Application of cell line based genomic predictors to predict response to targeted therapies in breast cancer

Cancer cell lines can be treated with a drug and the molecular comparison of responders and non-responders may yield potential predictors that could be tested in the clinic. It is a bioinformatics challenge to apply the cell line-derived multivariable response predictors to patients who respond to therapy. Using the gene expression data from 23 breast cancer cell lines, I developed three predictors of dasatinib sensitivity by selecting differentially expressed genes and applying different classification algorithms. The performance of these predictors on independent cell lines with known dasatinib response was tested. The predictor based on weighted voting method has the best overall performance. It correctly predicted dasatinib sensitivity in 11 out of 12 (92%) breast and 17 out of 23 (74%) lung cancer cell lines. These predictors were then applied to the gene expression data from 133 breast cancer patients in an attempt to predict how the patients might respond to dasatinib therapy. Two predictors identified 13 patients in common to be dasatinib sensitive. Sixty two percent of these cases are triple negative (ER-negative, HER2-negative and PR-negative) and 76% are double negative. The result is consistent with the findings from other studies, which identified a target population for dasatinib treatment to be triple negative or basal breast cancer subtype. In conclusion, we think that the cell line-derived dasatinib classifiers can be applied to the human patients. ^

Anticancer activity of OSW-1: Induction of apoptotic pathway in leukemia and autophagic death in pancreatic cancer through a calcium mediated mechanism

OSW-1 is a natural compound found in the bulbs of Orninithogalum saudersiae, a member of the lily family. This compound exhibits potent antitumor activity in vitro with the IC50 values in the low nanomolar concentration range and demonstrating its ability to kill drug resistant cancer cells. In an effort to discover the unknown mechanism of action of this novel compound as a potential anticancer agent, the main objective of this research project was to test the cytotoxicity of OSW-1 against various cancer lines, and to elucidate the biochemical and molecular mechanism(s) responsible for the anticancer activity of OSW-1. My initial investigation revealed that OSW-1 is effective in killing various cancer cells including pancreatic cancer cells and primary leukemia cells resistant to standard chemotherapeutic agents, and that non-malignant cells were less sensitive to this compound. Further studies revealed that in leukemia cells, OSW-1 causes a significant increase in cytosolic calcium and activates rapid calcium-dependent apoptosis by the intrinsic pathway. Additionally, OSW-1 treatment leads to the degradation of the ER chaperone GRP78/BiP implicated in the survival of cancer cells. Meanwhile, it shows a reduced sensitivity in respiration-deficient sub-clones of leukemia cells which had higher basal levels of Ca2+. Mechanistically, it was further demonstrated that cytosolic Ca2+ elevations were observed together with Na+ decreases in the cytosol, suggesting OSW-1 caused the calcium overload through inhibition of the Na+/Ca 2+exchanger (NCX). Although similar calcium disturbances were observed in pancreatic cancer cells, mechanistic studies revealed that autophagy served as an initial pro-survival mechanism subsequent to OSW-1 treatment but extended autophagy caused inevitable cell death. Furthermore, combination of OSW-1 with autophagy inhibitors significantly enhances the cytotoxicity against pancreatic cancer cells. Taken together, this study revealed the novel mechanism of OSW-1 which is through inhibition of the Na+/Ca2+ exchanger and provides a basis for using this compound in combination with other agents for the treatment of pancreatic cancer which is resistant to available anticancer drugs. ^

The critical role and regulation of transcription factor FoxM1 in gastric cancer development and progression

The mammalian Forkhead Box (Fox) transcription factor (FoxM1) is implicated in tumorgenesis. However, the role and regulation of FoxM1 in gastric cancer remain unknown.^ I examined FoxM1 expression in 86 cases of primary gastric cancer and 57 normal gastric tissue specimens. I found weak expression of FoxM1 protein in normal gastric mucosa, whereas I observed strong staining for FoxM1 in tumor-cell nuclei in various gastric tumors and lymph node metastases. The aberrant FoxM1 expression is associated with VEGF expression and increased angiogenesis in human gastric cancer. A Cox proportional hazards model revealed that FoxM1 expression was an independent prognostic factor in multivariate analysis. Furthermore, overexpression of FoxM1 by gene transfer significantly promoted the growth and metastasis of gastric cancer cells in orthotopic mouse models, whereas knockdown of FoxM1 expression by small interfering RNA did the opposite. Next, I observed that alteration of tumor growth and metastasis by elevated FoxM1 expression was directly correlated with alteration of VEGF expression and angiogenesis. In addition, promotion of gastric tumorigenesis by FoxM1 directly and significantly correlated with transactivation of vascular endothelial growth factor (VEGF) expression and elevation of angiogenesis. ^ To further investigate the underlying mechanisms that result in FoxM1 overexpression in gastric cancer, I investigated FoxM1 and Krüppel-like factor 4 (KLF4) expressions in primary gastric cancer and normal gastric tissue specimens. Concomitance of increased expression of FoxM1 protein and decreased expression of KLF4 protein was evident in human gastric cancer. Enforced KLF4 expression suppressed FoxM1 protein expression. Moreover, a region within the proximal FoxM1 promoter was identified to have KLF4-binding sites. Finally, I found an increased FoxM1 expression in gastric mucosa of villin-Cre -directed tissue specific Klf4-null mice.^ In summary, I offered both clinical and mechanistic evidence that dysregulated expression of FoxM1 play an important role in gastric cancer development and progression, while KLF4 mediates negative regulation of FoxM1 expression and its loss significantly contributes to FoxM1 dysregulation. ^

Mechanism of methylation gene reactivation in human cancer cells

Epigenetic silencing of tumor suppressor genes by DNA hypermethylation at promoter regions is a common event in carcinogenesis and tumor progression. Abrogation of methylation and reversal of epigenetic silencing is a very potent way in cancer treatment. However, the reactivation mechanisms are poorly understood. In this study, we first developed a cell line model system named YB5, derived from SW48 cancer cell line, which bears one copy of stably integrated EGFP gene on Chromosome 1p31.1 region. The GFP gene expression is transcriptionally silenced due to the hypermethylated promoter CMV. However, the GFP expression can be restored using demethylating agent 5-aza-2' deoxycytidine (DAC), and detected by FACS and fluorescent microscopy. Using this system, we observed the heterogeneous reactivation induced by DAC treatment. After flow sorting, GFP negative cells exhibited similar level of incomplete demethylation compared to GFP positive cells on repetitive LINE1 element, tumor suppressor genes such as P16, CDH13, and RASSF1a, and CMV promoter as well. However, the local chromatin of CMV-GFP locus altered to an open structure marked by high H3 lysine 9 acetylation and low H3 lysine 27 tri-methylation in GFP positive cells, while the GFP negative cells retained mostly the original repressive marks. Thus, we concluded that DAC induced DNA hypomethylation alone does not directly determine the level of re-expression, and the resetting of the local chromatin structure under hypomethylation environment is required for gene reactivation. Besides, a lentivirus vector-based shRNA screening was performed using the YB5 system. Although it is the rare chance that vector lands in the neighboring region of GFP, we found that the exogenous vector DNA inserted into the upstream region of GFP gene locus led to the promoter demethylation and reactivated the silenced GFP gene. Thus, epigenetic state can be affected by changing of the adjacent nucleic acid sequences. Further, this hypermethylation silenced system was utilized for epigenetic drug screening. We have found that DAC combined with carboplatin would enhance the GFP% yield and increase expression of other tumor suppressor genes than DAC alone, and this synergistic effect may be related to DNA repair process. In summary, these studies reveal that reversing of methylation silencing requires coordinated alterations of DNA methylation, chromatin structure, and local microenvironment. ^

Environmental sustainability and the human element: Decision making in National Cancer Institute-designated cancer centers and Practice Greenhealth subscribing institutions

Background. Various aspects of sustainability have taken root in the hospital environment; however, decisions to pursue sustainable practices within the framework of a master plan are not fully developed in National Cancer Institute (NCI) -designated cancer centers and subscribing institutions to the Practice Greenhealth (PGH) listserv.^ Methods. This cross sectional study was designed to identify the organizational characteristics each study group pursed to implement sustainability practices, describe the barriers they encountered and reasons behind their choices for undertaking certain sustainability practices. A web-based questionnaire was pilot tested, and then sent out to 64 NCI-designated cancer centers and 1638 subscribing institutions to the PGH listserv.^ Results. Complete responses were received from 39 NCI-designated cancer centers and 58 subscribing institutions to the PGH listserv. NCI-designated cancer centers reported greater progress in integrating sustainability criteria into design and construction projects than hospitals of institutions subscribing to the PHG listserv (p-value = <0.05). Statistically significant differences were also identified between these two study groups in undertaking work life options, conducting energy usage assessments, developing energy conservation and optimization plans, implementing solid waste and hazardous waste minimization programs, using energy efficient vehicles and reporting sustainability progress to external stakeholders. NCI-designated cancer centers were further along in implementing these programs (p-value = <0.05). In comparing the self-identified NCI-designated cancer centers to centers that indicated they were both and NCI and PGH, the later had made greater progress in using their collective buying power to pursue sustainable purchasing practices within the medical community (p-value = <0.05). In both study groups, recycling programs were well developed.^ Conclusions. Employee involvement was viewed as the most important reason for both study groups to pursue recycling initiatives and incorporated environmental criteria into purchasing decisions. A written sustainability commitment did not readily translate into a high percentage that had developed a sustainability master plan. Coordination of sustainability programs through a designated sustainability professional was not being undertaken by a large number of institutions within each study group. This may be due to the current economic downturn or management's attention to the emerging health care legislation being debated in congress. ^ Lifecycle assessments, an element of a carbon footprint, are seen as emerging areas of opportunity for health care institutions that can be used to evaluate the total lifecycle costs of products and services.^

The role of cardiovascular comorbidities in ovarian cancer survival

Objective. One facet of cancer care that often goes ignored is comorbidities, or diseases that exist in concert with cancer. Comorbid conditions may affect survival by influencing treatment decisions and prognosis. The purpose of this secondary data analysis was to identify whether a history of cardiovascular comorbidities among ovarian cancer patients influenced survival time at the University of Texas M. D. Anderson Cancer Center. The parent study, Project Peace, has a longitudinal design with an embedded randomized efficacy study which seeks to improve detection of depressive disorders in ovarian, peritoneal, and fallopian tube cancers. ^ Methods. Survival time was calculated for the 249 ovarian cancer patients abstracted by Project Peace staff. Cardiovascular comorbidities were documented as present, based upon information from medical records in addition to self reported comorbidities in a baseline study questionnaire. Kaplan-Meier survival curves were used to compare survival time among patients with a presence or absence of particular cardiovascular comorbidities. Cox Regression proportional models accounted for multivariable factors such as age, staging, family history of cardiovascular comorbidities, and treatment. ^ Results. Among our patient population, there was a statistically significant relationship between shorter survival time and a history of thrombosis, pericardial disease/tamponade, or COPD/pulmonary hypertension. Ovarian cancer patients with a history of thrombosis lived approximately half as long as patients without thrombosis (58.06 months vs. 121.55 months; p=.001). In addition, patients who suffered from pericardial disease/tamponade had poorer survival than those without a history of pericardial disease/tamponade (48 months vs. 80.07 months; p=.002). Ovarian cancer patients with a history of COPD or pulmonary hypertension had a median survival of 60.2 months, while the median survival for patients without these comorbidities was 80.2 months (p=.014). ^ Conclusion. Especially because of its relatively lower survival rate, greater emphasis needs to be placed on the potential influence of cardiovascular comorbid conditions in ovarian cancer.^

Racial/ethnic disparities in colorectal cancer screening and survival in a large nationwide population-based cohort

Background. Colorectal cancer (CRC) is the third most commonly diagnosed cancer (excluding skin cancer) in both men and women in the United States, with an estimated 148,810 new cases and 49,960 deaths in 2008 (1). Racial/ethnic disparities have been reported across the CRC care continuum. Studies have documented racial/ethnic disparities in CRC screening (2-9), but only a few studies have looked at these differences in CRC screening over time (9-11). No studies have compared these trends in a population with CRC and without cancer. Additionally, although there is evidence suggesting that hospital factors (e.g. teaching hospital status and NCI designation) are associated with CRC survival (12-16), no studies have sought to explain the racial/ethnic differences in survival by looking at differences in socio-demographics, tumor characteristics, screening, co-morbidities, treatment, as well as hospital characteristics. ^ Objectives and Methods. The overall goals of this dissertation were to describe the patterns and trends of racial/ethnic disparities in CRC screening (i.e. fecal occult blood test (FOBT), sigmoidoscopy (SIG) and colonoscopy (COL)) and to determine if racial/ethnic disparities in CRC survival are explained by differences in socio-demographic, tumor characteristics, screening, co-morbidities, treatment, and hospital factors. These goals were accomplished in a two-paper format.^ In Paper 1, "Racial/Ethnic Disparities and Trends in Colorectal Cancer Screening in Medicare Beneficiaries with Colorectal Cancer and without Cancer in SEER Areas, 1992-2002", the study population consisted of 50,186 Medicare beneficiaries diagnosed with CRC from 1992 to 2002 and 62,917 Medicare beneficiaries without cancer during the same time period. Both cohorts were aged 67 to 89 years and resided in 16 Surveillance, Epidemiology and End Results (SEER) regions of the United States. Screening procedures between 6 months and 3 years prior to the date of diagnosis for CRC patients and prior to the index date for persons without cancer were identified in Medicare claims. The crude and age-gender-adjusted percentages and odds ratios of receiving FOBT, SIG, or COL were calculated. Multivariable logistic regression was used to assess race/ethnicity on the odds of receiving CRC screening over time.^ Paper 2, "Racial/Ethnic Disparities in Colorectal Cancer Survival: To what extent are racial/ethnic disparities in survival explained by racial differences in socio-demographics, screening, co-morbidities, treatment, tumor or hospital characteristics", included a cohort of 50,186 Medicare beneficiaries diagnosed with CRC from 1992 to 2002 and residing in 16 SEER regions of the United States which were identified in the SEER-Medicare linked database. Survival was estimated using the Kaplan-Meier method. Cox proportional hazard modeling was used to estimate hazard ratios (HR) of mortality and 95% confidence intervals (95% CI).^ Results. The screening analysis demonstrated racial/ethnic disparities in screening over time among the cohort without cancer. From 1992 to 1995, Blacks and Hispanics were less likely than Whites to receive FOBT (OR=0.75, 95% CI: 0.65-0.87; OR=0.50, 95% CI: 0.34-0.72, respectively) but their odds of screening increased from 2000 to 2002 (OR=0.79, 95% CI: 0.72-0.85; OR=0.67, 95% CI: 0.54-0.75, respectively). Blacks and Hispanics were less likely than Whites to receive SIG from 1992 to 1995 (OR=0.75, 95% CI: 0.57-0.98; OR=0.29, 95% CI: 0.12-0.71, respectively), but their odds of screening increased from 2000 to 2002 (OR=0.79, 95% CI: 0.68-0.93; OR=0.50, 95% CI: 0.35-0.72, respectively).^ The survival analysis showed that Blacks had worse CRC-specific survival than Whites (HR: 1.33, 95% CI: 1.23-1.44), but this was reduced for stages I-III disease after full adjustment for socio-demographic, tumor characteristics, screening, co-morbidities, treatment and hospital characteristics (aHR=1.24, 95% CI: 1.14-1.35). Socioeconomic status, tumor characteristics, treatment and co-morbidities contributed to the reduction in hazard ratios between Blacks and Whites with stage I-III disease. Asians had better survival than Whites before (HR: 0.73, 95% CI: 0.64-0.82) and after (aHR: 0.80, 95% CI: 0.70-0.92) adjusting for all predictors for stage I-III disease. For stage IV, both Asians and Hispanics had better survival than Whites, and after full adjustment, survival improved (aHR=0.73, 95% CI: 0.63-0.84; aHR=0.74, 95% CI: 0.61-0.92, respectively).^ Conclusion. Screening disparities remain between Blacks and Whites, and Hispanics and Whites, but have decreased in recent years. Future studies should explore other factors that may contribute to screening disparities, such as physician recommendations and language/cultural barriers in this and younger populations.^ There were substantial racial/ethnic differences in CRC survival among older Whites, Blacks, Asians and Hispanics. Co-morbidities, SES, tumor characteristics, treatment and other predictor variables contributed to, but did not fully explain the CRC survival differences between Blacks and Whites. Future research should examine the role of quality of care, particularly the benefit of treatment and post-treatment surveillance, in racial disparities in survival.^

Gender differences in colorectal cancer screening and incidence in large nationwide, population-based cohorts

Background. A few studies have reported gender differences along the colorectal cancer (CRC) continuum but none has done so longitudinally to compare a cancer and a non-cancer populations.^ Objectives and Methods. To examine gender differences in colorectal cancer screening (CRCS); to examine trends in gender differences in CRC screening among two groups of patients (Medicare beneficiaries with and without cancer); to examine gender differences in CRC incidence; and to examine for any differences over time. In Paper 1, the study population consisted of men and women, ages 67–89 years, with CRC (73,666) or without any cancer (39,006), residing in 12 U.S. Surveillance Epidemiology and End-Results (SEER) regions. Crude and age-adjusted percentages and odds ratios of receiving fecal occult blood test (FOBT), sigmoidoscopy (SIG), or colonoscopy (COL) were calculated. Multivariable logistic regression was used to assess gender on the odds of receiving CRC screening over time.^ In Paper 2, age-adjusted incidence rates and proportions over time were reported across race, CRC subsite, CRC stage and SEER region for 373,956 patients, ages 40+ years, residing in 9 SEER regions and diagnosed with malignant CRC. ^ Results. Overall, women had higher CRC screening rates than men and screening rates in general were higher in the SEER sample of persons with CRC diagnosis. Significant temporal divergence in FOBT screening was observed between men and women in both cohorts. Although the largest temporal increases in screening rates were found for COL, especially among the cohort with CRC, little change in the gender gap was observed over time. Receipt of FOBT was significantly associated with female gender especially in the period of full Medicare coverage. Receipt of COL was also significantly associated with male gender, especially in the period of limited Medicare coverage.^ Overall, approximately equal numbers of men (187,973) and women (185,983) were diagnosed with malignant CRC. Men had significantly higher age-adjusted CRC incidence rates than women across all categories of age, race, subsite, stage and SEER region even though rates declined in all categories over time. Significant moderate increases in rate difference occurred among 40-59 year olds; significant reductions occurred among patients age 70+, within subsite rectum, unstaged and distant stage CRC, and eastern and western SEER regions. ^ Conclusions. Persistent gender differences in CRC incidence across time may have implications for gender-based interventions that take age into consideration. A shift toward proximal cancer was observed over time for both genders, but the high proportion of men who develop rectal cancer suggests that a greater proportion of men may need to be targeted with newer screening methods such as fecal DNA or COL. Although previous reports have documented higher CRC screening among men, higher incidence of CRC observed among men suggests that higher risk categories of men are probably not being reached. FOBT utilization rates among women have increased over time and the gender gap has widened between 1998 and 2005. COL utilization is associated with male gender but the differences over time are small.^

Hypogonadism in male cancer patients: A cross-sectional study

Introduction. Cancer is the second most common cause of death in the USA (2). Studies have shown a coexistence of cancer and hypogonadism (9,31,13). The majority of patients with cancer develop cachexia, which cannot be solely explained by anorexia seen in these patients. Testosterone is a male sex hormone which is known to increase muscle mass and strength, maintain cancellous bone mass, and increase cortical bone mass, in addition to improving libido, sexual desire, and fantasy (14). If a high prevalence of hypogonadism is detected in male cancer patients, and a significant difference exists in testosterone levels in cancer patients with cachexia versus those without cachexia, testosterone may be administered in future randomized trials to help alleviate cachexia. Study group and design The study group consisted of male cancer patients and non-cancer controls aged between 40 and 70 years. The primary study design was cross-sectional with a sample size of 135. The present data analysis is done on a subset convenience sample of 72 patients recruited between November 2006 and January 2010. ^ Methods. Patients aged 40-70 years with or without a diagnosis of cancer were recruited into the study. All patients with a BMI over 35, significant edema, non-melanomatous skin cancer, current alcohol or illicit drug abuse, concomitant usage of medications interfering with gonadal axis, and anabolic agents, patients on tube feeds or parenteral nutrition within 3 months prior to enrollment were excluded from the study. The study was approved by the Institutional Review Board of Baylor College of Medicine and is being conducted at the Michael E. DeBakey Veterans Affairs Medical Center at Houston. My thesis is a pilot data analysis that employs a smaller subset convenience sample of 72 patients determined by using the data available for the 72 patients (of the intended sample of 135 patients) recruited between November 2006 and January 2010. The primary aim of this analysis is to compare the proportion of patients with hypogonadism in the male cancer and non-cancer control groups, and to evaluate if a significant difference exists with respect to testosterone levels in male cancer patients with cachexia versus those without cachexia. The procedures of the study relevant to the current data analysis included blood collection to measure levels of testosterone and measurement of body weight to categorize cancer patients into cancer cachexia and cancer non-cachexia sub-groups. ^ Results. After logarithmic transformation of data of cancer and control groups, the unpaired t test with unequal variances was done. The proportion of patients with hypogonadism in the male cancer and non-cancer control groups was 47.5% and 22.7% with a Pearson chi2 statistic of 1.6036 and a p value of 0.205. Comparing the mean calculated Bioavailable testosterone in male cancer patients and non-cancer controls resulted in a t statistic of 21.83 and a p value less than 0.001. When the cancer group alone was taken, the mean free testosterone, calculated bioavailable testosterone and total testosterone levels in the cancer non-cachexia sub-group were 3.93, 5.09, 103.51 respectively and in the cancer cachexia sub-group were 3.58, 4.17, 84.08 respectively. The unpaired t test with equal variances showed that the two sub-groups had p values of 0.2015, 0.1842, and 0.4894 with respect to calculated bioavailable testosterone, free testosterone, and total testosterone respectively. ^ Conclusions. The small sample size of this exploratory study, resulting in a small power, does not allow us to draw definitive conclusions. For the given sub-sample, the proportion of patients with hypogonadism in the cancer group was not significantly different from that of patients with hypogonadism in the control group. Inferences on prevalence of hypogonadism in male cancer patients could not be made in this paper as the sub-sample is small and therefore not representative of the general population. However, there was a statistically significant difference in calculated Bioavailable testosterone levels in male cancer patients versus non-cancer controls. Analysis of cachectic and non-cachectic patients within the male cancer group showed no significant difference in testosterone levels (total, free, and calculated bioavailable testosterone) between both sub-groups. However, to re-iterate, this study is exploratory and the results may change once the complete dataset is obtained and analyzed. It however serves as a good template to guide further research and analysis.^

Genetic susceptibility, cigarette smoking, and wood dust exposure in lung cancer: Case control analyses

This case control study was conducted to assess the association between lung cancer risk, mutagen sensitivity (a marker of cancer susceptibility), and a putative lung carcinogen, wood dust exposure. There were 165 cases (98 African-Americans, 67 Mexican-Americans) with newly diagnosed, previously untreated lung cancer, and 239 controls, frequency-matched on age, sex, and ethnicity.^ Mutagen sensitivity ($\ge$1 break/cell) was associated with a statistically significant elevated risk for lung cancer (odds ratio (OR) = 4.1, 95% confidence limits (CL) = 2.3,7.2). Wood dust exposure was also a significant predictor of risk (OR = 2.8, 95% CL = 1.2,6.6) after controlling for smoking and mutagen sensitivity. When stratified by ethnicity, wood dust exposure was a significant risk factor for African-Americans (OR = 4.0, 95% CL = 1.4,11.5), but not for Mexican-Americans (OR = 1.5, 95% CL = 0.3,7.1). Stratified analysis suggested a greater than multiplicative interaction between wood dust exposure and both mutagen sensitivity and smoking.^ The cases had significantly more breaks on chromosomes 4 and 5 than the controls did with ORs of 4.9 (95% CL = 2.0, 11.7) and 3.9 (95% CL = 1.6, 9.3), respectively. Breaks at 4p14, 4q27, 4q31, 5q21-22, 5q31, and 5q33 were significantly more common in lung cancer patients than in controls. Lung cancer risk had a dose-response relationship with breaks on chromosomes 4 and 5. Cigarette smoking had a strong interaction with breaks on chromosomes 2, 4, and 5.^ In a molecular cytogenetic study, using chromosome painting and G-banding, we showed that: (1) the proportion of chromosome 5 abnormalities surviving as chromosome-type aberrations remained significantly higher in cells of lung cancer cases (14%) than in controls (5%) (P $<$ 0.001). However, no significant differences were detected in chromosome 4 abnormalities between cases and controls; (2) the proportion of chromosome 5q13-22 abnormalities was 5.3% in the cases and 0.7% in the controls (P $<$ 0.001). 5q13-22 regions represented 40% of all abnormalities on chromosome 5 in the cases and only 14% in the controls.^ This study suggests that mutagen sensitivity, wood dust exposure, and cigarette smoking were independent risk factors for lung cancer, and the susceptibility of particular chromosome loci to mutagenic damage may be a genetic marker for specific types of lung cancer. ^

Evaluating alternative therapies. Support/imagery and immune function in breast cancer: A pilot study

Cancer patients increasingly request alternative therapies such as imagery techniques and support groups. Although research suggests evidence of enhanced psychosocial functioning with supportive group therapy and enhanced immune function with imagery techniques, studies are anecdotal or limited to case studies or descriptive reports. The efficacy of these alternative therapies should be validated by randomized, controlled trials and the mechanisms of action mediating immune function and outcome examined.^ In a 12-month pilot study, we evaluate the feasibility of conducting a controlled study with clinical trial methodology to test the effects of imagery/relaxation and support on quality of life, emotional well-being, and immune function for women after breast cancer. Using a randomized pre-post test design with three intervention waves, we assigned women (n = 47) to either standard care (n = 15), standard care plus 6-weekly support sessions (n = 16) or imagery/relaxation sessions (n = 16).^ The primary aim of this pilot study is to determine the feasibility of conducting a clinical trial of alternative therapies in a clinical care setting. Secondary aims are to determine parameter estimates for the effects of the two treatment groups on quality of life, coping, social support, and immune function and describe methodology issues related to trials of alternative therapies.^ The research provides direction for future studies of alternative therapies by describing the recruitment, clinical trial experience, and related methodology issues. The study extends previous work by differentiating the effects of support group from mental imagery among outpatient groups who are homogeneous regarding cancer type and treatment stage. The study provides data for future longitudinal studies of disease progression by differentiating the effectiveness of interventions designed to enhance quality of life, coping, social support, and immune function and subsequently, alter the clinical course of disease. ^

The role and impact of transitional care utilization in colorectal cancer

BACKGROUND Although one out of every five gastrointestinal cancer patients needs transitional care (home-based skilled care or placement in skilled nursing or rehabilitation facilities) following treatment, few studies have examined outcomes in this population compared to patients who return home without assistance. This study has two primary goals: 1. To evaluate long-term cancer-specific outcomes in colorectal cancer patients utilizing transitional care compared to those that return home without assistance following therapy 2. To compare results using standard regression techniques and propensity scores. ^ METHODS Patients undergoing curative surgery for colorectal adenocarcinoma will be identified using data from a tertiary care Veterans Administration hospital. Survival and recurrence will then be determined from VA records and the Social Security Death Index. ^ The association between transitional care utilization and overall and disease-free survival will be evaluated using Cox proportional hazards regression to adjust for confounding factors. Predictors of transitional care utilization will be assessed using multiple logistic regression to generate a propensity score which will also be used to assess differences in survival based on transitional care use. ^ POTENTIAL SIGNIFICANCE If transitional care utilization is associated with worse survival and recurrence following therapy then it will be important to subsequently assess the mechanism in order to target interventions to improve outcomes. If there is no difference in cancer-specific outcomes, then this project can potentially highlight benefits of supportive therapy following colorectal cancer resection.^

Bisphosphonates for metastatic bone disease in lung cancer

Bisphosphonates have proven effectiveness in preventing skeletal-related events (SREs) in advanced breast cancer, prostate cancer and multiple myeloma. The purpose of this study was to assess efficacy of bisphosphonates in preventing SREs, in controlling pain, and in increasing life expectancy in lung cancer patients with bone metastases.^ We performed an electronic search in MEDLINE, EMBASE, Web of Science, and Cochrane library databases up to April 4, 2010. Hand searching and searching in clinicaltrials.gov were also performed. Two independent reviewers selected all clinical trials that included lung cancer patients with bone metastases treated with bisphosphonates. We excluded articles that involved cancers other than lung, patients without bone metastasis and treatment other than bisphosphonates. Outcome questions answered were efficacy measured as overall pain control, overall improvement in survival and reduction in skeletal-related events or SREs (fracture, cord compression, radiation or surgery to the bone, hypercalcemia of malignancy). The quality of each study was evaluated using the Cochrane Back Review group questionnaire to assess risk of bias (0-worst to 11-best). Data extraction and quality assessments were independently performed by two assessors. Meta-analyses were performed where more than one study with similar outcomes were found.^ We identified eight trials that met our inclusion criteria. Three studies evaluated zoledronic acid, three pamidronate, three clodronate and two ibandronate. Two were placebocontrol trials while two had multi-group comparisons (radiotherapy, radionucleotides, and chemotherapy) and two had different bisphosphonate as active controls. Quality scores ranged from 1-4 out of 11 suggesting high risk of bias. Studies failed to report adequate explanation of randomization procedures, concealment of randomization and blinding. Metaanalysis showed that patients treated with zoledronic acid alone had lower rates of developing SREs compared to placebo at 21 months (RR=0.80, 95% CI=0.66-0.97, p=0.02). Meta-analyses also showed increased pain control when a bisphosphonate was added to the existing treatment modality like chemotherapy or radiation (RR=1.17, 95% CI=1.03-1.34, p=0.02). However, pain control was not statistically significantly different among various bisphosphonates when other treatment modalities were not present. Despite improvement in SRE and pain control, bisphosphonates failed to show improvement in overall survival (Difference in means=109.1 days, 95% CI= -51.52 – 269.71, p=0.183).^ Adding biphosphonates to standard care improved pain control and reduced SREs. Biphosphonates did not improve overall survival. Further larger studies with higher quality are required to stengthen the evidence.^ Keywords/MeSH terms Bisphosphonates/diphosphonates: generic, chemical and trade names.^

Identification of micro-RNAs targeting genes of PI3K/AKT pathway in ovarian cancer

Ovarian cancer is the leading cause of cancer-related death for females due to lack of specific early detection method. It is of great interest to find molecular-based biomarkers which are sensitive and specific to ovarian cancer for early diagnosis, prognosis and therapeutics. miRNAs have been proposed to be potential biomarkers that could be used in cancer prevention and therapeutics. The current study analyzed the miRNA and mRNA expression data extracted from the Cancer Genome Atlas (TCGA) database. Using simple linear regression and multiple regression models, we found 71 miRNA-mRNA pairs which were negatively associated between 56 miRNAs and 24 genes of PI3K/AKT pathway. Among these miRNA and mRNA target pairs, 9 of them were in agreement with the predictions from the most commonly used target prediction programs including miRGen, miRDB, miRTarbase and miR2Disease. These shared miRNA-mRNA pairs were considered to be the most potential genes that were involved in ovarian cancer. Furthermore, 4 of the 9 target genes encode cell cycle or apoptosis related proteins including Cyclin D1, p21, FOXO1 and Bcl2, suggesting that their regulator miRNAs including miR-16, miR-96 and miR-21 most likely played important roles in promoting tumor growth through dysregulated cell cycle or apoptosis. miR-96 was also found to directly target IRS-1. In addition, the results showed that miR-17 and miR-9 may be involved in ovarian cancer through targeting JAK1. This study might provide evidence for using miRNA or miRNA profile as biomarker.^

EVIDENCE OF HUMAN ENDOGENOUS RETROVIRUS K INVOLVEMENT IN HUMAN CANCER

Many lines of clinical and experimental evidence indicate a viral role in carcinogenesis (1-6). Our access to patient plasma, serum, and tissue samples from invasive breast cancer (N=19), ductal carcinoma in situ (N=13), malignant ovarian cancer (N=12), and benign ovarian tumors (N=9), via IRB-approved and informed consent protocols through M.D. Anderson Cancer Center, as well as normal donor plasmas purchased from Gulf Coast Regional Blood Center (N=6), has allowed us to survey primary patient blood and tissue samples, healthy donor blood from the general population, as well as commercially available human cell lines for the presence of human endogenous retrovirus K (HERV-K) Env viral RNA (vRNA), protein, and viral particles. We hypothesize that HERV-K proteins are tumor-associated antigens and as such can be profiled and targeted in patients for diagnostic and therapeutic purposes. To test this hypothesis, we employed isopycnic ultracentrifugation, a microplate-based reverse transcriptase enzyme activity assay, reverse transcription – polymerase chain reaction (RT-PCR), cDNA sequencing, SDS-PAGE and western blotting, immunofluorescent staining, confocal microscopy, and transmission electron microscopy to evaluate v HERV-K activation in cancer. Data from large numbers of patients tested by reverse transcriptase activity assay were analyzed statistically by t-test to determine the potential use of this assay as a diagnostic tool for cancer. Significant reverse transcriptase enzyme activity was detected in 75% of ovarian cancer patients, 53.8% of ductal carcinoma in situ patient, and 42.1% of invasive breast cancer patient samples. Only 11.1% of benign ovarian patient and 16.7% of normal donor samples tested positive. HERV-K Env vRNA, or Env SU were detected in the majority of cancer types screened, as demonstrated by the results shown herein, and were largely absent in normal controls. These findings support our hypothesis that the presence of HERV-K in patient blood circulation is an indicator of cancer or pre-malignancy in vivo, that the presence of HERV-K Env on tumor cell surfaces is indicative of malignant phenotype, and that HERV-K Env is a tumor-associated antigen useful not only as a diagnostic screening tool to predict patient disease status, but also as an exploitable therapeutic target for various novel antibody-based immunotherapies.