Elisabeth Åvall Lundqvist

Pharmacogenetic Studies of Paclitaxel in the Treatment of Ovarian Cancer

The purpose of this study was to evaluate the role of sequence variants in the CYP2C8, ABCB1 and CYP3A4 genes and the CYP3A4 phenotype for the pharmacokinetics and toxicity of paclitaxel in ovarian cancer patients. Thirty-eight patients were treated with paclitaxel and carboplatin. The genotypes of CYP2C8*1B, *1C, *2, *3, *4, *5, *6, *7, *8 and P404A, ABCB1 G2677T/A and C3435T, as well as CYP3A4*1B, were determined by pyrosequencing. Phenotyping of CYP3A4 was performed in vivo with quinine as a probe. The patients were monitored for toxicity and 23 patients underwent a more extensive neurotoxicity evaluation. Patients heterozygous for G/A in position 2677 in ABCB1 had a significantly higher clearance of paclitaxel than most other ABCB1 variants. A lower clearance of paclitaxel was found for patients heterozygous for CYP2C8*3 when stratified according to the ABCB1 G2677T/A genotype. In addition, the CYP3A4 enzyme activity in vivo affected which metabolic pathway was dominant in each patient, but not the total clearance of paclitaxel. The exposure to paclitaxel correlated to the degree of neurotoxicity. Our findings suggest that interindividual variability in paclitaxel pharmacokinetics might be predicted by ABCB1 and CYP2C8 genotypes and provide useful information for individualized chemotherapy.

EGFR protein overexpression and gene copy number increases in oral tongue squamous cell carcinoma

New promising therapeutic agents targeting epidermal growth factor receptor (EGFR) have been developed although clinical information concerning EGFR status in oral tongue squamous cell carcinoma (OTSCC) is limited. We investigated EGFR protein expression and gene copy numbers in 78 pretreatment OTSCC paraffin samples. EGFR protein expression was found in all 78 tumours, of which 72% showed an intense staining. Fifty-four percent of the tumours had high (> or =four gene copies) EGFR gene copy numbers. EGFR gene copy number was significantly associated with EGFR protein expression (P=0.002). Pretreatment EGFR staining intensity tended to be associated with non-pathological complete remission after preoperative radiotherapy for Stage II OTSCC. No correlation was found between EGFR status and survival. EGFR FISH results were significantly (P=0.003) higher in more advanced tumours (Stages II, III and IV) than in the tumours in Stage I. Non-smokers exhibited a significantly higher EGFR gene copy number and protein overexpression in Stages I and II OTSCC than smokers (P=0.001, P=0.009). In conclusion, EGFR was found to be overexpressed in all OTSCCs making this cancer type interesting for exploring new therapeutic agents targeting the EGFR receptor.

Protein markers of cancer-associated fibroblasts and tumor-initiating cells reveal subpopulations in freshly isolated ovarian cancer ascites.

BackgroundIn ovarian cancer, massive intraperitoneal dissemination is due to exfoliated tumor cells in ascites. Tumor-initiating cells (TICs or cancer stem cells) and cells showing epithelial-mesenchymal-transition (EMT) are particularly implicated. Spontaneous spherical cell aggregates are sometimes observed, but although similar to those formed by TICs in vitro, their significance is unclear.MethodsCells freshly isolated from malignant ascites were separated into sphere samples (S-type samples, n=9) and monolayer-forming single-cell suspensions (M-type, n=18). Using western blot, these were then compared for expression of protein markers of EMT, TIC, and of cancer-associated fibroblasts (CAFs).ResultsS-type cells differed significantly from M-type by expressing high levels of E-cadherin and no or little vimentin, integrin-β3 or stem cell transcription factor Oct-4A. By contrast, M-type samples were enriched for CD44, Oct-4A and for CAF markers. Independently of M- and S-type, there was a strong correlation between TIC markers Nanog and EpCAM. The CAF marker α-SMA correlated with clinical stage IV. This is the first report on CAF markers in malignant ascites and on SUMOylation of Oct-4A in ovarian cancer.ConclusionsIn addition to demonstrating potentially high levels of TICs in ascites, the results suggest that the S-type population is the less tumorigenic one. Nanoghigh/EpCAMhigh samples represent a TIC subset which may be either M- or S-type, and which is separate from the CD44high/Oct-4Ahigh subset observed only in M-type samples. This demonstrates a heterogeneity in TIC populations in vivo which has practical implications for TIC isolation based on cell sorting. The biological heterogeneity will need to be addressed in future therapeutical strategies.

Fluorescence in situ hybridization markers for prediction of cervical lymph node metastases.

The presence of lymph node metastases is associated with poor prognosis in early stage cervical cancer. As of yet, no molecular markers predicting lymph node metastases have been identified. We examined single genetic markers and a composite marker, comprised of three fluorescence in situ hybridization (FISH) probes targeting the genes LAMP3, PROX1, and PRKAA1, in pretreatment cervical biopsies from 16 lymph node positive cases and 15 lymph node negative controls from women with stage IB and IIA cervical cancer. In addition, we determined clonal patterns by including CCND1 to compare the clonal constitution of primary tumors and associated lymph node metastases. The composite FISH marker allowed for classification of patients into those with and without lymph node metastases with a sensitivity and specificity of 75% and 87%, respectively (P = 0.001). The positive predictive value and negative predictive value were 86% and 76%, respectively. Clonal patterns varied among the tumors. In many cases, changes between the primary tumor and lymph node metastases in the most common clones may indicate that certain clones have a growth advantage for establishing metastases in lymph nodes. We conclude that the composite FISH marker may be useful for determining risk for subsequent development of lymph node metastases in patients with cervical cancer.

Phylogenetic Analysis of Multiple FISH Markers in Oral Tongue Squamous Cell Carcinoma Suggests that a Diverse Distribution of Copy Number Changes Is Associated with Poor Prognosis

Oral tongue squamous cell carcinoma (OTSCC) is associated with poor prognosis. To improve prognostication, we analyzed four gene probes (TERC, CCND1, EGFR and TP53) and the centromere probe CEP4 as a marker of chromosomal instability, using fluorescence in situ hybridization (FISH) in single cells from the tumors of sixty‐five OTSCC patients (Stage I, nu2009=u200915; Stage II, nu2009=u200930; Stage III, nu2009=u20097; Stage IV, nu2009=u200913). Unsupervised hierarchical clustering of the FISH data distinguished three clusters related to smoking status. Copy number increases of all five markers were found to be correlated to non‐smoking habits, while smokers in this cohort had low‐level copy number gains. Using the phylogenetic modeling software FISHtrees, we constructed models of tumor progression for each patient based on the four gene probes. Then, we derived test statistics on the models that are significant predictors of disease‐free and overall survival, independent of tumor stage and smoking status in multivariate analysis. The patients whose tumors were modeled as progressing by a more diverse distribution of copy number changes across the four genes have poorer prognosis. This is consistent with the view that multiple genetic pathways need to become deregulated in order for cancer to progress.

Principles of chemotherapy.

Chemotherapy plays a major role in the treatment of patients with gynecological malignancies. In general, chemotherapy has a smaller therapeutic window compared with drugs of other types; hence, the potential for severe adverse effects associated with chemotherapy has made appropriate patient and drug selection critical. Before initiating treatment of any patient with a chemotherapeutic agent, the following issues should be considered:

Initial experiences with serum alkaline DNase activity in monitoring the effects of therapy for carcinoma of the uterine cervix

The objective was to evaluate if variations in serum alkaline DNase activity (SADA) can predict the effects of therapy in women with early stages of primary cervical carcinoma. 29 out of 33 patients had no evidence of disease after therapy. Only 5 out of the 29 women showed increased SADA levels after therapy compared with the pretreatment SADA value. Of the 4 women with evidence of disease after therapy, 3 had unchanged or decreased SADA levels. We conclude that serum alkaline DNase activity seems to have little to offer in predicting the effects of treatment in stage I and stage II cervical carcinoma.

Data quality in the Swedish Quality Register of Gynecologic Cancer – a Swedish Gynecologic Cancer Group (SweGCG) study

Abstract Aim: The aim of this study is to evaluate the quality of data on endometrial (EC) and ovarian, fallopian tube, peritoneal, abdominal or pelvic cancers (OC) registered in the Swedish Quality Register of Gynecologic Cancer (SQRGC). Method: A random sample of 500 patients was identified in the SQRGC and their medical charts were reviewed for re-abstraction of 31 selected core variables by an independent validator. The data in the SQRGC and the re-abstracted data were compared. The data were collected from 25 hospitals evenly distributed throughout Sweden. The main outcomes were comparability, timeliness, completeness and validity. Coverage was compared with the National Cancer Register (NCR). Timeliness was defined as the speed of registration i.e. when patients were registered in the SQRGC relative to date of diagnosis. Internationally accepted coding systems for stage, grading and histologic type were used ensuring a high degree of comparability. Correlations were estimated using Pearson’s correlation coefficient and Cohen´s kappa coefficient. Results: The completeness was 95%. The timeliness was 88–91% within 12 months of diagnosis. The median degree of agreement between re-abstracted data and data in the SQRGC was 82.1%, with a median kappa value of 0.73 for ordinate variables and a median Pearson’s correlation coefficient of 0.96. The agreements for the type of surgery were 76% (95% CI 70–81%; kappa 0.49) and type of primary treatment 90% (95% CI 87–94%; kappa 0.85) in OC and in EC 88% (95% CI 84–93%; kappa 0.84). The agreements for the FIGO stage were in OC and EC 74% (95% CI 68–80%; kappa 0.69) and 87% (95% CI 82–91%; kappa 0.79), respectively. Conclusions: The data in the Swedish Quality Register for Gynecologic Cancer are of adequate quality in order to be used as a basis for research and to evaluate possible differences in treatment, lead times and treatment results.

Targeted therapy in gynecologic cancers: Ready for prime time?

Each year, around 225 000 women are diagnosed with ovarian cancer and over 140 000die [1]. Despite the recent advances in understanding the role of proper staging in early cases, maximal debulking efforts, and new modes and route of adjuvant (including intraperitoneal and dose-dense regimen), neoadjuvant, and palliative chemotherapeutic interventions, recurrences are inevitable and survival rates are still dismal in the advanced stages. Similarly, cervical cancer remains a major killer of women in lowresource countries and in women of low socioeconomic status in highresource countries. In 2012, 528 000 women were affected and 226 000 died of their disease [1]. Despite the recent advances in primary prevention (HPV vaccination) and secondary prevention (screening by cytology and/or HPV testing and subtyping), most women in lowresource countries have no access to either vaccination or screening, and still present at a late stage. Although early-stage and locally advanced cancers may be cured with radical surgery, chemoradiotherapy, or both, these modalities are scare in low-resource countries. Moreover, patients with metastatic cancers and those with persistent or recurrent disease after platinumbased chemoradiotherapy have limited options [2,3]. In both of these cancers, new forms of therapy are needed. Increasing knowledge of the genetic basis for various cancers has led to the development of new drugs that are tailored to these specific cancer pathways, while sparing normal cells and reducing the toxic adverse effects of classical chemotherapy.