Effect of cisplatin on the clinically relevant radiosensitivity of human cervical carcinoma cell lines

Concurrent chemotherapy with high-dose rate brachytherapy after treatment with chemoradiotherapy in cases of locally advanced carcinoma cervix: A study from rural area of Maharashtra, India

Aim

This study aims to evaluate the efficacy, feasibility, tolerability, and toxicity of concurrent chemotherapy and brachytherapy for locally advanced cervical carcinoma.

Materials and Methods

Forty patients of cervical carcinoma were included in this study. The study period ranges from October 2016 to September 2019. Patients were evaluated and treated as per the protocol: external beam radiotherapy (50 Gy in 25 fractions) and concurrent weekly chemotherapy with injection (Inj.) cisplatin (30 mg/m2) followed by high-dose rate brachytherapy (3 fractions of 7 Gy each) and concurrent chemotherapy Inj. cisplatin (30 mg/m2).

Results

Out of 40 patients enrolled in the study, 36 patients completed the treatment (17 Stage II and 19 Stage III). The incidence of Grade I and II skin toxicities were 78% and 10%, respectively. The incidence of genitourinary toxicities with respect to Grade I and II were 72% and 12%, respectively. There were Grade III hematological toxicities in two patients and the brachytherapy treatment was delayed for 4-6 days. The overall complete response was found in 28 (78%) patients, partial response in six (16.7%) patients, and progressive disease in two (5.6%) patients at 3 months of follow-up. On the last follow-up, 21 (58%) patients were disease-free and there was disease failure in seven patients (5 local recurrence and 2 with distant metastasis).

Conclusion

Brachytherapy with the addition of concurrent chemotherapy is effective and feasible with acceptable toxicity for advanced stages of carcinoma cervix. This study upholds an interesting approach that can be regarded as feasible and tolerable for cervical cancer patients.

SERPINB3 (SCCA1) inhibits cathepsin L and lysoptosis, protecting cervical cancer cells from chemoradiation

The endogenous lysosomal cysteine protease inhibitor SERPINB3 (squamous cell carcinoma antigen 1, SCCA1) is elevated in patients with cervical cancer and other malignancies. High serum SERPINB3 is prognostic for recurrence and death following chemoradiation therapy. Cervical cancer cells genetically lacking SERPINB3 are more sensitive to ionizing radiation (IR), suggesting this protease inhibitor plays a role in therapeutic response. Here we demonstrate that SERPINB3-deficient cells have enhanced sensitivity to IR-induced cell death. Knock out of SERPINB3 sensitizes cells to a greater extent than cisplatin, the current standard of care. IR in SERPINB3 deficient cervical carcinoma cells induces predominantly necrotic cell death, with biochemical and cellular features of lysoptosis. Rescue with wild-type SERPINB3 or a reactive site loop mutant indicates that protease inhibitory activity is required to protect cervical tumor cells from radiation-induced death. Transcriptomics analysis of primary cervix tumor samples and genetic knock out demonstrates a role for the lysosomal protease cathepsin L in radiation-induced cell death in SERPINB3 knock-out cells. These data support targeting of SERPINB3 and lysoptosis to treat radioresistant cervical cancers.

Wang et al. demonstrate the cytoprotective role of SERPINB3 against radiation-induced necrosis, showing that cells lacking SERPINB3 protein both in culture and in mice are more sensitive to radiation and cisplatin-induced cell death. The authors also report that the cell death induced by radiation in SERPINB3-lacking cells is lysoptosis and implicate the lysosomal protease cathepsin L in this process.

Evaluation of tumor response three months after concomitant chemoradiotherapy with high dose rate brachytherapy as a definitive treatment modality for locally advanced cervical cancer

OBJECTIVE

Radiotherapy remains an essential part of the management of locally advanced cervical cancer. Post-treatment surveillance allows for tumor response assessment and early detection of progressive prosecutions or local recurrences that may benefit from salvage treatment. The objective of this work is to assess the effectiveness of this therapeutic modality.

MATERIALS METHODS

This is a retrospective study of 69 patients treated with concomitant radiation chemotherapy followed by high dose rate intracavitary brachytherapy. The tumor response was assessed by gynecologic physical examination at three months after the end of treatment.

RESULTS

Median age of patients is 54.9 years (33-78 years). The most common histological type is squamous cell carcinoma (89.9%). The average dose received during external radiotherapy is 52.2Gy (46-60Gy). The average dose received during brachytherapy is 27.5Gy (18-28Gy). Three months after completion of treatment, 95.6% of patients had complete tumor remission, and only 4.4% had a tumor residue of 1cm.

CONCLUSION

Radiation chemotherapy with brachytherapy allows for improved short-term local control in cervical cancer.

Significance of concurrent use of weekly cisplatin in carbon-ion radiotherapy for locally advanced adenocarcinoma of the uterine cervix: A propensity score-matched analysis

BACKGROUND

Although carbon-ion radiotherapy (C-ion RT) with concurrent chemotherapy (chemo-C-ion RT) is a promising treatment for adenocarcinoma (AC) of the uterine cervix, its long-term efficacy remains unclear. We evaluated the long-term significance of concurrent weekly cisplatin and C-ion RT for locally advanced AC of the uterine cervix.

METHODS

We performed a pooled analysis of patients with stage IIB-IVA AC of the uterine cervix who underwent C-ion RT alone or chemo-C-ion RT between September 2007 and December 2018 at our institution. Patients received 74.4 Gy (relative biological effectiveness) with or without cisplatin (40 mg/m² per week for up to 5 weeks), underwent no prior pelvic RT or systemic therapy, and had a performance status of 0-2. Propensity score matching was based on the year of diagnosis, regional lymph node metastasis, and stage.

RESULTS

The matched cohort contained 26 patients who underwent C-ion RT and 26 who underwent chemo-C-ion RT. The median age and follow-up period were 57 (range, 28-79) years and 34 (range, 2-126) months, respectively. The 5-year overall survival rate was significantly better in the chemo-C-ion RT group (72%) than in the C-ion RT group (46%; P = .041). The 5-year distant metastatic-free rate was also significantly better in the chemo-C-ion RT group (66%) than in the C-ion RT group (41%; P = .048). The incidence of grade ≥ 3 late toxicities was comparable between the two groups.

CONCLUSIONS

Chemo-C-ion RT for locally advanced AC of the uterine cervix is associated with a long-term survival benefit.

Studying the regression profiles of cervical tumours during radiotherapy treatment using a patient-specific multiscale model

Apart from offering insight into the biomechanisms involved in cancer, many recent mathematical modeling efforts aspire to the ultimate goal of clinical translation, wherein models are designed to be used in the future as clinical decision support systems in the patient-individualized context. Most significant challenges are the integration of multiscale biodata and the patient-specific model parameterization. A central aim of this study was the design of a clinically-relevant parameterization methodology for a patient-specific computational model of cervical cancer response to radiotherapy treatment with concomitant cisplatin, built around a tumour features-based search of the parameter space. Additionally, a methodological framework for the predictive use of the model was designed, including a scoring method to quantitatively reflect the similarity and bilateral predictive ability of any two tumours in terms of their regression profile. The methodology was applied to the datasets of eight patients. Tumour scenarios in accordance with the available longitudinal data have been determined. Predictive investigations identified three patient cases, anyone of which can be used to predict the volumetric evolution throughout therapy of the tumours of the other two with very good results. Our observations show that the presented approach is promising in quantifiably differentiating tumours with distinct regression profiles.

Chemotherapy and molecular therapy in cervical cancer

In recent years, the treatment of locally-advanced and metastatic cervical cancer has improved greatly due to the introduction of targeted therapies, new chemotherapy combinations, and emerging treatments. Candidates for potentially curative treatment are those patients with good functional status without associated comorbidities. Numerous trials have demonstrated that chemotherapy prolongs survival versus supportive care alone. In addition, polychemotherapy schemes are superior to single agent regimens. Targeted molecular agents have proven beneficial in the treatment of cervical cancer. Second-line treatment should be considered standard practice in patients with good functional status. Finally, given the poor survival outcomes in patients with metastatic disease, participation in clinical studies should always be considered the best option.

Local Radiotherapy Affects Drug Pharmacokinetics-Exploration of a Neglected but Significant Uncertainty of Cancer Therapy

Purpose:

Concurrent chemoradiation therapy is the mainstay of treatment for many types of malignancies. However, concurrent chemoradiation therapy is associated with a greater number of systemic adverse effects than radiotherapy or chemotherapy alone.

Summary:

Pharmacokinetics is the study of a drug and/or its metabolite kinetics in the body, including absorption, distribution, metabolism, and elimination. The incidences of adverse effects are markedly higher in patients who receive concurrent chemoradiation therapy than in those who receive either radiotherapy or chemotherapy alone. This phenomenon implies that irradiation affects the pharmacokinetics of cytotoxic agents, namely the radiotherapy–pharmacokinetic phenomenon. Experimental animal studies have shown that local irradiation affects the systemic pharmacokinetics of 5-fluorouracil and cisplatin at both low dose (simulating generous dose distributed to normal tissues) and daily practice dose (mimicking therapeutic dose to target volumes). These effects are significant in the circulation of blood and lymphatic system as well as in the hepatobiliary excretion. Furthermore, recent studies have demonstrated that matrix metalloproteinase-8 plays an important role in the radiotherapy–pharmacokinetic phenomenon.

Conclusion:

In the present review, we provide a general overview of the radiotherapy–pharmacokinetic phenomenon and discuss the possible mechanisms governing the phenomenon.

Mitotic catastrophe is a putative mechanism underlying the weak correlation between sensitivity to carbon ions and cisplatin

In cancer therapy today, carbon ion radiotherapy is used mainly as monotherapy, whereas cisplatin is used concomitantly with X-ray radiotherapy. The effectiveness of concomitant carbon ions and cisplatin is unclear. To obtain the information on the mechanisms potentially shared between carbon ions or X-rays and cisplatin, we assessed the correlation of sensitivity to the single treatments. In 20 human cancer cell lines, sensitivity to X-rays strongly correlated with sensitivity to cisplatin, indicating the presence of potentially shared target mechanisms. Interestingly, the correlation of sensitivity to carbon ions and cisplatin was much weaker than that of sensitivity to X-rays and cisplatin, indicating the presence of potentially different target mechanisms between carbon ions and cisplatin. Assessment of clonogenic cell death by 4′,6-diamidino-2-phenylindole dihydrochloride staining showed that mitotic catastrophe was more efficiently induced by carbon ions than by the same physical dose of X-rays, while apoptosis and senescence were not. These data indicate that the correlation of sensitivity to carbon ions and cisplatin is weaker than that of sensitivity to X-rays and cisplatin, which are helpful as biological basis to understand the potentially shared mechanism among these treatments. Further investigation is mandatory to elucidate the clinical efficacy of carbon ions and cisplatin combination.

Radiotherapy for Hepatocellular Carcinoma: New Indications and Directions for Future Study

Hepatocellular carcinoma (HCC) is a leading cause of cancer death worldwide; its incidence is increasing in the United States. Depending on disease extent and underlying liver status, patients may be treated with local, locoregional, and/or systemic therapy. Recent data indicates that radiotherapy (RT) can play a meaningful role in the management of HCC. Here, we review published experiences using RT for HCC, including the use of radiosensitizers and stereotactic RT. We discuss methods for performing preclinical studies of RT for HCC and biomarkers of response. As a part of the HCC Working Group, an informal committee of the National Cancer Institute's Radiation Research Program, we suggest how RT should be implemented in the management of HCC and identify future directions for the study of RT in HCC.

The efficacy of concurrent cisplatin and 5-flurouracil chemotherapy and radiation therapy for locally advanced cancer of the uterine cervix

OBJECTIVE

To evaluate the efficacy of concurrent chemoradiation (CCRT) using 5-flurouracil (5-FU) and cisplatin for locally advanced cervical cancer.

METHODS

We reviewed the medical records of 57 patients with locally advanced cervical cancer (stage IIB-IVA and bulky IB2-IIA tumor) who underwent the CCRT at Dong-A University Hospital from January 1997 to June 2007. The CCRT consisted of 5-FU, cisplatin and pelvic radiation. Every three weeks, 75 mg/m(2) cisplatin was administered on the first day of each cycle and 5-FU was infused at the dose of 1,000 mg/m(2)/d from the second day to the fifth day of each cycle. Radiation was administered to the pelvis at a daily dose of 1.8 Gy for five days per week until a medium accumulated dose reached to 50.4 Gy. If necessary, the radiation field was extended to include paraaortic lymph nodes. Consolidation chemotherapy was performed using 5-FU and cisplatin.

RESULTS

Fifty-seven patients were enrolled and the median follow-up duration was 53 months (range 7-120 months). The overall response rate was 91.5% (74% complete response and 17.5% partial response). The 5-year overall survival and 3-year progression free survival rates were 69.4% and 74.9%, respectively. During the follow-up period (median 23 months, range 7-60 months), fourteen patients were diagnosed as recurrent disease.

CONCLUSION

CCRT with 5-FU and cisplatin which is the primary treatment for patients with locally advanced cervical cancer was effective and well tolerated.

Concomitant chemobrachyradiotherapy with ifosfamide and cisplatin followed by consolidation chemotherapy for women with locally advanced carcinoma of the uterine cervix--final results of a prospective phase II-study

OBJECTIVES

To evaluate the efficacy and toxicity of ifosfamide and cisplatin administered concomitantly with low-dose rate brachyradiotherapy followed by consolidation chemotherapy in the treatment of locally advanced squamous cell carcinoma (LASCC) or adeno/adenosquamous carcinoma of the uterine cervix.

METHODS

Sixty-two patients with primary uterine cervical cancer were enrolled between August 1999 and November 2004. The patients had to have FIGO-stage IB2 bulky to IVA disease, biopsy-proven squamous cell or adeno/adenosquamous carcinoma of the uterine cervix. The patients were to receive external radiotherapy (50 Gy in 25 fractions); ifosfamide 2 g/m2 plus cisplatin 75 mg/m2 was applied concomitantly during two low-dose rate brachyradiotherapy applications; the planned dose to point A was 85 Gy in total. After the completion of radiotherapy, i.e. external and concomitant chemobrachyradiotherapy, four cycles of consolidation chemotherapy with the same drug combination were to be administered.

RESULTS

The clinical complete response rate according to WHO-classification (assessed after the completion of the whole treatment procedures by gynecologic and radiologic evaluation and cervical biopsy) was 100%. After a median follow-up of 49 months (range 11-74 months), the recurrence-free and overall survival rates were 88.7%, respectively. The most frequent early toxicities were grade 3 and 4 leukopenias occurring in 25% and 11% of the cycles, respectively. Major delayed local complications occurred in 10 patients (16.1%).

CONCLUSION

These results indicate that concomitant chemobrachyradiotherapy with ifosfamide and cisplatin followed by consolidation chemotherapy with the same drug combination is a highly efficacious and very promising treatment protocol for patients with locally advanced LASCC or adeno/adenosquamous carcinoma of the uterine cervix.

Analysis of the in vitro synergistic effect of 5-fluorouracil and cisplatin on cervical carcinoma cells

5-Fluorouracil (5-FU) is currently being used as an anticancer drug to reduce tumor bulk in order to increase the operability rate and postoperative survival in patients with cervical cancer, which has been combined with cisplatin (CP) because of its superior activities observed in human carcinoma cells. However, the combined anticancer effect of 5-FU and CP in cervical carcinoma cells is poorly understood. Therefore, we conducted a study to investigate whether anticancer drugs 5-FU and CP may exhibit the combined antiproliferative effect in cervical carcinoma cells. Using proteomics analysis, including two-dimensional gel electrophoresis and matrix assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS), we investigated the antiproliferative effect-related proteins after treatment with 5-FU and/or CP. Our experiments showed that the combination of 5-FU and CP engaged both the apoptotic pathways: the membrane death receptor-mediated apoptosis pathway and the mitochondrial apoptotic pathway. Moreover, the combination of 5-FU and CP resulted in remarkable increasing susceptibility to apoptosis. We suggest that the combination of 5-FU and CP suppresses the growth of cervical carcinoma cells by synergistic effect with the induction of apoptosis. In vitro synergistic effect of 5-FU and CP supports the basis of the clinical application of the combination chemotherapy to the patients with cervical cancer.

Effects of cisplatin and gamma-irradiation on cell survival, the induction of chromosomal aberrations and apoptosis in SW-1573 cells

PURPOSE

Cisplatin was found to radiosensitize SW-1573 cells by inhibition of PLDR. Therefore, it was investigated whether cisplatin combined with gamma-radiation leads to an increase in the number of chromosomal aberrations or apoptotic cells compared with radiation alone.

METHODS

Confluent cultures of the human lung carcinoma cell line SW-1573 were treated with 1 microM cisplatin for 1 h, 4 Gy gamma-radiation, or a combination of both. Cell survival was studied by the clonogenic assay. Aberrations were analysed by FISH in prematurely condensed chromosomes (PCC) and the induction of apoptosis by counting fragmented nuclei.

RESULTS

A radiosensitizing effect of cisplatin on cell survival was observed if time for PLDR was allowed. An increased number of chromosomal fragments were observed immediately after irradiation compared with 24 h after irradiation whereas color junctions are only formed 24 h after irradiation. No increase in chromosomal aberrations was found after combined treatment, but a significantly enhanced number of fragmented nuclei were observed when confluent cultures were replated after allowing PLDR.

CONCLUSION

The inhibition of PLDR by cisplatin in delayed plated SW-1573 cells did not increase chromosomal aberrations, but increased the induction of apoptosis.

Chemotherapy in the primary treatment of cervical carcinoma

Two major treatment modalities in cervical cancer include radiotherapy and surgery. In an attempt to improve the outcome, these modalities have been increasingly supplemented by chemotherapy. Chemotherapy can be combined with local therapies in various sequences. Of the two possible strategies using chemotherapy and radiotherapy (sequential or concomitant), the latter seems to be more effective. Platinum-based regimens applied concurrently with both definitive and post-operative radiation therapy were demonstrated to provide survival benefit in five of the six recently published randomised trials. The positive impact of chemotherapy added to radiotherapy has also been shown in a meta-analysis including 1894 patients in 19 randomised studies. This strategy, however, is accompanied by increased early toxicity. The benefit of chemotherapy applied prior to surgery remains debatable. The role of new cytotoxic and biological substances, as well as agents combating tumour hypoxia, warrants further clinical investigation.

Enhanced sensitivity to the HER1/epidermal growth factor receptor tyrosine kinase inhibitor erlotinib hydrochloride in chemotherapy-resistant tumor cell lines

PURPOSE

Erlotinib (Tarceva, OSI-774) is a potent and specific inhibitor of the HER1/epidermal growth factor receptor (EGFR) tyrosine kinase. In phase II clinical studies, oral erlotinib monotherapy has shown antitumor activity in patients with advanced non-small cell lung cancer, head and neck cancer, and ovarian cancer after the failure of standard chemotherapy. We hypothesized that some tumors treated with multiple cytotoxic therapies may become more dependent on the HER1/EGFR signaling pathways for survival.

EXPERIMENTAL DESIGN

The growth-inhibitory effect of erlotinib was tested on 10 pairs of chemosensitive, parental, and chemoresistant tumor cell lines.

RESULTS

Enhanced sensitivity to erlotinib was observed in the doxorubicin-resistant human breast cancer cell line MCF-7, paclitaxel-resistant human ovarian carcinoma cell line A2780, and cisplatin-resistant human cervical carcinoma cell line ME180. The IC(50) values of erlotinib in the resistant cell lines were 2- to 20-fold lower than those in the corresponding parental cell lines. This enhanced sensitivity to erlotinib correlated with higher HER1/EGFR and phospho-HER1/EGFR expression when compared with the corresponding parental cell lines. Acquired resistance to cytotoxic agents was not associated with cross-resistance to erlotinib. AE-ME180/CDDP-resistant xenografts showed greater sensitivity to erlotinib than parental ME180 xenografts did.

CONCLUSIONS

Our findings suggest that acquired resistance to cytotoxic therapy in some tumors is associated with enhanced sensitivity to HER1/EGFR inhibitors, which correlates with increased HER1/EGFR expression. These data may explain some of the observed clinical activity of HER1/EGFR inhibitors in patients previously treated with multiple therapies. HER1/EGFR tyrosine kinase inhibitors may be more effective as second- or third-line treatment for certain patients with tumors that were previously treated with multiple chemotherapy regimens.

Concurrent weekly cisplatin and radiotherapy in routine management of cervical cancer: a report on patient compliance and acute toxicity

PURPOSE

To evaluate patient compliance and acute toxicity accompanying concurrent weekly cisplatin and radiotherapy (RT) in the routine management of cervical cancer.

METHODS AND MATERIALS

Locally advanced or high-risk early-stage cervical cancer patients treated with RT and concurrent weekly cisplatin at a dose of 40 mg/m(2) i.v. (maximum dose, 70 mg) for five cycles. Definitive RT included whole pelvis external beam RT to the International Commission on Radiation Units and Measurements reference dose of 40 Gy plus a 10-Gy boost to the parametrium and two brachytherapy applications of 20 Gy to point A each. Postoperative RT consisted of pelvic external beam RT to the International Commission on Radiation Units and Measurements reference dose of 50 Gy and one brachytherapy application of 30 Gy at a depth of 0.5 cm from the applicator surface.

RESULTS

Included in this analysis were 112 consecutive cervical cancer patients treated at one institution with concurrent cisplatin and RT between May 1999 and September 2002. The median age was 48 years (range, 28-79 years). Definitive RT was administered to 57 International Federation of Gynecology and Obstetrics "bulky" Stage IB or IIB-IVA patients, and 53 patients underwent postoperative RT; 2 patients underwent RT for stump carcinoma. All but 2 patients (both administered definitive RT) completed RT. A total of 454 cisplatin cycles were administered (median 4 cycles/patient, range 1-6). Overall, 74% of patients received at least four cycles of cisplatin. The planned five cisplatin cycles were administered to 50 patients (45%); 42% were irradiated definitively and 47% postoperatively. The full and timely planned cisplatin dose was administered to 29 patients (26%). For 29% of patients, the interval between cycles was prolonged because of toxicity (n = 11; 10%) or for reasons not related to toxicity (n = 10; 9%). Of the 112 patients, 62 (55%) did not undergo the planned five cycles of cisplatin because of treatment toxicity (n = 35; 31%) or noncompliance with the treatment schedule because of delayed administration of the first cycle or omission of a cycle for reasons other than toxicity (n = 23; 21%). The most common side effects resulting in chemotherapy discontinuation included GI complications (n = 7) and impaired renal function (n = 5). Of the 112 patients, 49 (44%) experienced Grade 1 or 2 leukopenia and 6 (5%) Grade 3 or 4 leukopenia.

CONCLUSION

Our results show that pelvic RT combined with weekly cisplatin in cervical cancer patients is accompanied by considerable acute toxicity. Furthermore, a number of patients were unable to comply with the treatment schedule owing to reasons unrelated to treatment toxicity. Thus, administration of the full chemotherapy dose may be difficult, although the delivery of planned RT was generally not compromised. Additional follow-up is needed to assess the late toxicity of combined modality treatment.

Evaluation of concurrent and adjuvant carboplatin with radiation therapy for locally advanced cervical cancer

OBJECTIVE

To analyze the toxicity profile and long-term outcomes of patients receiving carboplatin with concurrent radiation for locally advanced cervical cancer.

METHODS

A retrospective study was performed to identify patients treated with carboplatin and concurrent radiation therapy for locally advanced cervical cancer with a minimum follow-up period of 24 months. Records were reviewed for demographic data, chemotherapy doses, toxicities, and survival outcomes. Specifically reviewed were hematologic, gastrointestinal, and renal toxicities and the need for dose modification and treatment delays.

RESULTS

Twenty-one patients with cervical carcinoma Stage IIB (7), III (13), or IVA (1) treated with carboplatin chemotherapy from 1993 to 2001 were identified. Carboplatin at a dose of 300 mg/m(2) administered every 3 weeks for an intended six courses was initiated at the start of radiation therapy. No grade 3 or 4 thrombocytopenia or renal toxicity was observed. Nine patients had delays in chemotherapy administration and/or received a 25% reduction in the dose of chemotherapy based on one or more of the following: thrombocytopenia (platelet count <100000 cells/mcl) (n = 3), granulocytopenia (ANC <1.0) (n = 4), or anemia (hemoglobin <10.0 g/dl) (n = 5). The median carboplatin AUC was 3.9 (range 3.0-5.0). Six patients developed recurrent disease (five local and one distant) with a pelvic control rate of 76% and an overall survival of 71%.

CONCLUSION

Carboplatin at a dose of 300 mg/m(2) (equivalent to an AUC of 3.9) on an every 3-week schedule is tolerable with concurrent pelvic radiation therapy for locally advanced cervical cancer. The efficacy of carboplatin, compared to cisplatin, as a radiation sensitizer can only be determined in a randomized clinical trial.

Treatment with Alstonia scholaris Enhances Radiosensitivity In vitro and In vivo

The radiosensitizing effect of 5 micrograms/mL of alkaloid fraction of Alstonia scholaris (ASERS) was evaluated in various neoplastic cell lines, namely: HeLa, HePG2, HL60, MCF-7, and KB exposed to 0, 0.5, 1, 2, 3, and 4 Gy of gamma-radiation. The irradiation of various cells caused a dose-dependent elevation in the cytotoxicity, and a maximum cytotoxic effect was observed at 4 Gy (the highest dose) in all the cell lines studied. The ASERS pretreatment increased the effect of radiation as evidenced by enhanced cell killing when compared with the concurrent phosphate-buffered saline (PBS) treated irradiation group. The greatest elevation in cell killing was observed for HeLa and KB cells, followed by HL60, MCF7, and HePG2 cells. The in vitro observations were confirmed by in vivo studies, where the Ehrlich ascites carcinoma (EAC) bearing mice were treated with 120 mg/kg body weight of ASERS before exposure to 0, 1, 2, 4, 6, and 8 Gy of hemibody (below the rib cage) gamma-radiation. Irradiation of EAC mice caused a dose-dependent tumor regression, as evidenced by increased life span of the animals. The pretreatment of tumor-bearing animals with 120 mg/kg ASERS resulted in a further remission in the tumor when compared with the concurrent nondrug-treated irradiated controls; as a result there was a radiation dose-dependent increase in the life span of tumor-bearing animals receiving 120 mg/kg ASERS, except for 8 Gy, where it was less than the concurrent control. The above findings corroborate with a time-dependent decrease in the glutathione (GSH) contents, accompanied by an increase in lipid peroxidation. Our study demonstrates that ASERS treatment enhances the effect of radiation and results in disease-free survival of the mice.

Patterns of disease recurrence influenced by hematogenous tumor cell dissemination in patients with cervical carcinoma of the uterus

BACKGROUND

The presence of isolated tumor cells (ITC) in the bone marrow at the time of primary diagnosis indicates an increased risk for subsequent development of distant metastases in various solid tumors. This study evaluates the prevalence and prognostic significance of ITC in patients with primary carcinoma of the cervix uteri.

METHOD

We immunocytochemically analyzed bone marrow aspirates of 130 patients with newly diagnosed carcinoma of the cervix uteri for the presence of cytokeratin(CK)-positive cells from May 1994 to January 2001. We used a quantitative immunoassay with the monoclonal anti-CK antibody A45-B/B3 and evaluated 2 x 10(6) bone marrow cells per patient. Patients were followed prospectively for a median of 43 (range, 1-85) months.

RESULTS

Isolated tumor cells were found in the bone marrow of 38 patients (29%). The presence of ITC did not correlate with the International Federation of Gynecology and Obstetrics (FIGO) tumor stage (P = 0.61), pelvic and paraaortal lymph node involvement (P = 0.41), histopathologic grading (P = 0.67), the histologic type of the carcinoma (P = 0.93), invasion of lymph nodes (P = 0.93) and blood vessels (P = 0.92), or with menopausal status (P = 0.17). The bone marrow status at the time of primary diagnosis did not correlate with the overall survival as estimated by Kaplan-Meier analysis (P = 0.30). However, distant metastases occurred in 5% of the patients (n = 5) with negative bone marrow status and in 15% of the patients (n = 6) with positive bone marrow status (P = 0.054). The median distant disease-free survival period was 78 months (95% confidence interval 73-82) in patients with negative bone marrow status and 72 months (95% CI 61-82) in patients with positive bone marrow status (P = 0.051). Multivariate analysis revealed the presence of ITC as a significant, independent risk factor for the subsequent development of distant metastases (relative risk 3.6, P = 0.046).

CONCLUSION

Despite the locoregional predominance of cervical carcinoma at the time of primary diagnosis, the presence of ITC in the bone marrow indicates an increased risk for the development of distant metastases. This information may prove useful to stratify patients for systemic treatment.

The action of ionizing irradiation alone or in combination with cisplatin on malignant cells: Investigations in vitro

The paper gives a brief review of the literature data based on in vitro investigations of cytotoxic action of cisplatin and irradiation, applied alone or in combination, to carcinoma cell lines and fresh tumor explants. Presented data, observed in the light of data obtained in clinics, indicate that in vivo some additional tumor destructive activity might be induced by applied therapy. Therefore examinations of the antitumor effect of some treatment need to be more complex and must include determination of the effects of applied therapy on set of parameters, which control tumor growth in vivo.

Hypersensitivity reaction to cisplatin during chemoradiation therapy for gynecologic malignancy

Hypersensitivity reactions to intravenous cisplatin are rare. The appearance of hypersensitivity reactions in 4 of 25 consecutive patients treated with concomitant pelvic radiation and weekly intravenous cisplatin for gynecologic malignancies is reported. The reactions appeared within hours of cisplatin delivery and included primarily fever, rash, and pruritus. Infection was ruled out by blood cultures and other laboratory studies. Affected patients were treated prophylactically with an antihistamine before subsequent courses of cisplatin, with excellent results. The high rate of hypersensitivity reactions in our series may be attributable to tumor necrosis and cytokine release caused by the pelvic irradiation. Clinicians should be aware of this potential side effect so that early premedication regimens can be instituted to prevent unnecessary toxicity.

[Chemoradiotherapy in locally advanced cancers of the uterine neck. Retrospective study of 92 patients treated at the Institute Curie between 1986 and 1998]]

PURPOSE

The prognosis of locally advanced cervix cancers is poor with metastatic and local recurrence risks. Recent publications reported that concurrent chemotherapy and pelvic radiation increased local control compared to radiotherapy alone. Chemotherapy could also decrease metastatic recurrences. We report 92 cases of patients with locally advanced cervix cancer treated between 1986 and 1998 at the Institut Curie.

PATIENTS AND METHODS

Concurrent chemoradiation was exclusive in 51 cases and added to surgery in 41 cases. Chemotherapy with 5FU-Cisplatin-Mitomycin C-Vindesin (protocol A) was performed for 43% of patients and 57% of them received 5FU-Cisplatin alone (protocol B).

RESULTS

Median follow-up was 64 months (6-149 months). Five-year disease-free survival rate was 47% and local control rate was 70%. Disease-free survival was correlated with therapeutic response. After exclusive chemoradiation, the good responsive patients had a better DFS (54% vs 26%, p = 0.018). In the surgery group, those patients with sterilized lymph nodes and tumours had also a higher DFS (76% vs 47%, p = 0.036). Toxicity was higher with protocol A.

CONCLUSION

From our study, it appears that local control of advanced cervix cancers is better with combined chemoradiotherapy but disease-free survival stays low according to the metastatic evolution. Metastasis without local recurrence remained frequent in our study. 5FU-CDDP chemotherapy has a lower toxicity and is as effective as 5FU-CDDP-Mitomycin C-Vindesin protocol, in association with radiotherapy.

Concurrent chemoradiotherapy with gemcitabine and cisplatin for pancreatic cancer: from the laboratory to the clinic

PURPOSE

We have reported that gemcitabine and concurrent radiation is a promising therapy for patients with pancreatic cancer. We investigated whether the addition of cisplatin, which may increase the systemic efficacy of gemcitabine, would be synergistic with gemcitabine and/or radiation in human pancreatic cancer cell lines.

METHODS AND MATERIALS

BxPc3 and Panc-1 human pancreatic cancer cells were treated with three different schedules before radiation: (A) a sequential incubation of gemcitabine for 2 h followed by cisplatin for 2 h, (B) gemcitabine for 2 h, followed by washout of drug, replenishment of media for a 24-h incubation, followed by cisplatin for 2 h, and (C) gemcitabine for 24 h with a concurrent incubation of cisplatin for the last 2 h. Cells were assessed for clonogenic survival using a standard assay. Synergism was evaluated by the median effect analysis.

RESULTS

The schedule shown to be maximally synergistic for both cell lines was the consecutive 2-h gemcitabine, 2-h cisplatin exposure, particularly at surviving fractions of <0.5. Cisplatin did not produce radiosensitization nor did it affect gemcitabine-mediated radiosensitization.

CONCLUSION

Cisplatin produces synergistic cytotoxicity with gemcitabine without compromising gemcitabine-mediated radiosensitization. On the basis of these laboratory and previous clinical observations, we have initiated a Phase I trial of cisplatin plus gemcitabine and radiotherapy in patients with unresectable pancreatic cancer.

Chemoradiotherapy for cervical cancer

Cervical cancer remains a major health problem worldwide, despite advances in screening. For patients with locally advanced stage disease, failure to obtain local-regional control usually results in death. In an effort to improve local-regional tumour control, neoadjuvant and concurrent chemoradiation has been tested. Recently, five randomised trials performed by the Gynecologic Oncology Group (GOG), Radiation Therapy Oncology Group (RTOG) and the SouthWest Oncology Group (SWOG) studying cisplatin-based chemoradiation have demonstrated a significant survival advantage. Three of the trials compared cisplatin-based concurrent chemotherapy and radiation to radiation alone and two trials compared cisplatin-based concurrent chemotherapy and radiation to radiation with hydroxyurea. In all of the trials, cisplatin-based chemotherapy administered concurrently with radiation therapy was more effective at reducing the risk of death by 30-50%. Acute toxicities, principally neutropenia and gastrointestinal, were more common with chemoradiation, but were transient and the rates of late complications (complications that persisted or occurred for more than 60 days after the treatment) were similar. Based on the results of these five randomised trials, the National Cancer Institute (NCI) released a Clinical Announcement stating that cisplatin-based chemotherapy, as used in these trials (i.e. concurrently with radiation therapy), as the new standard of therapy for cervical cancer.

Targeting DNA mismatch repair for radiosensitization

Postreplicational mismatch repair (MMR) proteins are capable of recognizing and processing not only single base-pair mismatches and insertion-deletion loops (IDLs) that occur during DNA replication, but also adducts in DNA resulting from treatment with cancer chemotherapy agents. These include widely varying types of DNA adducts resulting from methylating agents such as MNNG, MNU, temozolomide, and procarbazine; CpG crosslinks resulting from cisplatin and carboplatin; and S(6)-thioguanine and S(6)-methylthioguanine residues in DNA. Although MMR proteins can recognize both replicational errors and chemotherapy-induced adducts in DNA, the end results of this recognition are very different. Base-base mismatches and IDLs can be repaired by MMR, restoring genomic integrity, whereas MMR-mediated recognition and processing of chemotherapy-induced adducts in DNA results in apoptosis. After the loss of MMR, the inability of cells to recognize and correct single base-pair mismatches and insertion-deletion loops can lead to secondary mutations in proto-oncogenes and tumor-suppressor genes, thereby contributing to the development of cancer. In addition, the inability of MMR-deficient cells to recognize chemotherapy-induced adducts in DNA can result in a damage-tolerant phenotype that translates to clinically significant resistance by allowing for selection of MMR-deficient cancer cells. We have shown recently that these MMR-deficient, drug-resistant cells can be targeted for radiosensitization by the halogenated thymidine analogs iododeoxyuridine (IdUrd) and bromodeoxyuridine (BrdUrd). These thymidine (dThd) analogs become incorporated into DNA and form reactive uracil radicals after ionizing radiation (IR), increasing strand breaks. IdUrd and BrdUrd appear to be removed from DNA in MMR-proficient cells with limited toxicity or disruption of the cell cycle, while accumulating at much higher levels in MMR-deficient cells. As a result, it is possible to effectively increase the radiosensitization of MMR-deficient cells at levels of halogenated dThd analog that demonstrate limited toxicity to MMR-proficient cells. This indicates that a combined approach of IdUrd or BrdUrd with IR may be effective in killing MMR-deficient tumors in patients, which are resistant to many cancer chemotherapy agents commonly used in the clinic.

Chemoradiotherapy: the new standard care for invasive cervical cancer

Cervical cancer remains a major health problem worldwide, despite advances in screening. For patients with locally advanced stage disease, failure to obtain local-regional control usually results in death. In an effort to improve local-regional tumour control, neoadjuvant and concurrent chemoradiation have been tested. Recently, 5 randomised trials performed by the Gynecologic Oncology Group, Radiation Therapy Oncology Group and the Southwest Oncology Group studying cisplatin-based chemoradiation have demonstrated a significant survival advantage. Three of the trials compared cisplatin-based concurrent chemotherapy and radiation to radiation alone and 2 trials compared cisplatin-based concurrent chemotherapy and radiation to radiation with hydroxyurea. In all trials, cisplatin-based chemotherapy administered concurrently with radiation therapy was the more effective therapy, reducing the risk of death by 30 to 50%. Acute toxicities, principally neutropenia and gastrointestinal, were more common with chemoradiation but were transient and rates of late complications were similar between treatment groups. Based on the results of these 5 randomised trials, the National Cancer Institute released a Clinical Announcement stating that cisplatin-based chemotherapy as used in these trials concurrently with radiation therapy should be the new standard of therapy for high risk early stage and locally advanced stage cervical cancer.

Biodistribution and pharmacokinetics of 111In-DTPA-labelled pegylated liposomes in a human tumour xenograft model: implications for novel targeting strategies

The biodistribution and pharmacokinetics of 111In-DTPA-labelled pegylated liposomes in tumour-bearing nude mice was studied to examine possible applications of pegylated liposome-targeted anti-cancer therapies. Nude mice received an intravenous injection of 100 microl of 111In-DTPA-labelled pegylated liposomes, containing 0.37-0.74 MBq of activity. The t1/2alpha and t1/2beta of 111In-DTPA-labelled pegylated liposomes were 1.1 and 10.3 h, respectively. Tumour uptake was maximal at 24 h at 5.5 +/- 3.0% ID g(-1). Significant reticuloendothelial system uptake was demonstrated with 19.3 +/- 2.8 and 18.8 +/- 4.2% ID g(-1) at 24 h in the liver and spleen, respectively. Other sites of appreciable deposition were the kidney, skin, female reproductive tract and to a lesser extent the gastrointestinal tract. There was no indication of cumulative deposition of pegylated liposomes in the lung, central nervous system, musculoskeletal system, heart or adrenal glands. In contrast, the t1/2alpha and t1/2beta of unencapsulated 111In-DTPA were 5 min and 1.1 h, respectively, with no evidence of accumulation in tumour or normal tissues. Incubation of 111In-DTPA-labelled pegylated liposomes in human serum for up to 10 days confirmed that they are very stable, with only minor leakage of their contents. The potential applications of pegylated liposomes in the arena of targeted therapy of solid cancers are discussed.

A survey on staging and treatment in uterine cervical carcinoma in the Radiotherapy Cooperative Group of the European Organization for Research and Treatment of Cancer

BACKGROUND

The treatment outcome of advanced stage uterine cervical carcinoma remains unsatisfactory. In order to elaborate a novel trial within The Radiotherapy Cooperative Group (RCG) of the European Organization for Research and Treatment of Cancer (EORTC), we conducted a survey in 1997-1998 to determine the variability of pre-treatment assessment and treatment options. The variability of choosing surgery, defined radiation therapy techniques and chemotherapy are investigated, as well as the center's choices of future treatment strategies.

METHODS

Fifty two of 81 RCG centers from the RCG have participated in the survey. As one would expect, there is a large variation in the techniques used for pretreatment evaluation and treatment options. There is no 'standard' for reporting acute and late side effects. Chemotherapy is used neither systematically nor uniformly, and some centers continue to use neadjuvant chemotherapy modalities.

RESULTS

Furthermore, the survey reveals that there is a strong demand for the reduction of overall treatment-time, for clinical investigation of novel combined modality treatment strategies, especially chemo-radiation therapy, and also for the use of new radiation sensitizers.

CONCLUSION

We conclude that a more homogeneous approach to the pretreatment evaluation as well as treatment techniques is required in order to allow adequate quality control in any future trial of the RCG in the EORTC.

Concurrent cisplatin-based radiotherapy and chemotherapy for locally advanced cervical cancer

BACKGROUND AND METHODS

On behalf of the Gynecologic Oncology Group, we performed a randomized trial of radiotherapy in combination with three concurrent chemotherapy regimens -- cisplatin alone; cisplatin, fluorouracil, and hydroxyurea; and hydroxyurea alone -- in patients with locally advanced cervical cancer. Women with primary untreated invasive squamous-cell carcinoma, adenosquamous carcinoma, or adenocarcinoma of the cervix of stage IIB, III, or IVA, without involvement of the para-aortic lymph nodes, were enrolled. The patients had to have a leukocyte count of at least 3000 per cubic millimeter, a platelet count of at least 100,000 per cubic millimeter, a serum creatinine level no higher than 2 mg per deciliter (177 micromol per liter), and adequate hepatic function. All patients received external-beam radiotherapy according to a strict protocol. Patients were randomly assigned to receive one of three chemotherapy regimens: 40 mg of cisplatin per square meter of body-surface area per week for six weeks (group 1); 50 mg of cisplatin per square meter on days 1 and 29, followed by 4 g of fluorouracil per square meter given as a 96-hour infusion on days 1 and 29, and 2 g of oral hydroxyurea per square meter twice weekly for six weeks (group 2); or 3 g of oral hydroxyurea per square meter twice weekly for six weeks (group 3).

RESULTS

The analysis included 526 women. The median duration of follow-up was 35 months. Both groups that received cisplatin had a higher rate of progression-free survival than the group that received hydroxyurea alone (P<0.001 for both comparisons). The relative risks of progression of disease or death were 0.57 (95 percent confidence interval, 0.42 to 0.78) in group 1 and 0.55 (95 percent confidence interval, 0.40 to 0.75) in group 2, as compared with group 3. The overall survival rate was significantly higher in groups 1 and 2 than in group 3, with relative risks of death of 0.61 (95 percent confidence interval, 0.44 to 0.85) and 0.58 (95 percent confidence interval, 0.41 to 0.81), respectively.

CONCLUSIONS

Regimens of radiotherapy and chemotherapy that contain cisplatin improve the rates of survival and progression-free survival among women with locally advanced cervical cancer.

Paclitaxel is preferentially cytotoxic to human cervical tumor cells with low Raf-1 kinase activity: implications for paclitaxel-based chemoradiation regimens

BACKGROUND AND PURPOSE

Low Raf- kinase activity has been reported to be associated with radioresistance in epithelial tumor cell lines and with paclitaxel sensitivity in cervical tumor cells. Paclitaxel might thus be effective in eliminating radioresistant clones from cervical tumors, even in the absence of synergistic interaction between these therapeutic modalities. We thus established the relationship between Raf-1 kinase activity and radiosensitivity in human cervical tumor cells and determined if paclitaxel is preferentially cytotoxic to radio-resistant tumor clones.

MATERIALS AND METHODS

We established and contrasted the radiation and paclitaxel sensitivity of 12 human cervical tumor clones that exhibited a wide range of Raf-1 kinase activity.

RESULTS

Raf-1 kinase activity was inversely correlated (P = 0.001) with SF2 values in the 12 cervical tumor clones studied. Paclitaxel was preferentially cytotoxic to radioresistant tumor clones, with the level of paclitaxel-induced cytotoxicity being significantly (P = 0.0016) influenced by Raf-1 kinase activity levels.

CONCLUSIONS

Our in vitro data indicate that there are marked, but completely opposite, Raf-1 kinase dependencies of radiation and paclitaxel cytotoxicity in cervical tumor cells. The use of combined paclitaxel and radiotherapy treatment may thus lead to higher local control rates for squamous cell carcinoma of the cervix. Circumstantially, our data suggest that the greatest therapeutic gains might accrue if paclitaxel was administered when there is the greatest proportion of tumor clones with low Raf-1 kinase activity. It may thus be desirable to use paclitaxel towards the end of radiotherapy treatment or post-radiotherapy as consolidation therapy.

Hydroxyurea, 5-fluorouracil infusion, and cisplatin adjunct to radiation therapy in cervical carcinoma: a phase I-II trial of the Gynecologic Oncology Group

BACKGROUND

In a previous study, the Gynecologic Oncology Group (GOG) compared hydroxyurea (HDXR) and the combination of cisplatin (C) and 5-fluorouracil (5-FU) infusion as potentiators of radiation therapy. This study was undertaken to determine whether these two regimens could be combined, concurrent with pelvic radiation therapy in patients with locally advanced cervical cancer.

METHODS

The GOG entered 75 eligible and evaluable patients on a Phase I-II evaluation of HDXR, C, and 5-FU as adjuncts to radiation therapy for locally advanced carcinoma of the cervix. All patients had histologically verified primary disease and confirmed negative para-aortic lymph nodes. Eligibility was limited to clinical stage IIB through IVA. HDXR was given orally, twice weekly at a dose of 2.5 g/m2; C on Days 1 and 29 at 50 mg/m2; and 5-FU by 96-hr infusion on Days 2-5 and 30-33 at a starting dose of 800 mg/m2.

RESULTS

Forty-eight (64%) patients had stage IIB disease, 25 (33%) had stage IIIB, and 2 had stage IVA tumors. Primary tumors 4 cm or less in size were present in 15 patients, between 4 and 6 cm were in 27 patients, and larger than 6-cm were observed in 33 patients. Grade 3/4 acute toxicity was experienced by 41 (54.7%) patients. These acute toxicities caused delays in prescribed radiation therapy of more than 1 week in 14 (18.9%) and low doses of drug in 16 (21.3%), and only 26 (34.7%) patients had the scheduled dose escalation of 5-FU on their second course. Clinical response was excellent with complete and partial response rate of 93.3%. Median time to progression has not been reached.

CONCLUSION

Although this dose and schedule could be successfully administered, the delays in therapy should be avoided by a lower starting dose of hydroxyurea. Stomatitis was not a dose-limiting toxicity. These results have formed the basis of a phase III trial comparing this regimen to two other chemoradiation regimens.

Differential level of DSB repair fidelity effected by nuclear protein extracts derived from radiosensitive and radioresistant human tumour cells

A cell-free plasmid reactivation assay was used to determine the fidelity of DNA double-strand break (DSB) repair in a panel of eight DSB repair-proficient human tumour cell lines. Nuclear protein extracts derived from radiosensitive tumour cells were less capable of correctly rejoining EcoRI-induced DSBs than were similar extracts from radioresistant tumour cells. Linear regression analysis suggests that there was a significant (r2 = 0.84, P = 0.001, d.f. = 6) correlation between the fidelity of DSB rejoining and the SF2 values of the cell lines studied. This cell-free assay is clearly sensitive to differences in the nuclear protein composition that reflect the clinically relevant radiosensitivity of these cell lines. The fact that our cell-free assay yielded similar results to previous studies that used intracellular plasmid reactivation assays suggests that those differences in DSB mis-rejoining frequencies in radiosensitive and radioresistant cell lines may be due to inherent differences in nuclear protein composition and are not directly attributable to differences in proliferation rates between cell lines. The underlying cause for this association between DSB mis-rejoining frequencies and radiosensitivity is presently unknown, however restriction endonuclease mapping and polymerase chain reaction (PCR) amplification analysis revealed that approximately 40% of the mis-rejoined DSBs arose as a result of the deletion of between 40 and 440 base pairs. These data raise the possibility that the radiosensitivity of DSB repair-proficient human tumour cell lines may be partly determined by the predisposition of these cell lines to activate non-conservative DSB rejoining pathways.

Intratumoral heterogeneity as a confounding factor in clonogenic assays for tumour radioresponsiveness

The level of intra-tumoral heterogeneity of cellular radiosensitivity within primary cultures of three carcinomas of the cervix has been established. All three cultures contained clones that varied by as much as 3-fold in their clinically relevant radiosensitivity (SF2). The level of intra-tumoral heterogeneity observed in these cervical tumour cultures was sufficient to be a major confounding factor to the use of pre-treatment assessments of radiosensitivity to predict for clinical radioresponsiveness. Mathematical modeling of the relative elimination of the tumour clones during fractionated radiotherapy indicates that, in two of the three biopsy samples, the use of pre-treatment derived SF2 values from the heterogeneous tumour sample would significantly overestimate radioresponsiveness. We conclude that assays of cellular radiosensitivity that identify the radiosensitivity of the most radioresistant clones and measure their relative abundance could potentially increase the effectiveness of SF2 values as a predictive marker of radioresponsiveness.