with magnesium valproate after a baseline tumor biopsy and blood sampling at the following dose levels (four patients each): 20 mg/kg; 30 mg/kg, or 40 mg/kg for 5 days via oral route. At day 6, tumor and blood sampling were repeated and the study protocol ended. Tumor acetylation of H3 and H4 histones and HDAC activity were evaluated by Western blot and colorimetric HDAC assay respectively. Blood levels of valproic acid were determined at day 6 once the steady-state was reached. Toxicity of treatment was evaluated at the end of study period.ResultsAll patients completed the study medication. Mean daily dose for all patients was 1,890 mg. Corresponding means for the doses 20-, 30-, and 40-mg/kg were 1245, 2000, and 2425 mg, respectively. Depressed level of consciousness grade 2 was registered in nine patients. Ten patients were evaluated for H3 and H4 acetylation and HDAC activity. After treatment, we observed hyperacetylation of H3 and H4 in the tumors of nine and seven patients, respectively, whereas six patients demonstrated hyperacetylation of both histones. Serum levels of valproic acid ranged from 73.6–170.49 μg/mL. Tumor deacetylase activity decreased in eight patients (80%), whereas two had either no change or a mild increase. There was a statistically significant difference between pre and post-treatment values of HDAC activity (mean, 0.36 vs. 0.21, two-tailed t test p < 0.0264). There was no correlation between H3 and H4 tumor hyperacetylation with serum levels of valproic acid.ConclusionMagnesium valproate at a dose between 20 and 40 mg/kg inhibits deacetylase activity and hyperacetylates histones in tumor tissues.

Modern management of locally advanced cervical carcinoma

Radiation was until recently the key and only modality for the routine treatment of locally advanced cervical carcinoma. However after years of studying multi-modality treatments as an alternative to radiation alone in randomized phase III trials, the standard treatment has changed to chemo-radiation based on cisplatin. Three recent meta-analyses have confirmed that cisplatin-based chemo-radiation adds an absolute 12% benefit in five-year survival over radiation therapy alone. Neoadjuvant chemotherapy followed by radiation has not been of proven benefit, but when neoadjuvant chemotherapy is followed by surgery, an absolute increase of 15% in five-year survival over radiation alone is seen. This benefit in survival is comparable to that obtained with the current chemo-radiation schedules based on cisplatin. Despite these encouraging results there remains room for improvement as the five-year survival of patients treated with chemo-radiation ranges from nearly 80% in bulky IB tumours to only 25% in stage IVA disease. Other therapeutic approaches need to be fully evaluated including the use of chemo-radiation after neoadjuvant chemotherapy; the use of new drug combinations and the multi-modality combination of neoadjuvant chemotherapy followed by radical surgery plus adjuvant chemo-radiation. Likewise, the addition of radiosensitizers to cisplatin, preoperative chemo-radiation and/or adjuvant chemotherapy may eventually improve the currents results of cisplatin-based chemo-radiation. Nevertheless, it is hard to foresee a dramatic increase in cure rate, even with the most optimal combination of cytotoxic drugs, surgery and radiation, and thus the testing of molecular targeted therapies against cervical cancer is a logical step to follow.

Radiosensitizers in cervical cancer. Cisplatin and beyond

Cervical cancer continues to be a significant health burden worldwide. Globally, the majority of cancers are locally advanced at diagnosis; hence, radiation remains the most frequently used therapeutical modality. Currently, the value of adding cisplatin or cisplatin-based chemotherapy to radiation for treatment of locally advanced cervical cancer is strongly supported by randomized studies and meta-analyses. Nevertheless, despite these significant achievements, therapeutic results are far from optimal; thus, novel therapies need to be assayed. A strategy currently being investigated is the use of newer radiosensitizers alone or in combination with platinum compounds. In the present work, we present preclinical information on known and newer cytotoxic agents as radiosensitizers on cervical cancer models, as well as the clinical information emanating from early phase trials that incorporate them to the cervical cancer management. In addition, we present the perspectives on the combined approach of radiation therapy and molecular target-based drugs with proven radiosensitizing capacity.

Human Papillomavirus (HPV) in breast tumors: prevalence in a group of Mexican patients

BackgroundBreast cancer is one of the main health problems in developed countries, occupying first place in mortality in women. It is well-known that there are risk factors associated with breast cancer development. Nonetheless, in 50–80% of cases known risk factors have not been identified, this has generated the attempt to identify new factors related with this neoplasia as viral infections. The aim of this work is investigate the prevalence of HPV DNA in patients with breast lesions at the Instituto Nacional de Cancerologia de Mexico.MethodsFifty-one cases of breast cancer were selected from the files of the institute and compared by age and tumor size with 43 cases of non malignant breast lesions (fibroadenoma, fibrocystic disease and phyllodes tumor). Paraffin embedded specimens were selected, HPV DNA was analyzed by polymerase chain reaction (PCR) and sequenced for different types of HPV in case of positivity for HPV-DNA. Descriptive analysis of clinical and pathological variables was performed and comparisons between positive and negative cases was done.ResultsAll patients were mexican, mean age was 53.3, median age of menarche was 13 and median tumor size 9 cms. Cervicovaginal cytology was performed to all patients, 1 patient (1.9%) of cancer group had HPV and none in the other group, no cases were diagnosed with cervical dysplasia. In the group of carcinomas 36 (70.5%) were negative and 15 (29.4%) were positive to HPV-DNA, 10(66.6%) were positive for HPV 16, 3(20%) for HPV 18, two cases (13.4%) were positive for both. In the group of benign conditions all were negative to HPV-DNA.ConclusionPresence of HPV in breast cancer in our group of cases is high in comparison to other authors; larger numbers of cases need to be analyzed in order to establish the exact role of this virus in the pathogenesis of breast cancer.

Routine management of locally advanced cervical cancer with concurrent radiation and cisplatin. Five-year results

BackgroundGlobally, cervical cancer primarily affects socially disadvantaged women. Five randomized trials were the foundation for adopting cisplatin-based chemotherapy during radiation as the standard of care for high-risk patients after primary radical hysterectomy who require adjuvant radiation and for locally advanced patients treated with definitive radiation. These results were obtained in clinical trials performed in carefully prepared academic centers; hence, we sought to determine whether these results could be reproduced when patients were treated on an out-of-protocol basis.MethodsWe reviewed the files of 294 patients with locally advanced cervical cancer who received radiation plus weekly cisplatin as routine management between 1999 to 2003, and analyzed treatment compliance, response rate, toxicity, and survival.ResultsA total of 294 patients who received radiation and cisplatin were analyzed. Mean age was 43.8 years (range, 26–68 years). The majority of cases were squamous cell carcinoma (87.8%), and distribution according to International Federation of Gynecology and Obstetrics (FIGO) stage was as follows: IB2-IIA, 23%; IIB, 53.3%, and IIIB, 23%; there were only two IVA cases. Overall, 96% of patients completed external beam, and intracavitary therapy. The majority of patients (67%) received the planned six courses of weekly cisplatin. Complete responses were achieved in 243 (83%) patients, whereas 51 (17%) had either persistent (32 patients, 10.8%) or progressive (19 patients, 6.4%) disease. At median follow-up (28 months; range, 2–68 months), 36 patients (12.2%) have relapsed (locally 30.5, and systemically, 69.5%). The most common toxicities were hematologic and gastrointestinal, in the majority of cases considered mild-moderate. At median follow-up (28 months; range, 2–68 months), overall and progression-free survival are 76.5 and 67%, respectively.ConclusionOur results support use of chemoradiation with six weekly applications of cisplatin at 40 mg/m2 during external radiation for routine management of locally advanced cervical cancer.

Brachytherapy versus radical hysterectomy after external beam chemoradiation with gemcitabine plus cisplatin: a randomized, phase III study in IB2–IIB cervical cancer patients

BACKGROUND The aim of the present study was to demonstrate that radical hysterectomy (RH) leads to improved survival outcomes in FIGO stage IB2-IIB cervical cancer when compared with standard brachytherapy (BCT) after identical external beam chemoradiation (EBRT-CT). PATIENTS AND METHODS EBRT-CT treatment consisted of six courses of cisplatin at 40 mg/m² and gemcitabine at 125 mg/m² per week concurrent with 50.4 Gy of radiation. In the BCT arm, EBRT-CT was followed by BCT to reach a point A dose of 85 Gy, whereas in the experimental arm, a type III RH with bilateral pelvic lymph node dissection and para-aortic lymph node sampling (RH) was carried out within 4-6 weeks after EBRT-CT. RESULTS Between May 2004 and June 2009, 211 patients were enrolled (BCT, 100 and RH, 111). At a median follow-up time of 36 months (3-80), progression-free survival (PFS) and overall survival (OS) rates were similar in both the arms. PFS rates were 74.8% and 71.7% in the BCT and RH arms [HR 0.6516 (95% confidence interval (CI) 0.3504-1.2116)], P = 0.186. OS rates were 76.3% in the BCT versus 74.5% in the surgical arm [HR 0.6981 (95% CI 0.3106-1.3439)], P = 0.236. No differences were observed in the pattern of local and systemic failures. CONCLUSIONS This study failed to demonstrate that RH after EBRT-CT is superior to standard BCT.

A PHASE I study of carboplatin concurrent with radiation in FIGO stage IIIB cervix uteri carcinoma

PURPOSE Chemoradiation based on cisplatin, most commonly weekly, is the standard treatment of locally advanced cervical cancer; however, the nephrotoxic potential and the requirement for hydration of cisplatin somewhat restrains its use. The objective of this study was to determine the recommended dose of carboplatin when administered weekly during pelvic radiation (RT). METHODS AND MATERIALS Twenty-four histologically proven, International Federation of Gynecology and Obstetrics Stage IIIB patients were treated with standard pelvic RT concurrently with six weekly applications of carboplatin at the following dose levels: 100 mg/m(2), 116 mg/m(2), 133 mg/m(2), and 150 mg/m(2). Six patients per level were treated. Acute toxicity was assessed according to the Radiation Therapy Oncology Group Acute Radiation Morbidity Scoring Criteria. The recommended dose was defined as the one that was one level below the level at which dose-limiting toxicity was present in more than one-third of patients. RESULTS Between September 2001 and July 2002, 24 patients were accrued. All but two completed external beam radiotherapy and intracavitary treatment. The treatment was well tolerated. The median number of weekly applications of carboplatin was six, and the mean dose to points A and B was 85.6 Gy (range 75.2-91.6) and 62.9 Gy (range 58.2-74.6), respectively. RT was delivered within 41.7 days (range 33-70). Dose-limiting toxicity (leukopenia and/or neutropenia) was present in 50% of patients treated at the higher dose level (150 mg/m(2)). At the recommended dose of 133 mg/m(2), 33% of patients presented with Grade 3 leukopenia. At treatment completion, 75% of patients had a complete clinical response. CONCLUSION Carboplatin at 133 mg/m(2), weekly for 6 weeks, is a well tolerated and effective radiosensitizer in cervical cancer patients.

Prognostic significance of pathological response after neoadjuvant chemotherapy or chemoradiation for locally advanced cervical carcinoma

BackgroundCisplatin-based chemoradiation is the standard of care for locally advanced cervical cancer patients; however, neoadjuvant modalities are currently being tested. Neoadjuvant studies in several tumor types have underscored the prognostic significance of pathological response for survival; however there is a paucity of studies in cervical cancer investigating this issue.MethodsFour cohorts of patients with locally advanced cervical carcinoma (stages IB2-IIIB); included prospectively in phase II protocols of either neoadjuvant chemotherapy with 1) cisplatin-gemcitabine, 2) oxaliplatin-gemcitabine, 3) carboplatin-paclitaxel or 4) chemoradiation with cisplatin or cisplatin-gemcitabine followed by radical hysterectomy were analyzed for pathological response and survival.ResultsOne-hundred and fifty three (86%) of the 178 patients treated within these trials, underwent radical hysterectomy and were analyzed. Overall, the mean age was 44.7 and almost two-thirds were FIGO stage IIB. Pathological response rates were as follows: Complete (pCR) in 60 cases (39.2%), Near-complete (p-Near-CR) in 24 (15.6 %) and partial (pPR) in 69 cases (45.1%). A higher proportion rate of pCR was observed in patients treated with chemoradiotherapy (with cisplatin [19/40, 47.5%]; or with cisplatin-gemcitabine [24/41, 58.5%] compared with patients receiving only chemotherapy, 6/23 (26%), 3/8 (37.5%) and 8/41 (19.5%) for cisplatin-gemcitabine, oxaliplatin-gemcitabine and carboplatin-paclitaxel respectively [p = 0.0001]). A total of 29 relapses (18.9%) were documented. The pathological response was the only factor influencing on relapse, since only 4/60 (6.6%) patients with pCR relapsed, compared with 25/93 (26.8%) patients with viable tumor, either pNear-CR or pPR (p = 0.001). Overall survival was 98.3% in patients with pCR versus 83% for patients with either pNear-CR or pPR (p = 0.009).ConclusionComplete pathological response but no Near-complete and partial responses is associated with longer survival in cervical cancer patients treated with neoadjuvant chemotherapy or chemoradiotherapy.

Hydralazine–valproate: a repositioned drug combination for the epigenetic therapy of cancer

Introduction: DNA methylation (DNMTi) and histone deacetylase inhibitors (HDACi) are in development for cancer therapy. So far, four epigenetic drugs are approved for myelodysplastic syndrome (MDS) and cutaneous T-cell lymphoma (CTCL). The combination of hydralazine-valproate (TRANSKRIP™) is being repositioned as an oral DNMT and HDAC inhibitor. Areas covered: Brief discussion on the current status of epigenetic drugs and studies published on the preclinical and clinical development of the hydralazine-valproate combination. Expert opinion: Drug repositioning is a strategy for prompt and cost-efficient drug discovery. There is evidence that combining DNMTi with HDACi would be more efficacious than administering each agent on its own. Hydralazine-valproate is safe when used alone or in combination with chemotherapy or chemoradiation. The fact that both drugs are orally administered is another advantage over current epigenetic drugs. This combination is promising but larger studies are needed. Among these, the randomized Phase III trials in advanced and in locally advanced cervical cancer combined with chemotherapy and cisplatin-radiation respectively, would eventually confirm its efficacy. Studies on MDS and CTCL would also eventually prove the efficacy of hydralazine valproate so that in the coming years hydralazine-valproate could have a role in cancer epigenetic therapy.