Basic and Clinical Cancer Research
Volume:3 Issue: 2, Spring 2011

Acute lymphoblastic leukemia (ALL) constitutes a heterogeneous group of diseases characterized by abnormal proliferation and accumulation of immature lymphoblasts arrested at various differentiation stages. Increasing evidence suggests that chromosomal defects are present in these patients. The aim of this study is to investigate the chromosomal radiosensitivity in a group of ALL patients. To analyze chromosomal radiosensitivity of ALL patients, lymphocytes of 20 patients were cultured followed by exposure to γ-ray irradiation to detect the chromosomal aberrations as an indicator of radiosensitivity. Cells were scored for the number of aberrations (chromatid breaks, chromatid gaps, chromosome breaks, chromosome gaps and chromatid exchanges). Results were compared with healthy individuals, and ataxia telangiectasia (AT) patients as positive control. On average number of aberrations in ALL patients was significantly higher than that in healthy controls. We found 65% of ALL patients appeared to be susceptible to in vitro irradiation. Chromosomal radiosensitivity of 35% patients was not different from healthy donors. Ataxia telangiectasia patients showed the highest degree of lymphocyte radiosensitivity. The results also indicate that there is a good correlation between the two assays, G2 and G0, using the same blood sample for both assays. According to the result, we concluded that most of the ALL patients are sensitive to ionizing radiation and therefore should be protected from unnecessary diagnostic and therapeutic procedures using ionizing radiation.

Cancer registries are important infrastructure for cancer control programs. However most developing countries lack population based cancer registry. In Iran there cancer incidence is estimated based on pathology-based cancer registry. In this study we evaluated results of the nationwide pathology-based cancer registry in Iran. We compared age-standardized incidence rate (ASRs) of all cancers combined among male and female from 2004 to 2006 for the entire country and stratified by 30 provinces. In addition, we compared ASRs of all cancer combined and six common cancers from pathology-based cancer registry with the results of population-based cancer registry conducted in five provinces including Tehran, Aradbil, Kerman, Golestan, and Semnan provinces. Ratio of pathology-based to population-based cancer registries in these provinces perceived as the completeness of pathology-based cancer registry. We found that ASRs among men and women increased from 2004 to 2006. However, the increasing trend was not consistent for all 30 provinces; ASRs increased, decreased on remained stable in different provinces. Completeness of pathology-based cancer registry was about 58% and 64% for men and women, respectively. Among the other, the completeness was extremely low for lung (26%) and esophageal (53%), and stomach (54%) cancers among male and for stomach (54%) and ovary (0.68%) among female. Pathology-based cancer registry underestimates the cancer incidence and cannot be a reliable source for policy making and research. Inclusion of other sources such as death registry and establishment of population-based cancer registry is necessary. We suggest promoting regional population-based registries using standard methods in Iran and other developing countries.

Numerous epidemiologic studies have shown that esophagus cancer is more common in areas with grains containing mycotoxin such as fumonisin B1 (FB1). The aim of this research is to study the effect of long- and short-term of esophagus tissue to fB1 orally administered in animal model. Forty-four female mice have been divided in two short- and long-term groups that further subdivided into control and therapeutic subgroups. FB1 (25 mg/50 g birthweight) has been gavaged for 4 weeks in the short-term therapeutic subgroups and FB1 (10 mg/l) has been used in drinking water for 12 months in the long-term group. At the end of study, liver and esophagus tissues have been studied for histo-pathological changes. Also genes expression of c-myc، TGF-α، HGF AFP and P53 were detected by using RT-PCR method. In short- and long-term groups (6 and 9 months) no macroscopic and microscopic sign were observed in the various organs. But in the microscopic examination of the liver (9 and 12 months) mild dysplasia of hepatocytes with aniso nucleus, increased Kupffer cells and nucleolus deposit of hyalonoid amorphous in liver media layer were observed. In immunohistochemical study, nuclear dysplastic of hepatocytes were detected with increased staining and hyalonoid amorphous deposit. Our results indicate that even though no pathologic changes in the esophagus tissue have been found in the short- and long-term exposure to FB1, however, metabolic effects of FB1 in animal's parenchyma organs especially liver, kidney and lung warrants further study.

Idiopathic retroperitoneal fibrosis is a rare disorder of an unknown etiology characterized by an inflammatory proliferative fibrosing process that may involve the ureters in 80-100% of cases. The present study was carried on a 38 years old man who was admitted to Imam Khomeini Hospital with severe abdominal pain and renal failure. Abdominal MRI showed encasement of abdominal aorta and bilateral hydroureteronephrosis. Tissue biopsy established the diagnosis of retroperitoneal fibrosis and ureteral obstruction was managed by insertion of bilateral ureteral stents. Presupposing the un-resectability, medical therapy was started. However he didn’t show objective response to Prednisolone (1mg/kg) and had adverse effects. Subsequently, his disease was controlled by adding mycophenolate mofetil and azathioprine to reduce the steroid dose. After a few months, urinary stents were removed and he had been on complete remission for more than 4 years. Although advanced idiopathic retroperitoneal fibrosis would be effectively treated by a combination of ureteric stents and steroids, in difficult cases, second-line treatment with other immunosuppressive drugs may help to achieve long-term remission of disease.

Delivering the maximum dose to tumor while achieving the minimum dose delivery to normal tissue; is the most important goal in external radiotherapy. Diode in vivo dosimetry is widely considered to be an important tool for quality improvement of patient care in external radiotherapy. Uncertainty in dose delivery should fall within 5% of the prescribed dose as recommended by International Commission of Radiological Units and Measurement (ICRU). In vivo dosimetry was implemented for treatments of 36 pelvis and 38 breast cancer patients which were treated by 60Co photon irradiation and 38 brain cancer patients which were treated by 6MV photon irradiation. The diode dosimeters that were used in this study were two different models of PTW products, T60010L model was used for 60Co photon beam and T60010M model was used for 6MV photon beams. The frequency histograms of the relative difference between the expected and measured doses at breast, pelvis and brain treatments, have mean values and standard deviations of -1.21% (7.01%), -0.44% (4.06%) and -1.32% (5.08%), respectively. Our study showed that the accurate prediction of the dose value at breast cancer treatment is harder than that at brain and pelvis cancer treatment and requires an estimation of the lack of scatter due to missing tissue. Quantitative verification of the prescribed daily dose is important in external radiotherapy to ensure precision in patient set-up accuracy in dose delivery.

The purpose of this study was to investigate the application of the Monte Carlo technique to calculate and analysis of dosimetric parameters for electron beams used in radiotherapy. This technique is based on statistical method and has a powerful role in different radiotherapy aspects. The simulated medical linear accelerator was the Varian Clinac 2100C. The electron beams 9, 12 and 20 MeV were simulated by MCNP4C Monte Carlo code. The beam geometry was 10 × 10 cm2 applicator, 100 cm SSD on the surface of homogenous water phantom. Central-axis percentage depth dose (PDD) curves and dose profile (off axis ratio) were obtained to compare with experimental measurements. The comparisons between calculated and experimental results show good agreement (within ±3%). The MCNP4C code is a powerful tool for acquiring electron dosimetry results as well as other applications in radiotherapy.

Gastric cancer is the fourth common malignancy and the second prevalent cause of cancer death in the world. Genetic and environmental factors play an important role in the development of this cancer. Nutritional and epidemiological studies have indicated that folate status modulates the risk of developing cancer and apoptosis has been reported to play a decisive role in precancerous changes. The aim of this cross-sectional study was to investigate whether there is any relationship between serum folic acid levels and apoptosis, as an early indicator of gastric cancer changes, in human gastric mucosa. This cross-sectional study was conducted on 62 patients out of 98 subjects with over 18 years old that referred to 2 hospitals in Tabriz, Iran to undergo an upper gastrointestinal endoscopy. We measured the levels of folic acid in serum and apoptosis was detected by TUNEL technique. We tested polynomial curve to find the best fit between them. The positive relation between serum folic acid and apoptosis found in the present study and our results indicate that the final and the best fit curve was: apoptosis =1.898+1.57×10-10× (Folic acid)8. Our study indicates the relation between level of folic acid in serum and apoptosis in human gastric mucosa was not linear and it is suggested more interventional and control study.

Androgen receptors (AR) play an important role in proliferation of cancerous prostatic cells and prevention of apoptotic signaling. Current drugs cannot inhibit the activity of these receptors very well. Establishment of appropriate animal models is essential for discovery of new drugs of target therapy in hormone dependent prostate cancer. Standard prostatic cancer cell line (PC-3) was injected heterotopically into 9 nude mice. After tumor formation they were excised and sent for histopathologic and AR expression studies by immunohistochemistry. Histological characteristics of prostate cancer were confirmed. Androgen receptors had been expressed in 65 ± 25% of the xenograft tumor cells. This xenograft model is suitable for pharmacological and molecular studies of androgen dependent prostate cancer.